PMID(sorted descending)
cyclic amp levels in relation to membrane phospholipid variations in neurospora crassa.the correlation between membrane phospholipid composition and total cyclic amp levels was investigated by using neurospora lipid auxotrophs under various supplementation conditions. the lipid composition of the supplemented cultures was determined, and the intracellular and extracellular cyclic amp levels were measured at various stages of the culture growth. kinetic parameters and the thermostability of adenylate cyclase and of cyclic amp-dependent phosphodiesterase were measured under all supp ...19836307199
calmodulin-stimulated cyclic nucleotide phosphodiesterase from neurospora crassa.cyclic nucleotide phosphodiesterase has been partially purified by calmodulin-sepharose affinity chromatography from a soluble extract of neurospora crassa. the phosphodiesterase activity remained bound to the affinity column even in the presence of 6 m urea and could only be eluted by calcium chelation. the enzyme exhibits camp and cgmp phosphodiesterase activities. both activities can be enhanced by calmodulin in a ca2+-dependent manner. stimulation of cyclic nucleotide phosphodiesterase by ca ...19836305427
[effect of the cyclic nucleotide level on the degree of carotenoid pigment formation in the mycelial cells of neurospora crassa].the relation between the content of cyclic nucleotides and the rate of formation of carotenoid pigments in the neurospora crassa mycelium cells was investigated. light derepression of the carotenoid synthesis during the photoinduction lag-period induced a transient decrease of the camp content. the intracellular camp content was in negative correlation with the constitutive level of carotenoid pigments. the cgmp content remained unchanged during the photoinduction lag-period and showed no correl ...20136304680
calcium as a branching signal in neurospora crassa.the divalent cation ionophore a23187 was found to induce apical branching in neurospora crassa. optimal effects were obtained by treatment with 0.1 mm ionophore for 30 min. branching first became manifest during or shortly after treatment; successive rounds of branching could be observed at later times. calcium starvation of the mycelium markedly reduced its subsequent response to the ionophore, whereas starvation for other divalent cations had no detectable effect. the branching response was ma ...19836304014
mitochondrial variants of neurospora intermedia from nature.from a sample of 122 natural isolates of neurospora intermedia collected recently from around the world, five variants had erratic stop-start growth patterns reminiscent of the phenotype of "stopper" laboratory extranuclear mutants of neurospora crassa. like laboratory isolated mutants, the natural "stopper" variants were sterile as protoperithecial parents and transmitted the variant growth phenotypes very inefficiently, if at all, as male parents. heterokaryon tests could not be made because o ...19826303535
developmental regulation of nad+ kinase in neurospora crassa.the specific activity of nad+ kinase (atp:nad+ 2'-phosphotransferase, ec from neurospora crassa shows sharp peaks when the organism enters a new developmental stage of the asexual life cycle: the peaks are observed during hydration and germination of conidia, at the transition from exponential to stationary growth and at the photostimulated conidiation. as stimulation of nad+ kinase activity by light in conidiating mycelium is not sensitive to translation inhibitors, the activation of ...19826303242
construction of a shuttle vector for the filamentous fungus neurospora crassa.we have constructed a recombinant plasmid, pals-1, that replicates autonomously in both neurospora and escherichia coli. pals-1 consists of the mitochondrial plasmid from neurospora strain p405-labelle, the neurospora qa-2+ gene, and e. coli plasmid pbr325. pals-1 transforms the neurospora qa-2+ gene at frequencies 5- to 10-fold higher than those for plasmids that transform mainly by integration. when e. coli was transformed with dna from neurospora transformants, we recovered not only pals-1 bu ...19836302667
chimeric plasmid that replicates autonomously in both escherichia coli and neurospora crassa.a hybrid pbr322 plasmid (designated pdv1001) containing two functional escherichia coli antibiotic resistance genes (kanr and camr) and a qa-2+ gene from neurospora crassa transforms n. crassa qa-2- mutants to qa-2+ with a frequency of ca. 5 x 10(-5) per regenerated spheroplast (ca. 100 transformants per microgram of plasmid dna). this plasmid can replicate autonomously without integrating into the n. crassa genome. the autonomously replicating hybrid plasmid was detected in n. crassa transforma ...19836302666
release of high molecular weight dna from neurospora crassa using enzymic digestions.methods are described that allow extraction of high molecular weight dna from germinated conidia of neurospora crassa. by labelling dna with ribonucleosides, early conidia were shown to be active in dna synthesis. these cells when treated with the enzyme zymolyase became fragile and could be readily lysed with ionic detergents to release high molecular weight dna. the dna extracted from zymolyase treated cells on to alkaline sucrose gradients sedimented as a heterogeneous species of up to 150 x ...19836302203
structural variations and optional introns in the mitochondrial dnas of neurospora strains isolated from nature.mitochondrial dnas from ten wild-type neurospora crassa, neurospora intermedia, and neurospora sitophila strains collected from different geographical areas were screened for structural variations by restriction enzyme analysis. the different mtdnas show much greater structural diversity, both within and among species, than had been apparent from previous studies of mtdna from laboratory n. crassa strains. the mtdnas range in size from 60 to 73 kb, and both the smallest and largest mtdnas are fo ...19836300945
structural and functional evidence for multiple channel complexes in the outer membrane of neurospora crassa mitochondria.the outer membrane of mitochondria contains proteins that form channels called vdac (voltage-dependent anion-selective channels). two independent lines of evidence suggest that these channels occur in specific complexes in the outer membrane of neurospora mitochondria. electron microscopic images of these outer membranes reveal polymorphic crystalline arrays of putative pores. these arrays can be shown to be interrelated by movement in the membrane plane of a particular rigid channel triplet or ...19836300902
