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trans-nuclear action of the nit-2 regulatory gene product and study of two additional nitrogen control genes in neurospora crassa.the nit-2 gene of neurospora crassa is a major regulatory gene for control of nitrogen metabolism. synthesis of the enzyme l-amino acid oxidase requires a functional nit-2 gene product and is also controlled by amino acid induction and nitrogen catabolite repression. electrophoretic variants of l-amino acid oxidase have been employed to demonstrate that in heterokaryons, a nit-2 (+) gene product can turn on the expression of this enzyme in its own nucleus and also in nuclei that possess a nit-2 ...198324173118
the structure of the gene for subunit i of cytochrome c oxidase in neurospora crassa mitochondria.we have sequenced the gene for cytochrome c oxidase subunit 1 (co i) in neurospora crassa mitochondrial dna. the gene is coded by the same strand as the rrna and trna genes. the coding sequence predicts a protein of 557 amino acids, starting with methionine, and ending with asparagine. comparison to the n-terminal amino acid sequence of the mature protein (werner et al. 1980) reveals that the methionine is located at position -2. no other upstream aug codons have been found in frame. the c-termi ...198324173114
repressible extracellular phosphodiesterases showing cyclic 2',3'- and cyclic 3',5'-nucleotide phosphodiesterase activities in neurospora crassa.two molecular species of repressible extracellular phosphodiesterases showing cyclic 2',3'- and cyclic 3',5'-nucleotide phosphodiesterase activities were detected in mycelial culture media of wild-type neurospora crassa and purified. the two molecular species were found to be monomeric and polymeric forms of an enzyme constituted of identical subunits having molecular weights of 50,000. this enzyme had the same electrophoretic mobility as repressible acid phosphatase. the enzyme designated repre ...19836311798
comparison of the cytotoxic and mutagenic effects of selected mutagens on excision repair-sufficient and -deficient ad-3 mutants of neurospora crassa.the excision repair-deficient genetic marker uvs-2 was crossed into the tester strains n23 and n24 of neurospora crassa. comparison was made among the effects of selected mutagens on a repair-sufficient strain (n23 or n24) and a repair-deficient strain (n23 uvs-2 or n24 uvs-2) with regard to cell killing and induction of reverse mutation from adenine dependence to adenine independence. methyl methanesulfonate (mms), ethyl methanesulfonate (ems), 1,2,7,8-diepoxyoctane (deo), n-methyl-n'-nitro-n-n ...19836226873
reconstitution of adenylate cyclase in neurospora from two components of the enzyme.the atp-mg2+-dependent, guanine nucleotide-stimulated adenylate cyclase of neurospora crassa was shown to be composed of distinct components which, when mixed, can reconstitute a holoenzyme. after brief heat treatment, the adenylate cyclase activity in crude homogenates of neurospora was found to have reduced activity and greatly reduced sensitivity to stimulation by guanyl-5'-yl-imidodiphosphate (gpp(nh)p). gpp(nh)p sensitivity could be restored by addition of a homogenate from a crisp-1 (cr-1) ...19836830259
measurements of cytoplasmic and vacuolar ph in neurospora using nitrogen-15 nuclear magnetic resonance spectroscopy.the nitrogen-15 chemical shift of the n1 (tau)-nitrogen of 15n-labeled histidine and the half-height line widths of proton-coupled resonances of the delta- and omega,omega'-nitrogens of 15n-labeled arginine and of the alpha-nitrogens of 15n-labeled alanine and proline were measured in intact mycelia of neurospora crassa to obtain to estimates of intracellular ph. for intracellular 15n-labeled histidine, the n1 (tau)-nitrogen chemical shift was 200.2 ppm. in vitro measurements showed that the che ...19836220738
characterization of an atp-mg2+-dependent guanine nucleotide-stimulated adenylate cyclase from neurospora crassa.a novel adenylate cyclase activity was found in crude homogenates of neurospora crassa. the adenylate cyclase had substantial activity with atp-mg2+ as substrate differing significantly from the strictly atp-mn2+-dependent enzyme characterized previously. additionally, the atp-mg2+-dependent activity was stimulated two- to fourfold by gtp or guanyl-5'-yl-imido-diphosphate (gpp(nh)p). we propose that the atp-mg2+-dependent, guanine nucleotide-stimulated activity is due to a labile regulatory comp ...19836219625
modification of the neurospora crassa plasma membrane [h+]-atpase with n,n'-dicyclohexylcarbodiimide.the [h+]-atpase of the neurospora plasma membrane is composed of a single mr = 104,000 polypeptide (b. j. bowman, f. blasco, and c. w. slayman, j. biol. chem. (1981) 256, 12343-12349). the carboxyl-modifying reagent n,n'-dicyclohexylcarbodiimide (dccd) inactivates the atpase with pseudo-first order kinetics, suggesting that one site on the enzyme is involved. the rate constant for inactivation at ph 7.5 and 30 degrees c is approximately 1000 m-1 min-1, similar to values reported for the dccd-bin ...19836218168
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
re-assessment of ammonium-ion affinities of nadp-specific glutamate dehydrogenases. activation of the neurospora crassa enzyme by ammonium and rubidium ions.the nadp-specific glutamate dehydrogenase of neurospora crassa shows complex interactions with nh4+ ions, characterized by biphasic downwardly convex double-reciprocal plots. these kinetics are explained by the action of nh4+ both as a substrate and, acting at a separate cation-binding site, as an activator. rb+ ions, and to a smaller extent other univalent cations, also activate by acting as analogues of nh4+. previous failure to recognize this effect, which probably also occurs in homologous e ...19836221721
characterization of a 45-kda polypeptide as the precursor of subunit 1 of cytochrome c oxidase in neurospora crassa.in 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
[14c]n-ethylmaleimide labeling of the plasma membrane [h+]-atpase of neurospora crassa.treatment of the purified plasma membrane [h+]-atpase of neurospora crassa with the sulfhydryl reagent n-ethylmaleimide (nem) leads to a marked inhibition of atpase activity. several lines of evidence indicate that inhibition is caused by the reaction of nem with a single cysteine residue on the mr = 104,000 polypeptide. (1) inhibition by nem follows pseudo-first order kinetics. (2) mgadp protects against nem inactivation and at the same time decreases the incorporation of [14c]nem into the mr = ...19836217204
