PMID(sorted descending)
control of arginine metabolism in neurospora crassa. role of feedback inhibition.flux through the arginine biosynthetic pathway of neurospora crassa was measured under a variety of physiological conditions. flux persisted, although at a reduced rate, in mutant strains resistant to feedback inhibition even after prolonged growth in the presence of exogenous arginine. flux reverted to the uninhibited rate more quickly in feedback-resistant strains than in wild type strains upon removal of exogenous arginine. these results rule out enzyme repression as a major factor in control ...19862942539
biochemical comparison of the neurospora crassa wild-type and the temperature-sensitive leucine-auxotroph mutant leu-5. detailed kinetic comparison of the leucyl-trna synthetases.the cytoplasmic leucyl-trna synthetases were purified from a wild-type neurospora crassa and from a temperature-sensitive leucine-auxotroph (leu-5) mutant. a detailed steady-state kinetic study of the aminoacylation of the trnaleu from n. crassa by the purified synthetases was carried out. these enzymes need preincubation with dithioerythritol and spermine before the assay in order to become fully active. the kappm value for leucine was lowered by high atp concentrations and correspondingly the ...19862942399
biochemical comparison of the neurospora crassa wild type and the temperature-sensitive and leucine-auxotroph mutant leu-5. purification of the cytoplasmic and mitochondrial leucyl-trna synthetases and comparison of the enzymatic activities and the degradation patterns.the cytoplasmic leucyl-trna synthetases of neurospora crassa wild type (grown at 37 degrees c) and mutant (grown at 28 degrees c) were purified approximately 1770-fold and 1440-fold respectively. additional enzyme preparations were carried out with mutant cells grown for 24 h at 28 degrees c and transferred then to 37 degrees c for 10-70 h of growth. the mitochondrial leucyl-trna synthetase of the wild type was purified approximately 722-fold. the mitochondrial mutant enzyme was found only in tr ...19862942398
the effect of papulacandin b on (1----3)-beta-d-glucan synthetases. a possible relationship between inhibition and enzyme conformation.the antibiotic, papulacandin b, inhibited growth or (1----3)-beta-d-glucan synthetase (or both) in the fungi saccharomyces cerevisiae, hansenula anomala, neurospora crassa, cryptococcus laurentii, schizophyllum commune and wangiella dermatitidis. no effect was observed on achlya ambisexualis. there was no apparent correlation between the inhibition of growth and that of the synthetase. with most of the fungal extracts, the inhibition of glucan synthetase by papulacandin b became less pronounced ...19862942248
the properties of arginine transport in vacuolar membrane vesicles of neurospora crassa.we have measured the uptake of arginine into vacuolar membrane vesicles from neurospora crassa. arginine transport was found to be dependent on atp hydrolysis, mg2+, time, and vesicle protein with transported arginine remaining unmodified after entry into the vesicles. the mg2+ concentration required for optimal arginine transport varied with the atp concentration so that maximal transport occurred when the mgatp2- concentration was at a maximum and the concentrations of free atp and mg2+ were a ...19862941421
heat shock protects germinating conidiospores of neurospora crassa against freezing injury.germinating conidiospores of neurospora crassa that were exposed to 45 degrees c, a temperature that induces a heat shock response, were protected from injury caused by freezing in liquid nitrogen and subsequent thawing at 0 degrees c. whereas up to 90% of the control spores were killed by this freezing and slow thawing, a prior heat shock increased cell survival four- to fivefold. survival was determined by three assays: the extent of spore germination in liquid medium, the number of colonies t ...19862941411
a cloned tryptophan-synthesis gene from the ascomycete cochliobolus heterostrophus functions in escherichia coli, yeast and aspergillus nidulans.a gene (trp1) in the tryptophan biosynthetic pathway of the fungal plant pathogen cochliobolus heterostrophus was isolated by complementation of an escherichia coli trpf mutant which lacked phosphoribosylanthranilate isomerase (prai) activity. the cloned gene also complemented an e. coli trpc mutant lacking indoleglycerolphosphate synthase (igps) activity, a yeast trp1 mutant missing prai activity and an aspergillus nidulans trpc mutant. it functioned in e. coli and a. nidulans without apparent ...19862941339
a study of the messenger rna encoding pyruvate kinase of neurospora neurospora crassa, there is a single pyruvate kinase (pk) consisting of four identical subunits of approximately 60k daltons. northern and dot blot hybridization studies, using most of the yeast pyruvate kinase gene as a probe, suggest the presence of two distinct mrna species for pyruvate kinase, separable on the basis of the length of their polyadenylated tails, by oligo(dt)cellulose chromatography. these messages are present in polysomes, immuno-precipitated by anti-pk antibodies, indicati ...19862941081
rearrangement mutations on the 5' side of the qa-2 gene of neurospora implicate two regions of qa-1f activator-protein interaction.transcriptional activation of the neurospora crassa qa genes normally requires the positive regulatory gene, qa-1f+, whose function is controlled by the inducer quinic acid and by the product of the negative regulatory gene, qa-1s+. the properties of qa-1f+ activator have been examined in transcriptional mutations of the qa-2 structural gene, in which activator-independent transcription of qa-2 (qa-2ai mutants) occurs in strains having a qa-1f- gene. seven qa-2ai mutants with dna rearrangements ...19862940595
n-acetyl-l-glutamate synthase of neurospora crassa. characteristics, localization, regulation, and genetic control.n-acetylglutamate synthase, an early enzyme of the arginine pathway, provides acetylglutamate for ornithine synthesis in the so-called "acetylglutamate cycle." because acetylglutamate is regenerated as ornithine is formed, the enzyme has only a catalytic or anaplerotic role in the pathway, maintaining "bound" acetyl groups during growth. we have detected this enzyme in crude extracts of neurospora crassa and have localized it to the mitochondria along with other ornithine biosynthetic enzymes. t ...19862939069
effect of chloramphenicol and ethidium bromide on the level of ornithine carbamoyltransferase in neurospora crassa.the specific activity of the nuclear-gene-encoded, mitochondrial arginine biosynthetic enzyme ornithine carbamoyltransferase (ec in neurospora crassa was elevated in mycelia treated with chloramphenicol or ethidium bromide. the increase in specific activity was caused by an increase in the number of mature enzyme molecules rather than by the activation of a preexisting enzyme. chloramphenicol and ethidium bromide appeared to act indirectly via arginine-mediated derepression. however, de ...19862939061
magnification of rrna gene number in a neurospora crassa strain with a partial deletion of the nucleolus organizer.some progeny from crosses between the neurospora crassa translocation strain t(il----vl)oy321 and normal sequence n. crassa strains are duplication strains with a partial deletion of the nucleolus organizer. despite the deletion, these progeny are viable and produce a functional nucleolus. quantification of rrna gene number in these deletion progeny demonstrated a significant loss of rrna genes, down to 60% of the parental wild-type level. initially, all of these reduced nucleolus organizer (rno ...19862938894
