bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloning, nucleotide sequence and functions of XPR6, which codes for a dibasic processing endoprotease from the yeast Yarrowia lipolytica
Authors: Enderlin Carol S. , Ogrydziak David M. 
Published: May 2005

AbstractYarrowia lipolytica DO613, carrying the xpr6‐13 mutation, secretes an inactive precursor of alkaline extracellular protease that has not been cleaved after the Lys‐Arg at the end of the pro‐region. Compared to wild type, DO613 membrane preparations had significantly reduced ability to cleave after Lys‐Arg of an artificial substrate. The XPR6 gene was cloned by complementation by screening for restoration of production of alkaline protease activity. Sequencing of a 3735 base pair SalI‐SphI XPR6 fragment revealed a large open reading frame with a coding capacity of 976 amino acids (molecular weight, 110 016). The deduced amino acid sequence had significant homology to Saccharomyces cerevisiae Kex2p, a processing endoprotease that cleaves after pairs of basic amino acids. Disruption of the XPR6 gene was not lethal, but it resulted in several phenotypic changes. First, essentially no mature alkaline extracellular protease was produced indicating that the low levels produced by strains carrying previously isolated xpr6 alleles were due to leaky mutations. Second, mating type B strains carrying the disrupted XPR6 gene did not mate, but mating type A strains did. Third, the XPR6 disruption strains grew poorly on rich media at pH 5·5 and above. Cells remained physically attached after budding and continued to bud forming large dog balloon‐like structures. In addition, these structures aggregated forming visible clumps in liquid culture. These growth aberrations were largely eliminated by growing cells in medium at pH 4. Fourth, no mycelial forms were observed regardless of the pH.
Structural modification of spindle pole bodies during meiosis II is essential for the normal formation of ascospores in Schizosaccharomyces pombe: Ultrastructural analysis of spo mutants
Authors: Hirata Aiko , Shimoda Chikashi 
Published: May 2005

AbstractIn order to characterize the morphological steps defined by sporulation (spo) genes during the formation of ascospores in the fission yeast Schizosaccharomyces pombe, we performed an electron microscopic study of the ultrastructure of the spindle pole body (SPB) and of the development of the forespore membrane during the second meiotic division (meiosis II) in sporulation‐deficient (spo) mutants (spo4, spo5, spo14 and spo18). No difference was found in terms of the function and the structure of the SPB during the first meiotic division (meiosis I) between the four mutants and wild‐type cells. However, during meiosis II, the spo4 and spo18 mutants underwent nuclear division but in neither case were the SPBs modified nor were forespore membranes formed. The SPBs of the spo18 mutant diminished in size after meiosis II and eventually disappeared after 18 h in sporulation medium. By contrast, the SPBs of the spo4 mutant remained unchanged even after an 18‐h incubation. The outer plaques of SPBs of spo5 and spo14 mutants were sufficiently modified to allow them to initiate development of the forespore membrane, but the membrane had an abnormally expanded lumen and did not enclose the nuclei during meiosis II. The spo5 mutant produced anucleate spore‐like bodies while the spo14 mutant formed unorganized structures with irregular peripheries which, presumably, contained spore‐wall precursors, instead of anucleate spore‐like bodies. We conclude that the modification of the SPB is essential for the formation of ascospores and at least two genes (spo5 and spo14) participate in the development of the forespore membrane. The defective phenotypes define discrete steps in the development of ascospores, which proceeds via steps defined by the mutant spo4, spo18, spo14 and spo5 genes respectively. Our observations provide further substantial evidence that the SPB plays a pivotal role in the normal development of ascospores in yeasts.
A general model of yeast energy metabolism in aerobic chemostat culture
Authors: Castrillo J. I. , Ugalde U. O. 
Published: May 2005

AbstractThe pattern of energy metabolism of different types of yeasts (obligate aerobes and facultative anaerobes) in aerobic chemostat cultures has been evaluated and interpreted on the basis of a coupling of metabolic fluxes between glycolytic and oxidative components.A model has been formulated which defines glycolytic and oxidative subunits through which the substrate C‐flux (gram‐atom g−1 h−1) is calculated, stating that a relative imbalance between glycolytic flux and subsequent oxidative steps alone is sufficient to account for the onset of oxidoreductive metabolism in any type of yeast, irrespective of the maximum respiratory capacity. The model is able to reproduce the patterns of behaviour reported for the different types of yeasts, and the individual features of each strain are explained on the basis of metabolic differences which are defined by a set of normalized parameters. The model can be applied to different substrates and conditions, providing a methodological basis for more detailed studies of the steps controlling yeast energy metabolism.
XI. Yeast sequencing reports. Sequence analysis of a 3·5 kb EcoRI fragment from the left arm of Saccharomyces cerevisiae chromosome XI reveals the location of the MBR1 gene and a sequence related to a GTPase‐activating protein
Authors: James Carolyn M. , Gent Manda E. , Oliver Stephen G. 
Published: May 2005

