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isocitrate lyase from neurospora crassa: ph dependence of catalysis and interaction with substrates and inhibitors. 197718092
the mutagenicity of azathioprine in mice, drosophila melanogaster and neurospora crassa.the chemotherapeutic coumpound azathioprine was tested for possible mutagenicity in swiss albino mice, drosophila melanogaster and neurospora crassa. utilizing the dominant-lethal assay it was found that acute oral doses of azathioprine (2 times 25 mg/kg body weight), induced dominant-lethal mutations in mouse spermatocytes. chronic oral doses of azathioprine (2 times 25 mg/kg body weight/week for 10 weeks) resulted in a greater rate of dominant-lethality. this increase was not permanent, and by ...1975124817
characterization of 5.8s ribosomal ribonucleic acid in neurospora crassa.neurospora crassa ribosomes contain a species of ribonucleic acid (rna) of molecular weight 54,000, similar to 5.8s ribosomal rna previously described for other eukaryotic organisms. the 5.8s rna from n. crassa was found to be released by heat treatment at 60 c from 25s ribosomal rna but not from 18s ribosomal rna. the base composition of n. crassa 5.8s rna was similar to that of 5.8s rna from saccharomyces cerevisiae, but differed from animal 5.8s rna. during the course of this study, it was di ...1975126993
mutagenicity assays on fluorescent whitening agents using microorganisms.six fluorescent whitening agents (fwas) have been re-examined for their activity as inducers of cytoplasmic petite mutants and mitotic gene conversion in diploid yeast saccharomyces cerebisiae and reversion from auxotrophy to prototrophy in neurospora crassa, escherichia coli and salmonella typhimurium. the results provide no indication that the fwas examinded produce mutagenic changes or any other alterations in the gene material. in a recent re-examination with salmonella using the method of a ...1975132347
lysine catabolism in rhizoctonia leguminicola and related fungi.the catabolism of lysine was studied in several yeasts and fungi. results with cell-free extracts of rhizoctonia leguminicola support a proposed pathway involving (d- and l-) epsilon-n-acetyllysine, alpha-keto-epsilon-acetamidohexanoic acid, delta-acetamidovaleric acid, and delta-aminovaleric acid in the conversion of l-lysine to shortchain organic acids. label from radioactive l-lysine was found to accumulate in d- and l-epsilon-n-acetyllysine, delta-acetamidovaleric acid, delta-aminovaleric ac ...1976131119
gaps in dna synthesized by ultraviolet light-irradiated wi38 human cells.dna replication in ultraviolet-irradiated human cells was examined by treatment of the extracted dna with a single-strand specific endonuclease from neurospora crassa. wi38 cells were uniformly labeled with 32pi for two generations before irradiation and then labeled with [3h]thymidine after irradiation. the isolated dna was sedimented in neutral sucrose gradients after incubation with the endonuclease. the endonuclease treatment had no effect on the sedimentation profiles of either [32p]dna or ...1976130925
hyphal wall growth in neurospora crassa and geotrichum candidum.growth of the walls of hyphae of neurospora crassa and geotrichum candidum was studied using longitudinal and serial transverse sectioning methods. rigidification of the hyphal wall below the extension zone did not appear to involve the gross formation of a secondary wall since the transition from extensible to non-extensible wall was not associated with an increase in thickness. however, behind the extension zone the walls leading hyphae of n. crassa increased in thickness until eventually they ...1975128612
pyrolysis gas chromatography as an aid to the identification of penicillium species.using pyrolysis gas chromatography it was possible to identify each of a series of eleven penicillium species and the related species aspergillus niger cmi 31821 and neurospora crassa cmi 75723, based on relative peak heights and retention times of the most reproducible peaks in each pyrogram.1976128559
inactivation of carotenoid-producing and albino strains of neurospora crassa by visible light, blacklight, and ultraviolet radiation.suspensions of neurospora crassa conidia were inactivated by blacklight (bl) radiation (300 to 425 nm) in the absence of exogenous photosensitizing compounds. carotenoid-containing wild-type conidia were less sensitive to bl radiation than albino conidia, showing a dose enhancement factor (def) of 1.2 for dose levels resulting in less than 10% survival. the same strains were about equally sensitive to shortwave ultraviolet (uv) inactivation. the kinetics of bl inactivation are similar to those o ...1976128556
arrangement of sequences in the inverted terminal repetition of adenovirus 18 dna.in contrast to the single-stranded circular molecules produced with denatured dna from other adenoviruses, there was associated with nearly all circular molecules of adenovirus type 18 a visible, duplex projection. these projections had a mean contour length of 0.31 +/- 0.12 mum, equivalent to approximately 3% of genome length. individual projections ranged in size from 0.1 to 2 mum. alkaline sucrose gradient purification of single-stranded molecules did not affect formation of these projections ...1975127173
purification and properties of the fatty acids synthetase complex from neurospora crassa, and the nature of the fas-mutation.a procedure is described for the purification of the fatty acid synthetase complex (fas) from neurospora crassa. the enzyme complex has a molecular weight of 2.3 times 10(6), contains 6 mol of 4'-phosphopantetheine per mol, and on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate gives a single band, or a closely spaced doublet, which comigrates with standard myosin (molecular weight, 2 times 10(5)). since the slightly retarded component in the doublet accounts for all ...1975126228
regulation of exocellular proteases in neurospora crassa: metabolic requirements of the process.to induce exocellular proteolytic enzyme from carbon-starved exponential-phase cells of neurospora crassa, both a protein substrate and an activating protease of certain specific properties must be present at the same time. the cells must be capable of protein synthesis, since cycloheximide inhibits the process, but cell growth, as determined by increase in cell mass, does not appear to be required. both soluble (bovine serum albumin, myoglobin) and insoluble protein substrates (collagen, corn z ...1975125263
control of the synthesis of a single enzyme by multiple regulatory circuits in neurospora crassa.neurospora crassa synthesizes and secretes an extracellular protease into its growth medium when an exogenous protein serves as its principal source of sulfur, nitrogen, or carbon. the enzymes produced under these three growth conditions have been compared by a number of criteria. the results indicate that the same extracellular protease with a molecular weight of 31,000 is synthesized during the three different metabolic conditions. a regulatory mutant, which lacks a positive signal required fo ...1975124058
