| the association of the autoantigens of primary biliary cirrhosis with the mitochondrial h+-atpase--a reassessment. | the claimed association between the m2 autoantigens of primary biliary cirrhosis (pbc) and the mitochondrial h+-atpase has been re-examined in view of the recent reports that pbc autoantibodies react specifically with the lipoate acetyl transferases of 2-oxo acid dehydrogenases. study of f0f1-atpase purified from human and yeast mitochondria, and the comparison between immunoprecipitates obtained with antibodies against the h+-atpase beta subunit and anti-m2 antibodies of pbc, established that t ... | 1989 | 2528956 |
| increased plasma and erythrocyte selenium concentrations but decreased erythrocyte glutathione peroxidase activity after selenium supplementation in children with down syndrome. | an investigation was made of the activity of glutathione peroxidase (gsh-px) in erythrocytes and the levels of selenium in plasma and erythrocytes before, during and after selenium supplementation in children with down syndrome (ds). this subject is of interest since it has been suggested that selenium supplementation could enhance the gsh-px activity in erythrocytes, probably leading to improved protection against oxygen radicals, which might cause damage by lipid peroxidation, especially in th ... | 1989 | 2532445 |
| reactivation of neutron killed mammalian cells by gamma irradiation: the observations, possible mechanism and implication. | we have observed that combinations of neutron plus gamma ray exposure can significantly increase the colony forming ability of monkey and human cell cultures over the neutron dose alone. the "reactivation" of neutron killed mammalian cells by gamma rays is analogous to observations made in lower eukaryotic organisms and fits the pattern termed "t repair" previously postulated for yeast and protozoans. | 1990 | 2300886 |
| [human epidermal growth factor gene is expressed in saccharomyces cerevisiae]. | saccharomyces cerevisiae was transformed with plasmids containing the synthetic hegf gene under control of a alpha-factor promoter. the expressed protein was efficiently secreted into the medium broth and was shown to be a biologically active hegf. | 1989 | 2534612 |
| deficient lysosomal carboxypeptidase activity in galactosialidosis. | in the lysosome, the glycosidases neuraminidase (ec 3.2.1.18) and beta-galactosidase (ec 3.2.1.23) are associated to a 52 kda "protective protein" to form a large multi-enzymatic complex. deficient synthesis or inactivation of this protective protein causes galactosialidosis, a lysosomal storage disorder in man in which both neuraminidase and beta-galactosidase activities are deficient. since the protective protein possesses extensive sequence homology with carboxypeptidase y (carb y) and the ke ... | 1990 | 2328002 |
| [circulating immune complexes and myasthenia gravis (analysis of 78 cases)]. | for the sake of studying the circulating immune complexes (cic) of 78 patients with myasthenia gravis (mg), the agglutination assay of c3b sensitized with yeast cell (c3bsyca) was used. the anti human c3 elisa was also used for 21 out of the 78 patients. the positive results in the entire group of the patients studied were found to reach 82% and the igg and igm cic were detected also with anti-human c3 elisa. the titres of cic thus determined decreased as the clinical conditions improved. it was ... | 1990 | 2390882 |
| occurrence of s-(1,2-dicarboxyethyl)-cysteine at position 77 in mutant human lysozyme secreted by saccharomyces cerevisiae. | a mutant human lysozyme p110, in which val110 was replaced with pro, was secreted by saccharomyces cerevisiae; modification of the cysteine residue at position 77 was found in a purified mutant protein (p110-b) upon primary structure analysis. a peptide fragment containing 15 amino acid residues from thr70 to leu84 was obtained by proteolytic digestion of the protein and subsequently isolated by reverse-phase hplc. this fragment was analyzed by high-resolution fast-atom-bombardment (fab) mass sp ... | 1990 | 2404763 |
| protein n-myristoylation in escherichia coli: reconstitution of a eukaryotic protein modification in bacteria. | protein n-myristoylation refers to the covalent attachment of a myristoyl group (c14:0), via amide linkage, to the nh2-terminal glycine residue of certain cellular and viral proteins. myristoyl-coa:protein n-myristoyltransferase (nmt) catalyzes this cotranslational modification. we have developed a system for studying the substrate requirements and biological effects of protein n-myristoylation as well as nmt structure-activity relationships. expression of the yeast nmt1 gene in escherichia coli ... | 1990 | 2406721 |
| construction of yeast artificial chromosome libraries with large inserts using fractionation by pulsed-field gel electrophoresis. | a method for constructing yeast artificial chromosome (yac) libraries with large insert sizes is reported. high molecular weight human dna was partially digested with ecori and cloned in the vector pyac4. when unfractionated dna was used, the mean yac size was 120kb. fractionation by pulsed-field gel electrophoresis using a 'waltzer' apparatus to remove small dna fragments increased the mean yac size to congruent to 220kb or congruent to 370kb depending on the fractionation conditions. ligated d ... | 1989 | 2542900 |
| expression of hepatitis b virus surface antigen p31 gene in yeast. | the hepatitis b virus surface antigen (hbsag) p31 gene has been expressed in yeast saccharomyces cerevisiae. the gene products were shown to be glycoproteins with molecular sizes of 37,000 and 34,000 daltons (gp37 and gp34) containing polymerized albumin receptors. successfully detecting these proteins depended on the extraction procedures. in the extract without protein denaturants and inhibitors, these products were degraded rapidly by proteases to yield smaller size derivatives lacking polyme ... | 1986 | 2427075 |
| prenylation of mammalian ras protein in xenopus oocytes. | ras protein requires an intermediate of the cholesterol biosynthetic pathway for posttranslational modification and membrane anchorage. this step is necessary for biological activity. maturation of xenopus laevis oocytes induced by an oncogenic human ras protein can be inhibited by lovastatin or compactin, inhibitors of the synthesis of mevalonate, an intermediate of cholesterol biosynthesis. this inhibition can be overcome by mevalonic acid or farnesyl diphosphate, a cholesterol biosynthetic in ... | 1990 | 2233726 |
| mapping of the active site tyrosine of eukaryotic dna topoisomerase i. | dna topoisomerase i from the yeasts saccharomyces cerevisiae and schizosaccharomyces pombe was overproduced using the cloned genes. extracts from cells overproducing dna topoisomerase i were prepared and incubated with 32p-labeled dna. alkali was used to trap the topoisomerase i-dna covalent intermediate. most of the dna was digested with nuclease, and the resultant 32p-labeled topoisomerase i was subjected to cleavage with cyanogen bromide or formic acid. from the molecular weights of the resul ... | 1989 | 2547758 |
| complementary dna encoding core protein ii of human mitochondrial cytochrome bc1 complex. substantial diversity in deduced primary structure from its yeast counterpart. | core protein ii of mitochondrial cytochrome bc1 complex is the second largest nuclear-encoded subunit that is essential for the assembly of the functional complex. we have isolated, for the first time, a cdna clone for a mammalian core protein ii. immunoscreening of a lambda gt11 rat liver cdna library resulted in isolation of a cdna encoding a partial sequence of rat mitochondrial core protein ii, and this cloned cdna was used as a probe for colony hybridization to screen a human fibroblast cdn ... | 1989 | 2547763 |
