PMID(sorted descending)
an inducible acetate transport system in neurospora crassa conidia.neurospora crassa conidia possess an active transport system for the uptake of acetate. this system was characterized as: (a) energy dependent; (b) taking place against a concentration gradient; (c) saturating at higher substrate concentrations and (d) competitively inhibited by propionate. activity of the acetate transport system can be further enhanced by preincubating conidia in 1 mm acetate medium for 180 min (the inducible transport system). the conidial system and the inducible system have ...1977144526
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. v. tryptic peptides.the isolation and sequences of an additional 80 peptides from a tryptic digest of the nad-specific glutamate dehydrogenase of neurospora crassa are reported. these include an additional peptide containing a lysine residue labeled at the epsilon-amino group with pyridoxal 5'-phosphate. the sequence of this peptide shows some homology with the reactive lysine residue of other glutamate dehydrogenases.1977144134
biosynthesis of carnitine in neurospora 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
unstable s-adenosylmethionine synthetase in an ethionine-resistant strain of neurospora crassa.a pleitropic ethionine-resistant mutant of neurospora contains an s-adenosylmethionine synthetase that is labile to heat and dialysis but exhibits normal kinetics for methionine and ethionine.1977144115
adaptive changes in phosphate uptake by the fungus neurospora crassa in response to phosphate supply.the phosphate uptake rate of neurospora crassa germlings growing exponentially in media containing phosphate at concentrations between 10 mm and 50 micronm was virtually constant. the uptake characteristics of these germlings were studied in detail assuming the simultaneous operation of two uptake systems, one of low affinity and one of high affinity. the km of the low-affinity system was constant after growth at phosphate concentrations greater than 1 mm but became progressively lower as the co ...1977144114
kinetic characterization of the two phosphate uptake systems in the fungus neurospora crassa.the kinetics of phosphate uptake by exponentially growing neurospora crassa were studied to determine the nature of the differences in uptake activity associated with growth at different external phosphate concentrations. conidia, grown in liquid medium containing either 10 mm or 50 micronm phosphate, were harvested, and their phosphate uptake ability was measured. initial experiments, where uptake was examined over a narrow concentration range near that of the growth medium, indicated the prese ...1977144113
the 73 s ribosome of neurospora crassa is the native mitochondrial ribosome. 1977143964
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 endo.r.hindiii restriction endonuclease fragments of n. crassa dna from a qa-1(c) (constitutive) mutant and of escherichia coli plasmid ...1977143663
chloramphenicol-sensitive labelling of protein in microsomes of neurospora crassa. 2003143619
role of lipids in the neurospora crassa membrane. ii. membrane potential and resistance studies; the effect of altered fatty acid composition on the electrical properties of the cell membrane.the effect of doubling the saturated fatty acid content on the electrophysiology of neurospora crassa membranes was studied. intracellular membrane input resistance (rm) and potential (em) were measured for wild-type (w/t) and cel- (tween 40) organisms as a function of temperature. over the 0 to 40 degrees c temperature range studied, mean em values of both w/t and cel- (tw 40) organisms increased from -160 to -210 mv. this difference is greater than that expected from nernst potential considera ...1977143534
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
regulation of exocellular protease in neurospora crassa: induction and repression under conditions of nitrogen starvation. 1977143241
nuclear cytochrome-deficient mutants of neurospora crassa: isolation, characterization, and genetic mapping. 1977142902
nitrogen regulation of arginase in neurospora crassa.the final products of the arginine catabolism that can be utilized as a nitrogen source in neurospora crassa are ammonium, glutamic acid, and glutamine. the effect of these compounds on arginase induction by arginine was studied. in wild-type strain 74-a, induction by arginine was almost completely repressed by glutamic acid plus ammonium, whereas ammonium or glutamic acid alone had only moderate effects. arginine products of catabolism also repressed arginase induction. a mutant, ure-1, which l ...1977142762
demonstration of specific aminopeptidase inhibitors in neurospora crassa. 1977142659
