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alkaline protease deficiency in the cr-1 (crisp) mutant of neurospora crassa.the adenyl cyclase deficient cr-1 mutant of neurospora crassa grew poorly in bovine serum albumin as an alternative and only source of either sulfur, nitrogen or carbon. the low growth of the cr-1 mutant in protein was correlated with limited secretion of extracellular alkaline protease. the defect was specific for the cr-1 mutant and was suppressed by exogenous cyclic amp. cyclic amp relieved protease deficiency under carbon, nitrogen or sulfur limiting conditions to unequal extents. protease s ...19863026533
purification and properties of a single strand-specific endonuclease from mouse cell mitochondria.a nuclease was purified from mitochondria of the mouse plasmacytoma cell line, mcp-11 which acts on single-stranded dna endonucleolytically and appears to have no activity upon native dna. it degrades unordered rna somewhat more effectively than it does dna. the enzyme activity and the major detectable polypeptide migrate to a position corresponding to an mr of 37,400 on denaturing polyacrylamide gels; in its native form the activity has an s value of 4.7, which corresponds to a molecular weight ...19863027656
behaviour of recombinant plasmids in aspergillus nidulans: structure and stability.a pyrg- aspergillus strain was transformed with plasmid pdjb-1, derived from pbr325 by insertion of the neurospora crassa pyr4 gene (orotidine 5'-phosphate carboxylase), giving mitotically unstable transformants. aspergillus dna which acted as an "autonomously replicating sequence" (ars) in yeast was inserted into pdjb-1 and the resulting construct, pdjb12.1, gave mitotically stable transformants when introduced into aspergillus. transformants obtained with pdjb-1 and pdjb12.1 gave few pyr- prog ...19863329034
molybdenum cofactor: a compound in the in vitro activation of both nitrate reductase and trimethylamine-n-oxide reductase activities in escherichia coli k12.nitrate reductase (nitrite: (acceptor) oxidoreductase, ec 1.7.99.4) and trimethylamine n-oxide reductase (nadh : trimethylamine-n-oxide oxidoreductase, ec 1.6.6.9) activities were reconstituted by incubation of the association factor fa (the putative product of the chlb gene) with the soluble extract of the chlb mutant grown anaerobically in the presence of trimethylamine n-oxide. when soluble extracts of the chlb mutant grown on 10 mm sodium tungstate, a molybdenum competitor, were used in comp ...19863524687
activation in vitro of respiratory nitrate reductase of escherichia coli k12 grown in the presence of tungstate. involvement of molybdenum cofactor.the chlorate-resistant (chlr) mutants are pleiotropically defective in molybdoenzyme activity. the inactive derivative of the molybdoenzyme, respiratory nitrate reductase, present in the cell-free extract of a chlb mutant, can be activated by the addition of protein fa, the probable active product of the chlb locus. protein fa addition, however, cannot bring about the activation if 10 mm sodium tungstate is included in the culture medium for the chlb strain. the inclusion of a heat-treated prepa ...19863525161
further characterization of trimethylamine n-oxide reductase from escherichia coli, a molybdoprotein.escherichia coli trimethylamine n-oxide (tmao) reductase i, the major enzyme among inducible tmao reductases, was purified to homogeneity by an improved method including heat treatment, ammonium sulfate precipitation, and chromatographies on bio-gel a-1.5m, deae-cellulose, and reactive blue-agarose. the molecular weight was estimated by gel filtration to be approximately 200,000. a single subunit peptide with a molecular weight of 95,000 was found by sodium dodecyl sulfate-polyacrylamide gel ele ...19863528139
localization of alkaline phosphatase activity at microbody membranes of neurospora crassa and aspergillus nidulans.hyphal cells of neurospora crassa and aspergillus nidulans, grown in sabouraud glucose broth or in a defined medium with xanthine or its catabolites as the nitrogen source, contained single membrane-bound organelles cytochemically identified as microbodies. modified gomori procedures at the ultrastructural level revealed putative alkaline phosphatase activity sites in thin sections of cells of both species of fungi. microbody membranes displayed electron opaque deposits (lead phosphate) which we ...19862948778
mitochondrial gene urfn of neurospora crassa codes for a long polypeptide with highly repetitive structure.the mitochondrial dna of neurospora crassa contains a long potential gene, designated urfn, which is located immediately downstream from the co1 gene. these two genes are encoded in different reading frames and overlap by 13 codons. urfn is 633 triplets long and terminates at a uag stop codon. its codon usage is atypical for n. crassa mitochondrial exons and introns, and resembles that of the long open reading frame (orf) of the mitochondrial plasmid present in n. crassa strain mauriceville. mul ...19862949084
sequence analysis and transformation by the catabolic 3-dehydroquinase (qute) gene from aspergillus nidulans.the induction of catabolic 3-dehydroquinase by quinic acid in aspergillus nidulans has been shown to involve transcriptional control and yields a single major 0.8 kb mrna. the nucleotide sequence of the catabolic 3-dehydroquinase qute gene has been determined and contains a single uninterrupted open reading frame of 462 bases encoding a 16,505 da protein of 153 residues. comparison with the corresponding qa2 gene of neurospora crassa reveals the absence of 75 nucleotides encoding 25 amino acids ...19862949740
purification and characterization of 3-dehydroquinase from escherichia coli.a procedure has been developed for the purification of 3-dehydroquinase from escherichia coli. homogeneous enzyme with specific activity 163 units/mg of protein was obtained in 19% overall yield. the subunit mr estimated from polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate was 29,000. the native mr, estimated by gel permeation chromatography on sephacryl s-200 (superfine) and on tsk g3000sw, was in the range 52,000-58,000, indicating that the enzyme is dimeric. the ...19862950851
labeling of individual amino acid residues in the membrane-embedded f0 part of the f1 f0 atp synthase from neurospora crassa. influence of oligomycin and dicyclohexylcarbodiimide.three f0 subunits and the f1 subunit beta of the atp synthase from neurospora crassa were labeled with the lipophilic photoactivatable reagent 3-(trifluoromethyl)-3-(m-[125i]iodophenyl)diazirine ([125i]tid). in the proteolipid subunit which was the most heavily labeled polypeptide labeling was confined to five residues at the nh2-terminus and five residues at the c-terminus of the protein. labeling occurred at similar positions compared with the homologous protein (subunit c) in the atp synthase ...19862869944
topological studies suggest that the pathway of the protons through f0 is provided by amino acid residues accessible from the lipid phase.the structure of the f0 part of atp synthases from e. coli and neurospora crassa was analyzed by hydrophobic surface labeling with [125i]tid. in the e. coli f0 all three subunits were freely accessible to the reagent, suggesting that these subunits are independently integrated in the membrane. labeled amino acid residues were identified by edman degradation of the dicyclohexylcarbodiimide binding (dccd) proteins from e. coli and neurospora crassa. the very similar patterns obtained with the two ...19862874840
