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a polyprotein precursor of two mitochondrial enzymes in neurospora crassa. gene structure and precursor processing.n-acetylglutamate kinase (agk) and n-acetyl-gamma-glutamyl-phosphate reductase (agpr) function as two separate mitochondrial enzymes, but are encoded by a single nuclear gene in several fungi. the neurospora crassa arg-6 gene encoding these enzymes has been cloned and sequenced, and the enzymes responsible for processing the polyprotein precursor have been identified. the 871-amino acid precursor contains a normal n-terminal mitochondrial targeting sequence, an internal connecting region (approx ...19947907589
at least three genes are responsible for benomyl-resistance in metarhizium anisopliae.four benomyl-resistant mutants isolated from metarhizium anisopliae were 10 to 500 times more resistant than the original mt strain. the resistance markers analysed in three of these mutants were due to three different mutations and no additive effect of these genes was observed in double mutants. the four mutants presented normal conidiation in the presence or absence of benomyl and no sensitivity or resistance to temperature. probably m. anisopliae has a mechanism of benomyl resistance differi ...19948127229
molybdenum(vi) salts convert the xanthine oxidoreductase apoprotein into the active enzyme in mouse l929 fibroblastic cells.the mouse l929 fibroblastic cell line presents low, but detectable, levels of the mrna encoding xanthine oxidoreductase under basal conditions, and it responds to type i and type ii interferons by inducing the expression of the transcript [falciani, ghezzi, terao, cazzaniga, and garattini (1992) biochem. j. 285, 1001-1008]. this cell line, however, does not show any detectable amount of xanthine oxidoreductase enzymic activity, either before or after treatment with the cytokines. molybdenum(vi) ...19948129733
3-carboxy-cis,cis-muconate lactonizing enzyme from neurospora crassa: an alternate cycloisomerase motif.3-carboxy-cis,cis-muconate lactonizing enzyme (cmle; ec 5.5.1.5) from neurospora crassa catalyzes the reversible gamma-lactonization of 3-carboxy-cis,cis-muconate by a syn-1,2 addition-elimination reaction. the stereochemical and regiochemical course of the reaction is (i) opposite that of cmle from pseudomonas putida (ec 5.5.1.2) and (ii) identical to that of cis,cis-muconate lactonizing enzyme (mle; ec 5.5.1.1) from p. putida. in order to determine the mechanistic and evolutionary relationship ...19948132467
similarities between a soybean nodulin, neurospora crassa sulphate permease ii and a putative human tumour suppressor. 19948140616
the search for the right partner: homologous pairing and dna strand exchange proteins in eukaryotes.finding the right partner is a central problem in homologous recombination. common to all models for general recombination is a homologous pairing and dna strand exchange step. in prokaryotes this process has mainly been studied with the reca protein of escherichia coli. two approaches have been used to find homologous pairing and dna strand exchange proteins in eukaryotes. a biochemical approach has resulted in numerous proteins from various organisms. almost all of these proteins are biochemic ...19948143796
homologs of the yeast neck filament associated genes: isolation and sequence analysis of candida albicans cdc3 and cdc10.morphogenesis in the yeast saccharomyces cerevisiae consists primarily of bud formation. certain cell division cycle (cdc) genes, cdc3, cdc10, cdc11, cdc12, are known to be involved in events critical to the pattern of bud growth and the completion of cytokinesis. their products are associated with the formation of a ring of neck filaments that forms at the region of the mother cell-bud junction during mitosis. morphogenesis in candida albicans, a major fungal pathogen of humans, consists of bot ...19948152419
cloning and characterisation of the cytochrome c gene of aspergillus nidulans.the cytochrome c gene (cyca) of the filamentous fungus aspergillus nidulans has been isolated and sequenced. the gene is present in a single copy per haploid genome and encodes a polypeptide of 112 amino acid residues. the nucleotide sequence of the a. nidulans cyca gene shows 87% identity to the dna sequence of the neurospora crassa cytochrome c gene, and approximately 72% identity to the sequence of the saccharomyces cerevisiae iso-1-cytochrome c gene (cyc1). the s. cerevisiae cyc1 gene was us ...19948277943
specific recognition of mitochondrial preproteins by the cytosolic domain of the import receptor mom72.the import receptor mom72 constitutes part of the protein translocation machinery of the outer mitochondrial membrane, the receptor-general insertion pore complex. the protein contains a membrane anchor at the nh2 terminus and a large cytosolic domain. in yeast and neurospora crassa the cytosolic domain comprises about 570-580 amino acid residues. the cytosolic domain of yeast mom72 was purified after expression in escherichia coli as a homogeneous monomeric protein. it can recognize precursor p ...19948163488
in organello assembly of respiratory-chain complex i: primary structure of the 14.8 kda subunit of neurospora crassa complex i.a cdna encoding the 14.8 kda subunit of complex i from neurospora crassa was cloned and sequenced. the deduced primary structure of this subunit reveals a predominantly hydrophilic protein containing no obvious membrane-spanning domain. in agreement with this characteristic, we have localized the 14.8 kda subunit in the peripheral arm of the enzyme. the 14.8 kda subunit was found to be conserved in mammalian complex i. the conservation of this subunit in such distantly related organisms suggests ...19948166654
characterization of a 3-dehydroquinase gene from actinobacillus pleuropneumoniae with homology to the eukaryotic genes qa-2 and qute.a gene was cloned from actinobacillus pleuropneumoniae strain 4074 by complementation of an arod strain of escherichia coli. the e. coli gene arod codes for a 3-dehydroquinase enzyme of type i, active in the aromatic biosynthesis pathway. the a. pleuropneumoniae gene, termed aroq, displays no base or amino acid sequence homology to arod of e. coli. it is instead homologous to the qute and qa-2 genes, respectively of aspergillus nidulans and neurospora crassa. these genes code for 3-dehydroquinas ...19948170389
on the structure of mitochondrial porins and its homologies with bacterial porins.by use of computer modelling, we have predicted a model of 16 transmembrane beta-strands for mitochondrial porins structure from human, saccharomyces cerevisiae, neurospora crassa and dictyostelium discoideum. the proposed model takes into account biochemical and immunological data reported in the literature, as well as electrophysiological results obtained with yeast mitochondrial porins with mutations at selected amino acids. the predicted structure is very similar to that of some bacterial po ...19948179626
genetic risk assessment and specific-locus mutations in the ad-3 region of neurospora crassa.data from experiments on the induction of specific-locus mutations in model systems are used in genetic risk assessment to estimate potential adverse effects in the human population. in such assessments with radiation or chemical mutagens, the following information is required: a) spontaneous and induced forward-mutation frequencies, b) dose-response curves for the overall induction of specific-locus mutations, c) genetic characterization of spontaneous and induced mutations, and d) dose-respons ...19948187730
