bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial plasmid pBR322 sequences serve as upstream activating sequences in Saccahromyces cerevisiae
Authors: Sidhu Rajinder S. , Bollon Arthur P. 
Published: May 2005

AbstractThe expression of acid phosphatase (Apase) from PHO5 and MFα‐PHO5 hybrid genes is regulated by inorganic phosphate and mating type locus respectively, as well as the PHO4 and MATα1 gene products respectively. When PHO5 and MFα‐PHO5 hybrid genes were cloned in the BamHI site of the pBR322 sequence of the yeast shuttle vectors (YRp7 or YEp9T), in one orientation they were regulated normally but in the other orientation their expression was not regulated but expressed constitutively. The pBR322 sequences present upstream of the inserted genes are responsible for the constitutive expression. By replacing the PHO5 upstream activating sequences (UAS) element with pBR322 fragments, we have identified three pBR322 sequences, rom nucleotides 376 to 650, 2068 to 2116 and 2136 to 2247, which were able to promote expression of APase. A comparison of these three pBR322 fragments revealed 5′ ATCGCGCGAG 3′ and 5′ CGGTGATGNCGG 3′ to be the common sequences likely to act as USAs in Saccharomyces cerevisiae. By using synthetic oligonucleotides, it was found that both sequences are required for maximum expression of APase activity.
Mapping of the trifunctional fatty acid synthetase gene FAS2 on chromosome XVI of Saccharomyces cerevisiae
Authors: Siebenlist Ursula , Nix Johanna , Schweizer Michael , Jäger Daniel , Schweizer Eckhart 
Published: May 2005

AbstractThe trifunctional FAS2 gene encoding subunits α of the Saccharomyces cerevisiae fatty acid synthetase complex was mapped on the left arm of chromosome XVI 24 centinorgans proximal to GAL4 and 39 centimorgans distal and PEP4 relative to the centromere. Mapping was achieved by three‐independent methods: meiotic co‐segragation of FAS2 and ARO7 in recombination‐deficient spo11‐mutants; tetrad analysis of crosses between FAS2, GAL4 and PEP4; and Southern hybridization of purified FAS2 DBA with individual yeast chromosomes separated by pulsed‐field gel electrophoresis.
Mating type locus‐dependent stability of the Kluyveromyces linear pGKL plasmids in Saccharomyces cerevisiae
Authors: Gunge Norio , Murakami Kazuo , Takesako Tosikazu , Moriyama Hideaki 
Published: May 2005

AbstractThe linear killer plasmids, pGKL1 and pGKL2, from Kluyveromyces lactis stably replicated in mitochondria1 DNA‐deficient (ρ0) MATa or MATα haploids of Saccharomyces cerevisiae, but were unstable and frequently lost in ρ° MATa/MATα diploids, suggesting that the replication of pGKL plasmids was under the control of the MAT locus. In MATa/MATα cells of S. cerevisiae, the MATα gene product (α2) is combined with the MATa gene product (a1) and the resultant protein, a1‐α2, acts to repress the expression of haploid specific genes. Experiments showed that the K. lactis linear plasmids were stably maintained in ρ0 mata1/MATα diploids, indicating that the a1‐α2 repressor interfered with the stability of pGKL2. It was revealed by computer analysis that the consensus sequence homologous to the a1‐α2 repressor binding site occurred within the coding regions of pGKL2 genes which were presumed to be essential for the plasmid replication. Since the plasmids were stably maintained in diploids of K. lactis, the mating type control must not be working there.
Assembly of amine oxidase and D‐amino acid oxidase in the cytosol of peroxisome‐deficient mutants of the yeast Hansenula polymorpha during growth of cells on glucose in the presence of primary amines or D‐alanine as the sole nitrogen source
Authors: Sulter G. J. , Van Der Klei I. J. , Harder W. , Veenhuis M. 
Published: May 2005

AbstractWe have studied growth of two peroxisome‐deficient mutant strains of Hansenula polymorpha on glucose in the presence of different organic nitrogen sources (methylamine, ethylamine and D‐alanine), the metabolism of which is mediated by peroxisome‐borne oxidases in wild‐type (WT) cells. Both strains grew well on each of these substrates with growth rates comparable to WT cells. Growth on both methylamine and ethylamine was associated with enhanced levels of catalase and amine oxidase in the cells; in D‐alanine‐grown cells D‐amino acid oxidase activity and increased. In WT cells of H‐polymorpha the activities of these enzymes were confined to the peroxisomal matrix; however, in both peroxisome‐deficient strains their activities were localized in the cytosol. Electron microscopy indicated that, dependent on the stage of growth, the enzymes may form large protein aggregates.The molecular masses of both amine oxidase and D‐amino acid oxidase in the mutant strains were identical to their respective counterparts in WT cells, indicating that both proteins were correctly assembled and active in the cytosol.
Mapping of the ARS‐like activity and transcription initiation sites in the non‐canonical yeast mitochondrial ori 6 region
Authors: Delouya Daniel , Nobrega Francisco G. 
Published: May 2005

