PMID(sorted descending)
phenotypic diversity among alleles at the per-1 locus of neurospora crassa.comparison of 11 perithecial color mutants suggested that all were alleles at the per-1 locus but nonetheless separable into two groups because of phenotypic differences. three of the mutant strains produced orange perithecia and black ascospores, and eight produced paler, yellow perithecia and white ascospores. perithecial phenotype was dependent upon the genotype of the protoperithecial parent; ascospore phenotype, upon the genotype of the individual ascospore. no evidence was found that the w ...1976131733
developmental regulation of nicotinamide adenine dinucleotide (phosphate) glycohydrolase in neurospora crassa. 1976131723
regulation of rna synthesis in neurospora crassa. an analysis of a shift-up. 1976131689
enrichment for auxotrophic and heat-sensitive mutants of neurospora crassa by tritium suicide.tritium suicide is shown to be an effective technique for mutant enrichment in neurospora crassa. when mutagenized conidia were labelled to a high specific radioactivity either with a tritiated amino acid mixture or with [5-3h]uridine at a non-permissive temperature and stored at 4 degrees c to accumulate decays, there was a 13-15 fold enrichment for temperature-sensitive mutants relative to the original mutagenized cultures. for a wild type culture of neurospora crassa labelled with [5-3h]uridi ...1976131249
characterization of a mutant of neurospora crassa sensitive to l-tyrosine. 1976131178
biochemical and genetic studies on galactosamine metabolism in neurospora neurospora, galactosamine can be released from the cell wall and from an alcohol-soluble compound by acid hydrolysis. all of the detectable alcohol-soluble galactosamine was present as uridine diphospho-2-acetamido-2-deoxy-d-galactose (udpgalnac). the results of pulse-labeling studies and enzymatic assays indicated that udpgalnac was synthesized via the epimerization of uridine diphospho-2-acetamido-2-de+xy-d-glucose (udpglcnac). a single-gene morphological mutant, doily (do), which grew at l ...1976131123
effect of ammonium ions on the induction of nitrite reductase in neurospora crassa.results with strain am-la, a glutamate dehydrogenaseless mutant, showed that ammonium ions must first be metabolized in order to repress nitrite reductase in neurospora.1976131122
cyanide-resistant respiration of a neurospora crassa membrane mutant.choline starvation of the neurospora crassa chol-1 mutant leads to a decrease in respiration through the cytochrome chain and a concomitant induction of the alternate oxidase.1976131120
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
[anticonidiogenic effect of hydroxyurea on neurospora crassa].conidiation induced in a low sugar-ammonium medium (or by other means such as full starvation or heat shock) is almost fully prevented by hydroxyurea. in a parallel manner the dna/rna and dna/protein ratios are prevented from increasing.1976130992
"action potentials" in neurospora crassa, a mycelial fungus.occasional spontaneous "action potentials" are found in mature hyphae of the fungus neurospora crassa. they can arise either from low-level sinusoidal oscillations of the membrane potential or from a linear slow depolarization which accelerates into a rapid upstroke at a voltage 5-20 mv depolarized from the normal resting potential (near-180 mv). the "action potentials" are long-lasting, 1-2 min and at the peak reach a membrane potential near-40 mv. a 2-to 8-fold increase of membrane conductance ...1976130926
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
coordinate activation of a multienzyme complex by the first substrate. evidence for a novel regulatory mechanism in the polyaromatic pathway of neurospora crassa. 2002130831
neurospora crassa cytoplasmic ribosomes: cold-sensitive mutant defective in ribosomal ribonucleic acid synthesis.experiments were conducted to characterize further the biochemical defects of crib-1 (pj30201), a coldsensitive mutant strain of neurospora crassa with a defect in ribosome biosynthesis. the results are as follows. (i) the critical temperature for the expression of the mutant growth and ribosome phenotypes is in the range of 18 to 20 c. (ii) no preferential breakdown of 37s cytoplasmic ribosomal subunits synthesized by crib-1 at 25 c occurs after a shift to 10 c. (iii) ribosomal subunits synthes ...1976130375
regulation of thymidine metabolism in neurospora crassa.the utilization of thymidine by neurospora crassa is initiated by the pyrimidine deoxyribonucleoside 2'-hydroxylase reaction and the consequent formation of thymine and ribose. thymine must then be oxidatively demethylated by the thymine 7-hydroxylase and uracil-5-carboxylic acid decarboxylase reactions. this article shows that the 2'-hydroxylase reaction can be regulated differently than the oxidative demethylation process and suggests that the 2'-hydroxylase has, in addition to the role of sal ...1976130374