in vitro restoration of nitrate reductase: investigation of aspergillus nidulans and neurospora crassa nitrate reductase mutants.extracts of aspergillus nidulans wild type (bi-1) and the nitrate reductase mutant niad-17 were active in the in vitro restoration of nadph-dependent nitrate reductase when mixed with extracts of neurospora crassa, nit-1. among the a. nidulans cnx nitrate reductase mutants tested, only the molybdenum repair mutant, cnxe-14 grown in the presence of 10-minus 3 m na2 moo4 was active in the restoration assay. aspergillus extracts contained an inhibitor(s) which was measured by the decrease in nadph- ...1975123779
nitrogen-metabolizing enzymes of diplodia maydis, a zea mays l. stalk rot causing fungus.the nitrogen source available to diplodia maydis in vivo is reported to affect the severity of stalk rot in maize. nitrate and (or) ammonium salts were tested for their effect on the type of nitrogen metabolism found in diplodia maydis in vitro. the level of glutamate dehydrogenase remained essentially constant on either nitrogen salt but nitrate reductase was induced by growth on nitrate salts and was not extractable on ammonium salts. properties of nitrate reductase reported here are similar t ...197935273
nitrogen source regulates glutamine synthetase mrna levels in neurospora crassa.neurospora crassa glutamine synthetase mrna was measured by its capacity to direct the synthesis of the specific protein in a cell-free system derived from rabbit reticulocytes. n. crassa cultures grown on glutamate as the sole nitrogen source had higher mrna activities than did those grown on glutamine. the differences were about 10-fold when polysomal rna was used for translation and about 5-fold when either total cellular rna or polyadenylic acid-enriched cellular rna was used. these data ind ...197831352
isolation of a multiprotein complex containing cytochrome b and c1 from neurospora crassa mitochondria by affinity chromatography on immobilized cytochrome c. difference in the binding between ferricytochrome c and ferrocytochrome c to the multiprotein complex.a multiprotein complex which contains in equimolar amounts two cytochromes b (mr each about 27,000), one cytochrome c1 (mr 31,000) and six subunits without known prosthetic groups (mr 8000, 12,000, 14,000, 45,000, 45,000, and 50,000) has been isolated from the mitochondrial membranes of neurospora crassa by affinity chromatography on immobilized cytochrome c. the chromatographic separation was based upon the specific binding of the complex to ferricytochrome c coupled to sepharose and its specif ...197827360
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. iv. the cooh-terminal 669 residues of the peptide chain; comparison with other glutamate dehydrogenases.a sequence is presented for the cooh-terminal 669 residues of the nad-specific glutamate dehydrogenase of neurospora crassa. comparison of this sequence with those of the vertebrate glutamate dehydrogenases of chicken and bovine liver and with the nadp-specific enzyme of neurospora shows some similarities in sequences around residues previously identified as important for the function of these enzymes. these are: (a) the reactive lysine residue of low pk in the nadp and the vertebrate enzymes; ( ...197721191
the stereospecificity of nitrate reductase for hydrogen removal from reduced pyridine nucleotides.the stereospecificity of the hydrogen removal from reduced pyridine nucleotides catalyzed by nitrate reductase (nadh : nitrate oxidoreductase, ec 1.6.6.1, and nad(p)h : nitrate oxidoreductase, ec 1.6.6.2) was investigated. a high degree of enzyme purification was required to obtain conclusive results. improvements are described for the purification of nitrate reductase from chlorella fusca and from spinach (spinacea oleracea, l.) leaves. the latter enzyme is shown to contain a cytochrome. with h ...197716653
lytic enzymes in the autolysis of filamentous fungi.the degrees of autolysis attained by five different genera of filamentous fungi during an incubation period of 60 days, under the same culture conditions were: 87.3% for penicillium oxalicum; 65.9% for neurospora crassa; 62.7% for polystictus versicolor; 51.7% for aspergillus niger and 23.5% for nectria galligena. n. crassa, a. niger and p. versicolor reached the end of the autolysis during this incubation period (60 days), whereas p. oxalicum and n. galligena did not. the excretion of the lytic ...197613304
identification of a functional arginine residue involved in coenzyme binding by the nadp-specific glutamate dehydrogenase of neurospora.the nadp-specific glutamate dehydrogenase (ec 1.4.1.4) of neurospora crassa is inhibited by reaction with 1,2-cyclohexanedione which binds to arginine residues. with the 14c-labeled reagent, a peptide was isolated with the sequence: gly-gly-leu-arg-leu-his-pro-ser-val-asn-leu, corresponding to residues 78 through 88 in the protein. the arginine, residue 81, was present as n7,n8-(1,2-dihydroxycyclohex-1,2-ylene)-arginyl (or dhch-arginine). present evidence indicates that this arginine residue res ...19769404
histones of neurospora crassa.neurospora crassa chromatin isolated by a rapid method minimizing proteolytic degradation contains approximately one weight of acid-extractable basic protein per weight of dna. this basic protein consists of five major polypeptide species which are similar in size to the histone proteins of higher eukaryotes and are present in approximately the same molar ratios. these five polypeptides have been purified by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. their elec ...1976132444
molybdenum cofactors from molybdoenzymes and in vitro reconstitution of nitrogenase and nitrate reductase.a molybdenum cofactor (mo-co) from xanthine oxidase (xanthine:oxygen oxidoreductase, ec 1.2.3.2) can be isolated from the enzyme by a technique that has been used to isolate an iron-molybdenum cofactor (femo-co) from component i of nitrogenase. n-methylformamide is used for the extraction of these molybdenum cofactors. mo-co from xanthine oxidase activates nitrate reductase (nadph:nitrate oxidoreductase, ec 1.6.6.2) in an extract from neurospora crassa mutant strain nit-1; however, femo-co is un ...1977146198
the cleavage of transfer rna by a single strang specific endonuclease from neurospora crassa.endonuclease from neurospora crassa (ncnase), an enzyme with specificity for polynucleotides lacking an ordered structure, was shown to cleave su+3 trnatyr from e. coli preferentially in the anticodon region. the enzyme cleaved unfractionated trna primarily to 30 - 50 nucleotide size fragments, implying that most or all trna species are also cleaved in the anticodon region. the 3' terminal sequence c-a was cleaved as well. the results are discussed with respect to the three dimensional structure ...1975125412