intergeneric complementation of a circadian rhythmicity defect: phylogenetic conservation of structure and function of the clock gene frequency.the neurospora crassa frequency locus encodes a 989 amino acid protein that is a central component, a state variable, of the circadian biological clock. we have determined the sequence of all or part of this protein and surrounding regulatory regions from additional fungi representing three genera and report that there is distinct, preferential conservation of the frequency open reading frame (orf) as compared with non-coding sequences. within the coding region, many of the domain hallmarks of t ...19948194516
preproteins of chloroplast envelope inner membrane contain targeting information for receptor-dependent import into fungal mitochondria.the amino-terminal transit sequences of two preproteins destined for the chloroplast inner envelope membrane show similarities to mitochondrial presequences in the prevalence of positive charges and the potential formation of an amphipathic alpha-helix. we studied if these preproteins could be imported into mitochondria and found a low, yet significant import into isolated plant mitochondria. the plant mitochondria were previously shown not to import precursors of chloroplast stromal or thylakoi ...19948206957
characterization of the mitochondrial processing peptidase of neurospora crassa.the mitochondrial processing peptidase (mpp) of neurospora crassa is constituted by an alpha- and a beta-subunit. we have purified alpha-mpp after expression in escherichia coli while beta-mpp was purified from mitochondria. a fusion protein between precytochrome b2 and mouse dihydrofolate reductase was expressed in e. coli, and the purified protein was used as substrate for mpp. both subunits of mpp are required for processing. mpp removes the matrix targeting signal of cytochrome b2 by a singl ...19948106471
cis,cis-muconate lactonizing enzyme from trichosporon cutaneum: evidence for a novel class of cycloisomerases in eucaryotes.the absolute stereochemical courses of cis,cis-muconate lactonizing enzyme (mle;ec 5.5.1.1) from trichosporon cutaneum (tcmle) and chloromuconate cycloisomerase (mle ii; ec 5.5.1.7) from pseudomonas sp b13 have been determined from 1h nmr measurements. both cycloisomerases convert cis,cis-muconate to (4s)-muconolactone by a syn lactonization, the absolute stereochemical outcome of which is identical to that observed with mle from pseudomonas putida. the regiochemical courses of cyclization of 3- ...19948110801
small lipid-soluble cations are not membrane voltage probes for neurospora or saccharomyces.small lipid-soluble cations, such as tetraphenylphosphonium (tpp+) and tetraphenylarsonium (tpa+) are frequently used as probes of membrane voltage (delta psi, or vm) for small animal cells, organelles, and vesicles. because much controversy has accompanied corresponding measurements on 'walled' eukaryotic cells (plants, fungi), we studied their transport and relation to vm in the large-celled fungus neurospora crassa-where vm can readily be determined with microelectrodes-as well as in the most ...19948110820
a novel carotenoid biosynthesis gene coding for zeta-carotene desaturase: functional expression, sequence and phylogenetic origin.a dna fragment which has been isolated previously from an anabaena dna expression library was subcloned. the corresponding protein was overexpressed in escherichia coli. the recombinant enzyme was fully active in converting zeta-carotene into lycopene in vitro with neurosporene as an intermediate. a smaller fragment which still contained the active enzyme was sequenced. an open reading frame of 1497 bp was found coding for a protein consisting of 499 amino acids with the calculated molecular wei ...19948111038
disruption of the gene encoding the nadh-binding subunit of nadh: ubiquinone oxidoreductase in neurospora crassa. formation of a partially assembled enzyme without fmn and the iron-sulphur cluster n-3.in this study, the gene of the 51-kda nadh-binding subunit of the mitochondrial nadh:ubiquinone oxidoreductase (complex i) in neurospora crassa was inactivated by homologous replacement with a defective gene copy. the resulting mutant, nuo51, lacks the 51-kda subunit and shows no complex i activity but still grows at one third of the wild-type growth rate. the enzyme activity of the alternative nadh:ubiquinone oxidoreductase(s) is increased twofold while the activities of the other mitochondrial ...19948125114
two nuclear-coded subunits of mitochondrial complex i are similar to different domains of a bacterial formate hydrogenlyase subunit.a computer comparison of protein sequences revealed similarity between the 30.4 kda subunit of complex i from the fungus neurospora crassa and the orf5 subunit of formate hydrogenlyase from escherichia coli. the orf5 protein was previously known to be homologous to the 49 kda component of the mitochondrial enzyme. we show that the 30.4 kda corresponds to the n-terminal part while the 49 kda subunit corresponds to the c-terminal portion of the bacterial protein. thus, this bacterial protein repre ...19947890119
dna binding site specificity of the neurospora global nitrogen regulatory protein nit2: analysis with mutated binding sites.nit2, a positive-acting regulatory protein in neurospora crassa, activates the expression of a series of unlinked structural genes that encode nitrogen catabolic enzymes. nit2 binding sites in the promoter regions of nit3, alc and lao have at least two gata sequence elements. we have examined the binding affinity of the nit2 protein for the yeast dal5 wild-type upstream activation sequence uasntr, which contains two gata elements, and for a series of mutated binding sites, each differing from th ...19947808401
the saccharomyces cerevisiae homologue of ribosomal protein s26.the nucleotide sequence of rps26, the gene encoding a homologue of ribosomal protein small subunit s26 in saccharomyces cerevisiae, was determined. the deduced amino-acid sequence showed significant identity with its counterparts from neurospora crassa, human, rat and arabidopsis thaliana. disruption of rps26 resulted in the formation of micro-colonies, suggesting that it is important for the normal cell growth of s. cerevisiae.19947821815
characterization and expression of an antifungal zeamatin-like protein (zlp) gene from zea mays.a cdna clone encoding a basic thaumatin-like protein of zea mays was recovered from a mid-development seed cdna library. the gene, zlp, encoded a protein that was nearly identical with maize zeamatin and alpha-amylase/trypsin inhibitor. expression of zlp mrna was highest in the endosperm tissue of seed 4 weeks after pollination. expression of zeamatin-like (zlp) protein correlated with mrna; also, a low basal level of zlp expression in leaf was not appreciably induced by abiotic stresses. zlp wa ...19947846159
nitrogen regulation in fungi.nitrogen regulation has been extensively studied in fungi revealing a complex array of interacting regulatory genes. the general characterisation of the systems in aspergillus nidulans and neurospora crassa shall be briefly described, but much of this paper will concentrate specifically on the recent molecular characterisation of area, the principle regulatory gene from a. nidulans which mediates nitrogen metabolite repression. three areas shall be explored in detail, firstly the dna binding dom ...19947847882
reconstitution of import-competent outer membrane vesicles from mammalian mitochondria.protein insertion into mitochondrial outer membrane (om) vesicles isolated from neurospora crassa has recently been reported. the n. crassa om vesicles retained the features of the intact mitochondria concerning the dependency of insertion on the receptor protein [a. mayer et al. (1993) j. cell biol. 121, 1233-1243]. in this study, om vesicles were purified from bovine adrenal cortex mitochondria, and unilamellar proteoliposomes were reconstituted from om vesicles using heptyl beta-thioglucoside ...19947798173
