TitleAbstractYear(sorted ascending)
inheritance of dna-induced inositol independence of inositolless neurospora crassa.neurospora crassa (n. crassa) inositolless (inl) strain gives inositol-independent colonies (inl+) if treated with dna from wild type n. crassa. there is an increased number of unusual non-mendelian tetrads (24%) among the progeny. in sexual crosses of these strains with inl alleles ascospores of complete ordered tetrads were isolated. clones of these aberrant tetrads were examined for the inheritance of the inl+ and inl markers respectively. several inl+ clones of single ascospores of these tet ...19806452779
mutation-induction in repair-deficient strains of neurospora.various mutants sensitive to uv-induced inactivation have been used to study the process of spontaneous and induced mutation in the ad-3 region of neurospora crassa. studies on haploid strains have shown that the process of mutation-induction in the ad-3 region is under genetic control. studies on two-component heterokaryons have shown that this control effects both point mutations and multilocus deletions. comparisons made between an excision-repair deficient two-component heterokaryon (59) hav ...19806452121
mutagen-sensitive mutants in neurospora.initial work on the fungus neurospora crassa has shown that a least two dna-repair systems exist in this eukaryote: excision repair and a mutation-prone repair. the evidence suggests that there is also a third repair system. recently, new mutagen-sensitive strains have been isolated in several laboratories, but they are not yet fully characterized. a hunt for cytoplasmically inherited uv sensitivity has failed to turn up any such mutants among 25 new uv-sensitive isolates.19806452119
effects of cytochalasins on neurospora crassa. i. growth and ultrastructure. 19806447315
control of arginine metabolism in neurospora: flux through the biosynthetic pathway.the flux into the arginine biosynthetic pathway of neurospora crassa was investigated using a mutant strain lacking the ornithine-degrading enzyme ornithine aminotransferase (ec flux was measured by the increase in the sum of the radioactivity (derived from [14c]glutamic acid) in the ornithine pool, the arginine pool, and arginine incorporated into proteins. complete cessation of flux occurred immediately upon the addition of arginine to the growth medium. this response occurred prior ...19806444407
effect of carbon source on enzymes and metabolites of arginine metabolism in neurospora.the levels of enzymes and metabolites of arginine metabolism were determined in exponential cultures of neurospora crassa grown on various carbon sources. the carbon sources decreased in effectiveness (as determined by generation times) in the following order: sucrose, acetate, glycerol, and ethanol. the basal and induced levels of the catabolic enzymes, arginase (ec and ornithine transaminase (ec, were lower in mycelia grown on poor carbon sources. arginase was more sensitive ...19806444405
carbamyl phosphate synthetase a of neurospora crassa.carbamyl phosphate synthetase a of neurospora crassa was partially purified from mitochondrial extracts. it is an extremely unstable enzyme (t 1/2 = 45 min at 25 detrees c) made up of two unequal subunits. the native enzyme has a molecular weight of approximately 175,000, and the large subunit has a molecular weight of about 125,000. both the native enzyme and its large subunit are quite asymmetric, as revealed by slow sedimentation in sucrose gradents (7.3s and 6.6s, respectively). the small su ...19806243618
an enzymatic alteration secondary to adenylyl cyclase deficiency in the cr-1 (crisp) mutant of neurospora crassa: nicotinamide adenine dinucleotide (phosphate) glycohydrolase overproduction. 19806243107
purification and properties of neurospora crassa endo-exonuclease, an enzyme which can be converted to a single-strand specific endonuclease. 19806154864
the role fo glutamine synthetase and glutamine metabolism in nitrogen metabolite repression, a regulatory phenomenon in the lower eukaryote neurospora crassa.growth of neurospora crassa on media containing nh4+ leads to the repression of a variety of permeases and alternative pathways which would generate nh4+, so called "ammonium repression." the mutant am2 which lacks nadp-gdh is not subject to ammonium repression of nitrate reductase or urea permease, but like the wild type has repressed levels of these systems when grown in the presence of proline, glutamate or glutamine. the glutamine synthetase (gs) mutant gln-1a has derepressed levels of the a ...19806109228
[the mechanism of action of the herbicide n-(phosphonomethyl)glycine: its effect on the growth and the enzymes of aromatic amino acid biosynthesis in escherichia coli (author's transl)].n-(phosphonomethyl) glycine prolongates the lag-phase and inhibits the growth rate of escherichia coli, salmonella typhimurium and pseudomonas aureofaciens. the eucaryotes saccharomyces cerevisiae and neurospora crassa are not inhibited. the effect of growth inhibition in an e. coli culture depends on the time of the herbicide addition and no cells showing resistance against it are observed. the inhibitory effect can be overcome completely by a mixture of phenylalanine, tyrosine and tryptophan. ...19806105996
enzymatic trimethylation of residue-72 lysine in cytochrome c. effect on the total structure.a highly purified protein methylase iii from neurospora crassa or saccharomyces cerevisiae specifically methylates a single lysine residue of position 72 of horse heart cytochrome c. the enzymatically methylated cytochrome c has been separated from the unmethylated counterpart species by isoelectric focusing. simultaneously, the pi values of these two species were found to be 9.49 and 10.03, respectively. since methyl substitution increases the basicity associated with the epsilon-amino group of ...19806244857
physical map of aspergillus nidulans mitochondrial genes coding for ribosomal rna: an intervening sequence in the large rrna cistron.a detailed map of the 32 kb mitochondrial genome of aspergillus nidulans has been obtained by locating the cleavage sites for restriction endonucleases pst i, bam h i, hha i, pvu ii, hpa ii and hae iii relative to the previously determined sites for eco r i, hind ii and hind iii. the genes for the small and large ribosomal subunit rnas were mapped by gel transfer hybridization of in vitro labelled rrna to restriction fragments of mitochondrial dna and its cloned eco r i fragment e3, and by elect ...19806246396
distribution of sequences common to the 25--28s-ribonucleic acid genes of xenopus laevis and neurospora crassa.the extent of homology between the nucleotide sequence of l-rrna (the major rna component of the larger ribosomal subparticle) of a lower eukaryote (neurospora crassa) and an amphibian (xenopus laevis) was investigated by utilizing rdna (dna coding for rrna) of x. laevis cloned in plasmids pmb9 and pml2, and rdna of n. crassa cloned in bacteriophage lambda. hybridization studies revealed that sequences common to both n. crassa and x. laevis l-rrna comprise a total of approx. 1050 /+- 200 nucleot ...19806250536