genetic characterization of adenine-3 mutants induced by 4-nitroquinoline 1-oxide and 4-hydroxyaminoquinoline 1-oxide in neurospora crassa.specific locus mutations induced by the chemical carcinogens, 4-nitroquinoline 1-oxide (4nqo) and 4-hydroxyaminoquinoline 1-oxide (4haqo), have been characterized to obtain a presumptive identification of the genetic alterations at the molecular level. one hundred eighty-four 4nqo-induced and 219 4haqo-induced ad-3 mutants of neurospora crassa obtained in previous studies were studied with a series of genetic tests that permits determination of their genotype and the frequencies of point mutatio ...1975122814
neurospora crassa mitochondrial transfer rnas.total mitochondrial trna from neurospora crassa was characterized by base composition analysis, one- and two-dimensional gel electrophoreses and reversed-phase chromatography on rpc5. the guanosine + cytidine content was about 43%, as compared to 60% for cytoplasmic trna. the modified nucleoside content was low and about the same as that of total yeast mitochondrial trna, though the g + c content is very different. we found psi, t, hu, t6a, m1g, m2g, m22g. neither the eukaryotic "y" base, nor th ...1978152130
mutagenicity of actinomycin d in neurospora crassa.actinomycin d is known to bind to native dna and is widely used as an antineoplastic agent and inhibitor of dna-dependent rna and protein synthesis. we report here the induction by actinomycin d of purple adenine-requiring mutants (ad-3) in wild-type neurospora crassa. a significant increase in the frequency of ad-3 mutants was evident when the organism was grown vegetatively in the presence of actinomycin d; the mutation frequency was at least 3.6 per 106 survivors. the actinomycin d-induced ad ...197555964
immunoelectrophoretic determination of nitrate reductase in neurospora crassa. 197940454
metabolism of mandelic acid by neurospora crassa.preliminary studies on the metabolism of manelic acid by neurospora crassa reveal the operation of a pathway for its degradation which involves benzoyl formic acid, benzaldehyde, benzoic acid, 4-hydroxybenzoic acid, and protocatechuic acid as the intermediates. this pathway is different from the followed by bacterial systems and is the same as that observed in aspergillus niger.197721739
the amino acid sequence of neurospora nadp-specific glutamate dehydrogenase. peptides from digestion with a staphylococcal proteinase.the extracellular proteinase of staphylococcus aureus strain v8 was used to digest the nadp-specific glutamate dehydrogenase of neurospora crassa. of 35 non-overlapping peptides expected from the glutamate content of the polypeptide chain, 29 were isolated and substantially sequenced. the sequences obtained were valuable in providing overlaps for the alignment of about two-thirds of the sequences found in tryptic peptides wootton, j. c., taylor, j, g., jackson, a. a., chambers, g. k. & fincham, ...19751001
use of the spot, plate and suspension test systems for the detection of the mutagenicity of environmental agents and chemical carcinogens in neurospora crassa.n23 and n24, selected from hundreds of ad-3 mutants, have been used as testers for the spot, plate and suspension tests in neurospora crassa. these two testers are highly sensitive to mutagens and are revertible by a specific group of chemicals. n23 can be reverted from an adenine-dependence to adenine-independence by agents which cause base-pair substitutions whereas n24 can be reverted by frameshift mutagens. studies described here show that spot, plate and suspension tests using testers n23 a ...1978149924
inhibition of neurospora crassa and yeast mitochondrial protein synthesis by ricin, a toxic protein inactive on e. coli protein synthesis. 1976133821
action of intracellular proteinases on mitochondrial translation products of neurospora crassa schizosaccharomyces pombe.gel electrophoretic analysis of mitochondrial membranes from neurospora crassa shows the presence of a polypeptide fraction with apparent molecular weights of 7000 - 1200, which is synthesized on mitochondrial ribosomes. this fraction comprises between 10 and 50% of total mitochondrial translation products. evidence is presented that the major part of this fraction is derived from components with higher apparent molecular weights by proteolytic activity. the proteolytic activity is located in ve ...1976133982
wall structure of the neurospora hyphal apex: immunofluorescent localization of wall surface antigens.antisera have been raised in rabbits against three wall fractions from neurospora crassa. fractions were separated according to mahadevan & tatum (1965), i.e. fraction i, glucan-peptide-galactosamine complex; fraction iii, laminarin-like glucan; and fraction iv, chitin. distinct patterns of immunofluorescent staining were obtained using an indirect staining method. hyphae stained with antiserum to fraction i showed maximum fluorescence in the apical and/or subapical regions: in both cases, fluor ...1976134131
physical map of neurospora crassa mitochondrial dna and its transcription unit for ribosomal rna.a circular denaturation and restriction map of mitochondrial dna from neurospora crassa is presented. the map shows the position of all twelve fragments produced by restriction endonuclease eco r i and the position of the largest hin iii fragment along the previously established map of at-rich sequences. the two wild type strains em 5256 and 7a differ in the lengths of two eco r i fragments. no difference was found between the mitochondrial mutant "poky" and its parent strain. the position of th ...1976137390
mutation induction by the antischistosomal drug f30066 in various test systems.the genetic activity of furapromidium (f30066), an antischistosomal drug, was studied in salmonella typhimurium, saccharomyces cerevisiae, neurospora crassa and cultured chinese hamster cells. the results show that f30066 induces gene mutations in s. typhimurium, n. crassa and chinese hamster cells. this compound also causes gene conversions in s. cerevisiae.1977138086
a complete cleavage map of neurospora crassa mtdna obtained with endonucleases eco ri and bam hi.a physical map of neurospora crassa mitochondrial dna has been constructed using specific fragments obtained with restriction endonucleases. the dna has 5 cleavage sites for endonuclease bam hi, 12 for endonuclease eco ri and more than 30 for endonuclease hind iii. the sequence of the eco ri and bam hi fragments has been established by analysis of partial fragments. by digestion of the eco ri fragments with bam hi, a complete overlapping map has been constructed. the position of the largest hind ...1977139928