AbstractWe present the DNA sequence analysis of a region covering a 3·5 kb EcoRI fragment from the left arm of chromosome XI from Saccharomyces cerevisiae. This region contains five open reading frames (ORFs) which code for proteins of greater than 100 amino acids. ORF YKL425 codes for the previously sequenced Mbr1 (Valens et al., 1991; Daignan‐Fornier et al., 1993) which participates in mitochondrial biogenesis. YKL424 has identity with a GTPase‐activating protein of higher eukaryotes. The three remaining ORFs have no identity to known proteins within the databases screened and are not assigned ORF numbers as they are completely contained with ORFs YKL424 and YKL425. This sequence has been entered in the EMBL Data Library under Accession Number X75561.
XV. Yeast sequencing reports. A gene from Saccharomyces cerevisiae which codes for a protein with significant homology to the bacterial 3‐phosphoserine aminotransferase
Authors: Belhumeur Pierre , Fortin Nathalie , Clark Michael W. 
Published: May 2005

AbstractDuring the sequencing of the gene GSP2 from Saccharomyces cerevisiae, we have encountered an adjacent open reading frame having strong homology to the 3‐phosphoserine aminotransferase (E.C.2.6.1.52) from other organisms. In this report, we present the sequence for this yeast SERC, and evidence that its deletion from the yeast genome leads to serine dependency. The sequence has been deposited in the GenBank data library under Accession Number L20917.
Use of β‐lactamase as a secreted reporter of promoter function in yeast
Authors: Cartwright Charles P. , Li Yu , Zhu Yun‐Song , Kang Yoon‐Se , Tipper Donald J. 
Published: May 2005

AbstractK1 preprotoxin is the 316 residue precursor of the K1 killer toxin secreted by the yeast Saccharomyces cerevisiae. The SPβla reporter consists of the mature, secreted form of β‐lactamase (βla) fused to S and P, two fragments of preprotoxin. S is the N‐terminal 34 residues, including the secretion signal. P, a 67 residue ‘processing’ segment with three sites for N‐glycosylation, terminates in a Lys Arg site for cleavage by the Kex2 protease. Expression of SPβla in yeast results in efficient secretion, processing by signal peptidase and glycosylation in the endoplasmic reticulum, producing proßla. Kex2 cleavage of proßla in the lumen of a late Golgi compartment releases βla, which accumulates stably in culture media buffered at pH 5·8–7. The half‐life of secretion is 11 min at 30°C; 10–12% of the total activity in exponential‐phase cells is intracellular, mostly in the form of proßla, indicating that transit from the endoplasmic reticulum to the Golgi is rate limiting. We have used SPβla expression in single‐ and multi‐copy vectors to compare the PGK, GAL1, GAL10, PHO5 and CUP1 promoters under varying nutritional conditions. In exponential‐phase cells, secretion of βla over a 40‐fold range and up to several μg/ml was proportional to transcript level, demonstrating that SPβla can be employed as a convenient secreted reporter of promoter function in yeast.
I. Yeast sequencing reports. Isolation and characterization of the LEU2 gene of Hansenula polymorpha
Authors: Agaphonov Michael. O. , Poznyakovski Andrei I. , Bogdanova Aliona I. , Ter‐Avanesyan Michael D. 
Published: May 2005

AbstractA DNA fragment carrying the LEU2 gene of methylotrophic yeast Hansenula polymorpha was isolated by complementation of the leuB mutation of Escherichia coli. The nucleotide sequence of the isolated DNA fragment contains an open reading frame of 363 codons, coding for a protein 80% identical to the LEU2 gene product of Saccharomyces cerevisiae. Further downstream, there is a partial reading frame with no obvious similarity to known proteins. The LEU2 gene of H. polymorpha cannot complement the leu2 mutation of S. cerevisiae. The sequence has been entered in the EMBL data library under the Accession Number U00889.
I. Yeast sequencing reports. Sequencing of chromosome I of Saccharomyces cerevisiae: Analysis of the 42 kbp SP07‐CENI‐CDC15 region
Authors: Clark Michael W. , Keng Teresa , Storms Reg K. , Zhong Wuwei , Fortin Nathalie , Zeng Bin , Delaney Shawn , Ouellette B. F. Francis , Barton Arnold B. , Kaback David B. , Bussey Howard 
Published: May 2005