galactosyltransferase of enzyme, galactosyltransferase, able to catalyze the formation of galactose polymers was detected in cell-free extracts of a wild type strain of neurospora crassa. enzyme activity was found in both the supernatant and the particle fractions after centrifugation at 100,000 x g. the enzyme assayed in the 100,000 x g supernatant showed a 4fold difference in specific activity as compared to that found in the particle fraction.1977142643
[histones of the fungi, endomyces magnusii and neurospora crassa].histones of endomyces magnusii and neurospora crassa were found to consist of four main fractions similar to calf thymus histones in their electrophoretic mobilities, molecular sizes and chromatographic behaviour on akrilex p-60. two of them are homologous to the most conservative histones h3 and h4. other two fractions correspond to the histones h2a and h2b; however, they have some pecularities. a fraction of n. crassa histones corresponding to the h2b was isolated in a homogeneous state by mea ...1977142527
site of action of iron in the induction of delta-aminolevulinate dehydratase in neurospora crassa. 1977142484
effect of temperature and temperature shifts on growth and branching of a wild type and a temperature sensitive colonial mutant (cot 1) of neurospora crassa.growth of a temperature sensitive colonial mutant (cot 1) of neurospora crassa was compared with a wild type strain. the hyphal growth unit (the ratio between mycelial length and number of branches) of the wild type was not appreciably altered by temperature and there was a direct relationship between the specific growth rate (alpha) of these mycelia and their mean hyphal extension rate (e). the specific growth rate of cot 1 increased by about the same relative amount as the wild type between 15 ...1977142456
purification of s-adenosylmethionine: epsilon-n-l-lysine methyltransferase. the first enzyme in carnitine biosynthesis.the initial steps of carnitine biosynthesis in neurospora crassa involve the methylation of the epsilon-amino group of lysine as follows: lysine a leads to monomethyllysine b leads to dimethyllysine c leads to trimethyllysine. the methyl donor is s-adenosylmethionine. an enzyme, s-adenosylmethionine:epsilon-n-l-lysine methyltransferase, has been purified from n. crassa to near homogeneity as judged by column chromatography, polyacrylamide gel electrophoresis, and ultracentrifugation. this protei ...1977142089
developmental-stage-dependent adenine transport in neurospora crassa.although germinated conidia of neurospora crassa transport adenine through two different systems, only one of these, namely, the general purine transport system, which transports adenine, hypoxanthine, guanine, and 6-methylpurine, is present in freshly harvested conidia of the wild type. the second system develops during germination. the latter system can transport adenine and 6-methylpurine. time course and kinetic studies of adenine transport in freshly harvested conidia of an ad-8 mutant indi ...1977142082
levels of the ribonucleoside triphosphates and rate of rna synthesis in neurospora crassa.the levels of the four ribonucleoside triphosphate (atp, gtp, utp and ctp) have been determined in neurospora crassa in three conditions of exponential growth (on glucose, acetate and glycerol) as well as in the course of a shift-up and a shift-down transition of growth between two of them. although in some cases the pools appear proportional to the rate of synthesis of ribosomal rna, this seems not to be strictly dependent on the level of the nucleotides.2003141945
characterization of neurospora crassa mutant stratins deficient in adenylate cyclase activity. 1977141907
messenger ribonucleoprotein complexes isolated by oligodeoxythymidylate-cellulose chromatography from neurospora crassa polysomes.messenger ribonucleoprotein (mrnp) complexes were isolated from ethylenediaminetetraacetic acid-dissociated polysomes of neurospora crassa. approximately 15% of the [3h]uridine incorporated into polysomal ribonucleic acid (rna) during a 15-min pulse was eluted from oligodeoxythymidylate-cellulose as an mrnp complex. the isolated mrnp complexes exhibited sedimentation coefficients ranging from 15s to greater than 60s. rna isolated from these mrnp complexes sedimented in sucrose gradients between ...1977141447
composition and synthesis of cellular lipids in neurospora crassa during cellular differentiation.the synthesis of cellular lipids of neurospora crassa was measured during growth on low (2% sucrose)- and high (15% glucose)-carbohydrate supplementation. the amount of lipid per dry weight of cells does not change during the germination and early logarithmic growth periods, but the percentage of phospholipid in the lipid does increase, reaching a maximal value of 90% at 4 to 5 h after inoculation, at which time the phospholipid content of the cells is approximately 60 mumol/g (dry weight). the ...1977141445
characterization of the new osmotic mutants (os) which originated during genetic transformation in neurospora crassa. 1977141392
dna syntheses in course of meiotic development in neurospora crassa. 1977141391