neurospora crassa glutamine synthetase. translation of specific messenger ribonucleic acid in a cell-free system derived from rabbit reticulocytes.the total reticulocyte lysate cell-free protein-synthesizing system was incubated in the presence of neurospora crassa rna. with the aid of an antibody directed against purified n. crassa glutamine synthetase, the synthesis of a specific protein was detected. this protein precipitates with antiglutamine synthetase using both direct and indirect procedures, migrates with the same molecular weight as the monomer of n. crassa glutamine synthetase when subjected to acrylamide gel electrophoresis in ...197716013
mutation induction by rodent liver microsomal metabolities of aflatoxins b1 and g1 in neurospora crassa.the mutagenic activities of aflatoxins b1 and g1 were studied in the ad-3 test system of neurospora crassa by treatment of conidia with aflatoxin and liver homogenate for 2 h. no significant increase in the ad-3 mutation frequency over the spontaneous frequency was observed when either aflatoxin or mammalian liver homogenate was omitted from the test system. the ad-3 mutation frequencies increased to between 29 and 87/10(6) survivors, which is a 73- to 217-fold increase over the average spontane ...1976135208
regulation of exocellular protease in neurospora crassa: induction and repression under conditions of nitrogen starvation. 1977143241
the ribosomal rna genes on neurospora crassa mitochondrial dna are adjacent.hybridization of separated 24 s and 17 s ribosomal rna from neurospora crassa mitochondrial ribosomes to restriction fragments of mitochondrial dna leads to the conclusion that the large and small ribosomal rna are adjacent on the restriction endonuclease cleavage map of the dna. the distance between the two genes is estimated at 900 basepairs. this result is consistent with the existence of a ribosomal precursor rna in n. crassa mitochondria and is in contrast to the situation in yeast, where t ...1977143295
nucleotide sequence of neurospora crassa cytoplasmic initiator trna.initiator methionine trna from the cytoplasm of neurospora crassa has been purified and sequenced. the sequence is: pagcugcaum1ggcgcagcggaagcgcm22gcy*gggcucaut6aacccggagm7gu (or d) - cacucgaucgm1aaacgag*uugcagcuaccaoh. similar to initiator trnas from the cytoplasm of other eukaryotes, this trna also contains the sequence -aucg- instead of the usual -tphicg (or a)- found in loop iv of other trnas. the sequence of the n. crassa cytoplasmic initiator trna is quite different from that of the corresp ...1977146192
differences and similarities in chromatin structure of neurospora crassa and higher eucaryotes.the subunit structure of neurospora chromatin which contains a full histone complement (goff, 1976) exhibits both differences and similarities to chromatin of higher eucaryotes. the size of the dna per subunit is only 170 +/- 5 base pairs, as compared to 200 base pairs in higher eucaryotes. however, the internal structures of the subunits are closely related. they contain 140 base pairs of dna that are more tightly associated with the histone core and similarly arranged on the outside of the sub ...1976133762
isolation of neurospora crassa-bovine l-glutamate dehydrogenase hybrids [proceedings]. 1978154423
organization of the ribosomal ribonucleic acid gene cluster of neurospora crassa by means of restriction endonucleases and cloning in bacteriophage lambda [proceedings]. 1978154424
transcription and translation in e. coli of hybrid plasmids containing the catabolic dehydroquinase gene from neurospora crassa.two hybrid plasmids which carry the gene for neurospora crassa catabolic dehydroquinase (c-dhqase) and complement an arod6 (dehydroquinase-deficient) auxotroph of escherichia coli have been analyzed. one of these contains a 2.9 kilobase (kb) fragment cloned in the hindiii site of plasmid pbr322 (pvk57) and the other contains a 6.8 kb fragment cloned in the psti site (pvk88). restriction enzyme mapping of these plasmids has demonstrated that the 2.9 kb fragment is totally contained within the 6.8 ...1978154430
mutagenicity and mutagenic specificity of metronidazole and niridazole in neurospora crassa.mutagenicity and mutagenic specificity of niridazole and metronidazole, two chemotherapeutic agents used in the treatment of human parasitic diseases, were studied with the ad-3 test system of neurospora crassa. the results show that neither compound is mutagenic in resting conidia. in growing vegetative cells, however, both compounds are mutagenic in n. crassa. genetic analysis of the mutants indicated that niridazole induces predominantly base-pair substitution mutations. none of the niridazol ...1978153406
the dicyclohexylcarbodiimide-binding protein of the mitochondrial atpase complex from neurospora crassa and saccharomyces cerevisiae. identification and isolation.incubation of mitochondria from neurospora crassa and saccharomyces cerevisiae with the radioactive atpase inhibitor [14c]dicyclohexylcarbodiimide results in the irreversible and rather specific labelling of a low-molecular-weight polypeptide. this dicyclohexylcarbodiimide-binding protein is identical with the smallest subunit (mr 8000) of the mitochondrial atpase complex, and it occurs as oligomer, probably as hexamer, in the enzyme protein. the dicyclohexylcarbodiimide-binding protein is extra ...1979154405
enzymatic release of iron from sideramines in fungi. nadh:sideramine oxidoreductase in neurospora crassa.young mycelia of the fungus neurospora crassa contain a soluble nadh-linked sideramine reductase, which may be responsible for liberating iron in vivo from accumulated sideramines during iron-deficient cultivation. the enzymes can be assayed using a soluble supernatant fraction, edta, and an atmosphere of pure nitrogen. the enzyme is stable without loss of activity up to 45 degrees c and has an optimum of activity at ph 7.0. besides coprogen (km = 100 micrometer, v=2.8 nmol/min per mg protein), ...1977144535
expression in escherichia coli k-12 of the structural gene for catabolic dehydroquinase of neurospora crassa.the inducible quinic acid catabolic pathway of neurospora crassa is controlled by four genes, the qa cluster which includes structural genes qa-2, qa-3, qa-4 for three enzymes and a regulatory gene, qa-1. in this paper we report the molecular cloning of at least the qa-2 gene which encodes the catabolic dehydroquinase (5-dehydroquinate hydro-lyase, ec 4.2.1.10). endo.r.hindiii restriction endonuclease fragments of n. crassa dna from a qa-1(c) (constitutive) mutant and of escherichia coli plasmid ...1977143663