the function and specificity of the c-terminal tripeptide glyoxysomal targeting signal in neurospora crassa.the function of the c-terminal tripeptide targeting signal responsible for microbody targeting in many eukaryotes has been investigated in the filamentous fungus neurospora crassa. using an in-vivo targeting assay that employs transformants carrying c-terminally-modified versions of the bacterial enzyme chloramphenicol acetyltransferase (cat), it has been demonstrated that c-terminal tripeptide-dependent import occurs most efficiently in response to nutritional acetate-induction. under these con ...19947874736
disruption of the cyclosporin synthetase gene of tolypocladium niveum.cyclosporin a is a potent and clinically-important immunosuppressive drug (sandimmunr). it is produced by the fungus tolypocladium niveum. a transformation system for t. niveum atcc34921 based on hygromycin selection was established. in order to obtain a t. niveum promoter, the cyclophilin gene was isolated using the neurospora crassa gene as probe. a plasmid vector was constructed in which the promoter region of the t. niveum cyclophilin gene was fused to a bacterial hygromycin phosphotransfera ...19947874740
dna uptake stimulating protein from neurospora crassa enhances dna and oligonucleotide uptake also in mammalian cells.the presence of the dna uptake stimulating protein (designated earlier as dusf by schablik and szabó (1981) fems microbiol. lett. 10, 395-397) was demonstrated on the surface of neurospora crassa (fgsc 1118, slime) fungal cells as well as on hep-2 and k562 human and f4n mouse tumor cells by immunofluorescence microscopy. dusf markedly enhanced the uptake of both macromolecular [3h]dna and of [3h]oligonucleotides by k562, hl-60 and also by dd human leukemia cells. polyclonal anti-dusf antibodies ...19947918627
isolation and characterization of cdna and genomic promoter region for a heat shock protein 30 from aspergillus nidulans.a cdna encoding for a heat shock protein 30 (hsp30) of aspergillus nidulans and the promoter region of its gene were analyzed for their primary structures. the promoter region had no heat shock element but possessed three inverted repeat sequences. northern blot hybridization indicated that the expression of the hsp30 gene was high at a normal temperature and was slightly accelerated at elevated temperatures in a. nidulans cells. although the deduced amino acid sequence of the a. nidulans hsp30 ...19947918658
mitochondrial grpe is present in a complex with hsp70 and preproteins in transit across membranes.we characterized a 24-kda protein associated with matrix hsp70 (mt-hsp70) of neurospora crassa and saccharomyces cerevisiae mitochondria. by using specific antibodies, the protein was identified as mge, a mitochondrial homolog of the prokaryotic heat shock protein grpe. mge extracted from mitochondria was quantitatively bound to hsp70. it was efficiently released from hsp70 by the addition of mg-atp but not by nonhydrolyzable atp analogs or high salt. a mutant mt-hsp70, which was impaired in rel ...19947935381
cloning and characterization of a neurospora crassa gene required for (1,3) beta-glucan synthase activity and cell wall formation.the glucan synthase 1 gene (gs-1) is required for (1,3) beta-glucan synthase activity [e.c. 2.4.1.34; udp glucose:1,3-beta-d-glucan 3-beta-d-glucosyltransferase] and for cell wall formation. the gs-1 gene was cloned by functional complementation of the cell-wall-less defect of the (1,3) beta-glucan synthase-deficient mutant, tm1, by using a genomic neurospora crassa cosmid library. a 2568-nucleotide gs-1 cdna sequence revealed a 532-amino acid open reading frame encoding a polypeptide of 59 kda. ...19947937796
dna photolyase from the fungus neurospora crassa. purification, characterization and comparison with other photolyases.a phr-gene from the filamentous fungus neurospora crassa was overexpressed in escherichia coli cells, yielding a biologically active photolyase. after purification till apparent homogeneity, the 66 kda protein was found to contain equimolar amounts of 5,10-methenyltetrahydrofolic acid (mthf) and fad, classifying it as an mthf-type photolyase. compared to other mthf photolyases the absorption maximum of neurospora photolyase is shifted from ca 380 nm to 391 nm (epsilon = 34,800), while an additio ...19947938208
nadh: ubiquinone oxidoreductase in obligate aerobic yeasts.the strictly aerobic yeasts candida pinus, cryptococcus albidus, rhodotorula minuta, rhodotorula mucilaginosa and trichosporon beigelii possess mitochondrial nadh dehydrogenases with significant features of the nadh:ubiquinone oxidoreductase (complex i). these species show in all growth phases and under standard cultivation conditions, nadh dehydrogenases of approximately 700 kda, which are sensitive to rotenone, a specific inhibitor of this complex. identical results were obtained with the weak ...19947941733
characterization of chitin synthase from botrytis cinerea.chitin synthase in a microsomal preparation from botrytis cinerea had an apparent km for udp-n-acetylglucosamine of 2.0 mm while nikkomycin z and polyoxin d inhibited enzyme activity competitively with apparent ki values of approximately 0.1 microm and 6 microm respectively. the organophosphorus fungicide edifenphos was a non-competitive inhibitor (ki(app) 54 microm). preincubation of microsomes for 2 h at 25 degrees c resulted in a maximum twofold stimulation of chitin synthase activity while p ...19947952170
a cosmid with a hyr marker for fungal library construction and screening.the construction of a double-cos-site cosmid vector, pmocosx, for use in making filamentous fungal genomic dna libraries, is described. the vector has features that allow for selection of clones introduced into fungi by transformation and for efficient chromosome walking experiments. these features include (i) two cos sites allowing for easy construction of libraries without requiring size selection of insert dna; (ii) an xhoi site for insertion of sau3ai or mboi partially digested genomic dna i ...19947959044
pulsed growth of fungal hyphal tips.somatic fungal hyphae are generally assumed to elongate at steady linear rates when grown under constant environmental conditions with ample nutrients. however, patterns of pulsed hyphal elongation were detected during apparent steady growth of hyphal tips in fungi from several major taxonomic groups (oomycetes, pythium aphanidermatum and saprolegnia ferax; zygomycetes, gilbertella persicaria; deuteromycetes, trichoderma viride; ascomycetes, neurospora crassa and fusarium culmorum; basidiomycete ...19947991610
interaction of phlorizin, a potent inhibitor of the na+/d-glucose cotransporter, with the nadph-binding site of mammalian catalases.phlorizin is a reversible inhibitor of the renal and small intestinal na+/d-glucose cotransporter. in an attempt to purify the na+/d-glucose cotransporter from a pig kidney brush border membrane fraction, we used an affi-gel affinity chromatography column to which 3-aminophlorizin had been coupled. a protein, composed according to crosslinking experiments of at least 3 subunits of molecular weight 60 kda, was found to bind specifically to the phlorizin column. this protein was subsequently ident ...19948003987
the characterization of a mitochondrial acyl carrier protein isoform isolated from arabidopsis thaliana.a cdna clone was isolated from an arabidopsis leaf cdna library that shared a high degree of protein sequence identity with mitochondrial acyl carrier proteins (mtacps) isolated from neurospora crassa and bovine heart muscle. the cdna encoded an 88-amino acid mature protein that was preceded by a putative 35-amino acid presequence. in vitro protein import studies have confirmed that the presequence specifically targets this protein into pea mitochondria but not into chloroplasts. these studies i ...19948016262