| isolation and characterization of a human telomere. | a method is described that allows cloning of human telomeres in s. cerevisiae by joining human telomeric restriction fragments to yeast artificial chromosome halves. the resulting chimeric yeast-human chromosomes propagate as true linear chromosomes, demonstrating that the human telomere structure is capable of functioning in yeast and suggesting that telomere functions are evolutionarily conserved between yeast and human. one cloned human telomere, yht1, contains 4 kb of human genomic dna seque ... | 1989 | 2549507 |
| production and immunological analysis of recombinant hepatitis b vaccine. | the synthesis of the hepatitis b surface antigen (hbsag) in cells of saccharomyces cerevisiae and its subsequent isolation, purification and analysis is described. the final, purified hbsag particle exhibits close structural and biochemical similarities to particles derived from the plasma of chronically infected humans. particles of yeast and human origin have been found, by chimpanzee efficacy studies and by various in vitro analyses, to be immunologically equivalent. the antigenic expression ... | 1986 | 2427590 |
| novel hepatitis b vaccines. | development of vaccines against hepatitis b has proceeded along four main lines. human plasma-derived vaccines are safe, effective, and in general use. subunit polypeptide vaccines formulated in micelles have reached the stage of clinical trials. recombinant dna vaccines have been produced in prokaryotic and eukaryotic cells, notably in yeast. the yeast-derived recombinant vaccine has proved safe and effective in extensive clinical trials, eliciting antibodies of equal quantity and quality of sp ... | 1986 | 2427591 |
| molecular cloning of human uracil-dna glycosylase, a highly conserved dna repair enzyme. | uracil-dna glycosylase is the dna repair enzyme responsible for the removal of uracil from dna, and it is present in all organisms investigated. here we report on the cloning and sequencing of a cdna encoding the human uracil-dna glycosylase. the sequences of uracil-dna glycosylases from yeast, escherichia coli, herpes simplex virus type 1 and 2, and homologous genes from varicella-zoster and epstein-barr viruses are known. it is shown in this report that the predicted amino acid sequence of the ... | 1989 | 2555154 |
| [structure and expression of human hepatitis b virus surface antigen]. | in view of the growing occurrence rate of the virus-induced hepatitis b and also of the special role played by this particular virus (hbv) in the application of recombinant genetic techniques to the study of complex biological systems, an attempt was made to survey the available evidence concerning the widely investigated and practically the most important part of the viral genome, viz. the gene coding for the surface antigen (hbsag) and the protein itself. the possible antigenic structure of th ... | 1986 | 2429171 |
| biochemical and cellular determinants of bleomycin cytotoxicity. | bleomycin is a mixture of cytotoxic glycopeptides which function as mininucleases, binding to dna and producing single and double strand breaks by the formation of an activated oxygen complex. bleomycin is an effective agent against a few human cancers, notably lymphomas, testicular and ovarian germ cell cancers and certain squamous carcinomas. most human cancers are resistant to bleomycin a priori, however, and those which are initially sensitive frequently develop resistance to the drug during ... | 1986 | 2439200 |
| construction of expression vectors for the production of interferons in yeast. | expression vectors designed for the production of foreign proteins in yeast are constructed as a composite of functional dna segments brought together in a single plasmid dna molecule. such a composite dna molecule constitutes a complex entity in terms of its replication and selection functions (in both e. coli and s. cerevisiae) and its gene expression properties. the latter depend critically upon transcriptional control signals (the promoter and terminator regions from a highly expressed yeast ... | 1987 | 2440740 |
| a 20s particle ubiquitous from yeast to human. | we have purified and characterized a particle sedimenting at 20s from the postribosomal fraction of yeast, wheat germ, drosophila melanogaster tissue culture cells, chicken embryo fibroblasts, rabbit reticulocyte lysate, and hela cells. most of the protein constituents of the 20s particle have molecular weights of 20-35 kd and differ between species; however, some do have similar molecular weights and isoelectric points, suggesting they are related. several low-molecular-weight rnas, distinct fr ... | 1987 | 2443724 |
| immunological cross-reactivity of alcohol dehydrogenase (adh) isozymes with rabbit immune sera against horse and human adh subunits. | rabbit immune sera raised against denatured forms of horse liver alcohol dehydrogenase and of human adh5 isozyme were found to react with the denatured subunits of all the human adh isozymes regardless of their class. the immune serum against the human adh isozyme cross-reacted also with horse adh subunits and, at appropriate dilutions, both the immune sera reacted with denatured yeast adh, suggesting that common structures have been preserved in these molecules over a long evolutionary period. ... | 1986 | 2451467 |
| clinical experience with a recombinant dna hepatitis b vaccine. | the clinical testing of engerixr-b, the hepatitis b vaccine produced by smithkline biologicals using recombinant dna technology, started in february 1984. since extensive pre-clinical laboratory work had established that the polypeptide (hbsag) expressed in genetically engineered yeast cells was after purification--physically, chemically and antigenically similar to the viral surface antigen particles found in the blood of chronic carriers, the aims of the clinical trials were to compare the saf ... | 1988 | 2464196 |
| yeast-expressed granulocyte-macrophage colony-stimulating factor in cancer patients: a phase ib clinical study. | the in vivo effect of yeast-derived recombinant human granulocyte-macrophage colony-stimulating factor (rhgm-csf) was investigated in 29 patients with advanced malignancy in phase ib trial. patients were treated at six different dose levels (30-1000 micrograms/m2/day) with either daily intravenous bolus injection or 24 hours continuous infusion for 5 days or 2 weeks. administration of rh gm-csf resulted in a broad spectrum of dose-, route-, and schedule-dependent hematopoietic effects. sustained ... | 1988 | 2467645 |
| identification and characterization of an rna molecule that copurifies with rnase p activity from hela cells. | an rna molecule, 340 nucleotides in length and designated h1 rna, copurifies with rnase p activity from extracts of hela cells or isolated hela cell nuclei. when the genomic dna of various organisms is probed with h1 cdna in southern hybridization assays, only mammalian dna gives a positive signal. the gene coding for h1 rna in human cells is present in one to three copies per cell. the nucleotide sequence of h1 rna, which shows little homology to the known sequences of its analogs from prokaryo ... | 1989 | 2470644 |
| high levels of oral yeasts in early hiv-1 infection. | ten human immunodeficiency virus-1 (hiv-1) infected homosexual or bisexual individuals (ages 24-45) with no history of opportunistic infection were examined, by culture, for the presence of yeasts in whole saliva and on oral mucosa. all were hiv-1 antibody-positive men, non-smokers, non-denture wearers, and taking no medication. the mean salivary level of yeast was four logs higher in the hiv-1 infected group compared to a control group of normal, unmedicated, non-smoking men (ages 20-41) who de ... | 1989 | 2575167 |