presence of an actin-like protein in mycelium of neurospora crassa.addition of atp, cacl2, and kcl to supernatants prepared from mycelia of snowflake (strain 507), a morphological mutant of neurospora crassa, results in the formation of filaments 70 nm in diameter. the "decorated" appearance of these filaments after incubation with heavy meromyosin from rabbits suggests they are actin-like.1978150412
comparison of the genetic activity of 5-nitroimidazole derivatives in escherichia coli, neurospora crassa, saccharomyces cerevisiae and drosophila melanogaster.5-nitroimidazoles, including metronidazole (compound 1) and 3 analogues (compounds 2, 3 and 4) of actual or potential chemotherapeutic use were assayed for genetic activity in test systems detecting forward and back mutations in escherichia coli k-12/343/113, forward mutations in neurospora crassa heterokaryon 12, mitotic gene conversion in the heteroallelic diploid yeast strain saccharomyces cerevisiae d4 and sex-linked recessive lethals in drosophila melanogaster. whereas metronidazole exhibit ...1979154545
interesting and unusual features in the sequence of neurospora crassa mitochondrial tyrosine transfer rna.the mitochondrial tyrosine trna from neurospora crassa has been sequenced and found to have several interesting features: (i) it resembles prokaryotic rather than eukaryotic tyrosine trnas in that it possesses a large variable loop (loop iii); moreover, it can be quantitatively aminoacylated by escherichia coli tyrosyl-trna synthetase but not by yeast tyrosyl-trna synthetase. (ii) this trna differs from all trna's sequenced to date in lacking the a residue at position 14 and the constant purine ...1979154673
literature survey of bacterial, fungal, and drosophila assay systems used in the evaluation of selected chemical compounds for mutagenic activity.literature reports were surveyed, with results noted from experiments in seven nonmammalian assay systems used for the detection of mutagenicity or other related genetic effects. a comparison was made of the activities of 54 selected noncarcinogens, procarcinogens, and ultimate carcinogens as revealed by these test systems. of the compounds tested, 49 (91%) were active in one or more of the assays, and 42 (78%) were positive in at least one system without having to be metabolically activated. in ...1979155170
arrangement of the genes coding for ribosomal ribonucleic acids in neurospora crassa.we have cloned and characterized neurospora crassa ribosomal deoxyribonucleic acid (rdna). the rdna is found as a tandemly repeated 6.0-megadalton sequence. we have mapped a portion of the rdna repeat unit with respect to its sites for 13 restriction endonucleases and defined those regions coding for the 5. 8s, 17s, and 26s ribosomal ribonucleic acids (rrna's). we have also isolated several clones containing 5s rrna sequences. the 5s rrna coding sequences are not found within the rdna repeat uni ...1979155688
inactivation of neurospora crassa conidia by singlet molecular oxygen generated by a photosensitized reaction.photodynamic damage of neurospora crassa conidia was studied in the presence of the photosensitizing dye, toluidine blue o. conidia which germinated to form colonies decreased in number as irradiation time became longer. the photoinactivation of conidia was suppressed by azide, bovine serum albumin, and histidine, and was stimulated in deuterium oxide. wild-type conidia were less sensitive to the irradiation than albino conidia. in the wild-type, carotenoid-enriched conidia were more resistant a ...1979155692
mutagenicity and mutagenic specificity of metronidazole and niridazole in neurospora crassa.mutagenicity and mutagenic specificity of niridazole and metronidazole, two chemotherapeutic agents used in the treatment of human parasitic diseases, were studied with the ad-3 test system of neurospora crassa. the results show that neither compound is mutagenic in resting conidia. in growing vegetative cells, however, both compounds are mutagenic in neurospora crassa. genetic analysis of the mutants indicate that niridazole induces predominantly base-pair substitution mutations. none of the ni ...1979156240
constitutive expression in escherichia coli of the neurospora crassa structural gene encoding the inducible enzyme catabolic dehydroquinase.in neurospora crassa the qa-2 gene, which encodes catabolic dehydroquinase, is under positive control exerted by the inducer quinic acid and an activator protein encoded in the closely linked qa-1 gene. in order to determine if this regulatory mechanism is maintained when the qa-2 gene is cloned on a recombinant plasmid and expressed in escherichia coli, molecular cloning experiments have been performed using dna isolated from a qa-1+ (inducible), a qa-1c (constitutive) and two qa-1 (non-inducib ...1979156301
ageing of neurospora crassa. viii. lethality and mutagenicity of ferrous ions, ascorbic acid, and malondialdehyde.ferrous ions were highly lethal and mutagenic to germinated conidia of neurospora crassa. at comparable survival, treatment with 0.2 mm ferrous ions was 14- and 50-fold more mutagenic than ultra-violet irradiation or x-rays, respectively, in the reversion of an inositol auxotroph. ascorbic acid alone (2 mm) was not reproducibly lethal and inhibited both the lethality and mutagenicity of ferrous ions. bovine superoxide dismutase (sod) completely inhibited the residual lethality of ferrous ascorba ...1979156825
nucleotide sequence and conserved features of the 5.8 s rrna coding region of neurospora crassa.the nucleotide sequence of neurospora crassa 5.8 s rdna and adjacent regions has been determined. the deduced 5.8 s rrna sequence of neurospora differs from the 5.8 s rrna sequence of saccharomyces cerevisiae at 13 of 158 residues. nine of these differences are clustered in a segment capable of forming a short hairpin secondary structure thought to be involved in the 28 s - 5.8 s rrna complex. these differences occur in pairs such that the potential secondary structure is preserved.1979156910
biosynthesis of carnitine in neurospora crassa.in growing cultures of neurospora crassa lysine auxotroph 33933, (a) beta-hydroxy-epsilon-n-trimethyllysine and gamma-n-trimethylaminobutyraldehyde, postulated precursors of carnitine in the rat, effectively blocked synthesis of labeles carnitine from epsilon-n-[ch3-3h]trimethyllysine; and (b) beta-hydroxy-epsilon-n[ch3-3h[trimethyllysine and gamma-n-[ch3-3h]trimethylaminobutyraldehyde were effectively utilized for carnitine formation. from these isotopic experiments, the latter steps of carniti ...1977144128
mediated mutagenesis of dimethylnitrosamine in neurospora crassa by various metabolic activation systems.four metabolic activation systems (growth mediated mycelium extract mediated, host mediated, and organ homogenate mediated) were used to study the mutagenic activity of dimethylnitrosamine (dmn) in both forward and reverse mutation systems in the ad-3 (adenine-3) region of neurospora crassa. dmn was not mutagenic in neurospora if conidia alone were treated. it was highly mutagenic, however, if conidia were treated with this compound under any of the four activation systems. quantitative differen ...1979154971