on the presence of a heme-binding domain homologous to cytochrome b(5) in neurospora crassa assimilatory nitrate reductase.assimilatory nitrate reductase has been purified with 55% recovery from a neurospora crassa nmr-1 nit-6 mutant, using a modification of a published procedure. it possesses one heme per 240 000 g, and subunits of mol. wt. 68 000. upon digestion with chymotrypsin, a heme-binding domain was isolated by gel filtration; its visible spectrum was highly similar to that of cytochrome b(5). on sds gels, the fraction showed two heme-containing bands of 10 000 and 12 5000 daltons; their amino acid composit ...198316453480
[purification and isolation of the arom aggregates of schizosaccharomyces pombe].the five enzymes that catalyzing steps two through six in the prechorismate polyaromatic amino acid biosynthetic pathway are physically associated and have been purified up to 400-fold from schizosaccharomyces pombe. the native arom aggregate has a molecular weight of approx. 140,000-145,000 based on gel filtration, glycerol-density-gradient centrifugation, and polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate. similarities between the s. pombe arom aggregate and that ...19836624143
isolation and properties of the porin of the outer mitochondrial membrane from neurospora crassa. 19836318030
biogenesis of cytochrome c in neurospora crassa. 19836318029
ribosomal genes of neurospora crassa: constancy of gene number in the conidial and mycelial phases, and homogeneity in length and restriction enzyme cleavage sites within strains.we report the results of experiments which, while not specifically designed to study the possibility of rdna amplification during different developmental stages in the n. crassa life cycle, clearly indicate a relative constancy in the rdna content of conidia (asexual spores) and mycelial cells. we also report the results of restriction enzyme studies which indicate that the neurospora rdna repeat units are homogeneous in length and restriction site pattern within any given neurospora strain. the ...19836227796
uses of arginaseless cells in the study of polyamine metabolism (neurospora crassa). 19836225934
uptake and dissimilation of glycerol by wild type and glycerol nonutilizing strains of neurospora crassa.seven mutant strains defective for utilization of glycerol, glyceraldehyde or dihydroxyacetone were isolated. one strain was deficient for nad-linked glycerol-3-phosphate dehydrogenase, two for glycerol kinase, and four had no detected enzymatic deficiency, although one of the latter strains was deficient in glycerol uptake. glycerol uptake was increased by incubation in glycerol, glycerol-3-phosphate, erythritol, and propanediol, and was protein-mediated below 0.14 mm glycerol, but at higher co ...19836222238
a study of the properties of pyruvate kinase isolated from a mutant of neurospora crassa: a comparison with the parental enzyme.1. a mutant of neurospora crassa has been isolated whose pyruvate kinase is twice as active as the wild type enzyme. 2. the purified mutant and the wild type enzymes exhibit similar immunological properties, pi values (6.4) and arrhenius activation energy (11.2 kcal/mol). 3. both the enzymes show hyperbolic saturation kinetics with adp and sigmoidal kinetics with pep. 4. the mutant enzyme displays a higher affinity for pep and a greater extent of cooperativity in binding than the wild type. 5. c ...19836221961
photoinduction of protoperithecia in neurospora crassa by blue light. 19836220417
biosynthetic pathway of mitochondrial atpase subunit 9 in neurospora crassa.subunit 9 of mitochondrial atpase (su9) is synthesized in reticulocyte lysates programmed with neurospora poly a-rna, and in a neurospora cell free system as a precursor with a higher apparent molecular weight than the mature protein (mr 16,400 vs. 10,500). the rna which directs the synthesis of su9 precursor is associated with free polysomes. the precursor occurs as a high molecular weight aggregate in the postribosomal supernatant of reticulocyte lysates. transfer in vitro of the precursor int ...19836219116
vanadate-resistant mutants of neurospora crassa are deficient in a high-affinity phosphate transport system.mutant strains of neurospora crassa have been selected which grow on media containing vanadate, an inhibitor of the plasma membrane atpase. the mutations all map to a single region (designated van) on the left arm of linkage group vii. the van mutants are unable to take up vanadate from the medium and are also deficient in the uptake of phosphate via a derepressible, high-affinity phosphate transport system. in the van mutants, the k(m) for phosphate transport is elevated as much as 35-fold, ind ...19836217193
vanadate uptake in neurospora crassa occurs via phosphate transport system ii.vanadate, a potent inhibitor of plasma membrane atpases, is taken up by neurospora crassa only when cells are growing in alkaline medium and starving for phosphate. the appearance of a vanadate uptake system (km = 8.2 microm; vmax = 0.15 mmol/min per liter of cell water) occurs under the same conditions required for derepression of a high-affinity phosphate transport system. phosphate is a competitive inhibitor of vanadate uptake, and vanadate is a competitive inhibitor of phosphate uptake. furt ...19836217192
molecular cloning of middle-abundant mrnas from neurospora crassa. 19836197613
folylpolyglutamate synthetase activities of neurospora crassa: nature of products formed by soluble and particulate enzymes in the wild type and polyglutamate-deficient mutants.the folylpolyglutamate synthetase activities of neurospora crassa wild type (fgsc 853) and two polyglutamate-deficient mutants (met-6, 35809, fgsc 1330 and mac, 65108, fgsc 3609) were examined using dialyzed extracts prepared during exponential mycelial growth. enzyme assay was based on incorporation of [u-3h]glutamate in folylpolyglutamates that were separated by gradient elution from deae-cellulose. extracts of the wild type produced h4pteglu2 (15%), h4pteglu3 (35%) and h4pteglu6 (50%) when an ...19836193684