inhibition of udp-n-acetylglucosamine pyrophosphorylase by uridine.udp-n-acetylglucosamine pyrophosphorylases (utp: 2-acetamido-2-deoxy-alpha-d-glucose-1-phosphate uridylyltransferase, ec from baker's yeast and neurospora crassa ifo 6178 were inhibited by uridine which is the nucleoside moiety of udp-glcnac. the inhibition was shown in both directions of pyrophosphorolysis and of synthesis of udp-glcnac. kinetic analysis revealed that uridine demonstrated a noncompetitive type of inhibition with udp-glcnac and competitive inhibition with ppi. the ki v ...19806250624
assembly of the mitochondrial membrane system. sequences of yeast mitochondrial trna genes.two cytoplasmic "petite" (rho-) clones of saccharomyces cerevisiae have been selected for the retention of the aspartic acid trna gene. the two clones, designated ds200/a102 and ds200/a5, have tandemly repeated segments of mitochondrial dna (mtdna) with unit lengths of 1,000 and 6,400 base pairs, respectively. the ds200/a102 genome has a single trna gene with a 3'-cug-5' anticodon capable of recognizing the 5'-gac-3' and 5'-gau-3' codons for aspartic acid. the mtdna segment of ds200/a102 has bee ...19806251074
mapping of mitochondrial structural genes in neurospora crassa.a hybridization method has been employed to study the organization of the mitochondrial genome of neurospora crassa. the method involves the use of 5' end-labeled single-stranded restriction fragments obtained from cytoplasmic "petite" strains of saccharomyces cerevisiae known to contain single mitochondrial genes. the presence and localization of genes homologous to subunits 1, 2, and 3 of cytochrome oxidase, cytochrome b and subunit 6 of the atpase is thus established for the mitochondrial gen ...19806253481
n,n'-dicyclohexylcarbodiimide binds specifically to a single glutamyl residue of the proteolipid subunit of the mitochondrial adenosinetriphosphatases from neurospora crassa and saccharomyces cerevisiae.the n,n'-dicyclohexylcarbodiimide-binding proteolipid subunit of the mitochondrial adenosinetriphosphatases (atp phosphohydrolase, ec of neurospora crassa and saccharomyces cerevisiae were purified from mitochondria incubated with the radioactively labeled inhibitor. the specifically labeled subunit was cleaved with cyanogen bromide and n-bromosuccinimide, and the resultant fragments were separated by gel chromatography in the presence of 80% (vol/vol) formic acid. the n,n'-dicyclohexyl ...19806444724
the hexokinases from wild-type and morphological mutant strains of neurospora crassa. 19806444874
3-amino-1,2,4-triazole is an inhibitor of protein synthesis on mitoribosomes in neurospora crassa.the effects of the herbicide, 3-amino-1,2,4-triazole, an inhibitor of heme synthesis in rat liver, have been examined in the mold neurospora crassa. the drug is a potent inhibitor of the growth of the mold and produces biochemical changes identical to those produced by chloramphenicol. 3-amino-1,2,4-triazole, like chloramphenicol, is a direct and specific inhibitor of protein synthesis on mitoribosomes. a decrease in the levels of mitochondrial proteins which are completely or partly made on mit ...19806445208
effects of ph on the mutagenicity of sodium azide in neurospora crassa and salmonella typhimurium.sodium azide at various ph values did not cause a significant increase in the frequency of forward mutation above the control frequency at the adenine-3 (ad-3) region in resting conidia and in conidia from growing cultures of heterokaryons 12 and 59 of neurospora crassa. conidia from ad-3 mutants were plated with sodium azide at various ph values, and no obvious increase in reverse mutation above the controls was observed. data are presented showing that sodium azide at ph 3 is inactivating coni ...19806445502
mutagenic activity of tetryl, a nitroaromatic explosive, in three microbial test systems.the military explosive n-methyl-n,2,4,6-tetranitroaniline (tetryl) is a direct acting mutagen in three microbial mutagenicity test systems at concentrations as low as 5 microgram/ml. in two of these systems (neurospora crassa and salmonella typhimurium) it caused base-pair substitution reversions. in the third (saccharomyces cerevisiae d4) it caused mitotic gene conversions at two loci. three nonaromatic explosives (petn, rdx, hmx) did not exhibit mutagenic activity in the ames salmonella test. ...19806445609
the extraction of inositol-containing phospholipids and phosphatidylcholine from saccharomyces cerevisiae and neurospora use of fungi grown in the presence of [3h]-inositol and [14c]choline, we have explored methods for the quantitative extraction of inositol-containing phospholipids and phosphatidylcholine. slightly alkaline mixtures of both ethanol-water and ethanol-diethylether-water at elevated temperatures were shown to effectively extract these lipids from intact saccharomyces cerevisiae and neurospora crassa. some previously published procedures fail to completely extract to very polar phosphoinositol-co ...19806445928
[influence of cultivation temperature on the development of functionally active photoregulatory systems in cells of neurospora crassa and physarum polycephalum].illumination with a visible light is known to induce accumulation of colored carotenoid pigments in mycelial cells on neurospora crassa and sporulation of starved macroplasmodia of physarum polycephalum. in both microorganisms, the temperature, at which they are cultivated in the dark, controls manifestation of the photoregulation processes in the cells subsequently exposed to light. the maximal rate of photoinduced accumulation of carotenoids in n. crassa is observed, when the cells are grown i ...19806446087
mutagenesis at the ad-3a and ad-3b loci in haploid uv-sensitive strains of neurospora crassa. i. development of isogenic strains and spontaneous mutability.7 different mutations that confer sensitivity to inactivation by ultraviolet light have been investigated for their effect on spontaneous mutation at the ad-3a and ad-3b loci in haploid strains of neurospora crassa. the collection and development of strains isogenic to wild-type 74a is described as well as experiments to determine the effects of each mutation on the spontaneous ad-3 mutation frequency. 6 of the strains showed spontaneous ad-3 mutant frequencies not significantly different from t ...19806446681
