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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
[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
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
superoxide dismutases in mitochondria from helianthls tuberosus and neurospora crassa. 1976137151
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
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
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
biphasic interactions between a neurospora crassa glutamate dehydrogenase and reduced nicotinamide-adenine dinucleotide phosphate. 197612047
electron spin resonance investigations of mitochondrial electron transport in neurospora crassa. characterization of paramagnetic intermediates in a standard strain.1. submitochondrial particles from neurospora strain inl-89601 have been analyzed by electron spin resonance spectroscopy (esr). numerous signals due to iron-sulfur proteins are observed at low temperatures. analysis of these esr signals at various temperatures allows the assignment of resonances to iron-sulfur centers 1-5 that have been described in other organisms. there are no discrepancies between the signals seen in neurospora and those described in other organisms and it is likely that neu ...197612965
glutamine utilization in both the arginine-specific and pyrimidine-specific carbamoyl phosphate synthase enzymes of eurospora crassa.as glutamine-dependent carbamoyl phasphate synthetase (cps) activity in some organisms is composed of a glutaminase and an ammonium-dependent cps, cps- mutants in neurospora crassa were examined for glutamine- and ammonium-dependent cps activities. no evidence was found that the genetic location of these two functions were separable. this is discussed with reference to the close genetic proximity of the cpspyr and aspartate carbamoyltransferase (act) structural gene (pyr-3) and the arg-2 gene wh ...1976189179
induction of enzymes of the glycerophosphate pathway in leu-5 mutants of neurospora crassa.the inducible cytosolic glycerokinase and mitochondrial glycerol-3-phosphate dehydrogenase have been examined during the glycerol-specific induction in neurospora crassa. although both the fully induced levels and the respective rates of synthesis of these two enzymes were less than observed with wild-type cells, there were no major differences in the relative rates of induction of the glycerol-3-phosphate dehydrogenase at either permissive or restrictive temperatures. these results indicate tha ...1976189751
episome-like behaviour of donor dna in transformed strains of neurospora crassa. 1976137361
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
analysis of repeated dna transcripts in neurospora crassa. 1976140149
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
regulation of hypoxanthine transport in neurospora crassa.hypoxanthine uptake and hypoxanthine phosphoribosyltransferase activity (ec 2.4.2.8) 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 2.1.2.3) or inosine 5'monophosphate cyclohydrolase (ec 3.5.1.10) activities, or both, whereas the ad-8 strain lacks adenylosuccinate synthase activity (ec 6.3.4.4). normal (or wild-typ ...1976135758
effects of chloramphenicol on the circadian rhythm of neurospora crassa.chloramphenicol, an inhibitor of mitochondrial protein synthesis, shortened the period length of the circadian rhythm in the timex strain of neurospora crassa by 2 hours. both the l(+) threo and d(-) threo optical isomers had the same effect on the period of the rhythm, whereas only the d(-) threo isomer significantly inhibited mitochondrial protein synthesis. tetracycline, another inhibitor of mitochondrial protein synthesis, did not change the period of the circadian rhythm. the effect of chlo ...197616659724
the effect of cyclic adenosine monophosphate on the growth of neurospora crassa. 1976185527
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
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
mutational amino acid replacements in neurospora crassa nadp-specific glutamate dehydrogenase. 19769517
the function of mitochondrial genes in neurospora crassa.the 18 extranuclear mutants of neurospora crassa, without exception, have abnormal mitochondrial respiratory systems. on the basis of genetic, phenotypic and physiological criteria, these mutants are divided into four groups: 1) the cytochrome aa3 and b deficient "poky" variants that are defective in mitochondrial ribosomes assembly, 2) the cytochrome aa3 deficient mutants, [mi-3] and [exn-5], that appear to have genetic lesions affecting a component of a regulatory system controlling cytochrome ...1976187290