mutagenesis at the ad-3a and ad-3b loci in haploid uv-sensitive strains of neurospora crassa. vi. genetic characterization of ad-3 mutants provides evidence for qualitative differences in the spectrum of genetic alterations between wild-type and nucleotide excision-repair-deficient strains.genetic characterization of ad-3b mutants induced in wild-type and uv-sensitive strains has revealed qualitative differences between the spectra of genetic alterations at the molecular level. ad-3b mutants induced in the two nucleotide excision-repair-deficient strains upr-1 and uvs-2 (worthy and epler, 1973) had significantly lower frequencies of nonpolarized complementation patterns and higher frequencies of noncomplementing mutants than ad-3b mutants induced in the wild-type strain in samples ...19836188039
transformation of aspergillus nidulans by the orotidine-5'-phosphate decarboxylase gene of neurospora crassa.relief of an auxotrophic requirement for uridine in aspergillus nidulans strain g191 has been achieved by transformation with a segment of neurospora crassa dna containing the corresponding gene coding for orotidine-5'-phosphate decarboxylase. the mitotic stability of such transformants suggests that the dna has integrated into the genome. southern hybridisation analysis of dna isolated from transformants revealed the presence of pbr322 sequences which have integrated into the host genome along ...19836220717
the biosynthesis of brominated pyrrolnitrin derivatives by pseudomonas aureofaciens.the mutant strain acn of pseudomonas aureofaciens atcc 15926 produces several bromo derivatives of pyrrolnitrin. five brominated amino- and three brominated nitrophenyl pyrrole compounds could be isolated, and their structures were established by 1h nmr, uv and mass spectroscopy. the isolated amino compounds showed no biological activity; the nitro derivatives inhibited the growth of neurospora crassa atcc 9276, though not as effective as pyrrolnitrin itself. 2-carboxy-4-(2-amino-3-bromophenyl)p ...19836662814
identification of an iron uptake system specific for coprogen and rhodotorulic acid in escherichia coli k12.with the lac operon fusion technique, mutants were isolated in two genes that specify two outer membrane proteins designated fhue (76 k) and fiu (83 k). the synthesis of both proteins was increased under low iron growth conditions. the fhue-protein was shown to be necessary for iron uptake via coprogen, an iron chelator produced by certain fungi, e.g. neurospora crassa. in addition to fhuee the genes fhucdb, tonb and exbb were necessary for iron coprogen uptake. the gene fhue was mapped between ...19836353165
genetic toxicology of ethylenediaminetetraacetic acid (edta).edta and its salts have a number of applications in medicine and pharmacy. edta is used to remove calcium from the human body, and serves as an anticoagulant and as a detoxicant after poisoning by heavy metals. it is often used in analytical chemistry for complexometric titrations and many other purposes. because the compound is of rather low toxicity, it is used as a food additive to bind metal ions. edta affects the inhibition of dna synthesis in primary cultures of mammalian cells. this may b ...19836406880
distribution of a corticosteroid-binding protein in candida and other fungal genera.using [3h]corticosterone as a probe, corticosteroid-binding protein (cbp) was detected in eight out of eight isolates of candida albicans, of both a and b serotypes. the apparent dissociation constant (kd) in the various isolates ranged between 8 and 19 nm; the binding capacity varied from 122 to over 2400 fmol (mg cytosol protein)-1. there was no correlation between the amount or affinity of cbp and isolate virulence for murine hosts. further analysis revealed demonstrable cbp in six out of six ...19836355389
receptor sites involved in posttranslational transport of apocytochrome c into mitochondria: specificity, affinity, and number of sites.assembly of cytochrome c involves a series of steps: synthesis of apocytochrome c on free ribosomes, specific binding of apocytochrome c to the mitochondrial surface, transfer across the outer membrane, covalent addition of protoheme, refolding of the polypeptide chain, and association of holocytochrome c with its functional sites at the inner membrane. the binding step of apocytochrome c to neurospora crassa mitochondria was studied by inhibiting the subsequent transfer steps with the heme anal ...19836308663
survey, purification, and properties of sugar phosphate phosphohydrolase among microorganisms.sugar phosphate phosphohydrolase was purified approximately 500- to 600-fold to apparent homogeneity from escherichia coli b, escherichia coli c, escherichia coli var. communior, escherichia acidilactici, enterobacter aerogenes, neisseria meningitidis, and saccharomyces cereviseae. the molecular weights of the enzyme as estimated by gel filtration ranged from 97 x 10(3) to 101 x 10(3). the enzyme was composed of two subunits with the same molecular weight which ranged from 50 x 10(3) to 52 x 10( ...19836322944
isolation of dna from filamentous fungi and separation into nuclear, mitochondrial, ribosomal, and plasmid components.a general procedure for purifying and efficiently separating four types of dna from filamentous fungi has been developed. the protocol involves (i) disruption of mycelial cells by blending in liquid nitrogen followed by suspension of cell contents in buffer containing high concentrations of protease and edta; (ii) deproteinization with phenol; (iii) cesium chloride/bisbenzimide density gradient centrifugation to separate nuclear dna, mitochondrial dna, and ribosomal dna; and (iv) agarose gel ele ...19836318603
purification and properties of single strand dna-binding endo-exonuclease of neurospora crassa.single strand dna-binding endo-exonucleases purified from mitochondria, vacuoles, or a mixture of these organelles had the same high specific single strand dnase activity (910 mumol of nucleotides/min/mg), and each contained a polypeptide of mr = 31,000-33,000 which was found to be active by sodium dodecyl sulfate-dna-gel electrophoresis. the properties of the three preparations were identical in all respects tested. the enzyme showed distributive endonuclease activity with single strand dna, bu ...19836311833