mutagenesis at the ad-3a and ad-3b loci in haploid uv-sensitive strains of neurospora crassa. ii. comparison of dose-response curves for inactivation and mutation induced by uv.uv-induced inactivation and induction of mutations at the ad-3a and ad-3b loci of neurospora crassa have been compared among 7 different uv-sensitive strains and a standard wild-type strain. the 7 strains show varying degrees of sensitivity to uv-induced inactivation, with the relative sensitivity being: uvs-2 greater than uvs-3 greater than uvs-4 greater than uvs-6 greater than upr-1 greater uvs-5 greater than uvs-1. studies on the induction of ad-3 mutants by uv show that the 2 excision-repair ...19806446682
protein synthesis by hybrid ribosomes reconstructed from rabbit reticulocyte ribosomal core-particles and amphibian or fungal was shown that high-salt (2.75 m-nh4cl/69mm-mgcl2) shock treatment at 0 degrees c of the larger subparticles (l-subparticles) of rabbit, xenopus laevis and neurospora crassa cytoplasmic ribosomes yielded split-protein fractions that were not only functionally equivalent but also interchangeable. thus, although the remaining core-particles were inactive in both the puromycin reaction and in poly(u)-directed polyphenylalanine synthesis, activity was restored when they were combined with either ...19806446904
secondary structure predictions for the nad-specific glutamate dehydrogenase of neurospora crassa.from the amino acid sequences of the three known fragments of the nad-specific glutamate dehydrogenase of neurospora crassa, the secondary structures have been predicted from the rules of chou and fasman (chou, p.y., and fasman, g.d. (1979) biophys. j. 26, 367-384). comparison of these structures with those calculated for bovine glutamate dehydrogenase has shown that in the regions of homologous sequences containing identified functional regions, there is considerable homology of structure. from ...19806447152
novel features in the genetic code and codon reading patterns in neurospora crassa mitochondria based on sequences of six mitochondrial trnas.we report the sequences of neurospora crassa mitochondrial alanine, leucine(1), leucine(2), threonine, tryptophan, and valine trnas. on the basis of the anticodon sequences of these trnas and of a glutamine trna, whose sequence analysis is nearly complete, we infer the following: (i) the n. crassa mitochondrial trna species for alanine, leucine(2), threonine, and valine, amino acids that belong to four-codon families (gcn, cun, acn, and gun, respectively; n = u, c, a, or g) all contain an unmodi ...19806447871
eukaryotic dna segments capable of autonomous replication in yeast.a selective scheme is presented for isolating sequences capable of replicating autonomously in the yeast saccharomyces cerevisiae. yip5, a vector that contains the yeast gene ura3, does not transform a ura3 deletion mutant to ura+. hybrid yip5-escherichia coli dna molecules also fail to produce transformants. however, collections of molecular hybrids between yip5 and dna from any of six eukaryotes tested (s. cerevisiae, neurospora crassa, dictyostelium discoideum ceanhorabditis elegans, drosophi ...19806449009
the isolation and characterization of mutants defective in nitrate assimilation in neurospora crassa.the isolation and characterization of mutants altered for nitrate assimilation in neurospora crassa is described. the mutants isolated can be subdivided into five classes on the basis of growth test that correspond to the growth patterns of existing mutants at six distinct loci. mutants with growth characteristics like those of nit-2, nit-3 and nit-6 are assigned to those loci on the basis of noncomplementation and lack of recombination. mutants that, from their growth patterns, appear to lack t ...19806449399
the nucleotide sequence of phenylalanine trna from the cytoplasm of neurospora crassa.the phenylalanine trna from the cytoplasm of neurospora crassa has been purified and sequenced. the sequence is: pgcggguuuam2gcuca (n) gddgggagagcm22gpsicagacmugmaayapsim5cugaagm7gdm5cgugugtpsicgm1auccacacaaaccgcaccaoh. both in the nature of modified nucleotides which are present in this trna and in the overall sequence, this trna resembles more closely phenylalanine trnas of eukaryotic cytoplasm than those of prokaryotes. the sequence of this trna differs from those of the corresponding trnas o ...19806449691
a phenylalanine trna gene from neurospora crassa: conservation of secondary structure involving an intervening sequence.we have isolated and sequenced a trnaphe gene from neurospora crassa. hybridization analyses suggest that trnaphe is the only trna encoded on the cloned 5 kb dna fragment. the trnaphe gene contains an intervening sequence 16 nucleotides in length located one nucleotide 3' to the anticodon position. the trnaphe coding region of neurospora and yeast are 91% conserved, whereas their intervening sequences are only 50% identical. the pattern of sequence conservation is consistent with a proposed seco ...19806449692
evolutionary origins of vertebrate hormones: substances similar to mammalian insulins are native to unicellular eukaryotes.tetrahymena pyriformis, neurospora crassa, and aspergillus fumigatus that had been grown in simple defined media were extracted with acid ethanol by a classic method for recovering insulin from pancreas. after filtration of the extracts on sephadex g-50, distinct peaks of insulin immunoreactivity were recovered in the region typical of insulin. the gel-filtered material from the tetrahymena had reactivity in the pork insulin radioimmunoassay about equal to its reactivity in the insulin bioassay ...19806449704
biogenesis of glyoxysomes. synthesis and intracellular transfer of isocitrate lyase.biosynthesis of isocitrate lyase, a tetrameric enzyme of the glyoxysomal matrix, was studied in neurospora crassa, in which the formation of glyoxysomes was induced by a substitution of sucrose medium by acetate medium. 1. translation of neurospora mrna in reticulocyte lysates yields a product which has the same apparent molecular weight as the subunit of the functional enzyme. using n-formyl[35s]methionyl-trnafmet as a label, the translation product shows the same apparent size which indicates ...19806450681
purification, properties and synthesis of delta-aminolaevulinate dehydratase from neurospora dehydratase, the second and rate-limiting enzyme of the haem-biosynthetic pathway, was purified 300-fold from induced cultures of neurospora crassa. the native enzyme has a mol.wt. of about 350000, whereas the salt-treated enzyme after incubation at 37 degrees c for 10 min has a mol.wt. of about 232000. the mol.wt. of the subunit is about 38000. antibodies to the purified enzyme were raised in rabbits. by using radiolabelling and immunoprecipitation techniques it was shown ...19806451221
kinetic properties of fatty acid synthetase of neurospora crassa.the kinetic properties of fatty acid synthetase, extracted from the mycelia of neurospora crassa, were studied to determine the role of the multi-enzyme complex in the regulation of long chain saturated fatty acid synthesis. acetyl-coa, a substrate, affects the fatty acid synthetase with increasing concentration in a normal michaelis-menton kinetic mode. malony-coa, another substrate, activates the synthetase in a homotropic manner up to 35 microm with a hill coefficient of 2.8. above that conce ...19806451784