high yield expression of the neurospora crassa plasma membrane h(+)-atpase in saccharomyces cerevisiae.a simple system for high yield expression of the neurospora plasma membrane h(+)-atpase is described. two neurospora h(+)-atpase cdnas differing only in a few bases preceding the coding region were cloned into a high copy number yeast expression vector under the control of the constitutive promoter of the yeast plasma membrane h(+)-atpase, and the resulting plasmids were used to transform saccharomyces cerevisiae strain rs-72, which requires a plasmid-borne functional plasma membrane h(+)-atpase ...19948021283
atp synthase of yeast mitochondria. isolation of the f1 delta subunit, sequence and disruption of the structural gene.the delta-subunit was isolated from the purified yeast f1. partial protein sequences were determined by direct methods. from this information, degenerated primers were constructed. a part of the atp delta gene was amplified by polymerase chain reaction from yeast genomic dna. from the amplified dna sequence, a nondegenerated oligonucleotide probe was constructed to isolate a 2.6-kbp bamhi-ecori dna fragment bearing the whole gene. a 1036-bp drai fragment was sequenced. a 480-bp open reading fram ...19948026496
efficient independent activity of a monomeric, monofunctional dehydroquinate synthase derived from the n-terminus of the pentafunctional arom protein of aspergillus nidulans.the dehydroquinate synthase (dhq synthase) functional domain from the pentafunctional arom protein of aspergillus nidulans has previously been overproduced in escherichia coli [van den hombergh, moore, charles and hawkins (1992) biochem j. 284, 861-867]. we now report the purification of this domain to homogeneity and subsequent characterization. the monofunctional dhq synthase was found to retain efficient catalytic activity when compared with the intact pentafunctional arom protein of neurospo ...19948037684
cell-surface receptors for gibbon ape leukemia virus and amphotropic murine retrovirus are inducible sodium-dependent phosphate symporters.cell surface receptors for gibbon ape leukemia virus (glvr-1) and murine amphotropic retrovirus (ram-1) are distinct but related proteins having multiple membrane-spanning regions. distant homology with a putative phosphate permease of neurospora crassa suggested that these receptors might serve transport functions. by expression in xenopus laevis oocytes and in mammalian cells, we have identified glvr-1 and ram-1 as sodium-dependent phosphate symporters. two-electrode voltage-clamp analysis ind ...19948041748
cloning and characterization of the pepe gene of aspergillus niger encoding a new aspartic protease and regulation of pepe and pepc.we have cloned the pepe gene of aspergillus niger, encoding an aspartic protease (pepe), by screening a lambda genomic dna library with a heterologous probe, the neurospora crassa gene coding for a vacuolar proteinase. sequencing of pepe genomic and cdna clones revealed that the gene contains three introns, which are 91, 56 and 58-bp long. the deduced protein consists of 398 amino acids, has a putative signal sequence to allow transport into the endoplasmic reticulum and probably undergoes a sec ...19948056328
isolation, sequence, and characterization of the cercospora nicotianae phytoene dehydrogenase gene.we have cloned and sequenced the cercospora nicotianae gene for the carotenoid biosynthetic enzyme phytoene dehydrogenase. analysis of the derived amino acid sequence revealed it has greater than 50% identity with its counterpart in neurospora crassa and approximately 30% identity with prokaryotic phytoene dehydrogenases and is related, but more distantly, to phytoene dehydrogenases from plants and cyanobacteria. our analysis confirms that phytoene dehydrogenase proteins fall into two groups: th ...19948085820
functional analyses of the neurospora crassa mt a-1 mating type polypeptide.the neurospora crassa mt a-1 gene, encoding the mt a-1 polypeptide, determines a mating type properties: sexual compatibility and vegetative incompatibility with a mating type. we characterized in vivo and in vitro functions of the mt a-1 polypeptide and specific mutant derivatives. mt a-1 polypeptide produced in escherichia coli bound to specific dna sequences whose core was 5'-ctttg-3'. dna binding was a function of the mt a-1 hmg box domain (a dna binding motif found in high mobility group pr ...19948088517
superoxide dismutase (sod-1) null mutants of neurospora crassa: oxidative stress sensitivity, spontaneous mutation rate and response to mutagens.enzymatic superoxide-dismutase activity is believed to be important in defense against the toxic effects of superoxide. although superoxide dismutases are among the best studied proteins, numerous questions remain concerning the specific biological roles of the various superoxide-dismutase types. in part, this is because the proposed damaging effects of superoxide are manifold, ranging from inactivation of certain metabolic enzymes to dna damage. studies with superoxide-deficient mutants have pr ...19948088518
pcr-based cloning of the full-length neurospora eukaryotic initiation factor 5a cdna: polyhistidine-tagging and overexpression for protein affinity binding.eukaryotic initiation factor 5a (eif-5a) is the only cellular protein known to contain a hypusine residue that is formed by transferring the aminobutyl moiety from spermidine to a specific lysine residue, followed by hydroxylation at the aminobutyl group. a simple pcr-based strategy was developed to obtain a full-length cdna of neurospora crassa eif-5a. the strategy consists of (i) the design of a pair of key primers (21-mer) based on the highly conserved eif-5a cdna domains known in other speci ...19948093005
identification of three chitin synthase genes in the dimorphic fungal pathogen sporothrix schenckii.degenerate pcr primers were used to amplify a 600-bp conserved gene region for chitin synthases from genomic dna of sporothrix schenckii, a dimorphic fungal pathogen of humans and animals. three chitin synthase gene homologs were amplified as shown by dna sequence analysis and by southern blotting experiments. based on differences among the predicted amino acid sequences of these homologs, each was placed within one of three different chitin synthase classes. phylogenies constructed with the seq ...19947765092
purification of arginase from aspergillus nidulans.arginase (ec 3.5.3.1) of aspergillus nidulans, the enzyme which enables the fungus to use arginine as the sole nitrogen source was purified to homogeneity. molecular mass of the purified arginase subunit is 40 kda and is similar to that reported for the neurospora crassa (38.3 kda) and saccharomyces cerevisiae (39 kda) enzymes. the native molecular mass of arginase is 125 kda. the subunit/native molecular mass ratio suggests a trimeric form of the protein. the arginase protein was cleaved and pa ...19947732765
palindromic repeated sequences (prss) in the mitochondrial genome of rice: evidence for their insertion after divergence of the genus oryza from the other gramineae.we have identified a family of small repeated sequences (from 60 to 66 bp in length) in the mitochondrial genome of rice (oryza sativa cv. nipponbare). there are at least ten copies of these sequences and they are distributed throughout the mitochondrial genome. each is potentially capable of forming a stem-and-loop structure and we have designated them prss (palindromic repeated sequences). their features are reminiscent of the small dispersed repeats in the mitochondrial dna (mtdna) of some lo ...19947509206