neurospora crassa mitochondria contain two forms of a 4'-phosphopantetheine-modified protein.when neurospora crassa was labeled with [14c]pantothenic acid during growth, the mitochondrial fraction contained two bands of radioactivity of mr 19,000 and 22,000 by sodium dodecyl sulfate gel electrophoresis. the 19-kda band was converted to the 22-kda band by four treatments which are characteristic of the cleavage of a thioester bond: dithiothreitol and 2-mercaptoethanol at basic but not neutral ph, alkaline methanolysis, sodium borohydride in tetrahydrofuran, and hydroxylamine at neutral p ...19862937780
evidence for a pterin-derivative associated with the molybdenum cofactor of neurospora crassa nitrate reductase. 19852937070
depression of enzyme synthesis in response to arginine limitation in neurospora crassa.ornithine carbamoyltransferase and argininosuccinase, two enzymes involved in arginine synthesis, are regulated by cross-pathway amino acid control in neurospora and show derepression in response to limitation of any one of a number of amino acids. the effects of varying the severity of arginine limitation upon the synthesis of these enzymes, in mycelial cultures of an arginine auxotrophic strain, are reported here. depression occurred at arginine concentrations sufficient to allow normal rates ...19852936866
isolation and characterization of the aspergillus niger trpc gene.the aspergillus niger trpc gene was isolated by complementation experiments with an escherichia coli trpc mutant. plasmid dna containing the a. niger trpc gene transforms an aspergillus nidulans mutant strain, defective in all three enzymatic activities of the trpc gene, to trp+, indicating the presence of a complete and functional trpc gene. southern blot analysis of dna from these trp+ transformants showed that plasmid dna was present but that this dna was not integrated at the site of the chr ...19852936650
inhibitory effect of the partially resolved coordination isomers of chromic desferricoprogen on coprogen uptake in neurospora crassa.two partially resolved chromatographic fractions of geometrical and optical isomers of the chromic complexes of desferricoprogen, a siderophore from neurospora crassa, were obtained from high-pressure liquid chromatography on a reverse-phase matrix. the first fraction was identified as a cis complex with a 20% diastereomeric excess of the lambda isomer. the second fraction was identified as a mixture of several of the possible trans isomers with a net 20% diastereomeric excess of the delta isome ...19862934378
a new ultraviolet-light sensitive mutant of neurospora crassa with unusual photoreactivation property.a mutant, uvs-(sa3b), which shows high sensitivity to uv light segregated among the progeny in a back-cross of a presumptive mms-sensitive mutant to a wild-type strain. at 37% survival, this mutant was approximately 5 times more sensitive to uv and also 6 times more sensitive to 4-nqo than the wild type. but it was only slightly sensitive to gamma-ray, mms, mnng, mtc and histidine. it showed an unusual photoreactivation response. its time course of photorecovery was similar to the photoreactivat ...20132933585
structural studies on neurospora rna polymerases and associated proteins.extensive structural homology between the three nuclear rna polymerases of neurospora crassa has been observed by peptide and immunological analyses. within each polymerase, we found structural similarity between subunits in the 65- to 75-kda range and one of the two large subunits. we observed also that polymerase ii, as isolated, is associated with a 700-kda complex of 12 polypeptides which is localized in the nucleus. a 75-kda subunit of the 700-kda complex was found to be structurally relate ...19852933407
purification of the three nuclear rna polymerases from neurospora crassa.nuclear rna polymerases i, ii, and iii from neurospora crassa have been purified 3,000-, 1,500-, and 10,000-fold, respectively, by a procedure that minimizes proteolysis of the 220-kda subunit of polymerase ii. the neurospora enzymes resemble, in polypeptide composition, the corresponding polymerases isolated from other eukaryotes. the 220-kda subunit of neurospora polymerase ii cross-reacts with antisera directed against the 220-kda subunits of type ii polymerases from drosophila and wheat germ ...19852933406
recessive mutations from natural populations of neurospora crassa that are expressed in the sexual diplophase.wild-collected isolates of neurospora crassa shear and dodge were systematically examined for recessive mutations affecting the sexual phase of the life cycle, which is essentially diploid. seventy-four of 99 wild-collected isolates from 26 populations in the united states, india and pakistan carried one or more recessive mutations that reduced fertility significantly when homozygous; mutations affecting spore morphology were also detected. limited complementation tests indicate that most of the ...19852933298
mitochondrial translation of subunits of the rotenone-sensitive nadh:ubiquinone reductase in neurospora crassa.the rotenone sensitive nadh:ubiquinone was isolated from mitochondria of neurospora crassa as a monodisperse preparation with the apparent mol. wt. in triton solution of 0.9 x 10(6). the enzyme is composed of at least 22 subunits with apparent mol. wts. in sds between 70 and 11 kd. six of the subunits with the mol. wts. 70, 48, 37, 25, 22 and 18 kd were radioactively labelled in the enzyme isolated from cells which had incorporated [35s]methionine in the presence of cycloheximide. these subunits ...19852933252
carbamoyl-phosphate synthetases from neurospora crassa. immunological relatedness of the enzymes from neurospora, bacteria, yeast, and mammals.neurospora crassa contains two carbamoyl-phosphate synthetases: a mitochondrial enzyme (cps-a) which supplies carbamoyl phosphate for arginine biosynthesis, and a nuclear enzyme whose product is used for the synthesis of pyrimidines. we have prepared antiserum against a highly purified preparation of the large subunit of cps-a and have used the antiserum to demonstrate that the large subunit is, like most mitochondrially localized proteins, initially synthesized as a higher molecular weight prec ...19852932445
gamma-ray induced ageing mutants of neurospora crassa: response to some antioxidants and chloramphenicol. 19852932387
nucleotide sequence of the gdh gene coding for the nadp-specific glutamate dehydrogenase of saccharomyces cerevisiae.the isolation of the saccharomyces cerevisiae gene for nadp-dependent glutamate dehydrogenase (nadp-gdh) by cross hybridization to the neurospora crassa am gene, known to encode for nadp-gdh is described. two dna fragments selected from a yeast genomic library in phage lambda gt11 were shown by restriction analysis to share 2.5 kb of common sequence. a yeast shuttle vector (cv13) carrying either to the cloned fragments complements the gdh- strain of s. cerevisiae and directs substantial overprod ...19852932370