expression of the structural gene for catabolic dehydroquinase of neurospora crassa in escherichia coli k12. 1977157795
the mitochondrial ribosomes of neurospora crassa. ii. comparison of the proteins from neurospora crassa mitochondrial ribosomes with ribosomal proteins from neurospora cytoplasm, from rat liver mitochondria and from bacteria.1. it has been shown by datema et al. (datema, r., agsteribbe, e. and kroon, a.m. (1974) biochim. biophys. acta 335, 386--395) that neurospora mitochondria isolated in a mg2+-containing medium (or after homogenization of the mycelium in this medium and subsequent washing of the mitochondria in edta-containing medium) possess 80-s ribosomes; mitochondria homogenized and isolated in edta medium yield 73-s ribosomes. the ribosomal proteins of the subunits of 80-s and 73-s ribosomes were compared by ...1976133723
metallothionein: an exceptional metal thiolate protein.metallothioneins are unusual, low molecular weight proteins of extremely high sulphur and metabl content. they occur in substantial quantity and in multiple variant forms in parenchymatous tissues (liver, kidney, intestines) of vertebrates and certain microorganisms (neurospora crassa, yeast). they are though to play a central role in the cellular metabolism of metals such as zinc, copper and cadmium. all mammalian forms studied are single chains with 20 cysteinyl residues among a total of 61 am ...1979162047
genetic effects of pr toxin in eukaryotic microorganisms.the genetic activity of pr toxin, a mycotoxin from penicillium roqueforti, was studied in saccharomyces cerevisiae and neurospora crassa. the results show that pr toxin, without enzymic activation, causes gene conversion in s. cerevisiae strains d4 and d7, reverse mutation in s. cerevisiae strain d7 and n. crassa strain n24, and mitotic crossing-over in s. cerevisiae strain d7, in the log phase cells of s. cerevisiae the effects are more pronounced at alkaline than at acid ph. the active site re ...1979162284
the regulated catabolism of endogenous and exogenous phosphatidylinositol by saccharomyces cerevisiae leading to extracellular glycerophosphorylinositol and inositol.it was previously shown that phosphatidylinositol catabolism leads to the accumulation of glycerophosphorylinositol in the culture medium of saccharomyces cerevisiae. we now find that lack of an energy source (glucose) reduces the formation of glycerophosphorylinositol and increases extra-cellular inositol. this situation is reversed by refeeding glucose. [3h]phosphatidylinositol is the precursor of extra-cellular [3h]inositol with energy-starved cells. extracellular glycerophosphorylcholine and ...1975166987
partial amino-acid sequence of nad-specific glutamate dehydrogenase of neurospora crassa.parts of the primary structure of the nad-specific glutamate dehydrogenase [l-glutamate:nad oxidoreductase (deaminating), ec 1.4.1.2] from neurospora crassa are presented. segments of the sequence representing 886 unique amino-acid residues have been determined; the largest contains 267 residues. there are only short regions of possible homology between this enzyme and the glutamate dehydrogenases of bovine liver or the nadp-specific enzyme of neurospora. the large size of the subunit (116,000 m ...1975174080
inducible and constitutive kynureninases. control of the inducible enzyme activity by transamination and inhibition of the constitutive enzyme by 3-hydroxyanthranilate.the inducible kynureninase from neurospora crassa is inactivated by incubation with l-alanine or l-ornithine. the inactivated enzyme is resolved to the apoenzyme by dialysis. reactivation of the apoenzyme is achieved by incubation with pyridoxamine 5'-phosphate plus pyruvate, as well as with pyridoxal 5'-phosphate. the kynurenine hydrolysis proceeds linearly in the presence of added pyridoxal 5'-phosphate, or pyridoxamine 5'-phosphate plus pyruvate. these findings indicate that the fungal induci ...1979158014
differential rates of synthesis of glycerokinase and glycerophosphate dehydrogenase in neurospora crassa during induction. 1975165778
characterization of a seventh different subunit of beef heart cytochrome c oxidase. similarities between the beef heart enzyme and that from other species.beef heart cytochrome c oxidase has been resolved into seven subunits by electrophoresis in highly cross-linked gels containing urea and sodium dodecyl sulfate. the molecular weights of the polypeptides are estimated to be i, 35 400; ii, 24 100; iii, 21 000; iv, 16 800; v, 12 400; vi, 8200; and vii, 4400. it has been shown that subunits ii and iii can coelectrophorese on standard sodium dodecyl sulfate-polyacrylamide gels and appear as a single component with an apparent molecular weight of 22 5 ...1976181053
increased expression of a eukaryotic gene in escherichia coli through stabilization of its messenger rna.the expression of a cloned eukaryotic gene [catabolic dehydroquinase (3-dehydroquinate hydro-lyase, ec 4.2.1.10) (qa-2+) from neurospora crassa] is dramatically increased (as much as 100-fold) in escherichia coli strains deficient in polynucleotide phosphorylase (pnp) (polynucleotide: orthophosphate nucleotidyltransferase, ec 2.7.7.8) and rnase i (rna). the increased expression is controlled primarily by the absence of polynucleotide phosphorylase and appears to be specific for the eukaryotic ge ...1979160556
mapping and cloning of neurospora crassa mitochondrial transfer rna genes.we have obtained collections of recombinant escherichia coli plasmids containing restriction fragments of neurospora crassa mitochondrial dna cloned into pbr322. by hybridization of 32p end-labeled total mitochondrial trnas and seven different purified trnas to restriction digests of mitochondrial dna and of recombinant plasmids carrying specific restriction fragments, we have located the trna genes on the mitochondrial dna. we have found that the mitochondrial trna genes are present in two majo ...1979159308
a study of the organisation of the ribosomal ribonucleic acid gene cluster of neurospora crassa by means of restriction endonuclease analysis and cloning in bacteriophage lambda.1. total neurospora crassa dna was restricted with endonucleases and fragments carrying rrna coding sequences were identified by hybridization with xenopus laevis ribosomal dna probes. 2. the repeating unit of the rrna gene cluster was found to be 8.6 kbp, arranged in a head-to-tail fashion. 3. digestion with hind iii yielded fragments of 3.4 kbp and 5.2 kbp and both were cloned. 4. digestion with eco ri yielded fragments of 2.2 kbp, 3.0 kbp and 3.4 kbp; the 3.0 kbp fragment was cloned. 5. seque ...1979158122
metabolic activations of dimethylnitrosamine by male and female mice and rats to metabolites mutagenic in neurospora crassa. 1979158139