AbstractThe insert‐containing, non‐canonical ori 6 region of yeast mitochrondrial DNA of Saccharomyces cerevisiae was dissected into 15 different segments that were ligated to the integrative yeast vector YIp5. Six recombinant plasmids exhibited replicative ability in yeast and carried consensus sequences similar to the previously described 11 bp motifs active as autonomous replication sequences (ARS). In addition, all active constructions carry one or more of the characteristic GC‐rich domains A, B or C present in the ori 6 region, thus confirming and expanding the study of Blanc (Gene 30 (1984) 47–61) with the canonical ori 5. Also a new transcriptional origin is activated in the ori 6 region, apparently circumventing a disruption by insertion of a GC‐rich sequence that, in this ori, removes the mitochondrial promoter usually present next to the Celement. The ARS‐positive constructions correspond to the retained segments of spontaneous well‐characterized suppressive or neutral petite genomes that contain segments of the ori sequence.
Phylogenetic relationships among species of Saccharomyces, Schizosaccharomyces, Debaryomyces and Schwanniomyces determined from partial ribosomal RNA sequences
Authors: Kurtzman Cletus P. , Robnett Christie J. 
Published: May 2005

AbstractSpecies of the genera Saccharomyces, Schizosaccharomyces, Debaryomyces and Schwanniomyces were compared from their extent of divergence in three regions from small (18S) and large (25S) subunit ribosomal RNAs comprising a total of 900 nucleotides. With the exception of the closely related Saccharomyces bayanus and S. pastorianus, which appear to have identical sequences, all other species could be distinguished by nucleotide differences in a variable region of the large subunit, and genus‐specific nucleotides were discernible in all three regions. The taxon D. tamarii differed markedly from other species and is excluded from Debaryomyces. By contrast, Schwanniomyces occidentalis showed few nucleotide differences with Debaryomyces spp. and its transfer to Debaryomyces is proposed. Schizosaccharomyces proved to be somewhat more divergent than Saccharomyces and Debaryomyces, but species differences appear insufficient for dividing the genus. Some of the factors influencing estimates of phylogenetic distances from rRNA sequences are discussed.
Synthesis of superoxide dismutase, catalase and other enzymes and oxygen and superoxide toxicity during changes in oxygen concentration in cultures of brewing yeast
Authors: Clarkson Simon P. , Large Peter J. , Boulton Christopher A. , Bamforth Charles W. 
Published: May 2005

AbstractThe physiological effects on brewing yeast, growing in semi‐defined wort medium, of a sudden transition from aerobiosis to anaerobiosis were studied. Two yeast strains were examined, used for ale and lager fermentations respectively. The reverse transition (from anaerobiosis to aerobiosis) was also examined. Transitions were applied by changing the sparging gas during growth or in stationary phase, and the effects on the specific activities of certain key enzymes and on the viability of the cultures were examined.Neither type of transition led to significant changes in growth rate, the rate of ethanol production or the specific activities of alcohol dehydrogenase and pyruvate decarboxylase. The most significant change was in the specific activity of CuZn‐superoxide dismutase, which showed a rapid increase in activity on transition from anaerobiosis to aerobiosis, and a decrease in activity on the reverse transition. Catalase activity in the ale yeast generally followed that of CuZn‐superoxide dismutase, whereas in the lager yeast it remained unchanged by the transitions. The transition from anaerobiosis to aerobiosis caused increases in citrate synthase and Mn‐superoxide dismutase, though only after a significant lag period. Aerobic to anaerobic transitions caused a decrease in Mn‐superoxide dismutase activity, while citrate synthase remained unchanged.Anaerobically grown cells showed a rapid loss in viability on exposure to oxygen (5–7% in the first hour), while aerobically grown cells were unaffected. When anaerobically grown cells were exposed to 0·25 mM‐potassium superoxide, there was an 8% loss of viability within 10 min, whereas aerobic cells were not affected.It is concluded that the toxic effect of oxygen is due to superoxide (or a species derived from it) and that the CuZn‐superoxide dismutase (but not the Mn‐isoenzyme) plays a role in protecting the cells. The de novo synthesis of the CuZn‐enzyme is not always rapid enough to confer full protection.
Hydrogen peroxide as an electron acceptor for mitochondrial respiration in the yeast Hansenula polymorpha
Authors: Verduyn Cornelis , Van Wijngaarden Connie J. , Alexander Scheffers W. , Van Dijken Johannes P. 
Published: May 2005