| conserved pattern of antisense overlapping transcription in the homologous human ercc-1 and yeast rad10 dna repair gene regions. | we report that the genes for the homologous saccharomyces cerevisiae rad10 and human ercc-1 dna excision repair proteins harbor overlapping antisense transcription units in their 3' regions. since naturally occurring antisense transcription is rare in s. cerevisiae and humans (this is the first example in human cells), our findings indicate that antisense transcription in the ercc-1-rad10 gene regions represents an evolutionarily conserved feature. | 1989 | 2471070 |
| fine structure analysis of the chinese hamster as gene encoding asparagine synthetase. | overlapping cdnas for chinese hamster ovary (cho) asparagine synthetase (as) were isolated from a library prepared from an as-overproducing cell line. the sequence was determined and shown to contain an open reading frame encoding a protein of mr 64,300. the predicted amino acid sequence for the cho as enzyme was compared to that of the human as enzyme and found to be 95% homologous. a potential glutamine amide transfer domain, with sequence similarity to amidotransferases from bacteria and yeas ... | 1989 | 2477309 |
| synthesis of small nuclear ribonucleoprotein particles by the malarial parasite plasmodium falciparum. | sera from patients with autoimmune diseases have been used to identify small nuclear ribonucleoprotein particles (snrnps) present in higher eukaryotic cells and also in dinoflagellates. previously these sera have not detected crossreactive snrnp protein antigens of other lower eukaryotes such as yeast, tetrahymena, or dictyostelium. we report that anti-sm, anti-u1-rnp, and anti-la/ss-b human antisera react with specific snrnp protein antigens synthesized by the protozoan plasmodium falciparum, t ... | 1985 | 2582421 |
| proliferating cell nuclear antigen/cyclin in the ciliate euplotes eurystomus: localization in the replication band and in micronuclei. | human autoimmune sera specific for proliferating cell nuclear antigen (pcna)/cyclin (auxiliary protein for dna polymerase delta) demonstrated the presence of epitopes within the macro- and micronuclei of the hypotrichous ciliated protozoa euplotes eurystomus. tightly bound pcna/cyclin was localized at the site of dna synthesis in macronuclei, the rear zone of the replication band. starvation or heat shock, conditions that reduce macronuclear replication, resulted in a decrease of pcna/cyclin in ... | 1989 | 2477376 |
| conserved repetitive epitope recognized by cd4+ clones from a malaria-immunized volunteer. | t cell clones obtained from a human volunteer immunized with plasmodium falciparum sporozoites specifically recognized the native circumsporozoite (cs) antigen expressed on p. falciparum sporozoites, as well as bacteria- and yeast-derived recombinant falciparum cs proteins. the response of these cd4+ cd8- cells was species-specific, since the clones did not proliferate or secrete gamma interferon when challenged with sporozoites or recombinant cs proteins of other human, simian, or rodent malari ... | 1989 | 2480642 |
| characterization and expression of the human rhoh12 gene product. | the rho genes constitute an evolutionarily conserved family having significant homology to the ras oncogene family. these genes have been found in saccharomyces cerevisiae, drosophila melanogaster, rat, and human; their 21,000-dalton products show strong conservation of structure. in humans, three classes of rho cdna clones have been identified which differ by virtue of the presence of variable c-terminal domains: rhoh12, rhoh6, and rhoh9. the predicted 193 amino acids of human rhoh12 protein sh ... | 1989 | 2501657 |
| recombinant soluble fc epsilon receptor ii (fc epsilon rii/cd23) has ige binding activity but no b cell growth promoting activity. | we have undertaken the production of recombinant soluble fc epsilon receptor ii (fc epsilon rii) as a secretory protein, but not as a cleavage product of membrane-bound receptor. several plasmid constructs containing soluble receptor sequence were prepared. only a chimeric gene containing the sequences encoding il-6 signal peptide and the soluble moiety of fc epsilon rii could be expressed in xenopus laevis oocytes and cho cells, resulting in the secretion of soluble fc epsilon rii. the recombin ... | 1989 | 2523938 |
| the application of molecular biology to the development of novel vaccines. | in summary, we have shown that yeast is the preferred host for the expression of recombinant-derived hepatitis b vaccines, and that a yeast expression system which is productive, stable and scaleable can be developed for each of the three hbv envelope proteins. the versatility of regulated and integrated yeast expression systems in the production of foreign polypeptides with biomedical utility also has been highlighted. we also have shown that careful attention to the development of recombinant ... | 1989 | 2532858 |
| inhibition of leishmania donovani promastigote internalization into murine macrophages by chemically defined parasite glycoconjugate ligands. | leishmania donovani, the agent of human visceral leishmaniasis, is an intracellular parasite that must be recognized and internalized by host macrophages to complete its biological cycle. in a search for possible ligands for macrophage surface receptors, glycoconjugates were obtained from leishmania promastigotes by aqueous, phenol-aqueous, and alkaline extraction. a fucose-mannose glycoproteic ligand, a lipopeptidephosphoglycan, and a phosphate mannogalactan ligand were purified from promastigo ... | 1989 | 2537257 |
| mammalian camp-responsive element can activate transcription in yeast and binds a yeast factor(s) that resembles the mammalian transcription factor anf. | the human atf and ap1 transcription factors bind to highly related dna sequences. their consensus binding sites differ by a single nucleotide, but this single change is crucial in determining factor binding specificity. we have previously identified an ap1 (yap1) binding activity in yeast. in this report we identify a yeast atf (yatf) binding activity whose specificity can be distinguished from that of yap1 by the same crucial nucleotide that distinguishes binding of human atf and ap1. the atf b ... | 1989 | 2538834 |
| epstein-barr virus bzlf1 trans-activator specifically binds to a consensus ap-1 site and is related to c-fos. | two regions of the epstein-barr virus bzlf1 trans-activator protein have sequence similarity to the c-fos protein. part of the similarity corresponds to the region of c-fos which is similar to the dna binding domain of c-jun and gcn-4. the structure of the exon which contains this region in c-fos and bzlf1 is also highly conserved between the two genes. complete bzlf1 protein and a c terminal fragment were prepared either as purified fusion proteins or by in vitro translation from a bzlf1 cdna. ... | 1989 | 2540954 |
| the cdc2 kinase is a nuclear protein that is essential for mitosis in mammalian cells. | a homolog of the fission yeast cdc2-encoded protein kinase (p34) is a component of m phase promoting factor in xenopus oocytes. the homologous kinase in human hela cells is maximally active during mitosis, suggesting a mitotic role in mammalian somatic cells. this has been directly investigated by microinjection of anti-p34 antibodies into serum-stimulated rat fibroblasts. dna synthesis was unaffected but cell division was quantitatively blocked in injected cells. injection of antibodies against ... | 1989 | 2541912 |