cytochrome oxidase subunit 2 gene in neurospora crassa mitochondria.the nucleotide sequence of the cytochrome oxidase subunit 2 (cox2) gene has been obtained from cloned mitochondrial dna segments of neurospora crassa. the coding sequences have been identified on the basis of protein sequence homology with the subunit 2 of cytochrome oxidase from yeast and man. the postulated precursor of the n. crassa subunit 2 protein is 250 amino acids long, with a molecular weight of 28,700. as in the trna and rrna genes, the subunit 2 gene is flanked by g + c-rich palindrom ...19836313689
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
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
molybdenum cofactor in chlorate-resistant and nitrate reductase-deficient insertion mutants of escherichia coli.we examined molybdenum cofactor activity in chlorate-resistant (chl) and nitrate reductase-deficient (nar) insertion mutants and wild-type strains of escherichia coli k-12. the bacterial molybdenum cofactor was assayed by its ability to restore activity to the cofactor-deficient nitrate reductase found in the nit-1 strain of neurospora crassa. in the wild-type e. coli strains, molybdenum cofactor was synthesized constitutively and found in both cytoplasmic and membrane fractions. cofactor was fo ...19836307982
cloning of the structural gene for orotidine 5'-phosphate carboxylase of neurospora crassa by expression in escherichia coli.a neurospora gene bank in plasmid prk9 was used to complement pyrimidine auxotrophs in e. coli. two plasmids were obtained that complement a pyrf mutant of e. coli. these plasmids hybridise to neurospora dna and transform a pyr-4 strain of neurospora. the promoter used in expressing the orotidine 5'-monophosphate carboxylase in e. coli is within the neurospora sequence.19836308396
complete nucleotide sequence of the escherichia coli gdha gene.the dna sequence of the gdha gene of escherichia coli k12, which encodes the 447 amino acid polypeptide subunit of nadp-specific glutamate dehydrogenase, is presented. the deduced protein sequence is strongly homologous to the corresponding enzyme of the eukaryotic fungus neurospora crassa. the upstream dna sequence includes several overlapping promoter consensus sequences. the downstream dna sequence contains inverted repeats, predicted as forming long stable stem-loop structures in rna, homolo ...19836308576
the genes coding for histone h3 and h4 in neurospora crassa are unique and contain intervening sequences.sequences coding for histone h3 and h4 of neurospora crassa could be identified in genomic digests with the use of the corresponding genes from sea urchin and x. laevis as hybridization probes. a 2.6 kb hindiii-generated n. crassa dna fragment, showing homology with the heterologous histone h3-gene probes was cloned in a charon 21a vector. using dna from this clone as a homologous hybridization probe a 6.9 kb sali-generated dna fragment was isolated which in addition to the histone h3-gene also ...19836310494
isolation of complex iii from various mitochondria. comparison of the structural and functional properties of the preparations from beef heart, calf liver and neurospora crassa.active complex iii was isolated by an improved procedure from beef heart mitochondria, from neurospora crassa mitochondria and for the first time from mitochondria originating from mammalian tissue other than heart, i.e. calf liver. the described procedure consists of differential extraction of the respective mitochondria, hydroxyapatite chromatography and, finally, either gel- or affinity chromatography. the preparations contain the well known prosthetic groups, i.e. 6-8 mumol b-type heme, 3-4 ...19836321316
mutagenicity screening with fungal systems.several fungal species have been used for mutagenicity screening: aspergillus nidulans, saccharomyces cerevisiae, and neurospora crassa. the eukaryotic nature of these organisms with typical chromosomes in a nucleus and their mitotic and meiotic mode of nuclear division have been the basis for the development of test systems that cover the full spectrum of genetic changes typical for eukaryotes. it is possible to detect simple point mutations and also grosser structural chromosomal alterations. ...19836349475
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
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
a colony filter-hybridization procedure for the filamentous fungus neurospora crassa.a colony filter-hybridization procedure for the filamentous fungus neurospora crassa has been developed. the procedure is sensitive enough to detect escherichia coli plasmid pbr322 dna integrated into chromosomal dna in a neurospora transformant. thus, it should facilitate the isolation of nuclear genes by plasmid-rescue procedures.19836229196
radioassay of the folate-hydrolyzing enzyme activity, and the distribution of the enzyme in biological cells and tissues.a sensitive radioassay method has been developed to quantitate the activity of the folate-hydrolyzing enzyme which catalyzes the hydrolysis of folic acid to pteroic acid and glutamic acid. the method is based on analyzing [2-14c]pteroic acid separated by a thin-layer chromatography on an avicel sf cellulose plate using 0.1 m potassium phosphate buffer, ph 7.0, as a solvent. this method was found to be more sensitive than a conventional photometric method to determine the activity of the folate-h ...19836229614
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
purification and characterization of an extracellular acid protease from neurospora crassa.an extracellular acid protease was purified 1420-fold from sulfur-starved protein-induced cultures of neurospora crassa. the enzyme was homogeneous as determined by polyacrylamide electrophoresis. the purification procedure consisted of an ultrafiltration step, cation-exchange chromatography, and affinity chromatography on sepharose-linked pepstatin. the enzyme is homologous to aspartyl proteases that are characterized by pepstatin inhibition and trypsinogen activation. it is extremely autolytic ...19836222698