AbstractChemostat cultures of a catalase‐negative mutant of Hansenula polymorpha CBS 4732 were able to decompose hydrogen peroxide at a high rate. This was apparent from experiments in which yeast was grown under carbon limitation in chemostat culture on mixtures of glucose and H2O2. The enzyme responsible for H2O2 degradation is probably the mitochondrial enzyme cytochrome c peroxidase (CCP), which was present at very high activities. This enzyme was partially purified and shown to be specific for reduced cytochrome c as an electron donor; no reaction was observed with NAD(P)H. Thus, reducing equivalents for H2O2 degradation by CCP must be provided by the respiratory chain.That H2O2 can act as an electron acceptor for reducing equivalents could be confirmed with experiments in which cells were incubated with ethanol and H2O2 in the absence of oxygen. This resulted in oxidation of ethanol to equimolar amounts of acetate.Energetic aspects of mitochondrial H2O2 decomposition via CCP and the physiological function of CCP in yeasts are discussed.
Ribosomal DNA spacer probes for yeast identification: Studies in the genus Metschnikowia
Authors: Henriques Marília , Sá‐Nogueira Isabel , Giménez‐Jurado Gabriella , Van Uden N. 
Published: May 2005

AbstractTo test whether DNA probes derived from ribosomal DNA spacer sequences are suitable for rapid and species‐specific yeast identification, a pilot study was undertaken. A 7·7 kb entire ribosomal DNA unit of the type strain of Metschnikowia reukaufii was isolated, cloned and mapped. A 0·65 kb BamHI‐HpaI fragment containing nontranscribed spacer sequences was amplified and selected for testing as a 32P hybridization probe with total DNA from the type strains of M. reukaufii, M. pulcherrima, M. lunata, M. bicuspidata, M. australis, M. zobellii, M. krissii, five other strains identified as M. reukaufii and strains of Schizosaccharomyces pombe, Hansenula canadensis, Saccharomyces cerevisiae and Yarrowia lipolytica. The probe hybridized exclsively with DNA from the type strain and four other strains of M. reukaufii. DNA from one strain labelled M. reukaufii did not hybridize with the probe. Subsequent % G+C comparison and DNA–DNA reassociation with the type strain revealed that the non‐hybridizing strain does not belong to the species M. reukaufii.
Inositol biosynthesis: Candida albicans and Saccharomyces cerevisiae genes share common regulation
Authors: Klig Lisa S. , Antonsson Bruno , Schmid Elisabeth , Friedli Laurence 
Published: May 2005

AbstractThe Candida albicans inositol biosynthetic gene and its regulation have been studied. The gene, CalNO1, was cloned on a multicopy vector by complementation of a Saccharomyces cerevisae mutant strain. Southern blot analysis established that the cloned DNA was C. albicans genomic DNA in origin; neither rearrangements nor pseudogenes were evident. Blot hybridization analysis using RNA isolated from C. albicans revealed that a single RNA species (1·8 kilobases) was homologous to the cloned DNA fragment. The steady‐state levels of these transcripts were shown to be regulated in response to inositol in the growth media. In addition, the steady‐state levels of the RNA encoded by the cloned C. albicans DNA present in S. cerevisiae on a plasmid (YRpCalNO1) were regulated in response to exogenously provided inositol. The cloned C. albicans DNA fragment was shown to restore inositol‐1‐phosphate synthase activity to a S. cerevisiae mutant strain defective in this enzyme. This activity was also shown to be regulated in response to the presence of inositol in the growth media.
III. Yeast sequencing reports. Sequence of the CDC10 region at chromosome III of Saccharomyces cerevisiae
Authors: Steensma H. Yde , Van Der Aart Quirina J. M. 
Published: May 2005

AbstractA 4·74 kb DNA fragment from the right arm of chromosome III of Saccharomyces cerevisiae, adjacent to the centromere region was sequenced. Four open reading frames with an ATG initiation codon and larger than 200 bp were found in this fragment. The largest open reading frame of 966 bp was identified as the CDC10 gene.
Assignment of most genes encoding major peroxisomal polypeptides to chromosomal band V of the asporogenic yeast Candida tropicalis
Authors: Kamiryo Tatsuyuki , Mito Naruo , Niki Toshiro , Suzuki Takahito 
Published: May 2005