effect of regulatory mutations of sulphur metabolism on the levels of cysteine- and homocysteine-synthesizing enzymes in neurospora crassa.1. regulation of four enzymes involved in cysteine and homocysteine synthesis, i.e. cysteine synthase (ec, homocysteine synthase (ec, cystathionine beta-synthase (ec 2.1.22) and gamma-cystathionase (ec was studied in the wild type and sulphur regulatory mutants of neurospora crassa. 2. homocysteine synthase and cystathionine beta-synthase were found to be regulatory enzymes but only the former is under control of the cys-3 - scon system regulating several enzymes of ...19806455895
construction and characterization of salmonella typhimurium strains that accumulate and excrete alpha- and beta-isopropylmalate.two salmonella typhimurium strains, which could be used as sources for the leucine biosynthetic intermediates alpha- and beta-isopropylmalate were constructed by a series of p22-mediated transductions. one strain, jk527 [flr-19 leua2010 delta(leud-ara)798 fol-162], accumulated and excreted alpha-isopropylmalate, whereas the second strain, jk553 (flr-19 leua2010 leub698), accumulated and excreted alpha- and beta-isopropylmalate. the yield of alpha-isopropylmalate isolated from the culture medium ...19806991477
physicochemical characterization of the ribosomal rna species of the mollusca. molecular weight, integrity and secondary-structure features of the rna of the large and small ribosomal subunits.1. the rrna species of the cephalopoda octopus vulgaris and loligo vulgaris were found to have unexpectedly high sedimentation coefficients and molecular weights. in 0.1 m-nacl the l-rrna (rna from large ribosomal subunit) has the same s20 value as the l-rrna of the mammals (30.7s), whereas the s-rrna (rna from small ribosomal subunit) sediments at a faster rate (20.1s) than the s-rrna of both the mammals and the fungi (neurospora crassa) (17.5s). the molecular weights of the l-rrna were determi ...19807458915
identification of the molybdenum cofactor in chlorate-resistant mutants of escherichia coli.experiments were performed to determine whether defects in molybdenum cofactor metabolism were responsible for the pleiotropic loss of the molybdoenzymes nitrate reductase and formate dehydrogenase in chl mutants of escherichia coli. in wild-type e. coli, molybdenum cofactor activity was present in both the soluble and membrane-associated fractions when the cells were grown either aerobically or anaerobically, with and without nitrate. molybdenum cofactor in the soluble fraction decreased when t ...19817026535
the influence of growth conditions on the synthesis of molybdenum cofactor in proteins mirabilis.cell-free extracts of proteus mirabilis were able to reconstitute nadph-dependent assimilatory nitrate reductase in crude extracts of the neurospora crassa mutant strain nit-1, lacking molybdenum cofactor. molybdenum cofactor was formed in the cytoplasm of the bacterium even in the presence of oxygen during growth though under these conditions no molybdo enzymes are formed. as a consequence no cofactor could be released by acid treatment from membranes of cells growth aerobically. the amount of ...19817030254
pyruvate dehydrogenase complex from baker's yeast. 1. purification and some kinetic and regulatory properties.pyruvate dehydrogenase complex, for the first time, was highly purified from commercial baker's yeast (saccharomyces cerevisiae). proteolytic degradation was prevented by the inclusion of the protease inhibitors pepstatin a, leupeptin, and phenylmethanesulfonyl fluoride during the enzyme purification. the yield from 1 kg of pressed yeast was about 15--20 mg enzyme with a specific activity of 17--30 u/mg. most of the kinetic and regulatory properties of the yeast enzyme were found similar to thos ...19817030740
biochemical analysis of mutants defective in nitrate assimilation in neurospora crassa: evidence for autogenous control by nitrate reductase.a biochemical analysis of mutants altered for nitrate assimilation in neurospora crassa is described. mutant alleles at each of the nine nit (nitrate-nonutilizing) loci were assayed for nitrite reductase activity, for three partial activities of nitrate reductase, and for nitrite reductase activity. in each case, the enzyme deficiency was consistent with data obtained from growth tests and complementation tests in previous studies. the mutant strains at these nit loci were also examined for alte ...19816460156
mutagenesis at the ad-3a and ad-3b loci in haploid uv-sensitive strains of neurospora crassa. v. comparison of dose--response curves of single- and double-mutant strains with wild-type.the interactions of mutant alleles that individually confer radiation sensitivity in neurospora crassa are being studied with regard to their effects on radiation-induced inactivation and forward-mutation induction at the ad-3 loci. this paper reports attempts to construct 3 double-mutant strains containing the following pair-wise combinations of repair-deficient mutants: upr-1,uvs-2; uvs-2,uvs-6; and uvs-3,uvs-6. the double-mutant strain with the 2 excision-repair-deficient mutants upr-1 and uv ...19816460180
solubility of (1 leads to 3)-beta-d/(1 leads to 6)-beta-d-glucan in fungal walls: importance of presumed linkage between glucan and saccharomyces cerevisiae, neurospora crassa, aspergillus nidulans and coprinus cinereus most of the alkali-insoluble (1 leads to 3)-beta-d/(1 leads to 6)-beta-d-glucan of the wall can be extracted with dimethyl sulphoxide. the same fraction, and in saccharomyces cerevisiae a small additional fraction, can be extracted by a destructive procedure involving 40% naoh at 100 degrees c. the small fraction of the glucan which resists this treatment becomes soluble after a subsequent treatment with h ...19816460846
estimation of deuteration levels in whole cells and cellular proteins by 1h n.m.r. spectroscopy and neutron scattering.methods using conventional fourier transform 1h n.m.r. spectroscopy at 250 mhz for the determination of the overall deuteration levels of cells cultured in media containing 2h2o or deuterated carbon sources are described. these were developed for escherichia coli as a model, and extended to neurospora crassa hyphae and mouse myeloma cells p815. the results were investigated by 1h n.m.r. and neutron scattering measurements on deuterated proteins that were obtained from e. coli. it is concluded th ...19816461329
studies on myo-inositol-1-phosphate from lilium longiflorum pollen, neurospora crassa and bovine testis. further evidence that a classical aldolase step is not utilized. 19816456770
