TitleAbstractYear(sorted descending)
over-expression, purification and determination of the proteolytic processing site of the yeast mitochondrial cbs1 protein.yeast transformants harboring the cbs1 gene under the control of the strong adc1 promoter on a high copy number plasmid express the mitochondrial cbs1 protein at artificially high levels. over-expressed protein is imported into mitochondria and correctly processed to yield the mature mitochondrial 23.5 kda form, but differs in its solubility properties from cbs1 in wild-type mitochondria. it forms insoluble protein aggregates, which are refractory to solubilization with 1% taurodeoxycholate. we ...19911657414
ubiquitination of endogenous calmodulin in rabbit tissue extracts.previously we were able to show that purified calmodulins from vertebrates, plants (spinach) and the mold neurospora crassa can be covalently conjugated to ubiquitin in a ca(2+)-dependent manner. it was therefore pertinent to answer the question if a tissue extract contains all the components necessary for the endogenous synthesis of ubiquityl calmodulin (ucam). therefore [125i]ubiquitin, atp/mg2+ and ca2+ were added to tissue extracts enriched by a single ion exchange step. in such extracts of ...19911661685
isolation and characterization of the adenylate cyclase structural gene of neurospora crassa.a single gene (nac) encoding an adenylate cyclase was cloned from the genomic dna library of neurospora crassa, using the dna fragment encoding the catalytic domain of adenylate cyclase of saccharomyces cerevisiae as a probe. the open reading frame of this gene (6900 base pairs) was interrupted three time by introns. the protein encoded consists of 2300 amino acids and has adenylate cyclase activity. n. crassa adenylate cyclase has a high degree of homology with the catalytic domains of yeast an ...19911680356
genomic analysis of a virulent and a less virulent strain of the entomopathogenic fungus beauveria bassiana, using restriction fragment length polymorphisms.the genomic dna of two strains of the entomopathogenic fungus beauveria bassiana, strain gk2016, a "wild type" (virulent), and strain gk2051, a less virulent mutant to grasshoppers, was digested with 12 restriction endonucleases. gel electrophoresis conditions were established to show restriction fragment length patterns visually in the digested dna stained with ethidium bromide. the less virulent mutant was generated by ultraviolet illumination of conidiospores at a 95% lethal dose. both strain ...19911680543
isolation and expression of the acetate-inducible isocitrate lyase gene (acu-3) from neurospora crassa: evidence for a second constitutive isozyme.heterologous hybridisation of the aspergillus nidulans structural gene for isocitrate lyase (acud) to a lambda genomic library of neurospora crassa identified a recombinant phage containing the hybridising sequence on an internal 9 kb ecori fragment. a restriction fragment length polymorphism (rflp) enabled the fragment to be assigned to linkage group v (lg v), the location of the acetate-inducible isocitrate lyase, acu-3 of neurospora. functional ectopic complementation by co-transformation of ...19911681413
sequence and expression of gln3, a positive nitrogen regulatory gene of saccharomyces cerevisiae encoding a protein with a putative zinc finger dna-binding domain.the gln3 gene of saccharomyces cerevisiae is required for the activation of transcription of a number of genes in response to the replacement of glutamine by glutamate as source of nitrogen. we cloned the gln3 gene and constructed null alleles by gene disruption. gln3 is not essential for growth, but increased copies of gln3 lead to a drastic decrease in growth rate. the complete nucleotide sequence of the gln3 gene was determined, revealing one open reading frame encoding a polypeptide of 730 a ...19911682800
integrative transformation of the ascomycete podospora anserina: identification of the mating-type locus on chromosome vii of electrophoretically separated chromosomes.protoplasts of wild-type strain s and a long-lived extrachromosomal mutant (al2) of the ascomycete podospora anserina were transformed using a plasmid (pan7-1) which contains the hygromycin b phosphotransferase gene (hph) of escherichia coli under the control of aspergillus nidulans regulatory sequences. after optimizing the transformation procedure, transformation efficiencies of 15-21 transformants/micrograms plasmid dna were obtained. using a second selectable vector (pbt3), which contains th ...19911367277
purification and characterization of chorismate synthase from euglena gracilis: comparison with chorismate synthases of plant and microbial origin.chorismate synthase was purified 1200-fold from euglena gracilis. the molecular mass of the native enzyme is in the range of 110 to 138 kilodaltons as judged by gel filtration. the molecular mass of the subunit was determined to be 41.7 kilodaltons by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. purified chorismate synthase is associated with an nadph-dependent flavin mononucleotide reductase that provides in vivo the reduced flavin necessary for catalytic activity. in vitro, flavi ...199116668543
