bluuebunny/crossref_metadata_2025 huggingface dataset:
4-(2′-Carboxyphenyl)-4-oxobutyryl Coenzyme A Ester, an Intermediate in Vitamin K2 (Menaquinone) Biosynthesis
Authors: Kolkmann Rainer , Leistner Eckhard
Published: August 2018

Enzyme preparations from Mycobacterium phlei, Escherichia coli and Galium mollugo cell suspension cultures were incubated in the presence of 4-(2′-carboxyphenyl)-4-oxobutyrate (i.e. o- succinylbenzoic acid. OSB. 1). ATP. coenzyme A and Mg2+. The main product isolated from the incubation mixture was 4-(2′-carboxyphenyl)-4-oxobutyryl coenzyme A ester (2) as determined by comparison with synthetic coenzyme A esters. Synthetic and enzymically formed 4-(2′-car-boxyphenyl)-4-oxobutyryl coenzyme A ester (2) was shown to be enzymically converted to an intermediate in vitamin K2 biosynthesis viz. 1.4-dihydroxy-2′-naphthoic acid (5). The enzymic formation of 2-(3′-Carboxypropionyl)benzoyl coenzyme A ester (3) and 4-(2′-carboxyphenyl)-4-oxobutyryl-di-coenzyme A ester (4) was also observed. They appeared in minor amounts, how­ever. These esters were not convertible to 1.4-dihydroxy-2-naphthoic acid (5).
Role of Pyrophosphate: Fructose-6-phosphate 1-Phosphotransferase in Glycolysis in Cultured Catharanthus roseus Cells
Authors: Ashihara Hiroshi , Horikosi Tiharu
Published: August 2018

The maximum catalytic activity of pyrophosphate: fructosc-6-phosphate 1-phosphotransferase (PPi-PFK) was approximately three fold greater than that of ATP: fructosc-6-phosphate 1-phosphotransferase (ATP-PFK) in Catharanthus roseus cells at any stage of culture. The levels of both enzymes increased after subculture of the cells, reached their maximum levels on day 3-4, and then decreased. PPi-PFK partially purified from Catharanthus roseus required fructose-2,6-bis- phosphate (F2,6BP) for its activity. The Ka value of the enzyme for F2,6BP was 26 nᴍ. The Km values for fructose-6-phosphate (F6P) and sodium pyrophosphate (PPi), at physiological pH (7.2) in the presence of 1 µᴍ F2,6BP, were 0.59 mᴍ and 48 µᴍ, respectively. Intracellular levels of PPi and F6P varied from 17-71 nmol and from 37-65 nm per g fresh weight of the cells during culture. These results suggest that PPi-PFK is functional in Catharanthus roseus cells in vivo. The role of PPi-PFK in carbohydrate metabolism in heterotrophic, cultured plant cells is discussed.
Isolation and Characterization of a Supramolecular Complex of Subunit III of the ATP-Synthase from Chloroplasts
Authors: Fromme Petra , Boekema Egbert J. , Gräber Peter
Published: August 2018

In SDS gels of purified, highly active ATP-synthase from chloroplasts, CF0F1 a protein band was detected at an apparent molecular weight of 100 kDa. This protein was isolated on a prepara­tive SDS gel. The 100 kDa protein can be dissociated at increased temperature or increased incubation time into an 8 kDa protein, which is identical with the subunit III of CF0 (DCCD- binding protein or proteolipid). This implies that the 100 kDa band is a stable supramolccular complex containing at least 12 copies of subunit III. Electron micrographs reveal a diameter of 6.3 nm and a membrane spanning length of 6.1 nm. We assume that this supramolecular complex represents a stable native substructure of CF0F1.
The Polyphasic Rise of Chlorophyll Fluorescence upon Onset of Strong Continuous Illumination: II. Partial Control by the Photosystem II Donor Side and Possible Ways of Interpretation
Authors: Schreiber Ulrich , Neubauer Christian
Published: August 2018

The fluorescence rise kinetics in saturating light display two well separated components with largely different properties. The rapid rise from F0 to a first intermediate level, I1 is photochemically controlled, while the following phases leading to a secondary intermediate level, I2 and to a peak level, P, are limited by thermal reactions. Treatments which primarily affect components at the photosystem II donor side are shown to increase quenching at I1 and/or to suppress the secondary fluorescence rise to I2. Preillumination by single turnover saturating flashes causes I1- quenching oscillating with period-4 in dependence of flash number. It is suggested that this quenching correlates with (S2 + S3) states of the watersplitting enzyme system. Suppression of the secondary, I1 - I2 rise component is invariably found with treatments which lower electron donation rate by the watersplitting system and are known to favor the low potential form of cyt b 559.

Three different mechanisms are discussed on the basis of which donor-side dependent quench­ing could be interpreted: 1) Non-photochemical quenching by accumulation of the P 680+ radical cation. 2) Dissipative photochemical quenching at a special population of PS II centers (β- or non- B centers) displaying low donor capacity and high rates of charge recombination. 3) Dissipative photochemical quenching via cyclic electron flow around PS II, involving alternate donors to P 680+ (like cyt b 559 or carotenoid in their low potential forms), which can compete when donation rate from the water splitting system is slowed down. The possibility of donor-side limitation also being involved in “energy dependent” quenching is discussed.
Active Cyanogenesis — in Zygaenids and Other Lepidoptera
Authors: Witthohn K. , Naumann C. M.
Published: August 2018

The liberation of hydrocyanic acid by intact not damaged living insects is described as “active cyanogenesis”. This phenomenon - as in contrast to “passive cyanogenesis” observed in plants, where enzyme and substrate get in contact only after tissue damage - is reported from the Zygaenidae. Quantitative data demonstrate that the Zygaenidae can increase the amount of emitted HCN upon irritation. The significance of this phenomenon as a mean of defense is discussed.
MHC-Antigens: Constituents of the Envelopes of Human and Simian Immunodeficiency
Authors: Gelderblom Hans , Reupke Hilmar , Winkel Thorsten , Kunze Rudolf , Pauli Georg
Published: August 2018

Immunoelectron microscopy was applied to study the antigenic make-up of human and simian immunodeficiency viruses (HIV, SIV) grown in cells expressing either MHC class I (Molt-3) or MHC class I and II (H9) antigens. A variety of antibodies directed against the surface glycopro­ tein gpl20 of HIV and against MHC class I and II antigens were employed. Consistent with earlier observations on the loss of HIV envelope components, gp120 was only weakly demonstra­ ble on the mature virion.