neurospora crassa nad(p)h-nitrite reductase. studies on its composition and structure.neurospora crassa nitrite reductase (mr = 290,000) catalyzes the nad(p)h-dependent 6-electron reduction of nitrite to ammonia via flavin and siroheme prosthetic groups. homogeneous n. crassa nitrite reductase has been prepared employing conventional purification methods followed by affinity chromatography on blue dextran-sepharose 4b. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of homogeneous nitrite reductase reveals a single subunit band of mr = 140,000. isoelectric focusing of d ...19816457037
folylpoly-gamma-glutamate synthesis by bacteria and mammalian cells.the purification and properties of folylpolyglutamate synthetase from corynebacterium sp, and some properties of partially purified enzyme from lactobacillus casei, streptococcus faecalis, neurospora crassa, pig liver, and chinese hamster ovary cells, are described. the corynebacterium enzyme catalyzes a mgatp-dependent addition of glutamate to a variety of reduced pteroate and pteroylmono-, di-, and triglutamate substrates, with the concomitant production of mgadp and phosphate. although glutam ...19816458762
the cell-free protein synthesis system from the 'slime' mutant of neurospora crassa. preparation and characterisation of importance of 7-methylguanosine for translation of viral and cellular mrnas.a simple procedure for preparation of a cell-free protein synthesis system (23000 x g supernatant) from the protoplast-like 'slime' mutant of neurospora crassa is described. a variety of messenger rnas of viral and cellular origin could be efficiently and faithfully translated in this system into proteins with mr as large as 180000. the importance of the 7-methylguanosine cap for mrna translation in the neurospora system was studied in detail using the cap analogs and chemically decapped messeng ...19816459928
cellular and extracellular siderophores of aspergillus nidulans and penicillium chrysogenum.aspergillus nidulans and penicillium chrysogenum produce specific cellular siderophores in addition to the well-known siderophores of the culture medium. since this was found previously in neurospora crassa, it is probably generally true for filamentous ascomycetes. the cellular siderophore of a. nidulans is ferricrocin; that of p. chrysogenum is ferrichrome. a. nidulans also contains triacetylfusigen, a siderophore without apparent biological activity. conidia of both species lose siderophores ...19816242827
two classes of replicating molecules of adenovirus type 2 dna.replicating dna of human adenovirus type 2, identified as partly single-stranded viral dna in which [3h]thymidine is readily incorporated, was found to be separated into two fractions by chromatography on hydroxyapatite. whereas one of the these fractions was eluted with 180 mm phosphate, the other one was eluted at the same concentration, 240 mm, as fully double-stranded dna. the physical properties of the 180 and 240 mm fractions, in particular their buoyant densities in solutions of cscl and ...19817248295
genetic regulation of the qa gene cluster of neurospora crassa: induction of qa messenger ribonucleic acid and dependency on qa-1 in vitro protein-synthesizing system (rabbit reticulocyte) was programmed with total polyadenylated messenger ribonucleic acid from wild type and various mutants in the qa gene cluster of neurospora crassa. the products of two of the qa genes, quinate dehydrogenase (qa-3+) and dehydroshikimate dehydratase (qa-4+), were identified by specific immunoprecipitation and sodium dodecyl sulfate-slab gel electrophoresis. the results indicated that for both genes induction of a specific enzyme activit ...19819279395
mutagen sensitivities and mutator effects of mms-sensitive mutants in neurospora.7 mus (mutagen-sensitive) mutants of neurospora crassa, which are more sensitive to the toxic effects of mms (methyl methanesulfonate) than wild-type, were investigated for cross-sensitivities to other mutagens and inhibitors. these mutants have recently been mapped in 5 new genes, mus-7 to mus-11, and mutant alleles from each gene were checked for their effects on mutation frequencies. it was found that mutants in 3 of these 5 genes showed radiation-induced mutation frequencies similar to wild- ...19816451802
control of growth and of the nuclear division cycle in neurospora crassa. 19816452573
the nucleotide sequence at the 3'-end of neurospora crassa 25s-rrna and the location of a 5.8s-rrna binding site.the sequence of 110 nucleotides adjacent to the 3'-end of neurospora crassa 25s-rrna has been derived by chemical sequencing methods. sequences present between 40 and 85 nucleotides of the 3'-end were found to complement sequences at the 3'- and 5'-ends of 5.8s-rrna. interaction was shown to occur between 5.8s-rrna and a specific 3'-terminal fragment of 85 nucleotides derived from 25s-rrna. we have also demonstrated that the nucleotide sequence at the 3'-end of n. crassa 5.8s-rrna (-ucauuoh) is ...19816453330
nucleotide sequence of 5s ribosomal rna from aspergillus nidulans and neurospora crassa.the nucleotide sequences of 5s rrna molecules isolated from the cytosol and the mitochondria of the ascomycetes a. nidulans and n. crassa were determined by partial chemical cleavage of 3'-terminally labelled rna. the sequence identity of the cytosolic and mitochondrial rna preparations confirms the absence of mitochondrion-specific 5s rrna in these fungi. the sequences of the two organisms differ in 35 positions, and each sequence differs from yeast 5s rrna in 44 positions. both molecules conta ...19816453331
incorporation of photolabile azido fatty acid probes in neurospora crassa and saccharomyces cerevisiae. 19816453723
mitochondrial ribosome assembly in neurospora crassa. purification of the mitochondrially synthesized ribosomal protein, neurospora, one mitochondrial ribosomal protein (s-5, mr = 52,000) is synthesized intramitochondrially and is presumably encoded by mitochondrial dna. we have developed a rapid method for the purification of s-5 which takes advantage of its high affinity for carboxymethyl-sepharose in the presence of 6 m urea. using this method, s-5, at purity greater than 95%, can be prepared by column chromatography in a single batch elution step. the amino acid composition of s-5 was determined. judged by ...19816453873
mutagenesis at the ad-3a and ad-3b loci haploid uv-sensitive strains of neurospora crassa. iii. comparison of dose-response curves for inactivation and mutation induced by gamma-rays.gamma-ray-induced inactivation and induction of mutations at the ad-3a and ad-3b loci of neurospora crassa have been compared among 6 different uv-sensitive strains and a standard wild-type strain. the 6 strains show varying degrees of sensitivity to gamma-ray-induced inactivation, with the relative sensitivity at 37% survival being uvs-6 greater than upr-1 greater than uvs-2 greater than uvs-3 greater than wild-type greater than uvs-5 greater than uvs-4. studies on the induction of ad-3 mutants ...19816454839