the complete nucleotide sequence of the neurospora crassa am (nadp-specific glutamate dehydrogenase) gene.the complete nucleotide sequence of a 2.7-kb genomic fragment, containing the neurospora crassa am [nadp-specific glutamate dehydrogenase (gdh)] gene, has been determined. the transcription initiation and polyadenylation sites have been defined by s1 mapping. there are at least four initiation sites between 35 and 60 bases downstream of a tataaa sequence. the single polyadenylation site is immediately downstream of a six-nucleotide sequence which is present in the corresponding position in the n ...19836231215
a chicken repetitive dna sequence that is highly sensitive to single-strand specific endonucleases.a dna sequence consisting of the 5-mer agagg repeated tandemly 32 times has been detected in a chicken genomic clone and found to be present in about 2000 copies per chicken genome. this sequence was highly susceptible to single-strand specific endonucleases isolated from aspergillus oryzae (s1) and mung bean, but cleavage by a single-strand specific endonuclease isolated from neurospora crassa occurred only at a ph below 5.5. endonucleolytic cutting of the agagg sequence by the single-strand sp ...19836231528
biosynthesis and assembly of nuclear-coded mitochondrial membrane proteins in neurospora crassa. 19836228709
molecular dosimetry of the chemical mutagen ethyl methanesulfonate. quantitative comparison of the mutagenic potency in neurospora crassa and saccharomyces cerevisiae.extending previous work with e. coli and mammalian cells in culture, forward-mutation frequencies induced by ethyl methanesulfonate (ems) were quantitatively compared in neurospora crassa and saccharomyces cerevisiae under standardized conditions. concomitantly, the actual dose to dna was measured by determining the amount of radioactivity bound to dna after treatment with tritium-labeled ems. after exposure to ems (2.5-50 mm), alkylation levels in n. crassa and s. cerevisiae were similar to tho ...19836218404
peptide utilization by nitrogen-starved neurospora crassa.peptides ranging in size from a mean number of 30 residues down to dipeptides supported growth of a leucine auxotroph when used as both a nitrogen and leucine source. under nitrogen-limiting conditions, the peptides induced extracellular peptidohydrolytic activity, hydrolyzing peptides to monomer amino acids. growth of a leu-2 mutant of neurospora crassa on those peptides transportable by the oligopeptide transport system did not result in induction of hydrolytic activity, whereas growth of a le ...19836219099
structure of the trifunctional trp-1 gene from neurospora crassa and its aberrant expression in escherichia coli.the trifunctional trp-1 gene from neurospora crassa was cloned by complementation of a phosphoribosylanthranilate isomerase-deficient mutant of e. coli. a 2.7-kb dna sequence containing trp-1 was determined. homology of the deduced trp-1 polypeptide sequence to the corresponding e. coli proteins is striking; the order of functional domains within trp-1 is nh2-glutamine amidotransferase-indoleglycerolphosphate synthase-phosphoribosylanthranilate isomerase-cooh (nh2-trpg-trpc-trpf-cooh). whereas t ...19836221060
control of the ornithine cycle in neurospora crassa by the mitochondrial membrane.in neurospora crassa, the mitochondrial membrane separates ornithine used in arginine biosynthesis from ornithine used in the arginine degradative pathway in the cytosol. ornithine easily exchanges across the mitochondrial membrane under conditions appropriate for synthesis of the immediate biosynthetic product, citrulline. neither of the two mitochondrial enzymes required for the ornithine-to-citrulline conversion is feedback inhibitable in vitro. nevertheless, when arginine is added to cells a ...19836222031
ribosomal rna genes of neurospora crassa: multiple copies and specificities.ribosomal rna genes were isolated from the germinated conidial and mycelial cells of n. crassa by repeated cycles of 3h-dna:rrna reactions followed by hydroxyapatite chromatography. specificity of multiple copies of those rdnas with respect to n. crassa cell types was studied. the fraction of n. crassa germinated conidial in vitro labelled 3h-dna recovered in the presence of rrna isolated from the same cell type was about 2.2%, when compared with approximately 1.2% rdnas obtained in mycelial cel ...19836222241
[microbiological short-time tests for the evaluation of mutagenic potential of chemical substances].during the last 20 years it became much more interesting to test new chemicals as fast as possible for their carcinogenic potency. therefore new test models were developed. mutagenicity seems to be one sign for carcinogenicity. therefore test systems using microorganisms were studied which are influenced by mutagenic substances. these systems are described, first of all the ames-test, using revertants of salmonella typhimurium, secondly the escherichia coli system deficient of dna-polymerase a ( ...19836222262
evolutionary aspects of accuracy of phenylalanyl-trna synthetase. a comparative study with enzymes from escherichia coli, saccharomyces cerevisiae, neurospora crassa, and turkey liver using phenylalanine analogues.the phenylalanyl-trna synthetases from escherichia coli, saccharomyces cerevisiae, neurospora crassa, and turkey liver activate a number of phenylalanine analogues (tyrosine, leucine, methionine, p-fluorophenylalanine, beta-phenylserine, beta-thien-2-ylalanine, 2-amino-4-methylhex-4-enoic acid, mimosine, n-benzyl-l- or n-benzyl-d-phenylalanine, and ochratoxin a), as demonstrated by km and kcat of the atp/ppi pyrophosphate exchange. upon complexation with trna, the enzyme-trnaphe complexes show a ...19836222761
a study of the heat-shock response in neurospora crassa.1. neurospora crassa was grown at 28 degrees c for 12 hr and transferred to higher temperatures for 2 hr. 2. cultures labelled with [35s]methionine showed the synthesis of several new proteins in response to heat-shock at 46 to 48 degrees c. 3. major polypeptides of approximate mr 105,000, 99,000, 78,000, 43,000 and 23,000 were detectable in one-dimensional sds-polyacrylamide slab gel electropherograms. 4. 2-d analysis using isoelectric-focussing in the first dimension and electrophoresis in sds ...19836222926
[isolation and characteristics of the nucleosomes from the mold neurospora crassa]. 19836227467