MHC class I determinants were present regularly in small amounts on HIV and SIV. Class II antigens, e.g. HLA-DR were found in high density on HIV and SIV grown in H9 cells, but were absent, as expected, on virus grown in Molt-3 cells. These cellular surface antigens are con­ stituents of the virion.

The presence of MHC class II antigens in virus preparations used for diagnostic purposes might explain some of the false positive results in HIV serology. Possible biological implications of these virus associated cellular antigens for the pathogenicity of HIV are discussed.
Notes: (Z)-3-Tetradecenyl Acetate as a Sex-Attractant Component in Gelechiinae and Anomologinae (Lepidoptera: Gelechiidae)
Authors: Priesner Ernst
Published: August 2018

The title compound, unreported as an insect pheromone component, effectively attracted certain male Gelechiidae (genera Chionodes, Monochroa, Argolamprotes) as a sin­gle chemical. Trap captures with this chemical decreased on addition of either (E)-3-dodecenyl acetate. (E)-3-tetra- decenyl acetate or (Z)-3-tetradecen-1-ol. the sexual attractants of other, closely related species. Results on an Aproaerema test species showing a synergistic attraction response to combinations of (Z)-3-tetradecenyl acetate with its homologue (Z)-3-dodecenyl acetate are included.
Quantitative Histochemical Analysis of Starch, Malate and K+, together with the Activity of Phospho-enolpyruvate Carboxylase along an Elongating Primary Leaf of Hordeum vulgare
Authors: Hampp R. , Outlaw W. H. , Ziegler H.
Published: August 2018

The content of starch, malate, potassium and the activity of phospho-enolpyruvate carboxylase (PEPC) were analyzed by quantitative histochemistry in mesophyll cells of different zones along the axis of lyophylized primary elongating leaves of barley. The concentrations of potassium and malate were low in the region of the intercalary meristem (close to the point of grain attachment), but concentrations of solutes increased abruptly and stoichiometrically (equivalent basis) in the elongation zone (2 to 10 mm from the leaf base), where they contributed approximately -0.17 megapascal to the solute potential. Although this solute concentration represents only a minor portion of the reported solute potential, the specific nature of the change, its correlation with a decrease of starch content, and the distribution of the activity of PEPC indicate cell expansion in barley could be augmented by a potassium malate osmoregulatory system that utilizes starch as a source of carbon skeletons.
Biotransformation of Citral by Botrytis cinerea
Authors: Brunerie Pascal , Benda Irmgard , Bock Gudrun , Schreier Peter
Published: August 2018

Biotransformation of citral (1) was studied with four strains of Botrytis cinerea using grape must (A), a synthetic medium (B) and mixtures of A and B. Whereas in A complete metabolization of 1 without evidence of any volatile product was observed, in B nerol (2) and geraniol (3) were found as predominant volatile bioconversion products; in minor amounts (E,Z)-2,6-dimethylocta- 2,6-dien-1,8-diol (4) and (E,E)-2,6-dimethylocta-2,6-dien-1,8-diol (5). 2-methyl-2-hepten-6-one (6), 2-methyl-2-hepten-6-ol (7), 2-methyl-2-hepten-6-one-1-ol (8) and 2-methyl-y-butyrolactone (9) were identified. Using small amounts of A in B (1:700 to 5:700) low yields of 2 and 3 were obtained, whereas the quantities of 4, 5. 6 and 8 increased. Quantitatively, the results were strongly dependent on the strains used. The bioconversion products were all identified by capil­lary gas chromatography (HRGC) and coupled HRGC techniques, i.e. -mass spectrometry (HRGC-MS) and -Fourier transform infrared spectroscopy (HRGC-FTIR).
Amperometric Titration Largely Overestimates Chloride Concentrations in Chloroplast Extracts
Authors: Schröppel-Meier G. , Kaiser W. M
Published: August 2018

Determination of chloride contents in aqueously isolated chloroplasts from spinach by amperometric titration indicated chloride concentrations of 60 to 100 mmol 1-1 (based on a chloroplast volume of 25 μl mg-1 chlorophyll). However, when analyzed by anion chromatography, chloride contents in chloroplasts were much lower (1-8 mmol 1-1).

In leaf extracts chloride concentrations obtained with both methods were rather similar. Boiling of chloroplast extracts prior to chloride titration reduced indicated chloride contents by a factor of three or four, but did not change results obtained with anion chromatography. It is concluded that chloroplasts contain large amounts of silver complexing agents giving rise to a drastic overestima­tion of chloroplast chloride concentrations when measured by amperometric titration. Boiling and centrifugation of extracts apparently precipitates these compounds only insufficiently.
Distinct Substrate Specificity of Dihydroflavonol 4-Reductase from Flowers of Petunia hybrida
Authors: Forkmann G. , Ruhnau B.
Published: August 2018