a family of repetitive palindromic sequences found in neurospora mitochondrial dna is also found in a mitochondrial plasmid dna.neurospora mtdna contains a repetitive, 18 nucleotide palindromic sequence (5'-ccctgcagtactgcaggg-3') that contains two closely spaced psti sites (ctgcag) in the arms of the palindrome (yin, s., heckman, j., and rajbhandary, u. l. (1981) cell 26, 325-332). in the present study, dna sequence analysis was carried out to determine whether psti palindromes are present in an apparently distinct genetic element, the 3.6-kilobase mitochondrial plasmid from neurospora crassa strain mauriceville-1c (fgsc ...19836300080
transfer of proteins into mitochondria. precursor to the adp/atp carrier binds to receptor sites on isolated mitochondria.the precursor form of neurospora crassa mitochondrial adp/atp carrier synthesized in a cell-free protein-synthesizing system can be imported into isolated mitochondria. if the mitochondrial transmembrane potential is abolished, import does not occur but the precursor binds to the mitochondrial surface. upon reestablishment of the membrane potential, the bound precursor is imported. this occurs without dissociation of the bound precursor from the mitochondrial surface. we conclude that the bindin ...19836300074
nitrogen source regulates glutamate dehydrogenase nadp synthesis in neurospora crassa.neurospora crassa glutamate dehydrogenase-nadp (ec has a higher activity when mycelium is grown on ammonium or nitrate as nitrogen source than when grown on glutamate or glutamine. quantitative immunoelectrophoresis established that, under all conditions, enzyme activity corresponded to enzyme concentration. isotope incorporation studies demonstrated that the nitrogen source exerts its regulation at the level of de novo enzyme synthesis.19836300039
intracellular localization of neurospora crassa endo-exonuclease and its putative precursor.endo-exonuclease of rapidly growing mycelia of neurospora crassa was found to be distributed in a ratio of about 1.6:1 in vacuoles and in mitochondria where it is associated with the inner membrane. although the activity in vacuoles was readily released by osmotic shock, very little of that in mitochondria was released by this method. the mitochondrial activity was partially (60 to 70%) released by sonication, and the remaining activity was solubilized in the presence of triton x-100. an inactiv ...19836300036
structure and organization of trna, rrna, and protein genes in neurospora crassa mitochondria.our studies on neurospora crassa mitochondria have included sequence analysis of trnas, mapping and cloning of the trna, rrna, and protein genes and the dna sequence analysis of these genes. results from trna sequence analyses explain how the mitochondrial protein synthesizing system can function with a much smaller number of trnas than other systems. mapping studies have shown that the two rrna genes and almost all of the trna genes are clustered onto a third of the mitochondrial genome. the tw ...19826300028
cloning of the am (glutamate dehydrogenase) gene of neurospora crassa through the use of a synthetic dna a previous study the alteration in the amino acid sequence of neurospora crassa nadp-specific glutamate dehydrogenase (gdh) resulting from two mutually compensating frameshift mutations was used to deduce the first 17 nucleotides of the coding sequence of the am gene. in the work reported here, a synthetic 17-mer corresponding to the deduced sequence was shown to hybridize strongly to a 9-kb hindiii fragment from n. crassa wild-type dna but not to any corresponding fragment from the dna of a ...19826299898
characterization of a 45-kda polypeptide as the precursor of subunit 1 of cytochrome c oxidase in neurospora a previous paper (van 't sant, p., mak, j.f.c. and kroon, a.m. (1981) eur. j. biochem. 121, 21-26) we showed the existence of three elongated precursor proteins (45, 36 and 25 kda) of mitochondrial translation products in neurospora crassa. we presented some indications that the largest precursor could be related to subunit 1 of cytochrome c oxidase. here we present conclusive evidence that the 45-kda polypeptide is indeed this precursor by demonstrating that an immunodetectable 45-kda polype ...19836299357
mitochondrial dna sequences in the nuclear genome of a locust.the endosymbiotic theory of the origin of mitochondria is widely accepted, and implies that loss of genes from the mitochondria to the nucleus of eukaryotic cells has occurred over evolutionary time. however, evidence at the dna sequence level for gene transfer between these organelles has so far been limited to a single example, the demonstration that a mitochondrial atpase subunit gene of neurospora crassa has an homologous partner in the nuclear genome. from a gene library of the insect, locu ...20076298629
calcium inhibition of a heat-stable cyclic nucleotide phosphodiesterase from neurospora crassa.neurospora crassa had a heat-stable (up to 95 degrees c), soluble cyclic nucleotide phosphodiesterase (pde). both unheated and heat-stable pde activities were inhibited by micromolar concentrations of ca2+. this inhibition was reversed by egta or edta in molar excess of the ca2+ concentration. calmodulin was not involved in the ca2+ inhibition, nor was ca2+ inhibition of the heat-stable pde due to cleavage inactivation of the enzyme by a ca2+-stimulated protease. in addition to ca2+, several oth ...19836298002
[properties of polyphosphate phosphohydrolase of the "leaky" mutant neurospora crassa with respect to the specific enzyme].some properties of polyphosphate phosphohydrolase from n. crassa strain ad-6.28610a and from its mutant with a decreased polyphosphate phosphohydrolase activity were compared. it was shown that the ph optimum for both enzyme species lies within the range of 7.1-7.3; the temperature optimum is 45 degrees. the mutant polyphosphate phosphohydrolase has a v value, which is 2 times less than that of the parent strain, and possesses a higher thermal inactivation stability. the enzymes of both cultures ...19826297621
adenosine kinase-deficient mutant of neurospora crassa.tubercidin-resistant mutant strains of neurospora crassa were isolated, and at least one appeared to be deficient in adenosine kinase. no significant differences in [8-14c]adenosine labeling of purine nucleotides or nucleosides were found between the wild type and the adenosine kinase-deficient strains.19826292168
the mitochondrially made subunit 2 of neurospora crassa cytochrome aa3 is synthesized as a precursor protein. 19826291999
