# Patent

## Title
Export and modification of (poly)peptides in the lantibiotic way

## Abstract

The invention includes a method for harvesting a polypeptide produced by a host cell, wherein the polypeptide has not undergone intracellular posttranslational modification, such as dehydration of a serine or a threonine, and/or thioether bridge formation. The invention also includes a method for producing thioether-containing peptides and dehydroalanine/dehydrobutyrine-containing.peptides, wherein thioether rings may be formed extracellularly.

## Background
TECHNICAL FIELD
The invention relates generally to biotechnology and, more particularly, to the field of lantibiotics and to the field of posttranslational modifications of (poly)peptides.
BACKGROUND
Lantibiotics form a group of unique ribosomally synthesized and posttranslationally modified antibiotic peptides that are produced by, and primarily act on, Gram-positive bacteria (for review, See McAuliffe et al., FEMS Microbiol. Rev. 25: 285-308 (2001)). Because by definition lantibiotics contain intramolecular thioether bridges or rings formed by the thioether amino acids lanthionine (Lan) and 3-methyllanthionine (MeLan) and lantibiotics all are peptide antibiotics with moderate to strong bactericidal activity, lantibiotics take their name from these most eye-catching properties.
Thioether rings protect peptides against proteolytic degradation. For instance, the lantibiotic nisin remains active after trypsin treatment. Thioether rings are also essential for some lantibiotic activities. For instance, opening of ring A or C in nisin causes deletion of the membrane permeabilization capacity. Ring A of nisin is necessary for its capacity to autoinduce its own synthesis and for nisin's capacity to block the peptidoglycan synthesis by interacting with lipid II. It is essential to have thioether rings and not disulfide rings since replacement of thioether rings by disulfide bridges leads to loss of antimicrobial activity.
Lantibiotics do not spoil the environment and are not toxic to animals or man. Lantibiotics may also have applications as biopreservatives in the preparation of food and beverages, or as a bactericidal agent in cosmetics and veterinary and medical products. Because the growing number of multidrug resistant pathogenic micro-organisms has created the threat of another “pre-antibiotic era” for many bacterial diseases, it is expected that lantibiotics also may serve as new lead compounds to remedy this alarming problem. For these reasons, lantibiotics have experienced a marked increase in basic and applied research activities in the past decade, leading to an extraordinary increase in the knowledge of the lantibiotics structural and functional properties, the mechanisms of action and of the genes and protein components involved in the biosynthesis and secretion of the lantibiotics. For example, lantibiotics have become subject to “protein engineering” projects, with the aim of altering, via site-directed mutagenesis, the lantibiotics activity, stability and spectrum of susceptible target cells. In this description, the linear (type A) lantibiotics are considered since at present, very little specific information is available for the circular (type B) lantibiotics.
The lantibiotics subtilin and nisin belong to, and are representative of, the peptide antibiotics or lantibiotics of type A. Subtilin and nisin contain the rare amino acids dehydroalanine (Dha), dehydrobutyrine (Dhb), meso-lanthionine and 3-methyllanthionine, as well as the characterizing thioether bridges.
Nisin is the most prominent lantibiotic and is used as a food preservative due to its high potency against certain Gram-positive bacteria. It is produced by Lactococcus lactis strains belonging to serological group N. The potent bactericidal activities of nisin and many other lantibiotics are based on their capacity to permeabilize the cytoplasmic membrane of target bacteria. Breakdown of the membrane potential is initiated by the formation of pores through which molecules of low molecular weight are released. In addition, nisin inhibits cell wall synthesis by binding to lipid II, a precursor of peptidoglycan synthesis, modulates the activity of autolytic enzymes and inhibits the outgrowth of spores (See also, Breukink and de Kruijff, Biochem. Biophys. Acta 1462: 223-234, 1999).
In several countries, nisin is used to prevent the growth of clostridia in cheese and canned food. The nisin peptide structure was first described by Gross & Morell (J. Am. Chem. Soc 93: 4634-4635, 1971), and its structural gene was isolated in 1988 (Buchmann et al., J. Biol. Chem. 263: 16260-16266, 1988). Nisin has two natural variants, nisin A and nisin Z, which differ in a single amino acid residue at position 27 (histidine in nisin A is replaced by asparagine in nisin Z).
Subtilin is produced by Bacillus subtilis (ATCC 6633). Subtilin's chemical structure was first unravelled by Gross & Kiltz (Biochem. Biophys. Res. Commun. 50: 559-565, 1973) and its structural gene was isolated in 1988 (Banerjee & Hansen, J. Biol. Chem. 263: 9508-9514, 1988). Subtilin has strong similarities to nisin with an identical organization of the lanthionine ring structures (FIG. 1). Further, nisin and subtilin possess similar antibiotic activities.
Due to its easy genetic analysis B. subtilis became a suitable model organism for the identification and characterization of genes and proteins involved in lantibiotic biosynthesis. The pathway by which nisin is produced is very similar to that of subtilin and the proteins involved share significant homologies over the entire proteins (for review, see also, De Vos et al., Mol. Microbiol. 17: 427-437, 1995).
Another well known and studied lantibiotic, produced by Staphylococcus epidermis 5, is Pep 5, which contains three ring structures (one MeLan and two Lan), an N-terminal oxobutyryl residue and two Dhb residues (Kellner et al., Angew. Chemie Int. Ed. Engl. 28: 616-619, 1989).
The respective genes of subtilin and nisin have been identified adjacent to the structural genes, and are organized in operon-like structures (FIG. 2). The genes are thought to be responsible for posttranslation modification, transport of the modified prepeptide, proteolytic cleavage and immunity which prevents toxic effects on the producing bacterium. Further, biosynthesis of subtilin and nisin is strongly regulated by a two-component regulatory system which includes a histidine kinase and a response regulator protein.
According to a present model (FIG. 3), it is assumed that an extracellular growth phase-dependent signal may activate the membrane localized histidine kinase. The nature of the signal may be different for subtilin and nisin biosynthesis. In nisin biosynthesis, nisin has an inducing function, whereas it was shown for subtilin biosynthesis that its biosynthesis is sporulation dependent.
According to the model, after nisin's auto-phosphorylation, the SpaK and NisK histidine kinase transfer the phosphate residue to the response regulator which in turn activates the genes necessary for subtilin and nisin biosynthesis. Thereafter, the prepeptide is modified at a membrane localized modification complex (lantionine synthetase) including the intracellular SpaB/SpaC and the NisB/NisC proteins, respectively. According to the model, the proteins are also associated with the SpaT and the NisT transporter, respectively.
As in any lantibiotic, the presubtilin or prenisin molecule includes a leader segment and a mature segment, wherein the leader segment is thought to play several roles in the biosynthetic pathway. The leader segment is thought not to be just a translocation signal sequence, but also thought to provide recognition signals for the modification enzymes and to suppress antimicrobial activity until the mature peptide is released from the cell. As also postulated by Qiao and Saris, (Fems Microbiol. Let. 144: 89-93(1996)), the modified prepeptide is thought to be proteolytically cleaved after its transport through the cellular membrane or cleavage of the leader from the modified peptide occurs inside the cell before secretion. In the case of nisin, cleavage is performed by NisP, whereas in the case of subtilin, no specific protease has been found within the operon-like structure. However, B. subtilis is rich in extracellular proteases and possibly subtilisin, which also recognizes proline at position-2, could cleave the modified pre-subtilin.
The gene clusters flanking the structural genes for various linear (type A) lantibiotics have recently been characterized (for review, see, Siezen et al., Antonie van Leeuwenhoek 69: 171-184, 1996)). The best studied representatives are those of nisin (nis), subtilin (spa), epidermin (epi), Pep5 (pep), cytolysin (cyl), lactocin S (las) and lacticin 481 (lct). Comparison of the antibiotic gene clusters shows that the clusters contain conserved genes that probably encode similar functions.
The nis, spa, epi and pep clusters contain lanB and lanC genes that are presumed to code for two types of enzymes that have been implicated in the modification reactions characteristic of all antibiotics, i.e. dehydration and thio-ether ring formation. The cyl, las and lct gene clusters have no homologue of the lanB gene, but do contain a much larger lanM gene that is the lanC gene homologue. Most antibiotic gene clusters contain a lanP gene encoding a serine protease that is presumably involved in the proteolytic processing of the prelantibiotics. All clusters contain a lanT gene encoding an ATP-binding cassette (ABC)-like transporter spanning the plasma membrane of a cell and likely is involved in the export of (precursors of) the lantibiotics from the cell. The lanE, lanF and lanG genes in the nis, spa and epi clusters encode another transport system that is possibly involved in self-protection. In the nisin and subtilin gene clusters two tandem genes, lanR and lank, have been located that code for a two-component regulatory system.
Non-homologous genes are also found in some lantibiotic gene clusters. The nisL and spaI genes encode lipoproteins that are involved in immunity, the pepL gene encodes a membrane-located immunity protein and epiD encodes an enzyme involved in a posttranslational modification found only in the C-terminus of epidermin. Several genes of unknown function are also found in the las gene cluster. Commonly, a host organism or cell carrying one or more of the genes (e.g., lanT, lanI, lanA, lanP, lanB and lanC) in the cluster are identified with a shorthand notation such as lanTIAPBC. The above identified genes appear to be different from genes encoding the secretion apparatus for the non-lantibiotic lactococcins that includes two membrane proteins LcnC and LcnD, as discussed in Franke et al., J. Biol. Chem 274: 8484-8490, (1999).
A database has been assembled for all putative gene products of type A lantibiotic gene clusters. Database searches, multiple sequence alignment and secondary structure prediction have been used to identify conserved sequence segments in the LanB, LanC, LanE, LanF, LanG, LanK, LanP, LanM, LanR and LanT gene products that may be essential for structure and function (Siezen et al., ibid). The database allows for a rapid screening of newly determined sequences in lantibiotic gene clusters.
However, despite the above cited recent knowledge obtained in the field, attempts to engineer novel lantibiotic-like peptides comprising newly synthesized unnaturally occurring thioether bridges have been scarce, if not rather unsuccessful. In U.S. Pat. No. 5,861,275, nisin-subtilin chimeras have been produced in the Gram-positive Bacillus subtilus that do not comprise thioether bridges other than those naturally occurring in either nisin or subtillin. In a different application (U.S. Patent Application Publication 2002/0019518), Bacillus subtilus was used to produce a chimeric polypeptide comprising a lantibiotic peptide and a subtilin leader segment, a lantibody, that remains associated within the cell wall.
A novel thioether bridge in lantibiotic Pep5 has been engineered by Bierbaum et al., Appl. Env. Microbiol. 62: 385-392, (1996) by modifying the Gram-positive bacterium Staphylococcus epidermis 5 by depleting the host organism of the gene cluster pepTIAPBC and replacing pepTIAPBC with a gene cluster pepIAPBC, wherein pepA was or was not replaced with mutated structural genes encoding for Pep 5 peptide and wherein amino acids were substituted; genes coding for peptides with substitutions C27A (Cysteine to Alanine at position 27), C33A, A19C, Dhb16A, Dhb20A, K18Dha were generated. The A19C substitution resulted in novel thioether ring formation. The clone corresponding to the A19C substitution produced a small amount of a peptide that showed only little activity. It was thought that prolonged exposure of the peptide to intracellular protease of the producing transformed cell was causal to this disappointing result.
The K18Dha substitution in Pep5 resulted in a clone that produced incompletely dehydrated serine at position 18. Kuipers et al. (J. Biol. Chem. 267: 24340-24346, 1992) engineered a new Dhb residue into nisinZ by substituting M17Q/G18T in the lantibiotic, but also obtained incomplete dehydration of the resulting threonine and no additional ring formation. The incomplete dehydration is generally thought to be a result of questionable substrate specificity of the dehydrating enzyme LanB in the transformed cell.
In short, no large measure of success has yet been achieved in providing novel thioether bridges to lantibiotics in Gram-positive organisms, let alone that engineered thioether bridge formation has been provided to polypeptides of non-lantibiotic descent or by organisms other than Gram-positive bacteria.
Paul, Leena K et al. (FEMS Microbiol. Lett. 176: 45-50, 1999) recently studied the subtilin leader peptide as a translocation signal in the Gram-negative E. coli. By default, devoid of a specific lantibiotic transporter system and provided a fusion-protein comprising the subtilin leader peptide and part of the mature subtilin attached to E. coli alkaline phosphatase (AP) to study the possible translocation. Although the fusion protein was translocated to the periplasmic side of the cytoplasmic membrane, the fusion protein remained associated with that membrane. In earlier work (Izaguirre & Hansen, Appl. Environ. Microbiol 63: 3965-3971, 1997), the same fusion protein was expressed in the Gram-positive Bacillus subtilis, where the fusion protein was cleaved off from the membrane after successful translocation, but where no dehydration of serines or threonines of the AP polypeptide, let alone thioether bridge formation, was observed. Novak J et al., ASM general meeting 96: 217 (1999), recently provided an E. coli host cell with an ORF (ORF1) encoding an ABC transporter of 341 amino acids thought to be involved in the translocation of the lantibiotic mutacinII in Streptococcus mutans. However, an intact gene product of the ORF1 was not produced in E. coli, whereas a truncated protein of unknown identity or functionality was observed.
For the purpose of protein engineering of lantibiotics (for an extensive review see, Kuipers et al., Antonie van Leeuwenhoek 69: 161-170, 1996) or for the purpose of engineering newly designed (poly)peptides with lantibiotic-type posttranslational modifications, i.e., for example, for pharmaceutical use, much attention has recently (see, e.g., Entian & de Vos, Antoni van Leeuwenhoek supra; Siegers et al., J. Biol. Chem. 271: 1294-12301 (1996); Kiesau et al., J. Bacter. 179: 1475-1481 (1997)) been given to understanding the role of the LanB, LanC (or LanM) and LanT complex, the enzymes thought to be involved in dehydration, thioether ring formation and transportation of the lantibiotic out of the cell, respectively. However, the production of lantibiotic type heterologous proteins has not yet matured satisfactorily.
SUMMARY OF THE INVENTION
The invention provides a method allowing for the harvest of a desired (poly)peptide produced by a recombinant host cell. The method comprises the steps of a) selecting a recombinant host cell comprising a first nucleic acid comprising a first nucleic acid fragment encoding a leader peptide, and a second nucleic acid fragment encoding the desired (poly)peptide, whereby the first and second nucleic acid fragments are within the same open reading frame of the first nucleic acid and the leader peptide is at least functionally equivalent to a N-terminal leader peptide found with the prepeptide of a lantibiotic; b) selecting the host cell for the presence of a transporter protein commonly known as LanT or a functional equivalent thereof, and c) allowing the translation of the first nucleic acid and harvesting the desired (poly)peptide when the leader peptide (be it bound to or cleaved off from the desired (poly)peptide) is present in the culture medium of the cell.
In one embodiment, the leader peptide is freely available in the culture medium and is dissociated from host cell structures, such as the membrane or cell wall of the host cell. Considering the poor results obtained in the production of lantibiotic-type heterologous proteins, it was realized by the present inventors that until now, insufficient guidance was available on how to determine that a host cell system, thought to be suitably equipped with the machinery to provide for newly designed (poly)peptides with lantibiotic-type posttranslational modifications, was up to the task. As presented herein, it is realized that the presence of leader peptide in the culture medium of such a host cell system is a reliable measure of the capability of the system to produce such desired (poly)peptides.
It suffices to determine when, for a given host cell system, the presence or time point of appearance of such leader peptide in the culture system can be established to ascertain that actual production of the desired (poly)peptide (be it in modified or in as yet unmodified form) by the host cell system is expected and harvest can begin. The leader peptide can be detected each and every time in a host cell culture system set up to produce the desired (poly)peptide. However, for established cultures systems, harvest can be performed at time points which may be determined in pilot experiments with the culture systems.
The present invention shows that, until now, the field of the study of lantibiotic production has been looking on the wrong side of the cell membrane. The unmodified peptide coupled to its leader peptide can be transported out of the cell without prior modification, and LanB and LanC (or LanM) may act not inside, or outside of the cell (see also, FIG. 4). Now that this guidance for determining the suitability of a host cell culture system is available, as disclosed herein it is particularly useful for the production of desired heterologous (poly)peptides, which are of non-Gram-positive nature (i.e., Gram-negative prokaryotic), or essentially eukaryotic or viral descent.
Where it was earlier thought that LanB and LanC act in concert to modify the peptide only before it is translocated, it is disclosed herein that after transportation, the as yet unmodified peptide may undergo its specific posttranslational modification extracellularly leading to dehydration and thioether bridge formation, bringing the role of the transporter protein and the function of the leader peptide herein to central stage to modify a (poly)peptide in the lantibiotic way, it being a prerequisite to present the unmodified peptide to the modification machinery. It however also provides for improved production of unmodified or only partly modified heterologous proteins or peptides.
Thus, the invention also discloses the insight that dehydration of a serine or threonine of a (poly)peptide and subsequent thioether bridge formation can satisfactorily occur when a pre(poly)peptide has been transported out of the host cell wherein it was produced by translation, such as by a transporter protein such as an ABC transporter, or at least functionally corresponding to a transporter commonly identifiable as LanT. Dehydration (and optionally thioether bridge formation) is enzymatically catalyzed by an enzyme or enzymes that are at least functionally corresponding to LanB and/or LanC. The transporter transports the to-be-modified (poly)peptide through the membrane of the host cell where it is positioned in working proximity to extracellular located LanB for dehydration.
In a further embodiment, the invention discloses a method further comprising harvesting the desired (poly)peptide after detecting the presence of the leader peptide (be it bound to or cleaved off from the desired (poly)peptide) in the culture medium or supernatant of the cell (see also, FIG. 5). In the case of some small peptides, it is preferred to have not only the lantibiotic leader coding sequence in front of the desired peptide coding sequence, but the whole lantibiotic prepeptide coding sequence. The resulting fusion protein can be more easily detected and purified. Since, after ring formation, cleavage of the leader liberates the N-terminal site of the lantibiotic, very high sensitivity detection is possible by using the induction capacity of the lantibiotic. Furthermore, export is, in some cases, more efficient if the whole prepeptide precedes the desired peptide.
For detecting the presence, it is desirable that the medium contains a few nutrients, i.e., a so-called minimal medium. Also, it is desired that the presence is detected by harvesting the supernatant by aspirating and dispensing the supernatant into and out of a pipet tip (or other harvesting device) that contains a microvolume bed of affinity chromatography media fixed at the end of the tip that is without dead volume. This procedure is herein called “ziptipping” and allows, after subsequent elution, for relatively pure presentation of desired (poly)peptide for further analysis.
By using the combination of growth in minimal medium and ziptipping the supernatant of the culture, samples of sufficient purity can be obtained that are well suited for detection or analysis by high resolution MALDI-TOFMS. This allows a most significant measurement of leader peptide and, thus, prediction of desired (poly)peptide content, suitability of the host cell system used and suitable time-of-harvest of desired (poly)peptide. Detection of the leader peptide can, thus be used to ascertain the export of (poly)peptide coupled to this lantibiotic leader, such as in those cases where the leader peptidase acts extracellularly.
In a further embodiment, the invention discloses a method wherein the host cell producing the desired (poly)peptide is essentially devoid of leader peptidase (lanP) activity, thus allowing the production and extracellular harvest of desired (poly)peptide that is essentially still coupled to its leader peptide. In this way, potential intracellular toxic effects of desired (poly)peptide provided with thioether bridges are reduced. It suffices to design a leader peptide that cannot be cleaved by the leader peptidase of the host cell used. In both cases, the desired (poly)peptide can later be obtained free from the leader peptide, by, e.g., specific proteolytic cleavage using added lanP or another suitable protease capable of cleaving the leader peptide from the desired (poly)peptide.
It is also herein disclosed that in a desired (poly)peptide, a serine or serines that are N-terminally located from cysteines are dehydrated and coupled to more C-terminally located cysteines. As further exemplified herein, a (poly)peptide sequence with a serine and a cysteine `“S-C” contains (after thioether bridge formation) alanines in the positions of the serine and `cysteine: “A—A.” These alanines are coupled by, aside from the peptide backbone, a thioether bridge.
Generally, a method as provided herein allows a high detection level for measuring levels of (lantibiotic) (poly)peptides directly from the culture supernatant, considering that the ratio leader peptide versus desired (poly)peptide is essentially 1:1. Such guidance allows for efficient culture methods to produce the desired polypeptide and allows for determining appropriate or optimal time points at which the culture may be harvested.
In another embodiment, the invention discloses a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of peptide hormones, fragments of the peptide hormones or analogues from the peptide hormones originating from hypophysis and/or peptide hormones with similar actions including vasopressin, terlipressin, desmopressin, cispressin, oxytocin, adrenocorticotropic hormone and human growth hormone.