heterogeneous base distribution in mitochondrial dna of neurospora crassa.the mitochondrial dna of neurospora crassa has a heterogeneous intramolecular base distribution. a contiguous piece, representing at least 30% of the total genome, has a g+c content that is 6% lower than the overall g+c content of the dna. the genes for both ribosomal rnas are contained in the remaining, relatively g+c rich, part of the genome.1977141040
a temperature-sensitive mutant of neurospora crassa deficient in cytochrome b.a nuclear gene mutant of neurospora crassa designated cyb-3 is deficient in cytochrome b and coenzyme qh2-cytochrome c reductase. nearly normal when grown at 25 degrees c, the strain expresses a mutant phenotype at 38 degrees c. mitochondria from cyb-3 mycelium, which has undergone 3-4 mass doublings at the elevated temperature, possess 3-fold less cytochrome b, 2-fold more cytochrome, c, 5-fold less coenzyme qh2-cytochrome c reductase activity, and require 3-fold less antimycin a per milligram ...1977141003
characterization and in vitro translation of polyadenylated messenger ribonucleic acid from neurospora crassa.ribonucleic acid (rna) extracted from neurospora crassa has been fractionated by oligodeoxythymidylic acid [oligo(dt)]-cellulose chromatography into polyadenylated messenger rna [poly(a) mrna] and unbound rna. the poly(a) mrna, which comprises approximately 1.7% of the total cellular rna, was further characterized by sepharose 4b chromatography and polyacrylamide gel electrophoresis. both techniques showed that the poly(a) mrna was heterodisperse in size, with an average molecular weight similar ...1977140861
unsaturated fatty acid mutants of neurospora crassa.unsaturated fatty acid (ufa) auxotrophs of neurospora crassa were obtained by treatment of conidia with n-methyl-n'-nitro-n-nitrosoguanidine followed by isolation on media containing polyunsaturated fatty acids suspended in tergitol np-40. the 24 mutants for which reisolates were obtained from crosses with wild type were assigned to two complementation classes, ufa-1 and ufa-2, located on linkage group v. unsaturated fatty acids with varying degrees of unsaturation, chain length, and double-bond ...1977140860
nuclear suppressors of the (poky) cytoplasmic mutant in neurospora crassa. ii. mitochondrial cytochrome systems.the mitochondrial cytochrome aa3 and b deficiencies of the [poky] cytoplasmic mutant of neurospora crassa are partially suppressed by mutant alleles of any one of six nuclear genes, namely sup-1, sup-3, sup-4, sup-5, sup-10 and sup-14. the suppressor-induced increases in the concentration of both cytochromes are detected in the mitochondria from exponentially growing [poky] cultures, and, thus, are clearly distinguishable from the age-dependent changes in the cytochrome system that occur in cult ...2003140757
the molecular basis of an osmotically reparable mutant of neurospora crassa producing unstable glutamate dehydrogenase. 2003140246
role of lipids in the neurospora crassa membrane. i. influence of fatty acid composition on membrane lipid phase transitions.the relationship between lipid composition and phase transition was investigated by differential scanning calorimetry for intact and membrane phospholipid extracts of wild-type (w/t) and the cel-(tw 40) mutant of neurospora crassa. the cel-(tw 40) mutant (grown on minimal, sucrose medium supplemented with tween 40 at approximately 34 degrees c) had approximately twice the saturated fatty acid content of w/t organisms grown at approximately 22 degrees c. the gel-liquid crystal phase transitions o ...1977140245
lecithin requirement for the sporulation process in neurospora crassa.reversible inhibition of conidiogenesis occurred when lecithin was depleted from neurospora membranes by choline starvation.1977140164
analysis of repeated dna transcripts in neurospora crassa. 1976140149
thymine 7-hydroxylase from neurospora crassa. substrate specificity studies.a partially purified preparation of thymine 7-hydroxylase (thymine, 2-oxoglutarate : oxygen oxidoreductase (7-hydroxylating), ec from neurospora crassa was incubated with a number of pyrimidines chemically related to tyymine. 1. pyrimidines with oxygen or sulfur substituents on atoms nos. 2 and 4 as well as an alkyl group on atom nos. 1 or 5 were substrates. 2. km values were determined for 1-methyluracil, 1-ethyluracil, thymine, 6-azathymine, 1-methylthymine, 1-ethylthymine, 5-formyl ...1977139930
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
the subunit structure of the arom multienzyme complex of neurospora crassa. a possible pentafunctional polypeptide chain.a new procedure for the purification of the arom multienzyme complex from neurospora crassa is presented. important factors are the inactivation of proteinases by phenylmethanesulphonyl fluoride and the use of cellulose phosphate as an affinity adsorbent. a homogeneous enzyme, with a specific shikimate dehydrogenase activity of 70 units/mg of protein, is obtained in 25% yield. polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate, combined with cross-linking studies using ...1977139889