genetic transformation of the biocontrol fungus gliocladium virens to benomyl resistance.methodology was developed to isolate and regenerate protoplasts from the biocontrol fungus gliocladium virens and to transform them to benomyl resistance with a neurospora crassa beta-tubulin gene. southern blots demonstrated that multiple copies of the vector integrated into the chromosomal dna of stable biotypes but not of abortive transformants. analysis of nuclear condition in vegetative and asexual structures demonstrated that no structure of g. virens is dependably uninucleate and thus pre ...199016348312
occurrence of nitrate reductase and molybdopterin in xanthomonas maltophilia.fifteen of 23 atcc strains and 2 of 9 clinical isolates of xanthomonas maltophilia, all of which grew aerobically on ammonia, but not nitrate, as a sole nitrogen source, reduced nitrate to nitrite. x. maltophilia failed to grow anaerobically on complex medium with or without nitrate, so it is considered an obligate aerobe. nitrate-reducing strains contained reduced methyl viologen nitrate reductase (mvh-nr) with specific activities ranging from 49.2 to 192 u mg of protein. strain atcc 17666 doub ...199016348378
dna-mediated genetic changes in neurospora crassa.evidence for genetic transformation in neurospora crassa is based on the observations that allo-dna has a specific effect in producing transformants which is abolished by dnaase treatment and that iso-dna is not effective in transformation. here, unambiguous evidence for genetic transformation is provided by transfer of a temperature-sensitive inositol requirement from a donor to a recipient strain. data provided also suggest the role of growth conditions and the involvement of a nuclease gene i ...1990159941
cloning of the pyr4 gene encoding orotidine-5'-phosphate decarboxylase in cephalosporium acremonium.we have cloned the cephalosporium acremonium pyr4 gene by cross-hybridization with the equivalent gene from neurospora crassa, the closest relative from which this gene is available. the c. acremonium pyr4 gene complements an e. coli pyrf mutant lacking orotidine-5'-phosphate decarboxylase (ompdecase), and most probably does not contain introns. maxicell analysis in e. coli shows that it encodes a 46 kda polypeptide. the c. acremonium ompdecase contains a highly conserved pentadecapeptide charac ...19902140299
wheat germ agglutinin in wheat seedling roots: induction by elicitors and fungi.treatment of wheat (triticum aestivum l.) seedlings with elicitors originating from either plant or fungal cell walls induces about a 2-fold increase of wheat germ agglutinin (wga) in the roots. while the wga content in roots of healthy plants normally decreases as a function of germination time, a transient accumulation of wga could be observed in plants challenged with different fungi, including rhizoctonia solani, fusarium culmorum, pythium ultimum and neurospora crassa. peak levels in challe ...199024226823
cloning and heterologous expression of the penicillin biosynthetic gene cluster from penicillum chrysogenum.a cosmid clone containing the putative penicillin biosynthetic gene cluster from penicillium chrysogenum was used to transform the related filamentous fungi neurospora crassa and aspergillus niger, which do not produce beta-lactam antibiotics. both of the transformed hosts contained intact p. chrysogenum dna derived from the cosmid clone and produced authentic penicillin v. assays of penicillin biosynthetic enzyme activity additionally demonstrated that they possessed delta-(l-alpha-amino-adipyl ...19901368505
isolation and sequence of an fk506-binding protein from n. crassa which catalyses protein folding.slow protein-folding reactions are accelerated by a prolyl cis/trans isomerase isolated from porcine kidney which is identical to cyclophilin, a protein that is probably the cellular receptor for the immunosuppressant cyclosporin a. catalysis probably involves the isomerization of prolyl peptide bonds in the folding protein chains. cyclosporin a inhibits folding catalysis by cyclophilin. here we report the isolation, cloning, sequencing and expression of another protein with prolyl isomerase act ...19901696687
optimized vectors and selection for transformation of neurospora crassa and aspergillus nidulans to bleomycin and phleomycin provide a dominant selectable marker for transformation of neurospora crassa strains lacking specific auxotrophic mutations, we have engineered the bleomycin (bm) resistance-encoding gene (ble) from the bacterial transposon tn5 for expression in n. crassa. the coding region of the ble gene was fused to the promoter and terminator regions of the n. crassa am gene. in some vectors, multiple cloning sites were placed flanking the ble gene to provide a versatile ble cassette. when introduced into ...19901699844