AbstractThe peroxisomes of the asporogenic yeast Candida tropicalis contain about 20 major polypeptides (PXPs). We have isolated a number of genes encoding them; 11 POX genes encoded independent PXPs and three POY genes were likely to encode three other PXPs. To locate these genes on the chromosomes, chromosomes of C. tropicalis were separated by pulsed‐field gel electrophoresis. Eight chromosomal bands were observed over the range of 1·0 Mbp (band I) to 2·8 Mbp (band VIII); the genome size was estimated to be about 20 Mbp. Southern blot analysis showed that ten genes were on band V, three genes were on band IV, and the other gene was on band VI. Three genes gave hybridization signals of nearly equal intensity on two different chromosomal bands: POX6A and POX8B, on bands V and VII; and POX8A, on bands IV and VI. Ribosomal RNA genes also hybridized to two bands, VI and VII. Most genes assigned to only one band hybridized to two restriction fragments produced by either NotI or SfiI endonuclease. The results suggested that C. tropicalis was diploid and that restriction sites were conserved little between homologues. The three POX genes that were found on two chromosomal bands hybridized to not more than two restriction fragments, implying that the allelic genes were present on different chromosomal bands.
Genetic transformation of auxotrophic mutants of the filamentous yeast Trichosporon cutaneum using homologous and heterologous marker genes
Authors: Ochsner Urs A. , Glumoff Virpi , Kälin Markus , Fiechter Armin , Reiser Jakob 
Published: May 2005

AbstractA transformation system for the filamentous yeast Trichosporon cutaneum based on auxotrophic markers is presented and techniques for the induction, isolation and characterization of mutants are described. A number of auxotrophic mutants were isolated and characterized by using biosynthetic precursors and/or inhibitors. A mutant unable to grow in the presence of ornithine could be complemented successfully in spheroplast transformation experiments using the cloned Aspergillus nidulans ornithine transcarbamoylase gene (argB gene) as selection marker with an efficiency of 5–100 transformants per μg of DNA. In these transformants the heterologous argB gene was present in multiple tandem copies and the transforming DNA was found to remain stable after more than 50 generations in non‐selective media. The same mutant could be complemented by a T. cutaneum cosmid gene library and a complementing cosmid was subsequently isolated from this library by a sib‐selection strategy. This cosmid transformed. T. cutaneum spheroplasts with an efficiency of 50–200 colonies per μg of DNA. Southern blot analyses were consistent with the view that the transforming sequences became stably integrated into the host genome at the homologous site.
Yeast flocculation: Flo1 and NewFlo phenotypes and receptor structure
Authors: Stratford Malcolm , Assinder Stephen 
Published: May 2005

AbstractFlocculation characteristics of 42 flocculet strains of Saccharomyces cerevisiae were examined. Two entirely distinct ‘lectin‐like’ mechanisms of flocculation were distinguished by sugar, salt, and low pH inhibitions, protease sensitivity, and selective expression of flocculation. One group, termed Flo1 phenotype, was inhibited by mannopyranoses and contained all strains bearing known genes affecting flocculation. The other group, termed NewFlo phenotype, contained the majority of brewery ale strains and was inhibited by manno‐ and glucopyranoses. Detailed sugar‐inhibition work revealed the probable receptor identity of both Flo1 and NewFlo flocculation, as being non‐reducing termini of α‐(1–3)‐linked mannan side branches, two or three mannopyranose residues in length.
The ureidoglycollate hydrolase (DAL3) gene in Saccharomyces cerevisiae
Authors: Yoo Hyang Sook , Cooper Terrance G. 
Published: May 2005

AbstractThe DAL3 gene has been sequenced and found to encode a 195 amino acid protein with a molecular weight of 21 727. The four carboxy‐terminal amino acids of DAL3 product (Cys‐Ile‐Ile‐Ile) are homologous to those (CAAX) previously shown to be the primary structural signal for post‐translational farnesylation of yeast RAS protein and mating factor. This modification is reported to be responsible for membrane localization of proteins containing it. The upstream region of DAL3 contains six copies of a sequence that is homologous to the positively acting DAL UASNTR reported to be required for transcriptional activation of the DAL5 and DAL7 genes. Missing from the DAL3 upstream region were any sequences related to those shown to be required for a DAL7 response to inducer, the UIS element. This correlates with the previous report that DAL3 expression is independent of the allantoin pathway inducer.
Selective inactivation of alcohol oxidase in two peroxisome‐deficient mutants of the yeast Hansenula polymorpha
Authors: Van Der Klei I. J. , Harder W. , Veenhuis M. 
Published: May 2005