nucleotide sequence and intron structure of the apocytochrome b gene of neurospora crassa mitochondria.the sequence of the apocytochrome b (cob) gene of neurospora crassa has been determined. the structural gene is interrupted by two intervening sequences of approximately 1260 bp each. the polypeptide encoded by the exons shows extensive homology with the cob proteins of aspergillus nidulans and saccharomyces cerevisiae (79% and 60%, respectively). the two introns are, however, located at sites different from those of introns in the cob genes of a. nidulans and s. cerevisiae (which contain highly ...198310872314
cytochrome b gene of neurospora crassa mitochondria. partial sequence and location of introns at sites different from those in saccharomyces cerevisiae and aspergillus nidulans.we have sequenced a 2614-base pair fragment of the neurospora crassa mitochondrial dna which contains part of the structural gene for apocytochrome b. this gene is split by at least two introns. the sequence reported here begins within one intron, extends through the next exon, another intron 1276 base pairs long, and the last exon which encodes the cooh terminus of cytochrome b. within the 254 amino acids encoded by the two exons, there is a high degree of sequence conservation, 81%, with cytoc ...19846231283
ultrastructural aspects of cytoplasmic ribosomes from histoplasma capsulatum and blastomyces dermatitidis as revealed by heavy metal staining.cytoplasmic ribosomes were isolated and purified from sonicates of the mycelial and yeastlike growth forms of the pathogenic dimorphic fungi, histoplasma capsulatum and blastomyces dermatitidis. similar ribosomal fractions were prepared from neurospora crassa and saccharomyces cerevisiae. these latter organisms were selected as typical filamentous and yeastlike monophasic fungi, and their ribosomes were used as reference standards. high resolution electron microscopy permitted a comparison of bo ...19846206396
inhibition of superoxide dismutase by nitroprusside and electron spin resonance observations on the formation of a superoxide-mediated nitroprusside nitroxyl free radical.nitroprusside appears to inhibit the known types of superoxide dismutases irrespective of their metal prosthetic group and regardless of the source from which the enzymes were isolated. thus the copper-zinc enzyme from bovine erythrocyte or neurospora crassa behaved identically as did the manganese enzymes from escherichia coli or red alga and the iron enzyme from e. coli and a blue-green alga. the inhibition was dose dependent with a ki = 2.5 x 10(-5) for nitroprusside. nitroprusside does not b ...19846092342
preparative-scale isolation and purification of procaryotic and eucaryotic ribosomal 5 s rna: bacillus subtilis, neurospora crassa, and wheat germ.ribosomal 5 s rna from three different organisms has been isolated in high yield and purity. without prior isolation of ribosomes, a presoak in buffer followed by phenol extraction, de-32 ion-exchange chromatography, and sephadex g-75 gel-permeation chromatography yields at least 5-10 mg of electrophoretically homogeneous 5 s rna from 100 g of cells. ribonuclease activity is eliminated by various combinations of low temperature, sodium dodecyl sulfate, phenol, and bentonite. high-molecular-weigh ...19846204554
the mitochondrial genome of the fission yeast schizosaccharomyces pombe. 2. localization of genes by interspecific hybridization in strain ade7-50h- and cloning of the genome in small fragments.a series of 18 small overlapping restriction fragments has been cloned, covering the complete mitochondrial genome of schizosaccharomyces pombe. by hybridizing mitochondrial gene probes from saccharomyces cerevisiae and neurospora crassa with restriction fragments of schizosaccharomyces pombe mitochondrial dna, the following homologous genes were localized on the mitochondrial genome of s. pombe: cob, cox1, cox2 and cox3, atpase subunit 6 and 9 genes, the large rrna gene and both types of open r ...19846094974
transformation of neurospora crassa with recombinant plasmids containing the cloned glutamate dehydrogenase (am) gene: evidence for autonomous replication of the transforming plasmid.we have characterized neurospora crassa transformants obtained with plasmid pjr2, which consists of the neurospora glutamate dehydrogenase (am) gene cloned in puc8 and an am132 host strain which contains a deletion encompassing the cloned fragment. every one of 33 transformants tested showed extreme meiotic instability: less than 1 or 2% am+ progeny were obtained in initial or successive backcrosses between am+ transformants and am132 or in intercrosses between am+ progeny. furthermore, am+ prog ...19846095037
the relationship of mo, molybdopterin, and the cyanolyzable sulfur in the mo cofactor.reconstitution of the apoprotein of the molybdoenzyme nitrate reductase in extracts of the neurospora crassa mutant nit-1 with molybdenum cofactor released by denaturation of purified molybdoenzymes is efficient in the absence of exogenous moo2-4 under defined conditions. evidence is presented that this molybdate-independent reconstitution is due to transfer of intact mo cofactor, a complex of mo and molybdopterin (mpt), the organic constituent of the cofactor. this complex can be separated from ...19846231887
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
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
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
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
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
acidic ribosomal proteins of neurospora crassa.neurospora crassa acidic ribosomal proteins from the high salt-ethanol extract of 80 s ribosomes have been fractionated by deae-cellulose chromatography. six acidic ribosomal proteins were purified. all resemble escherichia coli l7 and l12 in amino acid composition and molecular weight but each has a slightly different net charge at ph 3.2. four have an apparent molecular weight of approx. 14 000, and two have a molecular weight of approx. 14 800. the amino acid compositions and circular dichroi ...19846231958
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
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