primary structure of the neurospora plasma membrane h+-atpase deduced from the gene sequence. homology to na+/k+-, ca2+-, and k+-atpase.the gene for the neurospora crassa plasma membrane h+-atpase has been cloned and sequenced. the gene encodes for a protein of 920 amino acids with a molecular weight of 100,002. the coding region is interrupted by four introns: three near the amino terminus and one near the carboxyl terminus. the deduced amino acid sequence of the n. crassa plasma membrane h+-atpase exhibits 75% homology to the amino acid sequence of the saccharomyces cerevisiae plasma membrane h+-atpase. also, an amino acid com ...19862876992
the atp synthase subunit 9 gene of aspergillus nidulans: sequence and transcription.we have determined the nucleotide sequence of the aspergillus nidulans nuclear gene olic31, which encodes subunit 9 of mitochondrial atp synthase. the open reading frame contains no introns and specifies a predicted protein of 143 amino acids comprising a pre-sequence of 62 residues and a mature protein of 81 residues. the amino acid homology with the equivalent neurospora crassa protein is 50% for the pre-sequence and 80% for the mature protein. a comparison with this and other imported mitocho ...19862880279
yeast mitochondrial atpase subunit 8, normally a mitochondrial gene product, expressed in vitro and imported back into the organelle.subunit 8 of yeast mitochondrial f1f0-atpase is a proteolipid made on mitochondrial ribosomes and inserted directly into the inner membrane for assembly with the other f0 membrane-sector components. we have investigated the possibility of expressing this extremely hydrophobic, mitochondrially encoded protein outside the organelle and directing its import back into mitochondria using a suitable n-terminal targeting presequence. this report describes the successful import in vitro of atpase subuni ...19862881782
neurospora crassa mitochondria contain two forms of a 4'-phosphopantetheine-modified protein.when neurospora crassa was labeled with [14c]pantothenic acid during growth, the mitochondrial fraction contained two bands of radioactivity of mr 19,000 and 22,000 by sodium dodecyl sulfate gel electrophoresis. the 19-kda band was converted to the 22-kda band by four treatments which are characteristic of the cleavage of a thioester bond: dithiothreitol and 2-mercaptoethanol at basic but not neutral ph, alkaline methanolysis, sodium borohydride in tetrahydrofuran, and hydroxylamine at neutral p ...19862937780
a study of the messenger rna encoding pyruvate kinase of neurospora crassa.in neurospora crassa, there is a single pyruvate kinase (pk) consisting of four identical subunits of approximately 60k daltons. northern and dot blot hybridization studies, using most of the yeast pyruvate kinase gene as a probe, suggest the presence of two distinct mrna species for pyruvate kinase, separable on the basis of the length of their polyadenylated tails, by oligo(dt)cellulose chromatography. these messages are present in polysomes, immuno-precipitated by anti-pk antibodies, indicati ...19862941081
a cloned tryptophan-synthesis gene from the ascomycete cochliobolus heterostrophus functions in escherichia coli, yeast and aspergillus nidulans.a gene (trp1) in the tryptophan biosynthetic pathway of the fungal plant pathogen cochliobolus heterostrophus was isolated by complementation of an escherichia coli trpf mutant which lacked phosphoribosylanthranilate isomerase (prai) activity. the cloned gene also complemented an e. coli trpc mutant lacking indoleglycerolphosphate synthase (igps) activity, a yeast trp1 mutant missing prai activity and an aspergillus nidulans trpc mutant. it functioned in e. coli and a. nidulans without apparent ...19862941339
the effect of papulacandin b on (1----3)-beta-d-glucan synthetases. a possible relationship between inhibition and enzyme conformation.the antibiotic, papulacandin b, inhibited growth or (1----3)-beta-d-glucan synthetase (or both) in the fungi saccharomyces cerevisiae, hansenula anomala, neurospora crassa, cryptococcus laurentii, schizophyllum commune and wangiella dermatitidis. no effect was observed on achlya ambisexualis. there was no apparent correlation between the inhibition of growth and that of the synthetase. with most of the fungal extracts, the inhibition of glucan synthetase by papulacandin b became less pronounced ...19862942248
biochemical comparison of the neurospora crassa wild type and the temperature-sensitive and leucine-auxotroph mutant leu-5. purification of the cytoplasmic and mitochondrial leucyl-trna synthetases and comparison of the enzymatic activities and the degradation patterns.the cytoplasmic leucyl-trna synthetases of neurospora crassa wild type (grown at 37 degrees c) and mutant (grown at 28 degrees c) were purified approximately 1770-fold and 1440-fold respectively. additional enzyme preparations were carried out with mutant cells grown for 24 h at 28 degrees c and transferred then to 37 degrees c for 10-70 h of growth. the mitochondrial leucyl-trna synthetase of the wild type was purified approximately 722-fold. the mitochondrial mutant enzyme was found only in tr ...19862942398
regulation of fungal cell wall growth: a guanine nucleotide-binding, proteinaceous component required for activity of (1----3)-beta-d-glucan synthase.by treatment with detergent and nacl, particulate (1----3)-beta-d-glucan synthase (ec 2.4.1.34) from hansenula anomala or neurospora crassa was dissociated into a "soluble fraction" and a "membrane fraction." each fraction alone was almost inactive, but enzymatic activity could be reconstituted by mixing the two fractions and adding gtp or one of its analogs. based on their lability to heat and to incubation with trypsin, the activity in both fractions is proteinaceous. the active component in t ...19862942941
compartmental and regulatory mechanisms in the arginine pathways of neurospora crassa and saccharomyces cerevisiae. 19862945985
isolation and partial nucleotide sequence of the laccase gene from neurospora crassa: amino acid sequence homology of the protein to human ceruloplasmin.the laccase (benzenediol:oxygen oxidoreductase, ec 1.10.3.2) gene from neurospora crassa was cloned and part of its nucleotide sequence corresponding to the carboxyl-terminal region of the protein has been determined. the gene was cloned by cdna synthesis with a laccase-specific synthetic deoxyundecanucleotide as primer and poly(a) rna isolated from cycloheximide-treated n. crassa cultures as template. based on the nucleotide sequence of the cdna obtained, a unique 21-mer was synthesized and use ...19862947240
inversions and recombinations in mitochondrial dna of the (sg-1) cytoplasmic mutant in two neurospora species.the mitochondrial dnas of [sg-1] cytoplasmically-mutant and wild-type strains of neurospora crassa and neurospora sitophila were examined by comparative restriction endonuclease analyses. the mtdna of n. sitophila wild type of whitehouse differs from type ii mtdna of n. crassa by insertions of 3.3 kb in ecori-9, and 1.2 kb in ecori-3, and a deletion of 1.1 kb in ecori-5. these dna heteromorphisms provided convenient markers for tracing n. crassa [sg-1] mtdna during and after its transfer into n. ...19862832078
isolation and identification of the aspergillus nidulans gdha gene encoding nadp-linked glutamate dehydrogenase.the neurospora crassa am gene was used as a heterologous probe to identify clones from two independently constructed aspergillus nidulans gene libraries. these clones have a common hindiii 1.85 kb fragment. this a. nidulans nucleotide stretch hybridises to a n. crassa 2.7 kb bamhi fragment of wild type dna but not to a co-migrating fragment from the dna of the n. crassa am132 deletion mutant. one a. nidulans clone was shown to complement the n. crasse am132 deletion strain. the n. crassa transfo ...19862834076