adenosine 3':5'-cyclic monophosphate deficiency in neurospora crassa.depending on growth conditions, the adenosine 3':5'-cyclic monophosphate (cyclic amp) levels of the fr mutant, a morphologically aberrant strain of neurospora crassa, are reduced 2- to 5-fold. by taking advantage of the differences in phenotype of fr in liquid and agar cultures and the positive response of fr grown on solid support to exogenous theophylline, a relationship between the degree of morphological abnormality and intracellular cyclic amp levels of the mutant is observed. progressive r ...1976184453
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
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
neurospora crassa glutamine synthetase. purification by affinity chromatography and characterization of subunit structure.neurospora crassa glutamine synthetase was purified to homogeneity by a procedure based on affinity chromatography. the enzyme is adsorbed to a matrix of anthranilic acid bound to sepharose and eluted with amp. different experimental approaches indicate that the enzyme has an octameric structure formed by subunits of identical molecular weight.19767567
the location of the feedback-specific region with the pyrimidine-3 locus of neurospora crassa.the purimidine-3 locus of neurospora crassa specifies two enzyme activities, pyrimidine-specific carbamyl phosphate synthetase (cpspyr) and aspartate transcarbamylase (atc). atc is translationally distal. cpspyr, but not atc, is subject to feedback inhibition by uridine triphosphate (utp). to investigate the location of the feedback-specific region within the locus, inhibition of a number of pyr-3 alleles by utp was investigated. all cps+ atc- polar alleles, revertants of cps- atc- polar alleles ...1976187923
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
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
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
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
compartmental behavior of ornithine in neurospora crassa.in 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
changes of some enzymatic activities in iodoacetate-treated microconidiating cultures of neurospora crassa.in 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
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
heteromorphism for heterokaryon incompatibility genes in natural populations of neurospora crassa.five neurospora crassa isolates from each of three sites in louisiana were compared for genotype at five heterokaryon incompatibility (het) loci. the comparisons were made using duplications (partial diploids), based on the fact that duplications heterozygous for het loci have strikingly abnormal phenotypes which greatly facilitate the study of such genes. duplications were synthesized in crosses between the wild strains (normal chromosome sequence) and testers of defined het genotype and having ...197617248714
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
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 crassa.one 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
role of mannosyl lipid intermediate in the synthesis of neurospora crassa glycoproteins.particulate membrane preparations from neurospora crassa incorporated mannose from gdp-[14c] mannose into endogenous lipid and particulate protein acceptors. synthesis of the mannosyl lipid is reversible in the presence of gdp. chemical and chromatographic characterization of the mannosyl lipid suggest that it is a mannosylphosphorylpolyisoprenol. the other endogenous acceptor was precipitated by trichloracetic acid. gel filtration and electrophoresis studies before and after treatment with prot ...19765115
control of the formation of extracellular ribonuclease in neurospora crassa.a finding was made that a species of ribonuclease is released into mycelial culture media when a wild-type strain of neurospora crassa was grown on limiting amounts of phosphate. the ribonuclease activity in the fully derepressed state extends to about 60 to 100 fold of that in the repressed state. the synthesis of the ribonuclease was inhibited by the addition of rifampicin, cycloheximide or orthophosphate. three molecular species of the ribonuclease were found. two enzyme fractions showing lar ...19765154
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 3.6.1.3) 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
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
biochemical and genetic studies on galactosamine metabolism in neurospora crassa.in 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
modification of the regulatory properties of pyruvate kinase of neurospora by growth at elevated temperatures.pyruvate kinase (ec 2.7.1.40) was isolated from neurospora crassa mycelium grown at 28 degrees c (pk-28) and at 42 degrees c (pk-42). the regulatory properties, particularly the response towards the allosteric effector fructose 1,6-diphosphate (fdp), was different in the two enzymes. pk-28 showed an activation by fdp but pk-42, under comparable conditions, appeared to be activated by low concentrations of fdp and inhibited by higher ones. for pk-28, complex formation with fdp results in a loweri ...19766132