mutagenicity of fractions of cigarette smoke condensate in neurospora crassa and salmonella typhimurium.the mutagenicities of selected fractions of cigarette smoke condensate (csc) were studied in neurospora crassa for the presence of direct-acting mutagens. cscs from the university of kentucky reference cigarette 1r1 were assayed in a forward-mutation test at the adenine-3 (ad-3) region in resting conidia of a 2-component heterokaryon. direct-acting mutagenic activity was found in an enriched polycyclic aromatic hydrocarbons (epah) fraction and in a basic fraction (swain 5). no direct-acting muta ...19816454842
mutagenicity of cigarette smoke condensate in neurospora crassa.the mutagenicity of cigarette smoke condensate (csc) was investigated in neurospora crassa in the presence and absence of s9 mix prepared from aroclor-1254-induced rat liver. csc from the university of kentucky reference cigarette 1r1 was assayed in a forward-mutation test at the adenine-3 (ad-3) region in resting conidia of 2-component heterokaryons. in the absence of s9 mix, csc exhibited direct-acting mutagenicity. csc was also mutagenic in the presence of s9 mix, but higher doses were requir ...19816454843
genetic screening of compounds used in drug abuse treatment. ii. methadone.several compounds used clinically in drug abuse therapy were evaluated for genetic activity in a series of in vivo and in vitro assays. the second report in this series describes the results for one of these compounds, methadone. a previous report described the results for naltrexone. methadone is a synthetic narcotic analgesic used as a substitute for heroin in drug detoxification programs. methadone demonstrated weak activity in the e. coli dna repair system and in the neurospora crassa and th ...19816455283
genetic screening of compounds used in drug abuse treatment. iii. laam.several compounds used clinically in drug abuse therapy were evaluated for genetic activity in a series of in vivo and in vitro assays. this third report in the series describes the results for one of these compounds, laam (l-alpha-acetyl methadol). previous reports described results from a three phase testing program for naltrexone and methadone. laam is related chemically to the narcotic analgesic oxymorphine, and is related chemically to a narcotic antagonist, naloxone. laam exhibited genetic ...19816455284
cloning the quinic acid (aq) gene cluster from neurospora crassa: identification of recombinant plasmids containing both qa-2+ and qa-3+.a 22.2-kb insert of neurospora crassa dna containing at least two of the genes from the inducible catabolic quinic acid pathway has been cloned into the cosmid vehicle phc79 resulting in a recombinant plasmid, pmsk308. the qa-2+ locus (which encodes catabolic dehydroquinase) is functionally expressed in both escherichia coli and qa-2 mutants of n. crassa transformed with pmsk308 plasmid dna. expression of the qa-3 gene (which encodes quinate dehydrogenase) is only detected upon reintroduction in ...19816266928
purification and identification of calmodulin from neurospora crassa. 19816273221
mutagenesis at the ad-3a and ad-3b loci in haploid uv-sensitive strains of neurospora crassa. iv. comparison of dose-response curves for mnng, 4nqo and icr-170 induced inactivation and mutation-induction.the genetic effects of mnng, 4nqo and icr-170 have been compared on 5 different uv-sensitive strains and a standard wild-type strain of neurospora crassa with regard to inactivation and the induction of forward-mutations at the ad-3a and ad-3b loci. whereas all uv-sensitive strains (upr-1, uvs-2, uvs-3, uvs-5 and uvs-6) are more sensitive to inactivation by mnng and icr-170 than wild-type, only uvs-5 shows survival comparable to wild-type after 4nqo treatment, all other strains are more sensitiv ...19816163076
different transport pathways of individual precursor proteins in mitochondria.transport of mitochondrial precursor proteins into mitochondria of neurospora crassa was studied in a cell-free reconstituted system. precursors were synthesized in a reticulocyte lysate programmed with neurospora mrna and transported into isolated mitochondria in the absence of protein synthesis. uptake of the following precursors was investigated: apocytochrome c, adp/atp carrier and subunit 9 of the oligomycin-sensitive atpase. addition of high concentrations of unlabelled chemically prepared ...19816167439
immunological approach to structural comparisons of assimilatory nitrate reductases.homogeneous squash cotyledon reduced nicotinamide-adenine dinucleotide (nadh):nitrate reductase (nr) was isolated using blue-sepharose and polyacrylamide gel electrophoresis. gel slices containing nr were pulverized and injected into a previously unimmunized rabbit. this process was repeated weekly and antiserum to nr was obtained after four weeks. analysis of the antiserum by ouchterlony double diffusion using a blue-sepharose preparation of nr resulted in a single precipitin band while immunoe ...198116662083
high frequency transfer of species specific mitochondrial dna sequences between members of the aspergillaceae.the mitochondrial genome of aspergillus nidulans var. echinulatus is approximately 20% larger than that of the closely related species aspergillus nidulans (eidam) winter. restriction enzyme mapping and electron microscopy has revealed that the size difference is due to the presence of six inserted sequences in the former. with the exception of a small number of species specific restriction sites and the six insertions/deletions, the two mitochondrial genomes appear identical. protoplast fusion ...198124190134
s1 nuclease does not cleave dna at single-base mis-matches.three assays have been designed to detect the cleavage of duplex phi x174 dna at single-base mis-matches. studies with s1 nuclease failed to detect cleavage at mis-matches. s1 nuclease digestion at 37 and 55 degrees c failed to produce a preferential degradation of a multiply mis-matched heteroduplex when compared to a mis-match-free homo-duplex as analyzed by sedimentation on sucrose gradients. other heteroduplex templates were not cleaved by s1 nuclease at a defined single-base mis-match when ...19816274410
aminotransferase study of neurospora crassa ser-3 versus wild type st4a. 19816459952
an isolated pseudogene related to the 5s rna genes in neurospora crassa. 19816458767
purification and characterization of the plasma membrane atpase of neurospora crassa.the plasma membrane of neurospora crassa contains a proton-translocating atpase, which functions to generate a large membrane potential and thereby to drive a variety of h+-dependent co-transport systems. we have purified this atpase by a three-step procedure in which 1) loosely bound membrane proteins are removed by treatment with 0.1% deoxycholate; 2) the atpase is solubilized with 0.6% deoxycholate in the presence of 45% glycerol; and 3) the solubilized enzyme is purified by centrifugation th ...19816457834