isolation and structural organization of the neurospora crassa copper metallothionein gene.the neurospora crassa copper metallothionein gene was cloned and its complete nucleotide sequence is reported. enriched metallothionein mrna was used as a template for cdna synthesis, primed by a metallothionein-specific, synthetic undecanucleotide. the sequence of the cdna obtained allowed the synthesis of a unique 21-mer which was used to screen a genomic dna library of n. crassa. in agreement with the published amino acid sequence, the gene codes for a polypeptide 26 amino acid residues in le ...19852932331
evidence for a 2-oxoglutarate dehydrogenase complex activity in mitochondria of neurospora crassa and compared localization with the pyruvate dehydrogenase complex.a 2-oxoglutarate dehydrogenase complex activity is demonstrated in neurospora crassa mitochondria. a submitochondrial fractionation by digitonin treatment followed by freeze-thawing enables measurement of a well preserved activity in the mitochondrial matrix. in contrast to other reports, the pyruvate dehydrogenase activity is also found to be localized in the matrix.19852932166
gene organization and regulation in the qa (quinic acid) gene cluster of neurospora crassa. 20092931582
preparation of functional group analogs of unsaturated fatty acids and their effects on the circadian rhythm of a fatty-acid-deficient mutant of neurospora crassa.functional group analogs of oleic, linoleic and linolenic acids were prepared by coverting their double bonds to dibromo, cyclopropyl, epoxy, methoxy, and, in the case of oleic acid, hydroxy groups. these compounds were supplemented to the bd csp cel strain of the mold neurospora crassa. the cel mutation confers a partial requirement for saturated fatty acids and, also, perturbs the circadian rhythm of spore formation. for example, the period of bd csp cel's rhythm is dramatically lengthened upo ...20082931204
primary structure of cucumber (cucumis sativus) ascorbate oxidase deduced from cdna sequence: homology with blue copper proteins and tissue-specific expression.cdna clones for ascorbate oxidase were isolated from a cdna library made from cucumber (cucumis sativus) fruit mrna. the library was screened with synthetic oligonucleotides that encode the nh2-terminal sequence of this enzyme. nucleotide sequence analysis of the cloned cdna inserts revealed a 1761-base-pair open reading frame that encoded an nh2-terminal signal peptide of 33 amino acids and a mature enzyme of 554 amino acids (mr, 62,258). the amino acid sequence deduced from nucleotide sequence ...19892919172
large-scale purification of plasma membrane h+-atpase from a cell wall-less mutant of neurospora crassa. 19882906720
purification of vacuolar membranes, mitochondria, and plasma membranes from neurospora crassa and modes of discriminating among the different h+-atpases. 20102906719
molecular cloning and characterization of a negative-acting nitrogen regulatory gene of neurospora crassa.expression of the structural genes of the nitrogen control circuit of neurospora crassa is regulated by the positive-acting nit-2 control gene and by the negative-acting nmr control gene. nitrate reductase is expressed in a constitutive fashion in nmr mutant strains, which appear to be largely insensitive to nitrogen catabolite repression. thus, nmr mutants are sensitive to chlorate in the presence of ammonia or glutamine, whereas the wild type is chlorate resistant under these conditions. a cos ...19882906403
the fluorescein isothiocyanate-binding site of the plasma-membrane h+-atpase of neurospora crassa.the mammalian (na+,k+), ca2+-, and (h+,k+)-atpases contain a well-characterized lysine residue that reacts with fluorescein 5'-isothiocyanate (fitc); enzymatic activity is protected by atp, suggesting that the residue is located in or near the nucleotide-binding domain. in this study, the plasma-membrane h+-atpase of neurospora crassa is also shown to be sensitive to fitc. the reaction occurs with pseudo first-order kinetics, has a pka of 8.0, and is stimulated by mg2+. enzymatic activity is pro ...19882904434
protein chemistry of the neurospora crassa plasma membrane h+-atpase.a highly effective procedure for fragmenting the neurospora crassa plasma membrane h+-atpase and purifying the resulting peptides is described. the enzyme is cleaved with trypsin to form a limit digest containing both hydrophobic and hydrophilic peptides, and the hydrophobic and hydrophilic peptides are then separated by extraction with an aqueous ammonium bicarbonate solution. the hydrophilic peptides are fractionated by sephadex g-25 column chromatography into three pools, and the individual p ...20102903697
the plasma membrane h+-atpase of neurospora crassa. properties of two reactive sulfhydryl groups.previous work with n-ethylmaleimide (nem) has defined two sites on the neurospora plasma membrane h+-atpase. modification of one (the "fast" site) by nem is rapid but does not affect atpase activity, while modification of the other (the "slow" site) inactivates the enzyme and is protectable by mgatp or mgadp. in the present study, a wider array of sulfhydryl reagents have been used to examine the properties of both sites. the results show the following. (a) both fast and slow sites react prefere ...19882903147
biosynthesis of the plasma membrane h+-atpase of neurospora crassa.the plasma membrane h+-atpase of neurospora is a 100-kda integral membrane protein which appears, on the basis of hydropathy analysis of its amino acid sequence, to span the lipid bilayer at least eight times. to investigate the assembly and processing of the atpase, a full-length cdna has been constructed for use in in vitro transcription and translation experiments. comparison of three different forms of the atpase (nascent protein, nascent protein cotranslationally inserted into membranes, an ...19882902084
studies on the import into mitochondria of yeast atp synthase subunits 8 and 9 encoded by artificial nuclear fusions have been constructed between each of subunits 8 and 9 from mitochondrial atpase of saccharomyces cerevisiae, proteins normally encoded inside mitochondria, and the cleavable n-terminal transit peptide from the nuclearly encoded precursor to subunit 9 of neurospora crassa mitochondrial atpase. the subunit 8 construct was imported efficiently into isolated yeast mitochondria and was processed at or very near the fusion point. when expressed in vivo from its artificial nuclear gene, ...19882900779
molecular cloning and analysis of the regulation of cys-14+, a structural gene of the sulfur regulatory circuit of neurospora crassa.the cys-14+ gene encodes sulfate permease ii, which is primarily expressed in mycelia. cys-14+ is one of a set of sulfur-related structural genes under the control of cys-3+ and scon+, the regulatory genes of the sulfur control circuit. we have cloned cys-14+ from a cosmid library of neurospora crassa dna. a restriction fragment length polymorphism analysis showed that this clone maps to the region of chromosome iv corresponding to the cys-14+ locus. northern blot analyses were used to examine t ...19882898097
reprogrammed expression of subunit 9 of the mitochondrial atpase complex of saccharomyces cerevisiae. expression in vitro from a chemically synthesized gene and import into isolated mitochondria.a synthetic gene has been designed and constructed by total chemical synthesis as a first step in the functional relocation from the mitochondrion to the nucleus of a gene encoding subunit 9 of the yeast mitochondrial atpase complex. this gene (nap9) incorporates codons frequently used in nuclear genes of saccharomyces cerevisiae and additionally includes a series of unique restriction enzyme cleavage sites to facilitate future systematic manipulations of the gene and its protein product. follow ...19882895707