recombination in the am gene of neurospora crassa--a new model for conversion polarity and an explanation for a marker is argued that polarised intragenic recombination is not necessarily due to hybrid dna extending into the gene for variable distances from one side; it can as well be explained by hybrid dna usually covering the whole gene, the two complementary dna strands of the gene having unequal chances of undergoing the interchromatid transfer involved in hybrid dna formation, and excision from base-pair mismatches proceeding predominantly in one chemical direction (perhaps 5' to 3'). this alternative m ...2002130365
laminarinases of neurospora crassa : part ii. isolation, purification and characterization. 1975130339
regulation of cyanide-insensitive respiration in neurospora.1. inhibition of either mitochondrial transcription or translation in neurospora crassa results in the rapid production of the cyanide-insensitive pathway of mitochondrial respiration. protein synthesis on cytoplasmic ribosomes is required for the appearance of cyanide-insensitive respiration in the culture. 2. removal of the inhibition of transcription of translation results in a rapid return to cyanide-sensitive respiration. additional protein synthesis in the cytoplasm is required for the los ...1976130238
a high molecular weight dihydro-orotate dehydrogenase of neurospora crassa. purification and properties of the enzyme.some of the unusual molecular and catalytic properties of a high molecular weight dihydro-orotate dehydrogenase (dhod) from neurospora crassa have been determined. comparison of the properties of this enzyme with the properties of the soluble biosynthetic enzyme of prokaryotes has revealed several important differences. the fungal enzyme is located in a mitochondrial membrane in a position consistent with linkage with the respiratory chain through ubiquinone (miller, r. w.: arch. biochem, biophy ...1975130199
determination of total choline in biological materials.a microbiological eight-point parallel line assay for the determination of choline has been developed, using neurospora crassa cholineless-1 as test organism. in the common procedure the mold is grown at 25 degrees c in 25 ml basal medium at ph 5.9-6.0. growth studies showed, however, that a better log dose-response curve, with respect to the linear part of the curve, was obtained when the organism was grown at 30 degrees c, in 20 ml experimental volume and at ph 5.5. the proprosed eight-point a ...2002129440
isolation and characterization of a mitochondrially synthesized polypeptide from neurospora crassa cni-1 mutant.a polypeptide with a molecular weight of 8 500 (hp 8 500) was isolated from the mitochondrial membrane of the nuclear mutant cni-1 of neurospora crassa. this mutant is characterized by a cyanide-insensitive respiration and by a deficiency in the cytochromes aa3 and b. the polypeptide is synthesized on mitochondrial ribosomes. it has an extremely hydrophobic character; it is insoluble in aqueous media in the absence of sodium dodecylsulfate and is soluble in acid chloroform/methanol. it lacks his ...1975129427
complementation analysis of linked circadian clock mutants of neurospora crassa.a fourth mutant of neurospora crassa, designated frq-4, has been isolated in which the period length of the circadian conidiation rhythm is shortened to 19. +/- 0.3 hours. this mutant is tightly linked to the three previously isolated frq mutants, and all four map to the right arm of linkage group vii about 10 map units from the centromere. complementation tests suggest, but do not prove, that all four mutations are allelic, since each of the four mutants is co-dominant with the frq+ allel--i.e. ...1976129346
increase of enzyme activities in neurospora crassa during incubation at low temperatures.the effect of lowering the incubation temperature of sucrose-grown cultures of neurospora crassa on the level of various enzyme activities was investigated. of twelve inducible/derepressible activities studied, three, in addition to glycerol kinase, were found to increase during 48 h of incubation at 4-6 degrees c: trehalase (increase in specific activity of 3-10-fold), beta-glucosidase (6-12-fold) and beta-n-acetylglucosaminidase (4 to 6-fold). the maximum increases occurred at 6 degrees c and ...1976129162
differential inhibition of branching enzyme in a morphological mutant and in wild type neurospora. influence of carbon source in the growth medium.1. a morphological mutant of neurospora crassa, smco 9, (r2508) that exhibits colonial morphology when grown on sucrose or on maltose, showed a partial reversal of this morphology toward that of the wild type when it was grown on potato starch or on isomaltose. 2. a common feature of both potato starch and isomaltose is the presence of alpha-1, 6 glucosidic linkages. this suggested that these morphological effects might be due to differences in alpha-1,4 glucan: alpha-1,4 glucan 6 glycosyltransf ...1976129159
mutagenic evaluation of antischistosomal drugs and their derivatives in neurospora crassa.the mutagenic activities of lucanthone, hycanthone, niridazole, and the indazole analogs of lucanthone (ia-3 and ia-5) or hycanthone (ia-4 and ia-6) were studied by assaying for the induction of specific locus mutations in the ad-3 region of n. crassa. the results show that lucanthone, hycanthone, and their indazole analogs (ia-3 through ia-6) are all mutagenic in n. crassa when conidia are treated with any of these compounds. on a per mole basis, hycanthone is the least toxic and mutagenic, whe ...1975128637