genetic and metabolic regulation of purine base transport in neurospora crassa.neurospora crassa can utilize various purine bases such as xanthine or uric acid and their catabolic products as a nitrogen source. the early purine catabolic enzymes in this organism are regulated by induction and by ammonium repression. studies were undertaken to investigate purine base transport and its regulation in neurospora. the results of competition experiments with uric acid and xanthine transport strongly suggest that uric acid and xanthine share a common transport system. it was also ...2002139563
genetic and kinetic analysis of neurospora crassa mtr mutants.allelic complementation occurs at the mtr (methyltryptophan resistance) locus. kinetic properties of neutral amino acid transport are altered for mtr mutants.1977139402
the effect of various "magdala reds" in inducing paramorphic colony growth in neurospora crassa. 1977139210
energy-linked potassium uptake by mitochondria from wild-type and poky strains of neurospora crassa.mitochondria from neurospora crassa, like mammalian mitochondria, carry out rapid, energy-linked k+ uptake and h+ release in the presence of valinomycin. the maximal rate of k+ uptake was about 1.0 mumol/mg of mitochondrial protein per min and was seen at valinomycin concentrations in the range of 100 to 200 mug per mg of mitochondrial protein and at k+ concentrations of 4 mm or above. uptake could be supported either by substrate oxidation or by adenosine 5'-triphosphate (atp), and was inhibite ...1977138675
composition and photoinduced biosynthesis of the carotenoids of a protoplast-like neurospora crassa "slime" mutant.a spheroplast-like "slime" mutant of neurospora crassa (lacking a rigid cell wall) was found to synthesize an identical spectrum of carotenoids as wild type strains except for beta-carotene. furthermore strict photoregulation of the biosynthesis of these pigments as well as the characteristics of photoinduced carotenogenesis were also nearly identical in the mutant and in the wild type.1977138402
liberation of protoplasts from mycelium of neurospora crassa by means of enzymes obtained from autolyzed cultures of this fungus.spherical protoplast-like structures were released from neuropsora crassa mycelia under the influence of cell-wall-lytic enzymes obtained from autolyzed cultures of this fungus, in 50 mm borate-citrate-phosphate buffer, ph 5.5 with 0.5-0.8 m mannitol for appropriate osmotic pressure. the protoplasts retain their morphological aspect for several days at 4 c, or for a longer time when they are washed by centrifugation and incubated with 0.8 m mannitol. the free protoplasts are sensitive to osmotic ...1976138385
lack of mutagenicity of vinyl chloride in two strains of neurospora detectable induction of mutations could be found in two strains of neurospora crassa after their conidia were treated with vinyl chloride, in ethanol solution and in its gaseous form. the results suggest that although n. crassa seems to lativating systems does not increase mutagenic activity of vinyl chloride in the two strains tested. at the same time these strains were mutated easily by uv and methyl methanesulfonate.1977138087
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
randomness tests on the sequence of ascal segregation classes in neurospora crassa.various statistical tests for randomness were made on the order of ascal classes in groups of asci from wild-type x asco crosses. there was no significant nonrandom clustering of asci of the same segregation class, nor a regular twinning of similar asci. any apparent observed clustering of similar ascal classes is probably an artefact or due to chance. 2 x n x2 tests showed that frequencies of individual ascus classes from different perithecia were generally homogeneous, as were second division ...2002137884
control of the production and partial characterization of repressible extracellular 5'-nucleotidase and alkaline phosphatase in neurospora crass.a new species of orthophosphate repressible extracellular 5'-nucleotidase (5'-ribonucleotide phosphohydrolase, ec was found to be released into mycelial culture media when a wild type strain of neurospora crassa was grown on limiting amounts of phosphate. the production of 5'-nucleotidase and extracellular acid and alkaline phosphatase was inhibited by the addition of rifampicin when it was added at the later stage of mycelial growth, but not when it was added at a very early stage. the ...1977137748