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. xii. analysis of multiple-locus ad-3 mutations reveals a nonrandom distribution of the separate sites of recessive lethal damage throughout the genome.previous studies on x-ray-induced adenine-3 mutations induced in heterokaryon 12 of neurospora crassa showed that they consisted of gene/point mutations, multilocus deletion mutations, and 3 different genotypic classes of multiple-locus mutations (designated [-3]ir + rlcl, ad-3r + rlcl, and ad-3r + rl). in the present paper, multiple-locus mutations consisting of gene/point mutations at the ad-3a or the ad-3b locus with sites of recessive lethal damage closely linked to the ad-3 region (designat ...19947513795
forward-mutation tests on the antitumor agent icr-170 in neurospora crassa demonstrate that it induces gene/point mutations in the ad-3 region and an exceptionally high frequency of multiple-locus ad-3 mutations with closely linked sites of recessive lethal damage.the mutagenicity of the antitumor agent icr-170 (2-methoxy-6-chloro-9-[(ethyl-2-chloroethyl)amino propylamino] acridine dihydrochloride) in the adenine-3 (ad-3) region was studied with a two-component heterokaryon (h-12) of neurospora crassa. the objective was to characterize the genetic damage produced by this acridine nitrogen mustard derivative to determine in a lower eukaryotic organism the basis for its potent activity against ascites tumors in mice. as in higher eukaryotes, specific-locus ...19947523879
peptide-specific antibodies as probes of the topography of the voltage-gated channel in the mitochondrial outer membrane of neurospora crassa.the voltage-dependent anion-selective channel (vdac) in mitochondrial outer membranes is formed by a polypeptide (m(r) 31,000) coded by a nuclear gene whose cdna sequence is known for several organisms. antibodies have been raised against synthetic peptides corresponding to four different regions in the predicted sequence of the vdac polypeptide of the fungus neurospora crassa (residues 1-20, amino terminus; 195-210, 251-268, and 272-283, carboxyl terminus). specificity of the antibodies has bee ...19957542652
homology cloning of gtp-cyclohydrolase i from various unrelated eukaryotes by reverse-transcription polymerase chain reaction using a general set of degenerate primers.gtp-cyclohydrolase i is the primary enzyme of tetrahydrobiopterin and folic acid biosynthesis. cdna fragments of gtp-cyclohydrolase i were obtained from rainbow trout, chicken, the fungi neurospora crassa, phycomyces blakesleeanus and saccharomyces cerevisiae, the cellular slime mold dictyostelium discoideum, the phytoflagellate euglena gracilis and the higher plant mucuna hassjo using primers specific for conserved regions of the open reading frame and the reverse transcription polymerase chain ...19957542887
phylogenetic ordinal placement based on rdna sequences of the freshwater genera ophioceras and pseudohalonectria.the ordinal placement of two closely related freshwater genera, ophioceras and pseudohalonectria, was assessed by using phylogenetic analysis of morphological characters, partial sequences of the large subunit ribosomal dna and restriction site variations in the internal transcribed spacer (its). the two genera have some morphological features that are used to define taxa in both the sordariales and diaporthales, and, hence, their phylogenetic relationships are unclear. equally weighted analyses ...19957553269
sequence of the met-10+ locus of neurospora crassa: homology to a sequence of unknown function in saccharomyces cerevisiae chromosome 8.we have determined the sequence of the neurospora crassa met-10+ gene and its flanking regions, and have isolated and analyzed cdna clones for this region. we have identified two closely linked genes transcribed in the same orientation. the met-10+ gene is the downstream gene; an open reading frame (orf) derived from five exons encodes a 475-amino-acid protein. the deduced protein lacks similarity to other characterized proteins. however, it exhibits a strong similarity to the product of an orf ...19957557397
escherichia coli chorismate synthase catalyzes the conversion of (6s)-6-fluoro-5-enolpyruvylshikimate-3-phosphate to 6-fluorochorismate. implications for the enzyme mechanism and the antimicrobial action of (6s)-6-fluoroshikimate.chorismate synthase catalyzes the conversion of 5-enolpyruvylshikimate-3-phosphate to chorismate. it is the seventh enzyme of the shikimate pathway, which is responsible for the biosynthesis of aromatic metabolites from glucose. the chorismate synthase reaction involves a 1,4-elimination with unusual anti-stereochemistry and requires a reduced flavin cofactor. the substrate analogue (6s)-6-fluoro-5-enolpyruvylshikimate-3-phosphate is a competitive inhibitor of neurospora crassa chorismate syntha ...19957559411
molecular characterization of the proline-1 (pro-1) locus of neurospora crassa, which encodes delta 1-pyrroline-5-carboxylate reductase.delta 1-pyrroline-5-carboxylate reductase (p5cr; [l-proline: nad(p+) 5-oxidoreductase]; ec 1.5.1.2) catalyzes the final step in proline biosynthesis. we have shown that the proline-1 (pro-1) locus of neurospora crassa encodes p5cr. the pro-1 gene was localized to a 3.2 kb region by complementation of (restoration of proline-independent growth to) a proline auxotroph carrying a recessive mutation at the pro-1 locus. the nucleotide sequence of this 3.2 kb region contains an open reading frame with ...19957565596
translational regulation in response to changes in amino acid availability in neurospora crassa.we examined the regulation of neurospora crassa arg-2 and cpc-1 in response to amino acid availability.arg-2 encodes the small subunit of arginine-specific carbamoyl phosphate synthetase; it is subject to unique negative regulation by arg and is positively regulated in response to limitation for many different amino acids through a mechanism known as cross-pathway control. cpc-1 specifies a transcriptional activator important for crosspathway control. expression of these genes was compared with ...19957565672
immunological evidence for accumulation of two high-molecular-weight (104 and 90 kda) hsps in response to different stresses in rice and in response to high temperature stress in diverse plant genera.rice seedlings accumulate stainable amounts of the 104 and 90 kda polypeptides in response to high temperature stress. we have purified and raised highly specific polyclonal antisera against both of these polypeptides. in western blotting experiments, we find that these proteins are accumulated to different extents in rice seedlings subjected to salinity (nacl), water stress, low-temperature stress and exogenous abscisic acid application. these proteins also accumulated when rice seedlings grown ...19957579180
molecular cloning, sequencing and sequence analysis of the fox-2 gene of neurospora crassa encoding the multifunctional beta-oxidation protein.we present the molecular cloning and sequencing of genomic and cdna clones of the fox-2 gene of neurospora crassa, encoding the multifunctional beta-oxidation protein (mfp). the coding region of the fox-2 gene is interrupted by three introns, one of which appears to be inefficiently spliced out. the encoded protein comprises 894 amino acid residues and exhibits 45% and 47% sequence identity with the mfps of candida tropicalis and saccharomyces cerevisiae, respectively. sequence analysis identifi ...19957715608
yeast phylogenetic relationships based on cytochrome c sequences.the availability of the kicyc1 sequence was used to establish homologies with other cytochrome c genes from yeasts and the fungus neurospora crassa. in terms of nucleotide composition, the cytochrome c gene from kluyveromyces lactis showed a higher homology with schwanniomyces occidentalis than with saccharomyces cerevisiae, and this point is discussed in regard to the differences found in the codon usage of these yeasts. the deduced amino acidic composition of the protein facilitated comparison ...19957731389