folding of the mitochondrial proton adenosinetriphosphatase proteolipid channel in phospholipid vesicles.the mitochondrial h+-atpase proteolipid from neurospora crassa was incorporated into small unilamellar dimyristoylphosphatidylcholine vesicles and its conformation determined by circular dichroism spectroscopy (cd). while the largely alpha-helical conformation is relatively independent of the method of incorporation into vesicles, i.e., rehydration, detergent dialysis, or detergent dilution, the proteolipid conformation was significantly different in detergent micelles and in organic solvents. o ...19826291595
cloning of the trp-1 gene from neurospora crassa by complementation of a trpc mutation in escherichia coli.studies with a hybrid plasmid containing 4.0 kilobase pairs of neurospora crassa dna cloned into plasmid pbr322 indicated that the plasmid restored to prototrophy a trpc mutant of escherichia coli which lacked phosphoribosyl anthranilate isomerase but not a trpc mutant which lacked indole glycerol phosphate synthetase, that the relevant transcription was initiated at a promoter within the n. crassa dna, and that the phosphoribosyl anthranilate isomerase could be specified by a subcloned segment ...19826290461
isolation of mitochondrial porin from neurospora crassa. 19826290266
biosynthesis of mitochondrial porin and insertion into the outer mitochondrial membrane of neurospora crassa.mitochondrial porin, the major protein of the outer mitochondrial membrane is synthesized by free cytoplasmic polysomes. the apparent molecular weight of the porin synthesized in homologous or heterologous cell-free systems is the same as that of the mature porin. transfer in vitro of mitochondrial porin from the cytosolic fraction into the outer membrane of mitochondria could be demonstrated. before membrane insertion, mitochondrial porin is highly sensitive to added proteinase; afterwards it i ...19826290213
structural role of the tyrosine residues of cytochrome c.the tertiary structures of horse, tuna, neurospora crassa, horse [hse65,leu67]- and horse [hse65,leu74]-cytochromes c were studied with high-resolution 1h n.m.r. spectroscopy. the amino acid sequences of these proteins differ at position 46, which is occupied by phenylalanine in the horse proteins but by tyrosine in the remaining two, and at positions 67, 74 and 97, which are all occupied by tyrosine residues in horse and tuna cytochrome c but in the other proteins are substituted by phenylalani ...19826289807
reduction of exogenous cytochrome c by neurospora crassa conidia: effects of superoxide dismutase and blue light.the reduction of externally added cytochrome c by neurospora crassa conidia was observed. the reduction was stimulated by antimycin a and suppressed partially by superoxide dismutase. when conidia were treated with diethyldithiocarbamate, which inactivated endogenous superoxide dismutase, the cytochrome c reduction was stimulated. blue light also stimulated the cytochrome c reduction. azide, which inhibits photochemical reactions mediated by flavins, suppressed the blue light effect. superoxide ...19826288655
cyclic nucleotide phosphodiesterase activities in neurospora crassa.cyclic nucleotide phosphodiesterase activities in soluble neurospora crassa mycelial extracts were resolved into two peaks, phosphodiesterase i and ii, by chromatography on deae-cellulose columns. phosphodiesterase i hydrolysed cyclic amp and cyclic gmp equally well. phosphodiesterase ii was active on cyclic gmp but scarcely active on cyclic amp. phosphodiesterase i was resolved by gel filtration and sucrose-density-gradient centrifugation into three peaks having molecular weights of about 57 00 ...19826288007
mechanisms for chromosomal aberrations in mammalian cells.experimental evidence is presented for the involvement of dna double-strand breaks in the formation of radiation-induced chromosomal aberrations. when x-irradiated cells were post-treated with single-strand specific neurospora crassa endonuclease (ne), the frequencies of all classes of aberration increased by about a factor 2. under these conditions, the frequencies of dna double-strand breaks induced by x-rays (as determined by neutral sucrose-gradient centrifugation), also increased by a facto ...19826287256
protein kinase activities in neurospora crassa. molecular properties. 19826287207
biogenesis of mitochondrial ubiquinol:cytochrome c reductase (cytochrome bc1 complex). precursor proteins and their transfer into mitochondria.the precursor proteins to the subunits of ubiquinol:cytochrome c reductase (cytochrome bc1 complex) of neurospora crassa were synthesized in a reticulocyte lysate. these precursors were immunoprecipitated with antibodies prepared against the individual subunits and compared to the mature subunits immunoprecipitated or isolated from mitochondria. most subunits were synthesized as precursors with larger apparent molecular weights (subunits i, 51,500 versus 50,000; subunit ii, 47,500 versus 45,000; ...19826286652
[specific activity and molecular forms of nad-kinase in neurospora crassa ontogeny].the specific activity and molecular forms of nad-kinase during ontogenesis of neurospora crassa were investigated. the specific activity of the enzyme increased drastically at critical stages of fungal development, i.e. during conidia germination and during transition from the logarithmic to stationary growth stage, reaching 85 nmole nadp/hr/mg protein. by polyacrylamide gel electrophoresis four forms of nad-kinase were revealed that had the following molecular masses: i-338,000, ii-306,000, iii ...20066285331
genetic and enzymatic characterization of the inducible glycerol dissimilatory system of neurospora crassa.the glycerol dissimilatory system in neurospora crassa was analyzed through the characterization of 18 glp- mutants which were isolated after inositol-less death and filtration enrichment. all mutants obtained by this procedure could be assigned to one of three complementation groups. the subsequent genetic characterization of these glp mutations revealed lesions on the i, ii, and vi chromosomes at the glp-1, glp-2, and glp-4 loci, each of which was subjected to fine-structure analysis. evidence ...19826284716
1h nmr studies of eukaryotic cytochrome c. resonance assignments and iron-hexacyanide-mediated electron exchange.1h nmr resonance assignments in the spectra of horse, tuna, neurospora crassa and candida krusei cytochromes c are described. assignments have been made using nmr double-resonance techniques in conjunction with electron-exchange experiments, spectral comparison of related proteins, and consideration of the x-ray structure of tuna cytochrome c. resonances arising from 11 residues of horse cytochrome c have been assigned.19826284503