one-carbon metabolism in neurospora crassa wild-type and in mutants partially deficient in serine hydroxymethyltransferase.1. the concentrations of folate-dependent enzymes in neurospora crassa lindegren a wild type (fgsc no. 853), ser-l mutant, strain h605a (fgsc no. 118), and for mutant, strain c-24 (fgsc no. 9), were compared during exponential growth on defined minimal media. both mutants were partially lacking in serine hydroxymethyltransferase, but contained higher concentrations of 10-formyltetrahydrofolate synthetase than did the wild type. mycelia of the mutants contained higher concentrations of these enzy ...1976137722
re-investigation of the effects of l-glutamine and l-asparagine on the neurospora crassa nadp-specific glutamate dehydrogenase.l-glutamine, when purified free of traces of nh4+ present in solution, does not act as an alternative substrate to nh4+ for the nadp-specific glutamate dehydrogenase of neurospora. l-glutamine interferes with detection of small quantities of nh4+ by nessler's reagent. l-asparagine is not an alternative substrate to nh4+ for this enzyme.2002137720
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
episome-like behaviour of donor dna in transformed strains of neurospora crassa. 1976137361
new class of ribonucleic acid in neurospora associated with the outer cell envelope.extrinsic ribonucleic acid (rna) can be isolated from a kcl extract of neurospora crassa conidial cell surface products. it is heterogeneous in size. the bulk of this rna travels as a broad band, trailing the 5.8s ribosomal marker rna on electrophoretic gels. the extrinsic rna, when denatured, exhibites several discrete lengths between 50,000 and 130,000 daltons. melting profiles confirm the heterogeneity of the rna and indicate that 58% of the bases are involved in hydrogen bonding. analyses of ...1977137232
characterization of qa-2 mutants of neurospora crassa by genetic, enzymatic, and immunological techniques.genetic and complementation mapping studies using 20 qa-2 mutants defective for catabolic dehydroquinase indicate that the qa-2 gene encodes a single polypeptide chain and is the structural gene for catabolic dehydroquinase, a 220,000-molecular-weight protein composed of identical 10,000-molecular-weight subunits. many qa-2 mutants are capable of reversion, but no evidence has yet been obtained for nonsense mutations in this gene. the biochemical consequences of the mutations in two complementin ...1977137228
regulation of phosphate metabolism in neurospora crassa: identification of the structural gene for repressible acid phosphatase.a mutant of neurospora crassa with an altered repressible acid phosphatase has been isolated. the enzyme is much more thermolabile than that of wild type, and has an increased michaelis constant. tests of allelic interactions (in partial diploids) and in vitro mixing experiments were consistent with the mutation being in the structural gene for the enzyme. this gene, pho-3, was found to be located in the right arm of linkage group iv (lgiv). thus, pho-3 and the structural gene for repressible al ...2002137163
regulation of phosphate metabolism in neurospora crassa: identification of the structural gene for repressible alkaline phosphatase.five additional mutants of neurospora crassa have been isolated that lack the repressible alkaline phosphatase. the mutations in these strains map at a previously assigned locus on linkage group v designated pho-2 (gleason and metzenberg 1974). the five new mutants, as well as three previously isolated by gleason and metzenberg (1974), were examined for the presence of cross-reacting material to antibody prepared against purified wild-type enzyme. two of the mutants produced high levels of cross ...1976137162
superoxide dismutases in mitochondria from helianthls tuberosus and neurospora crassa. 1976137151
a second form of the single-strand specific endonuclease of neurospora crassa which is associated with a double-strand exonuclease.a second form of single-strand specific endonuclease, which is stable to heating up to 74 degrees c and does not bind strongly to phosphocellulose, has been partially purified from extracts of mycelia of wild-type neurospora crassa. the endonuclease is associated with an equally heat-stable exonuclease which degrades linear but not circular double-stranded dna and does not attack double-stranded rna. the exonuclease probably also degrades single-stranded dna. both endonuclease and exonuclease ac ...1976137069
lipid composition of neurospora crassa.the lipids of neurospora crassa, isolated in pure form from freeze-dried mycelium, were found to contain squalene, sterol esters, triglycerides, free fatty acids, geranylgeraniol, free sterols, carotenoids, cardiolipin, phosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl serine, and phosphatidic acid. the above compounds were isolated in pure form by column and thin layer chromatography and were characterized by infrared spectroscopy and chromatographic mobilities. fatty acid moieties ...1976136584
some required events in conidial germination of neurospora crassa. 2002136375
on the metabolic role of thymidine 2'-hydroxylase (thymidine, 2-oxoglutarate: oxygen oxidoreductase, ec in neurospora crassa. 2002136368