analysis of cys3 regulator function in neurospora crassa by modification of leucine zipper dimerization specificity.the cys3 positive regulator is a basic region-leucine zipper (bzip) dna-binding protein that is essential for the expression of sulfur-controlled structural genes in neurospora crassa. an approach of modifying the dimerization specificity of the cys3 leucine zipper was used to determine whether the in vivo regulatory function of cys3 requires the formation of homodimeric or heterodimeric complexes. two altered versions of cys3 with coiled coil elecrostatic interactions favorable to heterodimeriz ...19957731792
repressible cation-phosphate symporters in neurospora crassa.the filamentous fungus neurospora crassa possesses two nonhomologous high-affinity phosphate permeases, pho-4 and pho-5. we have isolated separate null mutants of these permeases, allowing us to study the remaining active transporter in vivo in terms of phosphate uptake and sensitivity to inhibitors. the specificity for the cotransported cation differs for pho-4 and pho-5, suggesting that these permeases employ different mechanisms for phosphate translocation. phosphate uptake by pho-4 is stimul ...19957732001
nucleotide sequence and characterization of the large mitochondrial rrna gene of penicillium urticae, and its comparison with those of other filamentous fungi.the nucleotide sequence of a large rrna gene and its flanking regions in cloned fragments of mitochondrial dna from a patulin producer, penicillium urticae nrrl2159a, was determined by dideoxy sequencing, and the 5' end and intron-exon border of the 1-rrna gene were determined by primer extension analysis and rna sequencing, respectively. in addition to the extensive sequence homology of the 3' end of the p. urticae mt 1-rrna gene with those of aspergillus nidulans and neurospora crassa, the p. ...19957592555
molecular cloning and functional expression of neurospora deoxyhypusine synthase cdna and identification of yeast deoxyhypusine synthase cdna.deoxyhypusine synthase catalyzes the formation of deoxyhypusine residue on the eif-5a precursor using spermidine as the substrate. we have purified deoxyhypusine synthase from neurospora crassa to apparent homogeneity (tao, y., and chen, k. y. (1995) j. biol. chem. 270, 383-386). we have now cloned and characterized the deoxyhypusine synthase cdna using a reverse genetic approach. conceptual translation of the nucleotide sequence of the cloned 1258-base pair cdna revealed an open reading frame c ...19957592594
assembly of the preprotein receptor mom72/mas70 into the protein import complex of the outer membrane of mitochondria.membrane integration and assembly of mom72 from neurospora crassa and its yeast homolog mas70 was studied with isolated mitochondria. after synthesis in vitro, the precursors of mom72/mas70 are tightly folded and expose only their n-terminal amino acid residues comprising the targeting and the membrane anchor domain. insertion of the protein into the mitochondrial outer membrane (mom) occurs in a time- and temperature-dependent manner and is stimulated by atp. mom72/mas70 is then assembled into ...19957592965
the negative-acting nmr regulatory protein of neurospora crassa binds to and inhibits the dna-binding activity of the positive-acting nitrogen regulatory protein nit2.structural genes of the nitrogen regulatory circuit of the filamentous fungus neurospora crassa are under the control of both positive and negative regulatory proteins. nit2, the major positive-acting nitrogen regulatory protein, activates the expression of structural genes within the nitrogen circuit. nit2 binds to upstream activation sites which contain at least two gata core elements in the promoter regions of the nitrogen-controlled structural genes, and activates their transcription, possib ...19957612627
(1,3)-beta-d-glucan synthase activity in mycelial and cell wall-less phenotypes of the fz, sg, os-1 ("slime") mutant strain of neurospora crassa.the cell wall-less fz, sg, os-1 ("slime") triple mutant of neurospora crassa lacks (1,3)-beta-d-glucan synthase activity. fz, sg, os-1 segregants from slime x wild-type crosses initially germinate as a plasmodium (slime-like), but develop hyphae in a few hours and acquire a stable mycelial phenotype (mycelial intermediate). the cell wall-less phenotype (stable slime) can be reisolated from mycelial intermediates by filtration-enrichment selection in medium of high osmolarity. pairs of mycelial i ...19957614368
nuclear dna-binding proteins which recognize the intergenic control region of penicillin biosynthetic genes.the biosynthesis of penicillin, a secondary metabolite produced by penicillium chrysogenum, is subject to sophisticated genetic and metabolic regulation. the structural genes, pcbc and pcbab, which encode two of the penicillin biosynthetic enzymes are separated by a 1.16-kb intergenic region and transcribed divergently from one another. to identify and characterize nuclear proteins which interact with the pcbab-pcbc intergenic promoter region, crude and partially purified nuclear extracts were u ...19957614558
isolation of the vma-4 gene encoding the 26 kda subunit of the neurospora crassa vacuolar atpase.we have isolated the vma-4 gene, which encodes a 25,746 dalton subunit of the vacuolar atpase, from neurospora crassa. the gene contains two introns and was mapped to the left arm of linkage group i. comparison of the predicted amino acid sequence with homologous proteins from saccharomyces cerevisiae, manduca sexta, and bos taurus showed only 25% sequence identity. however, computer-assisted predictions of secondary structures gave similar results for all four proteins. analysis of the sequence ...19957619848
conservative sorting of f0-atpase subunit 9: export from matrix requires delta ph across inner membrane and matrix atp.in an attempt to understand the mechanisms of sorting of mitochondrial inner membrane proteins, we have analyzed the import of subunit 9 of the mitochondrial f1f0-atpase (su9) from neurospora crassa, an integral inner membrane protein. a chimeric protein was used consisting of the presequence and the first transmembrane domain of su9 fused to mouse dihydrofolate reductase (presu9(1-112)-dhfr). this protein attains the correct topology across the inner membrane (nout-cin) following import. the tr ...19957628445
isolation of a functional homolog of the cell cycle-specific nima protein kinase of aspergillus nidulans and functional analysis of conserved residues.to investigate the degree of conservation of the cell cycle-specific nima protein kinase of aspergillus nidulans, and to help direct its functional analysis, we cloned a homolog (designated nim-1) from neurospora crassa. over the catalytic domain nim-1 is 75% identical to nima, but overall the identity drops to 52%. nim-1 was able to functionally complement nima5 in a. nidulans. mutational analysis of potential activating phosphorylation sites found in nima, nim-1, and related protein kinases wa ...19957629122
purification, n-terminal amino acid sequence and partial characterization of a cu,zn superoxide dismutase from the pathogenic fungus aspergillus fumigatus.a superoxide dismutase (sod) has been purified to homogeneity from the fungal pathogen aspergillus fumigatus using a combination of cell homogenization, isoelectric focusing and gel filtration fplc. the n-terminal amino acid sequence of the purified enzyme demonstrated substantial homology to known cu,zn superoxide dismutases for a range of organisms, including neurospora crassa and saccharomyces cerevisiae. the enzyme subunit has a pi of 5.9, a relative molecular mass of 19 kda and a spectral a ...19957633574