| isolation of single-copy human genes from a library of yeast artificial chromosome clones. | a recently developed cloning system based on the propagation of large dna molecules as linear, artificial chromosomes in the yeast saccharomyces cerevisiae provides a potential method of cloning the entire human genome in segments of several hundred kilobase pairs. most application of this system will require the ability to recover specific sequences from libraries of yeast artificial chromosome clones and to propagate these sequences in yeast without alterations. two single-copy genes have now ... | 1989 | 2544027 |
| the ras oncogene--an important regulatory element in lower eucaryotic organisms. | the ras proto-oncogene in mammalian cells encodes a 21-kilodalton guanosine triphosphate (gtp)-binding protein. this gene is frequently activated in human cancer. as one approach toward understanding the mechanisms of cellular transformation by ras, the function of this gene in lower eucaryotic organisms has been studied. in the yeast saccharomyces cerevisiae, the ras gene products serve as essential function by regulating cyclic adenosine monophosphate metabolism. stimulation of adenylyl cyclas ... | 1989 | 2547147 |
| a brief overview of the new vaccines against hepatitis b virus infection: immunogenic gene products and peptide analogues of antigenic epitopes. | immunologically recognizable antigens encoded by hepatitis b virus (hbv) dna include: (i) the surface antigen (hbsag), (ii) the pre-s antigen, (iii) the x antigen (hbxag) and (iv) the core/e antigens (hbcag/hbeag). each one of these antigens or their combination may be prepared for the next generation of vaccines against hbv infection. the synthesis of hbsag by expression of recombinant dna in the yeast system has now reached the stage of clinical trials and will certainly provide the first alte ... | 1986 | 2427376 |
| expression of human dna topoisomerase i in yeast cells lacking yeast dna topoisomerase i: restoration of sensitivity of the cells to the antitumor drug camptothecin. | yeast saccharomyces cerevisiae strains that are permeable to the antitumor alkaloid camptothecin are killed by the drug if they express dna topoisomerase i, the cellular target of the drug (j. nitiss and j.c. wang, proc. natl. acad. sci. usa, 85: 7501-7505, 1988). we show that in a yeast strain permeable to camptothecin but lacking dna topoisomerase i, sensitivity to the drug was restored upon expression of human dna topoisomerase i from a plasmid-borne human complementary dna clone. when the hu ... | 1989 | 2553253 |
| phosphatidylinositol 3-kinase and its novel product, phosphatidylinositol 3-phosphate, are present in saccharomyces cerevisiae. | the metabolism of polyphosphoinositides has been shown to be an important factor in controlling the proliferation of saccharomyces cerevisiae. the monophosphate form of phosphatidylinositol has been assumed to be phosphatidylinositol 4-phosphate (pi-4-p). recent evidence from our laboratory has established that a phosphatidylinositol (pi) kinase, which phosphorylates the d-3 position of the inositol ring (pi 3-kinase), is associated with many activated protein-tyrosine kinases and may play an im ... | 1989 | 2555343 |
| fungispecificity of fluconazole against candida albicans. | candida albicans is an opportunistic pathogen of human mucosal surfaces. colonization of oral and vaginal mucosa by this yeast is antagonized by the resident normal bacterial population. however, antibacterial therapy can alter the normal flora to allow fungal cells to attach, grow and invade host tissues. we studied the antimicrobic activity of fluconazole against clinical isolates of oral and vaginal bacteria and candida albicans in vitro and in vivo by scanning and transmission electron micro ... | 1989 | 2559330 |
| [identification of human porins. ii. characterization and primary structure of a 31-lda porin from human b lymphocytes (porin 31hl)]. | we characterize and describe for the first time the primary structure of a human porin with the molecular mass of 31 kda derived from the plasmalemm of b-lymphocytes (porin 31hl). porin 31hl is shown to be a basic, channel forming membrane protein. the protein chain is composed of 282 amino acids with a relative molecular mass of 30641 da without derivatisation. it is not a glycoprotein. the n-terminus is acetylated. altogether the amino-acid sequence shows 56% hydrophilic or charged amino acids ... | 1989 | 2559745 |
| expression of three recombinant homodimeric isoforms of pdgf in saccharomyces cerevisiae: evidence for difference in receptor binding and functional activities. | three recombinant homodimeric isoforms of platelet-derived growth factor (pdgf) were produced and purified in milligram quantities by expression of pdgf a- and b-chains in yeast cells. structural analysis of the purified short and long variants of pdgf-aa (pdgf-aas and pdgf-aal) and pdgf-bb showed that they had been properly processed and assembled into dimers. pdgf-aas and pdgf-aal were found to bind only to the pdgf a-type receptor on human fibroblasts, with affinities of 0.1 and 0.2 nm, respe ... | 1989 | 2560933 |
| transmembrane signalling in saccharomyces cerevisiae. | baker's yeast, a unicellular eukaryote, has been a model organism for biochemists, geneticists and most recently for molecular biologists. pioneering biochemical studies were conducted on yeast, such as the study of glucose fermentation and amino acid metabolism. the powerful tools of yeast genetics have allowed a comprehensive study of important issues such as the cell cycle and meiosis. in recent years, it has been established that saccharomyces cerevisiae, the most extensively characterized o ... | 1989 | 2561938 |
| the poly(a)-poly(a)-binding protein complex is a major determinant of mrna stability in vitro. | using an in vitro mrna decay system, we investigated how poly(a) and its associated poly(a)-binding protein (pabp) affect mrna stability. cell extracts used in the decay reactions were depleted of functional pabp either by adding excess poly(a) competitor or by passing the extracts over a poly(a)-sepharose column. polyadenylated mrnas for beta-globin, chloramphenicol acetyltransferase, and simian virus 40 virion proteins were degraded 3 to 10 times faster in reactions lacking pabp than in those ... | 1989 | 2565532 |
| molecular cloning of a chinese hamster mitochondrial protein related to the "chaperonin" family of bacterial and plant proteins. | the complete cdna sequence of a mitochondrial protein from chinese hamster ovary cells, designated p1, which was originally identified as a microtubule-related protein (gupta, r.s., ho, t.k.w., moffat, m.r.k., and gupta, r. (1982) j. biol. chem. 257, 1071-1078), has been determined. the p1 cdna encodes a protein of 60,983 da including a 26-amino acid putative mitochondrial targeting sequence at its n-terminal end. the deduced amino acid sequence of chinese hamster p1 shows 97% identity to the hu ... | 1989 | 2568357 |
| structure, expression and chromosomal localization of zfp-1, a murine zinc finger protein gene. | zinc finger proteins (zfp) are encoded by a large family of genes present in many organisms including yeast and human. some of them are transcriptional activators and bind specifically to dna by zinc mediated folded structures commonly known as zinc fingers. the drosophila krüppel (kr) is a segmentation gene and encodes a zinc finger protein. using a probe from the finger domain of kr, we have isolated a structurally related gene zfp-1 from the mouse. in this paper, we report the complete nucleo ... | 1989 | 2574853 |