AbstractWe have studied selective inactivation of alcohol oxidase (AO) in two peroxisome‐deficient (PER) mutants of the yeast Hansenula polymorpha. In these mutants high activities of cytosolic AO are induced by different growth conditions. At enhanced expression rates AO is arranged in large crystalloids in the cytosol, whereas smaller crystalloids are often observed inside the nucleus. Transfer of cells of the PER mutant 125‐2E, which completely lacks peroxisomes, to glucose‐excess conditions did not lead to degradative inactivation of AO and catalase as observed in wild‐type (WT) cells used as a control. The gradual decrease in enzyme activities in the PER mutant could be accounted for by dilution of existing enzyme into newly formed cells as a result of growth. Morphologically, degradation of the cytosolic crystalloids was also not observed. Similar results were obtained with a second PER mutant (strain 124‐2D), impaired in the import of peroxisomal matrix proteins. This mutant is characterized by the presence of small peroxisomes and large cytosolic AO crystalloids. Upon a shift of cells to glucose‐excess conditions only part of the small peroxisomes present in these cells were degraded by mechanisms similar to those observed in WT cells placed under identical conditions. These results indicate that degradative inactivation of AO in H. polymorpha is strictly dependent on the localization of the enzyme inside peroxisomes and furthermore suggests that the mechanisms triggering this process are not directed against AO protein, but instead, to the membrane surrounding the organelle. Transfer of cells to methanolor ethanol‐containing media both resulted in modification inactivation of AO. Under these conditions also the AO crystalloids remained unaffected by incubation in the new environment.
The major exoglucanase from Candida albicans: A non‐glycosylated secretory monomer related to its counterpart from Saccharomyces cerevisiae
Authors: Luna‐Arias Juan P. , Andaluz Encarnación , Ridruejo Juan C. , Olivero Isabel , Larriba Germán 
Published: May 2005

AbstractExoglucanases secreted by two different strains from Candida albicans have been purified to homogeneity. The purified enzyme from each strain behaved as a non‐glycosylated monomer (molecular weight 38 000) that was identical in terms of sodium dodecyl sulphate/polyacrylamide gel electrophoresis comigratin, amino acid analysis and amino terminal sequence. The amino acid composition was similar to that of the major exoglucanase from Saccharomyces cerevisiae. In addition, these two enzymes displayed a 50% homology in the first 35 amino acids of the amino terminus. Antibodies against the deglycosylated exoglucanase (treated with Endo H) from S. cerevisiae were reactive with the exoglucanase from C. albicans and vice versa. Immunoblotting proved to be a semiquantitative method to detect C. albicans antigen in culture fluids. The exoglucanase from C. albicans appears to enter the secretory pathway without undergoing N‐glycosylation.
Regulation of cystathionine γ‐lyase in Saccharomyces cerevisiae
Authors: Ono Bun‐Ichiro , Naito Kazuhide , Shirahige Yoh‐Ichi , Yamamoto Mahoko 
Published: May 2005

AbstractRegulation of the two enzymes in reverse trans‐sulfuration was investigated in Saccharomyces cerevisiae. In wild‐type strains, cystathionine γ‐lyase, but not cystathionine β‐synthase, was derepressed nearly 15‐fold if cells were starved for both inorganic and organic sulfur compounds. In a met17 strain which is defective of O‐acetylserine and O‐acetylhomoserine sulfhydrylase, the same enzyme was derepressed if organic sulfur compounds were limited; the repressive effect was in the order of glutathione > methionine > cysteine. The repressive effect of methionine was not observed, however, in a cys2 cys4 strain which is deficient of serine O‐acetyltransferase and cystathionine β‐synthase, indicating that methionine itself is not the effector. The weak repressive effect of cysteine was attributed to inefficient uptake of this amino acid.Our observations indicate that cystathionine γ‐lyase is the target of regulation in reverse trans‐sulfuration and that cysteine is very likely to be the effector of this regulation.
The PHO80/TUP7 locus in Saccharomyces cerevisiae is on the left arm of chromosome XV: Mapping by chromosome engineering
Authors: Kawasaki Hideki , Matsuzaki Hiroaki , Nakajima Ryoichi , Oshima Yasuji 
Published: May 2005

AbstractThe PHO80/TUP7 locus in Saccharomyces cerevisiae is reported to be located on the right arm of chromosome XV close to its centromere. In the present study, the locus has been reassigned to the left arm of the same chromosome by reciprocal recombination between chromosomes V and XV at URA3 (on chromosome V) and PHO80/TUP7 loci by using the site‐specific recombination system of the yeast plasmid pSR1.