Dihydroflavonol 4-reductase from Petunia flowers cata­lyzes the reduction of dihydroquercetin to leucocyanidin and, in particular, of dihydromyricetin to leucodelphinidin, whereas reduction of the simple dihydroflavonol dihydro- kaempferol to leucopelargonidin could not be observed. This special substrate specificity of dihydroflavonol 4-re­ductase is most probably the reason for the observations that delphinidin derivatives are the main end products of anthocyanin biosynthesis in Petunia flowers, whereas an- thocyanins based on pelargonidin are rarely found and, if present, are only formed in very small amounts.
Degree of saturation of blood plasma in vertebrates with octocalcium phosphate
Authors: Driessens F. C. M. , Verbeeck R. M. H. , Dijk J. W. E. van , Borggreven J. M. P. M.
Published: August 2018

In previous papers it has been shown that octocalcium phospate OCP occurs in bone mineral of vertebrates. Although this compound is not stable, there is a continuous new-formation of OCP due to bone turnover. Literature data of the calcium and phosphate concentrations in the blood plasma of vertebrates were collected and the degree of saturation with OCP was calculated. The results show that blood plasma of vertebrates is almost saturated with OCP. This fact indicates that OCP is the solubility controlling phase in the mineral of vertebrates. Further it verifies the expectation based on physicochemical theory that the interaction between body fluids and bone mineral is important in the calcium and phosphate homeostasis
Conformational studies of biliproteins from the insects pieris brassicae and cerura vinula
Authors: Scheer Hugo , Kayser Hartmut
Published: August 2018

Chromophore conformation and protein secondary structure of biliproteins from the butterfly, Pieris brassicae, and the moth, Cerura vinula, have been investigated by absorption, circular dichroism and fluorescence spectroscopy. The chromophore of the P. brassicae protein, biliverdin IXy, has probably a cyclic-helical structure similar to that of free bile pigments of the biliverdin type. Though achiral by structure the chromophore displays strong optical activity in the native protein-bound state, but becomes inactive after urea denaturation of the protein. A minor biliprotein from P. brassicae shows absorption, circular dichroism and fluorescence spectra identical to the main biliprotein. In the biliprotein from Cerura vinula the structure of the pigment is still unknown. It has a semi-open conformation intermediate between that of the Pieris proteins and that of the phycobiliprotein, C-phycocyanin, and it retains optical activity after urea denaturation. The band widths and the size of the Stokes shifts of the fluorescence spectra indicate a high degree of conformational flexibility of the chromophores in the two Pieris pigments, and a decreased flexibility in the one from Cerura. In the biliproteins from both insects the polypeptides are low in a-helix content compared to that of phycobiliproteins. From these and earlier data, insect and algal biliproteins seem to be related only distantly if at all, but there exist also considerable differences among insect biliproteins from different species
Triterpenoids in Epicuticular Waxes of Three European Euphorbia Species
Authors: Hemmers Herbert , Gülz Paul-Gerhard , Marner Franz-Josef
Published: August 2018

The epicuticular leaf waxes from E. characias, E. nicaeensis and E. peplus were found to contain pentacyclic triterpenoids in great amounts in addition to the common lipid wax constituents: alkanes, wax esters, aldehydes, primary alcohols and fatty acids. The gross amount of triterpenoids were triterpenols, however, their acetates and fatty acid esters as well as the corresponding ketones were found, too. Distinctive variations in the occurrence of 13 triterpenoids α- and β-amyrin, lupeol, germanicol, α-fernenol, simiarenol, β-amyrinone, lupenone, lupeol acetate, lupeol esters, α- and β-amyrin esters and α-fernenol esters were observed. Therefore all Euphorbia species showed very species specific compositions concerning these triterpenoids.
The Odor-Bouquet of Ips schmutzenhoferi Holzschuh (Col.: Scol.)
Authors: Francke W. , Bartels J. , Schmutzenhofer H. , Kohnle U. , Vité J. P.
Published: August 2018

Ipsenol, Ipsdienol, and E-myrcenol are male specific compounds of Ips schmutzenhoferi. Overall 46 compounds could be identified from males and females. The diversity of oxygenated terpenes is particularly high in males.
(Z)-3- and (Z)-5-Decenyl Acetates, Sex-Attractant Components for Male Eustrotia uncula Cl. (Lepidoptera: Noctuidae)
Authors: Priesner Ernst
Published: August 2018

Male E. uncula showed a synergistic response to lures containing Z3-10:Ac and Z5-10:Ac in a Z3/Z5 ratio of 1/10. The dodecenyl compounds Z5-12:Ac, Z7-12:Ac and Z7-12:OH, perceived via further types of antennal receptor cells, acted inhibitorily on this binary lure. Two species of Euxoa also responded to Z3-10: Ac as a single compound or lure component, respectively. This is the first report of a Δ3-alkenyl compound being involved in sexual attraction in the Noctuidae.
Elektronen-Energie-Verlust-Spektroskopische Untersuchungen an Luftfiltern zur Bewertung der Luftqualität / Electron-Energy-Loss-Spectroscopical Investigations on Air Filters for the Analysis of the Air Quality
Authors: Wolf Bernhard
Published: August 2018

In trace analysis it is more and more attempted to replace wet-chemical detection procedures by methods which allow a quantitative analysis without any material disintegration, but on exploiting the characteristic physical properties of the components searched for. Based on a procedure for physical and biological valuation of the air quality by means of X-ray microanalysis (WDX/EDX), a procedure which was previously developed by our group, we deepened our investigations by the help of electron-energy-loss-spectroscopy (EELS). The combination of that procedure with EELS proved to be very advantageous as it revealed a high sensitivity as well as a high energy resolution. The main advantages are to be found in the simple arrangement of the sample detector and in the fact, not only being able to examine deposits microscopically, but also to analyze them chemically without disintegrating the material. Thus loss of material and denaturation are largely excluded.
Lentinellic Acid, a Biologically Active Protoilludane Derivative from Lentinellus Species (Basidiomycetes) [1]
Authors: Stärk A. , Anke T. , Mocek U. , Steglich W. , Kirfel A. , Will G.
Published: August 2018