molybdopterin cofactor from methanobacterium formicicum formate dehydrogenase.the molybdopterin cofactor from the formate dehydrogenase of methanobacterium formicicum was studied. the cofactor was released by guanidine denaturation of homogeneous enzyme, which also released greater than 80% of the molybdenum present in the enzyme. the anoxically isolated cofactor was nonfluorescent, but after exposure to air it fluoresced with spectra similar to those of described molybdopterin cofactors. aerobic release from acid-denatured formate dehydrogenase in the presence of i2 and ...19863700335
purification and properties of nitrate reductase from mitsuokella multiacidus.nitrate reductase of mitsuokella multiacidus (formerly bacteroides multiacidus) was solublized from the membrane fraction with 1% sodium deoxycholate and purified 40-fold by immunoaffinity chromatography on the antibody-affi-gel 10 column. the preparation showed a major band (86% of total protein) with enzyme activity and a minor band on polyacrylamide gel after disc electrophoresis in the presence of 0.1% triton x-100. sodium dodecyl sulfate-polyacrylamide gel electrophoresis gave a major band, ...19863711052
an altered invertase in the cot-2 mutant of neurospora crassa.because the cot-2 and inv loci of neurospora crassa are closely linked, the invertase from the morphological mutant, cot-2, was examined. the cot-2 strains produce an invertase with altered heat sensitivity, km, and ratio of heavy to light forms. the cellular localization of cot-2 invertase is different from that of the wild type. there were no observable changes in the energy of activation or the ph optimum of cot-2 invertase, and some of the differences detected were not apparent under culture ...1986239095
mode of action and properties of xylanase and beta-xylosidase from neurospora crassa.extracellular beta-xylosidase (1,4-beta-d-xylan xylohydrolase, ec 3.2.1.37) from culture filtrates of neurospora crassa was purified to homogeneity by preparative isoelectric focusing followed by gel electrophoresis. the molecular weight of the purified xylosidase was 83,000 d and the k(m) on p-nitrophenyl-beta-d-xyloside was 0.047mm. the homogeneous xylanase (1,4-beta-d-xylan xylanohydrolase, ec 3.2.1.8) and beta-xylosidase showed differences in their mode of action towards xylooligosaccharides ...198618555300
influence of the carbon source on glycerol kinase activity in neurospora crassa.the level of glycerol kinase activity in neurospora crassa was shown to change in response to resuspension of sucrose-grown mycelia in fresh medium containing a new carbon source: the magnitude of the change depended on the new carbon source provided. certain carbon sources, such as glucose and fructose, inhibited the small increase that occurred in the absence of any carbon source. others, and in particular deoxyribose, galactose, glycerol and ribose, greatly enhanced this increase. the activit ...1987174743
complex iii from mitochondria on neurospora crassa: purification, characterization, and resolution. 1987213696
effect of carbon source on enzymes involved in glycerol metabolism in neurospora crassa.specific activities of eight enzymes involved in glycerol metabolism were determined in crude extracts of three strains of neurospora crassa after growth on six different carbon sources. one of the strains was wild type, which grew poorly on glycerol as sole carbon source; the other two were mutant strains which were efficient glycerol utilizers. a possible basis for this greater efficiency of glycerol utilization was catabolite repression of glyceraldehyde kinase by glycerol in wild type, and t ...1987211971
development of a homologous transformation system for aspergillus niger based on the pyrg gene.the development of a homologous transformation system for aspergillus niger is described. the system is based on the use of an orotidine-5'-phosphate decarboxylase deficient mutant (pyrg) and a vector, pab4-1, which contains the functional a. niger pyrg gene as a selection marker. transformation of the a. niger pyrg mutant with pab4-1 resulted in the appearance of stable pyr+ transformants at a frequency of 40 transformants per microgram of dna. in 90% of these transformants integration had occu ...19873472035
transformation of aspergillus oryzae using the a. niger pyrg gene.a transformation system for aspergillus oryzae based on the orotidine-5'-phosphate decarboxylase gene (pyrg) was developed. transformation frequencies of up to 16 transformants per microgram of dna were obtained with the vector pab4-1, which carries the pyrg gene of a. niger. southern blotting analysis showed that vector dna sequences were integrated into the chromosomal dna, in various copy numbers and presumably at different sites. efficient cotransformation of an unselectable gene was also sh ...19873481025
identification and isolation of a putative permease gene in the quinic acid utilization (qut) gene cluster of aspergillus nidulans.mutations in the qutd gene of aspergillus nidulans cause the loss of ability to grow upon quinic acid as sole carbon source in media at normal ph 6.5 and failure to induce three enzyme activities specifically required for metabolism to protochatechuic acid. all 9 qutd mutants recovered are recessive and have been found to be ph sensitive, growing strongly on quinic acid media at ph 3.5 and producing significant induced enzyme activities. these properties are consistent with the hypothesis that t ...19872835177
neurospora crassa nuclear genome contains analogy of saccharomyces cerevisiae genes for ribosomal rna processing.neurospora crassa wild type genome shows dna sequences which are homologous to the sequences present in the rrna processing genes of the yeast saccharomyces cerevisiae. five such processing genes from yeast, viz., rna1 through rna5, cloned in plasmid pbr322 were transformed in escherichia coli strain le392. southern blots containing dnas from these clones were restricted with several restriction endonucleases along with dnas from lambda phage, rice (plant) and neuroblastoma (animal), were hybrid ...19872835180
transformation of aspergillus niger using the homologous orotidine-5'-phosphate-decarboxylase gene.a homologous transformation system for the filamentous fungus aspergillus niger has been developed, based on the orotidine-5'-phosphate-decarboxylase gene. a. niger pyr- mutants have been selected from 5-fluoro-orotic acid resistant mutants. these mutants were found to comprise two complementation groups, pyra and pyrb. the a. niger omp-decarboxylase gene was isolated from a gene library by heterologous hybridization with the neurospora crassa pyr4 gene. the cloned gene is capable to transform a ...19872836081
involvement of chla, e, m, and n loci in escherichia coli molybdopterin biosynthesis.all molybdenum enzymes except nitrogenase contain a common molybdenum cofactor, whose organic moiety is a novel pterin called molybdopterin (mpt). to assist in elucidating the biosynthetic pathway of mpt, two mpt-deficient mutants of escherichia coli k-12 were isolated. they lacked activities of the molybdenum enzymes nitrate reductase and formate dehydrogenase, did not reconstitute apo nitrate reductase from a neurospora crassa nit-1 strain, and did not yield form a, a derivative of mpt. by p1 ...19872947896