| coping with stress. international workshop on genetic response to environmental adversity sponsored by the national institute of child health and human development, airlie, va, usa april 23-26, 1989. | | 1989 | 2577344 |
| the effect of the secretory leukocyte protease inhibitor on leukocyte proteases released during phagocytosis. | the human secretory leukocyte protease inhibitor effectively binds and blocks the digestive activity of elastase released from pmn leukocytes during phagocytosis of opsonized yeast particles. about 25% of the alpha 1-protease inhibitor present in the incubation medium is inactivated during the phagocytosis, while the secretory leukocyte protease inhibitor retains more than 90% of its inhibiting capacity. | 1988 | 2578013 |
| the c-cbl proto-oncogene is preferentially expressed in thymus and testis tissue and encodes a nuclear protein. | cas ns-1 is an acutely transforming murine retrovirus that induces early b-lineage lymphomas and occasional myeloid leukemias. the transforming sequence of this virus, v-cbl, shows no homology to known oncogenes but has some similarities to the yeast transcriptional factor gcn4. in this study we used a v-cbl probe to analyze mrnas from a wide range of murine and human hemopoietic tumor cell lines and detected an 11-kilobase mrna in all lineages. in normal mouse tissues the expression of c-cbl wa ... | 1989 | 2585608 |
| excystation and culture of giardia spp. from human source. | in this paper, we report the hatching of giardia spp. trophozoites from purified cysts harvested in sheather's solution from human feces. isolated cysts were induced by acidic hank's balanced salt solution (hbss), incubated at 37 degrees c for 30 minutes, concentrated by centrifugation and washed with ph 7.5 hbss. the cysts were placed in 8 ml. culture medium (pancreatic digest of casein and yeast extracts) supplemented with human serum and bile in borosilicate glass tubes with screw caps. troph ... | 1989 | 2604494 |
| [the proteins of human mixed saliva in galvanism and yeast-induced stomatitis]. | mixed salivary pools of normal subjects and patients with galvanism, yeast-induced stomatitis, and diabetes mellitus were examined. the examinations have revealed elevated alpha-amylase levels in the patients with galvanism and still higher levels of this enzyme in yeast-induced stomatitis and diabetes mellitus. these diseases are also associated with a rise of lactoferrin content and with appearance of fibrinogen degradation products. | 1989 | 2623695 |
| [vaccination as a means of prevention]. | while recognizing the fact that the use of strict hygienic techniques, disposable materials and quality control are essential for sterilizing instruments, vaccination still remains the most efficient way to combat infection. in this article, the authors discuss the principle problems associated with the use of vaccines and especially as they relate to the dental office. hepatitis b is certainly of interest to all dentists and their personnel, especially since its primary mode of transmission is ... | 1989 | 2630580 |
| nonmutagenic carcinogens induce intrachromosomal recombination in yeast. | to identify environmental carcinogens there is a need for inexpensive and reliable short-term tests, but certain human or animal carcinogens are persistently undetectable as mutagents with the ames assay or with other short-term tests currently in use. thus there is a need for short-term tests which detect carcinogens missed by the ames assay. because of the association of carcinogenesis with genome rearrangement, a system screening for intrachromosomal recombination resulting in genome rearrang ... | 1989 | 2643057 |
| characterization of antithrombins produced by active site mutagenesis of human alpha 1-antitrypsin expressed in yeast. | both congenital and acquired antithrombin-iii (at-iii) deficiencies are amenable to replacement therapy. we describe two antithrombins produced by recombinant dna techniques from human alpha 1-antitrypsin (alpha 1at) cdna in yeast. alteration of the alpha 1at active site, replacing methionine 358 with arginine, results in a thrombin inhibition rate similar to that of heparin-activated at-iii. alteration of two further residues, to give a five-residue sequence identical to at-iii, does not increa ... | 1989 | 2644977 |
| autonomously replicating episomes contain mdr1 genes in a multidrug-resistant human cell line. | gene amplification in human tumor cells is frequently mediated by extrachromosomal elements (e.g., double minute chromosomes [dms]). recent experiments have shown that dms can be formed from smaller, submicroscopic circular precursors referred to as episomes (s. m. carroll, m. l. derose, p. gaudray, c. m. moore, d. r. needham-vandevanter, d. d. von hoff and g. m. wahl, mol. biol. 8:1525-1533, 1988). to investigate whether episomes are generally involved as intermediates in gene amplification, we ... | 1989 | 2648129 |
| colorimetric detection of specific dna segments amplified by polymerase chain reactions. | the polymerase chain reaction (pcr) procedure has many potential applications in mass screening. we describe here a general assay for colorimetric detection of amplified dna. the target dna is first amplified by pcr, and then a second set of oligonucleotides, nested between the first two, is incorporated by three or more pcr cycles. these oligonucleotides bear ligands: for example, one can be biotinylated and the other can contain a site for a double-stranded dna-binding protein. after linkage t ... | 1989 | 2648402 |
| yeast mutants conferring resistance to toxic effects of cloned human insulin-like growth factor i. | the production of extracellular human insulin-like growth factor i (igf-i) in yeast is deleterious to the growth of the host organism. mutants resistant to the toxic effects of igf-i production were isolated. a subset of these mutants produced levels of igf-i greater than the parent strain and were due to chromosomal recessive mutations at a single locus, hpx1. the overproduction of igf-i was independent of the original promoter and vector expression system. the mutant strains also displayed enh ... | 1989 | 2687116 |
| expression of a human p-450iic gene in yeast cells using galactose-inducible expression system. | a cdna of a human liver cytochrome p-450, corresponding to p-450 human-2, was expressed in saccharomyces cerevisiae cells by the use of a galactose-inducible expression vector containing the gal7 promoter and terminator. in western blots using anti-p-450 human-2 igg, a single band, which exhibited mobility identical to that of authentic p-450 human-2 purified from human liver, was detected in microsomes of the yeast cells. the amount synthesized in yeast was estimated to be approximately 1% of t ... | 1989 | 2649791 |
| current biotechnological developments in belgium. | in recent years, actions have been undertaken by the belgian government to promote process innovation and technical diversification. research programs are initiated and coordinated by the study committee for biotechnology setup within the institute for scientific research in industry and agriculture (irsia). as a result of this action, the main areas where biotechnological processes are developed or commercially exploited include plant genetics, protein engineering, hybridoma technology, biopest ... | 1989 | 2650884 |