isolation and characterization of plasma membranes from wild type neurospora crassa.a method has been developed to isolate plasma membranes with high atpase activity from wild type neurospora. cells are treated with snail enzyme to weaken their cell walls, disrupted by gentle homogenization in a medium designed to keep mitochondria and other organelles intact, and fractionated by differential centrifugation. after removal of mitochondria, several higher speed particulate fractions (particularly one sedimenting at 40,000 x g) contain an atpase that can be identified as the plasm ...19816457833
temperature compensation of circadian period length in clock mutants of neurospora crassa.temperature compensation of circadian period length in 12 clock mutants of neurospora crassa has been examined at temperatures between 16 and 34 degrees c. in the wild-type strain, below 30 degrees c (the "breakpoint" temperature), the clock is well-compensated (q(10) = 1), while above 30 degrees c, the clock is less well-compensated (q(10) = 1.3). for mutants at the frq locus, mutations that shorten the circadian period length (frq-1, frq-2, frq-4, and frq-6) do not alter this temperature compe ...198116662086
larger precursors of mitochondrial translation products in neurospora crassa. indications for a precursor of subunit 1 of cytochrome c oxidase.specific labeling in vivo of the formylated n termini of mitochondrial translation products revealed that some mitochondrially synthesized proteins were not labeled this way. as a consequence, it was worthwhile considering that larger precursor proteins of mitochondrial translation products exist. although we used a rapid isolation procedure, only after 2-h of labeling in the presence of cycloheximide, could three additional mitochondrial translation products (molecular mass 45, 36, and 25 kilod ...19816276171
inhibition of rna synthesis in neurospora crassa hyphae treated with picolinic acid.picolinic acid, a metal-chelating agent, blocks the nuclei of germinating conidia of neurospora crassa in the g1 phase. the addition of picolinic acid to exponentially growing cultures of n. crassa in glucose medium causes an immediate inhibition of growth. concentrations higher than 50 mm completely inhibit growth of mycelia, whereas lower concentrations (20-30 mm) give only a partial inhibition. picolinic acid, added at the concentration of 20 mm, immediately blocks the accumulation of stable ...19816173217
some kinetic properties of the tryptophan-sensitive 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase from neurospora crassa.the steady-state kinetic properties of purified tryptophan-sensitive 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase from neurospora crassa were examined. the results suggest that the enzyme obeys a rapid-equilibrium ordered mechanism, in which phosphoenolpyruvate is the first substrate to bind and 3-deoxy-d-arabino-heptulosonate 7-phosphate is the second product to be released, rather than a ping pong mechanism as has been reported previously. the inhibition by tryptophan was found to be p ...19816122442
control of the flux in the arginine pathway of neurospora crassa. modulations of enzyme activity and concentration.the influence of particular enzyme activities on the flux of metabolites in a pathway can be estimated by 'modulating' enzymes (i.e. changing turnover or concentration) and measuring the response in various parts of the system. by controlling the nuclear ration of two genetically different nuclear types in heterokaryons, the enzyme concentrations at four different steps in the arginine pathway were decreased over a range. this range was extended by the use of bradytrophs, mutant strains specifyi ...19816462136
occurrence of xanthine dehydrogenase in chlamydomonas reinhardii: a common cofactor shared by xanthine dehydrogenase and nitrate reductase.wild-type chlamydomonas reinhardii cells have xanthine dehydrogenase activity when grown with nitrate, nitrite, urea, or amino acid media. mutant strains 102, 104, and 307 of chlamydomonas, lacking both xanthine dehydrogenase and nitrate reductase activities, were incapable of restoring the nadph-nitrate reductase activity of the mutant nit-1 of neurospora crassa, whereas wild type cells and mutants 203 and 305 had xanthine dehydrogenase and were able to reconstitute the nitrate reductase activi ...198124276829
characterization of a variant neurospora crassa mitochondrial dna which contains tandem reiterations of a 1.9 kb sequence.we have identified a second variant of neurospora mtdna which contains tandem, head-to-tail repeats of sequences at the boundary of eco ri-4 and 6. this region may contain a. major replication origin of neurospora mtdna.198124185958
cell-biology of ageing. 1. isolation of gamma-ray induced ageing mutants of neurospora crassa and their preliminary characterizations. 19816460560
highly conserved gc-rich palindromic dna sequences flank trna genes in neurospora crassa sequencing a 2200 bp region of the neurospora crassa mitochondrial dna encoding the 3' end of the large rrna gene and a cluster of six trna genes, we have found that the trna genes are flanked by highly conserved gc-rich palindromic dna sequences. an 18 bp long core sequence, 5'-cc ctgcag ta ctgcag gg-3', containing two closely spaced pst i sites, is common to all these palindromic sequences. each of the eight pst i sites mapped in the 2200 bp region consists of two closely spaced pst i sites ...19816276013
cytochrome c oxidase in cytochrome c oxidase-deficient mutant strains of neurospora crassa.three mutant strains of neurospora crassa, previously characterized as cytochrome c oxidase deficient, were found to possess this respiratory enzyme. the mitochondrial cytochrome contents of logarithmic phase cells of wild type (74a) and the respiration-deficient strains mi-3, cya-4-23, and cya-5-34 were investigated with low temperature difference spectrophotometry; two of the strains were found to possess cytochrome a. cytochrome c oxidase catalytic activity measurements performed on isolated ...19816270105
the involvement of proteolysis in conformational stability of the carbamoyl-phosphate synthetase/aspartate carbamoyltransferase enzyme of neurospora crassa.the pyrimidine-3 gene of neurospora crassa codes for a bifunctional enzyme catalysing the first two steps of the pyrimidine biosynthetic pathway. difficulties have been experienced in purification due to the lability of the enzyme. the enzyme loses carbamoyl-phosphate synthetase (carbon-dioxide: ammonia ligase (adp-forming, carbamate-phosphorylating), ec activity and undergoes a change in apparent molecular weight from the native 650,000 to 100,000 of the only detectable fragment. atte ...19816457644
purification & characterization of two forms of 5'amp nucleotidase form neurospora crassa. 19816273305