crystalline inducible kynureninase of neurospora crassa. 1976136367
nuclear suppressors of the [poky] cytoplasmic mutant in neurospora crassa. i. genetics and respiratory properties.six nuclear suppressors of the (poky) cytoplasmic mutant (sup-1, sup-3, sup-4, sup-5, sup-10, sup-14) have been obtained in neurospora crassa. the sup genes suppress the slow growth phenotype of (poky), and alleviate, at least partially, the deficiency of cyanide sensitive respiratory activity in the mycelium of this cytoplasmic mutant. the six suppressors are nonallelic, suppress the phenotypic effects of (stp-bl) in addition to (poky), but have no effect on the phenotype expression of the (mi- ...1976136291
a reduced pyridine nucleotides-diaphorase activity associated to the assimilatory nitrite reductase complex from neurospora crassa.the neurospora crassa assimilatory nad(p)h-nitrite reductase complex has associated a nad(p)h-diaphorase activity. 1. this nad(p)h-diaphorase activity can use either mammalian cytochrome c, 2,6--dichlorophenol-indophenol, ferricyanide, or menadione as electron acceptor from the reduced pyridine nucleotides, and requires flavin adenine dinucleotide for maximal activity. 2. it is inhibited by p-hydroxymercuribenzoate, 1 mum, and it is unaffected by cyanide, sulfite, or arsenite at concentrations w ...2002136235
regulation of hypoxanthine transport in neurospora crassa.hypoxanthine uptake and hypoxanthine phosphoribosyltransferase activity (ec were determined in germinated conidia from the adenine auxotrophic strains ad-1 and ad-8 and the double mutant strain ad-1 ad-8. the mutant strain ad-1 appears to lack aminoimidazolecarboximide ribonucleotide formyltransferase (ec or inosine 5'monophosphate cyclohydrolase (ec activities, or both, whereas the ad-8 strain lacks adenylosuccinate synthase activity (ec normal (or wild-typ ...1976135758
light-induced absorbance changes in cell-free extracts of neurospora crassa. 2002135267
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
reproducibility of vitamin assays with mutants of neurospora crassa maintained by freeze-drying.three mutant strains (atcc 9277, atcc 9278, atcc 9683) of neurospora crassa requiring choline, inositol, and p-aminobenzoic acid respectively for normal growth were deposited at the atcc by g.w. beadle 30 years ago and were preserved at various time intervals by freeze-drying. each preservation batch yielded cultures that, when used for biological assays, exhibited the same biochemical properties as they originally possessed. the freeze-drying technique is shown to be applicable to preserving bi ...2002134828
regulation of mitochondrial biogenesis in neurospora crassa. 1975134474
[a simple method for extraction of l-saccharopine from neurospora crassa]. 2002134378
gene order in the qa gene cluster of neurospora crassa.four different types of crosses have been used to establish the order of the four genes in the qa gene cluster of neurospora crassa, which encode the following proteins involved in the inducible catabolism of quinic acid: a regulatory (activator) protein (qa-1), catabolic dehydroquinase (qa-2), quinate dehydrogenase (qa-3), and dehydroshikimate dehydrase (qa-4). the four crosses involved (1) the ordering of the four qa genes relative to the closely-linked me-7 locus; (2) the ordering of the thre ...2002134253
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
permeability measurements on mitochondria from wild-type and poky strains of neurospora crassa.the permeability properties of isolated neurospora mitochondria were determined by measuring the rate at which the mitochondria swell in isotonic solutions of various organic and inorganic molecules. like mammalian mitochondria, wild-type neurospora mitochondria were impermeable to sucrose and only slightly more permeable to most inorganic ions (k, na, cl). their permeability to k was greatly increased by valinomycin and by monensin. in addition, the mitochondria contain specific systems mediati ...1976134027
depression of uracil uptake by ammonium in neurospora crassa.the mechanism of uracil uptake and one aspect of its regulation were studied in germinated conidia of neurospora crassa. uracil was found to be taken up by a transport mechanism that did not exhibit michaelis-menten kinetics. rather, the kinetic patterns indicated two separate systems or a single transport mechanism with negative cooperativity. cytosine and thymine inhibited uracil uptake, but uridine did not. the mutant strain uc-5-pyr-1, which failed to transport uracil, was used in reversion ...1976134026
neurospora crassa cytoplasmic ribosomes; ribosomal ribonucleic acid synthesis in the wild type.the biosynthesis of ribosomal ribonucleic acid (rrna) in wild-type neurospora crassa growing at 25 degrees c was investigated by continuous-labeling and pulsechase experiments using [5-3h]uridine. the results of these experiments suggest the following precursor-product relationships: the first rna molecule to be synthesized in significant quantities is the 2.4 x 10(6)-dalton (2.4-mdal) ribosomal precursor rna. this rna is cleaved to produce two species of rna with weights of 0.7 and 1.4-mdal. th ...1976134025