| dominant yeast and mammalian ras mutants that interfere with the cdc25-dependent activation of wild-type ras in saccharomyces cerevisiae. | two mutant alleles of ras2 were discovered that dominantly interfere with wild-type ras function in the yeast saccharomyces cerevisiae. an amino acid substitution which caused the dominant interference was an alanine for glycine at position 22 or a proline for alanine at position 25. analogous mutations in human h-ras also dominantly inhibited ras function when expressed in yeast cells. the inhibitory effects of the mutant ras2 or h-ras genes could be overcome by overexpression of cdc25, but onl ... | 1989 | 2651897 |
| evidence that xeroderma pigmentosum cells from complementation group e are deficient in a homolog of yeast photolyase. | xeroderma pigmentosum (xp) patients are deficient in the excision repair of damaged dna. recognition of the dna lesion appears to involve a nuclear factor that is defective in complementation group e (xpe binding factor). we have now identified a factor in the yeast saccharomyces cerevisiae that shares many properties with xpe binding factor, including cellular location, abundance, magnesium dependence, and relative affinities for multiple forms of damaged dna. yeast binding activity is dependen ... | 1989 | 2689872 |
| the structure of the escherichia coli hemb gene. | the escherichia coli hemb gene, which encodes 5-aminolevulinic acid dehydratase, and was cloned into ptz18u, a multicopy plasmid, was sequenced. the hemb insert was double-digested with restriction enzymes and recloned back into ptz18u and ptz19u to allow for sequencing in two directions. in a second procedure, used to fill in gaps and to confirm the sequence derived from the first procedure, the whole insert was cloned into m13 phages. a nested set of deletions was constructed and recloned into ... | 1989 | 2656410 |
| temporary complementation of temperature-sensitive mutants of the cell cycle by transfection with a wild-type or a mutant cdna of adp/atp translocase. | a number of cell-cycle-specific temperature-sensitive (ts) mutants have been isolated from animal cells, especially syrian hamster cells. these ts mutants, like cell cycle ts mutants of yeast, can be complemented by specific genes, some of which have been molecularly cloned. we have isolated a cdna clone that complements tk-ts13 cells, but only temporarily. this clone, called b1, differs from a previously isolated clone (sekiguchi et al.: embo journal 7:1683-1687, 1988) that specifically complem ... | 1989 | 2550485 |
| structural analysis of phospho-d-mannan-protein complexes isolated from yeast and mold form cells of candida albicans nih a-207 serotype a strain. | the immunochemical properties between phospho-d-mannan-protein complexes of yeast (y) and mycelial (m) forms of candida albicans nih a-207 (serotype a) strain were compared. hydrolysis of the y-form complex gave a mixture of beta-(1----2)-linked d-mannooligosaccharides consisting mainly of tri- and tetra-ose, whereas the m-form complex gave preponderantly d-mannose. the antiserum against y-form cells exhibited a lower reactivity with the m-form than with the y-form complex, whereas the antiserum ... | 1989 | 2663154 |
| point mutations modifying the thrombin inhibition kinetics and antithrombotic activity in vivo of recombinant hirudin. | the hirudin variant hv2 was modified by in vitro site-specific mutagenesis of hv2 cdna to generate hv2(asn-47----lys), hv2(asn-47----arg) and hv2(lys-35----thr, asn-47----lys). residues 35 and 47 are positioned respectively within the finger and prothrombin-like domains of hirudin, both of which have been suggested as thrombin binding sites. the modified polypeptides were synthesized in saccharomyces cerevisiae using a secretion vector and purified from culture supernatants. by analysis of the h ... | 1989 | 2710782 |
| characterization of ribonucleolytic activity of angiogenin towards trna. | yeast trna is a convenient substrate for the assay of the ribonucleolytic activity of human angiogenin. the optimal ph, [nacl], and temperature for trna cleavage by angiogenin are approximately 6.8, 15-30 mm, and approximately 55 degrees c, respectively, as compared with approximately 8.0, 100-200 mm, and approximately 65 degrees c, respectively, for rnase a. polyanions and metals both inhibit angiogenin and rnase a but to different extents. | 1989 | 2730651 |
| [rapid chemiluminescence analysis of the effect of drugs on the functional activity of phagocytosing blood cells]. | the effects of 46 drugs on luminol-dependent chemiluminescence of human whole blood leucocytes during phagocytosis were studied. anti-inflammatory agents, antihistaminics and anticoagulants inhibited the chemiluminescent phagocytic response of leucocytes (cprl) at concentrations comparable with therapeutic ones. ld50/ed50 (cprl inhibition) factor of 3 is offered as the screening threshold for a number of nonsteroidal anti-inflammatory drugs. the possibility of using anticoagulants and anaprilin ... | 1989 | 2663543 |
| purification and characterization of human immunodeficiency virus (hiv) core precursor (p55) expressed in saccharomyces cerevisiae. | the core structure of retroviruses, including the human immunodeficiency virus (hiv), consists of proteins that are initially synthesized as polyprotein precursors and then processed by a virally encoded protease yielding the mature core polypeptides. to obtain sufficient quantities of the purified hiv core precursor p55 for detailed studies, a segment of hiv dna encoding the full length core precursor polyprotein p55 was expressed in saccharomyces cerevisiae using a plasmid containing a constit ... | 1989 | 2663848 |
| [comparative study of the mutagenic activity of dicurin on five test-objects]. | mutagenic activity of dicourol belonging to coumarol derivatives has been studied on 5 test-objects (mice, cultivated lymphocytes of human blood, yeast-saccharomycetes, tradescantia, crepis). results of investigations allowed attributing dicourol to highly hazardous mutagens. in this connection it is admitted unadvisable to enforce it into agricultural practice. the tested objects differ in their dicourol mutagenic sensibility as follows: cultivated lymphocytes of human blood - tradescantia - ye ... | 1989 | 2665249 |
| yeast as source of oncoproteins. | the properties of a saccharomyces cerevisiae 20 kda polypeptide (yp20) and its relationship to human ras antigen were tested. yp20 was isolated from commercial yeast cells by the procedure of sommer (1978). proteins associated with yeast chromatin were released by micrococcal nuclease digestion and purified by sucrose gradient centrifugation. rabbit polyclonal and mouse monoclonal antibodies specifically detecting the yp20 antigen have been generated. we observed that yp20 was recognized by anti ... | 1989 | 2665375 |
| structural and functional properties of ras proteins. | the ras proteins belong to a family of related polypeptides that are present in all eukaryotic organisms from yeast to human. their extraordinary evolutionary conservation suggests that they have essential cellular functions, although their exact role remains unknown. mutations in specific amino acids and overexpression of normal proteins have been linked to altered proliferation and/or differentiation and, particularly, to neoplastic processes. mature ras proteins are located on the inner side ... | 1989 | 2666231 |
| competitive elisa for detection of native ras gene-related products in sera of cancer patients. | a solid phase, enzyme-linked immunosorbent assay (elisa) competition kit was developed to detect circulating native ras gene-related products in sera of 151 healthy volunteers and cancer patients. this assay uses monoclonal antibody (mab) bst-6a generated against a yeast-derived, native ras-related polypeptide yp20. only 2% (1 of 58) of normal control sera showed strong competition, as compared to 15% (5 of 34) of patients with early stage or no evidence of disease, and 44% (26 of 59) of patient ... | 1989 | 2668475 |