assembly of functional proton-translocating atpase complex in yeast mitochondria with cytoplasmically synthesized subunit 8, a polypeptide normally encoded within the organelle.a mitochondrial gene from saccharomyces cerevisiae encoding a hydrophobic membrane protein, subunit 8 of the f0/f1-type mitochondrial atpase complex, has been functionally replaced by an artificial nuclear gene specifying an imported version of this protein. the experiments reported here utilized a multicopy expression vector (plf1) that replicates in the nucleus of yeast cells and that carries an inserted dna segment, specifying a precursor protein (n9/y8) consisting of subunit 8 fused to an n- ...19882895470
secondary structure of the neurospora crassa plasma membrane h+-atpase as estimated by circular a previous communication, a water-soluble, hexameric form of the neurospora crassa plasma membrane h+-atpase was described (chadwick, c. c., goormaghtigh, e., and scarborough, g. a. (1987) arch. biochem. biophys. 252, 348-356). to facilitate physical studies of the hexamers, the h+-atpase isolation procedure has been improved, resulting in a structurally and functionally stable hexamer preparation that contains only 5 to 10% non-atpase protein, approximately 12 mol of enzyme-bound lysophospha ...19882893796
clathrin coated vesicles in neurospora crassa.electropherograms of neurospora crassa homogenates showed a polypeptide with a mobility slightly lower than that of a standard sample of clathrin (from bovine brain). subcellular fractionation of the homogenate resulted in a 20-fold enrichment of the putative n. crassa clathrin in the microsomal fraction. further fractionation of the microsomal fraction by glass bead permeation chromatography yielded a fraction enriched about 150-fold relative to the homogenate. coated vesicles (42.5 +/- 2.5 nm ...19872892127
mutation of a conserved glycine residue modifies the vanadate sensitivity of the plasma membrane h+-atpase from schizosaccharomyces pombe.the structural gene pma+1 for the h+-atpase from the fission yeast schizosaccharomyces pombe has been isolated and sequenced. the intron-less gene encodes for a protein of mr = 99,769 which is 75% homologous to those of saccharomyces cerevisiae and neurospora crassa. the s. pombe pma+1 gene complements not only s. pombe pma-1-1 but also s. cerevisiae pma-1-4 mutants selected for in vitro vanadate-resistant atpase activity. the sequence of the s. pombe mutant pma-1-1 allele reveals that the glyci ...19872891694
molecular cloning and analysis of the regulation of nit-3, the structural gene for nitrate reductase in neurospora crassa.the nit-3 gene of neurospora crassa encodes the enzyme nitrate reductase and is regulated by nitrogen catabolite repression and by specific induction with nitrate. the nit-3 gene was isolated from a cosmid-based genomic library by dual selection for benomyl resistance and for the ability to complement a nit-3 mutant strain using the sibling-selection procedure. the nit-3 gene was subcloned as a 3.8-kilobase dna fragment from a cosmid that carried an approximately 40-kilobase n. crassa dna insert ...19872891138
relationship between two major immunoreactive forms of arginase in neurospora crassa.two major immunoreactive proteins of mr 41,700 and 36,100 have been detected in crude mycelial extracts with polyclonal antibodies raised against arginase purified from neurospora crassa. the latter corresponded to the protein used to obtain the antibodies. both polypeptides were either missing or present in very low amounts in mutant strains having little or no detectable arginase activity. the relative proportion of the two species was altered in strains containing the nitrogen catabolite regu ...19872890621
isolation of telomere dna from neurospora crassa.the most distal known gene on neurospora crassa linkage group vr, his-6, was cloned. a genomic walk resulted in isolation of the telomere at vr. it was obtained from a library in which the endmost nucleotides of the chromosome had not been removed by nuclease treatment before being cloned, and mapping indicates that the entire chromosome end has probably been cloned. sequences homologous to the terminal 2.5 kilobases of dna from vr from these oak ridge n. crassa strains are found at other sites ...19872890097
circadian rhythms in neurospora crassa: a clock mutant, prd-1, is altered in membrane fatty acid composition.the fatty acid compositions of the phospholipids of neurospora crassa mutants with altered periods were determined to test the possibility that some of these mutants might have altered membrane composition. in liquid shaker culture in constant light the bd (band) strain, which has a normal period (21.6 h), exhibited a growth-dependent increase in linoleic acid content and a decrease in linolenic acid content during early log phase growth. by late log phase, fatty acid composition was essentially ...19872889471
molecular cloning and characterization of the cys-3 regulatory gene of neurospora crassa.the regulatory gene cys-3+ controls the synthesis of a number of enzymes involved in sulfur metabolism. cys-3 mutants show a multiple loss of enzymes in different pathways of sulfur metabolism. the cys-3+ gene was isolated by transformation of an aro-9 qa-2 cys-3 inl strain with a clone bank followed by screening with the "sib selection" method. the library used (pral1) contained inserts of sau3a partial digest fragments of about 9 kilobases as well as the neurospora qa-2+ gene. double selection ...19872886908
characterization of nit-2, the major nitrogen regulatory gene of neurospora crassa.the nit-2 gene is the major nitrogen-regulatory gene of neurospora crassa, and under conditions of nitrogen limitations, it turns on the expression of various unlinked structural genes which specify nitrogen-catabolic enzymes. the nit-2 gene was subcloned as a 6-kilobase (kb) dna fragment from a cosmid that carried approximately a 40-kb n. crassa dna insert. the nit-2 gene was localized in a dna segment of approximately 3.5 kb and was shown to correspond to a unique dna sequence located on linka ...19872885741
isolation and characterization of coated vesicles from filamentous fungi.coated vesicles have been shown to exist in neurospora crassa (ascomycetes) and uromyces phaseoli (basidiomycetes) growing germlings. separation of coated vesicles in both fungi was obtained when the high-speed (100,000g) pellet was fractioned on a sephacryl s-1000 gel filtration column, according to the procedure of mueller and branton. electron micrographs of negatively stained coated vesicles from fractions of gel filtration show the same striking lattice coated vesicles similar to vertebrate ...19872885195
studies on nitrate reductase of clostridium perfringens. iv. identification of metals, molybdenum cofactor, and iron-sulfur cluster.nitrate reductase of clostridium perfringens was purified by an improved method using immuno-affinity chromatography. the purified preparation contained mo, fe, and acid-labile sulfide; the mo content was 1 mol per mol and the fe 3.7 mol per mol of the enzyme. the inactive enzyme obtained from cells grown in the presence of tungstate did not hold mo but contained 1 mol of w. the content of fe was not increased. the presence of molybdenum cofactor in the nitrate reductase was indicated by the for ...19872884214