efficient transformation of neurospora crassa by utilizing hybrid plasmid dna.an efficient transformation system has been developed for neurospora crassa that uses spheroplasts and pvk88 plasmid dna. pvk88 is a recombinant escherichia coli plasmid carrying the n. crassa qa-2(+) gene which encodes catabolic dehydroquinase (3-dehydroquinate hydro-lyase, ec 4.2.1.10) and is part of the qa gene cluster. the recipient strain carries a stable qa-2(-) mutation and an arom-9(-) mutation, thus lacking both catabolic and biosynthetic dehydroquinase activities. transformants were se ...1979159454
mutants of neurospora deficient in nicotinamide adenine dinucleotide (phosphate) glycohydrolase.a new screening technique has been developed for the rapid identification of neurospora crassa mutants that are deficient in nicotinamide adenine dinucleotide glycohydrolase (nadase) and nicotinamide adenine dinucleotide phosphate glycohydrolase (nadpase) activities. using this procedure, five single-gene mutants were isolated whose singular difference from wild type appeared to be the absence of nad(p)ase (ec 3.2.2.6). all five mutants were found to be genetically allelic and did not complement ...1975165174
characterization of variant neurospora crassa mitochondrial dnas which contain tandem reiterations.two variant mtdna types ((types iia and hi-10) have been identified in individual subcultures of the extra-nuclear [poky] mutant of neurospora crassa. eco ri digests of type iia mtdna are characterized by an extra band, alpha, mr = 1.4 mdal, which arises from tandemly inserted reiterations of a 1.4 mdal sequence. restriction enzyme analysis and southern hybridization experiments show: that the 1.4 mdal repeats are located at the junction of eco ri-4 and -6, that the repeats contain sequences ord ...1979160287
the influence of amino acid substitutions on the conformational energy of cytochrome c.conformational energies have been evaluated for each of the staggered side-chain conformations associated with the 261 amino acid substitutions known to occur among 60 eucaryotic species. at least 86% of these substitutions can be sterically accommodated (one at a time) within the structure of horse-heart cytochrome c resulting from conformational energy refinement. simultaneous incorporation of all pertinent amino acid substitutions found in eight representative species into the refined horse-h ...1975169879
enzymatic determination of nonrandom incorporation of 5-bromodeoxyuridine in rat dna.secondary cultures of normal rat embryo cells were synchronized by a double thymidine block and pulsed with 10(-7) m 5-[3h]bromodeoxyuridine (brdurd) or 10(-7) m[3h]thymidine during an entire s phase (7.5 h). to examine the pattern of [3h]thymidine, dna was immediately extracted and purified at the completion of the s phase, cscl density gradient centrifugation revealed that substitution for thymine by bromouracil was less than 7%. single-strand specific nucleases obtained from aspergillus oryza ...1976133713
the pyridine nucleosidases from bacillus subtilis and neurospora crassa. isolation and structural properties. 1975170869
cell-free synthesis of the mitochondrial adp/atp carrier protein of neurospora crassa.adp/atp carrier protein was synthesized in heterologous cell-free systems programmed with neurospora poly(a)-containing rna and homologous cell-free systems from neurospora. the apparent molecular weight of the product obtained in vitro was the same as that of the authentic mitochondrial protein. the primary translation product obtained in reticulocyte lysates starts with formylmethionine when formylated initiator methionyl-trna (fmet-trnafmet) was present. the product synthesized in vitro was r ...1979159174
structural analysis of viral replicative intermediates isolated from adenovirus type 2-infected hela cell nuclei.deoxyribonucleoprotein complexes released 17 h postinfection from adenovirus type 1 (ad2)-infected hela cell nuclei were shown by electron microscopy to contain filaments much thicker (about 200 a [20 nm]) than double-stranded dna (about 20 a [2 nm]). the complexes were partially purified through a linear sucrose gradient, concentrated, and further purified in a metrizamide gradient. the major protein present in the complexes was identified as the 72,000-dalton (72k), adenovirus-coded single-str ...1978207893
cytochrome c-specific protein methylase iii from neurospora crassa.a protein methylase iii responsible for specifically methylating the cytochrome c in neurospora crassa was partially characterized by using unmethylated horse heart cytochrome c as a substrate. this enzyme utilizes s-adenosyl-l-methionine as the methyl donor. an analysis of the distribution of [14c]methyl groups in the peptides obtained by chymotrypsin digestion of the enzymically methylated cytochrome c showed that all of the radioactivity could be recovered within a single peak after chromatog ...1977196592
is the mitochondrially made subunit 2 of cytochrome oxidase synthesized as a precursor in neurospora crassa? 1979228973
[effect of liver chromatin dnase on closed circular dna of pm-2 phage and simian virus 40].comparative effect of the dnase from rat liver chromatin and neurospora crassa endonuclease s1 on closed circular superhelical dna of pm-2 phage and simian virus 40 is studied. it is shown that both of them--the dnase from chromatin proteins and endonuclease s1--are specific to single-stranded regions in dna molecular. it is suggested that chromatin protein dnase participates in reparation processes.1977196682
nicotinamide 3,n4-ethenocytosine dinucleotide, an analog of nicotinamide adenine dinucleotide. synthesis and enzyme studies.a structural analog of nad+, nicotinamide 3,n-4ethenocytosine dinucleotide (epsilonncd+), has been synthesized, characterized, and compared in activity with the natural coenzyme in several enzyme systems. the vmax and apparent km values were determined for nad+, epsilonncd+, and epsilonnad+ (nicotinamide 1, n6-ethenoadenine dinucleotide) with yeast alcohol, horse liver alcohol, pig heart malate, beef liver glutamate, and rabbit muscle lactate and glyceraldehyde-3-phosphate dehydrogenases. the vm ...1975234741
isolation of precursors of cytochrome oxidase from neurospora crassa: application of subunit-specific antibodies and protein a from staphylococcus aureus.a novel immunological procedure has been applied for the isolation of precursors of cytochrome oxidase. it involves antibodies to individual subunits of the oxidase and protein a from staphylococcus aureus linked to a sepharose support. unassembled (free) 'subunits' as well as a labile complex containing five polypeptide components of the oxidase were isolated from mitochondrial extracts by this technique. the procedure is superior to the previously used double-immuno-precipitation method, becau ...1978213273