fine cytochemical detection of acid mucopolysaccharides in growing hyphae of neurospora crassa.the presence of mucopolysaccharides (mp) in neurospora crassa hyphae was detected in samples of cultures from 4 h to 5 days. using a modification of the method of rothman (1969), acid mp were identified by electron microscopy in vesicles located at the apex, septae, and throughout the cytoplasm of the hyphae. the size, number, and localization of these vesicles was related to the stage of growth of the fungus. the mechanisms of release and transport of these macromolecules are compared to the pr ...1976134010
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
mutation induction by difunctional alkylating agents in neurospora crassa.the genetic characterization of ad-3 mutants of neurospora crassa induced by two carcinogenic difunctional akylating agents, 1,2,4,5-diepoxypentane (dep) and 1,2,7,8-diepoxyoctane (deo), has shown that point mutations at the ad-3b locus have similar complementation patterns. in addition to the induction of point mutations, dep induces a low frequency (7.5%) of multilocus deletions, whereas deo induces an extremely high frequency (42.0%). the distribution of the different classes of ad-3 mutants ...2002133852
inhibition of neurospora crassa and yeast mitochondrial protein synthesis by ricin, a toxic protein inactive on e. coli protein synthesis. 1976133821
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 specific protease inhibitors from neurospora crassa.four natural protease inhibitors have been partially purified by heat treatment, ion-exchange chromatography pand gel filtration from neurospora crassa. the inhibitory activity has been estimated by measuring the inhibition of proteolysis of casein as well as by the protection of neurospora tryptophan synthase from proteolytic inactivation. the inhibitors are all oligopeptides and possess molecular weights in the range 5000-24 000 and appear to be very specific to neurospora proteases. they may ...1976133753
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
mutations in neurospora crassa which affect multiple amino acid transport systems.characterization of a double mutant, his-6: hgu-4, which is unable to utilize l-histidyl-glycine as a source of histidine has revealed a new locus on linkage group v. the hgu-4 genotype results in a generalized reduced transport activity for amino acids, with a concomitant increased resistance to amino acid analogs. transport rates and analog resistance for amino acids by this mutant are compared to the previously reported transport deficient mutants fpr-1, nap and un-3. transport of l-aspartate ...1976133719
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
changes of some enzymatic activities in iodoacetate-treated microconidiating cultures of neurospora iodoacetate-treated microconidating cultures of neurospora crassa, mycelial yield, sucrose consumption and ethanol production are reduced. the specific activity of glyceraldehyde-3-phosphate dehydrogenase is sharply decreased while the specific activities of glucose-6-phosphate dehydrogenase and of 6-phosphogluconate dehydrogenase are stimulated. a polyphenoloxidase is induced in the microconidiating cultures.1976133649
comparison of ultraviolet and blacklight for the induction of nutritional independence at two loci in neurospora crassa.the inactivating effects of both near ultraviolet (blacklight) and shortwave ultraviolet (uv) have been investigated for two auxotrophic strains of neurospora crassa. the two strain were indistinguishable with respect to their sensitivity to inactivation by blacklight, but differed in their sensitivity to uv (def congruent to 1.3-1.6 at 0.1 survival). the strains each carried an allele of different genes previously demonstrated as being capable of mutation in response to uv. the results confirm ...1976133288
ageing of neurospora crassa. iii. induction of cellular death and clonal senescence of an inositol-less mutant by inositol starvation and the protective effect of dietary antioxidants.clonal growth rate and cellular viability of an inositol-less mutant of neurospora crassa decline rapidly during deprivation of dietary inositol. dietary antioxidants, either nordihydroguaiaretic acid, vitamin e or 3,5-ditert.-butyl-4-hydroxybenzyl alcohol, protected cells and clones of the mutant from death and senescence. membrane deterioration with associated lipid autoxidation and consequent deleterious free radical reactions appear to be, in part at least, the causes of the mutant's death a ...2013133275