AbstractDetermination of the DNA sequence and preliminary functional analysis of a 42 kbp centromeric section of chromosome I have been completed. The section spans the SPO7‐CEN1‐CDC15 loci and contains 19 open reading frames (ORFs). They include an apparently inactive Ty1 retrotransposon and eight new ORFs with no known homologs or function. The remaining ten genes have been previously characterized since this part of the yeast genome has been studied in an unusually intensive manner. Our directed sequencing allows a complete ordering of the region. The sequence has been deposited in the GenBank data library under Accession Number L22015.
Saccharomyces cerevisiae mata mutant cells defective in pointed projection formation in response to α‐factor at high concentrations
Authors: Yorihuzi Tetuya , Ohsumi Yoshinori 
Published: May 2005

AbstractWe have isolated Saccharomyces cerevisiae MATa mutant cells that do not form a pointed projection but elongate in response to α‐factor at high concentrations. Complementation tests defined three genes, PPF1, PPF2, and PPF3 (for pointed projection formation), necessary for pointed projection formation. Allelism tests with genes known to be needed for projection formation revealed that PPF1 is identical to SPA2, while PPF2 and PPF3 are not allelic to SST2, STE2, SPA2, BEM1 or SLK1/SSP31/BCK1. The morphology of MATa ppf mutants treated with high concentrations of α‐factor is similar to that of MATa PPF cells treated with α‐factor at low concentrations. Quantitative mating tests showed that PPF2 and PPF3 are not essential for mating in either MATa or MATα background. Monitoring of division arrest and expression of an α‐factor‐inducible gene revealed that mutations in the PPF genes do not affect the responses of MATa cells to low concentrations of α‐factor. Unlike wild‐type cells, the ppf mutants exhibited early recovery from α‐factor‐induced division arrest. Furthermore, vegetatively growing ppf3‐1 cells are slightly defective in cell separation of mother and daughter cells and in selection of the correct bud sites in all cell types. These results indicate that PPF2 and PPF3 are involved in the response to α‐factor at high concentrations and that PPF3 is also required for proper establishment of polarity in vegetative growth.
V. Yeast mapping reports. The MAG1 3‐methladenine DNA glycosylase gene is closely linked to the SPT15 TATA‐binding TFIID gene on chromosome V‐R in Saccharomyces cerevisiae
Authors: Xiao Wei , Penugonde Vasu , Rank Gerald H. 
Published: May 2005

AbstractThe MAG1 gene encodes a 3‐methyladenine DNA glycosylase, which is involved in DNA alkylation repair in Saccharomyces cerevisiae. The mag1 mutant is deficient in 3‐methyladenine DNA glycosylase activity and shows enhanced sensitivity to several monofunctional alkylating agents. MAG1 is allelic to MMS5. This gene has been previously located on chromosome V by chromosomal hybridization. We present physical and genetic mapping data here showing that the MAG1 gene is located on chromosome V‐R, proximal to and about 10 kilobase pairs away from the SPT15 gene coding for the yeast TATA‐binding protein TFIID.
Yeast exo‐β‐glucanases can be used as efficient and readily detectable reporter genes in Saccharomyces cerevisiae
Authors: Cid V. J. , Alvarez A. M. , Santos A. I. , Nombela C. , Sanchez M. 
Published: May 2005

AbstractYeast exo‐1,3‐β‐glucanases are secretable proteins whose function is basically trophic and may also be involved in cell wall glucan hydrolytic processes. Since fluorescein di(β‐D‐glucopyranoside) is a fluorogenic substrate detectable and quantifiable by flow cytometry, it was used for testing the ability of the EXG1 gene product of Saccharomyces cerevisiae and its homologous gene in Candida albicans to function as reporter genes. These open reading frames were coupled to different promoters in multicopy plasmids, and exoglucanase activity quantified at flow cytometry. Exoglucanases were found to be useful tools for the study of promoter regions in S. cerevisiae. This technique has the advantage over other reporter gene systems—such as β‐galactosidase fusions—that it does not require permeabilization of yeast cells and therefore it allows the recovery of viable cells—by sorting—after flow cytometry analysis.
Yeast sequencing reports. Comparison of INO1 gene sequences and products in Candida albicans and Saccharomyces cerevisiae
Authors: Klig Lisa S. , Zobel Pamela A. , Devry Christopher G. , Losberger Christoph 
Published: May 2005