similar genes for a mitochondrial atpase subunit in the nuclear and mitochondrial genomes of neurospora crassa. 19826283377
identification and isolation of actin from neurospora crassa.crude cell extracts of neurospora crassa contained an abundant protein that was identified as actin by a number of criteria. the protein, either in cell extracts or in pure form, co-migrated with rabbit skeletal muscle actin in polyacrylamide gels. the n. crassa actin was purified by deae-cellulose and dnaase i-sepharose chromatography and had the expected property of inhibiting dnaase i activity. although n. crassa actin could polymerize and depolymerize, purification based entirely on this cha ...19826281363
cytochrome oxidase subunit iii gene in neurospora crassa mitochondria. location and sequence.we have located and sequenced the gene for cytochrome oxidase subunit iii (coiii) in neurospora crassa mitochondria. the coiii gene is located downstream from the small rrna gene within a cluster of trna genes and is coded by the same strand as the trna and the rrna genes. like the trna and the rrna genes, the coiii gene is also flanked by the gc-rich palindromic dna sequences which are highly conserved in n. crassa mitochondria. the coiii coding sequence predicts a protein 269 amino acids long ...19826279664
transformation of neurospora crassa utilizing recombinant plasmid dna. 19826279089
isolation and properties of a cyclic amp-binding protein from neurospora. evidence for its role as the regulatory subunit of cyclic amp-dependent protein kinase.a cyclic amp-binding protein with a native molecular weight calculated to be 82,000 was purified 2,000-fold from neurospora crassa. the apparent subunit molecular weight was 47,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting that the native protein exists as a dimer of identically sized subunits. the 8-n3-cyclic [32p]amp-labeled protein appeared as a doublet upon two-dimensional gel electrophoresis, with pi = 5.4 and 5.5. binding studies with both noncyclic and cycli ...19826277955
larger precursors of mitochondrial translation products in neurospora crassa. indications for a precursor of subunit 1 of cytochrome c oxidase.specific labeling in vivo of the formylated n termini of mitochondrial translation products revealed that some mitochondrially synthesized proteins were not labeled this way. as a consequence, it was worthwhile considering that larger precursor proteins of mitochondrial translation products exist. although we used a rapid isolation procedure, only after 2-h of labeling in the presence of cycloheximide, could three additional mitochondrial translation products (molecular mass 45, 36, and 25 kilod ...19816276171
gene cloning in neurospora crassa. 19826276097
highly conserved gc-rich palindromic dna sequences flank trna genes in neurospora crassa sequencing a 2200 bp region of the neurospora crassa mitochondrial dna encoding the 3' end of the large rrna gene and a cluster of six trna genes, we have found that the trna genes are flanked by highly conserved gc-rich palindromic dna sequences. an 18 bp long core sequence, 5'-cc ctgcag ta ctgcag gg-3', containing two closely spaced pst i sites, is common to all these palindromic sequences. each of the eight pst i sites mapped in the 2200 bp region consists of two closely spaced pst i sites ...19816276013
s1 nuclease does not cleave dna at single-base mis-matches.three assays have been designed to detect the cleavage of duplex phi x174 dna at single-base mis-matches. studies with s1 nuclease failed to detect cleavage at mis-matches. s1 nuclease digestion at 37 and 55 degrees c failed to produce a preferential degradation of a multiply mis-matched heteroduplex when compared to a mis-match-free homo-duplex as analyzed by sedimentation on sucrose gradients. other heteroduplex templates were not cleaved by s1 nuclease at a defined single-base mis-match when ...19816274410
mutational variants of the neurospora crassa nadp-specific glutamate dehydrogenase altered in a conformational equilibrium. 19816273586
purification & characterization of two forms of 5'amp nucleotidase form neurospora crassa. 19816273305
purification and identification of calmodulin from neurospora crassa. 19816273221
identification and characterization of recombinant plasmids carrying the complete qa gene cluster from neurospora crassa including the qa-1+ regulatory gene.the early reactions in the catabolism of quinic acid in neurospora crassa are controlled by at least four genes which are clustered on linkage group vii. three of the loci (qa-2, qa-4, and qa-3) encode enzymes that convert quinic acid to protocatechuic acid. the fourth gene (qa-1) encodes a positive regulatory protein which, in the presence of quinic acid, leads to the de novo synthesis of the other proteins in the qa cluster. this communication describes a series of recombinant plasmids that sp ...19816272290
cytochrome c oxidase in cytochrome c oxidase-deficient mutant strains of neurospora crassa.three mutant strains of neurospora crassa, previously characterized as cytochrome c oxidase deficient, were found to possess this respiratory enzyme. the mitochondrial cytochrome contents of logarithmic phase cells of wild type (74a) and the respiration-deficient strains mi-3, cya-4-23, and cya-5-34 were investigated with low temperature difference spectrophotometry; two of the strains were found to possess cytochrome a. cytochrome c oxidase catalytic activity measurements performed on isolated ...19816270105
mitochondrial biogenesis during fungal spore germination: respiration and cytochrome c oxidase in neurospora crassa.the germination of conidiospores of wild-type neurospora crassa was found to be dependent upon the function of the cytochrome-mediated electron transport pathway. the cyanide-insensitive alternate oxidase did not contribute significantly to the respiration of these germinating spores. the dormant spores contained all of the cytochrome components and a catalytically active cytochrome c oxidase required for the activity of the standard respiratory pathway, and these preserved components were respo ...19816268605
evidence for the involvement of a rapidly turning over protease in the degradation of cytochrome oxidase in neurospora crassa. 19816268065