the apocytochrome b gene of chlamydomonas smithii contains a mobile intron related to both saccharomyces and neurospora introns.the mitochondrial dna of the two interfertile algal species chlamydomonas smithii and chlamydomonas reinhardtii are co-linear with the exception of ca. 1 kb insertion (the alpha insert) present in c. smithii dna only. in vegetative diploids resulting from interspecific crosses, mitochondrial genomes are transmitted biparentally except for the alpha insert which is transmitted to all c. reinhardtii molecules in a manner reminiscent of the intron-mediated conversion event that occurs at the omega ...19901701210
remnants of an ancient pathway to l-phenylalanine and l-tyrosine in enteric bacteria: evolutionary implications and biotechnological impact.the pathway construction for biosynthesis of aromatic amino acids in escherichia coli is atypical of the phylogenetic subdivision of gram-negative bacteria to which it belongs (r. a. jensen, mol. biol. evol. 2:92-108, 1985). related organisms possess second pathways to phenylalanine and tyrosine which depend upon the expression of a monofunctional chorismate mutase (cm-f) and cyclohexadienyl dehydratase (cdt). some enteric bacteria, unlike e. coli, possess either cm-f or cdt. these essentially c ...19902082822
isolation and sequence analysis of a beta-tubulin gene from aspergillus flavus and its use as a selectable altered beta-tubulin gene that confers resistance to benomyl [whose active ingredient is 2-(methoxycarbonylamino)benzimidazole (mbc)] was isolated from a dna library of aspergillus flavus and used as a selectable marker for transformation. the beta-tubulin gene was cloned into a plasmid vector containing the pyr-4 gene of neurospora crassa, and transformants were selected either for uracil prototrophy or mbc resistance. transformants selected for uracil prototrophy were of three phenotypic cl ...19902128007
tests for the genotoxicity of m-amsa, etoposide, teniposide and ellipticine in neurospora crassa.the antitumor agents m-amsa, etoposide, teniposide and ellipticine have been reported to be potent clastogens in mammalian cells but non- or weakly mutagenic in bacteria; these observations have been correlated to the interference of these chemicals with dna topoisomerase ii activity in the former, but not in the latter, organisms. the genotoxicity of these 4 agents was evaluated using ad-3 reverse- and forward-mutation tests in neurospora crassa. these agents (up to 0.8 mumole/plate) did not ca ...19902137196
deoxyhypusine/hypusine formation on a 21,000-dalton cellular protein in a neurospora crassa mutant in vivo and in vitro.hypusine formation on an 18,000-dalton cellular protein is a unique spermidine-dependent, post-translational modification that appears to be ubiquitous in mammalian cells. to determine whether this modification also exists in lower eukaryotes, we examined possible labeling in vitro and in vivo of cellular protein(s) by [3h]spermidine in a mutant strain of neurospora crassa (arge-12 ota aga) in which ornithine and polyamine synthesis could be nutritionally manipulated. because of poor uptake of p ...19902137713
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. v. irreparable mutants of genotype ad-3a ad-3b, ad-3a ad-3b nic-2, and ad-3b nic-2 result from multilocus deletion and an unexpectedly high frequency of multiple-locus mutations.more extensive complementation tests than those performed initially (webber and de serres, 1965) on a series of 832 x-ray-induced specific-locus mutations in the adenine-3 (ad-3) region of a two-component heterokaryon (h-12) of neurospora crassa (de serres, 1989a) showed that unexpectedly high frequencies of specific-locus mutations in the ad-3 region have additional, but separate, sites of recessive lethal (rlcl) damage in the immediately adjacent genetic regions. the frequencies of these x-ray ...19902138248
molecular structure of a gene, vma1, encoding the catalytic subunit of h(+)-translocating adenosine triphosphatase from vacuolar membranes of saccharomyces cerevisiae.subunit a of the vacuolar membrane h(+)-translocating adenosine triphosphatase of the yeast saccharomyces cerevisiae contains a catalytic site for atp hydrolysis. n-terminal sequences of six tryptic peptides of the subunit were determined. based on the peptide sequence information, a 39-base oligonucleotide probe was synthesized, and the gene encoding the subunit (vma1) was isolated from a genomic dna library by hybridization. the nucleotide sequence of the gene predicts a polypeptide of 1,071 a ...19902139027