human liver cdna clones encoding proteolipid subunit 9 of the mitochondrial atpase complex.clones encoding the proteolipid subunit 9 of the mitochondrial atpase complex have been isolated from a lambda gt10 library of human liver cdna sequences, using a probe of neurospora crassa cdna encoding subunit 9. from nucleotide sequence analysis it is concluded that the amino acid sequence of mature human subunit 9 is identical to that of its bovine counterpart. by comparing the sequence of two cdna clones (denoted human 1 and 2) to those of two bovine cdna clones (denoted p1 and p2) recently ...19872883974
studies on nitrate reductase of clostridium perfringens. iv. identification of metals, molybdenum cofactor, and iron-sulfur cluster.nitrate reductase of clostridium perfringens was purified by an improved method using immuno-affinity chromatography. the purified preparation contained mo, fe, and acid-labile sulfide; the mo content was 1 mol per mol and the fe 3.7 mol per mol of the enzyme. the inactive enzyme obtained from cells grown in the presence of tungstate did not hold mo but contained 1 mol of w. the content of fe was not increased. the presence of molybdenum cofactor in the nitrate reductase was indicated by the for ...19872884214
mutation of a conserved glycine residue modifies the vanadate sensitivity of the plasma membrane h+-atpase from schizosaccharomyces pombe.the structural gene pma+1 for the h+-atpase from the fission yeast schizosaccharomyces pombe has been isolated and sequenced. the intron-less gene encodes for a protein of mr = 99,769 which is 75% homologous to those of saccharomyces cerevisiae and neurospora crassa. the s. pombe pma+1 gene complements not only s. pombe pma-1-1 but also s. cerevisiae pma-1-4 mutants selected for in vitro vanadate-resistant atpase activity. the sequence of the s. pombe mutant pma-1-1 allele reveals that the glyci ...19872891694
clathrin coated vesicles in neurospora crassa.electropherograms of neurospora crassa homogenates showed a polypeptide with a mobility slightly lower than that of a standard sample of clathrin (from bovine brain). subcellular fractionation of the homogenate resulted in a 20-fold enrichment of the putative n. crassa clathrin in the microsomal fraction. further fractionation of the microsomal fraction by glass bead permeation chromatography yielded a fraction enriched about 150-fold relative to the homogenate. coated vesicles (42.5 +/- 2.5 nm ...19872892127
fungal small nuclear ribonucleoproteins share properties with plant and vertebrate u-snrnps.snrnas with properties closely related to those of the major vertebrate u-snrnas are present in the fungi aspergillus nidulans, neurospora crassa and schizosaccharomyces pombe. these rnas possess a tri-methyl guanosine cap structure and a subset cross-hybridizes with human u1 and u2 clones. in the form of snrnps, snrnas from these fungi as well as from saccharomyces cerevisiae and pea plants are immunoprecipitated by human and anti-sm or anti-(u1)rnp autoimmune antibodies. on micro-injection int ...19872953599
purification and characterization of arginase from neurospora crassa.we have purified an enzymatically active form of arginase from a wild-type strain of neurospora crassa to homogeneity. the enzyme has a subunit molecular weight of 38,300 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the native protein migrated as a hexamer during gel-filtration chromatography with an apparent molecular weight of 266,000. the enzyme exhibited hyperbolic kinetics at ph 9.5 with an apparent km for arginine of 131 mm. antiserum was prepared against the ...19872953715
the neurospora crassa metallothionein gene. regulation of expression and chromosomal location.the promoter region of the neurospora crassa metallothionein gene contains no sequences which are similar to the mammalian or the yeast metal responsive elements (münger, k., germann, u. a., and lerch, k. (1985) embo j. 4, 2665-2668). we therefore studied the regulation of expression of the n. crassa metallothionein gene in response to different metal ions (cu2+, cd2+, zn2+, co2+, and ni2+) by northern analysis. only copper led to the induction of metallothionein mrna. in n. crassa cultures inoc ...19872953720
ornithine decarboxylase from neurospora crassa. purification, characterization, and regulation by inactivation.ornithine decarboxylase, a highly regulated enzyme of the polyamine pathway, was purified 670-fold from mycelia of neurospora crassa that were highly augmented for enzyme activity. the enzyme is significantly different from those reported from three other lower eucaryotic organisms: saccharomyces cerevisiae, physarum polycephalum, and tetrahymena pyriformis. instead, the enzyme closely resembles the enzymes from mammals. the mr = 110,000 enzyme is a dimer of 53,000 da subunits, with a specific a ...19872953728
complementation of area- regulatory gene mutations of aspergillus nidulans by the heterologous regulatory gene nit-2 of neurospora crassa.loss-of-function mutations in the regulatory gene area of aspergillus nidulans prevent the utilization of a wide variety of nitrogen sources. the phenotypes of nit-2 mutants of neurospora crassa suggest that this gene may be analogous to the area gene. transformation has been used to introduce a plasmid containing the nit-2 gene into a. nidulans. the nit-2 gene of neurospora complemented mutations in the area gene, restoring the ability to use a variety of nitrogen sources. this indicated that t ...19872954160
nucleotide sequence and characterization of the pyrf operon of escherichia coli k12.the pyrf gene of escherichia coli k12, which encodes the pyrimidine biosynthetic enzyme orotidine-5'-monophosphate (omp) decarboxylase, is part of an operon that includes a downstream gene designated orff. the orff gene product is a small polypeptide of unknown function. the nucleotide sequence of a 1549-base pair chromosomal fragment containing this operon was determined. an open reading frame capable of encoding the 27-kda omp decarboxylase subunit was identified and shown to be the pyrf struc ...19872956254
a portable signal causing faithful dna methylation de novo in neurospora crassa.methylation of cytosine residues in eukaryotic dna is common, but poorly understood. typically several percent of the cytosines are methylated; however, it is unclear what governs which sequences eventually become modified. neurospora crassa dna containing the "zeta-eta" (zeta-eta) region, which is a region of unusually heavy methylation, was tested for its ability to direct dna methylation de novo. dna stripped of its methylation by propagation in escherichia coli was reintroduced into neurospo ...19872958937
luminescence emission from the cu(i)-thiolate complex in metallothioneins.the luminescence emission properties of cu-metallothioneins (from neurospora crassa, agaricus bisporus and livers of bedlington terriers affected by copper toxicosis) as well as of (cu,zn)-metallothionein from bovine fetal liver are reported. upon excitation in the u.v., these proteins emit a largely red-shifted luminescence with a maximum at 565 nm attributable to the cu(i)-thiolate chromophores of the proteins. differences in the shapes of the spectra and the emission intensity are observed wi ...19872959510
orientation of enzymic domains in tryptophan synthase of neurospora crassa: an immunoblot analysis of trp3 mutant products.extracts of 52 trp3 mutants of neurospora crassa were tested for the presence of serologically cross-reacting material by the method of electrophoretic blot analysis. the test antigen was obtained by excision of lightly stained bands of denatured pure tryptophan synthase after sds-polyacrylamide gel electrophoresis. rabbit antisera raised against this antigen neutralized and precipitated native tryptophan synthase. of the 52 strains, 19 exhibited banding patterns similar to wild type on electrop ...19872959839