human liver cdna clones encoding proteolipid subunit 9 of the mitochondrial atpase complex.clones encoding the proteolipid subunit 9 of the mitochondrial atpase complex have been isolated from a lambda gt10 library of human liver cdna sequences, using a probe of neurospora crassa cdna encoding subunit 9. from nucleotide sequence analysis it is concluded that the amino acid sequence of mature human subunit 9 is identical to that of its bovine counterpart. by comparing the sequence of two cdna clones (denoted human 1 and 2) to those of two bovine cdna clones (denoted p1 and p2) recently ...19872883974
location of a dicyclohexylcarbodiimide-reactive glutamate residue in the neurospora crassa plasma membrane h+-atpase.the proton pump (h+-atpase) found in the plasma membrane of the fungus neurospora crassa is inactivated by dicyclohexylcarbodiimide (dccd). kinetic and labeling experiments have suggested that inactivation at 0 degrees c results from the covalent attachment of dccd to a single site in the mr = 100,000 catalytic subunit (sussman, m. r., and slayman, c. w. (1983) j. biol. chem. 258, 1839-1843). in the present study, when [14c]dccd-labeled enzyme was treated with the cleavage reagent, n-bromosuccin ...19872881924
yeast mitochondrial atpase subunit 8, normally a mitochondrial gene product, expressed in vitro and imported back into the organelle.subunit 8 of yeast mitochondrial f1f0-atpase is a proteolipid made on mitochondrial ribosomes and inserted directly into the inner membrane for assembly with the other f0 membrane-sector components. we have investigated the possibility of expressing this extremely hydrophobic, mitochondrially encoded protein outside the organelle and directing its import back into mitochondria using a suitable n-terminal targeting presequence. this report describes the successful import in vitro of atpase subuni ...19862881782
a hexameric form of the neurospora crassa plasma membrane isolated by our recently developed large-scale procedure, the neurospora plasma membrane h+-atpase exists as a homogeneous, oligomeric complex of 105,000-da monomers with a molecular mass equivalent to a spherical protein of about 1 million da, as judged by its behavior during chromatography on calibrated columns of sepharose cl-6b and cl-4b. treatment of this complex with the nonionic detergent, tween 20, followed by sepharose column chromatography in the presence of this detergent produces ...19872880563
the atp synthase subunit 9 gene of aspergillus nidulans: sequence and transcription.we have determined the nucleotide sequence of the aspergillus nidulans nuclear gene olic31, which encodes subunit 9 of mitochondrial atp synthase. the open reading frame contains no introns and specifies a predicted protein of 143 amino acids comprising a pre-sequence of 62 residues and a mature protein of 81 residues. the amino acid homology with the equivalent neurospora crassa protein is 50% for the pre-sequence and 80% for the mature protein. a comparison with this and other imported mitocho ...19862880279
molecular cloning of nit-2, a regulatory gene required for nitrogen metabolite repression in neurospora crassa.we used an efficient sib-selection procedure to isolate a cosmid clone that complemented a mutated nit-2 gene of neurospora crassa. restriction fragment length polymorphism mapping indicated that the cosmid dna insert was derived from linkage group il, between 5s rdna locus 12 and mt, the region of the n. crassa genome that contains nit-2. we conclude that the cosmid carries the nit-2 gene.20102879771
primary structure of the neurospora plasma membrane h+-atpase deduced from the gene sequence. homology to na+/k+-, ca2+-, and k+-atpase.the gene for the neurospora crassa plasma membrane h+-atpase has been cloned and sequenced. the gene encodes for a protein of 920 amino acids with a molecular weight of 100,002. the coding region is interrupted by four introns: three near the amino terminus and one near the carboxyl terminus. the deduced amino acid sequence of the n. crassa plasma membrane h+-atpase exhibits 75% homology to the amino acid sequence of the saccharomyces cerevisiae plasma membrane h+-atpase. also, an amino acid com ...19862876992
amino acid sequence of the plasma membrane atpase of neurospora crassa: deduction from genomic and cdna sequences.the plasma membrane of neurospora crassa contains an electrogenic h+-atpase (ec, for which we have isolated and sequenced both genomic and cdna clones. the atpase gene is interrupted by four small introns (58-124 base pairs). it encodes a protein of 920 amino acids (mr, 99,886) possessing as many as eight transmembrane segments. the neurospora atpase shows significant amino acid sequence homology with the na+,k+- and ca2+-transporting atpases of animal cells, particularly in regions th ...19862876429
topological studies suggest that the pathway of the protons through f0 is provided by amino acid residues accessible from the lipid phase.the structure of the f0 part of atp synthases from e. coli and neurospora crassa was analyzed by hydrophobic surface labeling with [125i]tid. in the e. coli f0 all three subunits were freely accessible to the reagent, suggesting that these subunits are independently integrated in the membrane. labeled amino acid residues were identified by edman degradation of the dicyclohexylcarbodiimide binding (dccd) proteins from e. coli and neurospora crassa. the very similar patterns obtained with the two ...19862874840
interactions of neurospora crassa plasma membrane h+-atpase with n-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline.the carboxyl group activating reagent n-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline (eedq) interacts with the neurospora plasma membrane h+-atpase in at least three different ways. this reagent irreversibly inhibits atp hydrolysis with kinetics that are pseudo-first-order at several concentrations of eedq, and an appropriate transform of these data suggests that 1 mol of eedq inactivates 1 mol of the h+-atpase. inhibition probably involves activation of an atpase carboxyl group followed by a ...19862874829
characterization of an essential arginine residue in the plasma membrane h+-atpase of neurospora crassa.treatment of the plasma membrane h+-atpase of neurospora crassa with the arginine-specific reagents phenylglyoxal or 2,3-butanedione at 30 degrees c, ph 7.0, leads to a marked inhibition of atpase activity. mgatp, the physiological substrate of the enzyme, protects against inactivation. mgadp, a competitive inhibitor of atpase activity with a measured ki of 0.11 mm, also protects, yielding calculated kd values of 0.125 and 0.115 mm in the presence of phenylglyoxal and 2,3-butanedione, respective ...19862874143
pantothenate is required in neurospora crassa for assembly of subunit peptides of cytochrome c oxidase and atpase/atp polypeptide subunit of cytochrome c oxidase (ec and two subunits of the atpase/atp synthase (ec in mitochondria of neurospora crassa are covalently modified with a derivative of pantothenic acid. in asexual spores of a pantothenate auxotroph of neurospora, deprivation of pantothenic acid blocked the increase of the specific activities of cytochrome c oxidase and the atpase above the basal activities in the dormant spores. under cellular panthothenate deprivation, all the s ...19862872672