purification and further characterization of the second nitrate reductase of escherichia coli k12.two nitrate reductases, nitrate reductase a and nitrate reductase z, exist in escherichia coli. the nitrate reductase z enzyme has been purified from the membrane fraction of a strain which is deleted for the operon encoding the nitrate reductase a enzyme and which harbours a multicopy plasmid carrying the nitrate reductase z structural genes; it was purified 219 times with a yield of about 11%. it is an mr-230,000 complex containing 13 atoms iron and 12 atoms labile sulfur/molecule. the presenc ...19902139607
paraquat toxicity and pyridine nucleotide coenzyme synthesis: a data correction.the decrease in pyridine nucleotide coenzymes which occurs during poisoning of escherichia coli by hyperbaric oxygen or paraquat is not due to impairment of nicotinatemononucleotide pyrophosphorylase (carboxylating) [ec] as was previously proposed (brown, o.r. et al. biochem. biophys. res. commun. 91:982-990; 1979). this was shown directly using extracts of e. coli, prepared after exposure to 1 mm paraquat or 4.2 atmospheres of oxygen. the enzyme also was not impaired in neurospora cras ...19902139629
two complex regions, including a tata sequence, are required for transcription by rna polymerase i in neurospora order to define the rna polymerase i transcriptional apparatus and how it might interact with regulatory signals, the dna sequences necessary for 40s rrna transcription in neurospora crassa were determined. a systematic set of deletion, substitution and insertion mutations were assayed in a homologous in vitro system. the sequences required for transcription of the gene consist of two large domains (i and ii) from -113 to -37, and -29 to +4, respectively. complete deletion of either domain ab ...19902139932
mating type and mating strategies in the heterothallic species neurospora crassa, strains of opposite mating type, a and a, must interact to give the series of events resulting in fruiting body formation, meiosis, and the generation of dormant ascospores. the mating type of a strain is specified by the dna sequence it carries in the mating type region; strains that are otherwise isogenic can mate and produce ascospores. the dna of the a and a regions have completely dissimilar sequences. probing dna from strains of each mating t ...19902140508
molybdenum cofactor requirement for in vitro activation of apo-molybdoenzymes of escherichia coli.the apo-nitrate reductase precursor in an escherichia coli chlb mutant preparation obtained following growth in the presence of tungstate is activated by incubation with protein fa and a heat-treated preparation from an e. coli crude extract. we show that the requirement for heat-treated e. coli crude extract can be fulfilled by material obtained from either of two heat-denatured purified e. coli molybdoenzymes, namely nitrate reductase or trimethylamine n-oxide reductase. apo-trimethylamine n-o ...19902141097
the neurospora crassa arg-2 locus. structure and expression of the gene encoding the small subunit of arginine-specific carbamoyl phosphate synthetase.we have characterized genomic and cdna clones for arg-2, the gene encoding the small subunit of the neurospora crassa arginine-specific carbamoyl phosphate synthetase (cps-a), and examined its transcriptional regulation. the polypeptide's predicted amino acid sequence (453 residues) is 56% and 36% identical with the sequences of the homologous polypeptides of saccharomyces cerevisiae and escherichia coli, respectively. the arg2 polypeptide has an additional amino-terminal domain with the hallmar ...19902141606
cys-3, the positive-acting sulfur regulatory gene of neurospora crassa, encodes a sequence-specific dna-binding protein.cys-3, the positive-acting master sulfur regulatory gene of neurospora crassa, turns on the expression of an entire set of unlinked structural genes which encode sulfur-catabolic enzymes. cys-3 encodes a protein of 236 amino acid residues and contains a potential bipartite dna-binding domain which consists of a leucine zipper and an adjacent highly basic region. gel band mobility shift and dna footprint experiments were used to demonstrate that the cys3 protein, expressed in escherichia coli, bi ...19902142156
neurospora crassa a mating-type region.the mating-type locus of the haploid filamentous fungus neurospora crassa is a regulatory region that controls entry into the sexual cycle and prevents formation of mixed mating-type heterokaryons in the vegetative phase. the locus consists of alternative sequences called a and a. the a mating-type dna sequence of neurospora crassa is composed of a region of 5301 base pairs that has little similarity to the sequence present at the mating-type locus in an a mating-type strain. however, the sequen ...19902142303
neurospora crassa a mating-type region.the a mating-type region of neurospora crassa controls several major events in both the sexual and asexual phases of the fungal life cycle. this 3235-base-pair dna segment is not homologous to the comparable genetic region of the a mating type. the unique a and a regions are bordered by nearly identical dna sequences. the a genetic region contains at least two functional segments. one segment encodes a perithecium maturation function that is dependent on the second segment for phenotypic express ...19902142304