In yet another embodiment, the invention discloses a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of peptide hormones, fragments of the peptide hormones or analogues from the peptide hormones originating from hypothalamus, and/or peptide hormones with similar actions such as gonadoliberinII, luteinizing hormone, releasing hormone, leuprolide, and other synthetic analogues of LHRH including gonadorelin, goserelin, buserelin, leuproreline, nafarelin, triptorelin, cetrorelix, somatostatin, analogues of somatostatin, such as Octreotide, Somatostatine, corticotropin-inhibiting peptide, corticotropin-release factor, urocortin, urotensin II and growth hormone release factor. Specific LHRH-peptide analogues that are provided with a thioether ring structure is disclosed herein (see, Table 1).
Such distinct LHRH1 and LHRH2 and thioether bridge containing analogs are, for example, based on the peptide sequence of LHRH1 (SEQ ID NO: 1) or of LHRH2 (SEQ ID NO: 2). Such peptide sequences may be generated via recombinant means as described herein linked to a leader peptide, such as the nisin leader peptide (SEQ ID NO: 3). As disclosed herein, particular LHRH1- and LHRH2 thioether analogs were synthesized by exploiting the lantibiotic enzymes of the nisin producing Lactococcus lactis strain NZ9700. These enzymes involve a transporter molecule, NisT, a dehydrating enzyme, NisB that dehydrates serines and threonines and an enzyme, NisC that couples the dehydrated serines and threonines to cysteines giving the thioether ring.
Thioether bridged peptide-analogues were, for example, generated by cloning on a plasmid a nucleotide sequence that codes for a specific LHRH mutant behind the nisin leader (the particular LHRH analog coding sequence being followed by a stop codon).
In another embodiment, the invention discloses a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of peptide hormones, fragments of the peptide hormones or analogues from the peptide hormones originating from adrenocortex, adrenal medulla, kidney and heart and/or peptide hormones with similar actions such as adrenomedullin, angiotensin I, atrial natriuretic factor, bradykinin, brain natriuretic peptide, C-type natriuretic peptide and vasonatrin peptide.
In a further embodiment, the invention discloses a method and (poly)peptide wherein the desired (poly)peptide is selected from the group consisting of peptide hormones, fragments of the peptide hormones or analogues from the peptide hormones originating from other endocrine/exocrine organs such as the pancreas, thyroid, and parathyroid and/or peptide hormones with similar actions such as calcitonin, osteocalcin, glucagon, insulin, insulin-like growth factor-I or II, parathormone, and cholecystokinin.
In another embodiment, the invention disclosed a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of peptide hormones, fragments of the peptide hormones or (synthetic) analogues from the peptide hormones with antibiotic (-like) activity and/or peptide hormones with similar actions such as dermaseptin, defensin I, bombinin-like peptide, histatin-5, indolicidin, magainin-1 and ceratotoxin A.
In one embodiment, the invention discloses a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of biological active peptides, fragments of the biological active peptides and/or hormones or analogues from the biological active peptides and/or peptides with similar actions, such as exendin-3, secretin, human pancreatic polypeptide, peptide YY, gastric inhibitory polypeptide, big gastrin-I, pentagastrin, gastrin releasing peptide, motilin, neuropeptide Y, galanin, alpha-neurokinin, deltorphin, alpha-endorphin, beta-endorphin, leu-enkephalin, met-enkephalin, allatostatin I, anthopleurin-A, anti-inflammatory peptide 1, delta sleep inducing peptide, alpha-dendrotoxin, eledoisin, echistatin, small cardioactive peptide A or B, cerebellin, charybdotoxin, conopressin G, conotoxin EI, corazonin, experimental allergic encephalitogenic peptide, experimental autoimmune encephalomyelitis complementary peptide, tocinoic acid/pressinoic acid, brain-derived acidic fibroblast growth factor (1-11), brain derived acidic fibroblast growth factor (102-111), brain derived basic fibroblast growth factor (1-24), fibrinogen binding inhibitor peptide, fibroblast growth factor inhibitory peptide and transforming growth factor alpha.
In a further embodiment, the invention disclosed a method and a (poly)peptide wherein the desired (poly)peptide is selected from the group of biological active peptides, fragments of the biological active peptides and/or hormones or analogues from the biological active peptides and/or peptides with similar actions such as guanylin, helospectin I, hepatitis B surface antigen fragment, intercellular adhesion molecule, tachyplesin I, HIV (gp 120) antigenic peptide fragment, HIV (gp 41) antigenic peptide I fragment, HIV (gp41) antigenic peptide 5, HIV protease inhibitors, IGF II 69-84, interleukin-8 fragment, interleukin-2 fragment(60-70), leucokinin I, leukopyrokinin, mastoparan, melanin concentrating hormone, melittin, and ras oncogene related peptides.
Considering that lanthionine formation between, for example, dehydrobutyrine and cysteine is energetically possible at room temperature and can also occur spontaneously, the transported (poly)peptide can form thioether bridges spontaneously or where it is positioned in working proximity to extracellular located LanC for subsequent enzymatically induced thioether bridge formation. Alternatively, the transporter transports the to-be-modified polypeptide through the membrane of the host cell where it is positioned in working proximity to extracellularly located LanM for dehydration and subsequent thioether bridge formation.
The invention discloses a method from which several fields can benefit. In short, the invention discloses use of lantibiotic exporters (LanT) for export of peptides or proteins which may have been converted by lantibiotic enzyme(s), in particular, enabling extracellular formation of lanthionines and other rings. Amino acids are able to form short sequences (peptides) and longer sequences (proteins). Peptides and proteins (herein also referred to as “(poly)peptides”) are both important classes of biomolecules for nutrition, for pest control and for fighting disease. The lantibiotics importance is illustrated by the number and range of therapies based on the antibiotics recently created by the biochemical and pharmaceutical industries. There is also a large number of protein and peptide based pharmaceuticals and it should also be understood that the use of therapeutic pharmaceuticals is not limited to humans, but also extends to animal, plant and other biosystems. However, the manufacture of many present and potential protein or peptide pharmaceuticals has limitations since many protein or peptide pharmaceuticals are prepared in living cells (in vivo), but the cells must be ruptured or lysed (killed) and the contents extracted, separated, and purified in order to provide a given quantity of the peptide or protein. Since this is a complex process, the amount of any desired peptide or protein in any cell at any time is limited.
The present invention bypasses this problem by introducing a factor into the living cells which allows the cells to continuously transport proteins or peptides and export them through the cell wall, so that the product produced intercellularly may be collected extracellularly and the cells may remain vital and continue to produce materials. It is evident that this permits a substantially easier and higher rate of production of the desired products.
Since it is known that the LanT transporter or functional equivalent thereof acts on unmodified (poly)peptide to which the leader is still attached, one field relates to the expression and production of recombinant (poly)peptides, other than bacterial descent, and relates to expression and/or production of a (poly)peptide of eukaryotic (i.e., plant, animal or fungal origin) or viral descent. Such peptides are widely produced by recombinant means for use in the production of pharmaceuticals, such as active compounds including a (poly)peptide hormone, or cytokine, or antibody fragment, or biopesticide agent, or as antigens for a vaccine or immunogenic composition. It is now possible to use a lantibiotic-type transporter system to export peptides of eukaryotic, viral, and of bacterial (prokaryotic) descent.
In one embodiment, the invention disclosed a method that allows for extracellular harvest of a desired (poly)peptide (which may be out of the realm of bacterial lantibiotics or even be of eukaryotic or viral descent) produced by a recombinant host cell. The method comprises a) selecting a recombinant host cell comprising or provided with a first recombinant nucleic acid having a first nucleic acid fragment encoding a leader peptide and a second nucleic acid fragment encoding the desired (poly)peptide wherein the first and second nucleic acid fragments are within the same open reading frame of the first nucleic acid and the leader peptide is at least functionally equivalent to a N-terminal leader peptide found with the prepeptide of a lantibiotic; and b) selecting the host cell for the presence of a lantibiotic transporter protein commonly known as LanT, (such a host cell can be a Gram-positive or Gram-negative prokaryote or an eukaryote provided with such a transporter) and allowing for the translation of the first nucleic acid. In this embodiment, the cell is essentially devoid of leader peptidase activity, or comprises leader peptidase that cannot cleave the specific leader peptide used. Such a host cell may be obtained by deleting or functionally deleting, the lanP gene.
In another embodiment, the invention discloses a method allowing for extracellular harvest of a desired (poly)peptide which has not undergone intracellular posttranslational modification comprising dehydration of a serine or a threonine and/or thioether bridge formation. As described herein, it is demonstrated how to obtain nisin prepeptide (i.e., nisin leader and unmodified nisin) extracellularly. The nisin prepeptide was obtained using a host cell selected for the presence of two plasmids, one plasmid encoding the nisin prepeptide and one plasmid encoding NisT, wherein the host cell is further characterized by at least the functional absence of at least one of the other gene products derived from the Nis-gene cluster, such as NisB, NisC, or NisP.
The invention thus discloses a (poly)peptide harvestable after the (poly)peptide has been transported from the producing host cell, obviating the need to lyse or disrupt the host cells to harvest the (poly)peptide. Alternatively, the desired polypeptide may be harvested from within the cell. Cultures of cells provided with the transporter protein can be kept alive and in use, wherein the desired (poly)peptide can be harvested from the supernatant of spun-down host cells. The host cells need not be of Gram-positive descent per se, since Gram-negative prokaryotes or even eukaryotes can be provided with a properly placed transporter. Thus, the gamut of expression systems that can be used to express and produce a desired (poly)peptide is enhanced.
Furthermore, the invention discloses a method allowing for extracellular modification of a desired (poly)peptide produced by a recombinant host cell. The method comprises a) selecting a recombinant host cell comprising a first nucleic acid comprising a first nucleic acid fragment encoding a leader peptide and a second nucleic acid fragment encoding the desired (poly)peptide, wherein the first and second nucleic acid fragments are within the same open reading frame of the first nucleic acid and the leader peptide is at least functionally equivalent to a N-terminal leader peptide found with the prepeptide of a wild-type lantibiotic; b) selecting the host cell for the presence of a transporter protein such as LanT, or a functional equivalent thereof; c) selecting the host cell for the presence of an essentially extracellular protein (such as LanB, LanC or LanM) capable of providing posttranslational modification; and d) allowing for the translation of the first nucleic acid.
In one embodiment, the invention discloses a method allowing for extracellular modification of a desired (poly)peptide which has not undergone intracellular posttranslational modification comprising dehydration of a serine or a threonine and/or thioether bridge formation. In this embodiment, the essentially extracellular, albeit preferably cell-surface-bound, enzyme is capable of dehydrating a serine or a threonine, or is capable of providing for thioether bridge formation.
Further, the invention disclosed a method for lantibiotic-type modification of nonlantibiotic polypeptides, even when the (poly)peptide is of essentially eukaryotic or viral descent. This is useful for altering various characteristics of such products, for example related to stability or pharmacological profiles of useful polypeptides. It is of course useful to use a leader peptide or functional equivalents thereof.
Furthermore, the invention discloses a method allowing for extracellular modification of a desired (poly)peptide produced by a recombinant host cell, wherein the modification comprises thioether bridge formation. The location of serines, threonines or cysteines in the desired (poly)peptide may be selected such that thioether ring formation by the enzyme system selected follows naturally. For example, serine and threonine dehydration, may be followed by thioether ring formation by coupling to cysteines as follows. In the case of lantibiotic enzymes belonging to the type B lantibiotics, ring formation may occur from dehydrated serines/threonines to more C-terminally or to more N-terminally located cysteines. In the case of lantibiotic enzymes belonging to type A lantibiotics, ring formation may occur from dehydrated serines/threonines to more C-terminally located cysteines. Conversion by enzymes belonging to type A lantibiotics occurs in time from N to C-terminal direction from dehydrated serines/threonines to the nearest more C-terminally located available cysteine. In the case of enzymes belonging to type A lantibiotics, a preferential distance of one to four amino acids to available cysteines is disclosed to form lanthionines. It is possible that 2 to 3 amino acids are between a dehydrated serine/threonine on the one hand and a cysteine on the other hand, wherein the optimal distance is two amino acids.
As disclosed in Table 1, peptides with the above preferred distances for optimal thioetherbridge formation may be selected. At distances between four and thirteen amino acids, lanthionine formation can occur but is less efficient. At these distances, dehydration of serines and threonines without subsequent lanthionine formation and next to no dehydration of serine/threonine occurs. It is possible to have flanking regions of serines and threonines that allow activity of the dehydrating enzyme. To achieve this, at least the six to eight amino acids (three to four on each side) surrounding dehydrated serines/threonines are substantially hydrophobic. At each of these positions in 40-80% of the cases, the amino acid is hydrophobic, in 20-40% hydrophilic, of which in 5-15% positively charged. For best efficiency, negatively charged amino acids rarely occur. The composition of the flanking regions on the desired (poly)peptide may differ from the one of serine and threonine in lantibiotic-type leader peptides. In leader peptides, serines and threonines occur, but are not dehydrated, whereas cysteines do not occur. The six to eight positions most proximate to leader serines/threonines contain less hydrophobic amino acids and more negatively charged amino acid than in positions around propeptide serine/threonine per position around 20-40% of the cases the amino acid is hydrophobic and around 20% of the cases a negatively charged amino acid is disclosed.
With respect to the peptidase cleavage site, at least two types of leader peptides exist from which guidance can be obtained to design better cleavable peptides or proteins. One type used the subtilisin-like serine protease LanP for cleavage, which occurs after Pro-Gln, Pro-Arg, Ala-Asp, or Ala-Glu. In the case of nisin, a positively charged residue at position −1 and a hydrophobic residue at position −4 appears necessary for interaction with NisP. This subtilisin-like serine protease LanP acts on the prepeptides of Pep5, Epilancin K7, Nisin A, Nisin-Z, Epidermin, and Gallidermin.
In the other type, the leader peptides are cleaved after Gly-Gly, Gly-Ala or Gly-Ser sequences. The latter holds for many other non lantibiotic bacteriocin leader peptides. The subtilisin like proteases are not known to cleave these sequences and a different type of protease is cleaving these leader peptides. It has been shown that in some bacteriocins, both lantibiotic and nonlantibiotic this second protease is a domain of the transport system LanT. This type of leader peptidase acts on prepeptides of Lacticin-481, Variacin, Mutacin-II, Streptococcin-A-FF22, Salivaricin-A, and Sublancin.
In addition, a two component lantibiotic, Cytolysin-LL/Cytolysin LS, exists of which each component is cleaved twice. One cleavage is by the “double glycine type” and the other cleavage is by the subtilisin-like peptidase.
The invention further disclosed a method for the modification of a desired polypeptide wherein the host cell is a Gram-negative prokaryote or a eukaryote. The invention also discloses a (poly)peptide modified, using a method of the invention.
The invention further discloses a host cell, such as a Gram-negative prokaryote or an eukaryote, provided with a recombinant nucleic acid comprising a first nucleic acid fragment encoding a leader peptide and a second nucleic acid fragment encoding a desired (poly)peptide, wherein the first and second nucleic acid fragments are within the same open reading frame of the first nucleic acid and the leader peptide is at least functionally equivalent to an N-terminal leader peptide found with the prepeptide of a lantibiotic. In one embodiment, a host cell is disclosed wherein the desired (poly)peptide is of essentially eukaryotic or viral descent, such as those disclosed in Table 1 and/or wherein the leader peptide is one of those disclosed in Table 2.
The invention also discloses a host cell provided with or selected for the presence of at least a LanT protein, or a functional equivalent thereof, wherein the host cell is further characterized by at least the functional absence of at least one of the other gene products derived from the Lan-gene cluster, such as LanB, LanC, (or a functional part from LanM) or LanP. The host cell comprises a Gram-negative prokaryote or a eukaryote.
The host cell disclosed herein has a specific use in a method of producing a (poly)peptide for harvest or modification, as disclosed herein above. For the purpose of harvest, LanT is present, but LanB and/or LanC (or LanM) are absent, or at least functionally absent, in that they are hampered in binding to or interfering with the polypeptide to be harvested. For the purpose of modification, LanT and an essentially extracellular protein allowing extracellular modification is present. The extracellular protein may be LanB, LanC, LanM, or an N-terminal) LanM fragment having LanB function, on a C-terminal LanM fragment having LanC function. A further extended or even complete lantibiotic gene-product cluster is preferably at least not functionally present.
The invention further discloses a recombinant nucleic acid comprising a first nucleic acid fragment encoding a leader peptide and a second nucleic acid fragment encoding a desired (poly)peptide, wherein the first and second nucleic acid fragments are within the same open reading frame of the first nucleic acid and the leader peptide is at least functionally equivalent to a N-terminal leader peptide found with the prepeptide of a lantibiotic, and wherein the desired (poly)peptide is of essentially eukaryotic or viral descent.
The invention also disclosed a proteinaceous substance comprising a polypeptide encoded by a nucleic acid. Such a proteinaceous substance can be harvested, or modified as previously disclosed herein. Use of a host cell, nucleic acid or proteinaceous substance of the present invention for the production of a desired (poly)peptide, and its use in producing a pharmaceutical composition are herein also disclosed. In particular, the invention discloses a (poly)peptide of Gram-negative prokaryotic, viral or eukaryotic descent (such as those of Table 1) wherein a serine or threonine has been dehydrated or which has been provided with a thioether bridge. The advantage of such a polypeptide lays in the creation of variants of known peptides or protein based drugs, where the dose or frequency of administration can be reduced to lower treatment cost, treatment time, and patient inconvenience.
The creation of variants of new protein or peptide based drugs, where the drug may not have been effective or admitted for use in an unstabilized form, and the creation of new therapeutic entities per se is further explained in the following detailed description.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1: Peptide structure of mature nisin and subtilin.
FIG. 2: Genomic organization of genes involved in subtilin and nisin biosynthesis.
FIG. 3: Model for nisin biosynthesis wherein modification occurs intracellularly.
FIG. 4: Model for nisin biosynthesis wherein modification occurs extracellularly. Nisin prepeptide is exported by NisT (“T”), dehydrated by extracellular NisB (B) and subjected to thioether ring closure by extracellular NisC (C). Extracellular leader peptidase, NisP (P) cleaves of the leader peptide. Nisin interacts with a membrane bound histidine kinase NisK (K) which phosphorylates a response regulator NisR (R), which in its turn switches on transcription of the nis-genes (+, +). The producer cells are protected against nisin by the concerted action of the lipopeptide NisI and the transport system NisEFG.
FIG. 5: Detection of lantibiotic leader peptide from the culture medium by MALDI-TOFMS. By using the combination of growth in minimal medium and ziptipping the supernatant of the culture, samples of sufficient purity were obtained for high resolution MALDI-TOFMS. This allowed most significant measurement of nisin leader peptide. The detection of lantibiotic leader peptide can be used to ascertain the export of (poly)peptide coupled to this lantibiotic leader, i.e., in those cases where the leader peptidase acts extracellularly. Generally the method allows a high detection level for measuring (lantibiotic) (poly)peptides directly from the culture supernatant.
FIGS. 6A and 6B: The NisT transporter can transport unmodified nisin prepeptide. Lactococcus lactis strain NZ9000 with plasmids coding for the transporter, NisT and for the nisA product, nisin prepeptide, was grown in M17 medium and transcription of nisT and nisA was induced in minimal medium. Samples were prepared by ziptipping the culture supernatant and analyzed by MALDI TOFMS. A mass peak (theoretical mass of 5,831.8 Da) corresponding to unmodified nisin prepeptide was measured. A second peak has a mass consistent with the nisin prepeptide with methionine of position 1 still attached to it (theoretical mass of 5,963 Da). This demonstrates that NisT is sufficient for the transport of unmodified prepeptide to the exterior of the cell. For detailed information see example 1.
FIG. 7A: MALDI TOFMS analysis of ziptipped minimal medium supernatant from NZ9700+pNG-nisinleader-(L7C)LHRH. The peak at 1,169.9 Da corresponds to the thioether ring containing LHRH and the peak of 2,351.8 to the nisin leader. Secretion of the thioether ring stabilized (L7C)LHRH by Lactococcus lactis NZ9700. L7C-LHRH (a luteinizing hormone release hormone mutant) was fused to the nisin leader peptide by cloning the L7C-LHRH coding sequence behind the nisin leader in an expression vector. The lactococcal strain NZ9700 (a nisin producing L. lactis strain) is used for expression of the leader peptide-(L7C)LHRH fusion. The enzyme NisB dehydrates serine at position 4 and this dehydrated residue is coupled to the cysteine of position 7 by enzyme NisC to form a thioether bridge. The leader peptidase NisP cleaves of the leader peptide.
FIG. 7B: Structure of the nisin leader and thioether LHRH.
FIG. 8: Suitable LHRH analogues.