A new antimicrobial and cytotoxic sesquiterpenoid, lentinellic acid (1), has been isolated from submerged cultures of Lentinellus ursinus and L. omphalodes. The structure of the antibiotic was elucidated by spectroscopic methods and a single crystal X-ray analysis. 1 may be formed biogenetically by condensation of a protoilludane aldehyde 4 with a malonate unit.
Characterization and Localization of Digitoxin 12 β-Hydroxylase from Cell Cultures of Digitalis lanata EHRH
Authors: Petersen Maike , Seitz Hanns Ulrich , Reinhard Ernst
Published: August 2018

The cytochrome P-450-dependent monooxygenase digitoxin 12β-hydroxylase from cell cultures of Digitalis lanata needs NADPH and molecular oxygen and hydroxylates cardiac glycosides with the aglycon of digitoxigenin to the corresponding derivatives of the C-series. Other electron donors cannot replace NADPH. The apparent Km-values are 26 μᴍ for NADPH, 7.1 μᴍ for β-methyldigitoxin and 10 μᴍ for digitoxin. The reaction is inhibited by NADP+ and cytochrome c in a competitive mode. The optimum temperature was at 20 °C. Low concentrations of Mn2+, Mg2+, and EDTA were slightly stimulatory, but there was no strict dependence on divalent cations. Digitoxin 12β-hydroxylase is very stable at room temperature and the reaction proceeds for more than 20 h. After the addition of 15% glycerol, 70% of the original activity can be retained subsequent to freezing at -18 °C. By means of linear sucrose gradient fractionation of cellular membranes the digitoxin 12β-hydroxylase was found to be located in the endoplasmic reticulum.
Phosphate Binding to Isolated Chloroplast Coupling Factor (CF1)
Authors: Huchzermeyer Bernhard
Published: August 2018

A single binding site for phosphate was found on isolated chloroplast coupling factor in the absence of nucleotides. In our experiments the phosphate binding site showed a Kd of 170 μᴍ. We did not observe any differences whether the ATPase activity of CF] had been activated or not.

If the enzyme was incubated with [γ-32P]ATP the amount of 32P bound per CF1 depended on the pretreatment of the enzyme: In the presence of ADP no ATP or phosphate was bound to CF,. After activation of ATPase activity one mol of ATP per mol CF, was rapidly bound and hydrolyzed while there was a slowly occurring binding of another phosphate without concomitant nucleotide binding.

We conclude that there are two different types of phosphate binding observed in our experiments: 1) Inorganic phosphate can be bound by one catalytic site per mol of CF1 2) The γ-phosphate of ATP is able to bind to an ATP binding domain of the enzyme if this domain can exchange substrates with the incubation medium. This ATP binding domain appears to differ from the site binding inorganic phosphate, because at least a portion of the coupling factor contains more than one labelled phosphate during our ATPase tests.
The Effects of the Herbicide Sethoxydim on Transport Processes in Sensitive and Tolerant Grass Species I. Effects on the Electrical Membrane Potential and Alanine Uptake
Authors: Weber Angela , Fischer Elke , Branitz Helmut Schipp von , Lüttge Ulrich
Published: August 2018

Sethoxydim is a postemergence herbicide used to control grass weeds. Application at concentrations higher than 0.1 mᴍ to leaf segments of the sensitive grass species Poa pratensis and Festuca ovina and the tolerant species Poa annua and Festuca rubra, caused a reduction of the electrical membrane potential (⊿E). The depolarization was reversible and depended linearly on the herbicide concentration. The passive diffusion component of ⊿E was not affected by sethoxydim indicating that the herbicide did not change passive permeability characteristics of the plasmalemma. Consequently sethoxydim reduced the active component of ⊿E that depended on primary active transport processes across the plasmalemma. Moreover, sethoxydim increased the reduction of ⊿E of grass leaf cells that was associated with the onset of H+-amino acid cotransport. Simultaneously the uptake of alanine into leaf segments was reduced. From these results it had to be concluded that the plasmalemma-bound H+-ATPase was inhibited by sethoxydim in sensitive and tolerant grasses. In vitro ATP hydrolysis of plasmalemma vesicles isolated from grass leaves by polymer phase partitioning, however, was not inhibited by sethoxydim. Apparently another primary active transport mechanism that may contribute to an electrochemical H+- gradient across the plasmalemma, i.e. a plasmalemma-bound redox system, should be the site of inhibition responsible for the membrane effects of sethoxydim observed in vivo.
Growth Control and Pattern Regulation in the Lateral Line Systems of Xenopus
Authors: Winklbauer Rudolf
Published: August 2018

In Xenopus, the supraorbital lateral line system consists of a periodic pattern of lateral line organs which is formed by the regular fragmentation of a streak-like primordium. The pattern forming mechanism which subdivides the primordium into individual organs is not capable of adjusting to the variable size of the system. Nevertheless, the number of organs per supraorbital system tends to be held constant. This is achieved by regulating the growth of the system in an appropriate manner.
Studies on the Biosynthesis of Pseudoisoeugenols in Tissue Cultures of Pimpinella anisum
Authors: Martin Rainer , Schilling Gerhard , Reichling Jürgen
Published: August 2018

A leaf-differentiating tissue culture which produced substantial amounts of pseudoisoeugenol- (2-methylbutyrate) has been used to examine the origin of the pseudoisoeugenol skeleton. 14Cand 13C-labelling revealed ʟ-phenylalanine, trans-cinnamic acid and p-coumaric acid as precursors. 13C-labelled precursors proved to be especially useful.
Biosynthesis of Porphyrinogens in Etiolated Euglena gracilis Z. II. Identification of a Regulatory Pteridine
Authors: Juknat A. A. , Dörnemann D. , Senger H.
Published: August 2018

A low molecular weight compound which stimulates the synthesis of porphyrinogens from PBG was isolated and purified from etiolated Euglena gracilis Z. Absorption and fluorescence excitation and emission spectra, as well as the molecular weight, revealed its structure as an unconjugated pteridine.