| high levels of circulating neutralizing antibody in normal animals to recombinant mouse interferon-beta produced in yeast. | plasma from normal outbred swiss mice not previously given interferon (ifn) neutralized a glycosylated (high-mannose) recombinant murine ifn-beta made in yeast (rmuifn-beta y). the neutralization antibody titers were as high as 1:6,000 versus rmuifn-beta y, whereas the titers obtained with native murine ifn-beta (muifn-beta) were 100-fold less; a recombinant murine ifn-beta make in escherichia coli (rmuifn-beta ec) was not neutralized at 1:10 dilution of plasma. an elisa using rmuifn-beta y demo ... | 1989 | 2809279 |
| rapid screening of a human genomic library in yeast artificial chromosomes for single-copy sequences. | a yeast artificial chromosome (yac) library in saccharomyces cerevisiae consisting of 30,000 clones with an average insert size of 0.1 megabase pair of human dna has been generated from primary fibroblast dna. a yac vector was modified to enable the recovery of both ends of a human dna insert in plasmids in escherichia coli and to confer g418 resistance to mammalian cells. a rapid method for yeast colony hybridization was used that exploits the ability of yeast spheroplasts to regenerate in a th ... | 1989 | 2668948 |
| cloning human telomeric dna fragments into saccharomyces cerevisiae using a yeast-artificial-chromosome vector. | telomeric fragments of human dna ranging in size from 50 to 250 kilobases were cloned into saccharomyces cerevisiae using a yeast-artificial-chromosome (yac) vector. six human-telomeric yac (hty) strains were selected by virtue of the specific hybridization of their dna with the human telomeric terminal-repeat sequence (ttaggg)n, and the telomeric localization of this sequence within each yac was demonstrated by its sensitivity to nuclease bal-31. in situ hybridization of dna from three of these ... | 1989 | 2668959 |
| expression and accurate processing of yeast penta-ubiquitin in escherichia coli. | an expression vector (psjyub-5) was constructed which contained five repeats of the "yeast ubiquitin gene" regulated by a heat-inducible lambda pl promoter. the vector, when expressed in escherichia coli, produced a penta-ubiquitin of approximately 42 kda. purified penta-ubiquitin was found to be as active as the human mono-ubiquitin in the in vitro atp/ubiquitin-dependent proteolytic assay of the reticulocyte lysate, indicating that the expressed gene product was recognized by the enzymes invol ... | 1987 | 2826431 |
| synthesis, processing and degradation in yeast of precursor human lysozyme with newly designed signal sequences. | recently, we reported that the synthesis of human lysozyme in yeast is inhibited when artificially designed non-native signal sequences are used [yamamoto et al. (1987) biochem. biophys. res. commun. 149, 431-436; (1989) biochemistry 28, 2728-2732]. pulse/chase experiments described in the present paper have now revealed that precursor lysozymes are actually synthesized with these signal sequences, but that they are spontaneously degraded, suggesting that the enzyme is destabilized by the signal ... | 1989 | 2673785 |
| secretion of glycosylated human erythropoietin from yeast directed by the alpha-factor leader region. | the pre-pro alpha-factor leader region of the yeast mf alpha 1 gene was used to direct the secretion of the human glycoprotein, erythropoietin (epo), into the culture medium. an examination of the role of expression level on secretion of biologically active epo indicated that there are several rate-limiting steps. these include processing of the alpha-factor-epo precursor protein by the kex2-encoded endoproteinase and transport of the protein through the secretory pathway. the rate-limiting step ... | 1989 | 2673934 |
| human liver serine dehydratase. cdna cloning and sequence homology with hydroxyamino acid dehydratases from other sources. | rat liver serine dehydratase cdna was used to screen a human liver cdna library in lambda gt11. one positive clone occurred in every 5,000 clones. fifteen positive clones were plaque purified. the largest cdna obtained contained an open reading frame of 987 base pairs, and 5' and 3' noncoding regions of 89 and 317 base pairs, respectively. the deduced amino acid sequence, with a calculated mr of 34,615, was similar to that of rat liver serine dehydratase except for the absence of a segment consi ... | 1989 | 2674117 |
| cdna sequence, predicted primary structure, and evolving amphiphilic helix of human aspartyl-trna synthetase. | eight of the mammalian aminoacyl-trna synthetases associate as a multienzyme complex, whereas prokaryotic and low eukaryotic synthetases occur only as free soluble enzymes. association of the synthetases may result in effective compartmentalization of synthetases and suggests the association of the entire protein biosynthetic machinery. to elucidate the structural elements and the nature of the molecular interactions involved in the association of the synthetases, we have cloned and sequenced th ... | 1989 | 2674137 |
| isolation of recombinant hirudin by preparative high-performance liquid chromatography. | the purification of recombinant hirudin variant 2-lys47 (rhv2-lys47), produced by a genetically engineered yeast strain, is described. rhv2-lys47 expressed and secreted into the culture medium was the starting material for the purification process of hirudin from the culture broth after cell harvesting by centrifugation. initial purification of the product by preparative reversed-phase high-performance liquid chromatography (hplc) using step-gradient elution, followed by precipitation of rhv2-ly ... | 1989 | 2674177 |
| adansonian study of candida albicans: intraspecific homogeneity excepting c. stellatoidea strains. | fifty-six strains of candida albicans (40 fresh human isolates, 10 laboratory strains, and 6 candida stellatoidea strains), seven strains of other candida species, and one strain of saccharomyces cerevisiae were examined for a total of 182 biochemical and physiological characters. as 121 characters proved positive or negative in all of the strains, analysis of similarity values (simple matching coefficients) derived from the remaining 61 characters revealed that c. albicans strains could be disc ... | 1989 | 2677300 |
| use of yeast artificial chromosome clones for mapping and walking within human chromosome segment 18q21.3. | well-characterized large genomic clones obtained from yeast artificial chromosome (yac) libraries provide the framework to localize genes and approach genetic disease. we developed universally applicable approaches to establish authenticity, localize and orient internal genes, map restriction sites, and rescue the distal ends of large human genomic dna inserts. we selected human chromosome segment 18q21.3 as a model system. molecular cloning of this segment was initiated by characterizing three ... | 1989 | 2678105 |
| genetic analysis of mammalian gap expressed in yeast. | we have designed a vector to express the mammalian gap protein in the yeast s. cerevisiae. when expressed in yeast, gap inhibits the function of the human h-rasgly12 protein, but not that of the h-rasval12 protein, and complements the loss of ira1. ira1 is a yeast gene that encodes a protein with homology to gap and acts upstream of ras. mammalian gap can therefore function in yeast and interact with yeast ras. because expression of gap complements ira1-mutants, we propose that gap shares some b ... | 1989 | 2684416 |