DETAILED DESCRIPTION
Lantibiotic enzymes are special. There is no strong homology with other enzymes. DNA and amino acid sequences of many lantibiotic enzymes are known, but no structures have been determined. The genes involved in the biosynthesis, processing and export of lantibiotics are present in a lanA B C/M (D) P R K T F E G I cluster. No uniform order or orientation of the genes in the different clusters exists indicating that rearrangements have occurred in the evolution.
Lanthionines are the most typical posttranslationally formed residues in antibiotics. They are formed via two steps. First, propeptide serines and threonines are dehydrated giving rise to dehydro-alanines and dehydrobutyrines, respectively. LanB has been proposed to play a role in dehydration, since it has a weak homology to IIvA, a threonine dehydratase from E. coli. It has also been shown that overexpression of NisB increases the occurrence of dehydration of serine 33 in nisin A, from 10% in the normal situation up to 50% in the case of overexpressed NisB. The LanB protein includes about 1,000 residues. LanB is a membrane associated protein.
LanC is thought to be responsible for the subsequent addition of cysteine SH groups to the dehydro amino acids, which results in the thioether rings. In the case of PepC, experimental data support this idea. Known LanC proteins include about 400 residues. In type A lantibiotics, the N-terminal part of lanthionine and methyllanthionine residues are formed by the dehydroalanine or dehydrobutyrine residues, whereas the C-terminal half is formed by the cysteine residues. Lanthionine formation between dehydrobutyrine and cysteine is energetically possible at room temperature and can also occur spontaneously.
Lantibiotic maturation and secretion is thought to occur at membrane-associated multimeric lanthionine synthetase complex including proteins LanB, LanC and the ABC transporter molecules LanT. At least two molecules of LanC and two molecules of LanT are part of the modification and transport complex. Some lantibiotics do not have the lanB gene, but have a larger lanM gene, whose product has some C-terminal homology with the lanC gene product. Since no lanB homologue is present in LanM-producing clusters, the N-terminal part of the LanM protein may perform the dehydration reaction typically performed by LanB.
Lantibiotics may be chemically synthesized, but the process is extremely costly and time consuming. Several mutant lantibiotics containing amino acid substitutions have been obtained by genetic engineering. However, despite many studies, only in the lantibiotic Pep5 one lanthionine ring has a new position been obtained.
The lantibiotic export systems, LanT, (whose sequences are known) are thought to be dedicated for the transport of the fully modified lantibiotic. The two enzymes involved in the lanthionine formation in nisin (NisB and NisC) have been reported to be located intracellularly in a NisBCT membrane associated complex (Siegers et al., 1996). Such intracellular localization suggests that the prepeptides are dehydrated by LanB where rings are formed by LanC and followed by export by LanT. Further, if the thioether ring-forming enzymes, NisB (which is responsible for dehydration, the first step in ring formation) or NisC (responsible for ring formation between dehydrated residues and cysteines) are inactivated by an in frame deletion of 61aa or by plasmid insertion respectively, no peptide is exported. The latter suggests that absence of (methyl)lanthionines prevent export.
However, it has been measured that prepeptide, such as nisin prepeptide, can be transported through the nisin transporter. This result was obtained using a strain with two plasmids, one plasmid coding for the nisin prepeptide and one plasmid coding for the nisin transporter. No prepeptide production was observed in a control experiment in which a strain with only the plasmid coding for the prepeptide was used. Some lantibiotics contain dehydrated serines/threonines that do not participate in thioether ring formation. From the latter, in combination with the observation that an unmodified peptide is exported, it may also be theorized that translocation of prepeptide without thioether rings, but with dehydrated residues, is possible. It is known that the second step in lanthionine ring formation is less difficult to achieve since it can also occur spontaneously at room temperature. After production of prepeptides with dehydrated residues, lanthionine rings can be formed extracellularly.
The finding disclosed herein provides the possibility to make new lantibiotics and, thus, to stabilize peptides/proteins by thioether rings, D-alanines or other residues formed by lantibiotic enzymes. Before (methyl)lanthionine formation, the distance of dehydrated residues to cysteines is typically 2-5 residues, but larger distances are possible. (Methyl)lanthionines can be formed from dehydrated residues to more N-terminally located or to more C-terminally located cysteines. In addition, the lantibiotic transport system can be used for the export of other proteins by inserting the sequence coding for the leader peptide in front of the protein DNA sequence.
Several uses are foreseen. For instance, peptide/protein drugs that are rapidly degraded in the blood plasma can be protected from proteolysis by thioether rings. Also, new lantibiotics can be used as antibiotics, especially against Gram-positive bacteria. This is useful since there is a growing and spreading resistance against classical antibiotics. New lantibiotics can be also be used as food additives to prevent bacterial growth and increase the shelf life of food products. Mastering the enzymatic synthesis of thioether rings further furnishes the possibility of synthesizing a broad variety of new antimicrobial peptides, which gives many possibilities to circumvent resistance. Lantibiotics have a variety of antimicrobial activities including membrane permeabilization, inhibition of cell wall synthesis, modulation of enzyme activities, and inhibition of outgrowth of spores. New lantibiotic-type peptides or proteins have modulated activity or a different spectrum of activity. A selection of such peptides or proteins is described herein in the examples given below.
EXAMPLE 1
The NisT Transporter can Transport Unmodified Nisin Prepeptide.
This example involves a L. lactis strain that lacks the entire chromosomal nisin gene cluster, but simultaneously produces plasmid encoded NisT and the NisA prepeptide. Unmodified NisA can be found in the culture supernatant, which demonstrates that NisT is sufficient for the transport of unmodified prepeptides to the exterior of the cell.
Materials and Methods. Use for the nisin inducible expression of nisT in L. lactis, a pNZ8048 (Kuipers et al. 1997, Tibtech. 15: 135-140) derived plasmid. The nisT gene was amplified using primers NisT.fw (5′-CGG TCT CCC ATG GAT GAA GTG AAA GAA TTC ACA TCA AAA C (SEQ ID NO: 4)) and NisT.rev (5′-CGG TCT CTC TAG ATT ATT CAT CAT TAT CCT CAT ATT GCT CTG (SEQ ID NO: 5)) with chromosomal DNA of NZ9700 (a nisin producing L. lactis strain; Kuipers et al. 1997, Tibtech. 15: 135-140) as a template. PCR conditions used include: 5 min 94° C., 30 times (30s 94° C., 30s 50° C., 3 min 72° C.), 10 min 72° C. The PCR products are purified with the Roche PCR-isolation kit. The expression vector is digested with NcoI/XbaI and the PCR fragments are digested with Eco31I (nucleotides 2-6 in the primers; the sticky ends it generated are at nucleotides 9-12 were compatible with NcoI and XhaI) and the fragments are subsequently ligated using T4 ligase (Roche). The resulting plasmid was designated pNG-nisT and contains a chloramphenicol (Cm) resistance gene as a selection marker.
Use for the nisin inducible production of the NisA prepeptide in L. lactis, a variant of pNZ8048 that contains an erythromycin (Em) resistance selection marker instead of a Cm marker. The nisA gene is amplified using primers NisA.fw (5′-CGG TCT CTC ATG AGT ACA AAA GAT TTT AAC TTG GAT TTG G (SEQ ID NO: 6)) and NisA.rev (5′-TAT ATG GAT CCT TTG CTT ACG TGA ATA CTA CAA TGA CAA G (SEQ ID NO: 7)) and chromosomal DNA of strain NZ9700 as a template under the same conditions as described above. The PCR product is purified with the Roche PCR-isolation kit. The expression vector was digested with NcoI/BamHI and the PCR fragment is digested with Eco31I and BamHI (nucleotides 2-6 in the primers; the sticky ends it generated are at nucleotides 9-12 were compatible with NcoI and BamHI) and the fragments are subsequently ligated using T4 ligase (Roche). The resulting plasmid is designated pNG-nisA.
L. lactis strains NZ9000 or PA1001 (a NZ9000 derivative lacking AcmA activity to abolish cell lysis (Buist et al. 1995, J. Bacteriol. 177: 1554-1563) and lacking HtrA to diminish extracellular proteolytic activity (Poquet et al. 2000, Mol. Microbiol. 35: 1042-1051)) with both pNG-nisT (Cm) and pNG-nisA (Em) are grown in M17-based medium (Terzaghi and Sandine, Appl. Microbiol., 29: 807-813 (1975)) to an OD600 of 0.4. The cells are collected by centrifugation and resuspended in the same volume of Minimal Medium (Jensen and Hammer, 1993, Appl. Environ. Microbiol. 59: 4363-4366) and expression of NisT and NisA prepeptide was induced by addition of nisin as described (Kuipers et al. 1997, Tibtech. 15: 135-140). After overnight induction and subsequent centrifugation, the culture supernatants are pipeted up and down in C18 ZIPTIPSTM (Millipore) two times using 10 μl 50% acetonitril, followed by two times using 10 μl demineralized water, followed by eight times using 10 μl supernatant. The culture supernatants are then washed two times with 10 μl demineralized water, followed by elution two times with 10 μl 50% acetonitril containing 0.1% TFA. The final eluent is vacuum dried and stored at −20° C. until analysis by mass spectrometry. Prior to analysis, the dry material is resuspended in 2.5 μl of 50% acetonitril containing 0.1% TFA and 1 μl is applied to the target. After drying, 1 μl of matrix (10 mg/ml alpha-cyano-4-hydroxycinnamic acid completely dissolved (by mildly heating and vortexing) in 50% acetonitril containing 0.1% TFA) was applied to the target. The following MALDI-TOFMS (linear mode) laser settings were used: 100% coarse energy, 50% fine, source 20 KV, extra 19800, force 15000, suppression 500, pulse time 40, pulse voltage 2200, sampling rate 500 MHz, sensitivity 50 mV, shots 15.
Results: Analyze culture-supernatants of the following induced cultures and analyze by MALDI-TOFMS:

    
    
        NZ9000 (or PA1001);
        NZ9000 (pNG-nisA) (or PA1001(pNG-nisA)); and
        NZ9000 (pNG-nisA+pNG-nisT) or (PA1001(pNG-nisA+pNG-nisT)).
    