cloning the quinic acid (aq) gene cluster from neurospora crassa: identification of recombinant plasmids containing both qa-2+ and qa-3+.a 22.2-kb insert of neurospora crassa dna containing at least two of the genes from the inducible catabolic quinic acid pathway has been cloned into the cosmid vehicle phc79 resulting in a recombinant plasmid, pmsk308. the qa-2+ locus (which encodes catabolic dehydroquinase) is functionally expressed in both escherichia coli and qa-2 mutants of n. crassa transformed with pmsk308 plasmid dna. expression of the qa-3 gene (which encodes quinate dehydrogenase) is only detected upon reintroduction in ...19816266928
membrane-bound and water-soluble cytochrome c1 from neurospora mitochondria.cytochrome c1 is a subunit of ubiquinol--cytochrome c reductase (ec in neurospora crassa wild type 74a grown in the presence of chloramphenicol, the subunit is inserted only into the bilayer of the mitochondrial inner membranes without associating with other proteins. from these modified membranes a monodisperse (cytochrome c1)-triton complex was isolated by subjecting the triton-solubilized membranes to affinity chromatography on immobilized cytochrome c. a water-soluble pentamer of ...19816265210
[camp participation in the light regulation of carotenoid synthesis in neurospora crassa]. 19816265179
a novel extranuclear mutant of neurospora with a temperature-sensitive defect in mitochondrial protein synthesis and mitochondrial atpase.[c93] is a novel, extranuclear mutant of neurospora crassa which has a normal mitochondrial phenotype when grown at 25 degrees, but which is deficient in cytochromes b and aa3 when grown at 37 degrees (pittenger and west 1979). in the present work, the phenotype of [c93] was characterized in greater detail. when [c93] is grown at 37 degrees, the rate of mitochondrial protein synthesis is decreased to approximately 25% that of wild type; the ratio of mitochondrial small to large ribosomal subunit ...19816261083
purification and some properties of nad-glycohydrolase from conidia of neurospora crassa.nad-glycohydrolase from conidia of neurospora crassa was purified by affinity chromatography, using 4-methylnicotinamide adenine dinucleotide as ligand immobilized onto sepharose through a hydrophilic spacer arm. the pure enzyme is a glycoprotein with an isoelectric point of 5.5 and a molecular weight of 33 000 as determined by sodium dodecylsulphate gel electrophoresis. the specific activity is the highest so far found for nad-glycohydrolases and in various aspects the enzyme is different from ...19816260480
protein kinase activities in neurospora crassa. 19816260035
role of heme in the synthesis of cytochrome c oxidase in neurospora crassa.the role of heme in the synthesis of cytochrome c oxidase has been investigated in the mold neurospora crassa. iron-deficient cultures of the mold have low levels of cytochrome oxidase and delta-aminolevulinate dehydratase, the latter being the rate-limiting enzyme of the heme-biosynthetic pathway in this organism. addition of iron to the iron-deficient cultures results in an immediate increase in the levels of delta-aminolevulinate dehydratase followed by an increase in the rate of heme synthes ...19806254961
mapping of mitochondrial structural genes in neurospora crassa.a hybridization method has been employed to study the organization of the mitochondrial genome of neurospora crassa. the method involves the use of 5' end-labeled single-stranded restriction fragments obtained from cytoplasmic "petite" strains of saccharomyces cerevisiae known to contain single mitochondrial genes. the presence and localization of genes homologous to subunits 1, 2, and 3 of cytochrome oxidase, cytochrome b and subunit 6 of the atpase is thus established for the mitochondrial gen ...19806253481
cyclic amp-dependent protein kinase of neurospora crassa. 19806251816
acetylglutamate kinase. a mitochondrial feedback-sensitive enzyme of arginine biosynthesis in neurospora crassa.the radioisotopic method used to assay acetylglutamate kinase (ec of neurospora crassa has been shown to detect two distinct enzymatically catalyzed reactions. the enzymes were separated by differential centrifugation into a cytosolic activity and an organellar activity. both activities required atp and were thermal-labile. the cytosolic activity was insensitive to inhibition by arginine and formed a stable reaction product in the absence of hydroxylamine. the organellar activity had an ...19806251078
assembly of the mitochondrial membrane system. sequences of yeast mitochondrial trna genes.two cytoplasmic "petite" (rho-) clones of saccharomyces cerevisiae have been selected for the retention of the aspartic acid trna gene. the two clones, designated ds200/a102 and ds200/a5, have tandemly repeated segments of mitochondrial dna (mtdna) with unit lengths of 1,000 and 6,400 base pairs, respectively. the ds200/a102 genome has a single trna gene with a 3'-cug-5' anticodon capable of recognizing the 5'-gac-3' and 5'-gau-3' codons for aspartic acid. the mtdna segment of ds200/a102 has bee ...19806251074
inhibition of udp-n-acetylglucosamine pyrophosphorylase by uridine.udp-n-acetylglucosamine pyrophosphorylases (utp: 2-acetamido-2-deoxy-alpha-d-glucose-1-phosphate uridylyltransferase, ec from baker's yeast and neurospora crassa ifo 6178 were inhibited by uridine which is the nucleoside moiety of udp-glcnac. the inhibition was shown in both directions of pyrophosphorolysis and of synthesis of udp-glcnac. kinetic analysis revealed that uridine demonstrated a noncompetitive type of inhibition with udp-glcnac and competitive inhibition with ppi. the ki v ...19806250624
distribution of sequences common to the 25--28s-ribonucleic acid genes of xenopus laevis and neurospora crassa.the extent of homology between the nucleotide sequence of l-rrna (the major rna component of the larger ribosomal subparticle) of a lower eukaryote (neurospora crassa) and an amphibian (xenopus laevis) was investigated by utilizing rdna (dna coding for rrna) of x. laevis cloned in plasmids pmb9 and pml2, and rdna of n. crassa cloned in bacteriophage lambda. hybridization studies revealed that sequences common to both n. crassa and x. laevis l-rrna comprise a total of approx. 1050 /+- 200 nucleot ...19806250536
intracellular localization, isolation and characterization of two distinct varieties of superoxide dismutase from neurospora crassa.1. neurospora crassa was found to contain two distinct superoxide dismutases. 2. most of the activity is associated with the cytosolic fraction and was shown to be the cu/zn-containing form of the protein. 3. mitochondria isolated from neurospora crassa showed two distinct superoxide dismutases: a cyanide-sensitive cu/zn-containing protein and a cyanide-insensitive form which probably contains manganese. 4. localization experiments, using selective marker enzymes and digitonin fractionation, ind ...19806249266