biogenesis of mitochondrial membranes neurospora crassa during cellular differentiation: ultrastructural changes accompanying differentiation.the ultrastructural characteristics of neurospora cells during dedifferentiation and redifferentiation of conidiospores into vegetative cells have been determined. this germination process occurs between 2 and 5 h after inoculation; by 3-5 h, approximately 50% of the cells have germinated. the cells enter the exponential phase of dry-weight gain between 4 and 5 after inoculation. several unusual structures are observed in neurospora cells during germination. whorled structures are frequently see ...1976128616
biogenesis of mitochondrial membranes in neurospora crassa during cellular differentiation: ultrastructural changes accompanying differentiation.the ultrastructural characteristics of neurospora cells during dedifferentiation and redifferentiation of conidiospores into vegetative cells have been determined. this germination process occurs between 2 and 5 h after inoculation; by 3-5 h, approximately 50% of the cells have germinated. the cells enter the exponential phase of dry-weight gain between 4 and 5 h after inoculation. several unusual structures are observed in neurospora cells during germination. whorled structures are frequently s ...1976128615
biogenesis of mitochondrial membranes in neurospora crassa during cellular differentiation: changes in oxidative phosphorylation and synthesis of mitochondrial phospholipids.changes in the capacity of mitochondria to carry out oxidative phosphorylation and in the rate of synthesis and incorporation of phospholipids into mitochondria were measured during the germination of conidiospores of neurospora crassa. the competence of isolated mitochondria to carry out coupled respiration was very low during the first 3 h growth, but it increased rapidly, reaching maximal levels at 5 to 6 h growth. changes in mitochondrial function were the same in cells grown in 2% sucrose- ...1976128614
morphology and growth kinetics of hyphae of differentiated and undifferentiated mycelia of neurospora crassa.a comparison was made of the morphology and growth kinetics of hyphae of differentiated and undifferentiated mycelia of neurospora crassa. undifferentiated mycelia were formed during exponential growth on solid media or submerged culture. hyphae at the margin of differentiated mycelia (colonies) differed from undifferentiated mycelia in diameter, extension rate, extension zone length, and intercalary and apical compartment length. the mean hyphal extension rate (e) of an undifferentiated myceliu ...1975128613
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
synthesis of polyadenylic acid-containing ribonucleic acid during the germination of neurospora crassa conidia.ribonucleic acid (rna) synthesized during the first 1 h of conidial germination (15 to 20, 25 to 30, and 55 to 60 min) has been characterized by sucrose-sodium dodecyl sulfate gradient centrifugation, binding to polyuridylic acid filters, and oligo(dt)-cellulose chromatography. at all labeling periods examined, polyadenylic acid-containing rna is synthesized, processed, and incorporated into polysomes. approximately 40% of the labeled rna sedimenting between 5 and 17s binds to polyuridylic acid ...1976128551
adaptive significance of vegetative incompatibility in neurospora crassa.certain features reminiscent of sexuality occur in the vegetative life cycle of some filamentous fungi such as neurospora crassa. hyphal fusions can occur between genetically different individuals, thereby endowing the new composite mycelium, a heterokaryon, with some of the advantages of heterozygosity usually associated with diploid organisms. in n. crassa, however, there are a number of incompatibility loci which prevent formation of heterokaryons unless the alleles at the incompatibility loc ...1975128487
escape from mating-type incompatibility in bisexual (a + a) neurospora neurospora crassa, strains of opposite mating type generally do not form stable heterokaryons because the mating type locus acts as a heterokaryon incompatibility locus. however, when one a and one a strain, having complementing auxotrophic mutants, are placed together on minimal medium, growth may occur, although the growth is generally slow. in this study, escape from such slow growth to that at a wild type or near-wild type rate was observed. the escape cultures are stable heterokaryons, m ...1975128407
phosphocellulose, an affinity chromatographic system for chorismate synthase and the aromatic complex of neurospora crassa. 2002128358
gene topography and function. i. gene expression in germinating conidia of neurospora an attempt to find clues for the significance of the gene ordering along the eukaryotic chromosome, a system consisting of germinating conida of neurospora crassa was studied. thirteen enzyme activities corresponding to genes widely distributed on five chromosomes were determined in dormant and in germinating conidia. ten of these enzymes showed lower activities in the resting state, and the time patterns of their increase were determined during germination. the results obtained do not suppor ...2002128350