cold-sensitive mutation in neurospora crassa affecting the production of 17s ribosomal rna from ribosomal precursor rna.the cold-sensitive mutant strain of neurospora crassa, crib-1 (pj30201) has a conditional defect in ribosome biosynthesis. at 10 °c this mutant underproduces the small (37s) ribosomal subunit. experiments were done to study rrna synthesis in crib-1 after a shift from the permissive (25 °c) to the nonpermissive temperature and vice versa. the results showed that the primary cold-sensitive defect in crib-1 is in the function, rather than the synthesis, of a molecule needed for the production of th ...198124185860
photoregulation of the carotenoid biosynthetic pathway in albino and white collar mutants of neurospora crassa.the conversion of isopentenyl pyrophosphate to phytoene in neurospora crassa requires both a soluble and a particulate fraction. soluble and particulate enzyme fractions obtained from light-treated and dark-grown wild type, albino-1, albino-2, albino-3, and white collar-1 strains were mixed in various combinations, and the activity for conversion of [1-(14)c]isopentenyl pyrophosphate to phytoene was assayed. from such experiments it can be concluded that: (a) albino-3 is defective in the soluble ...198116661992
purification of vacuoles from neurospora crassa.the neurospora crassa vacuole, defined by its content of basic amino acids, polyphosphate, protease, phosphatases, and alpha-mannosidase, was purified to near homogeneity. the procedure depends upon homogenization of snail gut enzyme-digested cells in a buffer osmotically stabilized with 1 m sorbitol, differential centrifugation of the extract, and sucrose density gradient centrifugation of the organellar pellet. isopycnic centrifugation of vacuoles in 2.25 m sorbitol-metrizamide density gradien ...19819279392
genetic organization and transcriptional regulation in the qa gene cluster of neurospora crassa.a transcription map of the qa gene cluster of neurospora crassa has been constructed by using cloned dna fragments as hybridization probes. the mrnas encoded in the previously identified qa-2 (3-dehydroquinate hydro-lyase, ec, qa-4 (dehydroshikimate dehydratase), qa-3 (quinate:nad+ 3-oxidoreductase, ec, and qa-1 (regulatory protein) genes have been characterized. in addition, mrnas encoded in two new genes in this cluster (qa-x, qa-y) have been identified. regulation of this ...19816458044
photoreception in neurospora crassa: correlation of reduced light sensitivity with flavin deficiency.the effect of flavin deficiency on blue light responses in neurospora crassa was studied through the use of two riboflavin mutants (rib-1 and rib-2). the photoresponses assayed were the suppression of circadian conidiation, the phase shifting of the circadian conidiation rhythm, and the induction of carotenoid synthesis. flavin deficiency was induced in the rib-1 mutant by restrictive growth temperatures and in the rib-2 mutant by low levels of supplemental riboflavin. at 26 degrees c, a semires ...19816458042
characterization of 2-aminoisobutyric acid transport in neurospora crassa: a general amino acid permease-specific substrate.we report the characterization of an amino acid 2-aminoisobutyric acid was transported solely by the general amino acid permease and not by the neutral amino acid permease. furthermore, this substrate was not metabolized after transport. the potential for a system-specific nonmetabolizable substrate as a tool in the analysis of amino acid transport and its regulation is discussed.19816456264
mitochondrial biogenesis during fungal spore germination: respiration and cytochrome c oxidase in neurospora crassa.the germination of conidiospores of wild-type neurospora crassa was found to be dependent upon the function of the cytochrome-mediated electron transport pathway. the cyanide-insensitive alternate oxidase did not contribute significantly to the respiration of these germinating spores. the dormant spores contained all of the cytochrome components and a catalytically active cytochrome c oxidase required for the activity of the standard respiratory pathway, and these preserved components were respo ...19816268605
enzymatic synthesis and function of folylpolyglutamates.derivatives of folic acid occur in nature predominantly as poly (gamma-glutamyl) derivatives containing 2-8 glutamate residues. the data regarding the function of these derivatives, and their biosynthesis by eucaryotic and procaryotic folylpolyglutamate synthetases, is reviewed. the most universal functions of folylpolyglutamates appear to be (a) as the actual cofactors in vivo for folate dependent enzymes, (b) as inhibitors of folate dependent enzymes for which they are not substrates, and (c) ...19817027025
identification and characterization of recombinant plasmids carrying the complete qa gene cluster from neurospora crassa including the qa-1+ regulatory gene.the early reactions in the catabolism of quinic acid in neurospora crassa are controlled by at least four genes which are clustered on linkage group vii. three of the loci (qa-2, qa-4, and qa-3) encode enzymes that convert quinic acid to protocatechuic acid. the fourth gene (qa-1) encodes a positive regulatory protein which, in the presence of quinic acid, leads to the de novo synthesis of the other proteins in the qa cluster. this communication describes a series of recombinant plasmids that sp ...19816272290
the purification and molecular properties of the tryptophan-sensitive 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase from neurospora crassa.neurospora crassa contains three isoenzymes of 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, which are inhibited by tyrosine, tryptophan and phenylalanine respectively, and it was estimated that the relative proportions of the total activity were 54%, 14% and 32% respectively. the tryptophan-sensitive isoenzyme was purified to homogeneity as judged by polyacrylamide-gel electrophoresis and ultracentrifugation. the tyrosine-sensitive and phenylalanine-sensitive isoenzymes were only partia ...19816119978
mutational variants of the neurospora crassa nadp-specific glutamate dehydrogenase altered in a conformational equilibrium. 19816273586
a "stopper" mutant of neurospora crassa containing two populations of aberrant mitochondrial dna.[e35], an extranuclear mutant of neurospora crassa has all the phenotypic characteristics of the "stopper" mutants (de vries et al. 1980). in the present work, the mitochondrial dna as well as the mitochondrial translation products are characterized further. the primary mutational event appears to have been the deletion of about 4 kbp from the wild-type genome. moreover, after prolonged vegetative growth the mutant accumulates an 8-μm circular mtdna, which was demonstrated both by electronmicros ...198124190132
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