molecular genetic analysis of the pyr-4 gene of neurospora crassa.by means of s1 nuclease mapping, one transcription origin and three termini are identified for the pyr-4 gene of neurospora crassa, the same origin being used also by escherichia coli on the cloned gene. translation of the clone in mini-cells gives a 50,000 dalton gene product, the same size as that determined for the neurospora native enzyme. putative caat and tata boxes, and upstream and downstream potential secondary structures, are identified.19872959843
mitochondrial porin of neurospora crassa: cdna cloning, in vitro expression and import into mitochondria.cdna encoding porin of neurospora crassa, the major protein component of the outer mitochondrial membrane, was isolated and the nucleotide sequence was determined. the deduced protein sequence consists of 283 amino acids (29,979 daltons) and shows sequence homology of around 43% to yeast porin; however, no significant homology to bacterial porins was apparent. according to secondary structure predictions, mitochondrial porin consists mainly of membrane-spanning sided beta-sheets. porin was effic ...19872960519
role of siderophores in iron storage in spores of neurospora crassa and aspergillus ochraceus.spores of neurospora crassa 74a are lacking in ferritinlike iron pools, as demonstrated by mössbauer spectroscopic analysis. the cyclic hexapeptide siderophore ferricrocin constituted 47% of the total iron content in spores. after germination and growth, the ferricrocin iron pool disappeared, indicating that the metal was utilized. in spores of aspergillus ochraceus, 74% of the total iron content was bound by ferrichrome-type siderophores. siderophores may function as iron storage forms in funga ...19872960664
secretory protein translocation in a neurospora crassa in vitro system. hydrolysis of a nucleoside triphosphate is required for posttranslational translocation.an in vitro translocation system has been reconstituted with subcellular fractions from the cell wall-less mutant of neurospora crassa (fz;sg;os-1). prepro alpha factor and invertase, secretory proteins from yeast, were faithfully translocated and glycosylated by neurospora microsomes when presence cotranslationally in the neurospora translation system. when presence cotranslationally in the neurospora translation system, microsomes from canine pancreas(crm) could also translocate and glycosylat ...19872960680
isolation and characterization of a neurospora crassa ribosomal protein gene homologous to cyh2 of yeast.we have isolated and characterized a neurospora crassa gene homologous to the yeast cyh2 gene encoding l29, a cycloheximide sensitivity-conferring protein of the cytoplasmic ribosome. the cloned neurospora gene was isolated by cross-hybridization to cyh2. it was sequenced from both cdna and genomic clones. the coding region is interrupted by seven intervening sequences. its deduced amino acid sequence shows 70% homology to that of yeast ribosomal protein l29 and 60% homology to that of mammalian ...19872960953
biosynthesis of thiamin. different biosynthetic routes of the thiazole moiety of thiamin in aerobic organisms and anaerobic organisms.the nitrogen atom of glycine was incorporated into the thiazole moiety of thiamin in the aerobic microorganisms bacillus subtilis, pseudomonas putida, saccharomyces cerevisiae, mucor racemosus, neurospora crassa, and emericella nidulans. it was not incorporated in the case of the facultative anaerobic microorganisms escherichia coli and enterobacter aerogenes, which, however, did incorporate the nitrogen atom of tyrosine. these results show that aerobic microorganisms and facultative anaerobic m ...19873566774
complete amino-acid sequence of a functional unit from a molluscan hemocyanin (helix pomatia).from the beta c-hemocyanin (beta c-hc) of the vineyard snail, helix pomatia, the functional unit d (mr approximately equal to 50,000-55,000) was isolated by limited proteolysis and gel chromatography. a small quantity of functional unit d was obtained intact, but the major part in the form of two peptides (mr approximately equal to 43,000 and 10,000, respectively) connected by a disulfide bridge. after reduction and carboxymethylation, these were separated from each other and cleaved by conventi ...19873620107
a long polypyrimidine/polypurine tract induces an altered dna conformation on the 3' coding region of the adjacent myosin heavy chain gene.a long (147 base pairs), natural a.t rich polypyrimidine/polypurine tract has been found 55 base pairs downstream of a chicken embryonic myosin heavy chain (mhc) gene. analysis at the nucleotide level of nicks induced by s1 and neurospora crassa nucleases indicate that this long interrupted polypyrimidine/polypurine tract exists in an alternate dna structure in vitro at ph 4.5 and ph 7.5 in both supercoiled and linear plasmid dna. the polypyrimidine/polypurine tract induces this alternate struct ...19873671071
extraction and purification of molybdenum cofactor from milk xanthine oxidase.molybdenum cofactor (mocofactor) is extracted efficiently, free of impurities and in high concentrations, by acid treatment of xanthine oxidase and subsequent incubation of the precipitate with phosphate buffer containing edta, molybdate and oxygen. it is suggested that cofactor is bound to the enzyme via hydrophobic forces as well as via an oxygen-sensitive mechanism. upon extraction, the capability to complement the apo nitrate reductase of neurospora crassa nit-1 can be conserved only in the ...19873691496
mitochondrial binding of a protein affected in mutants resistant to the microtubule inhibitor podophyllotoxin.specific antibodies to a protein p1 mr approximately equal to 63,000) from chinese hamster ovary cells, which is affected in mutants resistant to the microtubule inhibitor, podophyllotoxin, and behaves like a microtubule-related protein by certain criteria [14], have been raised. the antibody reacts specifically with the p1 protein in one- and two-dimensional immunoblots, and a cross-reacting protein of similar molecular mass and electrophoretic mobility is also found in cells from various verte ...19873319627
cloning, mapping and molecular analysis of the pyrg (orotidine-5'-phosphate decarboxylase) gene of aspergillus nidulans.we have modified the transformation procedures of ballance et al. [biochem. biophys. res. commun. 112 (1983) 284-289] to give increased rates of transformation in aspergillus nidulans. with the modified procedures we have been able to complement pyrg89, a mutation in the orotidine-5'-phosphate decarboxylase gene of a. nidulans, by transformation with a library of wild-type (wt) sequences in pbr329. we have recovered, by marker rescue from one such transformant, a plasmid (pjr15) that carries an ...19873328733
the primary structure of cytochrome c1 from neurospora crassa.the primary structure of the cytochrome c1 subunit of ubiquinol-cytochrome-c reductase from mitochondria of neurospora crassa was determined by sequencing the cdna of a bank cloned in escherichia coli. from the coding region the sequence of 332 amino acids, corresponding to the molecular mass of 36,496 da, was derived for the precursor protein. the mature protein, the n terminus of which was previously sequenced [tsugita et al. (1979) in cytochrome oxidase (king, t. e. et al., eds) pp. 67-77, el ...19873030747