specificity and regulation of peptide transport on neurospora crassa. 2002128318
influence of an aggregated multienzyme system on transient time: kinetic evidence for compartmentation by an aromatic-amino-acid synthesizing complex of neurospora crassa.the aromatic complex of neurospora crassa is an aggregated multienzyme system which catalyzes five consecutive reactions in the central pathway leading to the biosynthesis of the aromatic amino acids. in an attempt to understand the physiological importance of this complex in particular, as well as the importance of cellular organization of enzyme systems in general, we have isolated the complex and have begun to characterize its catalytic properties. optimum conditions for the assay of the over ...2002128001
proteases of neurospora crassa: their role in morphology. 2002127746
localization of enzymes in the cell walls of neurospora crassa. 2002127745
isolation and characterization of a mutant of neurospora crassa deficient in general amino acid permease activity.a mutant of neurospora crassa (pm-nbg27) was isolated on the basis of its resistance of p-fluoro-phenylalanine on ammonium-deficient vogel's medium. this mutant was found to be devoid of both conidial and post-conidial (after 180 min of preincubation) transport activity of all amino acids. genetic analysis of pm-nbg27 by crossing it to wild-type (74a) resulted in the predicted segregants exhibiting transport characteristics of pm-n, pm-b, pm-g, pm-nb, pm-ng, pm-bg and parental types. the above o ...2002127619
enzymes of neurospora crassa which attack uv-irradiated dna.two excision-deficient mutants of neurospora crassa contain normal levels of two enzymes, a single-strand-specific exonuclease and a single-strand specific endonuclease, which attack uv-irradiated dna. mutants of n. crassa have been obtained in which the activity of the latter enzyme as well as an activity with native dna are simultaneously affected. these activities are also apparently low in excision-proficient uvs3 strain of n. crassa which has many of the characteristics of the reca mutants ...2002127578
sex-hormones in neurospora crassa. renewed evidence for their specificity (to "male sterility" of the a mating type). 1975127489
[repression of urease biosynthesis in neurospora crassa by ammonium ions].the regulation of the synthesis of the enzyme urease (urea amido hydrolase e.c. in neurospora crassa was investigated. the biosynthesis of urease is repressed by ammonium ions. under ammonium excess conditions the specific activity of urease decreases from 0.980 to 0.180 mumoles nh3/min/mg protein. by addition of cycloheximide it was shown that ammonia influences the synthesis of this enzyme. enzyme induction by the substrate could be excluded. even under the conditions of highest repr ...2002127430
induced transfer of higher plant chloroplasts into fungal protoplasts.chloroplasts isolated from spinach leaves have been transferred in large numbers into protoplasts of neurospora crassa with the help of polyethylene glycol. the chloroplasts show high photosynthetic activity--at least until the time of uptake--and the protoplasts continue to show active cytoplasmic streaming after chloroplast uptake.2002127380
arrangement of sequences in the inverted terminal repetition of adenovirus 18 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
influence of light on the inhibition of neurospora crassa growth by the antibiotic edeine. 1975127125
rapid loss of a novel phenylalanyl-trna on germination of neurospora crassa conidia. 1975127124
siroheme: a prosthetic group of the neurospora crassa assimilatory nitrite reductase.the neurospora crassa assimilatory nitrite reductase (ec catalyzes the nadph-dependent reduction of nitrite to ammonia, a 6-electron transfer reaction. highly purified preparations of this enzyme exhibit absorption spectra which suggest the presence of a heme component (wavelength maxima for oxidized senzyme: 390 and 578 nm). there is a close correspondence between nitrite reductase activity and absorbance at 400 nm when partially purified nitrite reductase preparations are subjected to ...2002126995
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
the interactive effect of ultraviolet irradiation and 5-bromouracil at the rib-1 locus in neurospora crassa.5-bromouracil (5-bu) was shown to enhance reverse mutation rates when added to conidia of a rib-1 strain of neurospora crassa previously irradiated with ultraviolet light. a comparison is presented between various incubation intervals in the presence and absence of 5-bu while varying the uv dose. an increase in mutation frequency ranging from 0.028 - 2.05 x 10(2) times greater than the spontaneous frequency, uv frequency alone or 5-bu frequency alone was observed when uv irradiation and 5-bu wer ...2002126795