nit-2, the major positive-acting nitrogen regulatory gene of neurospora crassa, encodes a sequence-specific dna-binding protein.the nit-2 major nitrogen regulatory gene of neurospora crassa turns on the expression of various unlinked structural genes that specify nitrogen-catabolic enzymes under nitrogen-limitation conditions. the nit-2 gene encodes a protein of 1036 amino acid residues with a single zinc finger and a downstream basic region that may make up a dna-binding domain. the zinc-finger domain of the nit2 protein was synthesized in two ways to examine its dna-binding activity with gel-band-mobility shift and dna ...19902142530
primary structure of the non-transcribed spacer region and flanking sequences of the ribosomal dna of neurospora crassa and comparison with other organisms.the non-transcribed spacer (nts) region of the rdna of neurospora crassa contains the transcription regulatory sequences. we isolated a 3.4 kb ecori fragment from wild type n.crassa rdna and cloned in the plasmid pbr325 at the ecori site. the insert contains the entire nts region along with the flanking sequences. nucleotide sequencing of 3592 nt shows many interesting features like: the nts region is rich in g+c content (65% g+c); it contains the conserved rrna processing site 6 (with the nucle ...19902142594
molecular cloning of subunits of complex i from neurospora crassa. primary structure and in vitro expression of a 22-kda polypeptide.a lambda gt11 cdna expression library was screened with antibodies directed against individual subunits of complex i from neurospora crassa. clones encoding cytoplasmically synthesized polypeptides with apparent molecular masses of 22, 29, 31, and 33 kda were isolated. northern blot analysis revealed that the corresponding genes are transcribed into mrna species of about 0.85, 0.95, 1.3, and 1.4 kilobases, respectively. further characterization of clones encoding the 22-kda subunit was performed ...19902142943
heterozygous effects of x-ray-induced specific locus mutations in the ad-3 region of neurospora crassa: implications for human genetic risk assessment. 19902143295
molecular cloning and nucleotide sequence of full-length cdna for ascorbate oxidase from cultured pumpkin cells.a lambda gt11 cdna expression library was constructed from size-fractionated poly(a)-rich rna of cultured pumpkin cells. a full-length cdna clone for ascorbate oxidase mrna was selected from the library by screening with synthetic oligonucleotides designed from the amino-terminal sequence of ascorbate oxidase protein. the identity of the clone was confirmed by comparing the amino acid sequence deduced by nucleotide sequence analysis with that determined for the amino-terminal sequence of pumpkin ...19902143984
evidence for the presence of a proton pump of the vacuolar h(+)-atpase type in the ruffled borders of osteoclasts.microsomal membrane vesicles prepared either from chicken medullary bone or isolated osteoclasts were shown to have atp-dependent h(+)-transport activity. this activity was n-ethylmaleimide-sensitive but resistant to oligomycin and orthovanadate, suggesting a vacuolar-type atpase. furthermore, immunological cross-reactivity of 60- and 70-kd osteoclast membrane antigens with neurospora crassa vacuolar atpase was observed when analyzed by immunoblotting. same antibodies labeled only osteoclasts in ...19902144003
characterization of eukaryotic dna polymerases: aphidicolin resistant mutants of neurospora with altered dna polymerase.sucrose density gradient analysis of neurospora cell free extract showed at least three distinct peaks of enzyme activity; of these, a high molecular weight enzyme was identified as dna polymerase alpha because of its sensitivity to aphidicolin and to nem. dna polymerase mutants of neurospora crassa were isolated by their resistance to aphidicolin, a specific inhibitor of the eukaryotic dna polymerase alpha. some mutants showed an increase in the specific activity of the enzyme. one mutant (e-2- ...19902144049
carotenoid desaturases from rhodobacter capsulatus and neurospora crassa are structurally and functionally conserved and contain domains homologous to flavoprotein disulfide oxidoreductases.the characteristic red color of some photosynthetic bacteria and the orange color of neurospora conidia is due to the presence of carotenoids, photoprotective pigments synthesized by plants, algae, bacteria, and fungi. generally, carotenoids are tetraterpenes in which absorption of visible light and photoprotection are mediated by a chain of conjugated double bonds, the chromophore, which is formed by successive desaturations of phytoene, a colorless precursor. the genes al-1 and crti mediate th ...19902144293