the cellulase complex of neurospora crassa: cbh-1 cloning, sequencing and homologies.we describe the isolation, cloning and sequencing of the cellobiohydrolase 1 (ec 3.2.1.91)-encoding gene (cbh-1) of neurospora crassa. the nucleotide and amino-acid sequences have high homology with the cbh-1 of trichoderma reesei, humicola grisea and phanerochaete chrysosporium, with clear signal, catalytic, hinge and substrate-binding domains in that order.19957642129
the cpc-2 gene of neurospora crassa encodes a protein entirely composed of wd-repeat segments that is involved in general amino acid control and female fertility.phenotypic and molecular studies of the mutation u142 indicate that the cpc-2+ gene is required to activate general amino acid control under conditions of amino acid limitation in the vegetative growth phase, and for formation of protoperithecia in preparation for the sexual phase of the life cycle of neurospora crassa. the cpc-2 gene was cloned by complementation of the cpc-2 mutation in a his-2ts bradytrophic background. genomic and cdna sequence analysis indicated a 1636 bp long open reading ...19957651339
the aspergillus uvsh gene encodes a product homologous to yeast rad18 and neurospora uvs-2.the uvsh dna repair gene of aspergillus nidulans has been cloned by complementation of the uvsh77 mutation with a cosmid library containing genomic dna inserts from a wild-type strain. methylmethane sulfonate (mms)-resistant transformants were obtained on medium containing 0.01% mms, to which uvsh mutants exhibit high sensitivity. retransformation of uvsh77 mutants with the rescued cosmids from the mms-resistant transformants resulted in restoration of both uv and mms resistance to wild-type lev ...19957651340
the fusarium solani gene encoding kievitone hydratase, a secreted enzyme that catalyzes detoxification of a bean phytoalexin.among the antimicrobial phytoalexins produced by phaseolus vulgaris (french bean) is the prenylated isoflavonoid, kievitone. the bean pathogen, fusarium solani f. sp. phaseoli, secretes a glycoenzyme, kievitone hydratase (ec 4.2.1.95), which catalyzes conversion of kievitone to a less toxic metabolite. among f. solani strains, those that are highly virulent to p. vulgaris also produce kievitone hydratase constitutively, suggesting that the enzyme is a virulence factor. based on the n-terminal am ...19957655061
cloning and characterization of a heterologously expressed bifunctional chorismate synthase/flavin reductase from neurospora crassa.activities of all chorismate synthases (cs) so far analyzed are absolutely dependent upon reduced flavin. for monofunctional css, which represent the only class of css that have yet been cloned, the flavin must be reduced either (photo-)chemically or by a separable flavin reductase (fr) for in vitro activity. neurospora crassa cs, in contrast, possesses an intrinsic fr activity and represents the only firmly established member of a bifunctional class of css. to better understand this bifunctiona ...19957657620
cloning and expression of human deoxyhypusine synthase cdna. structure-function studies with the recombinant enzyme and mutant proteins.deoxyhypusine synthase catalyzes the first step in the post-translational formation of hypusine (n epsilon-(4-amino-2-hydroxybutyl)lysine). cdna clones encoding deoxyhypusine synthase were isolated from a human hela cell library. full-length cdna clones encoding a 369-amino acid protein (calculated molecular mass of 40,970 da) and a shorter cdna clone that would potentially encode a protein with an internal deletion of 56 amino acids (asp262-ser317) were isolated. the deduced amino acid sequence ...19957673224
characterization of sfp2, a putative sulfate permease gene of saccharomyces cerevisiae.the sfp2 gene of saccharomyces cerevisiae has been characterized. the deduced amino acid sequence contained twelve highly hydrophobic domains and showed 50, 47, 44 and 48% homologies to neurospora crassa sulfate permease ii (cys14), soybean gmak170 nodulin, human colon mucosa protein (dra) and a putative open reading frame (orf) downstream of escherichia coli prs (phosphoribosyl pyrophosphatate synthetase) gene, respectively, in the aligned regions. cells lacking sfp2 were viable and displayed n ...19957677785
a kluyveromyces lactis gene homologue to aac2 complements the saccaromyces cerevisiae op1 mutation.a mutation (op1) in the saccharomyces cerevisiae aac2 gene, which codes for the most abundant adp/atp carrier isoform, results in lack of mitochondrial-dependent growth and in an as yet unexplained petite-negative phenotype. a gene from the petite-negative yeast kluyveromyces lactis has been isolated by complementing in multicopy the op1 mutation of s. cerevisiae. this gene, designated kiaac, can complement the petite-negative phenotype of op1 as well as its inability to grow on nonfermentable c ...19957736606
limitations to in vivo import of hydrophobic proteins into yeast mitochondria. the case of a cytoplasmically synthesized apocytochrome b.the apocytochrome b gene, exclusively encoded by the mitochondrial genome, was engineered so that it could be expressed in the yeast cytoplasm. different combinations of the apocytochrome b transmembrane domains were produced in the form of hybrid proteins fused to both the n-terminal mitochondrial targeting sequence of the atpase subunit 9 from neurospora crassa and to a cytoplasmic version of the bi4 rna maturase, localised on the n-terminal and c-terminal sides, respectively, of the hydrophob ...19957737175
comparison of the mutagenicity and mutagen specificity of ethylenimine with triethylenemelamine in the ad-3 region of heterokaryon 12 of neurospora crassa.studies have been performed to compare the mutagenicity and mutagenic specificity of the trifunctional alkylating agent, triethylenemelamine (tem), and a closely related monofunctional agent, ethylenimine (ei), in the adenine-3 (ad-3) region of a 2-component heterokaryon (h-12) of neurospora crassa. the primary objective of our studies was to characterize the genetic damage produced by each agent with regard to (1) mutagenic potency, and (2) the spectrum of specific-locus mutations induced in a ...19957739603
cloning and expression of cdna encoding a protein that binds a palindromic promoter element essential for induction of fungal cutinase by plant cutin.previous studies showed that a palindromic sequence located at -159 base pairs is essential for induction of cutinase gene in fusarium solani f. sp. pisi (nectria haematococca mating type vi) by the hydroxy fatty acids from plant cutin and that a 50-kda nuclear protein binds to a promoter that contains this element. screening of a phage lambda gt11 expression library with the concatenated palindromic sequence as the probe identified a cdna encoding a palindrome-binding protein (pbp). nucleotide ...19957744822
development of primer sets designed for use with the pcr to amplify conserved genes from filamentous ascomycetes.we constructed nine sets of oligonucleotide primers on the basis of the results of dna hybridization of cloned genes from neurospora crassa and aspergillus nidulans to the genomes of select filamentous ascomycetes and deuteromycetes (with filamentous ascomycete affiliations). nine sets of primers were designed to amplify segments of dna that span one or more introns in conserved genes. pcr dna amplification with the nine primer sets with genomic dna from ascomycetes, deuteromycetes, basidiomycet ...19957747954
cloning and identification of arp1, an actin-related protein from pneumocystis carinii.the complete pneumocystis carinii arp1 gene has been sequenced from two cdna clones. the gene encodes a protein 385 bp in length with an estimated size of 45,000 kd. the a + t% for the arp1 gene and a 900-bp sequence upstream of the gene were 63.7% and 70.3%, respectively. these values are consistent with a + t codon preference displayed by p. carinii and are similar to values reported for other p. carinii genes. the predicted amino acid sequence of the p. carinii arp1 protein had a similarity o ...19957757056