[isolation and certain features of a polyphosphate phosphohydrolase deficient mutant of the fungus neurospora crassa].a polyphosphatase deficient mutant of neurospora crassa has been isolated. the criterion for selecting the mutant was the capacity of the fungus to assimilate polyphosphates as the source of exogenous phosphorus. the mutant like the parent strain ad-6, was an adenine auxotroph but differed from the parent strain by a lower growth rate though, at the stationary stage, its biomass reached the same level as in the strain ad-6. the character of changes in the activity of polyphosphatase in the cours ...20166248740
the electron spin resonance spectrum of a suicidal fungus.the electron spin resonance spectrum of a suicidal inositol auxotroph of neurospora crassa, previously used as a model of cellular aging, exhibits a high-spin fe(iii) signal whose intensity increases as a function of the mutant's "senescence". surprisingly, the intensity of the signal is further enhanced by the exogenous antioxidant nordihydroguaiaretic acid, which reportedly decreases the rate of senescence.19806248694
physical map of aspergillus nidulans mitochondrial genes coding for ribosomal rna: an intervening sequence in the large rrna cistron.a detailed map of the 32 kb mitochondrial genome of aspergillus nidulans has been obtained by locating the cleavage sites for restriction endonucleases pst i, bam h i, hha i, pvu ii, hpa ii and hae iii relative to the previously determined sites for eco r i, hind ii and hind iii. the genes for the small and large ribosomal subunit rnas were mapped by gel transfer hybridization of in vitro labelled rrna to restriction fragments of mitochondrial dna and its cloned eco r i fragment e3, and by elect ...19806246396
the neurospora plasma membrane ca2+ pump.plasma membrane vesicles isolated from the eukaryotic microorganism neurospora crassa by the concanavalin a method catalyze mg2+-atp dependent 45ca2+ accumulation. since the atp-responsive vesicles are functionally inverted, the ca2+ transport system presumably operates as a ca2+ exit pump in the intact cell. the mechanism of the ca2+ pump system involves two components: 1) an electrogenic, proton-translocating atpase (ec, which utilizes the chemical energy of atp hydrolysis to generate ...19806245937
isolation and characterization of neurospora crassa mutants impaired in feedback control of ornithine synthesis.thirty-two independent mutants were isolated which overcame the proline requirement of pro-3 mutations in neurospora crassa. the mutations were not revertants, appeared to be allelic, were closely linked or allelic to arg-6, and in strains unable to degrade ornithine no longer suppressed the proline requirement. the suppressor mutations did not alter the levels of biosynthetic or catabolic enzymes, yet allowed accumulation of ornithine. suppressed strains unable to degrade arginine still produce ...19806245066
enzymatic trimethylation of residue-72 lysine in cytochrome c. effect on the total structure.a highly purified protein methylase iii from neurospora crassa or saccharomyces cerevisiae specifically methylates a single lysine residue of position 72 of horse heart cytochrome c. the enzymatically methylated cytochrome c has been separated from the unmethylated counterpart species by isoelectric focusing. simultaneously, the pi values of these two species were found to be 9.49 and 10.03, respectively. since methyl substitution increases the basicity associated with the epsilon-amino group of ...19806244857
carbamyl phosphate synthetase a of neurospora crassa.carbamyl phosphate synthetase a of neurospora crassa was partially purified from mitochondrial extracts. it is an extremely unstable enzyme (t 1/2 = 45 min at 25 detrees c) made up of two unequal subunits. the native enzyme has a molecular weight of approximately 175,000, and the large subunit has a molecular weight of about 125,000. both the native enzyme and its large subunit are quite asymmetric, as revealed by slow sedimentation in sucrose gradents (7.3s and 6.6s, respectively). the small su ...19806243618
an enzymatic alteration secondary to adenylyl cyclase deficiency in the cr-1 (crisp) mutant of neurospora crassa: nicotinamide adenine dinucleotide (phosphate) glycohydrolase overproduction. 19806243107
heat-sensitive mutant strain of neurospora crassa, 4m(t), conditionally defective in 25s ribosomal ribonucleic acid production.a heat-sensitive mutant strain of neurospora crassa, 4m(t), was studied in an attempt to define its molecular lesion. the mutant strain is inhibited in conidial germination and mycelial extension at the nonpermissive temperature (37 degrees c). macromolecular synthesis studies showed that both ribonucleic acid (rna) and protein syntheses are inhibited when 4-h cultures are shifted from 20 to 37 degrees c. density gradient analysis of ribosomal subunits made at 37 degrees c indicated that strain ...19816242828
cellular and extracellular siderophores of aspergillus nidulans and penicillium chrysogenum.aspergillus nidulans and penicillium chrysogenum produce specific cellular siderophores in addition to the well-known siderophores of the culture medium. since this was found previously in neurospora crassa, it is probably generally true for filamentous ascomycetes. the cellular siderophore of a. nidulans is ferricrocin; that of p. chrysogenum is ferrichrome. a. nidulans also contains triacetylfusigen, a siderophore without apparent biological activity. conidia of both species lose siderophores ...19816242827
studies on the induction of aryl hydrocarbon(benzo[a]pyrene) hydroxylase in neurospora crassa, and its suppression by sodium selenite.six fungal species were grown in the presence of benzo[a]pyrene (bp); four showed benzo[a]pyrene hydroxylase (aryl hydrocarbon hydroxylase, ahh) activity. penicillium sp. and neurospora crassa metabolized bp to a limited extent. n. crassa ahh activity was induced by bp, the major product of metabolism being 3-hydroxy-bp. both induction of ahh activity and metabolism of bp were suppressed by sodium selenite in the growth medium. two polypeptides, unique to bp-grown cells, were revealed by two-dim ...19846241764
molecular characterization of the qa-4 gene of neurospora crassa.the qa-4 gene of neurospora crassa encodes 3-dehydroshikimate dehydratase, which catalyzes the third step of the quinic acid (qa) catabolic pathway. the enzyme has previously been purified and characterized as a monomer of approx. 37 kdal. the nucleotide sequence of the qa-4 gene is presented here and the amino acid composition and tentative nh2-terminal sequence confirm the identification of the coding region within the qa-4 dna sequence. there are no introns in the qa-4 coding region. by s1 nu ...19846241580