neurospora crassa cdna clones coding for a new member of the ras protein family.a new member of the ras gene family was characterized from neurospora crassa cdna libraries. the clone designated nc-ras codes for a polypeptide containing 213 amino acids (mr 24,000). this polypeptide is 84% homologous to the h-ras-1 domain comprising the first 80 amino acids and 60% homologous to the next 84 residues. the nc-ras polypeptide contains all the well-known sequences involved in the interaction with gtp/gdp, the recognition of the y13-259 neutralizing antibody, the 'effector site' f ...19902146163
structure, exon pattern, and chromosome mapping of the gene for cytosolic copper-zinc superoxide dismutase (sod-1) from neurospora crassa.a 4.8-kilobase bamhi-hindiii fragment encoding the entire neurospora crassa cuzn superoxide dismutase gene (herein designated sod-1) was isolated from a genomic library using two 60-base deoxyoligonucleotide probes corresponding to the published n. crassa amino acid sequence. the nucleotide sequence of the gene encodes an amino acid sequence matching the published protein sequence at 152 of 153 positions. codon preference shows an unusually strong bias such that only 32 of the possible 61 codons ...19902146266
nucleotide sequence and analysis of nmr, a negative-acting regulatory gene in the nitrogen circuit of neurospora neurospora the expression of a set of unlinked structural genes, which allows utilization of various nitrogen-containing compounds, is controlled by the positive-acting nit-2 gene and the negative-acting nmr gene. the nucleotide sequence of the nmr gene has been determined and a long open reading frame which encodes a putative protein of 54854 daltons has been identified. a full-length cdna clone was obtained and its the sequence revealed that the nmr gene contains no introns. the transcripti ...19902146484
molecular analysis of nuc-1+, a gene controlling phosphorus acquisition in neurospora response to phosphorus starvation, neurospora crassa makes several enzymes that are undetectable or barely detectable in phosphate-sufficient cultures. the nuc-1+ gene, whose product regulates the synthesis of these enzymes, was cloned and sequenced. the nuc-1+ gene encodes a protein of 824 amino acids with a predicted molecular weight of 87,429. the amino acid sequence shows homology with two yeast proteins whose functions are analogous to that of the nuc-1 protein. two nuc-1+ transcripts of ...19902146493
purification of chorismate synthase from a cell culture of the higher plant corydalis sempervirens pers.chorismate synthase (ec was purified from a cell suspension culture of corydalis sempervirens almost 1000-fold to near homogeneity. the subunit mr estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate was 41,900. the mr of the native enzyme was estimated to be 80,100 by gel filtration, suggesting a dimeric structure. antisera directed against the 41.9-kda protein also reacted with the native enzyme. further confirmation of the identity of the purified ...19902146922
the 49 k subunit of nadh: ubiquinone reductase (complex i) from neurospora crassa mitochondria: primary structure of the gene and the protein.the primary structure of the 49 k subunit of the respiratory chain nadh:ubiquinone reductase (complex i) from neurospora crassa was determined by sequencing cdna, genomic dna and the n-terminus of the mature protein. the sequence lengths correlate to a molecular mass of 54,002 daltons for the preprotein and 49,239 daltons for the mature protein. the presequence consists of 42 amino acids of typical composition for sequences which target nuclear-encoded proteins into mitochondria. the mature prot ...19902147127
the beta-tubulin gene of epichloë typhina from perennial ryegrass (lolium perenne).epichloë typhina is a biotrophic fungal pathogen which causes choke disease of pooid grasses. the anamorphic state, acremonium typhinum, is placed in the section albo-lanosa along with related, mutualistic, seed-disseminated endophytes. as an initial study of gene structure and evolution in epichloë and related endophytes, the beta-tubulin gene, tub2, of the perennial ryegrass choke pathogen (etprg) was cloned and sequenced. the coding sequence and the predicted beta-tubulin amino acid sequence ...19902147581
deletion analysis of domain independence in the trp1 gene product of neurospora crassa.the trifunctional trp1 gene from neurospora crassa (n-trp1) was subcloned into the yeast-escherichia coli shuttle vector yep13 and expressed in saccharomyces cerevisiae. the three activities of the n-trp1 gene product were detected in yeast mutants that lacked either n-(5'-phosphoribosyl) anthranilate (pra) isomerase or both the glutamine amidotransferase function of anthranilate synthase and indole-3-glycerol phosphate (ingp) synthase. the protein was detected on immunoblots only as the full le ...19902147978