growth patterns of adenine-3b; supersuppressor strains of neurospora crassa.the interaction between several suppressible ad-3b alleles and several supersuppressor genes had been examined both quantitatively and qualitatively in a tetrad analysis. quantitatively, there is a good deal of variation in mean growth rates of cultures showing supersuppression: part of this variation can be attributed to variation in the suppressibility of ad-3b alleles, part to variation of suppression efficiency of ssu alleles, and part to the action of modifying genes. qualitatively, ad-3b; ...2002126794
a kinetic study of thymine 7-hydroxylase from neurospora crassa.the steady-state kinetics of thymine 7-hydroxylase (thymine, 2-oxoglutarate dioxygenase, ec has been investigated. initial velocity plots were all found to be linear and intersecting. variation in concentration of two of the substrates, when the third substrate was at a constant high or low concentration, gave initial velocity plots that conform to an ordered sequential mechanism, where thymine is the second substrate to add. with 5-carboxyuracil, which is the end product in the seque ...2002126696
biochemical genetic studies of cycloheximide resistance in neurospora crassa.genetic analysis of a number of cycloheximide-resistant mutants of neurospora crassa has shown that resistance is controlled by several genes. two of these appear to be located on linkage group v. resistance to the antibiotic is dominant in wild-type-mutant heterokaryons. two types of cycloheximide-resistant mutants were isolated: one type exhibited colonial morphology only when grown in the presence of cycloheximide and the other type maintained normal morphology even at high concentrations of ...2002126683
occurrence in wild strains of neurospora crassa of genes controlling genetic recombination.each of the main laboratory wild stocks of n. crassa carries one of two alleles at the rec-1 and rec-2 loci and one of three at the rec-3 locus. the constitutions of the stocks are given in fig. 1. some of those conserved are evidently not the originals. the third rec-3 gene (rec-3l), found in lindegren a, controls recombination at the am-1 locus to a level between that of rec-3+ and rec-3, the relative levels being 1 : 8 : 25. at the his-2 locus rec-3l is indistinguishable from rec-3+ in its le ...2002126680
freeze-etch and thin section studies of neurospora crassa ascospores. 1975126461
genetic and metabolic control of the purine catabolic enzymes of neurospora crasse.neurospora crassa can utilize various purine bases such as xanthine or uric acid and their catabolic products as a nitrogen source. four classes of mutants which affect the purine degradative pathway were isolated and studied. mutants of the aln-1 class specifically lack allantoinase, while alc-1 mutants lack allantoicase. mutants designated as xdh-1 cannot utilize hypoxanthine as a nitrogen source and are presumed to be deficient in xanthine dehydrogenase activity. a regulatory mutant, amr, was ...1975126363
oscillations of an electrogenic pump in the plasma membrane of neurospora.the presence of the poky mutation in neurospora crassa produces mitochondria which are defective in cytochromes b and aa3 but which compensate by means of an alternate, cyanide-insensitive oxidase. as previously reported (slayman, rees, orchard & slayman, j. biol. chem., 250:396, 1975) cyanide blockade of the poky strain carrying the partial suppressor f results in a metabolic downshift of only 56%, compared with a downshift of 98% in wild-type neurospora; the downshift is accompanied by exponen ...1975126326
glycerophospholipid variation in choline and inositol auxotrophs of neurospora crassa. internal compensation among zwitterionic and anionic species.the glycerophospholipids of cultures of neurospora crassa were extracted, deacylated, and analyzed. in addition to a wild-type strain, several auxotrophic mutant strains were examined: chol-1 (defective s-adenosylmethionine: phosphatidylethanolamine methyltransferase), chol-2 (defective s-adenosyl methionine:phosphatidylmonomethylethanolamine (dimethylethanolamine) methyltransferase), and inos (defective myoinositol-1-phosphate phosphatase). in addition, a double mutant strain, chol-1;chol-2, wa ...1975126231
effect of histidine on purine nucleotide synthesis and utilization in neurospora crassa.histidine affects de novo purine nucleotide synthesis and purine nucleotide pool utilization in neurospora crassa. the former effect was assessed qualitatively by the presence or absence of purple pigment production in ad3b and ad3a mutants. tryptophan also affected the de novo purine nucleotide synthesis. the effect of histidine on purine nucleotide pool utilization resulted in stimulated germination of ad8 and ad4 mutant conidia in adenine-deficient medium. increased germination was correlated ...1975126229
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
characteristics of a glycerol utilization mutant of neurospora crassa.a mutant of neurospora crassa able to grow on liquid minimal glycerol medium without evidence of conidiation and with high cell yields has been isolated and shown to be allelic to ff-1. the glycerol-specific induction of glycerokinase and glycerol-3-phosphate dehydrogenase was similar in both wild-type and mutant cells, although higher specific activities as well as higher glycerokinase cross-reacting material levels were found in fully induced mutant cells. after growth in minimal glycerol medi ...1975126227