preparation of a cell-free translation system from a wild-type strain of neurospora crassa and translation of pyruvate kinase messenger rna.a cell-free in vitro translation system exhibiting high activity has been developed from wild-type neurospora crassa mycelium. the isolation is simple and fast, and the homogenization does not appear to affect the activity of mycelial proteases and nucleases. this system is capable of supporting efficient translation of exogenously added homologous rna as demonstrated by the experiments with pk-specific mrna. in addition, it translates heterologous rna efficiently, shown by the translation of gl ...19846240997
structure of the cell wall proteogalactomannan from neurospora crassa. ii. structural analysis of the polysaccharide part.the native proteoheteroglycan (phg) from mycelia of neurospora crassa contain two kinds of carbohydrate chains differing structure. the oligosaccharides containing mannose and galactofuranose are attached by o-glycosidic linkages to serine or threonine residues in the protein (j. biochem. 96, 1005-1011, 1984). the second kind of carbohydrate chain is a polysaccharide containing mannose and galactofuranose as the main sugar components. the results of structural studies with methylation and nmr an ...19846240491
structure of the cell wall proteogalactomannan from neurospora crassa. i. purification of the proteoheteroglycan and characterization of alkali-labile oligosaccharides.proteoheteroglycan (phg) was prepared from neurospora crassa cells by extraction with hot water followed by cetyltrimethylammoniumbromide fractionation. the polymer was purified by deae-cellulose chromatography followed by gel filtrations. the phg was fractionated into five subfractions containing carbohydrate (65-88%), protein (19-36%), and a trace amount of phosphate (0.3-1.9%). the sugar compositions of the fractions were similar to each other (d-mannose, 47-60%, d-galactose, 35-50%, d-glucos ...19846240490
chitosomes from the wall-less "slime" mutant of neurospora crassa.cell-free extracts from the wall-less slime mutant of neurospora crassa and the mycelium of wild type exhibit similar chitin synthetase properties in specific activity, zymogenicity and a preferential intracellular localization of chitosomes. the yield of chitosomal chitin synthetase from slime cells was essentially the same irrespective of cell breakage procedure (osmotic lysis or ballistic disruption)--an indication that chitosomes are not fragments of larger membranes produced by harsh (balli ...19846240239
purification of the neurospora crassa plasma membrane h+-atpase by high-pressure liquid chromatography in the presence of sodium dodecyl sulfate.current methods for purifying the mr 100,000 h+-atpase from the plasma membrane of fungi and higher plants rely on detergent solubilization followed by density gradient centrifugation. the procedure yields catalytically active enzyme of high purity but takes several days, and the yields are low. for chemical studies on the primary structure of this enzyme, an alternative more rapid procedure was sought. in this paper a method which uses a high-performance gel filtration column in the presence of ...19846240211
dna-dna and dna-protein crosslinking and repair in neurospora crassa following exposure to nitrogen mustard.a new method was developed for the analysis of dna-protein crosslinks in neurospora crassa. the formations of dna-protein and dna-dna crosslinks were assayed following exposure of spheroplasts to hn2. both types of crosslink were detected and were found to be repaired during recovery. moreover a mutant sensitive to hn2 was defective in the removal of both types of crosslink.20156239978
photoregulation of some enzymes from neurospora crassa.light-grown cultures of neurospora crassa showed photoregulation of a number of enzymes. proteases and cytosolic malate dehydrogenase showed an increase in activity. there was a decrease in the activity of mitochondrial malate dehydrogenase, isocitrate dehydrogenase and cytosolic glucose-6p-dehydrogenase, isocitrate dehydrogenase and isocitrate lyase.19846239788
regulation of amino acid utilization in neurospora crassa: effect of nmr-1 and ms-5 mutations.the effect of the nmr-1 and ms-5 mutations, which lead to insensitivity to glutamine-mediated nitrogen metabolite repression, was examined with respect to extracellular deaminase production by neurospora crassa. deaminase production normally requires nitrogen limitation, but these mutations eliminated this requirement and allowed production of deaminase activity under nitrogen metabolite repressing conditions. demonstration of normal glutamine transport by both strains eliminated the possibility ...19846238946
nitrogen regulation of amino acid utilization by neurospora crassa.the production of an extracellular deaminase activity involved with the utilization of amino acids as sole sources of nitrogen is under the control of the nit-2 locus of neurospora crassa. this locus is the sole major nitrogen regulatory locus described for n. crassa and is believed to encode a positive effector required for induction of activities involved with the utilization of alternate nitrogen sources. production of deaminase activity requires the lifting of nitrogen metabolite repression, ...19846238945
a two-dimensional immunoelectrophoretic analysis of the heat-shock response exhibited by neurospora crassa cells.the heat-shock (hs) response of neurospora crassa was studied by two-dimensional (2-d) immunoelectrophoresis, in conjunction with in vivo labelling of proteins with [35s]methionine. antisera against extracts of normally grown and shocked cells were tested with both extracts as antigens. the resolution of normal cell proteins by interaction with homologous antisera yielded at least 35 immunoprecipitates. using antisera to shocked cells with normal and shocked cell extracts resolved four heat-shoc ...19846238661
two intervening sequences in the atpase subunit 6 gene of neurospora crassa. a short intron (93 base-pairs) and a long intron that is stable after excision.a 3590 base-pair region of the mitochondrial genome of neurospora crassa, including the gene for atpase subunit 6 (oli2), has been sequenced. the oli2 gene is interrupted by two intervening sequences. the first intron, situated after the third codon of the gene, is 93 base-pairs long; two-thirds of this intron consist of a palindromic sequence. the second intron is 1370 base-pairs long and contains an extended open reading frame that is continuous and in frame with the upstream exon sequence. th ...19846238172