    


No peaks were observed in samples derived from cultures A and B. Two main peaks were observed in sample C. The first peak is close to, or identical, to 5832.8 Da which corresponds to the unmodified nisin prepeptide: (5831.8 plus 1 proton). The second peak was about 130 Da higher mass than the first peak, which might correspond to the nisin prepeptide with two zinc atoms (Bierbaum, G. 1999, Ed. J. W. Kelly, Amino acids, Peptides, Porphyrins, Alkaloids 4, 275-301. Elsevier, Comprehensive Natural Products Chemistry, Eds. D. Barton, K. Nakanishi & O. Meth-Cohn) or the nisin prepeptide with the methionine in position 1 still present. This first peak is consistent with unmodified nisin prepeptide being transported by the nisin transporter NisT. This result demonstrates that NisT is sufficient for the transport of the nisin prepeptide and that modification is not required prior to transport.
EXAMPLE 2
Secretion of the Hydrophobin SC3 of the Fungus Schizophyllum commune by Lactococcus lactis through the use of the nisin A leader peptide and the nisin transport system NisT.
To study the role of the nisin A leader peptide in secretion through NisT in L. lactis, a strain that lacks the entire chromosomal nisin gene cluster was constructed, but produces simultaneously encoded plasmid NisT and the fungal hydrophobin SC3 fused to the NisA leader peptide. The fusion product is present in the culture supernatant, which demonstrates that the NisA leader peptide can be used to drive the transport of polypeptides other than nisin derivatives through the NisT transporter.
Materials and methods. A NisA leader peptide-SC3 fusion was constructed in a pNZ8048 expression vector that contains a c-myc epitope, which can be used for the detection of expressed polypeptides. For that purpose, a BglII-NcoI fragment upstream the c-myc epitope in the vector was replaced by a BglII-NcoI fragment of the NZ9700 chromosomal DNA that contains the nisA promoter and the nisA leader peptide (ending at amino acid sequence: . . . GASPR) (SEQ ID NO: 8)). A chromosomal fragment was obtained by PCR amplification using primers: NisA.fw3 (5′-CGG TCT CAG ATC AAT AGA AAC ATT AAC AAA TCT AAA ACA G (SEQ ID NO: 9)) and NisA.rev3 (5′-CGG TCT CA CAT GGA GCG TGG TGA TGC ACC TGA ATC (SEQ ID NO: 10)). The same PCR conditions used in Example 1 were applied. The PCR product was purified with the Roche PCR-isolation kit and digested with Eco31I (sites at nucleotides 2-6 in the primer sequences). This process results in a PCR fragment with BglII-NcoI sticky ends (at nucleotides 9-12 in the primer sequences). The BglII-NcoI digested vector and the cut PCR fragment were ligated and the newly obtained vector with the NisA leader peptide sequence upstream the c-myc epitope sequence was designated pNG-nisL. The SC3 gene was PCR amplified using primers SC3.fw2 (5′-CGG TCT CTA ATT CTT GGT GGC CAC CCG GGC ACG (SEQ ID NO: 11)) and SC3.rev2 (5′-CGG TCT CTA GCT CTT AGA GGA TGT TGA TGG GGG TGC (SEQ ID NO: 12)) with cDNA isolated from Schizophyllum commune as a template. The PCR product was purified with the Roche PCR-isolation kit. The vector pNG-NisL was digested with EcoRI and HindIII. The PCR product was cut with Eco31I (nucleotides 2-6 in the primer sequences) to generate EcoRI and HindIII sticky ends (at nucleotides 9-12 in the primer sequences). The two fragments were ligated and fused in the resulting plasmid, pNG-NisL-SC3, SC3, in frame, downstream from the NisA leader peptide and the c-myc epitope.
Plasmid pNG-NisT (Example 1) and pNG-NisL-SC3 were established together in L. lactis strain NZ9000 by Electroporation (Holo and Nes, 1995, Methods Mol. Biol. 47: 195-199). Expression was induced and secreted peptides were purified as described in Example 1. MALDI-TOFMS analysis was performed as described in Example 1 with the following modifications: 7 shots instead of 15 and suppression at 1,000 instead of 500. The same was performed for the control strains NZ9000, NZ9000(pNG-nisl-SC3).
Results. Culture-supernatants of the following induced cultures were analyzed by MALDI-TOFMS:

    
    
        A. NZ9000;
        B. NZ9000(pNG-NisL-SC3); and
        C. NZ9000(pNG-NisL-SC3+pNG-nisT).
    
    


