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A 2642-base-pair DNA fragment containing the catalase T (CTT1) structural gene of the yeast Saccharomyces cerevisiae and its flanking regions has been sequenced. The gene codes for a protein of 562 amino acids (relative molecular mass 64,449) and appears to contain no intron. The amino acid sequence of catalase T derived from the DNA sequence shows 40.7% homology (52.2% including conservative replacements) to that of bovine liver catalase. All amino acids previously postulated to participate directly in catalysis by liver catalase and most of the amino acids of the immediate environment of hemin, the prosthetic group of catalase, are conserved in catalase T. The data obtained indicate that the folding of polypeptide chains of the two catalases compared has been conserved within a central region consisting mainly of the beta-barrel domain, which bears the prosthetic group, and a major part of the "wrapping domain". N- and C-terminal regions involved in subunit interactions are less well conserved. It is suggested that their structure is more similar to that of the corresponding regions of Penicillium vitale catalase. However, catalase T lacks the C-terminal flavodoxin-like domain present in this protein.  相似文献   

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Mating factor is a peptide excreted into the culture fluid by alpha-mating type cells of Saccharomyces cerevisiae X-2180 1B. The purification of the mating factor was carried out by ion exchange chromatography on phosphocellulose and Amberlite IRC 50 columns, followed by gel filtration on a Sephadex LH 20 column. The factor thus prepared was a peptide composed of Lys1, His1, Trp2, Gln2, Pro2, Gly1, Met1, Leu2 and Tyr1, and was able to induce morphological changes on alpha-mating type cells at a concentration of 5 pg/ml. The amino acid sequence of the mating factor was determined by the manual Edman degradation method using intact mating factor and its thermolytic peptides. The C-terminal amino acid residue was determined by digesting the factor with carboxypeptidase A. The complete amino acid sequence of the mating factor was established to be as follows: Trp-His-Trp-Leu-Gln-Leu-Lys-Pro-Gly-Gln-Pro-Met-Tyr.  相似文献   

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The crystallizable cytoplasmic aspartyl-tRNA synthetase from Saccharomyces cerevisiae is a dimer made up of identical subunits (Mr 63 000). Its primary structure was established using peptide sequences from four different digests of the native and citraconylated enzyme with trypsin, cyanogen bromide and staphylococcal protease. The oligonucleotide sequence of the structural gene was used as a template for the final alignment of the various peptides in the correct order.  相似文献   

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A positive regulatory sequence of the Saccharomyces cerevisiae ENO1 gene   总被引:5,自引:0,他引:5  
ENO1-'lacZ fusions with various lengths of the ENO1 5'-flanking region were constructed on various types of yeast plasmid vectors. The fully expressed level of beta Gal directed by ENO1-'lacZ fusions differed depending on the type of vector, but on any type of vector, beta Gal activity was not greatly influenced by the carbon source in the medium. The 86-bp DNA region of ENO1 at position -487 to -402 upstream of the initiation codon, in which we had previously delimited the positive regulatory region of ENO1 (Uemura, H., Shiba, T., Paterson, M., Jigami, Y., & Tanaka, H. (1986) Gene 45, 67-75), exerted its function without requiring precise location with respect to the TATA box. The action of the positive regulatory region was not affected by its orientation. In addition, the substitution of the UASs of PHO5, encoding repressible acid phosphatase, with the regulatory region of ENO1 changed the expression of PHO5-'lacZ gene to constitutive, irrespective of the concentration of inorganic phosphate in the medium. Furthermore, the GCR1 gene cloned in a multicopy plasmid increased the expression of the ENO1-'lacZ fused genes.  相似文献   