oxidation of neurospora crassa glutamine synthetase.the glutamine synthetase of neurospora crassa, either purified or in cell extracts, was inactivated by ascorbate plus fecl3 and by h2o2 plus feso4. the inactivation reaction was oxygen dependent, inhibited by mncl2 and edta, and stimulated in cell extracts by sodium azide. this inactivation could also be brought about by adding nadph to the cell extract. the alpha and beta polypeptides of the active glutamine synthetase were modified by these inactivating reactions, giving rise to two novel acid ...19862872202
labeling of individual amino acid residues in the membrane-embedded f0 part of the f1 f0 atp synthase from neurospora crassa. influence of oligomycin and dicyclohexylcarbodiimide.three f0 subunits and the f1 subunit beta of the atp synthase from neurospora crassa were labeled with the lipophilic photoactivatable reagent 3-(trifluoromethyl)-3-(m-[125i]iodophenyl)diazirine ([125i]tid). in the proteolipid subunit which was the most heavily labeled polypeptide labeling was confined to five residues at the nh2-terminus and five residues at the c-terminus of the protein. labeling occurred at similar positions compared with the homologous protein (subunit c) in the atp synthase ...19862869944
light-regulated protein and poly(a)+ mrna synthesis in neurospora crassa.we have examined the effect of illumination upon the patterns of protein synthesis in the filamentous ascomycete neurospora crassa by pulse labelling and two-dimensional gel electrophoresis. light did not affect overall rates of protein synthesis but did induce the synthesis of six novel polypeptides whose appearance followed a temporally regulated pattern. when translation products of mrna from illuminated cultures and dark control cultures were compared it was found that the synthesis of five ...19852868891
regulation of glutamine synthesis by glycine and serine in neurospora crassa.the biosynthetic activities of the polypeptide subunits alpha and beta of glutamine synthetase (gs) were inhibited in vitro by glycine and serine. these amino acids inhibited the growth of a mutant strain with partial gs activity when grown on glutamate as the nitrogen source and also blocked the synthesis of the glutamine in vivo, thus demonstrating the inhibitory effect on gs activity in vivo. glycine and serine lowered the intracellular glutamine pool and regulated gs beta synthesis. a prefer ...20092867084
circadian rhythms in neurospora crassa: the effects of point mutations on the proteolipid portion of the mitochondrial atp synthetase.five oligomycin-resistant (olir) mutant strains of neurospora crassa were analyzed for their growth rate and for the periodicity of their circadian rhythm. the most resistant strains had periods of 18-19 h while the least resistant strain had a normal period of 21.0 h. there was a rough correlation between the in vivo degree of oligomycin-resistance and the amount of change in the period. several of the olir mutations have been previously described by sebald et al. (1977) in terms of known amino ...20102863735
size of the plasma membrane h+-atpase from neurospora crassa determined by radiation inactivation and comparison with the sarcoplasmic reticulum ca2+-atpase from skeletal muscle.using radiation inactivation, we have measured the size of the h+-atpase in neurospora crassa plasma membranes. membranes were exposed to either high energy electrons from a van de graaff generator or to gamma irradiation from 60co. both forms of radiation caused an exponential loss of atpase activity in parallel with the physical destruction of the mr = 104,000 polypeptide of which this enzyme is composed. by applying target theory, the size of the h+-atpase in situ was found to be approximatel ...19852862141
functional effects and cross-reactivity of antibody to purified subunit b (uncf protein) of escherichia coli proton-atpase.subunit b (uncf protein) of the proton-atpase (f1f0) of escherichia coli was purified from membranes of strain an1460 (unc+). antibody to purified subunit b was raised in rabbits. it reacted with f1-depleted membranes and blocked f1 binding. bound antibody had no effect on proton transport through f0. f1-depleted membranes competed with purified subunit b for antibody in an enzyme-linked immunosorbent assay. f1-depleted membranes which had been pretreated with trypsin or preincubated with satura ...19852857549
omega-amidase pathway in the degradation of glutamine in neurospora crassa.evidence for the participation of the glutamine transaminase-omega-amidase pathway in the utilization of glutamine in neurospora crassa was obtained. its participation is indicated by the in vitro activities of glutamine transaminase and omega-amidase, the in vivo accumulation of alpha-ketoglutaramate when an inhibitor of transamidases is present, and the inhibition by aminooxyacetic acid and 6-diazo-5-oxo-l-norleucine of the ammonium excreted in the presence of glutamine by a mutant strain that ...19852857167
the isolation of demolybdo xanthine oxidase from bovine was deduced many years ago from indirect evidence that demolybdo xanthine oxidase is present in normal bovine milk. this has now been confirmed by isolation of this enzyme form by a method based on the folate-gel affinity-chromatography procedure described nishino & tsushima [(1986) j. biol. chem. 261, 11242-11246]. enzymic and spectroscopic properties of demolybdo xanthine oxidase, which retains flavin and iron-sulphur centres, are generally in accordance with expectations. like the normal e ...19882850803
role of cytochrome c heme lyase in the import of cytochrome c into mitochondria.the import of cytochrome c into neurospora crassa mitochondria was examined at distinct stages in vitro. the precursor protein, apocytochrome c, binds to mitochondria with high affinity and specificity but is not transported completely across the outer membrane in the absence of conversion to holocytochrome c. the bound apocytochrome c is accessible to externally added proteases but at the same time penetrates far enough through the outer membrane to interact with cytochrome c heme lyase. format ...20092848813
cyclic nucleotide phosphodiesterase activity in neurospora crassa. purification by immunoaffinity chromatography and characterization.monoclonal antibodies to neurospora crassa cyclic nucleotide phosphodiesterase (pde i) were selected by their capacity to inhibit the enzyme activity. the monoclonal immunoglobulin, coupled to sepharose 4b, was used for the affinity purification of pde i activity. after sds-polyacrylamide gel electrophoresis the affinity purified pde i fractions showed a single polypeptide band of about 41 kda. this band reacted in western blots with the above mentioned monoclonal immunoglobulin.19882848723
the heat shock response of neurospora crassa: stress-induced thermotolerance in relation to peroxidase and superoxide dismutase levels.heat shock and other treatments, including cadmium chloride, hydrogen peroxide and sodium arsenite, led to the induction of high levels of peroxidase activity as well as thermotolerance in neurospora crassa. no correlation was apparent between superoxide dismutase levels and development of thermotolerance following exposure to these stress conditions. a prominent role for peroxidase in protection against damage by toxic products of oxygen is suggested.19882847725