processing peptidase of neurospora mitochondria. two-step cleavage of imported atpase subunit 9.subunit 9 (dicyclohexylcarbodiimide binding protein, 'proteolipid') of the mitochondrial f1f0-atpase is a nuclearly coded protein in neurospora crassa. it is synthesized on free cytoplasmic ribosomes as a larger precursor with an nh2-terminal peptide extension. the peptide extension is cleaved off after transport of the protein into the mitochondria. a processing activity referred to as processing peptidase that cleaves the precursor to subunit 9 and other mitochondrial proteins is described and ...19846237909
a basal unit of valine-sensitive acetolactate synthase of neurospora crassa.valine-sensitivity as well as activity of acetolactate synthase of neurospora crassa was stabilized with 1.2 m potassium phosphate buffer during extraction from mitochondria and early stages of purification, and with 20% glycerol plus 5 mm sodium pyruvate during sephadex g200 gel chromatography. the enzyme was expressed as four molecular species having the molecular weights of about 500,000, 140,000, 68,000 and 51,000, respectively. the first and the third species showed valine-sensitivity, but ...19846237648
in vitro reconstitution of nitrate reductase activity of the neurospora crassa mutant nit-1: specific incorporation of molybdopterin.the reduced, metal-free pterin of the molybdenum cofactor has been termed molybdopterin. oxidation of any molybdopterin-containing protein in the presence or absence of iodine yields oxidized molybdopterin derivatives termed form a and form b, respectively. application of these procedures to whole cells and cell extracts has demonstrated the presence of molybdopterin in wild-type neurospora crassa, and its absence in the cofactor-deficient mutant nit-1. in order to demonstrate that the reconstit ...19846237611
carbon source regulation of nicotinamide adenine dinucleotide (phosphate) glycohydrolase in neurospora crassa: induction and repression of enzyme synthesis.synthesis and release of nad(p)ase by neurospora crassa wild type was studied in experiments in which mycelia grown in vogel minimal medium were transferred to media containing protein as the only carbon source. several results are presented suggesting that the nad(p)ase may be induced by the presence of protein in the culture medium. low concentrations of sucrose or glucose (0.1%), casamino acids or some amino acids such as methionine, cysteine, phenylalanine and tryptophan strongly repressed t ...19846237174
activation of neurospora crassa soluble adenylate cyclase by calmodulin.the soluble form of adenylate cyclase was extracted and purified from wild-type neurospora crassa mycelia. brain or n. crassa calmodulin significantly enhanced this enzyme activity in assay mixtures containing mg2+-atp as substrate. egta reverses this calmodulin activation.19846236798
uv-induced recessive lethals in uvs strains of neurospora which are deficient in uv mutagenesis.the frequencies of spontaneous and uv-induced recessive lethal mutations were compared for uv-sensitive and wild-type heterokaryons of neurospora crassa. these heterokaryons were homokaryotic either for one of two alleles of uvs-3, or for uvs-6 or uvs+. for uvs-3, which is known to have mutator effects, spontaneous recessive lethals were found to be 4-6 times more frequent than observed in uvs+. after correction for clonal distribution of spontaneous mutants, an observed 2-fold increase for uvs- ...19846236366
mutagenicity of neocarzinostatin in neurospora crassa.neocarzinostatin (ncs) is an acidic, single-chain polypeptide of 109 amino acids that has shown some antitumor activity in clinical trials. ncs is mutagenic in reca+ strains of escherichia coli, but not in reca strains; on the other hand, a defect in the nucleotide-excision-repair pathway has no effect on the mutagenicity of ncs in e. coli. similar results are seen in mammalian cells. excision-repair-deficient xeroderma pigmentosum (xp) cells repair ncs-induced dna damage at the same rate as rep ...19846236365
effects of neurospora nuclease halo (nuh) mutants on secretion of two phosphate-repressible alkaline deoxyribonucleases.various recently isolated nuh mutants of neurospora crassa (i.e., mutants which show reduced nuclease haloes on dna-sorbose plates flooded with hcl) were mapped in several new genes or gene clusters and checked for effects on dna repair and nuclease secretion. some of them were found to be sensitive to mms (methylmethane sulfonate) and sterile in meiosis. release of nuclease activities into filtrates of liquid cultures was analyzed by deae-sepharose chromatography. in the wild type, three alkali ...19846235804
a leucine trna gene adjacent to the qa gene cluster of neurospora crassa.a single trnaleu gene has been localized and sequenced from neurospora crassa. it is located only 375 bp from the qa gene cluster and it is the only trna or 5s rrna gene within this cloned 37 kb region. the gene encodes a trnaleu with the anti-codon aag, and unlike the other nuclear eukaryotic trnaleu (aag) gene sequenced (from c. elegans), contains an intervening sequence of 27 bp. the neurospora trnaleu (aag) is 84% and 73% homologous respectively to the c. elegans and bovine trnaleu (aag), an ...19846235483
accurate transcription of homologous 5s rrna and trna genes and splicing of trna in vitro by soluble extracts of neurospora.we have developed soluble extracts from neurospora crassa capable of accurately and efficiently transcribing homologous 5s rrna and trna genes. the extracts also appear to quantitatively end-process and splice the primary trna transcripts. although the extracts could not transcribe a heterologous (yeast) 5s rrna gene, they did transcribe a yeast trnaleu gene and slowly process the transcripts. in addition, we have developed a novel strategy for rapidly sequencing uniformly labelled rnas using ba ...19846235482
mobilization of vacuolar arginine in neurospora crassa. mechanism and role of glutamine.nitrogen starvation has been shown to increase the cytosolic arginine concentration and to accelerate protein turnover in mycelia of neurospora crassa. the cytosolic arginine is derived from a metabolically inactive vacuolar pool. redistribution of arginine between cytosolic and vacuolar compartments is the result of mobilization of this metabolite in response to nitrogen starvation. mobilization of arginine (and purines) also occurred in response to glutamine limitation, but arginine accumulate ...19846235220
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