isolation and characterization of mms-sensitive mutants of neurospora crassa.seven different mutants that show high sensitivity to mms killing were isolated and mapped at different loci. one group, mms-(sa1), mms-(sa2) and mms-(sa6), showed high sensitivity to mms but not to uv or gamma-rays. another group, mms-(sa4) and mms-(sa5), showed extremely high sensitivity to uv and mms. and mms-(sa3) and mms-(sa7) were moderately sensitive to both uv and mms. mms-(sa4) and mms-(sa1) were identified as alleles of uvs-2 and mus-7, respectively, which had been previously isolated. ...19846230534
mutation tests in neurospora crassa. a report of the u.s. environmental protection agency gene-tox program.many mutation tests have been developed in neurospora crassa during the almost 40 years of its use in mutation research. these tests detect two major classes of mutation: gene mutation and meiotic nondisjunction. within the first class, forward- and reverse-mutation tests have been used. the forward-mutation tests include those that detect mutations at many loci and at specific loci. both kinds of forward-mutation tests have been done in homokaryons (n) and heterokaryons (n + n'). from the publi ...19846231482
activation of nit-1 nitrate reductase by w-formate dehydrogenase.formate dehydrogenase ( fdh ) from clostridium thermoaceticum is a known tungsten enzyme. fdh was tested for the presence of nitrogenase-type cofactor and nitrate reductase-type cofactor by the azotobacter vinelandii uw-45 and neurospora crassa nit-1 reconstitution assays, respectively. tungsten formate dehydrogenase (w- fdh ), containing only a small mo impurity, activated the nit-1 nitrate reductase extracts when molybdate was also added, but not when tungstate was added. these results show w- ...19846234890
evidence for two control genes regulating expression of the quinic acid utilization (qut) gene cluster in aspergillus nidulans.the first three steps in quinic acid degradation in aspergillus nidulans are catalysed by highly inducible enzymes encoded by a gene cluster regulated by an adjacent control region. analysis of two non-inducible mutants has been done in diploid strains, where quta8 is recessive and all three enzyme activities are fully induced in heterozygous quta8/quta+ diploids. in contrast, quta4/quta+ heterozygous diploids show semi-dominance of the mutant allele, giving markedly diminished growth on quinic ...19846374025
genetically determined conidial longevity is positively correlated with superoxide dismutase, catalase, glutathione peroxidase, cytochrome c peroxidase, and ascorbate free radical reductase activities in neurospora crassa.aging of post-mitotic cells, the conidia, of neurospora crassa is defined as the time-dependent loss of viability under a constant laboratory environment which probably resembles the organism's tropical habitat; namely, at 30 degrees c, 85-100% relative humidity under white light. median lifespan is defined as the age at which survival of a conidial population has declined to 50% of that of a fully viable population at birth. a collection of short (age-) and long-lived (age+) mutants were previo ...19846319835
nucleotide sequence of saccharomyces cerevisiae genes trp2 and trp3 encoding bifunctional anthranilate synthase: indole-3-glycerol phosphate synthase.saccharomyces cerevisiae anthranilate synthase:indole-3-glycerol phosphate synthase is a multifunctional hetero-oligomeric enzyme encoded by genes trp2 and trp3. trp2, encoding anthranilate synthase component i, was cloned by complementation of a yeast trp2 mutant. the nucleotide sequence of trp2 as well as that of trp3 were determined. the deduced anthranilate synthase component i primary structure from yeast exhibits only limited similarity to that of the corresponding escherichia coli subunit ...19846323449
dna polymerases, deoxyribonucleases, and recombination during meiosis in saccharomyces cerevisiae.we utilized strains of saccharomyces cerevisiae that exhibit high efficiency of synchrony of meiosis to examine several aspects of meiosis including sporulation, recombination, dna synthesis, dna polymerase i and ii, and mg2+-dependent alkaline dnases. the kinetics of commitment to intragenic recombination and sporulation are similar. the synthesis of dna, as measured directly with diphenylamine, appears to precede the commitment to recombination. both dna polymerase i and ii activities and tota ...19846396507
isolation and manipulation of genes coding for energy-transducing enzymes from neurospora crassa and escherichia coli. 19846327431
on the origin of chromosomal aberrations in human peripheral lymphocytes in vitro. i. experiments with neurospora endonuclease and polyethylene glycol.post-treatment of mutagen-treated human peripheral lymphocytes with a single-strand specific endonuclease from neurospora crassa leads to a significant elevation of the rate of structural chromosomal aberrations. our results indicate that dna double-strand breaks (dsb) are ultimate lesions for the formation of chromosomal aberrations in the g1 and g2 phase of the cell cycle and probably also in the s-phase. post-treatment of x-irradiated g2 cells with polyethylene glycol (peg) leads to an elevat ...19846327498
the nuclear-coded subunits of yeast cytochrome c oxidase. iii. identification of homologous subunits in yeast, bovine heart, and neurospora crassa cytochrome c oxidases.sequences for the nh2-terminal halves of subunits iv, v, vi, vii, and viia from yeast cytochrome c oxidase have been determined and used to identify homologous subunits in bovine heart and neurospora crassa cytochrome c oxidases. in conjunction with the complete sequence of subunit viii (s. d. power, m. a. lochrie , t. e. patterson, and r. o. poyton (1984) j. biol. chem. 259, 6571-6574), we have been able to identify counterparts to yeast subunits iv, v, vi, and viii in bovine heart cytochrome c ...19846327686
transhyphal electrical currents in fungi.representative mycelial fungi from the phycomycete, ascomycete and basidiomycete groups (achlya bisexualis, neurospora crassa, aspergillus nidulans, schizophyllum commune and coprinus cinereus) all generated steady electrical currents around their hyphal tips; the generation of a transhyphal ion current may therefore be a universal characteristic of hyphal growth. as with all other tip growing organisms, positive current always entered apically and left distally; non-growing hyphae did not drive ...19846520604