disruption of the gene for hsp30, an alpha-crystallin-related heat shock protein of neurospora crassa, causes defects in thermotolerance.the alpha-crystallin-related heat shock proteins are produced by all eukaryotes, but the role of these proteins in thermoprotection remains unclear. to investigate the function of one of these proteins, we disrupted expression of the single-copy hsp30 gene of neurospora crassa, using repeat-induced point mutagenesis, and we generated and characterized mutant strains that were deficient in hsp30 synthesis. these strains could grow at high temperature and they acquired thermotolerance from a heat ...19957761443
a human homolog of the mitochondrial protein import receptor mom19 can assemble with the yeast mitochondrial receptor complex.import of preproteins into mitochondria requires transport machineries in both mitochondrial membranes that have been characterized in saccharomyces cerevisiae and neurospora crassa. by cdna analysis, we identified a human protein of 16 kda with significant overall homology to the fungal mitochondrial import receptor mom19, including the three typical characteristics: a hydrophobic n-terminal segment, a tetratrico peptide motif in the middle and a negatively charged c-terminus. the human mom19 h ...19957498524
isolation and characterization of genes expressed uniquely during appressorium formation by colletotrichum gloeosporioides conidia induced by the host surface wax.appressorium formation in germinating colletotrichum gloeosporioides is induced by the surface wax of the host, the avocado fruit. to elucidate the mechanism by which differentiation of appressorium formation is induced, the fungal genes specifically activated by this host signal were sought. from a cdna library of the transcripts present in appressorium-forming conidia, the clones representing nongerminating conidia were removed by hybridization with cdnas synthesized from the nongerminating co ...19957770033
a eukaryotic gene encoding an endonuclease that specifically repairs dna damaged by ultraviolet light.many eukaryotic organisms, including humans, remove ultraviolet (uv) damage from their genomes by the nucleotide excision repair pathway, which requires more than 10 separate protein factors. however, no nucleotide excision repair pathway has been found in the filamentous fungus neurospora crassa. we have isolated a new eukaryotic dna repair gene from n.crassa by its ability to complement uv-sensitive escherichia coli cells. the gene is altered in a n.crassa mus-18 mutant and responsible for the ...19957774597
isolation and identification of adenosine triphosphoribosyl nicotinamide adenine dinucleotidephosphate from azotobacter vinelandii.a novel type of pyridine nucleotide, containing two adenosine triphosphate ribose residues rather than one, was isolated from azotobacter vinelandii strain o. the nucleotide was shown to be 2"- or 3"-(2'-phosphoadenosine-5'-diphosphoribosyl)nicotinamide adenine dinucleotide phosphate, in which 2'-phospho-5'-diphosphoadenosylribose was glycosidically linked to the nadp at position 2' or 3' of the nicotinamide mononucleotide moiety. the atpribosylnadp did not show coenzyme activity for yeast gluco ...19957775384
molecular cloning and analysis of nre, the major nitrogen regulatory gene of penicillium chrysogenum.we have isolated the penicillium chrysogenum nre gene which is homologous to the major nitrogen regulatory genes area from aspergillus nidulans and nit-2 from neurospora crassa. overall, nre shows 60% identity to area and 30% identity to nit-2 at the amino-acid level. the gene encodes a protein of 835 amino-acid residues and contains a single cys2/cys2-type zinc finger with an adjacent basic region and a putative acidic activation region. in the dna-binding domain, 98% of the amino-acid residues ...19957788718
ectopic integration of transforming dna is rare among neurospora transformants selected for gene replacement.in a variety of organisms, dna-mediated transformation experiments commonly produce transformants with multiple copies of the transforming dna, including both selected and unselected molecules. such "cotransformants" are much more common than expected from the individual transformation frequencies, suggesting that subpopulations of cells, or nuclei, are particularly competent for transformation. we found that neurospora crassa transformants selected for gene replacement at the am gene had not ef ...19957789758
laccase component of the ceriporiopsis subvermispora lignin-degrading system.laccase activity in the lignin-degrading fungus ceriporiopsis subvermispora was associated with several proteins in the broth of cultures grown in a defined medium. activity was not increased significantly by adding 2,5-xylidine or supplemental copper to the medium. higher activity, associated with two major isoenzymes, developed in cultures grown on a wheat bran medium. these two isoenzymes were purified to homogeneity. l1 and l2 had isoelectric points of 3.4 and 4.8, molecular masses of 71 and ...19957793921
a phosphate-repressible, high-affinity phosphate permease is encoded by the pho-5+ gene of neurospora crassa.the pho-5+ gene of neurospora crassa, which encodes a high-affinity phosphate permease, has been cloned and analyzed. the deduced orf of 1707 nucleotides is interrupted by a single 63-nt intron and codes for a protein of 569 amino acids (aa). this aa sequence has 48% identity with the high-affinity phosphate transporter of saccharomyces cerevisiae, pho84. the pho-5 null mutants have no obvious phenotype. strains which contain a null mutation in pho-4, which encodes an additional high-affinity ph ...19957883177
identification of yeast mas17 encoding the functional counterpart of the mitochondrial receptor complex protein mom22 of neurospora crassa.mom22 of neurospora crassa was suggested to be required for the transfer of mitochondrial precursor proteins from the receptors to the protein translocation machinery. we isolated a yeast mutant the viability of which depended on the expression of the introduced n. crassa mom22 gene. the mutant cells showed defects in protein import into mitochondria when the cells were depleted of mom22. by screening for suppressor genes for the mutant, we could identify the yeast gene mas17 encoding the functi ...19957805891
light and developmental regulation of the gene con-10 of neurospora crassa.the gene con-10 of neurospora crassa is expressed preferentially during conidiation and following illumination of vegetative mycelia with blue light. in this study we have examined the segmental locations of the genetic elements associated with con-10 that are responsible for light and developmental expression. a translational fusion was prepared between the initial segment of con-10 and escherichia coli lacz. deletions were then introduced into the con-10 upstream region associated with this tr ...19957851642
triethylenemelamine: induction of specific-locus mutations in the ad-3 region of heterokaryon 12 of neurospora crassa.the mutagenicity of the trifunctional alkylating (or cross-linking) agent tem (triethylenemelamine or 2,4,6-tris(1-aziridinyl)-1,3,5-triazine) in the adenine-3 (ad-3) region was studied with a two-component heterokaryon (h-12) of neurospora crassa. the objective was to characterize the genetic damage produced by this chemical to determine the spectrum of specific-locus mutations induced in a lower eukaryotic organism and to compare this spectrum with that induced in the mouse. specific-locus mut ...19957870102
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