molecular cloning of a cdna for a human adp/atp carrier which is growth-regulated.we have identified in a human cdna library a clone (hp2f1) whose cognate rna is growth-regulated. the insert has been sequenced and the nucleotide sequence shows a strong homology to the nucleotide sequences of the adp/atp carrier cdna and gene, respectively, isolated from neurospora crassa and saccharomyces cerevisiae. the putative amino acid sequence of hp2f1 shows an 87% homology to the amino acid sequence of the adp/atp carrier from beef heart mitochondria. we conclude that the insert of hp2 ...19873031073
structure and expression of the overlapping nd4l and nd5 genes of neurospora crassa mitochondria.genes homologous to the mammalian mitochondrial nadh dehydrogenase subunit genes nd4l and nd5 were identified in the mitochondrial genome of the filamentous fungus neurospora crassa, and the structure and expression of these genes was examined. the nd4l gene (interrupted by one intervening sequence) potentially encodes an 89 residue long hydrophobic protein that shares about 26% homology (or 41% homology if conservative amino acid substitutions are allowed) with the analogous human mitochondrial ...19873035337
isolation and characterization of the nuclear gene encoding the rieske iron-sulfur protein (rip1) from saccharomyces cerevisiae.the nuclear gene encoding the rieske iron-sulfur protein of the cytochrome bc1 complex of the mitochondrial respiratory chain has been isolated and characterized from saccharomyces cerevisiae. we used a segment of the iron-sulfur protein gene from neurospora crassa (harnisch, u., weiss, h., and sebald, w. (1985) eur. j. biochem. 149, 95-99) to detect the yeast gene by southern analysis. five different but overlapping clones were then isolated by probing a yeast genomic library carried on yep 13 ...19873036836
regulation of synthesis and secretion of acid and alkaline phosphatases in neurospora crassa.we show that n. crassa represses the production of acid phosphatase at ph higher than 8.0, irrespective of the carbon source used, whereas production was stimulated by sucrose at slightly acidic ph. the same profile of acid phosphatase production was observed in the pho-2a, pho-3a, nuc-1a, nuc-2a and pregc mutant strains. we also show that acid phosphatase synthesized by the pregc mutant strain grown on high phosphate medium has pronounced differences when compared to the enzyme synthesized by t ...19872967123
gamma-ray-sensitive mutants of neurospora crassa with characteristics analogous to ataxia telangiectasia cell lines.well characterized gamma-ray sensitive mutants of the fungus neurospora crassa have been screened for characteristics analogous to those of cell lines derived from humans with the genetic disease, ataxia telangiectasia (at). two neurospora mutants, uvs-6 and mus-9, show the at cell line characteristics of gamma-ray and bleomycin sensitivity, and little or no repression of dna synthesis following treatment with these agents. normal human or neurospora cells show an extensive biphasic dna synthesi ...19872434849
particular rna primer from growth medium differentially stimulates in vitro dna synthesis and in vivo cell growth of neurospora crassa and its slime mutant.purine rich small "rna-primer" molecules (about 10-12 nucleotides), secreted into the growth medium of 3-h germinated conidia of n. crassa, strongly stimulated a concentration-dependent in vitro dna synthesis of n. crassa slime mutant as well as dnas from the human cancer cells but did not affect that from normal cells. these "rna-primer" molecules stimulated also in vivo cell growth of n. crassa slime mutant, but not of the n. crassa wild type. our studies suggest that dnas from the slime mutan ...19872452704
the molybdenum iron-sulphur protein from desulfovibrio gigas as a form of aldehyde oxidase.the molybdenum iron-sulphur protein originally isolated from desulfovibrio gigas by moura, xavier, bruschi, le gall, hall & cammack [(1976) biochem. biophys. res. commun. 72, 782-789] has been further investigated by e.p.r. spectroscopy of molybdenum(v). the signal obtained on extended reduction of the protein with sodium dithionite has been shown, by studies at 9 and 35 hgz in 1h2o and 2h2o and computer simulations, to have parameters corresponding to those of the slow signal from the inactive ...19872821990
purification and characterization of an endo-exonuclease from saccharomyces cerevisiae that is influenced by the rad52 gene.an endo-exonuclease has been purified from logarithmically growing cells of the yeast saccharomyces cerevisiae. identification and purification of this nuclease was facilitated by its being precipitable with an antibody raised against a previously described neurospora crassa endo-exonuclease (resnick, m. a., chow, t. y.-k. nitiss, j., and game, j. c. (1984) cold spring harbor symp. quant. biol. 49, 639-649 and t. y.-k. chow and m. a. resnick (1988) mol. gen. genet., in press). the enzyme which w ...19872826428
nitrobacter winogradskyi cytochrome a1c1 is an iron-sulfur molybdoenzyme having hemes a and c.cytochrome a1c1 (nitrite-cytochrome c oxidoreductase) purified from nitrobacter winogradskyi (formerly n. agilis) contained molybdenum, non-heme iron, and acid-labile sulfur in addition to hemes a and c; it contained 1 mol of heme a, 4-5 g atoms of non-heme iron, 2-5 g atoms of acid-labile sulfur, and 1-2 g atoms of molybdenum per mol of heme c, but did not contain copper. the fluorescence spectra of the molybdenum cofactor derivative prepared from cytochrome a1c1 were very similar to those of t ...19872828343
control of nucleotide and erythroascorbic acid pools by cyclic amp in neurospora crassa.udpglucuronic acid and erythroascorbic acid were identified in extracts of the fungus neurospora crassa. the concentrations of these two compounds are estimated, in growing wild type n. crassa, to be about 0.10 and 0.28 mumol/ml of cell water, respectively. the pools of these two compounds are regulated by cyclic amp in neurospora, both being elevated in the cr-1, adenylate cyclase deficient mutant and both being lowered by exogenous cyclic amp. the pools of these two compounds are also elevated ...19872825802
rearrangement of duplicated dna in specialized cells of neurospora.introduction of dna into neurospora crassa can lead to sequence instability in the sexual phase of the life cycle. sequence instability was investigated by using a set of strains transformed with single copies of a plasmid including host sequences, neurospora sequences deleted from the host genome, and foreign sequences. the sequences already represented in the host were rearranged at high frequency in a cross. in general, both elements of the duplication, that from the plasmid and that from the ...19872960455
molecular cloning and analysis of the regulation of nit-3, the structural gene for nitrate reductase in neurospora crassa.the nit-3 gene of neurospora crassa encodes the enzyme nitrate reductase and is regulated by nitrogen catabolite repression and by specific induction with nitrate. the nit-3 gene was isolated from a cosmid-based genomic library by dual selection for benomyl resistance and for the ability to complement a nit-3 mutant strain using the sibling-selection procedure. the nit-3 gene was subcloned as a 3.8-kilobase dna fragment from a cosmid that carried an approximately 40-kilobase n. crassa dna insert ...19872891138