molybdopterin in carbon monoxide oxidase from carboxydotrophic bacteria.the carbon monoxide oxidases (coxs) purified from the carboxydotrophic bacteria pseudomonas carboxydohydrogena and pseudomonas carboxydoflava were found to be molybdenum hydroxylases, identical in cofactor composition and spectral properties to the recently characterized enzyme from pseudomonas carboxydovorans (o. meyer, j. biol. chem. 257:1333-1341, 1982). all three enzymes exhibited a cofactor composition of two flavin adenine dinucleotides, two molybdenums, eight irons and eight labile sulfid ...19846582059
analysis of the structure and transcription of the aro3 cluster gene in schizosaccharomyces pombe.by selecting activities to complement escherichia coli aro mutations, a gene responsible for the biosynthesis of aromatic amino acids in schizosaccharomyces pombe (aro3) was cloned into pbr322. three independent clones named pfna1, pfna2 and pfna3 were obtained. pfna1 could complement e. coli arod only, whereas the other two plasmids were able to complement both arod and aroe. the aro3 locus of s. pombe was found to be a gene cluster which can be subdivided into five complons, a through e (strau ...19846092844
interactions between avian myeloblastosis reverse transcriptase and trnatrp. mapping of complexed trna with chemicals and nucleases.the interactions between beef trnatrp with avian myeloblastosis reverse transcriptase have been studied by statistical chemical modifications of phosphate (ethylnitrosourea) and cytidine (dimethyl sulfate) residues, as well as by digestion of complexed trna by cobra venom nuclease and neurospora crassa endonuclease. results with nucleases and chemicals show that reverse transcriptase interacts preferentially with the d arm, the anticodon stem and the t psi stem. all these regions are located in ...19846200830
a mitochondrial reading frame which may code for a second form of atpase subunit 9 in aspergillus nidulans.the nucleotide sequence of a 74 codon reading frame from the aspergillus nidulans mitochondrial genome is presented. the derived amino acid sequence displays typical features of dicyclohexylcarbodiimide (dccd) binding proteins and is 84% homologous with a mitochondrial reading frame that potentially encodes an atpase subunit 9 polypeptide in neurospora crassa. however, in a. nidulans, as in n. crassa, there is strong biochemical and genetic evidence that this subunit is in fact nuclearly-encoded ...198424177948
biogenesis of cytochrome c in neurospora crassa. synthesis of apocytochrome c, transfer to mitochondria and conversion to holocytochrome c.1. precipitating antibodies specific for apocytochrome c and holocytochrome c, respectively, were employed to study synthesis and intracellular transport of cytochrome c in neurospora in vitro. 2. apocytochrome c as well as holocytochrome c were found to be synthesized in a cell-free homogenate. a precursor product relationship between the two components is suggested by kinetic experiments. 3. apocytochrome c synthesized in vitro was found in the post-ribosomal fraction and not in the mitochondr ...1984215405
cloning and preliminary characterization of a molybdenum cofactor gene of neurospora crassa.a neurospora crassa library, constructed in a derivative of the plasmid pbr322 (prk9), was used to transform two e. coli ch1d molybdenum cofactor mutants (ch1d, ch1d::mu). subsequently, one transformant from each of three independent transformation experiments was restriction mapped. all three transformants had an identical n. crassa dna insert (4.2 kb). southern blot analysis with one of the plasmids (pmoco, 1:4) showed hybridization to a single band of n. crassa genomic dna. when pmoco plasmid ...198424177998
biochemical characterization of the molybdenum cofactor mutants of neurospora crassa: in vivo and in vitro reconstitution of nadph-nitrate reductase activity.molybdenum cofactor (moco) mutants of neurospora crassa lack both nadph-nitrate reductase and xanthine dehydrogenase activity. in vivo and in vitro studies to further characterize these mutants are now reported. the moco mutants nit-9a and nit-9b are capable of growing, albeit poorly, with nitrate as the sole nitrogen source, provided high levels of molybdate are present. the moco mutants nit-9a, nit-9b and nit-9c, but not nit-1, nit-7 or nit-8, have significant levels of nadph-nitrate reductase ...198424177997
structure and function of the trp3 gene of saccharomyces cerevisiae: analysis of transcription, promoter sequence, and sequence coding for a glutamine amidotransferase.the structure and function of the trp3 gene of saccharomyces cerevisiae were analyzed. subcloning of an original 4.8 kb bamhi dna fragment, carrying the yeast trp3 gene, allowed for a localization of the gene on a 2.5 kb clai/bamhi fragment. transcription was found to proceed from the clai site towards the bamhi site. three major transcription start sites were determined at positions -92, -87, and -81 by s1-mapping. the synthesis of the trp3 gene is regulated by the general control, and was foun ...198424177735
regulation of a neurospora crassa extracellular rnase by phosphorus, nitrogen, and carbon derepressions.a new extracellular rnase, designated n4, was detected in culture filtrates from neurospora crassa and its regulation was studied. limitation of a nutrient obtainable from rna alone was not sufficient to cause enzyme derepression. the addition of rna to the medium had no inductive effect, but the addition of exogenous protein caused enzyme production. with protein in the medium, n4 was derepressible for all three elemental nutrients obtainable from rna: carbon, nitrogen, and phosphorus. successf ...19846229529
characterization and comparison of a neurospora crassa rnase purified from cultures undergoing each of three different states of derepression.extracellular rnase n4 from neurospora crassa is derepressible by limitation of any of the three nutrient elements obtainable from rna. we have purified and characterized the enzyme from cultures grown under each of the three states of derepression. the purification procedure consisted of an ultrafiltration step, cation-exchange chromatography, and gel filtration. we found only one enzyme (n4) that hydrolyzed rna at ph 7.5 in the presence of edta in culture filtrates from nitrogen-, phosphorus-, ...19846229528
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