No peaks were observed in samples derived from cultures A and B. In sample C, the main peaks correspond to SC3, but are about 2351 Da larger mass, which corresponds to the mass of the NisA leader peptide. This shows that the eukaryotic SC3 preceded by the nisin A leader peptide is secreted by L. lactis via the nisin transporter NisT.
EXAMPLE 3
Export of nisin prepeptide across the cytoplasmic membrane of Escherichia Coli protease-deficient SF120 (Gram-negative bacterium), via the nisin transporter NisT.
Materials and methods. NisT was cloned in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E. coli SF120 (Baneyx, F., and Georiou, G. 1991, J. Bacteriol. 173, 2696-2703). nisA was cloned in a second plasmid with a different antibiotic marker and transformed to the above strain. The resulting strain, as well as a control strain without pBAD-NisT, was grown and induced overnight with 0.3% arabinose and/or another adequate signal. The cells were pelleted and washed in milliQ to disrupting the outer membrane. The cells were pelleted and the supernatant was subjected to ZIPTIPPINGTM and MALDI-TOFMS as in Example 1.
Results. A mass spectrometry signal was identical to Example 1, which is consistent with export of the nisin prepeptide across the cytoplasmic membrane in the strain with both plasmids, NisT and NisA.
EXAMPLE 4A
Export of nisin prepeptide across the cytoplasmic membrane of Escherichia Coli protease-deficient SF120 (Gram-negative bacterium) via the nisin transporter NisT and dehydration by NisB.
The nisin prepeptide includes a leader (SEQ ID NO: 13). Neither serines nor threonines are dehydrated in the leader. The second part of the prepeptide is the nisin propeptide (SEQ ID NO: 14). Most of the serines and all threonines can be dehydrated by NisB.
Materials and methods. NisBT is cloned in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E. coli SF120. NisA is cloned in a second plasmid with a different antibiotic marker and transformed to the above strain. The resulting two-plasmid strains, as well as a control strain without pBAD-NisBT were grown and induced overnight with 0.3% arabinose and/or another adequate signal. The cells are pelleted and washed in milliQ and the outer membrane was disrupted. The cells were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS as performed in example 1.
Results. A mass consistent with the export of the nisin prepeptide, with dehydrated serines and threonines in the propeptide region, across the cytoplasmic membrane in the strain with both plasmids (NisBT and NisA).
EXAMPLE 4B
Export of nisin prepeptide across the cytoplasmic membrane of Escherichia coli protease-deficient SF120 (Gram-negative bacterium) via the nisin transporter NisT and dehydration by NisB.
Materials and methods. NisABT was cloned with an inverted repeat between NisA and NisB, an organization as on the chromosome of L. lactris NZ9700, in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E. coli SF120. The cells were grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate signal. The cells were pelleted and washed in milliQ to disrupt the outer membrane. The cells were pelleted and the supernatant is subjected to ziptipping and MALDI-TOFMS as in Example 1.
Results. A mass consistent with the export of the nisin prepeptide across the cytoplasmic membrane is present, with in the propeptide region most serines and all threonines dehydrated.
EXAMPLE 5
Export of nisin leader coupled to mature nisin across the cytoplasmic membrane of Escherichia coli protease-deficient SF120 (Gram-negative bacterium) via the nisin transporter NisT.
Materials and methods. NisABTC was cloned with an inverted repeat between NisA and NisB in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E coli SF120. The resulting strain is grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate signal. The cells were pelleted and washed in milliQ and the outer membrane was disrupted. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS as in example 1.
The above ZIPTIPPEDTM material and the crude supernatant is treated after outer membrane disruption with trypsin. This material is applied to the agar well assay to determine antibacterial activity. Also, the capacity of the trypsinated solutions to induce the nisin promoter was tested via the Gus assay (Kuipers et al., 1995, J. Biol. Chem. 270: 27299-27304).
Results. A mass spectrometry signal of about 5690 Da was consistent with export of the nisin prepeptide coupled to mature nisin across the cytoplasmic membrane. Trypsinated samples have antimicrobial activity in the agar well assay and nisin promoter induction capacity. These results show export of the nisin prepeptide which has undergone thioether ring formation, since trypsin cleaves off the leader and liberates the active nisin which has antimicrobial activity and induction capacity.
EXAMPLE 6
Export of alpha neurokinin (Table 1) across the cytoplasmic membrane of Escherichia coli protease-deficient SF120 (Gram-negative bacterium) via the variacin transporter VarT.
VarT has simultaneous transport and leader peptidase activity. As a consequence, export of the fusion protein including a variacin-leader (Table II) and alpha neurokinin (SEQ ID NO: 15) (Table 1) through VarT results in extracellular release of the alpha neurokinin without the leader.
Materials and methods. VarT was cloned in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E coli SF120. A construct with leader variacin preceding neurokinin alpha is cloned in a second plasmid with a different antibiotic marker and transformed to the above strain. The resulting strain, as well as a control strain without pBAD-VarT, is grown and induced overnight with 0.3% arabinose and/or another adequate promoter related signal. The cells were pelleted and washed in milliQ and the outer membrane was disrupt. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS as in Example 1.
Results. A mass spectrometry signal corresponding to alpha neurokinin. This result was consistent with export of alpha neurokinin through VarT.
EXAMPLE 7
Export of glucagon (Table 1) via MutII T out of Saccharomyces cerevisiae (eukaryotic organism).
MutT has simultaneous transport and leader peptidase activity. As a consequence export of the fusion protein including a MutacinII-leader and glucagon through MutT results in extracellular release of glucagon without the leader.
The (C5,S24,C29)-Sequence of glucagon is presented at SEQ ID NO: 16.
Materials and methods. MutT was cloned in a suitable vector and transformed to S. cerevisiae. A construct was cloned with leader mutacinII preceding glucagon in a second plasmid which has a different antibiotic marker and the construct was transformed to the above strain. The resulting strain, as well as a control strain without MutT, was grown and induced overnight with an adequate signal. The cells were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS as in Example 1.
Results. A mass spectrometry signal corresponds to glucagon. This shows that the mutacinII leader drives the export of glucagon out of S. cerevisiae. 
EXAMPLE 8A
Export of nisin prepeptide via the nisin transporter NisT and modification by the nisin dehydrating enzyme NisB without subsequent enzymatic thioether bridge formation.
Materials and methods. NisBT was cloned as described in Example 1 using the primers NisB fw, (5′-CGG TCT CGC ATG ATA AAA AGT TCA TTT AAA GCT CAA CCG TTT TTA GTA AG (SEQ ID NO: 17)) and NisT rev (5′-CGG TCT CTC TAG ATT ATT CAT CAT TAT CCT CAT ATT GCT CTG (SEQ ID NO: 18)).
NZ9000+pNG-NisBT (Cm) were transformed with pNG-NisA (Em). NZ9000+pNG-NisBT+pNG-NisA cells were grown and induced as in Example 1. 50 μM TPEN (N,N,N′,N′-Tetrakis(2-Pyrimidyl)ethylenediamine), a specific zinc chelator, was added to the supernatant and incubated 1 hour under stirring. The supernatant was ziptipped and analyzed by MALDI-TOFMS as performed in Example 1.
Results. A MALDI-TOFMS peak around 5690 Da in the sample derived from the supernatant from NZ9000+pNG-NisBT+pNG-NisA cells was present. Absence of the peak in samples derived from the supernatant of NZ9000+pNG-NisT+pNG-NisA (Example 1), which was consistent with dehydration of most serines and all threonines.
EXAMPLE 8B
Export of nisin prepeptide via the nisin transporter NisT and modification by the nisin dehydrating enzyme NisB without subsequent enzymatic thioether bridge formation.
Materials and methods. The plasmid pNG-NisABT was constructed similar to the organization of the genes in the wild type nisin producer NZ9700, which includes an inverted repeat between the NisA and the NisBT genes. This plasmid was transformed to NZ9000, grown and induced. After induction, NisBT was transcribed in low quantities by limited read through. The supernatant was subjected to TPEN treatment as in Example 8A followed by ziptipping and MALDI-TOFMS as in Example 1.
Results. A MALDI-TOFMS peak present around 5690 was consistent with export of the nisin prepeptide and dehydration of propeptide serines (most) and threonines (all).
EXAMPLE 9
Export of nisin prepeptide via the nisin transporter NisT and modification by the nisin dehydrating enzyme NisB followed by NisC-mediated thioether bridge formation, involving a pNG-NisABTC plasmid.
Materials and methods. The plasmid pNG-NisABTC was constructed similar to the organization of the genes in the wild type nisin producer NZ9700, which included an inverted repeat between the NisA and the NisB. NZ9000+pNG-NisABTC were grown and induced. The supernatant is analyzed as in Example 1. Trypsin treated supernatant was subjected to the agar well assay by pouring the trypsinated supernatant in an agar well and overlaying with a nisin sensitive strain. In addition, the trypsinated supernatant was tested for its capacity to induce the nisin promoter with the Gus assay (Kuipers et al. 1995, J. Biol. Chem. 270:27299-27304).
Results. A peak with a mass corresponding to nisin prepeptide including the unmodifed leader peptide coupled to mature nisin, which has undergone dehydration reactions, and the lanthionine ring formation of nisin. Halos were present in the case of trypsinated supernatant and halos were absent, or significantly smaller, than halos in the case of trypsinated medium or untrypsinated supernatant.
These results were consistent with export of the nisin prepeptide which has undergone lanthionine bridge formation since trypsin cleaves off the leader and liberates active nisin which includes antimicrobial activity and induction capacity.
EXAMPLE 10
Secretion of thioether ring stabilized vasopressin by use of the NisA leader peptide in Lactococcus lactis NZ9800.
Vasopressin (SEQ ID NO: 19) is a 9 amino acid (aa) peptide antidiuretic hormone. It has cysteines in position 1 and 6 that form an internal disulfide bond. This example involves ring formation by interaction between aa1 and aa6 through the use of the nisin modification system that forms thioether bridges between a dehydrated serine or threonine and a downstream located cysteine. Conversion of the cysteine at position 1 by genetic modification into a serine enables thioether ring formation by the nisin modifying lantibiotic enzymes. This example involves a precise fusion of serine altered vasopressin (SerVaso) to the NisA leader peptide by genetic modification. The lactococcal strain NZ9800 (Kuipers et al. 1993, Eur. J. Biochem. 216, 281-291), used for expression of the leader peptide-Servaso fusion, contains all the components for the nisin secretion and modification machinery, but lacks the NisA structural gene.
Materials and methods. To obtain a precise and “in frame” fusion of SerVaso with the NisA leader peptide, a first plasmid pNG-NisL-SC3 (example 2) was converted into a general NisA leader peptide secretion vector. Suitable restriction sites were introduced and the c-myc-SC3 sequences were removed by PCR amplification of the entire plasmid using the following primers: pLP.1 (5′-CGG TCT CAG CGT GGT GAT GCA CCT GAA TC (SEQ ID NO: 20)) and pLP.2 (5′-CCA CGC TGA GAC CGC AGC TGG GAT CCG GCT TGA AAC GTT CAA TTG AAA TGG (SEQ ID NO: 21)). The PCR product was cut with Eco31I (nucleotides 2-7 in pLP.1 and nucleotides 8-13 in pLP.2), resulting in sticky ends (neucleotides 9-12 in pLP.1 and nucleotides 3-6 in pLP.2) that are compatible for self-ligation of the plasmid. After self-ligation, the resulting plasmid, pLP1, can be used for precise fusion of peptides and proteins after the . . . GASPR aa sequence of the NisA leader peptide by using the Eco31I restriction site. DNA fragments to be inserted at this position should contain a 5′-ACGC sticky end to allow ligation. At the 3′-end, the DNA fragment should contain a sticky end that is compatible with BamHI (site introduced by primer pLP.2, indicated in bold).
The SerVaso gene was obtained by annealing two oligo's: VP.1: 5′-ACG CTC ATA TTT TCA AAA TTG TCC TCG TGG TTA AG (SEQ ID NO: 22) and VP.2: 5′-GAT CCT TAA CCA CGA GGA CAA TTT TGA AAA TAT GA (SEQ ID NO: 23). The annealed fragment includes a stop codon and has the ACGC overhang at its 5′-end and a BamHI compatible sticky end at the 3′-end. The SerVaso gene fragment was ligated into Eco31I and BamHI digested pLP1 and the resulting plasmid was designated pLP1vp.
Strain NZ9800 carrying pLPvp was induced for expression as described in Example 1. The secreted peptide is purified and analyzed using MALDI-TOFMS (linear mode) essentially as described in Example 1.
Results. A MALDI-TOFMS mass consistent with production of processed and thioether ring modified vasopressin.
EXAMPLE 11
EpilancinBC-mediated synthesis by Staphylococcus epidermis (prokaryote, Gram-positive) of epilancin leader (Table 2) coupled to glucagon (Table 1) with thioether rings.
The (C5, S24, C29)-sequence of glucagon (SEQ ID NO: 16) (Table 1) allows the epilancin K7 enzymes to form thioether rings between S2-C5 and S24-C29.
Materials and methods. A construct leader epilancin K7 was cloned and followed in an open reading frame mutant glucagon. A plasmid with the above construct is transformed to wild type epilancin K7-producing Staphylococcus epidermis. Transcription of the leader-glucagon reading frame is induced. Overnight cell growth in minimal medium was performed, and the cells were centrifuged and ziptipping of the supernatant and MALDI-TOFMS analysis were performed (linear mode).
Results. A MALDI-TOFMS peak consistent with production of glucagon with dehydrated serines and threonines and thioether rings as indicated in Table 1 is present.
EXAMPLE 12
Production by Streptococcus Salivarius (prokaryote Gram-positive) of (S3, S12) tachyplesin I (Table 1) following export via SalT.
Materials and methods. A construct salivaricin-leader (Table 2) was cloned and followed in an open reading frame by mutant tachyplesin (Table 1). SalivaricinT was cloned on a second plasmid with a different antibiotic marker. Both plasmids were transformed to a Streptococcus salivarius strain devoid of salivaricin genes. Transcription of both plasmids was induced during 2-4 hours of continued growth. Every 30 min, 0.2 mM pmsf (protease inhibitor) was added. Ziptipping was performed as in Example 1 and analyzed by MALDI-TOFMS (linear mode).
Results. A mass spectrometry peak was present which corresponds to tachyplesin.
EXAMPLE 13A
Production by Streptococcus salivarius (prokaryote Gram-positive) of (S3, S12) tachyplesinI (Table 1) with salivaricinB-dehydrated Serine-3 and serine-12 without subsequent enzymatic thioether ring formation.
The (S3,S12) sequence of Tachyplesin can be found at SEQ ID NO: 24.
Materials and methods. A construct salivaricin leader (Table 2) was cloned and followed in an open reading frame by mutant tachyplesin (Table 1). SalivaricinBT was cloned on a second plasmid with a different antibiotic marker. This plasmid was transformed to a Streptococcus salivarius strain devoid of salivaricin genes. Transcription of both plasmids was induced during 2-4 hours of continued growth and ziptipping was performed as in Example 1 and analyzed by MALDI-TOFMS (linear mode).
Results. A mass spectrometry peak corresponding to tachyplesin with dehydrated serines was present.
EXAMPLE 13B
Production by Streptococcus salivarius (prokaryote Gram-positive) (S3, S12) tachyplesinI (Table 1) with salivaricinB-dehydrated S3 and S12 without Subsequent Enzymatic Thioether Ring Formation.
The (S3,S12) sequence of Tachyplesin can be found at SEQ ID NO: 24.
Materials and methods. A construct salivaricin-leader (Table 2) was cloned and followed in an open reading frame by mutant tachyplesin (Table 1) including an inverted repeat and, thereafter, salivaricinBT. This plasmid was transformed to a Streptococcus salivarius strain devoid of salivaricin genes. Transcription was induced during 2-4 hours of continued growth and ziptipping was performed as in Example 1 and analyzed by MALDI-TOFMS (linear mode).
Results. A mass spectrometry peak corresponding to tachyplesin with dehydrated serines was present.
EXAMPLE 14
Production by Streptococcus salivarius (prokaryote Gram-positive) of salivaricinBC-modified (S3, S12) tachyplesinI (Table 1) with salivaricinBC-mediated thioether rings instead of disulfide bridges.
The (S3,S12) sequence of Tachyplesin can be found at SEQ ID NO: 24.
This sequence allows the salivaricin enzymes to form thioether rings between S3-C7 and S12-C16.
Materials and methods. A construct salivaricin-leader (Table 2) was cloned and followed in an open reading frame by mutant tachyplesin (Table 1). A plasmid was transformed with the above construct into a wild type salivaricin producing Streptococcus salivarius (prokaryote Gram positive). Transcription of the salivaricin-leader-tachyplesin reading frame was induced during 2-4 hours of continued growth in minimal medium. The cells were centrifuged and ziptipping of the supernatant is performed as in Example 1 and MALDI-TOFMS analyzed (linear mode).
Results. A mass spectrometry peak corresponding to tachyplesin with thioether rings was present.
EXAMPLE 15
Production by Lactococcus lactis (prokaryote, Gram-positive) via lacticinT of vasonatrin (Table 1) without modifications.
Lacticin 481-T has leader peptidase activity and, thus, in this particular example, the supernatant of the cell culture vasonatrin is found without leader. Vasonatrin (SEQ ID NO :25) is amongst others involved in vaso relaxation.
Materials and methods. A construct lacticin 481-leader (Table 2) was cloned and followed in an open reading frame by vasonatrin (Table 1). Lacticin 481-T was cloned on a second plasmid having a different antibiotic marker. Both plasmids were transformed to a L. Lactis strain devoid of lacticin 481 genes. Transcription of both plasmids was induced during overnight growth in minimal medium and ziptipping was performed as in Example 1 and analyzed by MALDI-TOFMS (linear mode).
Results. A mass spectrometry peak corresponding to vasonatrin was present.
EXAMPLE 16
Production by Lactococcus lactis (prokaryote, Gram-positive) via lacticinT of vasonatrin (Table 1), with lacticinM mediated thioether rings.
Vasonatrin (SEQ ID NO: 25) is amongst others involved in vaso relaxation. It has an amino acid sequence that without mutations permits the formation of two lanthionine rings. The lanthionine rings can be formed from S3-C6 and from S16-C22.
Materials and methods. A construct lacticin 481-leader (Table 2) was cloned and followed in an open reading frame by vasonatrin (Table 1). The plasmid was transformed to a wild type lacticin 481 producing strain and transcription of the plasmid was induced during overnight growth in minimal medium. Ziptipping was performed as in Example 1 and analyzed by MALDI-TOFMS (reflectron mode).
Results. A mass spectrometry peak corresponding to vasonatrin with two thioether rings and two more dehydrated serines.
EXAMPLE 17
Production by Escherichia coli SF120 (prokaryote, Gram-negative) of epilancin K7 leader (Table 2) coupled to HIV (gp41) antigenic peptide 1 (SEQ ID NO: 26) (Table 1) without modifications.
Materials and methods. EpilancinT was cloned in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E coli SF120. A construct with epilancin leader preceding HIV (gp41) antigenic peptide 1 was cloned in a second plasmid having a different antibiotic marker and transformed to the above strain. The resulting strain with the two plasmids and a control strain without pBAD-varT was grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate promoter related signal. The cells were pelleted and washed in milliQ and the outer membrane was disrupted. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the epilancin leader coupled to HIV (gp41) antigenic peptide 1.
EXAMPLE 18A
Production by E. coli SF120 (prokaryote, Gram negative) of epilancin K7 leader (Table 2) coupled to HIV (gp41) antigenic peptide 1 (Table 1) with an epilancinB-dehydrated S2, without subsequent epilancinC-mediated thioether ring formation.
The sequence of HIV (gp41) antigenic peptide 1 can be found at SEQ ID NO: 26.
Materials and methods. EpilancinBT was cloned in a suitable vector, such as the pBAD vector, and transformed at 25° C. to E coli SF120. A construct with epilancin leader preceding HIV (gp41) antigenic peptide 1 was cloned in a second plasmid having a different antibiotic marker and transformed to the above strain. The resulting strain at and a control strain without pBAD-varBT were grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate-promoter related signal. The cells were pelleted and washed in milliQ prior to disruption of the outer membrane. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodified epilancin leader coupled to HIV (gp41) antigenic peptide 1, with dehydrated serines and threonines.
EXAMPLE 18B
Production by E. coli SF120 (prokaryote, Gram negative) of epilancin K7 leader (Table 2) coupled to HIV (gp41) antigenic peptide 1 (SEQ ID NO: 26) (Table 1) with an EpilancinB-dehydrated S2, without subsequent epilancinC-Mediated thioether ring formation.
Materials and methods. A plasmid, such as pBAD or another suitable vector, with epilancin-leader preceding HIV (gp41) antigenic peptide 1, preceding an inverted repeat, and preceding epilancinBT was constructed and transformed at 25° C. to E coli SF120. The resulting strain and a control strain without plasmid were grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate promoter related signal. The cells were pelleted and washed in milliQ and the outer membrane was disrupted. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodified epilancin leader coupled to HIV (gp41) antigenic peptide 1 with dehydrated serines and threonines was present.
EXAMPLE 19
Production by E. coli SF120 (prokaryote, Gram negative) of epilancin K7 leader (Table 2) coupled to HIV (gp41) antigenic peptide 1 (Table 1) with an EpilancinBC synthesized thioether ring.
HIV (gp41) antigenic peptide 1 (SEQ ID NO: 26) sequence allows the epilancin enzymes formation of the thioether ring S2-C8.
Materials and methods. A plasmid such as pBAD, or another suitable vector, with epilancin leader preceding HIV (gp41) antigenic peptide 1, preceding an inverted repeat, and preceding EpilancinBTC was cloned and transformed at 25° C. to E. coli SF120. The resulting strain and a control strain without plasmid were grown at 25° C. and induced overnight with 0.3% arabinose and/or another adequate promoter-related signal. The cells were pelleted and washed in milliQ prior to disrupting the outer membrane. The cells remnants were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodified epilancin leader part coupled to modified HIV (gp41) antigenic peptide 1 with one thioether ring and dehydrated serines and threonines.
EXAMPLE 20
Production by S. cerevisiae (eukaryote) of epicidium leader (Table 2) coupled to (S1) calcitonin (Table 1) via EpicidiumT without modifications.
The (S1)-sequence of calcitonin can be found at SEQ ID NO: 27.
Materials and methods. EpicidiumT was cloned in a suitable vector and transformed to Saccharomyces cerevisiae. A construct with epicidium leader preceding calcitonin (Table 1) was cloned in a second plasmid having a different antibiotic marker and transformed to the above strain. The resulting strain and a control strain without epicidiumT were grown and induced overnight with an adequate promoter related signal in the presence of a 2 times added mixture of protease inhibitors. The cells were pelleted and t the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the epicidium leader coupled to calcitonin.
EXAMPLE 21A
Production by S. cerevisiae of epicidium leader (Table 2) coupled to (S1) calcitonin (Table 1) with EpicidumB-dehydrated serines and threonines without enzymatic thioether ring formation.
The (S1)-sequence of calcitonin can be found at SEQ ID NO: 27.
Materials and methods. EpicidiumBT was cloned in a suitable vector and transformed to Saccharomyces cerevisiae. A construct with epicidium leader preceding calcitonin (Table 1) was cloned in a second plasmid having a different antibiotic marker and transformed to the above strain. The resulting strain and a control strain without EpicidiumT were grown and induced overnight with an adequate promoter-related signal in the presence of a 2 times added mixture of protease inhibitors. The cells were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodifed epicidium leader coupled to modified calcitonin with dehydrated serines and threonines.
EXAMPLE 21B
Production by Saccharomyces cerevisiae (eukaryote) of epicidium leader (Table2) coupled to (S1) calcitonin (Table 1) with EpicidiumB-dehydrated serines and threonines without enzymatic thioether ring formation to cys7.
Materials and methods. A construct with epicidium leader preceding calcitonin preceding a stop triplet preceding EpicidiumBT was cloned in a suitable plasmid and transformed to S. cerevisiae. The resulting strain was grown and induced overnight with an adequate promoter-related signal in the presence of a 2 times added mixture of protease inhibitors. The cells were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodified epicidium leader coupled to modified calcitonin with dehydrated serines and threonines was present.
EXAMPLE 22
Production by S. cerevisiae of epicidium leader (Table 2) coupled to (S1) calcitonin (Table 1) with dehydrated serines and threonines and one EpicidiumBC-mediated thioether ring. The (S1)-sequence of calcitonin (SEQ ID NO: 27) allows the epicidium enzymes to form the lanthionine S1-C7.
Materials and methods. A construct with epicidium-leader preceding calcitonin preceding a stop triplet preceding EpicidiumBTC was inserted in a suitable plasmid and transformed to Saccharomyces cerevisiae. The resulting strain was grown and induced overnight with an adequate promoter-related signal. The cells were pelleted and the supernatant was subjected to ziptipping and MALDI-TOFMS (linear mode) as in Example 1.
Results. A mass spectrometry signal corresponding to the unmodified epicidium leader coupled to modified calcitonin with dehydrated serines and threonines and one thioether ring was present.
EXAMPLE 23
Secretion of thioether ring stabilized (L7C)LHRH by use of the NisA leader peptide in Lactococcus lactis NZ9700.
L7C-LHRH (luteinizing hormone release hormone) is a 10-amino acid (aa) peptide. Replacing the leucine at position 7 with a cysteine enables thioether ring formation by the nisin modifying lantibiotic enzymes. These modifying enzymes form a complex with the transporter NisT and the modifications are coupled to transport. Therefore, the (poly)peptide to be modified should be preceded by the nisin leader which directs the fusion peptide to the nisin transporter. This example involves the precise fusion of L7C-LHRH to the nisin leader peptide by genetic modification. The lactococcal strain NZ9700 (a nisin producing L. lactis strain; Kuipers et al. 1997, Tibtech. 15: 135-140) is used for expression of the leader peptide-(L7C)LHRH fusion and contains the components for the nisin secretion (NisT) and modification machinery (NisB and NisC). The enzyme NisB dehydrates serine at position 4 and the dehydrated residue is coupled to the cysteine of position 7 by enzyme NisC to form a thioether bridge.
Materials and methods. A pNZ8048-derived plasmid (Kuipers et al. 1997, Tibtech. 15:135-140) was used for the nisin inducible expression of (L7C)LHRH preceded by the nisin leader in Lactococcus lactis. The plasmid, termed pLP1, was constructed in such a way that precise fusion of peptides and proteins after the . . . GASPR aa sequence of the NisA leader peptide by making use of an Eco31I restriction site. DNA fragments to be inserted at this position should contain a 5′-ACGC sticky end to allow ligation. The DNA fragment should contain a sticky end at the 3′-end that is compatible with BamHI.
The (L7C)LHRH gene is obtained by annealing two oligo's: LHRH1: 5′-A CGC CAA CAC TGG TCA TAT GGT TGT CGT CCT GGT TAA G (SEQ ID NO: 28) and LHRH2: 5′-GA TCC TTA ACC AGG ACG ACA ACC ATA TGA CCA GTG TTG (SEQ ID NO: 29). The annealed fragment includes a stop codon and includes the ACGC overhang at the 5′-end and a BamHI compatible sticky end at the 3′-end. The (L7C)LHRH gene fragment is ligated into Eco31I and BamHI and digested pLP1 and the resulting plasmid is designated pLP1-LHRH1.
The vector pLP1-LHRH1 is transformed to Lactococcus lactis NZ9700 (a nisin producing L. lactis strain; Kuipers et al. 1997, Tibtech. 15: 135-140). The resulting NZ9700+pLP1-LHRH1 was grown in M17-based medium (Terzaghi and Sandine, 1975, Appl. Microbiol. 29: 807-813) to an OD600 of 0.4. The cells were collected by centrifugation and resuspended in the same volume of Minimal Medium (Jensen and Hammer, 1993, Appl. Environ. Microbiol. 59: 4363-4366). After overnight incubation and subsequent centrifugation, samples were prepared using C18 ziptips (Millipore) as follows: pipet two times with 10 μl 50% acetonitril, followed by two times with 10 μl milliQ water, followed by eight times with 10 μl supernatant, followed by two times washing with 10 μl MilliQ water, followed by elution two times with 10 μl 50% acetonitril containing 0.1% TFA. The final eluent is vacuum dried and stored at −20° C. until analysis by mass spectrometry. Prior to analysis, the dry material was resuspended in 6 μl of 50% acetonitril containing 0.1% TFA and 1 μl was applied to the target. After drying, 1 μl of matrix (10 mg/ml alpha-cyano-4-hydroxycinnamic acid completely dissolved (by mildly heating and vortexing) in 50% acetonitril containing 0.1% TFA) was applied to the target. The following MALDI-TOFMS (linear mode) laser settings were used: 100% coarse energy, 90% fine, source 20 KV, extra 19800, force 15000, suppression 350, pulse time 40, pulse voltage 1400, sampling rate 500 MHz, sensitivity 50 mV, shots 15.
EXAMPLE 24
This Example Describes the Production of a Lantibiotic with the leader peptide still attached to it by using a strain that does not express the leader peptidase. In the case of some novel lanthionine containing (poly)peptides, this provides the advantage of reduced toxicity of the novel lantibiotic towards the producer cell.
Materials and methods. A ΔNisP strain from Lactococcus lactis NZ9700 is constructed.
A delta NisP strain is made using the plasmid pOR1280 (Leenhouts et al., 1996, Mol. Gen. Genet. 253, 217-224.). This disruption of NisP is made by removing the start codon of the coding gene. The advantage is the absence of the whole protein without a major alteration of the mRNA. Two PCR products of about 1 Kb were generated wherein one product starts before the gene ending before the mutated start codon and the second product starts from the start codon. These PCR products were coupled by a second PCR reaction and cloned in the pOR1280 vector in the multiple cloning site. The result was a 2 Kb genomic fragment with the changed stop codon in the middle. Finally, two subsequent single crossovers transfer the mutation into the genome.
Sequence around start codon NisP: 




The amino acid sequence at SEQ ID NO: 31 is one possible open reading frame of NisP beginning at position 27 of the NisP nucleotide sequence above and ending at position 71.
The priming sites are nucleotides 38-65 and 74-99, the start codon is shown in bold face and the boxed area is replaced by NotI restriction site in the mutant strain.
The following primers are used dnisp1:

    
    
        5′-cggtctctctagacctcctgattatgacgtgattg-3′ (SEQ ID NO: 32)
        Eco31I site is at nucleotides 2-6; XbaI site is at nucleotides 8-13.
    
    


dnisp2:

    
    
        5′-gtagcgggacctctagtttcctaccttcgttgc-3′ (SEQ ID NO: 33)
        NotI site at nucleotides 4-11; changed start codon (into stop codon) at nucleotides 12-14.
    
    


dnisp3:

    
    
        5′-gtagcggccgcactaggtttcctttttatcgtttgttcg-3′ (SEQ ID NO: 34)
        NotI site at nucleotides 4-11.
    
    


dnisp4:

    
    
        5′-cggtctctagatctccataaacatattggtaccagccag-3′ (SEQ ID NO: 35)
        Eco31I site at nucleotides 2-7; BglII site at nucleotides 8-13.
    