FTIR bands and 1H NMR signals of the purified compound were identical with those of an authentic sample of 6-biopterin. The structural formula of this compound is given in Fig. 1.
The Role of Cu in Respiration of Pea Plants and Heterotrophically Growing Scenedesmus Cells
Authors: Ayala Matilde Barón , Sandmann Gerhard
Published: August 2018

In Scenedesmus about half of NADH oxidation proceeds via a cyanide-sensitive and the other half via a cyanide-insensitive respiratory pathway. In contrast, respiration is completely cyanide sensitive in pea indicating that the alternative respiratory pathway is absent. Cu deficiency in pea plants and in heterotrophically grown Scenedesmus cells interferes with respiratory activity of mitochondria. In both organisms, the cyanide-sensitive NADH oxidation was strongly decreased during cultivation in low Cu media. Cu sensitivity was also observed for the alternative respiratory pathway in Scenedesmus. These results suggest that a Cu-containing component is involved in the alternative respiratory pathway. This is the main reason why alternative respiration cannot be regarded as a compensation for low cytochrome-oxidase activities during Cu starvation.

The Cu dependency of the cyanide-sensitive respiration was located at the site of cytochrome oxidase. A strong coordination of the biosynthesis of the Cu-containing cytochrome-oxidase complex was evident. When the endogenous Cu pool was low, formation of cytochrome aa3, another component of cytochrome oxidase, was also decreased.
Further Investigations about the Flavin in the L-Amino Acid Oxidase and a Possible Flavin in Photosystem II Complexes from the Cyanobacterium Anacystis nidulans
Authors: Wälzlein Gudrun , Gau Achim E. , Pistorius Elfriede K.
Published: August 2018

The absorption spectrum of the previously purified ʟ-amino acid oxidase from the cyanobacterium Anacystis nidulans has shown considerable variation with each preparation and the spectrum in several preparations was quite different from the absorption spectrum of other simple flavoproteins (E. K. Pistorius and A. E. Gau, Biochim. Biophys. Acta 849, 203, 1986). Here we show that the spectral complexity and variability of the ʟ-amino acid oxidase can be largely explained by the presence of a modified flavin derivative of yet unknown structure besides oxidized FAD and FAD semiquinone. After removal from the enzyme this modified chromophore has absorption maxima at 260, 396 and in the 600 nm region. This derivative of FAD seems to be formed in variable amounts during the purification of the enzyme. On the other hand, extraction of Anacystis photosystem II complexes which contain the flavoprotein, almost exclusively yields modified flavin derivatives and practically no authentic oxidized FAD. The spectrum of the chromophores which have been extracted from photosystem II complexes at different purification stages, is either similar (although not identical) to the spectrum of the chromophore extracted from the isolated ʟ-amino acid oxidase or similar to the spectrum of reduced flavin. All extracted chromophores show a fluorescence emission in the 420 to 560 nm region when excited with light of 390 nm. These results indicate that the flavin present in the ʟ-amino acid oxidase protein as well as in photosystem II complexes from A. nidulans rapidly undergoes modification reactions of yet unknown nature to yield several closely related FAD derivatives. This might possibly be the reason why so far no flavin has been detected in photosystem II. The presence of such modified flavin derivatives in photosystem II complexes of A. nidulans as shown here is an additional support of our hypothesis that an unusual flavin is functional on the donor side of photosystem II.
Thermoluminescence and Delayed Luminescence Characterization of Photosystem IIα and Photosystem IIβ Reaction Centers
Authors: Hideg Éva , Demeter Sándor
Published: August 2018

The thermoluminescence and delayed luminescence characteristics of PS IIα and PS IIβ centers were investigated in BBY particles and stroma thylakoids, respectively. The BBY particles exhibited a thermoluminescence band at 25 °C (B band) which was associated with the charge recombination of the S2Qв
- redox couple and underwent period-2 oscillation in a sequence of flashes. In the flash-induced decay of delayed luminescence of BBY particles a component with a half-time of 34 s corresponded to the B thermoluminescence band and was also assigned to S2Oв
- charge recombination. No corresponding thermoluminescence or delayed luminescence components associated with the secondary acceptor Qв could be observed in the glow curve or delayed luminescence decay of stroma thylakoids. These observations indicate that unlike PS IIα the PS IIβ centers are not associated with the two-electron gate, Qв.
Fluorescence Properties of Hog Kidney Aminoacylase I
Authors: Bruch Thomas vom , Röhm Klaus-Heinrich
Published: August 2018

The state of the tryptophan residues of porcine kidney aminoacylase I (EC 3.5.1.14) was investigated by fluorescence spectroscopy and chemical modification. The pH-dependence of the fluorescence emission spectrum of the enzyme indicates that its native conformation prevails between pH 6 and 9.5. Within this range, the ionization of a residue with an apparent pKa of 7.1 quenches the enzyme fluorescence by about 15%. A similar reduction of fluorescence intensity accompanies the inactivation of aminoacylase I by treatment with N-bromosuccinimide in low excess. This suggests that in both cases a single tryptophyl residue out of eight residues per subunit is affected. Quenching by iodide revealed that, in the native conformation of the enzyme, 5-6 tryptophans per subunit are accessible, while 2-3 are buried within the protein. 8-Anilinonaphthalene- L-sulfonate (ANS) is tightly bound to aminoacylase I (1 mol/mol dimer, Kd < 1 μᴍ). ANS binding does not interfere with substrate turnover; the spectroscopic properties of the aminoacylase- ANS complex are consistent with bound ANS being excited by radiationless energy transfer (RET) from buried tryptophyl residues of the enzyme.
Rebinding of the 33 kDalton Polypeptide of Photosystem II to the D-1/D-2 Sub-Core Complex
Authors: Brody Seymour Steven
Published: August 2018