effect of mutations in the qa gene cluster of neurospora crassa on the enzyme catabolic dehydroquinase.catabolic dehydroquinase, which functions in the inducible quinic acid catabolic pathway of neurospora crassa, has been purified from wild type (74-a) and three mutants in the qa gene cluster. the mutant strains were: 105c, a temperature-sensitive constitutive mutant in the qa-1 regulatory locus; m-16, a qa-3 mutant deficient in quinate dehydrogenase activity; and 237, a leaky qa-2 mutant which possess very low levels of catabolic dehydroquinase activity. the enzymes purified from strains 74-a, ...1975126226
purine base transport in neurospora crassa.observations presented in this paper point to the presence of dual transport mechanisms for the base adenine in neurospora crassa. competition for transport, as well as growth inhibition studies using an ad-1 auxotroph, show that the purine bases adenine, guanine, and hypoxanthine share at least one transport mechanism which is insensitive to adenosine, cytosine, and a variety of other purine base analogues. on the other hand, uptake of adenine by an ad-8 mutant strain unable to transport [8-14c ...1975126225
biogenesis of mitochondrial membranes in neurospora crassa. mitochondrial protein synthesis during conidial germination.the conidia of neurospora crassa entered logarithmic growth after a 1-h lag period at 30 degrees c. although [14c]leucine is incorporated quickly early in growth, cellular protein data indicated that no net protein synthesis occurred until after 2 h of growth. neurospora is known to produce ethanol during germination even though respiratory enzymes are present. also, neurospora mitochondria isolated from cells less than 3-h old are uncoupled. since oxygen uptake increased during germination, was ...2002126153
lipophilic proteins encoded by mitochondrial and nuclear genes in neurospora crassa.mitochondrial proteins soluble in neutral chloroform-methanol (2:1) were separated from lipids by ether precipitation and resolved by sephadex g-200 filtration in the presence of dodecylsulfate into two major fractions eluting in the excluded region (peak i) and in a region of an apparent molecular weight 8000 (peak ii). residual phospholipids are found only in peak ii. peak i consists of several aggregated small polypeptides of molecular weights around 8000, which can be disaggregated by mild o ...1975126152
denaturation map of the circular mitochondrial genome of neurospora crassa.a denaturation map of mitochondrial dna from the wild type strain 5256 of neurospora crassa was constructed by computer analysis of the contour length distribution of single- and double-stranded regions of nineteen circular and three full length linear molecules after partial denaturation. the data suggest that mitochondrial dna in this strain is a homogeneous population of a circular molecule of molecular weight 41 - 10(6) with an asymmetric distribution of at-rich regions, and that linear mole ...1975126085
conversion of d-lysine via l-pepecolic acid in neurospora crassa.neurospora crassa converts d-lysine to l-pipecolic acid and the latter to l-lysine by a pathway outlined herein and different from mechanisms hitherto known to be involved in interconversions of enantiomers of amino acids.2016125972
[possible physiological role of the "high molecular weight polyphosphate-polyphosphate phosphohydrolase" system in neurospora crassa].the biosynthesis of polyphosphatase and the system of active transport of glucose is repressed in the cells of neurospora crassa by glucose at a high concentration. there is a strict correlation between the activity of polyphosphatase and the initial rate of glucose active transport. both systems are repressed during the growth of the mycelium on a glucose medium and are repaired on a medium without glucose. the latter process is inhibited by cycloheximide. under various conditions of cultivatio ...2002125845
letter: methylation of mitochondrial rna species in the wild-type and poky strains of neurospora crassa. 2001125795
subunit structure of anthranilate synthetase from neurospora crassa.freshly purified preparations of anthranilate synthetase complex from neurospora crassa appeared to be homogeneous on polyacrylamide disc gels and were composed of two distinct subunits, 94,000 and 70,000 daltons, respectively, as determined by electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate. carboxymethylation of the complex or treatment with guanidine hydrochloride and urea before sodium dodecyl sulfate treatment did not alter the subunit pattern. when the puri ...2001125757
conidiation of neurospora crassa induced by treatment with natrium fluoride in submerged culture.a transient treatment of pregerminated conidia of neurospora crassa with naf induced young, submerged cultures to prematurely differentiate conidia. the inductive treatment decreased the rate of respiration (with lower rq), reduced the relative concentration of nucleoside triphosphates, and inhibited leucine incorporation into protein and adenosine incorporation into rna.2001125568