isolation of genes encoding the neurospora vacuolar atpase. analysis of vma-2 encoding the 57-kda polypeptide and comparison to partially purified preparations of the vacuolar atpase from neurospora crassa, the two most prominent components are polypeptides of mr = 70,000 and 60,000. we previously reported the isolation of the gene vma-1, which encodes the mr = 70,000 polypeptide, and presented evidence that the polypeptide contains the site of atp hydrolysis (bowman, e. j., tenney, k., and bowman, b. j. (1988) j. biol. chem. 263, 13994-14001). we now report the isolation of a gene (designated vma-2), that encodes the ...19882844751
cloning of mtr, an amino acid transport gene of neurospora crassa.translocation of neutral aliphatic and aromatic amino acids across the plasma membrane of the ascomycete neurospora crassa requires a functional gene product of the mtr locus. mutations at this locus are defective in transport of those amino acids. we have cloned the mtr+ gene of neurospora crassa from an ordered cosmid library of genomic dna and produced a preliminary restriction map of 2.9 kilobases of genomic dna that encompasses the mtr coding region. we have confirmed that the cloned dna re ...19882843424
dna sequence duplications trigger gene inactivation in neurospora crassa.transforming sequences are faithfully replicated in vegetative cells of neurospora but are typically subject at high frequency to sequence alterations and methylation in the period between fertilization and nuclear fusion. previous work showed a correlation between the occurrence of these radical changes, referred to by the acronym rip, and the presence of sequence duplications resulting from the introduced dna. various possible causes for the rip process were investigated. introduction of a sin ...20092842795
informational parameters and randomness of mitochondrial dna.the informational content of genomes of nuclear and mitochondrial origin is examined. by using the parameters of shannon's information theory the language of mitochondrial dna is shown to be more similar to the language of bacterial dna than to that of nuclear dna in more evolutionarily advanced animals. moreover, using the parameters of kolmogorov's theory on randomness, genes of different organisms (neurospora crassa and saccharomyces cerevisiae) coding for the same protein (subunit 9 of atpas ...19882842512
cytoplasmic leucyl-trna synthetase of neurospora crassa is not specified by the leu-5 locus.we generated a lambda gt11 neurospora crassa cdna library and screened the library for the cytoplasmic leucyl-trna synthetase (cyto leurs) clones using cyto leurs specific antibody. two clones, lambda nclrsc1 and lambda nclrsc2, were obtained which have inserts of approximately 2 kbp and approximately 1.3 kbp, and which overlap by about 0.6 kbp. the following lines of evidence indicate that lambda nclrsc1 and lambda nclrsc2 encode parts of cyto leurs. (1) antibodies affinity purified using eithe ...19882842224
transformation of neurospora crassa with circular and linear dna and analysis of the fate of the transforming dna.we have conducted a detailed study of 108 qa-2+ neurospora transformants which were obtained by use of circular plasmid dnas and various linear dnas. parallel genetic and molecular analyses have revealed that three classes of transformants can be identified: linked transformants, in which the qa-2 gene has integrated at the resident locus, unlinked transformants, where integration has occurred at other genomic sites, and a third class designated non-transmissible which fail to pass the qa-2 gene ...19852842071
cyclic amp-dependent, constitutive thermotolerance in the adenylate cyclase-deficient cr-1 (crisp) mutant of neurospora crassa.we investigated the heat shock response of the adenylate cyclase deficient mutant cr-1 (crisp) of neurospora crassa. this strain was observed to be much more resistant to a lethal temperature of 50 degrees c than the wild type. this constitutive thermotolerance was absent in cr-1 conidiospores raised on cyclic amp (camp, 2.5 mm) supplemented solid medium, but was partially restored when the conidiospores were germinated at 30 degrees c, a temperature which fails to induce thermotolerance in the ...19882841035
organization of the ribosomal rna genes of schizophyllum commune.the 18, 5.8, 25 and 5s ribosomal rna (rrna) cistrons have been mapped on the ribosomal dna (rdna) unit repeat of schizophyllum commune strain 4-40. these genes are spatially ordered in the sequence given. the presence of a large primary precursor rrna which is processed to form the mature 18, 5.8 and 25s rrnas has been demonstrated. we have mapped the site of transcriptional initiation for this rrna primary precursor. the sequence surrounding this site has been determined and shown to be highly ...19882841031
dnas of the two mating-type alleles of neurospora crassa are highly dissimilar.the mating-type alleles a and a of neurospora crassa control mating in the sexual cycle and function in establishing heterokaryon incompatibility in the vegetative cycle. the a and a alleles were cloned, and they were shown to encode both the sexual functions and vegetative incompatibility. the mating-type clones contain nonhomologous dna segments that are flanked by common dna sequences. neurospora crassa and all heterothallic and pseudohomothallic neurospora species contain a single copy of on ...19882840740
molecular cloning and physical mapping of the neurospora crassa 74-or23-1a mitochondrial provide for thorough sampling of the neurospora crassa mitochondrial genome for evolutionary studies, recombinant plasmids containing each of the ecori digestion fragments of the genome were assembled and used to map the locations of 89 additional restriction endonuclease cleavage sites, representing 10 newly mapped enzymes and 2 previously unmapped hincii sites. data used to locate new restriction sites were obtained from digestions of whole mitochondrial dna, digestions of the cloned ecori ...19852836095
nucleotide sequence of the mitochondrial cytochrome oxidase subunit ii gene in the yeast hansenula saturnus.the gene for subunit ii of cytochrome oxidase in the yeast hansenula saturnus was previously shown to be located on a 1.7 kb hindiii-bamhi fragment of mitochondrial dna (lawson and deters, accompanying paper). in this paper, we report the nucleotide sequence of a large part of this fragment, covering the coding region of the subunit ii gene, designated coxii, and its 5' and 3' flanking regions. the coding region of the coxii gene consists of a continuous open reading frame, 744 nucleotides long, ...19852836090
nucleotide sequence of the aspergillus niger trpc gene: structural relationship with analogous genes of other organisms.the nucleotide sequence of the aspergillus niger tryptophan c (trpc) gene was determined. northern hybridization and s1-mapping experiments showed the presence of a 2.6 kb trpc poly(a)+ rna with two very short (5 and 6 nucleotides) noncoding 5'-regions. comparison of the predicted amino acid sequence with that of trp gene proteins of pro- and eukaryotic organisms revealed three functional domains (g, c, f) in the a. niger trpc protein which catalyse the glutamine amidotransferase reaction (gat), ...19882836085