Specific and stoichiometric binding is shown between the D-1/D-2 sub-core complex and the 33 kDa polypeptide of photosystem II. Fluorescence from chlorophyll is used as an endogenous probe. W h e n binding occurs there is an increase in fluorescence yield, as well as changes in both the fluorescence spectrum and excitation spectrum.
Biosynthesis of Pyrrolidine Alkaloid-Derived Pheromones in the Arctiid Moth, Creatonotos transiens: Stereochemical Conversion of Heliotrine
Authors: Wink M. , Schneider D. , Witte L.
Published: August 2018

In larvae and later developmental stages of Creatonotos transiens, which had been reared on the pyrrolizidine alkaloid 7S-heliotrine, a new major metabolite was detected by capillary GLC. The structure of this metabolite was determined by GLC-MS (EI, CI-MS) and 13C NMR to be 7Rheliotrine and 7R-heliotrine-N-oxide. 7R-Heliotrine is likely to be the direct precursor for the pheromone R( - )-hydroxydanaidal.
A New Method to Prepare Sections from Amphibian Embryos for Immunohistology
Authors: Hausen Peter , Müller Ursula
Published: August 2018

The method involves impregnation of fixed embryos with a solution of plexiglass. The solvent is evaporated slowly. Blocks of plexiglass containing the specimen are thus formed. Sections (1-2 μm) are stretched and attached by an unconvential method. Immunohistological techniques allow antigen localization in a combination of high resolution, excellent quality of the sections and low background.
Biological Information Processing Requires Quantum Logic
Authors: Oi Tetsu
Published: August 2018

Chaos dynamics, which characterizes biological information processing, generates information along the course of temporal development of the relevant system. In this system, the macroscopic uncertainty principle holds between observation time Δt and phase space volume ΔΩ determined by this observation. In other words Δt and ΔΩ cannot simultaneously be small. This principle corresponds to the microscopic uncertainty principle that holds in quantum physics. Through an analogy to this correspondence, it is shown that quantum logic might also govern such macroscopic phenomena as are governed by chaos dynamics.
Studies on Malabsorption in Malnourished Pakistani Children
Authors: Mazahir I. , Rahman M. Ataur , Arif M. A.
Published: August 2018

Malnutrition is a common finding in Pakistan especially in children of low socio-economic class. Impairment of digestion and absorption makes the diet inefficient at fulfilling the requirements of the child and leads to malnutrition. Earlier work from this laboratory has shown that feeding a high-protein diet to children suffering from protein-energy malnutrition (PEM) did not improve their condition. In the present study forty-two malnourished children and seventeen control subjects were investigated. They were divided into five groups, i.e. fibrocystic disease of the pancreas (n = 9), coeliac disease (n = 17), lactose intolerance (n = 5), PEM (n = 5) and nonspecific diarrhoea (n = 6) on the basis of history, clinical impression and biochemical findings. They were from 6 months to 12 years of age. The majority of them were suffering from diarrhoea, distension of the abdomen and retardation of growth. All children were physically examined and anthropometric measurements were recorded. Changes in hair in the form of sparseness, dyspigmentation and easy pluckability were observed in all groups. In PEM, 80% of the cases had enlarged livers. All children had reduced weight and height as compared with the control group. Haemoglobin, total protein and serum albumin showed a decrease and the fall was greatest in PEM cases as compared with the control group.

The excretion of a-amino nitrogen increased in PEM children while hydroxyproline and creatinine levels showed a decrease as compared with the control group. The hydroxyproline index, which signifies the growth rate, was also significantly lower in all groups.

Xylose and lactose tolerance tests were performed after an oral dose of xylose or lactose respectively. The xylose concentration after the test dose was reduced with the lowest values in the coeliac disease group as compared with the control group. In the lactose tolerance test, the patients with lactose intolerance showed lower values as compared with control subjects. Sodium and chloride in sweat showed a significant rise in fibrocystic disease while daily faecal fat excretion was increased in fibrocystic disease, coeliac disease and lactose intolerance cases as compared with the control group. The various biochemical indicies studied indicate that malabsorption played an important role in malnourishment.
The Plasma Membrane ATPase of Dunaliella parva
Authors: Gimmler Hartmut , Schneider Lothar , Kaaden Rosemarie
Published: August 2018

Plasma membrane Mg2+, Ca2+ ATPases were isolated from Dunaliella parva by differential centrifugation and subsequent sucrose gradient centrifugation and analyzed for their properties with special emphasis on ecophysiological requirements of this extremely salt-tolerant alga. Most properties (Vmax- and KM-values, substrate specificity, vanadate and DES sensitivity, resistance against ouabain) indicate that the ATPases of the plasma membrane of D. parva are basically of the same type as that found in the plasma membrane of other algae or higher plants. However, some interesting deviations from the normal characteristics of plasma membrane ATPases of plants were observed for the Dunaliella ATPases. These modifications partially may reflect adaptations of the ATPase and/or the microenvironment of the ATPase to the highly saline environment of this alga; 1) The plasma membrane ATPase of D. parva requires unusually high concentrations of divalent cations (up to 100 mM Mg2+ or Ca2+) for maximal activity. Both cations can substitute for each other. 2) The plasma membrane ATPase of D. parva is extremely resistant against salt. It was stimulated by NaCl or KC1 at concentrations up to 800 mM , whereas at higher salt concentrations the enzyme was inhibited. However, about 2.5 M NaCl was required for halfmaximal inhibition of ATPase activity. 3) The ATPase was inhibited by inhibitors of anion transport such as SITS and D ID S . which suggests direct or indirect involvement of ATPase in anion transport. The possible functions of the plasma membrane ATPases are discussed with special emphasis on problems related to the hypersaline environment of this alga.
Localization and Orientation of Subunit Delta of Spinach Chloroplast ATP-Synthase within the CF0CF1 Complex. 1. Distinction of Shielded and Exposed Surfaces of Delta on the Thylakoid Membrane
Authors: Berzborn Richard J. , Finke Werner
Published: August 2018

A new polyclonal antiserum against spinach CF1 subunit delta was produced in rabbits. It decorates only one band at 21 kDa in Western immunoblots of thylakoid proteins and does not react in ELISA with δ-free four subunit CF1 (-δ); therefore it is regarded monospecific. The polypeptide used as immunogen had been purified by HPLC. Earlier antisera against CF1 δ crossreact with CF1 subunit β.