kinetic studies on the specificity of chelate-iron uptake in aspergillus.three strains of the fungus aspergillus, aspergillus quadricinctus (e. yuill), a. fumigatus (fresenius), and a. melleus (yukawa), each producing different iron-chelating compounds during iron-deficient cultivation, were used for 55fe3+ uptake measurements. iron from chelates of the ferrichrome-type family was taken up by young mycelia of all strains tested, irrespective of the ferrichrome-type compound these strains predominantly produce in low-iron cultures. ferrichrysin-producing strains, howe ...19751099079
[studies on the conidial differentiation of "neurospora crassa" vi.--functional anomalies of the conditional aconidial mutant "amycelial" (author's transl)].studies using the morphological mutant "amycelial"--a conditional, aconidial strain of n. crassa--have revealed certain consistent functional and biochemical differences from wild type strains showing normal morphology and conidia formation. thus it was found that the mutant strain showed an abnormal utilization of protein reserves at a time when there is extensive degradation during conidiogenesis in wild type. in addition, the mutant exhibited abnormally low oxygen consumption and free amino a ...1975173223
introduction. membrane transport of peptides.carrier-mediated membrane transport of small peptides is now realized to be a process of wide biological distribution, occurring not only in the small intestine and elsewhere in the animal body but also in bacteria, yeast, the mould neurospora crassa, and probably in higher plants during the germination of seeds. the important features of peptide transport are outlined, and possible relationships between peptide transport and hydrolysis are discussed. peptide transport is a stereochemically spec ...1977244390
studies on the transcription complex of escherichia coli rna polymerase.to study the chain elongation phase of enzymatic rna synthesis ternary transcription complexes with t7 dna or poly[da) - (dt)] as template were isolated by gel exclusion chromatography. the dna in these complexes contains single-stranded regions which are recognized by a single-strand-specific nuclease from neurospora crassa. the non-codogenic dna strand in the poly[(da) - (dt)] ternary complex is preferentially hydrolysed by the nuclease. the polymerase protects predominantly the codogenic stra ...1977336358
the acu-1 gene of coprinus cinereus is a regulatory gene required for induction of acetate utilisation enzymes.we have isolated a gene from coprinus cinereus which cross-hybridises to the faca and acu-5 genes of aspergillus nidulans and neurospora crassa, respectively. these genes encode acetyl-coa synthetase, an enzyme which is inducible by acetate and required for growth on acetate as sole carbon source. we have designated the c. cinereus gene acs-1 and have used transformation to demonstrate its functional homology to the ascomycete genes by complementation of an n. crassa acu-5 mutation. the acs-1 ge ...19921354839
crystalline inducible kynureninase of neurospora crassa. 1976136367
genetic control of radiation sensitivity and dna repair in neurospora.radiation sensitivity in the fungus neurospora crassa is under the control of at least eight distinct loci and is also affected by cytoplasmic factors. although radiation-sensitive mutants which affect inter- or intragenic meiotic recombination have not been isolated, mutants which are defective in the repair of pyrimidine dimers have been found. evidence from both mutational and biochemical studies shows that neurospora has an excision-repair system for pyrimidine dimers which is very similar t ...19751103873
rapid rna sequencing: nucleases from staphylococcus aureus and neurospora crassa discriminate between uridine and cytidine.using end-labelled rna, significant changes in base specificity of three nucleases have been detected under defined conditions. staphylococcus aureus nuclease at ph 3.5 without ca++ cleaves all pyr-n bonds more uniformly and efficiently than rnase a, without any preference for pyr-a bonds. at ph 7.5 in 10 mm ca++ this enzyme cleaves all n-c and n-g bonds slowly, whereas n-u and n-a bonds are hydrolyzed rapidly. hence, the base at the 3'- or at the 5'-side of a phosphodiester bond can determine t ...1979158747
cytochrome c oxidase subunits in nuclear and extranuclear cytochrome-aa3-deficient mutants of neurospora crassa.the mitochondria of cytochrome-aa3-deficient neurospora crassa mutants were screened for the seven polypeptide constiuents of cytochrome c oxidase. the polypeptides of the holoenzyme and the unassembled or partially assembled subunits were detected by sodium dodecyl sulfate/acrylamide gel electrophoresis of immunoprecipitates obtained with antiserum to the holoenzyme as well as to several individual subunits. with respect to the mitochondrially synthesized polypeptides of the oxidase, subunits 1 ...1979223848
site of cleavage of superhelical phix174 replicative form dna by the single strand-specific neurospora crassa endonuclease.experiments with the neurospora crassa single strand-specific endonuclease have provided evidence for the existence of regions of partially single-stranded character in covalently closed superhelical replicative form dna of phix174. the nuclease converts the superhelical molecules to either singly hit relaxed circular or doubly hit linear molecules. we show that the initial cleavage of phix174 superhelical dna is a "nick" bounded by a 5'-phosphate and a 3'-hydroxyl; no nucleotides are excised as ...1976942717
ca(2+)-dependent ubiquitination of calmodulin in yeast.recently we were able to show that calmodulin from vertebrates, plants (spinach) and the mold neurospora crassa can be covalently conjugated to ubiquitin in a ca(2+)-dependent manner by ubiquityl-calmodulin synthetase (ucam-synthetase) from mammalian sources [r. ziegenhagen and h.p. jennissen (1990) febs lett. 273, 253-256]. it was therefore of high interest to investigate whether this covalent modification of calmodulin also occurs in one of the simplest eukaryotes, the unicellular saccharomyce ...19921309706
repair of daughter strand gaps in nascent dna from mouse epidermal cells treated with dihydrodiol epoxide derivatives of benzo[a]pyrene.alkaline sucrose gradient analysis of [methyl-3h]thymidine-pulse-labeled dna was used to study the effect of (+/-)-7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (benzo[a]pyrene-diol epoxide i), a potent mutagen and carcinogen, and (+/-)-7 beta,8 alpha-dihydroxy-9 beta,10 beta-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (benzo[a]pyrene-diol epoxide ii), a weaker mutagen and carcinogen, on the size of newly synthesized dna in primary cultures of mouse epidermal cell ...1979508766
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