transformation of aspergillus niger using the homologous orotidine-5'-phosphate-decarboxylase gene.a homologous transformation system for the filamentous fungus aspergillus niger has been developed, based on the orotidine-5'-phosphate-decarboxylase gene. a. niger pyr- mutants have been selected from 5-fluoro-orotic acid resistant mutants. these mutants were found to comprise two complementation groups, pyra and pyrb. the a. niger omp-decarboxylase gene was isolated from a gene library by heterologous hybridization with the neurospora crassa pyr4 gene. the cloned gene is capable to transform a ...19872836081
sequence analysis of the ddpyr5-6 gene coding for ump synthase in dictyostelium discoideum and comparison with orotate phosphoribosyl transferases and omp decarboxylases.a dictyostelium discoideum dna fragment that complements the ura3 and the ura5 mutants of saccharomyces cerevisiae has been sequenced. it contains an open reading frame of 478 codons capable of encoding a polypeptide of molecular weight 52475. this gene, named ddpyr5-6, encodes a bifunctional protein composed of the orotate phosphoribosyl transferase (oprtase) and the orotidine-5'-phosphate decarboxylase (ompdecase) domains described for ump synthase in mammals. the existence of separate domains ...19882835631
neurospora crassa nuclear genome contains analogy of saccharomyces cerevisiae genes for ribosomal rna processing.neurospora crassa wild type genome shows dna sequences which are homologous to the sequences present in the rrna processing genes of the yeast saccharomyces cerevisiae. five such processing genes from yeast, viz., rna1 through rna5, cloned in plasmid pbr322 were transformed in escherichia coli strain le392. southern blots containing dnas from these clones were restricted with several restriction endonucleases along with dnas from lambda phage, rice (plant) and neuroblastoma (animal), were hybrid ...19872835180
identification and isolation of a putative permease gene in the quinic acid utilization (qut) gene cluster of aspergillus nidulans.mutations in the qutd gene of aspergillus nidulans cause the loss of ability to grow upon quinic acid as sole carbon source in media at normal ph 6.5 and failure to induce three enzyme activities specifically required for metabolism to protochatechuic acid. all 9 qutd mutants recovered are recessive and have been found to be ph sensitive, growing strongly on quinic acid media at ph 3.5 and producing significant induced enzyme activities. these properties are consistent with the hypothesis that t ...19872835177
transformation of neurospora crassa with the trp-1 gene and the effect of host strain upon the fate of the transforming dna.neurospora trp-1+ transformants, obtained by transforming a trp-1 inl strain with plasmid dna containing the wild type trp1+ gene, were characterized by genetic and southern blot analyses. the transforming trp-1 gene integrated at or near the resident site in all of the trp-1+ transformants obtained with circular dna or dna cut within the trp-1 coding region. the frequency of homologous integration decreased substantially when the donor dna was cleaved outside the trp-1 coding region. the transf ...19882834105
characterization of inl+ transformants of neurospora crassa obtained with a recombinant cosmid-pool.we constructed a neurospora crassa gene library in a cosmid vector and used the cosmid-pool dna to transform an inl, rg neurospora crassa strain to inositol prototrophy. the inl+ colonies obtained in this experiment proved to be integrative type transformants. genetic analysis revealed that the integration event occurred at or near the inl locus. in one of the transformants the inl+ trait exhibited mitotic and meiotic instability. in hybridization experiments free plasmids were detected in the f ...19862834083
isolation and identification of the aspergillus nidulans gdha gene encoding nadp-linked glutamate dehydrogenase.the neurospora crassa am gene was used as a heterologous probe to identify clones from two independently constructed aspergillus nidulans gene libraries. these clones have a common hindiii 1.85 kb fragment. this a. nidulans nucleotide stretch hybridises to a n. crassa 2.7 kb bamhi fragment of wild type dna but not to a co-migrating fragment from the dna of the n. crassa am132 deletion mutant. one a. nidulans clone was shown to complement the n. crasse am132 deletion strain. the n. crassa transfo ...19862834076
conservation of a long open reading frame in two neurospora mitochondrial plasmids.the nucleotide sequence of a specific region of the mitochondrial plasmid from the neurospora intermedia varkud-lc strain was determined. analysis of the sequence revealed the presence of a long (up to 710 amino acids) orf. this orf is almost identical to a previously characterized orf in the mitochondrial plasmid from the neurospora crassa mauriceville-lc strain. when the orfs from the two plasmids are compared over their entire length of 2,133 bp, only 34 nucleotide substitutions are found (gr ...19862832686
inversions and recombinations in mitochondrial dna of the (sg-1) cytoplasmic mutant in two neurospora species.the mitochondrial dnas of [sg-1] cytoplasmically-mutant and wild-type strains of neurospora crassa and neurospora sitophila were examined by comparative restriction endonuclease analyses. the mtdna of n. sitophila wild type of whitehouse differs from type ii mtdna of n. crassa by insertions of 3.3 kb in ecori-9, and 1.2 kb in ecori-3, and a deletion of 1.1 kb in ecori-5. these dna heteromorphisms provided convenient markers for tracing n. crassa [sg-1] mtdna during and after its transfer into n. ...19862832078
an endo-exonuclease activity of yeast that requires a functional rad52 gene.extracts of rad+ and radiation-sensitive (rad) mutants of the yeast saccharomyces cerevisiae were examined for total mg2+-dependent alkaline deoxyribonuclease activity and the presence of a nuclease that crossreacts immunologically with an antiserum raised against an endo-exonuclease from neurospora crassa, an enzyme exhibiting both deoxyribo- and ribonuclease activities. no significant differences were observed in total deoxyribonuclease activity between rad+ and rad mutants. the antibody preci ...19882830467
a 3' splice site mutation in a nuclear gene encoding a mitochondrial ribosomal protein in neurospora crassa.we showed previously that the cyt-21+ gene of neurospora crassa encodes a mitochondrial ribosomal protein homologous to escherichia coli ribosomal protein s-16 (kuiper, m. t. r., akins, r. a., holtrop, m., de vries, h., and lambowitz, a. m. (1988) j. biol. chem. 263, 2840-2847). a mutation in this gene, cyt-21-1, results in deficiency of mitochondrial small ribosomal subunits and small rrna (collins, r. a., bertrand, h., lapolla, r. j., and lambowitz, a. m. (1979) mol. gen. genet. 177, 73-84). i ...19882830267
isolation and analysis of the neurospora crassa cyt-21 gene. a nuclear gene encoding a mitochondrial ribosomal protein.the neurospora crassa nuclear mutant cyt-21-1 (originally 297-24; pittenger, t.h., and west, d.j. (1979) genetics 93, 539-555) has a defect leading to gross deficiency of mitochondrial small ribosomal subunits. here, we have cloned the cyt-21+ gene from a n. crassa genomic library, using the sib selection procedure (akins, r. a., and lambowitz, a. m. (1985) mol. cell biol. 5, 2272-2278). the genomic clone contains a short split gene encoding a basic protein of 107 amino acid residues. this prote ...19882830266
Displaying items 4701 - 4800 of 5889