The new antiserum 306 contains different antibodies; some can be absorbed with thylakoids, i.e. by δ within the assembled CF0CF1 complex on the membrane, others still react in ELISA with isolated CF1. The former antibodies agglutinate thylakoids and inhibit PMS cyclic photophosphorylation. Therefore we conclude that part of the surface of CF1 subunit δ is exposed within the quaternary structure of the ATP-synthase complex of photosynthetically active thylakoids, but part of the surface of δ is shielded.

Trypsination of isolated δ occurs at several sites, but this protease does not attack δ in situ, nor does aminopeptidase. Staphylococcus aureus protease V8 digests CF1 δ after isolation at residues Asp53, Glu61, Glu95 and Glu106, but has no access to these residues of δ in situ. Thus CF1 subunit δ seems to be shielded within the CF0CF1 complex to a large degree.

Direct agglutination of thylakoids by anti δ serum 306 was weak and could be improved tenfold by a Coombs serum (goat anti rabbit gammaglobulin), whereas an anti β serum agglutinated directly. From this we conclude that δ is not accessible at the top of the enzyme; the exposed part is extending below the large subunits a and β and oriented towards the membrane.
Pore-Forming Activity of Outer Membrane Extracts from the Unicellular Cyanobacterium Synechocystis sp. PCC 6714
Authors: Jürgens Uwe J. , Benz Roland
Published: August 2018

Cell walls of the unicellular cyanobacterium Synechocystis sp. PCC 6714, isolated from cell homogenates, were found to be unusually resistant against extraction with various detergents, organic solvents, chaotropic agents, and proteases. The major outer membrane proteins (M r 67,000; 61,000; 94,000) were solubilized by differential SDS-extraction and purified by preparative SDS-PAGE. The extracted proteins, reconstituted into lipid bilayer membranes, formed two types of pores with single-channel conductances of 2.2 nS (pore diameter of 1.4 nm) and 0.3 nS (pore diameter not determined), respectively. Carotenoids and lipopolysaccharide were found to be associated with the extracted major proteins.
3'-Arylazido-β-alanyl-2-azido ATP, a Cross-Linking Photoaffinity Label for F1ATPases
Authors: Schäfer Hans-Jochen , Rathgeber Gabriele , Dose Klaus
Published: August 2018

The synthesis of the 3′-arylazido-2-azido ATP derivative 3′-O-{3-[N-(4-azido-2-nitrophenyl)-amino]propionyl}2-azido-adenosine 5′-triphosphate (2,3′-DiN3ATP) is described. The bifunc­ tional photoreactive ATP analog is characterized spectroscopically. Photoaffinity labeling of F, ATPase from Micrococcus luteus by this analog results in the inactivation of the enzyme and in the formation of higher molecular weight cross-links,
Hg(II)-Induced Changes in DNA-Circular Dichroism: Reversible Transitions between Right-Handed and Left-Handed Screwness
Authors: Gruenwedel Dieter W.
Published: August 2018

Exposing native calf thymus DNA (in 0.1 м NaClO4-, 5 mм cacodylic acid buffer, pH 6.81, 25 °C) to increasing concentrations of Hg(C 104)2 produces dramatic changes in its circular dichroism (C D ). Let r = [mol of added Hg(II)*/[mol DNA base]: the conservative CD spectrum of the DNA B-form, consisting of the 273 nm major ( + ) C D band, the 245 nm major ( -) C D band, the 219 nm minor ( + ) CD band, and the 208 nm minor ( -) CD band, becom es non-conservative in appearance at 0.01 < r < 0.12 and assumes the spectral characteristics of a left-handed D N A double helix at 0.12 < r > 1.0. The presence of a number of isoellipticity points shows that welldefined equilibria exist between the various chiroptical forms of mercurated DNA . The CD changes are totally reversible upon the removal of H g(II), at least up to r = 1.0, demonstrating that H g(II) keeps all base pairs in register.
Heat Production and Growth Kinetics of E. coli K12 from Flow Calorimetric Measurements on Chemostat Cultures
Authors: Leiseifer H. P.
Published: August 2018

The heat production of E. coli K12 growing aerobically in glucose limited chemostat cultures is determined in the range of specific growth rates μ ( = dilution rates D) from 0,058 h-1 to 0.852 h-1 for two different glucose concentrations Se in the instream of the chemostat. namely Se1=0.3182 g·1-1 and Se2 = 0.6364 g·1-1. Heat production Q and biomass production P per unit of culture volume show well correlated patterns for Se1 and Se2. For Se1 the highest value Q actually measured is 443-10-3 W·1-1 at D = 0.74 h-1 with P = 0.068 g·1-1·h-1 and for Se2 593·10-3 W·1-1 at D = 0.497 h-1 with P = 0.108 g·1-1·h-1.

Heat production QB per unit of biomass appears to be independent of Se at least up to D - 0.5 h-1.At higher D there is strong indication that QB possesses a real maximum. The highest value of QB actually measured is 4.8 W·g-1 at D = 0.74 h-1.