    


Two separate PCRs were performed on chromosomal DNA of the NZ9700 strain. One PCR was performed with primers dnisp1 and dnisp2 to form product of about 1.5 kb in length. A second PCR was performed with primers dnisp3 and dnisp4 to form a product of about 1.5 kb. Both fragments were purified and digested with NotI. The fragments were ligated together and a third PCR was performed on the ligation mixture with primers dnisp1 and dnisp4 to form a product of about 3 kb.
The product was digested with Eco31I or BglII/XbaI and cloned in pOR1280. The plasmid was transformed to L. lactis NZ9700 and growth was selected on erythromycin plates. Specific insertions into NisP gene (PCR, decrease in nisin production) were positively identified by growing a colony for 36 generations, plating out on X-gal/IPTG plates and screening for white colonies. The white colonies should be sensitive to erythromycin and be hampered in nisin production (no or small halo formation). The produced nisin should contain the leader sequence attached to the nisin.
The mutation was checked by PCR and sequencing. The above-generated ΔNisP strain was grown overnight in M17 medium (Terzaghi and Sandine, 1975, Appl. Microbiol. 29: 807-813), diluted 100 fold and grown to OD600 equal to 0.4. Subsequently, the cells were pelleted and resuspended in minimal medium (Jensen and Hammer, 1993, Appl. Environ. Microbiol. 59: 4363-4366) supplemented with protease inhibitors 0.2 mM pmsf, 0.2 mM TPCK and filtered supernatant of the nisin producing L. lactis NZ9700 at 1000 fold dilution. After 1, 2 and 3 hours, more 0.2 mM pmsf, 0.2 mM TPCK are added and followed by overnight incubation. The cells were pelleted and the supernatant of the samples was subjected to: a) ziptipping as in described Example 1 and analyzed by MALDI-TOFMS using the settings given in Example 1; b) treatment with leader peptidase or trypsin and followed by either ziptipping and MALDI-TOFMS, or a halo assay; or c) binding to a column with antibodies against the nisin leader peptide. Elution and experiments a) and b).
Results: a) a mass spectrometry signal consistent with nisin (with all its thioether rings) to which the leader is still attached was present; b) a nisin mass spectrometry signal was present or halo formation by the samples treated by leader peptidase or trypsin was observed; and c) results as under a) and b) respectively.
EXAMPLE 25
Growth medium. When analyzing peptide and protein samples by mass spectrometry, the purity of the samples is a major issue. Contamination of the sample may drastically decrease the detection level of peptides and proteins. In order to prepare samples that have a relatively high purity and allow an optimal sensitivity when measuring exported peptides and proteins by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOFMS), bacterial cells are grown in a very poor medium. The poor medium essentially contains a mixture of specific salts, specific vitamins, glucose, asparagine and casamino acids. The medium does not contain: trypton, soya peptone, meat digest or yeast extract.
The following minimal medium can be prepared for use with Lactococci:
Stock solutions:















SOLUTION A










(NH4)2SO4
  2.0 g;



Na2HPO4
  6.0 g;



KH2PO4
  3.0 g;



Na2SO4
 0.011 g; and



NaCl
   1.0 g are dissolved in 200 ml H2O.



SOLUTION B



Casamino acids
 10.0 g;



Na-acetate
  2.0 g;



Asparagine
 0.08 g;



MgCl2
  0.2 g;



CaCl2
 0.01 g; and



FeCl3(7H2O)
0.0006 g are dissolved in 800 ml H2O.



GLUCOSE 20%



Glucose
   20 g is dissolved in 100 ml H2O.



VITAMIN MIX



biotin
 0.01 g;



folic acid
  0.1 g;



riboflavin
  0.1 g;



nicotinic acid
  0.1 g;



pantotheic acid
  0.1 g; and



pyridoxal
  0.2 g are dissolved in 100 ml H2O.










Solution A, B and the glucose solution are autoclaved separately, while the vitamin mix is filter sterilized.
To prepare 100 ml of medium, after sterilization (and cooling down), 20 ml of solution A is added to 80 ml of solution B, 2.5 ml glucose 20% is added and 100 ul of vitamin mix is added. If necessary, appropriate antibiotics are added.
EXAMPLE 26
Purification of peptides and proteins from minimal culture medium. Peptide and protein samples for analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOFMS) was prepared as follows. Cultures of bacteria grown in minimal medium were centrifuged in order to pellet the cells. The supernatant was aspirated and dispensed several times into and out of a pipet tip that contains a microvolume bed of affinity chromatography media fixed at the end of the tip that is without dead volume. This procedure has been referred to herein as “ziptipping.” A washing step follows in order to wash away contaminants and unwanted biomolecules. The washing step was performed by aspirating and dispensing, for instance, milliQ water. Finally, the peptide or protein was eluted in 1-20 μl of suitable solvent and applied directly on the target, or vial, or speedvacced and stored at −20° C. Prior to MALDI TOFMS analysis, the sample was resuspended in 1 to 5 μl (or further dilution) of a suitable solvent of which 1 μl was applied on the target or vial.
Table 1: (poly)peptides of which the coding DNA is preceded by lantibiotic leader coding DNA in an open reading frame. Mutation possibilities allowing posttranslational thioether ring(s) formation given, for example, for vasopressin applies also to other sequences, including those which have already one ring, within other (poly)peptides in Table 1, taking into account the description of thioether ring formation mentioned in the text.







TABLE 1A





Vasopressin: Function: as an antidiuretic hormone:















(S1, R8)-sequence (SEQ ID NO: 36); lanthionine ring S1-C6


(S1, C2, R8)-sequence (SEQ ID NO: 37); lanthionine ring S1-C2


(S1, C3, R8)-sequence (SEQ ID NO: 38); lanthionine ring S1-C3


(S1, C4, R8)-sequence (SEQ ID NO: 39); lanthionine ring S1-C4


(S1, C5, R8)-sequence (SEQ ID NO: 40); lanthionine ring S1-C5


(S1, A6, C7, R8)-sequence (SEQ ID NO: 41); lanthionine ring S1-C7


(S1, A6, C8)-sequence (SEQ ID NO: 42); lanthionine ring S1-C8


(S1, R8, C9)-sequence (SEQ ID NO: 43); lanthionine ring S1-C9


(A1, S2, R8)-sequence (SEQ ID NO: 44); lanthionine ring S2-C6


(A1, S2, C3, R8)-sequence (SEQ ID NO: 45); lanthionine ring S2-C3


(A1, S2, C4, R8)-sequence (SEQ ID NO: 46); lanthionine ring S2-C4


(A1, S2, C5, R8)-sequence (SEQ ID NO: 47); lanthionine ring S2-C5


(A1, S2, A6, C7, R8)-sequence (SEQ ID NO: 48); lanthionine ring S2-C7


(A1, S2, A6, C8)-sequence (SEQ ID NO: 49); lanthionine ring S2-C8


(A1, S2, A6, R8, C9)-sequence (SEQ ID NO: 50); lanthionine ring S2-C9


(A1, S3, R8)-sequence (SEQ ID NO: 51); lanthionine ring S3-C6


(A1, S3, C4, R8)-sequence (SEQ ID NO: 52); lanthionine ring S3-C4


(A1, S3, C5, R8)-sequence (SEQ ID NO: 53); lanthionine ring S3-C5


(A1, S3, A6, C7, R8)-sequence (SEQ ID NO: 54); lanthionine ring S3-C7


(A1, S3, A6, C8)-sequence (SEQ ID NO: 55); lanthionine ring S3-C8


(A1, S3, A6, R8, C9)-sequence (SEQ ID NO: 56); lanthionine ring S3-C9


(A1, S4, R8)-sequence (SEQ ID NO: 57); lanthionine ring S4-C6


(A1, S4, C5, R8)-sequence (SEQ ID NO: 58); lanthionine ring S4-C5


(A1, S4, A6, C7, R8)-sequence (SEQ ID NO: 59); lanthionine ring S4-C7


(A1, S4, A6, C8)-sequence (SEQ ID NO: 60); lanthionine ring S4-C8


(A1, S4, A6, R8, C9)-sequence (SEQ ID NO: 61); lanthionine ring S4-C9


(A1, S5, R8)-sequence (SEQ ID NO: 62); lanthionine ring S5-C6


(A1, S5, A6, C7, R8)-sequence (SEQ ID NO: 63); lanthionine ring S5-C7


(A1, S5, A6, C8)-sequence (SEQ ID NO: 64); lanthionine ring S5-C8


(A1, S5, A6, R8, C9)-sequence (SEQ ID NO: 65); lanthionine ring S5-C9


(A1, S6, C7, R8)-sequence (SEQ ID NO: 66); lanthionine ring S6-C7


(A1, S6, C8)-sequence (SEQ ID NO: 67); lanthionine ring S6-C8


(A1, S6, R8, C9)-sequence (SEQ ID NO: 68); lanthionine ring S6-C9


(A1, S7, C8)-sequence (SEQ ID NO: 69); lanthionine ring S7-C8


(A1, S7, R8, C9)-sequence (SEQ ID NO: 70); lanthionine ring S7-C9


(A1, S7, C9)-sequence (SEQ ID NO: 71); lanthionine ring S8-C9.









Terlipressin (antidiuretic hormone):

    
    
        S4-Sequence (SEQ ID NO: 72)
        Posttranslational lanthionine: S4-C9.
    
    


Cispressin (antidiuretic hormone):

    
    
        S1-Sequence (SEQ ID NO: 73)
        Posttranslational lanthionine ring: S1-C6.
    
    


Adrenomedullin Hypotensive peptide, may function as a hormone in circulation control

    
    
        A13,S16-Sequence (SEQ ID NO: 74)
        Posttranslational lanthionine: S16-C21.
    
    


Allatostatin I (neuropeptide inhibitor of juvenile hormone synthesis)

    
    
        C6-Sequence (SEQ ID NO: 75)
        Posttranslational lanthionine: S3-C6.
    
    


Angiotensin I

    
    
        S7,C10-Sequence (SEQ ID NO: 76)
        Posttranslational lanthionine S7-C10
        Function: In response to lowered pressure, the enzyme renin cleaves angiotensin I, from angiotensinogen, then removes a dipeptide to yield the physiologically active angiotensin II, the most potent pressor substance known, which helps regulate volume and mineral balance of body fluids.
    
    


Anthopleurin-A (neuropeptide)

    
    
        A4-Sequence (SEQ ID NO: 77)
        Posttranslational lanthionine rings: S3-C6, S27-C31, S33-C38, T44-C48.
    
    


Anti-inflammatory peptide 1 (anti-inflammation)

    
    
        S1,C6-Sequence (SEQ ID NO: 78)
        Posttranslational lanthionine: S1-C6
    
    


Dermaseptin (antimicrobial peptide)

    
    
        C10-Sequence (SEQ ID NO: 79)
        Posttranslational lanthionine: T5-C10.
    
    


Bombinin-like peptide (antimicrobial peptide)

    
    
        C8-Sequence (SEQ ID NO: 80)
        Posttranslational lanthionine: S5-C8.
    
    


Histatin-5 (antimicrobial salivary peptide)

    
    
        S4,C7-Sequence (SEQ ID NO: 81)
        Posttranslational lanthionine: S4-C7.
    
    


Indolicidin (antimicrobial peptide)

    
    
        S2,C5-Sequence (SEQ ID NO: 82)
        Posttranslational lanthionine: S2-C5.
    
    


Magainin-1 (antimicrobial peptide)

    
    
        C13-Sequence (SEQ ID NO: 83)
        Posttranslational lanthionine: S8-C13.
    
    


Atrial Natriuretic Factor (potent vasoactive substance with a key role in cardiovascular homeostasis and cGMP-stimulating activity).

    
    
        (SEQ ID NO: 84)
        Posttranslational lanthionines: S1-C7, S19-C23.
    
    


Bradykinin (important role in renal physiology and behavior).

    
    
        C9-Sequence (SEQ ID NO: 85)
        Posttranslational lanthionine: S6-C9.
    
    


Brain Natriuretic Peptide (acts as a cardiac hormone involved in natriuresis, diuresis, vasorelaxation, inhibition of renin and aldosteron secretion, improves heart function)

    
    
        S16,C19-Sequence (SEQ ID NO: 86)
        Posttranslational lanthionine: S8-C10, S16-C19 
    
    


C-type Natriuretic peptide (exhibits natriuretic and vasodepressor activity)

    
    
        (SEQ ID NO: 87)
        Posttranslational lanthionine ring: S34-C37, S47-C53.
    
    


Vasonatrin peptide (vasorelaxation)

    
    
        (SEQ ID NO: 88)
        Posttranslational lanthionine ring: S3-C6,S17-C22.
    
    


Delta sleep inducing peptide (delta sleep induction)

    
    
        S2,C6-Sequence (SEQ ID NO: 89)
        Posttranslational lanthionine ring: S2-C6.
    
    


Alpha-dendrotoxin

    
    
        S11,S26-Sequence (SEQ ID NO: 90)
        Posttranslational lanthionine: S11-C15, S26-C31
        Function: affects potassium channels.
        Eledoisin
        C4-Sequence (SEQ ID NO: 91)
        Posttranslational lanthionine ring: S2-C4
        Function: neuron excitation, causing behavioral responses, vasodilators, secretagogues, causing contraction of smooth muscles.
    
    


Echistatin

    
    
        (SEQ ID NO: 92)
        Posttranslational lanthionine rings: S4-C7, T18-C20, T36-C37
        Function: Inhibitor of fibrinogen-dependent platelet aggregation.
    
    


alpha-endorphin

    
    
        S2,C6-Sequence (SEQ ID NO: 93)
        Posttranslational lanthionine ring: S2-C6
        Function: opioid.
    
    


beta-endorphin

    
    
        S21,C26-Sequence (SEQ ID NO: 94)
        Posttranslational lanthionine ring: S21-C26
        Function: opioid.
    
    


Defensin I

    
    
        S2,S 12-Sequence (SEQ ID NO: 95)
        Posttranslational lanthionine rings: S2-C4, S13-C19
        Function: antimicrobial peptide.
    
    


Secretin

    
    
        S23,C26-Sequence (SEQ ID NO: 96)
        Posttranslational lanthionine ring:S23-C26
        Function: pH regulation in the stomach.
    
    


Urocortin

    
    
        C19-Sequence (SEQ ID NO: 97)
        Posttranslational lanthionine ring: T16-C19
        Function: stimulates ACTH secretion.
    
    


Urotensin II

    
    
        S5-Sequence (SEQ ID NO: 98)
        Posttranslational lanthionine rings: T3-C6, S5-C11
        Function: osmoregulation and corticotropin release factor.
    
    


Small Cardioactive Peptide A

    
    
        S4,C7-Sequence (SEQ ID NO: 99)
        Posttranslational lanthionine:S4-C7
        Function: inhibits acetylcholine release
    
    


Small Cardioactive peptide B

    
    
        S4,C7-Sequence (SEQ ID NO: 100)
        Posttranslational lanthionine: S4-C7
        Function: stimulates contraction in the gut, increases amplitude of the heart beat.
    
    


Ceratotoxin A

    
    
        C9-Sequence (SEQ ID NO: 101)
        Posttranslational lanthionine: S4-C9
        Function: antimicrobial, hemolytic peptide with activity against Gram-positive and Gram-negative bacteria, stable at 100° C.
    
    


Cerebellin

    
    
        C7-Sequence (SEQ ID NO: 102)
        Posttranslational lanthionine: S3-C7
        Function: neuromudulation, stimulation of norepinephrine release, enhances indirectly adrenocortical secretion.
    
    


Charybdotoxin

    
    
        S33-Sequence (SEQ ID NO: 103)
        Posttranslational (methyl)lanthionine: T3-C7, T8-C13, S15-C17, T23-C28, S33-C35
        Function: inhibitor calcium—and voltage activated potassium channels.
    
    


Cholecystokinin

    
    
        C8-Sequence (SEQ ID NO: 104)
        Posttranslational lanthionine: S4-C8
        Function: Gall bladder contraction and release of pancreatic enzymes in the gut.
    
    


Conopressin G

    
    
        S1-Sequence (SEQ ID NO: 105)
        Posttranslational lanthionine: S1-C6
        Function: behavioral control.
    
    


alpha-Conotoxin EI

    
    
        S2,S5-Sequence (SEQ ID NO: 106)
        Posttranslational lanthionine: S2-C4, S5-C10, S13-C18
        Function: blocking nicotinic acetylcholine receptors.
    
    


Corazonin

    
    
        C9-Sequence (SEQ ID NO: 107)
        Posttranslational lanthionine: S5-C9
        Function: Regulation heart beat.
    
    


Leu-enkephalin

    
    
        S2,C3-Sequence (SEQ ID NO: 108)
        Posttranslational lanthionine ring: S2-C3
        Function: opioid
    
    


Met-enkephalin

    
    
        S2,C3-Sequence (SEQ ID NO: 109)
        Posttranslational lanthionine ring: S2-C3
        Function: opioid.
    
    


Oxytocin

    
    
        (S1)-Sequence (SEQ ID NO: 110)
        Posttranslational lanthionine ring S1-C6
        Function: Oxytocin stimulates uterine contraction and lactation; increases Na+ secretion;
        stimulates myometrial GTPase and phospholipase C.
    
    


Exendin-3

    
    
        C35-Sequence (SEQ ID NO: 111)
        Posttranslational lanthionine ring: S32-C35
        Function: secretin-like.
    
    


Experimental Allergic Encephalitogenic peptide

    
    
        C5-Sequence (SEQ ID NO: 112)
        Posttranslational lanthionine ring: S2-C5
        Function: myelin membrane stabilization.
    
    


Experimental Autoimmune Encephalomyelitis Complementary peptide

    
    
        S4,C7-Sequence (SEQ ID NO: 113)
        Posttranslational lanthionine ring: S4-C7
        Effect: having a role in autoimmune encephalomyelitis.
    
    


GonadoliberinII

    
    
        (C9)-sequence (SEQ ID NO: 114)
        Posttranslational lanthionine ring: S4-C9
        Function: stimulates the secretion of gonadotropins; it stimulates the secretion of both luteinizing and follicle stimulating hormones.
    