carnitine biosynthesis in neurospora crassa: enzymatic conversion of lysine to epsilon-n-trimethyllysine.the enzymatic conversion of l-lysine, epsilon-n-trimethyl-l-lysine the first series of reactions in the biosynthesis of carnitine in neurospora crassa, proceeds via sequential methylation of free l-lysine, epsilon-n-methyl-l-lysine, and epsilon -n-dimethyl-l-lysine. the latter two compounds have been shown to be intermediates in the biosynthesis of carnitine by radioisotope dilution and incorporation experiments in growing cultures of n. crassa 33933 (lys-) and 38706 (met-). methionine but not c ...1976133101
biochemical studies on the nit mutants of neurospora allele at each of the five nit loci in neurospora crassa together with the wild type strain have been compared on various nitrogen sources with regard to (i) their growth characteristics (ii) the level of nitrate reductase and its associated activities (reduced benzyl viologen nitrate reductase and cytochrome c reductase) (iii) the level of nitrate reductase and (iv) their ability to take up nitrite from the surrounding medium. results are consistent with the hypothesis that nit-3 is the str ...1976132603
ageing of neurospora crassa. ii. organic hydroperoxide toxicity and the protective role of antioxidant and the antioxygenic enzymes.cumene hydroperoxide and tert-butyl hydroperoxide at sublethal concentrations initially prevent growth of mycelia of wild-type neurospora crassa, but after a time the cells grow at a subnormal steady-state rate. the antioxidant nordihydroguaiaretic acid protects unadapted cells from hydroperoxide inhibition, leading to a decrease in the time before growth begins, an increase in steady-state growth rate and an increase in biomass production. the results of growth transfer experiments and enzyme m ...2006132584
ageing of neurospora crassa. i. evidence for the free radical theory of ageing from studies of a natural-death mutant.a recessive mutant of neurospora crassa, called natural-death, is characterized by a decreasing clonal growth potential under all nutritional conditions and the irreversible cessation of growth. the primary molecular defect of this mutant is not known. evidence presented here, based upon measurements of the activities and thermolabilities of several enzymes, suggests that faulty protein synthesis is probably not a cause of the senescence and death of the mutant, as suggested by lewis and hollida ...2008132583
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
compartmental behavior of ornithine in neurospora neurospora cells grown on minimal medium, most of the large ornithine pool is found in osmotically sensitive organelles, the "vesicles." in this paper kinetic studies on the compartmental behavior of ornithine and its derivatives are reported. analysis of the metabolism of a 10(-7) m pulse of uniformly labeled l-[14c] ornithine supports the following conclusions: (a) over 98% of the cellular ornithine is in the vesicles. (b) the amount of ornithine normally in the cytosol is about 0.3% of the ...1976132443
isolation and identification of the conidial germination factor of neurospora crassa.the germination-essential substance (germination factor [gf]) that is lost from conidia of neurospora crassa on exposure to solutions of low water activity has been isolated and identified as a group of iron-transport compounds, or siderochromes. the principal siderochrome of conidia is ferricrocin, a cyclic hexapeptide. a closely related substance, ferrichrome c, is tentatively identified as a minor constituent. the same substances are also present in extracts of mycelium along with small amoun ...1976132426
specificity of five intracellular proteinases of neurospora crassa. 1976132374
physical map of circular mitochondrial dna from neurospora crassa. 1975132366
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
the neurospora plasma membrane atpase is an electrogenic pump.biochemicalical evidence is presented which demonstrates that the neurospora crassa plasma membrane atpase (atp phosphohydrolase, ec is an electrogenic pump. the electrical potential across the neurospora plasma membrane, as monitored by [14c]scn- uptake by isolated neurospora plasma membrane vesicles, is markedly increased interior positive under conditions of atp hydrolysis catalyzed by plasma membrane atpase. [14c]scn- uptake by the vesicles is minimal in the presence of tris phospha ...1976131943
selection of extranuclear mutants of neurospora crassa.a procedure is described that produce primarily extranuclear mutants, of neurospora carassa. an analysis of five mutants. [cni-3], [rsp-2], [rsp-3], e1rsp-4], is presented. all five mutants segregate in an extranuclear manner. they can be assorted into two classes based on their respiratory properties: (1) those with cyanide-insensitive respiration (cni); (2) those with slow respiration (rsp). all of the mutants are female sterile. the respiratory trait can be placed in different nuclear backgro ...1976131734
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