"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
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
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
action spectrum between 260 and 800 nanometers for the photoinduction of carotenoid biosynthesis in neurospora crassa.an action spectrum for light-induced carotenoid biosynthesis in neurospora crassa was determined in 4 to 20 nm steps from 260 to 800 nm. four-day, dark-grown mycelial pads of n. crassa were exposed to varying amounts of monochromatic radiant energy and time. after a 48-hour incubation period at 6 c, carotenoid content was assayed spectrophotometrically in vivo. the action spectrum has maxima at 450 and 481 nm in the visible range and at 280 and 370 nm in the ultraviolet. a pigment synthesized by ...197616659499
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
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
introduction of interrupted secondary structure in supercoiled dna as a function of superhelix density: consideration of hairpin structures in superhelical dna.pm2 dna was prepared with different superhelical densities (sigma) in order to examine the relationship betweenn supercoiling and the occurrence of a region(s) of unpaired bases in this dna. a previous study showed that ch3hgoh reacts with native superhelical pm2 dna more rapidly than the nicked form ii. this evaluation of binding, monitored through the change of sedimentation velocity, was repeated on pm2 dna i with different superhelical densities. early binding is detected by an increase in s ...19761255870
characterization of a seventh different subunit of beef heart cytochrome c oxidase. similarities between the beef heart enzyme and that from other species.beef heart cytochrome c oxidase has been resolved into seven subunits by electrophoresis in highly cross-linked gels containing urea and sodium dodecyl sulfate. the molecular weights of the polypeptides are estimated to be i, 35 400; ii, 24 100; iii, 21 000; iv, 16 800; v, 12 400; vi, 8200; and vii, 4400. it has been shown that subunits ii and iii can coelectrophorese on standard sodium dodecyl sulfate-polyacrylamide gels and appear as a single component with an apparent molecular weight of 22 5 ...1976181053
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
enzymatic determination of nonrandom incorporation of 5-bromodeoxyuridine in rat dna.secondary cultures of normal rat embryo cells were synchronized by a double thymidine block and pulsed with 10(-7) m 5-[3h]bromodeoxyuridine (brdurd) or 10(-7) m[3h]thymidine during an entire s phase (7.5 h). to examine the pattern of [3h]thymidine, dna was immediately extracted and purified at the completion of the s phase, cscl density gradient centrifugation revealed that substitution for thymine by bromouracil was less than 7%. single-strand specific nucleases obtained from aspergillus oryza ...1976133713
the 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
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
inhibition of neurospora crassa and yeast mitochondrial protein synthesis by ricin, a toxic protein inactive on e. coli protein synthesis. 1976133821
action of intracellular proteinases on mitochondrial translation products of neurospora crassa schizosaccharomyces pombe.gel electrophoretic analysis of mitochondrial membranes from neurospora crassa shows the presence of a polypeptide fraction with apparent molecular weights of 7000 - 1200, which is synthesized on mitochondrial ribosomes. this fraction comprises between 10 and 50% of total mitochondrial translation products. evidence is presented that the major part of this fraction is derived from components with higher apparent molecular weights by proteolytic activity. the proteolytic activity is located in ve ...1976133982
wall structure of the neurospora hyphal apex: immunofluorescent localization of wall surface antigens.antisera have been raised in rabbits against three wall fractions from neurospora crassa. fractions were separated according to mahadevan & tatum (1965), i.e. fraction i, glucan-peptide-galactosamine complex; fraction iii, laminarin-like glucan; and fraction iv, chitin. distinct patterns of immunofluorescent staining were obtained using an indirect staining method. hyphae stained with antiserum to fraction i showed maximum fluorescence in the apical and/or subapical regions: in both cases, fluor ...1976134131
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
crystalline inducible kynureninase of neurospora crassa. 1976136367
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
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
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