    


Tocinoic acid/pressinoic acid

    
    
        (S1,I3)-Sequence (SEQ ID NO: 115)
        posttranslational lanthionine ring S1-C6
        Function: Tocinoic acid is an oxytocin inhibitor, induces maternal behavior.
    
    


Leuprolide

    
    
        Sequences:
        (SEQ ID NO: 116)
        Posttranslational thioether ring: S4-C7
        (SEQ ID NO: 117)
        Posttranslational thioether ring: S4-C7
        Function: LHRH agonist.
    
    


Calcitonin

    
    
        Accession number: P01258
        (S1)-Sequence (SEQ ID NO: 118)
        Posttranslational thioether ring S1-C7
        Function: CaPi incorporation in bones.
    
    


ACTH, Adrenocorticotropic hormone

    
    
        (Q5, C6)-Sequence (SEQ ID NO: 119)
        posttranslational lanthionine ring S1-C6
        Function: ACTH stimulates synthesis and secretion of glucocorticoids by adrenal cortex.
    
    


Corticotropin inhibiting peptide

    
    
        S4,C8-Sequence (SEQ ID NO: 120)
        Posttranslational lanthionine: S4-C8
        Function: inhibition ACTH.
    
    


Corticotropin-Release Factor

    
    
        S30,C33-Sequence (SEQ ID NO: 121)
        Posttranslational lanthionine: S30-C33
        Function: release of corticotrophin.
    
    


Somatostatin

    
    
        (S3)-Sequence (SEQ ID NO: 122)
        posttranslational lanthionine ring S3-C14
        Function:somatotropin release inhibition factor, growth hormone release inhibiting factor.
    
    


Human pancreatic polypeptide

    
    
        (S18, C21)-Sequence (SEQ ID NO: 123)
        Posttranslational lanthionine ring S18-C21
        Function: Agonist at Y4 neuropeptide receptors.
    
    


Peptide YY

    
    
        (S22,C25,T29,C32)-Sequence
        (SEQ ID NO: 124)
        Posttranslational (methyl)lanthionine rings S22-C25, T29-C32
        Function: Gut hormone that inhibits both secretin- and cholecystokinin-stimulated pancreatic secretion.
    
    


Glucagon

    
    
        (C5,S24,C29)-Sequence (SEQ ID NO: 125)
        Posttranslational lanthionine rings S1-C5, S24-C29
        Function: restoring blood glucose level when too low.
    
    


alpha-neurokinin

    
    
        (C9)-sequence (SEQ ID NO: 15)
        posttranslational lanthionine ring S5-C9
        function: tachykinin antagonist.
    
    


LHRH1, Luteinizing Hormone Releasing Hormone

    
    
        Function: regulates secretion of gonadotropins, luteinizing hormone and sex steroids.
        (Q1, C7)-Sequence (SEQ ID NO: 126)
        Posttranslational lanthionine ring S4-C7
    
    
















(S1, C4)-Sequence:
(SEQ ID NO: 127)
posttr. ring: S1-C4


(S1, A4, C5)-Sequence:
(SEQ ID NO: 128)
posttr. ring: S1-C5


(S1, A4, C6)-Sequence:
(SEQ ID NO: 129)
posttr. ring: S1-C6


(Q1, S2, A4, C5)-Sequence:
(SEQ ID NO: 130)
posttr. ring: S2-C5


(Q1, S2, A4, C6)-sequence:
(SEQ ID NO: 131)
posttr. ring: S2-C6


(Q1, S2, A4, C7)-sequence:
(SEQ ID NO: 132)
posttr. ring: S2-C7


(Q1, S3, A4, C6)-sequence:
(SEQ ID NO: 133)
posttr. ring: S3-C6


(Q1, S3, A4, C7)-sequence:
(SEQ ID NO: 134)
posttr. ring: S3-C7


(Q1, S3, A4, C8)-sequence:
(SEQ ID NO: 135)
posttr. ring: S3-C8


(Q1, C8)-sequence:
(SEQ ID NO: 136)
posttr. ring: S4-C8


(Q1, C9)-sequence:
(SEQ ID NO: 137)
posttr. ring: S4-C9


(Q1, A4, S5, C8)-sequence:
(SEQ ID NO: 138)
posttr. ring: S5-C8


(Q1, A4, S5, C9)-sequence:
(SEQ ID NO: 139)
posttr. ring: S5-C9


(Q1, A4, S5, C10)-sequence:
(SEQ ID NO: 140)
posttr. ring: S5-C10


(Q1, A4, S6, C9)-sequence:
(SEQ ID NO: 141)
posttr. ring: S6-C9


(Q1, A4, S6, C10)-sequence:
(SEQ ID NO: 142)
posttr. ring: S6-C10


(Q1, A4, S7, C10)-sequence:
(SEQ ID NO: 143)
posttr. ring: S7-C10.









LHRH2, Luteinizing Hormone Releasing Hormone fragment

    
    
        Function: regulates secretion of gonadotropins, luteinizing hormone and sex steroids.
        (Q1, C7)-Sequence (SEQ ID NO: 309)
        Posttranslational lanthionine ring S4-C7
    
    
















(S1, C4)-Sequence:
   (SEQ ID NO: 144)
posttr. ring: S1-C4


(S1, A4, C5)-Sequence:
(SEQ ID NO: 145)
posttr. ring: S1-C5


(S1, A4, C6)-Sequence:
(SEQ ID NO: 146)
posttr. ring: S1-C6


(Q1, S2, A4, C5)-Sequence:
(SEQ ID NO: 147)
posttr. ring: S2-C5


(Q1, S2, A4, C6)-sequence:
(SEQ ID NO: 148)
posttr. ring: S2-C6


(Q1, S2, A4, C7)-sequenee:
(SEQ ID NO: 149)
posttr. ring: S2-C7


(Q1, S3, A4, C6)-sequence:
(SEQ ID NO: 150)
posttr. ring: S3-C6


(Q1, S3, A4, C7)-sequence:
(SEQ ID NO: 151)
posttr. ring: S3-C7


(Q1, S3, A4, C8)-sequenee:
(SEQ ID NO: 152)
posttr. ring: S3-C8


(Q1, C8)-sequence:
(SEQ ID NO: 153)
posttr. ring: S4-C8


(Q1, C9)-sequence:
(SEQ ID NO: 154)
posttr. ring: S4-C9


(Q1, A4, S5, C8)-sequence:
(SEQ ID NO: 155)
posttr. ring: S5-C8


(Q1, A4, S5, C9)-sequence:
(SEQ ID NO: 156)
posttr. ring: S5-C9


(Q1, A4, S5, C10)-sequence:
(SEQ ID NO: 157)
posttr. ring: S5-C10


(Q1, A4, S6, C9)-sequence:
(SEQ ID NO: 158)
posttr. ring: S6-C9


(Q1, A4, S6, C10)-sequence:
(SEQ ID NO: 159)
posttr. ring: S6-C10


(Q1, A4, S7, C10)-sequence:
(SEQ ID NO: 160)
posttr. ring: S7-C10.









Brain derived acidic fibroblast growth factor (102-111)

    
    
        (S103,C109)-Sequence (SEQ ID NO: 161)
        Posttranslational lanthionine ring S103-C109
        Function: growth factor.
    
    


Brain derived basic fibroblast growth factor (1-24)

    
    
        (SEQ ID NO: 162)
        Posttranslational lanthionine ring S11-C17
        Function: growth factor.
    
    


Insulin

    
    
        Sequences:
        alpha-chain (SEQ ID NO: 163)
        (S9-C14, T27-C30)
        beta chain (SEQ ID NO: 164)
        Posttranslational (methyl)lanthionine rings S9-C14, T27-C30
        disulfide bonds: alpha 6-11 alpha 7-beta 7, alpha 20-beta 19
        function: diabetes treatment.
    
    


Parathormone:

    
    
        (S36-C39, T79-C82)-Sequence (SEQ ID NO: 165)
        Posttranslational (methyl)lanthionine rings S36-C39, T79-C82
        Function: modulation of serum calcium content affecting the mineral and bone physiology.
    
    


Fibrinogen Binding Inhibitor peptide

    
    
        S6,C9-Sequence (SEQ ID NO: 166)
        Posttranslational lanthionine: S6-C9.
    
    


Fibroblast growth factor inhibitory peptide

    
    
        S1,C3-Sequence (SEQ ID NO: 167)
        Posttranslational lanthionine ring: S1-C3
        Effect: inhibition fibroblast growth factor.
    
    


Galanin

    
    
        C10-Sequence (SEQ ID NO: 168)
        Posttranslational lanthionine ring: S6-C10
        Function: contracts smooth muscle of the gastrointestinal and genitourinary tract, regulates growth hormone release, modulates insulin release.
    
    


Gastric Inhibitory Polypeptide

    
    
        S28,C31-Sequence (SEQ ID NO: 169)
        Function: potent stimulation of insulin secretion and relatively poor inhibitor of gastric acid secretion.
    
    


Big Gastrin-I

    
    
        S8,C 11-Sequence (SEQ ID NO: 170)
        Posttranslational lanthionine ring: S8-C11
        Function: stimulates gastric HCl secretion, pancreatic enzyme secretion, smooth muscle contraction and increases blood circulation and water secretion in the stomach and intestine.
    
    


Pentagastrin

    
    
        S1,C4-Sequence (SEQ ID NO: 171)
        Posttranslational lanthionine ring: S1-C4
        Gastrin Releasing Peptide
        S9,C 12-Sequence (SEQ ID NO: 172)
        Posttranslational lanthionine ring: S9-C12
        Function: gastrin release.
    
    


Transforming growth factor alpha

    
    
        (SEQ ID NO: 173)
        Posttranslational (methyl)lanthionine ring: S3-C8, T21-C22, S37-C44
        Function: TGF alpha is a mitogenic polypeptide that is able to bind to the egf receptor and act synergistically with TGF beta to promote anchorage-independent cell proliferation in soft agar.
    
    


Human growth hormone

    
    
        C7-Sequence (SEQ ID NO: 174)
        Posttranslational methyllanthionine ring: T3-C7
        Function: growth hormone, stimulates amongst others protein synthesis and amino acid uptake.
    
    


Growth hormone release factor

    
    
        C22-Sequence (SEQ ID NO: 175)
        Posttranslational lanthionine ring: S18-C22
        Function: release of growth hormone.
    
    


Guanylin

    
    
        (SEQ ID NO: 176)
        Posttranslational lanthionine ring: T3-C4, T13-C15
        Function: activator of guanylate cyclase.
    
    


Helospectin I

    
    
        S15,C 18-Sequence (SEQ ID NO: 177)
        Posttranslational lanthionine ring: S15-C18
        Hepatitis B surface antigen fragment
        C6-Sequence (SEQ ID NO: 178)
        Posttranslational methyllanthionine ring: T3-C6
        Function: exendin-1: secretin-like.
    
    


Intercellular adhesion molecule

    
    
        (SEQ ID NO: 179)
        Posttranslational lanthionine ring: S18-C23
        Function: anti-hiv.
    
    


Tachyplesin I

    
    
        (S3,S12)-Sequence (SEQ ID NO: 180)
        Posttranslational lanthionine rings S3-C7, S12-C16
        Function Hiv cell fusion inhibitor, anti tumor peptide, antimicrobial peptide.
    
    


HIV (gp120) antigenic peptide fragment

    
    
        (S10,C 14)-Sequence (SEQ ID NO: 181)
        Posttranslational lanthionine ring S10-C14.
    
    


HIV (gp 41) antigenic peptide 1 fragment

    
    
        (S2)-Sequence (SEQ ID NO: 26)
        Posttranslational lanthionine S2-C8.
    
    


HIV (gp41) antigenic peptide 5

    
    
        (S20)-Sequence (SEQ ID NO: 182)
        Posttranslational lanthionine ring S20-C26.
    
    


HIV protease inhibitors

    
    
        (SEQ ID NO: 183)
        Posttranslational lanthionine ring T1-C5
        Function: inhibitor HIV protease.
    
    


Insulin-like growth factor-I analog

    
    
        S1,C4-Sequence (SEQ ID NO: 184)
        Posttranslational lanthionine rings: S1-C4, S11-C12.
    
    


IGF II 69-84:

    
    
        (C7)-Sequence (SEQ ID NO: 185)
        Posttranslational lanthionine ring S3-C7.
    
    


Interleukin-8 fragment:

    
    
        (S6, C10)-Sequence (SEQ ID NO: 186)
        Posttranslational lanthionine ring S6-C 10
        Function: attraction neutrophils, basophils and T-cells, but not monocytes. It is involved in neutrophil activation and is released from several cell-types in response to inflammation.
    
    


Interleukin-2 fragment(60-70) (T-cell growth factor)

    
    
        (SEQ ID NO: 187)
        Posttranslational lanthionine ring S67-C70.
    
    


Leucokinin I (neuroactive peptide)

    
    
        C8-Sequence (SEQ ID NO: 188)
        Posttranslational lanthionine ring: S6-C8.
    
    


Leukopyrokinin

    
    
        C4-Sequence (SEQ ID NO: 189)
        Posttranslational lanthionine ring:T1-C4
        Function: mediates visceral muscle contractile activity.
    
    


Mastoparan

    
    
        S5,C8-Sequence (SEQ ID NO: 190)
        Posttranslational lanthionine ring: S5-C8
        Function: Wasp venom membrane-active toxin.
    
    


Melanin concentrating hormone

    
    
        S11-Sequence (SEQ ID NO: 191)
        Posttranslational lanthionine ring: S11-C16
        Function: possible neurotransmitter, involved in the regulation of goal directed behavior.
    
    


Melittin

    
    
        C14-Sequence (SEQ ID NO: 192)
        Posttranslational lanthionine ring: T10-C14
        Function: Bee venom membrane-active peptide.
    
    


Motilin

    
    
        C9-Sequence (SEQ ID NO: 193)
        Posttranslational lanthionine ring: T6-C9
        Function: regulation of interdigestive gastrointestinal motility.
    
    


Neuropeptide Y

    
    
        C26-Sequence (SEQ ID NO: 194)
        Posttranslational lanthionine ring S22-C26
        Function:control of feeding and secretion of gonadotropin-release hormone.
    
    


Osteocalcin

    
    
        S4,C8-Sequence (SEQ ID NO: 195)
        Posttranslational lanthionine ring: S4-C8
        Function: constitutes 1-2% of the total bone protein, it binds strongly to apatite and calcium.
    
    


(N-acetyl-)beta-endorphin 1-27

    
    
        (C21)-Sequence (SEQ ID NO: 196)
        Posttranslational methyllanthionine T16-C21
        Functions: analgesia, behavioral changes, growth hormone release.
    
    


Ras oncogene related peptide

    
    
        HU-rasha 
        (S2, C5)-Sequence (SEQ ID NO: 197)
        Posttranslational lanthionine ring S2-C5.
    
    


Ras oncogene related peptide

    
    
        Hu-rasT24 
        (S2, C5)-Sequence (SEQ ID NO: 198)
        Posttranslational lanthionine ring S2-C5.
    
    


Ras oncogene-related peptide

    
    
        Hu-(Hu-rast24)-Lys
        (S3, C6)-Sequence (SEQ ID NO: 199)
        Posttranslational lanthionine ring S3-C6.
    
    









TABLE 1B





Albumin







Accession number: P02768


(SEQ ID NO: 200)









    
    
        Disulfide bonds: 77-86;99-115; 114-125; 148-193; 192-201;224-270;269-277;289-303;302-313;340-385;384-393;416-462;461-472;485-501;500-511;538-583;582-591 (numbers correspond to the precursor protein which contains 24 amino acids more, N-terminally)
        Function: regulation colloidal osmotic pressure of the blood plasma, binding blood plasma molecules.
    
    


Alglucerase

    
    
        Accession number: P04062
        (SEQ ID NO: 201)
        Function: glucosylceramidase.
    
    


Alpha-galactosidase

    
    
        Accession number: P06280
        (SEQ ID NO: 202)
        Function: galactosidase.
    
    


Alteplase

    
    
        Accession number: P00750
        (SEQ ID NO: 203)
        Disulfide: 41-71; 69-78; 86-97; 91-108;110-119; 127-208; 148-190; 179-203; 215-296;236-278; 267-291; 299-430; 342-358; 350-419; 444-519; 476-492;509-537 (counted with 35 additional N-terminal aa)
        Function: cleaves plasminogen to form plasmin
    
    


Antithrombin III

    
    
        Accession number: P01008
        (SEQ ID NO: 204)
        Disulfide: 40-160;53-127; 279-462 (counted with 32 aa signal sequence)
        Function: inhibition coagulation.
    
    


Aprotinin

    
    
        Accession number: P00974
        Disulfide: 40-90; 49-73; 65-86 (counting with 35 aa N-terminal)
        Function: Inhibits trypsin, kallikrein, chymotrypsin and plasmin.
    
    


Asparaginase

    
    
        Accession number: P20933
        Sequence:
        alpha-chain (SEQ ID NO: 206)
        beta-chain (SEQ ID NO: 207)
        Disulfide: 64-69; 163-179; 286-306; 317-345 (counted with 23 extra N-terminal aa)
        Function: Cleaving glycoproteins.
    
    


Becaplermin

    
    
        Accession number: P01127
        (SEQ ID NO: 208)
        Disulfide: 97-141; 130-178; 134-180;124-124 INTERCHAIN; 133-133 INTERCHAIN. (counting with 81 aa N-terminal)
        Function: growth factor from platelet.
    
    


Bone morphogenic protein 7

    
    
        Accession number: P34819
        (SEQ ID NO: 209)
        Function: induces bone formation, involved in Ca regulation.
    