induced expression of the aspergillus nidulans qute gene introduced by transformation into neurospora crassa.the qa-2 gene of neurospora crassa encodes catabolic dehydroquinase which catabolizes dehydroquinic acid to dehydroshikimic acid. the qute gene of aspergillus nidulans corresponds to the qa-2 gene of n. crassa. the plasmid peh1 containing the qute gene from a. nidulans was used to transform a qa-2- strain of n. crassa. in southern blot analyses, dnas isolated from these transformants hybridized specifically to the qute gene probe. northern blot analyses indicated that qute mrna was produced in t ...19902148798
expression of a neurospora crassa metallothionein and its variants in escherichia coli.the neurospora crassa metallothionein (nc) synthesis gene was cloned and expressed in escherichia coli in two different expression vectors (ping2 and pua7), both under the regulation of the salmonella typhimurium arabinose operon. upon induction with arabinose, the ping2-nc vector expressed as inclusion body-localized arab'::nc fusion protein of 21 kilodaltons. the pua7-nc vector expressed a 5.3-kilodalton lpp::nc fusion protein anchored to the outer membrane of the cell. cells expressing the nc ...19902148862
purification and characterization of catalase from a facultative alkalophilic bacillus.catalase was purified to an electrophoretically homogeneous state from the facultative alkalophilic bacterium, bacillus yn-2000, and some of its properties were studied. its molecular weight was 282,000 and its molecule was composed of four identical subunits. the enzyme contained two protoheme molecules per tetramer. the enzyme showed an absorption spectrum of typical high-spin ferric heme with a peak at 406 nm in the oxidized form and peaks at 440, 559, and 592 nm in the reduced form. in contr ...19902149854
atp-induced protyrosinase synthesis and carboxyl-terminal processing in neurospora crassa.the effects of 3'-5' cyclic amp and atp upon tyrosinase induction in neurospora crassa were examined. northern analysis of total cellular rna revealed rapid de novo synthesis of protyrosinase after addition of these substances to stationary-phase mycelia. the maturation of protyrosinase in crude extracts of mycelia was followed by western analysis. polyclonal rabbit antiserum directed against the denatured carboxyl-terminal extension of protyrosinase does recognize the proform and several interm ...19902150229
site-directed mutagenesis of the 'zinc finger' dna-binding domain of the nitrogen-regulatory protein nit2 of neurospora.the major nitrogen-regulatory gene nit-2 of neurospora crassa activates the expression of numerous unlinked structural genes which specify nitrogen-catabolic enzymes during conditions of nitrogen limitation. the nit-2 gene encodes a regulatory protein of 1036 amino acid residues with a single 'zinc finger' and a downstream basic region, which together may constitute a dna-binding domain. the zinc finger domain of the nit2 protein was synthesized in vitro and also expressed as a fusion protein in ...19902150539
aberrant mitochondrial processing of chimaeric import precursors containing subunits 8 and 9 of yeast mitochondrial atp synthase.a set of chimaeric precursors which contain the same leader sequences but different passenger proteins has been analyzed for the site of protease cleavage following import into yeast mitochondria. each precursor comprises the leader of neurospora crassa subunit 9 of mitochondrial atp synthase fused to subunit 8 or 9 of the corresponding yeast enzyme. precursors containing the first five residues of mature n. crassa subunit 9 interposed between the leader and the yeast passenger protein were clea ...19902151020
[genetic engineering in filamentous fungi: cloning of the invertase gene from neurospora crassa].the invertase wild type gene of n. crassa was cloned into the yrp7 yeast vector. this recombinant plasmid was selected by functional complementation of an invertaseless mutant strain of s. cerevisiae. the isolated recombinant plasmid (named pnc2) carries a 7.6 kb bamhi dna fragment from n. crassa. the cloned dna hybridized with the n. crassa genomic dna and transformed an invertase mutant of n. crassa inv- to inv+. transformation of n. crassa inv- to inv+ seems to take at least two different int ...19902151941
neurospora endo-exonuclease is immunochemically related to the recc gene product of escherichia coli.immunochemical cross-reaction between the endo-exonuclease of neurospora crassa, an enzyme previously implicated in recombination and recombinational dna repair, and the recc-encoded polypeptide of escherichia coli has been detected by immunoblotting extracts of strains of e. coli having a deletion that includes the recbcd genes but carrying multicopy plasmids bearing all three of the recbcd genes or only one or two of these genes. it was predicted that homology would also be found at the amino ...19902152915