For Se1 and Se2 there were significantly higher specific growth rates verified in chemostat culture than μmax
Batch= 0.717 h-1 which is the maximum specific growth rate in comparable, unlimited batch cultures.

The real maximum of QB is estimated to be in the vicinity of μmax
Batch.

This suggests the hypothesis of a maximum principle for the growth in batch culture.

For Se1 a closed analytical expression is derived for the relationship between μ and the substrate concentration S. μ[S] features a S-shaped characteristic with μmax
Chemostat= 0.905 h-1; 1/2 μmax
Chemostat is reached at S = 2.85·10-3 g·1-1.

Three basic parameters which characterize the overall metabolism of the cells, namely the heat released per unit of substrate consumed, (Qs, the effective yield of biomass, Yeff, and μmax
Chemostat are identified to depend on Se.
Swarming Phenomena, Basis of a Method to Identify Motile Bacteria Densitometrically
Authors: Blessing B. , Süssmuth R.
Published: August 2018

The swarming phenomenon of 18 strains was tested with the intention to identify motile, swarming bacteria. Not all bacteria which are motile in liquid are able to swarm on semisolid nutrient broth, but all swarming bacteria show characteristic swarming developments, resulting in different swarming zones which could be scanned densitometrically. The densitograms are fully reproducible for the same strain and show similarities between strains of one species.
Pentacyclic Triterpenoids in Epicuticular Waxes from Euphorbia lathyris L., Euphorbiaceae
Authors: Hemmers Herbert , Gülz Paul-Gerhard , Marner Franz-Josef , Wray Victor
Published: August 2018

The chemical composition of the leaf surface wax of Euphorbia lathyris L. was analysed using TLC, GC, GC-MS and NMR. A predominance of pentacyclic triterpenoids and primary alcohols was observed. They together constituted 60% of the total wax. Seven triterpenols: taraxerol, β-amyrin, lupeol, isomotiol, a-fernenol, simiarenol. Ψ-taraxasterol and eight triterpenones: taraxerone, β-amyrinone, lupenone, isomotione, a- and β-fernenone, simiarenone and filicanone were isolated. Among them , β-amyrin and lupeol were found esterified with homologous series of fatty acids. The minor part of wax was formed by long chained and predominantly saturated alkanes, wax esters, aldehydes and free fatty acids.
Lipid and Fatty Acid Composition of Synchronized Synechococcus leopoliensis
Authors: Döhler Günter , Datz Günter
Published: August 2018

The cyanobacterium Synechococcus leopoliensis (Anacystis nidulans, strain L 1402-1) grown at 39 °C and 2 vol. % CO : could be synchronized by a light/dark regime of 3:5 h (white light intensity 1.5 × 104 erg cm-2 sec-1). Content of pigments (chlorophyll a. phycocyanin and carotenoids), R N A and proteins increased linearly up to 100% at the end of the light period while DNA synthesis was lower. Chlorophyll a synthesis was correlated to the photosystem I activity of the isolated thylakoids and to the formation of MGD G . Galacto lipids were synthesized in the light period, only. A lag phase of 2h was observed in the biosynthesis of SQDG and PG. No significant differences were found between the cell and thylakoid fractions. Palmitic (C16:0), hexadecenoic (C16:1) and octadecenoic (C18:1) acid as major com ponents accounted for more than 90% of total fatty acids in MGD G , DGDG and SQDG . PG contains a small amount of stearic (C18:0) and heptadecenoic (C17:1) acid. No significant variations in the fatty acid distribution of all lipids could be detected in the cell fraction during the division cycle. Changes in the ratio of saturated to unsaturated fatty acids were found in isolated thylakoids. only. In experiments with [14C]bicarbonate main radioactivity was measured in galacto lipids while using [14C]acetate SQDG and PG were markedly [14C]labelled. Results were discussed with reference to the findings of eucaryotic algae and the formation of photosynthetic membranes.
Oxidative Ring-Cleavage of Catechol in meta-Position by Superoxide
Authors: Müller Rudolf , Lingens Franz
Published: August 2018

Superoxide reacts with catechol in dimethylsulfoxide to form a yellow product. The structure of this product was established by different methods. UV-spectra of the yellow compound corresponded under all circumstances to those of enzymatically produced 2-hydroxymuconic acid semialdehyde. In the presence of ammonia the product was converted to picolinic acid. The UV - spectra, the retention times in GC and HPLC and the mass spectra after methylation corresponded to those of authentic picolinic acid. Thus, the yellow reaction product was unequivocally identified as 2-hydroxymuconic acid semialdehyde. The formation of the me/a-cleavage product was only observed at low catechol concentrations (<2 mM) , at higher concentrations the product was not formed. The reaction was complete within 10 min at room temperature. Spectroscopic data suggest a first intermediate in the reaction with λmax = 804 nm, 772 nm and 660 nm.
Elongases Synthesizing Very Long Chain Monounsaturated Fatty Acids in Developing Oilseeds and Their Solubilization
Authors: Murphy Denis J. , Mukherjee Kumar D.
Published: August 2018

Particulate (15,000 x g ) fractions from developing seeds of mustard (Sinapis alba), honesty (Lunaria annua), and nasturtium (Tropaeolum majus) synthesize radioactive very long chain (n9)-(Z)-monounsaturated fatty acids, e.g. gadoleic (20:1). erucic (22:1). and nervonic (24:1) acids from [1-14C ]oleoyl-CoA with malonyl-CoA or from [2-14C]m alonyl-CoA with oleoyl-CoA . Pyridine nucleotides are required for the elongation reactions. Both NADH and NADPH are equally effective for the formation of 20:1, but NADPH is the preferred reductant for the formation of 22:1, which suggest the existence of separate elongase systems. Detergents, such as Triton X-100 and octyl thioglucoside, stimulate the elongation at low concentrations, but they are inhibitory at high concentrations. Partial solubilization of the elongase system using these detergents has been achieved.