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The complete amino acid sequence of the nuclearly coded cytochrome c oxidase subunit VI was determined for a genetically defined haploid strain of Saccharomyces cerevisiae. The subunit contains 108 amino acids, has Mr = 12,627, is acidic (net charge of -9.7 at pH 7) and is quite polar (polarity index, 50.9%). Distribution of charges within the polypeptide chain is highly non-random. The NH2- and COOH-terminal regions are predominantly acidic whereas an apolar and a basic region are found in the interior, Subunit VI shows between 28 and 40% sequence homology (depending on the method of alignment) with subunit V of bovine cytochrome c oxidase; since the yeast subunit VI lacks methionine and contains only a single histidine residue very close to the NH2 terminus, it is unlikely that either of the two subunits carries heme alpha in the native enzyme.  相似文献   

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The nucleotide sequence of the oli1 gene encoding mitochondrial ATPase subunit 9 (76 amino acids) has been determined for five oligomycin-resistant mutants of Saccharomyces cerevisiae. Three of the mutations affect amino acids in the vicinity of the glutamic acid residue 59 at which dicylohexyl carbodiimide binds. Two other mutations lead to substitution of amino acid 23, which would lie very close to residue 59 in the folded hairpin conformation that this protein is thought to adopt in the inner mitochondrial membrane. The apposition of residues 23 and those adjacent to residue 59, lying respectively in the two hydrophobic membrane-spanning arms of subunit 9, is considered to constitute an oligomycin-binding domain. By consideration of the amino acid substitutions in those mutants cross-resistant to venturicidin, a domain of resistance for venturicidin is defined to lie within the oligomycin-binding domain, also centered on residues 23 and 59. These data also clarify the genetic recombination behaviour of alleles previously defined to form part of the oli3 locus (mutants characterized by resistance to both oligomycin and venturicidin) together with alleles defined to form part of the oli1 locus (mutants not cross-resistant to venturicidin). The oli1 and oli3 loci can now be seen to form two overlapping extended groups within the oli1 gene, with sequenced oli3 mutations being as far apart as 125 nucleotides within the subunit 9 coding region of 231 nucleotides.  相似文献   

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The gene encoding yeast phosphoglycerate mutase was isolated, and its sequence was determined. The gene specifies a protein of 246 amino acids, and contains no introns. The sequence shows a strong codon bias. The upstream untranslated portion of the gene contains a CT-rich block such as is found in many highly expressed yeast genes, but does not have the associated CAAG sequence.  相似文献   

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The yeast ADE 1 gene has been cloned and sequenced. The primary structure deduced from the nucleotide sequence demonstrated that phosphoribosylaminoimidazole-succinocarboxamide synthetase is a protein with molecular weight of 34 500 D.  相似文献   

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Among the members of the major facilitator superfamily of Saccharomyces cerevisiae, we identified genes involved in the transport into vacuoles of the basic amino acids histidine, lysine, and arginine. ATP-dependent uptake of histidine and lysine by isolated vacuolar membrane vesicles was impaired in YMR088c, a vacuolar basic amino acid transporter 1 (VBA1)-deleted strain, whereas uptake of tyrosine or calcium was little affected. This defect in histidine and lysine uptake was complemented fully by introducing the VBA1 gene and partially by a gene encoding Vba1p fused with green fluorescent protein, which was determined to localize exclusively to the vacuolar membrane. A defect in the uptake of histidine, lysine, or arginine was also observed in the vacuolar membrane vesicles of mutants YBR293w (VBA2) and YCL069w (VBA3). These three VBA genes are closely related phylogenetically and constitute a new family of basic amino acid transporters in the yeast vacuole.  相似文献   

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The data upon which the sequence of the 506 residues in the subunit of bovine liver catalase (BLC) is based are presented in detail. A partial sequence of bovine erythrocyte catalase (BEC) which accounts for 493 residues shows complete concordance with the BLC data. On the other hand, BEC has at least 517 residues, that is, an extension beyond the C terminus of the BLC data. Although normally BLC has only 506 residues, there is evidence that, at some point in its history, it also had the C-terminal extension. It is speculated that this extension is lost in BLC either through a different processing of the molecule in liver than in erythrocytes or by partial degradation in the first stages of catabolism.  相似文献   

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