AbstractThe sequence of the Candida albicans inositol biosynthetic gene, CaINO1, and its flanking regions is determined in this study. The largest open reading frame has a coding sequence of 1560 base pairs, corresponding to a predicted protein of 521 amino acids. Three primary transcriptional start sites are found 64, 57 and 52 base pairs upstream of the ATG translational start site at position 1374. Five stop codons exist in a cluster at the end of the coding region. Within the upstream region TATA and CAAT eukaryotic regulatory sequences are identified along with regions corresponding to a 10 base pair inositol/choline responsive element consensus sequence. Computer analysis of the DNA sequence shows strong homology to the Saccharomyces cerevisiae INO1 gene. A comparison of the deduced amino acid sequence of the C. albicans INO1 gene product, inositol‐1‐phosphate synthase, with its homolog in S. cerevisiae shows 64% identity and 77% similarity. The differences between the two proteins are most prominent in the N‐terminal regions. The sequence has been deposited in the GenBank/EMBL data library under Accession Number L22737.
XV. Yeast sequencing reports. Isolation and DNA sequence of the STE13 gene encoding dipeptidyl aminopeptidase
Authors: Anna‐arriola Sonia Santa , Herskowitz Ira 
Published: May 2005

AbstractWe have isolated a mutant which exhibits partial constitutivity for a‐specific gene expression in α cells. The wild‐type gene was cloned and demonstrated to be allelic to the STE13 gene, which encodes the dipeptidyl aminopeptidase involved in processing of the α‐factor prepropheromone. Thus, the mating defect of the ste13 mutations in α cells may result both from the production of incompletely processed α‐factor and from the increased expression of a‐specific genes.The STE13 open reading frame of 931 amino acids contains a putative membrane‐spanning segment near its amino terminus and is 31% identical to a second yeast dipeptidyl aminopeptidase (DAP2). A null mutant of STE13 has been constructed: it is viable and sporulation‐proficient. The sequence has been deposited in the GenBank data library under Accession Number L21944.
Cloning and sequencing of Schizosaccharomyces pombe car1 gene encoding arginase. Expression of the arginine anabolic and catabolic genes in response to arginine and related metabolites
Authors: Van Huffel C. , Dubois E. , Messenguy F. 
Published: May 2005

AbstractWe report here the cloning and sequencing of the gene encoding arginase (car1) from Schizosaccharomyces pombe. Since no arginase‐less strain exists in this organism, we cloned the gene by functional complementation of a car1 mutant strain from Saccharomyces cerevisiae. The S. pombe car1 gene encodes a 323 amino acids polypeptide sharing identity with arginases from different organisms. Measurements of arg3, arg11 and car1 mRNA under different growth conditions confirm the very weak repression by arginine of the two anabolic genes and show that the induction of arginase synthesis operates at a transcriptional level. The promoter of S. pombe car1 gene does not contain the ‘arginine boxes’ defined as the target of the ARGR‐MCM1 proteins in the promoters of the arginine co‐regulated genes in S. cerevisiae. The heterologous expression of S. pombe car1 gene in S. cerevisiae is independent of the ARGRII gene product (ArgRIIp/Arg81p). Determination of arginine, ornithine and citrulline intracellular concentrations shows the efficiency of the different controls operating in S. cerevisiae, and also indicates that in S. pombe enzyme compartmentation is not always sufficient to control the arginine metabolic flux.
Activation of trehalase during growth induction by nitrogen sources in the yeast Saccharomyces cerevisiae depends on the free catalytic subunits of camp‐dependent protein kinase, but not on functional ras proteins
Authors: Durnez Peter , Pernambuco Maria Beatriz , Oris Els , Argüelles Juan‐Carlos , Mergelsberg Hubert , Thevelein Johan M. 
Published: May 2005