identification of a functional arginine residue involved in coenzyme binding by the nadp-specific glutamate dehydrogenase of neurospora.the nadp-specific glutamate dehydrogenase (ec 1.4.1.4) of neurospora crassa is inhibited by reaction with 1,2-cyclohexanedione which binds to arginine residues. with the 14c-labeled reagent, a peptide was isolated with the sequence: gly-gly-leu-arg-leu-his-pro-ser-val-asn-leu, corresponding to residues 78 through 88 in the protein. the arginine, residue 81, was present as n7,n8-(1,2-dihydroxycyclohex-1,2-ylene)-arginyl (or dhch-arginine). present evidence indicates that this arginine residue res ...19769404
lytic enzymes in the autolysis of filamentous fungi.the degrees of autolysis attained by five different genera of filamentous fungi during an incubation period of 60 days, under the same culture conditions were: 87.3% for penicillium oxalicum; 65.9% for neurospora crassa; 62.7% for polystictus versicolor; 51.7% for aspergillus niger and 23.5% for nectria galligena. n. crassa, a. niger and p. versicolor reached the end of the autolysis during this incubation period (60 days), whereas p. oxalicum and n. galligena did not. the excretion of the lytic ...197613304
formation of nadph-nitrate reductase activity in vitro from aspergillus nidulans niad and cnx mutants.mutants of a. nidulans at several loci lack detectable nadph-nitrate reductase activity. these loci include niad, the structural gene for the nitrate reductase polypeptide, and five other loci termed cnxabc, e, f, g and h which are presumed to be involved in the formation of a molybdenum-containing component (mcc) necessary for nitrate reductase activity. when forzen mycelia from a. nidulans deletion mutant niad26 were homogenized in a ten broeck homogenizer together with frozen mycelia from eit ...1976796678
[a flavinogenic mutant of the yeast pichia guilliermondii with impaired iron transport].a mutant of the yeast pichia guilliermondii was produced by means of uv; the mutant was capable of riboflavin overproduction in the presence of high concentrations of iron in the medium. the content of total and non-hemin iron and cytochrome c, and the activity of catalase, were lower in the cells of the mutant than in the parent cells, while the activity of riboflavin synthetase was higher. the content of iron in the cells increased when the mutant was cultivated on media with citric acid, side ...1976933879
site of cleavage of superhelical phix174 replicative form dna by the single strand-specific neurospora crassa endonuclease.experiments with the neurospora crassa single strand-specific endonuclease have provided evidence for the existence of regions of partially single-stranded character in covalently closed superhelical replicative form dna of phix174. the nuclease converts the superhelical molecules to either singly hit relaxed circular or doubly hit linear molecules. we show that the initial cleavage of phix174 superhelical dna is a "nick" bounded by a 5'-phosphate and a 3'-hydroxyl; no nucleotides are excised as ...1976942717
in situ effects of s1 endonuclease (neurospora crassa) on pachytene chromatin of xenopus laevis females at metamorphosis. 1977837986
determination of the absolute configuration at c-20 and c-24 of ergosterol in ascomycetes and basidiomycetes by proton magnetic resonance spectroscopy.samples of ergosterol isolated from saccharomyces cerevisiae, neurospora crassa, and agaricus sp., and commercial ergosterol all displayed identical proton magnetic resonance (pmr) spectra at 220 mhz. from the effects produced on the doublet for c-21 by epimerization at c-20 and c-24 in sterols of known configuration, the absolute configurations at these positions in ergosterol were determined. the data demonstrate that ergosterol from both ascomycetes and basidiomycetes is the same and that at ...1977853879
differential excision from dna of the c-8 and n2 guanosine adducts of n-acetyl-2-aminofluorene by single strand-specific endonucleases.purified duck reticulocyte dna was reacted in vitro with [9-14c]-n-acetoxy-n-acetyl-2-aminofluorene. hydrolysis of the [14c]-n-acetyl-2-aminofluorene-modified dna followed by sephadex lh-20 column chromatography showed that 85% of the dna-bound [14c]-n-acetyl-2-aminofluorene was n-(deoxyguanosin-8-yl)-n-acetyl-2-aminofluorene and 15% was 3-(deoxyguanosin-n2-yl)-n-acetyl-2-aminofluorene. when this modified dna was incubated with the single strand-specific nuclease, s1, and the undigested fraction ...1977908018
neurospora crassa glutamine synthetase. translation of specific messenger ribonucleic acid in a cell-free system derived from rabbit reticulocytes.the total reticulocyte lysate cell-free protein-synthesizing system was incubated in the presence of neurospora crassa rna. with the aid of an antibody directed against purified n. crassa glutamine synthetase, the synthesis of a specific protein was detected. this protein precipitates with antiglutamine synthetase using both direct and indirect procedures, migrates with the same molecular weight as the monomer of n. crassa glutamine synthetase when subjected to acrylamide gel electrophoresis in ...197716013