relationship between two major immunoreactive forms of arginase in neurospora crassa.two major immunoreactive proteins of mr 41,700 and 36,100 have been detected in crude mycelial extracts with polyclonal antibodies raised against arginase purified from neurospora crassa. the latter corresponded to the protein used to obtain the antibodies. both polypeptides were either missing or present in very low amounts in mutant strains having little or no detectable arginase activity. the relative proportion of the two species was altered in strains containing the nitrogen catabolite regu ...19872890621
circadian rhythms in neurospora crassa: a clock mutant, prd-1, is altered in membrane fatty acid composition.the fatty acid compositions of the phospholipids of neurospora crassa mutants with altered periods were determined to test the possibility that some of these mutants might have altered membrane composition. in liquid shaker culture in constant light the bd (band) strain, which has a normal period (21.6 h), exhibited a growth-dependent increase in linoleic acid content and a decrease in linolenic acid content during early log phase growth. by late log phase, fatty acid composition was essentially ...19872889471
antibiotic-induced derepression of the nad-specific glutamate dehydrogenase of neurospora crassa.the catabolic, nad-specific glutamate dehydrogenase (nad-gdh) of neurospora crassa is under carbon catabolite repression. cells grown on a glycolytic carbon source, such as sucrose, have low basal levels of enzyme activity. treatment of repressed cells with either polymyxin b or amphotericin b resulted in derepression of nad-gdh. derepression at the transcriptional level occurred very rapidly (within 30 min) in response to polymyxin b addition but reached a plateau within 2 h. amphotericin b-ind ...19872822659
carboxyl-terminal sequences influence the import of mitochondrial protein precursors in vivo.the large subunit of carbamoyl phosphate synthase a [carbon-dioxide: l-glutamine amido-ligase (adp-forming, carbamate-phosphorylating), ec 6.3.5.5] from neurospora crassa is encoded by a nuclear gene but is localized in the mitochondrial matrix. we have utilized n. crassa strains that produce both normal and carboxyl-terminal-truncated forms of carbamoyl phosphate synthase a to ask whether the carboxyl terminus affects import of the carbamoyl phosphate synthase a precursor. we found that carboxy ...19872958846
characterization of pi-repressible enzymes secreted in culture media by neurospora crassa wild-type cells and null-type mutants.in wild-type mycelial cultures of neurospora crassa under pi-limited conditions, alkaline phosphatase, cyclic phosphodiesterases i, ii, iii, and iv, 5'-nucleotidase, acid and alkaline nucleases, rnase n1, and a newly detected endonuclease were secreted into the culture media. these enzymes were either not produced or were produced in very reduced levels in mutants nuc-1, -2, -3, -4, -5, -6, and -7 and cpd-4. the proteins were examined by polyacrylamide gel electrophoresis in a manner which allow ...19872820943
heat shock induces peroxidase activity in neurospora crassa and confers tolerance toward oxidative stress.heat shock treatment of 14-h-old neurospora crassa mycelium, for 1 h at 48 degrees c, led to the induction of high levels of peroxidase (ec. 1.11.1.7) activity. no significant change was observed in the superoxide dismutase content. colonies formed by plating conidial suspensions on sorbose-medium also exhibited high peroxidase activity following exposure to hyperthermia and were found to be resistant to normally toxic doses of h2o2. thus one of the heat shock proteins of n. crassa has the funct ...19872959286
a eukaryotic repressor protein, the qa-1s gene product of neurospora crassa, is homologous to part of the arom multifunctional enzyme.little is known about the proteins involved in the control of gene expression in eukaryotes. although some of these proteins have been sequenced, their biochemical functions are not well understood and the identification of homologies to proteins of known activities may give useful clues to the functions of these regulatory proteins. we report here that the qa-1s repressor protein of the fungus neurospora crassa is strongly homologous to the pentafunctional arom enzyme found in many lower eukary ...19872960822
a novel stimulator of protein phosphorylation in neurospora crassa.an endogenous thermostable activator of protein kinase iii (pkiii) was purified from 100,000 x g supernatants of neurospora crassa mycelial extracts. this 38,000 dalton polypeptide, clearly separable from calmodulin on p-60 gel filtration, specifically stimulated n. crassa pkiii activity on casein or phosvitin "in vitro" phosphorylation. the factor was only present in the initial growth phase of the fungus. the mechanism of pkiii activation and its possible regulatory role are discussed.19872961977
two developmental stages of neurospora crassa utilize similar mechanisms for responding to heat shock but contrasting mechanisms for recovery.at the heat shock temperature of 45 degrees c, there is a transient induction of the synthesis of heat shock proteins and repression of normal protein synthesis in cells of neurospora crassa. both conidiospores and mycelial cells resume normal protein synthesis after 60 min at high temperature. at the rna level, however, these two developmental stages responded with different kinetics to elevated temperature. heat shock rnas (for hsp30 and hsp83) accumulated and declined more rapidly in spores t ...19872959857
isolation of telomere dna from neurospora crassa.the most distal known gene on neurospora crassa linkage group vr, his-6, was cloned. a genomic walk resulted in isolation of the telomere at vr. it was obtained from a library in which the endmost nucleotides of the chromosome had not been removed by nuclease treatment before being cloned, and mapping indicates that the entire chromosome end has probably been cloned. sequences homologous to the terminal 2.5 kilobases of dna from vr from these oak ridge n. crassa strains are found at other sites ...19872890097
transcription of neurospora crassa 5 s rrna genes requires a tata box and three internal elements.the sequences required for transcription of neurospora crassa 5s rrna genes have been defined using a comprehensive set of deletion and substitution mutations introduced into two cloned genes. an upstream tata box (consensus tcataga) located at -29 to -24, and three internal regions (d, a and c) localized to +19 to +30, +44 to +57 and +73 to +103, respectively, are absolutely required for transcription in vitro. the tata box fixes the start point of transcription. the a and c regions correspond ...19872960818
partial characterization of gtp-binding proteins in neurospora.six fractions of gtp-binding proteins separated by gel filtration of a mycelial extract containing membrane components of neurospora crassa were partially characterized. [35s]gtp gamma s bound to gtp-binding protein was assayed by repeated treatments with a norit solution and centrifugation. the binding of [35s]gtp gamma s to gtp-binding proteins was competitively prevented in the presence of 0.1 to 1 mm gtp but not in the presence of atp. these gtp-binding proteins fractionated by the gel colum ...19872956953
electron microscopy and image analysis of the mitochondrial outer membrane channel, vdac.the channel protein in the outer membrane of neurospora crassa mitochondria, vdac, forms extended planar crystals on the membrane. the arrays, which are induced by phospholipase a2, are polymorphic, varying from parallelogram (p) to near-rectangular (r) geometry with increased phospholipase treatment. computer-based analysis of projection images of negatively stained vdac arrays indicates that the protein forms a transmembrane channel in the p array. comparison of average images of arrays embedd ...19872442147