AbstractAddition of a nitrogen‐source to glucose‐repressed, nitrogen‐starved G0 cells of the yeast Saccharomyces cerevisiae in the presence of a fermentable carbon source induces growth and causes within a few minutes a five‐fold, protein‐synthesis‐independent increase in the activity of trehalase. Nitrogen‐activated trehalase could be deactivated in vitro by alkaline phosphatase treatment, supporting the idea that the activation is triggered by phosphorylation. Yeast strains containing only one of the three TPK genes (which encode the catalytic subunit of cAMP‐dependent protein kinase) showed different degrees of nitrogen‐induced trehalase activation. The order of effectiveness was different from that previously reported for glucose‐induced activation of trehalase in glucose‐derepressed yeast cells. Further reduction of TPK‐encoded catalytic subunit activity by partially inactivating point mutations in the remaining TPK gene further diminished nitrogen‐induced trehalase activation, while deletion of the BCY1 gene (which encodes the regulatory subunit) in the same strains resulted in an increase in the extent of activation. Deletion of the RAS genes in such a tpkw1 bcy1 strain had no effect. These results are consistent with mediation of nitrogen‐induced trehalase activation by the free catalytic subunits alone. They support our previous conclusion that cAMP does not act as second messenger in this nitrogen‐induced activation process and our suggestion that a novel nitrogen‐induced signaling pathway integrates with the cAMP pathway at the level of the free catalytic subunits of protein kinase A. Western blot experiments showed that the differences in the extent of trehalase activation were not due to differences in trehalase expression. On the other hand, we cannot completely exclude that protein kinase A influences the nitrogen‐induced activation mechanism itself rather than acting directly on trehalase. However, any such alternative explanation requires the existence of an additional, yet unknown, mechanism for activation of trehalase besides the well‐established regulation by protein kinase A.
Analysis of β‐glucans and chitin in a Saccharomyces cerevisiae cell wall mutant using high‐performance liquid chromatography
Authors: Hong Zhi , Mann Paul , Shaw Karen J. , Didomenico Beth 
Published: May 2005

AbstractWe have previously shown that mutations in the yeast KNR4 gene resulted in pleiotropic cell wall defects, including resistance to killer 9 toxin, elevated osmotic sensitivity to SDS and increased resistance to zymolyase, a (1→3)‐β‐glucanase. In this report, we further demonstrated that knr4 mutant cells were more permeable to a chromogenic substrate, X‐GAL, suggesting that the mutant cell walls were leakier to certain non‐permeable molecules. To determine if these defects resulted from structural changes in the cell walls, we analysed the alkali‐insoluble cell wall components using HPLC assays developed for this purpose. Comparative analysis using four isogenic strains from a ‘knr4 disrupted’ tetrad demonstrated that mutant cell walls contained much less (1→3)‐β‐glucan and (1→6)‐β‐glucan; however, the level of chitin, a minor cell wall component, was found to be five times higher in the mutant strains compared to the wild‐type strains. The data suggested that the knr4 mutant cell walls were dramatically weakened, which may explain the pleiotropic cell wall defects.
VII. Yeast sequencing reports. Cloning and characterization of a sulphite‐resistance gene of Saccharomyces cerevisiae
Authors: Casalone Enrico , Colella Carlo M. , Daly Simona , Fontana Silvia , Torricelli Ilaria , Polsinelli Mario 
Published: May 2005

AbstractIn this paper we describe the cloning and sequencing of the gene (SUL1) responsible for sulphite resistance in a Saccharomyces cerevisiae mutant (Casalone et al., 1992). The deduced amino acid sequence predicted that the gene codes for a zinc‐finger protein with five fingers. Comparison of wild‐type and mutant gene sequences demonstrated that the mutation event was a transversion from C to G; as a consequence of the mutation a histidine substituted an aspartic acid, affecting directly the fourth finger structure. The SUL1 gene sequence corresponds to that of FZF1 gene (Breitwieser et al., 1993) to which no function was attributed. The sequence has been entered in the EMBL data library under Accession Number 77592.
Yeast sequencing reports. Cloning and DNA sequence of a Kluyveromyces lactis ERD1 homologue
Authors: Dean Neta 
Published: May 2005

AbstractThe ERD1 gene product is required for the correct localization of soluble proteins that normally reside in the endoplasmic reticulum (ER). Cell lacking ERD1 secrete resident ER proteins and, in addition, exhibit defects in the processing of glycoproteins. Here, the molecular characterization of the Kluyveromyces lactis ERD1 homologue is described. A comparison of the predicted sequences of the Saccharomyces cerevisiae and K. lactis Erd1 proteins indicates that they are about 30% identical and 50% similar in sequence. Despite low sequence identity, these proteins are predicted to be conserved structurally. Furthermore, the K. lactis protein can functionally complement an S. cerevisiae mutant containing a deletion of the entire ERD1 gene, indicating these two proteins are functional homologues. The GenBank data library Accession Number for the DNA sequence reported in this paper is UO4714.