the stereospecificity of nitrate reductase for hydrogen removal from reduced pyridine nucleotides.the stereospecificity of the hydrogen removal from reduced pyridine nucleotides catalyzed by nitrate reductase (nadh : nitrate oxidoreductase, ec 1.6.6.1, and nad(p)h : nitrate oxidoreductase, ec 1.6.6.2) was investigated. a high degree of enzyme purification was required to obtain conclusive results. improvements are described for the purification of nitrate reductase from chlorella fusca and from spinach (spinacea oleracea, l.) leaves. the latter enzyme is shown to contain a cytochrome. with h ...197716653
isocitrate lyase from neurospora crassa: ph dependence of catalysis and interaction with substrates and inhibitors. 197718092
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. iv. the cooh-terminal 669 residues of the peptide chain; comparison with other glutamate dehydrogenases.a sequence is presented for the cooh-terminal 669 residues of the nad-specific glutamate dehydrogenase of neurospora crassa. comparison of this sequence with those of the vertebrate glutamate dehydrogenases of chicken and bovine liver and with the nadp-specific enzyme of neurospora shows some similarities in sequences around residues previously identified as important for the function of these enzymes. these are: (a) the reactive lysine residue of low pk in the nadp and the vertebrate enzymes; ( ...197721191
metabolism of mandelic acid by neurospora crassa.preliminary studies on the metabolism of manelic acid by neurospora crassa reveal the operation of a pathway for its degradation which involves benzoyl formic acid, benzaldehyde, benzoic acid, 4-hydroxybenzoic acid, and protocatechuic acid as the intermediates. this pathway is different from the followed by bacterial systems and is the same as that observed in aspergillus niger.197721739
mutation induction by the antischistosomal drug f30066 in various test systems.the genetic activity of furapromidium (f30066), an antischistosomal drug, was studied in salmonella typhimurium, saccharomyces cerevisiae, neurospora crassa and cultured chinese hamster cells. the results show that f30066 induces gene mutations in s. typhimurium, n. crassa and chinese hamster cells. this compound also causes gene conversions in s. cerevisiae.1977138086
a complete cleavage map of neurospora crassa mtdna obtained with endonucleases eco ri and bam hi.a physical map of neurospora crassa mitochondrial dna has been constructed using specific fragments obtained with restriction endonucleases. the dna has 5 cleavage sites for endonuclease bam hi, 12 for endonuclease eco ri and more than 30 for endonuclease hind iii. the sequence of the eco ri and bam hi fragments has been established by analysis of partial fragments. by digestion of the eco ri fragments with bam hi, a complete overlapping map has been constructed. the position of the largest hind ...1977139928
regulation of exocellular protease in neurospora crassa: induction and repression under conditions of nitrogen starvation. 1977143241
the ribosomal rna genes on neurospora crassa mitochondrial dna are adjacent.hybridization of separated 24 s and 17 s ribosomal rna from neurospora crassa mitochondrial ribosomes to restriction fragments of mitochondrial dna leads to the conclusion that the large and small ribosomal rna are adjacent on the restriction endonuclease cleavage map of the dna. the distance between the two genes is estimated at 900 basepairs. this result is consistent with the existence of a ribosomal precursor rna in n. crassa mitochondria and is in contrast to the situation in yeast, where t ...1977143295
expression in escherichia coli k-12 of the structural gene for catabolic dehydroquinase of neurospora crassa.the inducible quinic acid catabolic pathway of neurospora crassa is controlled by four genes, the qa cluster which includes structural genes qa-2, qa-3, qa-4 for three enzymes and a regulatory gene, qa-1. in this paper we report the molecular cloning of at least the qa-2 gene which encodes the catabolic dehydroquinase (5-dehydroquinate hydro-lyase, ec 4.2.1.10). endo.r.hindiii restriction endonuclease fragments of n. crassa dna from a qa-1(c) (constitutive) mutant and of escherichia coli plasmid ...1977143663
biosynthesis of carnitine in neurospora crassa.in growing cultures of neurospora crassa lysine auxotroph 33933, (a) beta-hydroxy-epsilon-n-trimethyllysine and gamma-n-trimethylaminobutyraldehyde, postulated precursors of carnitine in the rat, effectively blocked synthesis of labeles carnitine from epsilon-n-[ch3-3h]trimethyllysine; and (b) beta-hydroxy-epsilon-n[ch3-3h[trimethyllysine and gamma-n-[ch3-3h]trimethylaminobutyraldehyde were effectively utilized for carnitine formation. from these isotopic experiments, the latter steps of carniti ...1977144128