a protein required for splicing group i introns in neurospora mitochondria is mitochondrial tyrosyl-trna synthetase or a derivative thereof.the nuclear cyt-18 mutants of neurospora crassa are defective in splicing a number of group i introns in mitochondria. here, cloning and sequencing of the cyt-18 gene show that it contains an open reading frame having significant homology to bacterial tyrosyl-trna synthetases. biochemical and genetic experiments lead to the conclusions that the cyt-18 gene encodes mitochondrial tyrosyl-trna synthetase, that mutations in this gene inhibit splicing directly, and that mitochondrial tyrosyl-trna syn ...19873607872
the influence of copper on the induction of tyrosinase and laccase in neurospora crassa.the influence of copper on the cycloheximide-induced synthesis of the copper-containing enzymes tyrosinase and laccase in neurospora crassa was studied by enzyme activity measurements and immunological means. the amount of active enzyme molecules is far higher when the culture medium is copper-supplemented before cycloheximide induction. the synthesis of the apoproteins is not dependent on the presence of copper. this suggests the existence of a copper-storage protein for which metallothionein i ...19872956123
copper accumulation in the cell-wall-deficient slime variant of neurospora crassa. comparison with a wild-type strain.the copper-uptake process in the cell-wall-deficient slime variant of the fungus neurospora crassa was compared with that in a wild-type strain. in both organisms investigated most of the copper is taken up from the culture medium during the exponential growth period. the wild-type strain, however, accumulates much more copper than does the slime variant. the influence of the copper concentration in the culture medium on the amounts of copper accumulated intracellularly suggests separate ways of ...19872959274
isolation and characterization of non-neuronal enolase (nne) from neurospora crassa and comparison with neuron specific enolase isolated from neuroblastoma cell line ng108.enolase is a vital enzyme of the glycolytic pathway. it exists mainly in two forms, non-neuronal enolase (nne) and neuron specific enolase (nse). neurospora crassa, a filamentous fungus, was used as the source of pure nne, and by using deae-cellulose and a sephadex g-150 column chromatography highly purified enzyme (20.4 fold purification with 54.7 percent recovery) was obtained. the development profile of the enzyme shows a peak value after 90 hours of mycelial growth from conidia of n. crassa. ...19872969242
regulation of carbon and nitrogen flow by glutamate synthase in neurospora crassa.a glycine-resistant neurospora crassa mutant (am-132;glyr), derived from the am-132 mutant, was isolated and characterized. [am-132 itself has a deletion in the structural gene for nadp-dependent glutamate dehydrogenase (gdh).] this new mutation also conferred resistance to serine and methionine sulphoximine (ms), which are inhibitors of glutamine synthetase (gs). in addition, the mutant obtained grew better on ammonium than the am-132 parental strain. resistance to glycine was not due to increa ...19872959749
molecular cloning and characterization of the cys-3 regulatory gene of neurospora crassa.the regulatory gene cys-3+ controls the synthesis of a number of enzymes involved in sulfur metabolism. cys-3 mutants show a multiple loss of enzymes in different pathways of sulfur metabolism. the cys-3+ gene was isolated by transformation of an aro-9 qa-2 cys-3 inl strain with a clone bank followed by screening with the "sib selection" method. the library used (pral1) contained inserts of sau3a partial digest fragments of about 9 kilobases as well as the neurospora qa-2+ gene. double selection ...19872886908
deficiency in mrna splicing in a cytochrome c mutant of neurospora crassa: importance of carboxy terminus for import of apocytochrome c into mitochondria.molecular cloning and characterization of cytochrome c cdna clones of neurospora crassa wild-type (74a) and a cytochrome c-deficient mutant (cyc1-1) are described. southern blot analysis of genomic dna indicates that only one cytochrome c gene exists in the n. crassa genome. the cdna sequence of the wild-type cytochrome c confirmed the previously determined protein sequence. sequence analysis of the cyc1-1 cdna for cytochrome c revealed the presence of a larger open reading frame, owing to the p ...19872820723
differential dna methylation during the vegetative life cycle of neurospora crassa.isotope dilution gas chromatography-mass spectrometry analysis of genomic dnas isolated from the different growth phases of neurospora crassa revealed significant differences in the amounts of 5-methylcytosine; the mol % of 5-methylcytosine was 0.36 in conidia (asexual spores), 0.40 in conidial germlings cultured for 3 h, 0.24 in mycelial cells that had grown exponentially for 6 and 12 h, and 0.40 in stationary-phase mycelial cells. these results indicate an approximate inverse correlation betwe ...19872953709
arginine-specific carbamoyl phosphate metabolism in mitochondria of neurospora crassa. channeling and control by arginine.citrulline is synthesized in mitochondria of neurospora crassa from ornithine and carbamoyl phosphate. in mycelia grown in minimal medium, carbamoyl phosphate limits citrulline (and arginine) synthesis. addition of arginine to such cultures reduces the availability of intramitochondrial ornithine, and ornithine then limits citrulline synthesis. we have found that for some time after addition of excess arginine, carbamoyl phosphate synthesis continued. very little of this carbamoyl phosphate esca ...19872953716
characterization of nit-2, the major nitrogen regulatory gene of neurospora crassa.the nit-2 gene is the major nitrogen-regulatory gene of neurospora crassa, and under conditions of nitrogen limitations, it turns on the expression of various unlinked structural genes which specify nitrogen-catabolic enzymes. the nit-2 gene was subcloned as a 6-kilobase (kb) dna fragment from a cosmid that carried approximately a 40-kb n. crassa dna insert. the nit-2 gene was localized in a dna segment of approximately 3.5 kb and was shown to correspond to a unique dna sequence located on linka ...19872885741
a single precursor protein for two separable mitochondrial enzymes in neurospora crassa.the arg-6 locus of neurospora crassa encodes two early enzymes of the arginine biosynthetic pathway, acetylglutamate kinase and acetylglutamyl-phosphate reductase. previous genetic and biochemical analyses of this locus and its products showed that: 1) strains carrying polar nonsense mutations in the acetylglutamate kinase gene lacked both enzyme activities (davis, r.h., and weiss, r.l. (1983) mol. gen. genet. 192, 46-50), and 2) the proteins isolated from mitochondria were completely separable ...19873032945
gmp-stimulation of the cyanide-insensitive mitochondrial respiration in heat-shocked conidia of neurospora crassa.in mitochondria of heat-shocked conidia of neurospora exogenous nadh and succinate were oxidized mainly via the alternative, hydroxamate-sensitive pathway (70%) and only 30% via the cytochromic, cyanide-sensitive pathway which was predominant in untreated conidia; the alternative oxidase pathway was markedly stimulated by guanosine 5'-monophosphate (gmp).19873032673
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