| perturbation of beta-glucan receptors on human neutrophils initiates phagocytosis and leukotriene b4 production. | normal human neutrophils were stimulated with the yeast cell wall product, zymosan, and examined for two biologic responses, ingestion of particles and production of leukotriene b4 (ltb4), under conditions that were comparable and optimal for the quantitation of each response. monolayers of adherent neutrophils ingested unopsonized zymosan particles, at particle-to-cell ratios of 12.5:1 to 125:1, in a dose- and time-related manner. at a ratio of 125:1, the percentages of neutrophils ingesting gr ... | 1988 | 2844908 |
| the conformation of mature human alpha-amylase conditions its secretion from yeast. | the yeast saccharomyces cerevisiae expresses the cloned cdna (amy) encoding human salivary alpha-amylase (amy) under control of the yeast pho5 promoter, and secretes the active enzyme into the culture medium. two approaches were utilized to define the moiety of amy, which is required for proper secretion and glycosylation. in one approach, chimeras were constructed with a variety of secretion signal sequences (yeast mating factor precursor sequence, yeast acid phosphatase signal sequence and hum ... | 1989 | 2684791 |
| summary of complementation groups of uv-sensitive cho cell mutants isolated by large-scale screening. | a summary is given for the lineage and complementation group assignments of 153 uv-sensitive mutants of the cho aa8 cell line. the distribution of mutants among six complementation groups was highly non-random, with the great majority of the isolates belonging to groups 1 and 2. this asymmetry is consistent with the known hemizygosity of these two linked loci in cho cells. the relative numbers of mutants induced in group 2 was found to depend greatly on the type of mutagen used. mutagenesis with ... | 1989 | 2687628 |
| centromere structure and function in neoplasia. | the mammalian centromere plays an essential role in maintenance of diploidy in the cell. it is therefore imperative that we understand the structure and function of the mammalian centromere in order to plan strategy to control the incidence of aneuploidy and resultant malformations of the nonneoplastic as well as neoplastic tissues. even though considerable information is available about the structure and some functional aspects of centromeres of lower eukaryotes such as yeast, the structure of ... | 1989 | 2688870 |
| potent antagonism of escherichia coli, bacteroides ovatus, fusobacterium varium, and enterococcus faecalis, alone or in combination, for enteropathogens in anaerobic continuous flow cultures. | interactions between representative strains of four predominant resident bacteria of the human colon, escherichia coli, enterococcus faecalis, bacteroides ovatus, and fusobacterium varium, and strains of seven enteropathogens, yersinia enterocolitica, shigella flexneri, salmonella typhimurium, vibrio parahaemolyticus, v. cholerae serogroup non o1, staphylococcus aureus, and clostridium perfringens, were examined in studies with an anaerobic continuous flow culture system and medium resembling th ... | 1986 | 2875188 |
| the maltose permease encoded by the mal61 gene of saccharomyces cerevisiae exhibits both sequence and structural homology to other sugar transporters. | the mal61 gene of saccharomyces cerevisiae encodes maltose permease, a protein required for the transport of maltose across the plasma membrane. here we report the nucleotide sequence of the cloned mal61 gene. a single 1842 bp open reading frame is present within this region encoding the 614 residue putative mal61 protein. hydropathy analysis suggests that the secondary structure consists of two blocks of six transmembrane domains separated by an approximately 71 residue intracellular region. th ... | 1989 | 2689282 |
| a highly evolutionarily conserved mitochondrial protein is structurally related to the protein encoded by the escherichia coli groel gene. | we recently reported that a tetrahymena thermophila 58-kilodalton (kda) mitochondrial protein (hsp58) was selectively synthesized during heat shock. in this study, we show that hsp58 displayed antigenic similarity with mitochondrially associated proteins from saccharomyces cerevisiae (64 kda), xenopus laevis (60 kda), zea mays (62 kda), and human cells (59 kda). furthermore, a 58-kda protein from escherichia coli also exhibited antigenic cross-reactivity to an antiserum directed against the t. t ... | 1988 | 2892128 |
| mammalian cyclin/pcna (dna polymerase delta auxiliary protein) stimulates processive dna synthesis by yeast dna polymerase iii. | human cyclin/pcna (proliferating cell nuclear antigen) is structurally, functionally, and immunologically homologous to the calf thymus auxiliary protein for dna polymerase delta. this auxiliary protein has been investigated as a stimulatory factor for the nuclear dna polymerases from s. cerevisiae. calf cyclin/pcna enhances by more than ten-fold the ability of dna polymerase iii to replicate templates with high template/primer ratios, e.g. poly(da).oligo(dt) (40:1). the degree of stimulation in ... | 1988 | 2899883 |
| actions of three human alpha-amylases expressed in yeast on modified substrates and the amino acid residues causing their different actions. | the mode of action of an alpha-amylase (yhxa) which was the gene product of a newly found human alpha-amylase gene expressed in yeast on synthetic substrates was compared with those of the gene products (yhsa and yhpa) of human salivary and pancreatic alpha-amylase gene in yeast. the substrates used were phenyl alpha-maltopentaoside (g5 phi) and its derivatives in which the ch2oh groups of the non-reducing-end glucose residues were converted to ch2nh2 (ag5 phi), cooh (cg5 phi), or ch2i (ig5 phi) ... | 1989 | 2691509 |
| use of zetaprep cartridge for the purification of human recombinant interleukin 1 beta. | zetaprep mass ion-exchange media represent a rapid and efficient chromatographic tool in the separation of proteins, in place of the conventional agarose or cellulose-based gels. we adopted this method, combined with classical steps, to purify to homogeneity human recombinant interleukin 1 beta (il-1 beta) produced from e. coli and from s. cerevisiae. an anion exchanger qae-zetaprep was used to achieve a rapid partial purification of both proteins. the il-1 beta purification was completed by gel ... | 1989 | 2662172 |
| mouse primase p49 subunit molecular cloning indicates conserved and divergent regions. | primase is a specialized rna polymerase that synthesizes rna primers for initiation of dna synthesis. a full cdna clone of the p49 subunit of mouse primase, a heterodimeric enzyme, has been isolated using a primase p49-specific polyclonal antibody to screen a lambda gt11 mouse cdna expression library. the cdna indicated the subunit is a 417-amino acid polypeptide with a calculated molecular mass of 49,295 daltons. the p49 mrna is approximately 1500 nucleotides long with a 5'-untranslated region ... | 1989 | 2925677 |
| uncoating atpase is a member of the 70 kilodalton family of stress proteins. | the synthetic peptide, vgidlgttysc, derived from the heat shock-induced genes human hsp70, drosophila hsp70, s. cerevisiae yg100, and e. coli dnak, elicited antibodies that recognized two constitutive proteins in bovine extracts. one of these proteins, 71 kd, has previously been identified as uncoating atpase, an enzyme that releases clathrin from coated vesicles. this immunological data complemented the result that uncoating atpase was indistinguishable from the constitutive mammalian 71 kd str ... | 1986 | 2937542 |