    


Catalase

    
    
        Accession number: P04040
        (SEQ ID NO: 210)
        Function: protection against H2O2. 
    
    


Cecropin B

    
    
        Accession number: P01508
        (SEQ ID NO: 211)
        Function: Antibacterial.
    
    


Cellulase

    
    
        Accession number: P23548
        (SEQ ID NO: 212)
        Function: hydrolysis cellulose.
    
    


Choriogonadotropin alpha

    
    
        Accession number: P01215
        (SEQ ID NO: 213)
        Function: A heterodimer of a common alpha chain and a unique beta chain confers biological specificity to thyrotropin, lutropin, follitropin and gonadotropin.
    
    


Choriogonadotropin beta

    
    
        Accession number: P01233
        (SEQ ID NO: 214)
        Disulfide: 29-77; 43-92; 46-130; 54-108; 58-110; 113-120
        Function: stimulates steroid production.
    
    


Chymopapain

    
    
        Accession number: P14080
        (SEQ ID NO: 215)
        Disulfide: 156-197; 190-229; 287-338 (counting with 134 aa N-terminal)
        Function: Thiol protease.
    
    


Chymotrypsin

    
    
        Accession number: P54414
        (SEQ ID NO: 216
        Function: serine protease.
    
    


Big Endothelin

    
    
        (SEQ ID NO: 217)
        Function: endothelins are endothelium derived vasoconstrictor peptides.
    
    


Clostridium botulinum toxin type A

    
    
        Accession number: Q45894
        Sequence A-light chain (SEQ ID NO: 218)
        Sequence A-heavy chain (SEQ ID NO: 219)
        Disulfide: 429-453 INTERCHAIN (BY SIMILARITY); 1234-1279
        Function: blocking neurotransmitter release by hydrolysis of snap25.
    
    


Clostridium botulinum toxin type B

    
    
        Accession number: P10844
        (SEQ ID NO: 220)
        Disulfide: 436-445 INTERCHAIN (PROBABLE).
        Function: endopeptidase that cleaves synaptobrevin-2 and thus blocks neurotransmission.
    
    


Collagen

    
    
        Accession number: P30754
        (SEQ ID NO: 221)
        Function: fibril formation
    
    


Collagenase

    
    
        Accession number: P08897
        (SEQ ID NO: 222)
        Disulfide: 60-76; 181-196; 206-234
        Function: Serine protease.
    
    


Corticotropin, ACTH

    
    
        Accession number: P01189
        (SEQ ID NO: 223)
        Disulfide: 28-50 (counting with 26 aa signal)
        Function: melanocyte stimulation.
    
    


Dornase alfa

    
    
        Accession number: P24855
        (SEQ ID NO: 224)
        Disulfide: 123-126; 195-231 (counted with 21 aa extra N-terminal)
        Function: endonucleolytic, binds G-actin.
    
    


Eptacog alpha (factor VII)

    
    
        Accession number: P08709
        (SEQ ID NO: 225)
        Disulfide: 77-82; 110-121; 115-130; 132-141; 151-162; 158-172; 174-187; 195-322; 219-224; 238-254; 370-389; 400-428 (counted with 61 aa N-terminally)
        Function: coagulation.
    
    


Etanercept

    
    
        Accession number: P20333
        (SEQ ID NO: 226)
        Disulfide: 40-53; 54-67; 57-75; 78-93; 96-110; 100-118; 120-126; 134-143; 137-161; 164 179 (counted with 22 aa extra N-terminally)
        Function: receptor TNF-alpha.
    
    


Erythropoietin

    
    
        Accession number: P01588
        (SEQ ID NO: 227)
        Disulfide: 34-188; disulfide: 56-60 (counted with 27 aa N-terminally)
        Function: erythropoiese.
    
    


Exendin-4

    
    
        Accession number: P26349
        (SEQ ID NO: 228)
        86 AMIDATION (G-87 PROVIDE AMIDE GROUP). (counted with 23 aa signal N-terminally)
        Function: secretin-like.
    
    


Factor VIII

    
    
        Accession number: P00451
        (SEQ ID NO: 229)
        Disulfide: 172-198;547-573; 1851-1877; 2040-2188; 2193-2345 (counted with 19 aa extra N-terminally)
        Function: coagulation.
    
    


Factor IX

    
    
        Accession number: P00740
        Sequence:
        Light chain: (SEQ ID NO: 230)
        Heavy chain: (SEQ ID NO: 231)
        Disulfide: 64-69; 97-108; 102-117; 119-128; 134-145; 141-155; 157-170 (counted in the precursor)
        Function: coagulation.
    
    


Factor X

    
    
        Accession number: P00742
        Sequence:
        Light chain: (SEQ ID NO: 232)
        Heavy chain: (SEQ ID NO: 223)
        Disulfide: 90-101; 95-110; 112-121; 129-140; 136-149; 151-164; 172-342; 241-246; 261 277; 390-404; 415-443 (counted with 40 aa signal sequence)
        Function: coagulation, factor Xa (part of factor X-heavy chain) is a vitamin K-dependent glycoprotein that converts prothrombin into thrombin in the presence of amongst others anionic phospholipid.
    
    


Factor XIII

    
    
        Accession number: P00488
        (SEQ ID NO: 234)
        Function: coagulation, indirectly stabilizing fibrin chains.
    
    


Fibronectin

    
    
        Accession number: P02751
        (SEQ ID NO: 235)
        Disulfide: 52-78; 76-87; 97-125; 123-135; 141-169; 167-179; 186-215; 213-225; 231-260; 258-308-335; 333-342; 360-386; 374-401; 420-446; 434-461; 470-498; 496-508; 518 545; 543-555; 561-589; 587-599; 2206-2235; 2233-2245; 2251-2278; 2276-2288; 2295-2319; 2317-2333; 2367—2367; 2371—2371 INTERCHAIN (WITH 2367 OF OTHER CHAIN). (counted with 31 aa extra N-terminally)
        Function: wound healing, cell shape.
    
    


Fibrinogen

    
    
        Accession number: P02671
        (SEQ ID NO: 236)
        Disulfide: 47—47 INTERCHAIN (WITH C-47′); 55—55 INTERCHAIN (WITH C-95 IN BETA); 64—64 INTERCHAIN (WITH C-49 IN GAMMA); 68—68 INTERCHAIN (WITH C-106 IN BETA); 180—180 INTERCHAIN (WITH C-165 IN GAMMA); 184—184 INTERCHAIN (WITH C-223 IN BETA); 461-491
        Function: fibrin formation, platelet aggregation.
    
    


Filgrastim

    
    
        Accession number: P09919
        (SEQ ID NO: 237)
        Disulfide: 69-75; 97-107 (counted with 30 aa N-terminally)
        Function: granulocyte stimulation.
    
    


Follitropin alpha

    
    
        Accession number: P37036
        (SEQ ID NO: 238)
        Disulfde: 11-35; 14-64; 32-86; 36-88; 63-91
        Function: follicle stimulation.
    
    


Follitropin beta

    
    
        Accession numbers: P01225
        (SEQ ID NO: 239)
        Disulfide: 21-69; 35-84; 38-122; 46-100; 50-102; 105-112 (counted with 18 aa N-terminally)
        Function: follicle stimulation.
    
    


Growth hormone releasing hormone

    
    
        Accession number: P48144
        (SEQ ID NO: 240)
        Function: growth hormone release.
    
    


Pituitary adenylate cyclase activating polypeptide

    
    
        Accession number: P48144
        (SEQ ID NO: 241)
        Function: see name.
    
    


Hyaluronidase

    
    
        Accession number: P38567
        (SEQ ID NO: 242)
        Function: glycosyl hydrolase.
    
    


Hirudin II

    
    
        Accession number: P28504
        (SEQ ID NO: 243)
        Disulfide: 6-14; 16-28; 22-39
        Function: thrombin inhibitor.
    
    


Imiglucerase

    
    
        Accession number: P04062
        (SEQ ID NO: 244)
        Function: Glucohydrolase.
    
    


Interleukin 2

    
    
        Accession number: P01585
        (SEQ ID NO: 245)
        Disulfide: 78-125 (counted with 20 aa signal N-terminally)
        Function: growth factor.
    
    


Interferon alpha-4

    
    
        Accession numbers: P01562
        (SEQ ID NO: 246)
        Disulfide: 24-122; 52-162 (counted with 23 aa N-terminally)
        Function: Antiviral, interferon stimulates the production of two enzymes, a protein kinase and an oligoadenylate synthetase.
    
    


Interferon-beta

    
    
        Accession numbers: P01575
        (SEQ ID NO: 247)
        Function: antiviral, antibacterial and anticancer.
    
    


Intrinsic factor

    
    
        Accession number: P27352
        (SEQ ID NO: 248)
        Disulfide: 26-246; 103-288; 143-182 (counted with 18 aa N-terminally extra)
        Function: cobalamin endocytosis.
    
    


Invertase

    
    
        Accession number: Q60115
        (SEQ ID NO: 249)
        Function: sucrase.
    
    


Lepirudin

    
    
        Accession number: P01050
        (SEQ ID NO: 250)
        Disulfides: 6-14; 16-28
        Function: thrombin inhibitor.
    
    


Lutropin beta

    
    
        Accession number: P01229
        (SEQ ID NO: 251)
        Disulfide: 29-77; 43-92; 46-130; 54-108; 58-110; 113-120
        Function: stimulates synthesis of steroids.
    
    


Lysozyme

    
    
        Accession number: P21270
        (SEQ ID NO: 252)
        Function: hydrolysis peptidoglycan.
    
    


Metalloproteinase inhibitor

    
    
        Accession number: P16035
        Accession number: P21270
        (SEQ ID NO: 253)
        Disulfides: 27-98; 29-127; 39-152; 154-201; 159-164; 172-193 (counted with 26 aa N-terminally)
        Function: inactivation protease.
    
    


Neurophysin

    
    
        Accession number: P01185
        (SEQ ID NO: 254)
        Disulfide: 41-85; 44-58; 52-75; 59-65; 92-104; 98-116; 105-110
        Function: Neurophysin binds vasopressin.
    
    


Papain

    
    
        Accession number: P00784
        (SEQ ID NO: 255)
        Disulfide: 155-196; 189-228; 286-333 (counted with 18 aa N-terminally)
        Function: Proteinase.
    
    


Pepsin

    
    
        Accession number: P00790
        (SEQ ID NO: 256)
        Disulfide: 107-112; 268-272; 311-344 (counted with 62 aa N-terminally)
        Function: Peptidase.
    
    


Plasminogen

    
    
        Accession number: P00747
        (SEQ ID NO: 257)
        Disulfide: 49-73; 53-61; 103-181; 124-164; 152-176; 185-262; 188-316; 206-245; 234-257; 275-352; 296-335; 324-347; 377-454; 398-437; 426-449; 481-560; 502-543; 531-555; 567-685; 577-585; 607-623; 699-766; 729-745; 756-784
        Function: Protease.
    
    


Protamine

    
    
        Accession number: P04554
        (SEQ ID NO: 258)
        Function: histon substitution.
    
    


Prothrombin

    
    
        Accession number: P12259
        (SEQ ID NO: 259)
        Disulfide: 167-193; 500-526; 1725-1751; 1907-2061; 2066-2221 (counted with 28 N-terminal aa)
        Function: Coagulation.
    
    


Protirelin

    
    
        Accession number: P20396
        (SEQ ID NO: 260)
        Function: thyrotropin release.
    
    


SC3

    
    
        Accession number: P16933
        (SEQ ID NO: 261)
        Function: hydrophobin.
    
    


Sermorelin

    
    
        Accession number: P01286
        (SEQ ID NO: 262)
        Function: growth hormone release.
    
    


Streptodornase

    
    
        Accession number: P26295
        (SEQ ID NO: 263)
        Function: DNAse.
    
    


Streptokinase

    
    
        Accession number: P00779
        (SEQ ID NO: 264)
        Function: activating plasminogen.
    
    


Thyroglobulin

    
    
        Accession number: P01266
        (SEQ ID NO: 265)
        Function: precursor thyroid hormone.
    
    


Urokinase

    
    
        accession: P00749
        (SEQ ID NO: 266)
        Function: plasminogen activation.
    
    









TABLE 2





Leader Peptides:


















Epicidin-280
(SEQ ID NO: 267)



Pep-5
(SEQ ID NO: 268)



Epilancin-K7
(SEQ ID NO: 269)



Nisin-A/Z
(SEQ ID NO: 270)



Subtilin
(SEQ ID NO: 271)



Epidermin
(SEQ ID NO: 272)



Gallidermin
(SEQ ID NO: 273)



Mutacin-1140/III
(SEQ ID NO: 274)



Lacticin-481
(SEQ ID NO: 275)



Variacin
(SEQ ID NO: 276)



Mutacin-II
(SEQ ID NO: 277)



Streptococcin-A-FF22
(SEQ ID NO: 278)



Salivaricin-A
(SEQ ID NO: 279)



Sublancin
(SEQ ID NO: 280)



Lactocin-S
(SEQ ID NO: 281)



Ruminococcin A
(SEQ ID NO: 282)



Butyrivibriocin OR79A
(SEQ ID NO: 283)



Streptococcin A-M49
(SEQ ID NO: 284)



Bacteriocin J46
(SEQ ID NO: 285)



Salivaricin A1
(SEQ ID NO: 286)



Streptin
(SEQ ID NO: 287)



Plantaricin-W alpha
(SEQ ID NO: 288)



Lacticin-3147A1
(SEQ ID NO: 289)



Staphylococcin-C55 alpha
(SEQ ID NO: 290)



Plantaricin-W beta
(SEQ ID NO: 291)



Lacticin-3147A2
(SEQ ID NO: 292)



Staphylococcin-C55 beta
(SEQ ID NO: 293)



Cytolysin-LL
(SEQ ID NO: 294)



Cytolysin-LS
(SEQ ID NO: 295)



Cinnamycin
(SEQ ID NO: 296)



Mersacidin
(SEQ ID NO: 297)

## Claims

1. A method for producing a thioether bridge containing polypeptide of a non-Gram positive bacterium origin in a host cell, said method comprising: selecting a host cell having a nucleic acid molecule comprising:
a first nucleic acid fragment encoding a leader peptide; 
a second nucleic acid fragment encoding a polypeptide comprising a sequence selected from the group of sequences consisting of Ser-Cys, Ser-Xaa1-20-Cys (SEQ ID NO: 310), Thr-Cys, and Thr-Xaa1-20-Cys (SEQ ID NO: 311), wherein Xaa is any amino acid and the polypeptide is of the non-Gram positive bacterium origin; 
wherein the first and second nucleic acid fragments are within the same open reading frame as the nucleic acid molecule; and 
wherein the leader peptide acts as a translocation signal sequence and a recognition signal such that the thioether bridge formation may occur; 
selecting the host cell for the presence of the transporter protein LanT or a functional equivalent thereof having LanT activity; 
translating the nucleic acid molecule, thus producing the leader peptide and the polypeptide comprising the sequence selected from the group of sequences consisting of Ser-Cys, Ser-Xaa1-20-Cys (SEQ ID NO: 310), Thr-Cys, and Thr-Xaa1-20-Cys (SEQ ID NO: 311); and 
harvesting the polypeptide containing the thioether bridge from a medium of the host cell.

2. The method according to claim 1, further comprising harvesting the polypeptide containing the thioether bridge after the leader peptide is detected in the medium of the host cell.

3. The method according to claim 1, wherein the leader peptide is selected from the group consisting of the leader peptides of Table 2.

4. The method according to claim 1, wherein the host cell is of a Gram-negative or eukaryotic origin.

5. The method according to claim 1, wherein the polypeptide containing the thioether bridge has not undergone intra-cellular post-translational modification.

6. The method according to claim 1, wherein the host cell is not provided with a LanB protein or a functional equivalent thereof having LanB activity.

7. The method according to claim 1, wherein the host cell is not provided with a LanC protein or a functional equivalent thereof having LanC activity.

8. The method according to claim 6, wherein the host cell is of Gram-negative or eukaryotic origin.

9. The method according to claim 7, wherein the host cell is of Gram-negative or eukaryotic origin.

10. The method according to claim 5, wherein the intra-cellular post-translational modification comprises dehydration of a serine, dehydration of a threonine or thioether bridge formation.

11. The method according to claim 1, wherein the polypeptide comprises the sequence Ser-Xaa2-15-Cys (SEQ ID NO: 312) or Thr- Xaa2-15-Cys (SEQ ID NO: 313).

12. A method for producing a thioether bridge containing polypeptide of a non-Gram positive bacterium origin, said method comprising: providing a host cell having a nucleic acid molecule, the nucleic acid molecule comprising:
a first nucleic acid fragment encoding a leader peptide of a nisin peptide origin; 
a second nucleic acid fragment encoding a pre-polypeptide comprising a sequence selected from the group of sequences consisting of Ser-Cys, Ser-Xaa1-20-Cys (SEQ ID NO: 310), Thr-Cys, and Thr-Xaa1-20-Cys (SEQ ID NO: 311), wherein Xaa is any amino acid and the pre-polypeptide is of the non-Gram positive bacterium origin; 
wherein the first and second nucleic acid fragments are within the same open reading frame as the nucleic acid molecule; 
translating the nucleic acid molecule, thus expressing the leader peptide and the pre-polypeptide; and 
harvesting the thioether bridge containing polypeptide from a medium of the host cell.

13. The method according to claim 12, wherein the pre-polypeptide comprises the sequence Ser-Xaa2-15-Cys (SEQ ID NO: 312) or Thr- Xaa2-15-Cys (SEQ ID NO: 313).