death resulting from unbalanced growth in a temperature-sensitive mutant of neurospora crassa.a temperature-sensitive mutant of neurospora crassa was found to undergo rapid death on minimal medium at 35 degrees c. the loss of viability in this mutant was prevented by various factors which retard growth, including deprivation of carbon sources or interruption of protein synthesis. synthesis of nucleic acids and protein in this mutant was normal at the early stages of germination and then depressed at 35 degrees c. the active transport of glucose and the respiration rate in this mutant wer ...2001125567
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
purification and characterization of catabolic dehydroquinase, an enzyme in the inducible quinic acid catabolic pathway of neurospora crassa.catabolic dehydroquinase which functions in the inducible quinic acid catabolic pathway in neurospora crassa has been purified 8000-fold. the enzyme was purified by two methods. one used heat denaturation of contaminating proteins; the other used antibody affinity chromatography. the preparations obtained by these two methods were identical by all criteria. the purified enzyme is extremely resistant to thermal denaturation as well as denaturation 0y urea and guanidine hydrochloride at 25 degrees ...1975125280
enzymatic and non-enzymatic reduction of nitrite by extracts of neurospora crassa.two activites causing nitrite disappearance are found in extracts of neurospora; one, inducible by nitrate or nitrite and present only in nitrite-utilizing strains, catalyze the stoichiometric reduction of nitrite to ammonia; the other, present in all strains under all conditions, causes the disappearance of nitrite to something other than ammonia. the latter activity has a molecular weight of about 600 and may contain an oligopeptide, a metal, and an sh group(s). it has no known physiological f ...2001125270
size restriction on utilization of peptides by amino acid auxotrophs of neurospora crassa.growth of an amino acid auxotroph of neurospora crassa on oligopeptides is shown to occur by extracellular hydrolysis, with subsequent utilization of monomer amino acid residues, and by transport of peptides. peptides with a hydrodynamic volume greater than that of trileucine are not transported, and this lack of transport is shown to be due to restriction by the oligopeptide transport system rather than the cell wall.1975125269
microbial transformation of artificial estrogens of the allenolic group.when 2,2-dimethyl 3-(2'-naphthyl 6'-hydroxy) pentanoic acid, an artificial estrogen of the allenolic acid group, was added to an exponential-phase growth culture of neurospora crassa (in horowitz medium), it was transformed into its hydroxylated derivative, 2,2-dimethyl 3-(2'-naphthyl 4',6'-dihydroxy)pentaoic acid. to study this transformation, radioactive 2-methyl-[2-14-c=a1methyl 3-(2'-naphthyl 6'-hydroxy) pentanoic acid has been prepared. the rate of metabolism of allenolic acids varies in th ...2001125267
scanning electron microscopy of surface and internal features of developing perithecia of neurospora crassa.stages in the development of perithecia of neurospora crassa, designated by the time elapsed after crossing, were investigated with the scanning electron microscope, from protoperithecia through perithecia. the usual examination of external features of whole specimens with this instrument was augmented by a freeze-fracture technique which allowed the viewing of development internally as well. rapid increases in perithecial size soon after crossing were followed by the appearance, in section, of ...2001125266
regulation of exocellular proteases in neurospora crassa: metabolic requirements of the 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
characterization of the glucose transport systems in neurospora crassa sl.neurospora crassa sl, a mutant that lacks a rigid cell wall, exhibits transport systems for glucose similar to those of wild-type strain 1a. when the orgnism is grown in a medium containing 50 mm glucose as the carbon source, glucose is transported primarily by a glucose-facilitated diffusion system (glui). when it is grown in a medium with little or no glucose present, a glucose active transport system (glu ii) is expressed. both of these systems are similar kinetically to those in the wild typ ...2001125261
developmental control of glucosamine and galactosamine levels during conidation in neurospora crassa.the glucosamine and galactosamine content of mycelia was measured in cultures of neurospora crassa grown on the surface of dialysis membranes. the glucosamine content was relatively constant throughout the different regions of the mycelial mat. the galactosamine content, however, was always lower in the growing-front region of the mycelial mat than in the older regions. at most, only low levels of galactosamine were necessary for the formation of hyphae at the growing front of a mycelial mat. th ...2001125260