enzymatic release of iron from sideramines in fungi. nadh:sideramine oxidoreductase in neurospora crassa.young mycelia of the fungus neurospora crassa contain a soluble nadh-linked sideramine reductase, which may be responsible for liberating iron in vivo from accumulated sideramines during iron-deficient cultivation. the enzymes can be assayed using a soluble supernatant fraction, edta, and an atmosphere of pure nitrogen. the enzyme is stable without loss of activity up to 45 degrees c and has an optimum of activity at ph 7.0. besides coprogen (km = 100 micrometer, v=2.8 nmol/min per mg protein), ...1977144535
nucleotide sequence of neurospora crassa cytoplasmic initiator trna.initiator methionine trna from the cytoplasm of neurospora crassa has been purified and sequenced. the sequence is: pagcugcaum1ggcgcagcggaagcgcm22gcy*gggcucaut6aacccggagm7gu (or d) - cacucgaucgm1aaacgag*uugcagcuaccaoh. similar to initiator trnas from the cytoplasm of other eukaryotes, this trna also contains the sequence -aucg- instead of the usual -tphicg (or a)- found in loop iv of other trnas. the sequence of the n. crassa cytoplasmic initiator trna is quite different from that of the corresp ...1977146192
molybdenum cofactors from molybdoenzymes and in vitro reconstitution of nitrogenase and nitrate reductase.a molybdenum cofactor (mo-co) from xanthine oxidase (xanthine:oxygen oxidoreductase, ec 1.2.3.2) can be isolated from the enzyme by a technique that has been used to isolate an iron-molybdenum cofactor (femo-co) from component i of nitrogenase. n-methylformamide is used for the extraction of these molybdenum cofactors. mo-co from xanthine oxidase activates nitrate reductase (nadph:nitrate oxidoreductase, ec 1.6.6.2) in an extract from neurospora crassa mutant strain nit-1; however, femo-co is un ...1977146198
cytochrome c-specific protein methylase iii from neurospora crassa.a protein methylase iii responsible for specifically methylating the cytochrome c in neurospora crassa was partially characterized by using unmethylated horse heart cytochrome c as a substrate. this enzyme utilizes s-adenosyl-l-methionine as the methyl donor. an analysis of the distribution of [14c]methyl groups in the peptides obtained by chymotrypsin digestion of the enzymically methylated cytochrome c showed that all of the radioactivity could be recovered within a single peak after chromatog ...1977196592
[effect of liver chromatin dnase on closed circular dna of pm-2 phage and simian virus 40].comparative effect of the dnase from rat liver chromatin and neurospora crassa endonuclease s1 on closed circular superhelical dna of pm-2 phage and simian virus 40 is studied. it is shown that both of them--the dnase from chromatin proteins and endonuclease s1--are specific to single-stranded regions in dna molecular. it is suggested that chromatin protein dnase participates in reparation processes.1977196682
expression of the structural gene for catabolic dehydroquinase of neurospora crassa in escherichia coli k12. 1977157795
introduction. membrane transport of peptides.carrier-mediated membrane transport of small peptides is now realized to be a process of wide biological distribution, occurring not only in the small intestine and elsewhere in the animal body but also in bacteria, yeast, the mould neurospora crassa, and probably in higher plants during the germination of seeds. the important features of peptide transport are outlined, and possible relationships between peptide transport and hydrolysis are discussed. peptide transport is a stereochemically spec ...1977244390
studies on the transcription complex of escherichia coli rna polymerase.to study the chain elongation phase of enzymatic rna synthesis ternary transcription complexes with t7 dna or poly[da) - (dt)] as template were isolated by gel exclusion chromatography. the dna in these complexes contains single-stranded regions which are recognized by a single-strand-specific nuclease from neurospora crassa. the non-codogenic dna strand in the poly[(da) - (dt)] ternary complex is preferentially hydrolysed by the nuclease. the polymerase protects predominantly the codogenic stra ...1977336358
cyclic amp and the plasma membrane potential in neurospora crassa.diverse treatments, which have been shown by slayman, c. l. (1977) in water relations in membrane transport in plants and animals (jungreis, a., hodges, t. k., kleinzeller, a., and schultz, s. g., eds) pp. 69-86, academic press, new york, to depolarize the plasma membrane of neurospora, increase levels of adenosine 3':5'-monophosphate (cyclic amp) in the organism. the treatments include those producing large transport fluxes of metabolizable or nonmetabolizable compounds, rapid temperature drops ...1977198403
mitochondrial ribosome assembly in neurospora crassa. chloramphenicol inhibits the maturation of small ribosomal subunits. 1977146091
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