changes in glucosamine and galactosamine levels during conidial germination in neurospora crassa.the levels of glucosamine and galactosamine were determined in conidia, germinating conidia, and vegetative mycelia of neurospora crassa. in the vegetative mycelia about 90% of the amino sugars were shown to be components of the cell wall. the remaining 10% of the amino sugars were tentatively identified as the nucleotide sugars uridine diphospho-2-acetamido-2-deoxy-d-glucose and uridine diphospho-2-acetamido-2-deoxy-d-galactose. conidia and vegetative mycelia contained about the same levels of ...1975125259
identification of two products of mitochondrial protein synthesis associated with mitochondrial adenosine triphosphatase from neurospora crassa.soluble mitochondrial atpase (f1) isolated from neurospora crassa is resolved by dodecylsulfate-gel electrophoresis into five polypeptide bands with apparent molecular weights of 59000, 55000, 36000, 15000 and 12000. at least nine further polypeptides remain associated with atpase after disintegration of mitochondria with triton x-100 as shown by the analysis of an immunoprecipitate obtained with antiserum to f1 atpase. two of the associated polypeptides with apparent molecular weights of 19000 ...1975125201
specific fragmentation of mitochondrial dna from neurospora crassa by restriction endonuclease eco r i. 1975125087
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
levels and rates of synthesis of ribosomal ribonucleic acid, transfer ribonucleic acid, and protein in neurospora crassa in different steady states of growth.the levels of ribosomes, trna molecules, and total protein per genome in neurospora mycelia have been determined in eight different conditions of exponential growth. by increasing the rate of growth the number of ribosomes per genome increases dramatically while the level of total protein remains almost unchanged and the level of trna increases only slightly. the rates of synthesis of each of the macromolecules have been estimated. increasing the rate of growth (mu) up to 0.5, the ratio between ...1975124730
glycerol non-utilizing mutants in neurospora crassa. isolation by net replication. 1998124714
the essentiality of sulfhydryl groups to transport in neurospora crassa. 1975124553
regulation of methionine biosythesis in neurospora crassa. 1975124550
gamma-ray inactivation of conidia from heterokaryons of neurospora crassa containing uv-sensitive mutations.two-component heterokaryons were formed with the fungus neurospora crassa. the uv-sensitive mutations upr-i, uvs-4, and uvs-6 were utilized. conidia produced by these heterokaryons were exposed to gamma-rays and survival curves were established for the three conidial fractions produced by each heterokaryon. results showed that upr-i, when included in only one nuclear component, did not affect the sensitivity of any conidial fraction; however, when included in both components, all three conidial ...1975124401
heterokaryon incompatibility genes in neurospora crassa detected using duplication-producing chromosome rearrangements.evidence is presented for five or six previously undetected heterokaryon incompatibility (het) loci, bringing to about ten the number of such genes known in neurospora crassa. the genes were detected using chromosome duplications (partial diploids), on the basis of properties previously known for het genes in duplications. duplications homozygous for het genes are usually normal in growth and morphology, whereas those heterozygous are strikingly different. the heterozygotes are inhibited in thei ...1975124287
stimulation of folate metabolism by exogenous glycine in neurospora crassa wild type. 2002124265
[isolation of a new keto-acid, produced from epsilon-n-trimethyllysine by neurospora crassa].a new epsilon-n-trimethyllysine metabolite has been isolated from the mycelium of neurospora crassa. the labelled compound produced from incubations in vivo and in vitro from epsilon-n-trimethyl ([14-c]h3)l-lysine has been identified as 2-keto-epsilon-n-trimethyl-hexanoic acid by reducing its 2,4-dinitrophenyl hydrazone back to epsilon-n-trimethyllysine by hydrogenolysis in a parr bomb. analyses on tlc and in four different ion exchange chromatographic systems show the appearance of a ninhydrin ...1975124260
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
microsomal activation of dimethylnitrosamine to metabolites mutagenic in neurospora crassa. 1975124014
6-phosphogluconate dehydrogenase from neurospora crassa. 2002124005
genetic control of phosphate-metabolizing enzymes in neurospora crassa: relationships among regulatory neurospora crassa, the phosphate-metabolizing enzymes are made during phosphate starvation, but not under phosphate sufficiency. the synthesis of these enzymes is controlled by three regulatory genes: pcon-nuc-2, preg and nuc-1, pcon-nuc-2 and preg are closely linked. a model of the hierarchical relationships among these regulatory genes is presented. studies of double mutants and revertants confirm several predictions of the model. it has been found that nuc-2 (null) and pcon-c (constitutive ...2002123873
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
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