mitochondrial dna sequence analysis of the cytochrome oxidase subunit ii gene from podospora anserina. a group ia intron with a putative alternative splice site.a 5 kb region of the 95 kb mitochondrial genome of podospora anserina race s has been mapped and sequenced (1 kb = 10(3) base-pairs). this dna region is continuous with the sequence for the nd4l and nd5 gene complex in the accompanying paper. we show that this sequence contains the gene for cytochrome oxidase subunit ii (coii). this gene is 4 kb in length and is interrupted by a subgroup ib intron (1267 base-pairs (bp) in length) and a subgroup ia intron (1992 bp in length). this group ia intron ...19902157023
endo-exonuclease of aspergillus nidulans.endo-exonuclease (ee) has been found in both active and inactive, but trypsin-activatable, forms in aspergillus nidulans. active ee was present mainly in nuclei, mitochondria, and vacuoles, while trypsin-activatable ee was mainly in the cytosol. the active form accounts for over 90% of the neutral deoxyribonuclease activity extracted from mycelia. a single strand (ss) dna-binding ee associated with a 28 kilodalton (kda) polypeptide was partially purified and characterized. it was found to closel ...19902161674
regulation of inorganic sulfate activation in filamentous fungi. allosteric inhibition of atp sulfurylase by 3'-phosphoadenosine-5'-phosphosulfate.atp sulfurylases from penicillium chrysogenum, penicillium duponti, aspergillus nidulans, and neurospora crassa are strongly inhibited by 3'-phosphoadenosine-5'-phosphosulfate (paps), the product of the second (adenosine-5'-phosphosulfate kinase-catalyzed) reaction in the two-step activation of inorganic sulfate. the v versus [paps] plots are sigmoidal. at physiological concentrations of mgatp (0.17-3 mm) and so4(2-) (0.4-10 mm), the [i]0.5 for paps inhibition of the p. chrysogenum enzyme is 35- ...19902162344
nucleotide sequence and nuclear protein binding of the two regulatory sequences upstream of the am (gdh) gene in neurospora.we have constructed a series of deletions in the 5' non-coding sequences of the cloned neurospora crassa am gene which specifies nadp specific glutamate dehydrogenase. all of the deletions begin at -4.4 kb with respect to the am transcription start site and extend for various distances toward the am gene. using vectors with a truncated fragment of the am gene, we introduced these deletions into the chromosome upstream of am by transformation. analysis of glutamate dehydrogenase expression in str ...19902164625
import into mitochondria of precursors containing hydrophobic passenger proteins: pretreatment of precursors with urea inhibits import.we have studied the import into isolated yeast mitochondria of three hydrophobic passenger proteins attached to the n-terminal cleavable presequence of mitochondrial atpase subunit 9 from neurospora crassa. one natural precursor (pn9) contained n. crassa subunit 9; two chimaeric precursors, n9l/y8-1 and n9l/y9-2, respectively contained yeast mitochondrial atpase subunits 8 and 9. in the absence of urea, pn9 and n9l/y8-1 are imported efficiently but n9l/y9-2 is not imported. after pretreatment of ...19902168755
plant and fungus calmodulins are polyubiquitinated at a single site in a ca2(+)-dependent plants ca2+ plays a crucial role as second messenger. thus calmodulin is one of the most important signal transducing molecules for metabolic regulation in plants. previously we showed that bovine testis calmodulin can be covalently coupled at one site to ubiquitin in a ca2(+)-dependent manner in the presence of atp/mg2+ by ubiquityl-calmodulin synthetase. since calmodulin from spinach has 13 amino acid sequence differences to bovine calmodulin - two of them in ca2(+)-binding loops - it was u ...19902172031
spatial and biological characterisation of the complete quinic acid utilisation gene cluster in aspergillus nidulans.heterologous probing of restriction digests of chromosomal dna from aspergillus nidulans with radioactively labelled probes encoding dehydroshikimate dehydratase (qa-4) and a repressor gene (qa1-s) from neurospora crassa revealed a pattern of hybridisation inconsistent with an equivalent single copy of each gene in a. nidulans. screening of size-selected and total genome a. nidulans dna libraries allowed the isolation of four unique classes of sequence, two of which hybridised to the qa-4 probe, ...19902175387
import of adp/atp carrier into mitochondria: two receptors act in parallel.we have identified the yeast homologue of neurospora crassa mom72, the mitochondrial import receptor for the adp/atp carrier (aac), by functional studies and by cdna sequencing. mitochondria of a yeast mutant in which the gene for mom72 was disrupted were impaired in specific binding and import of aac. unexpectedly, we found a residual, yet significant import of aac into mitochondria lacking mom72 that occurred via the receptor mom19. we conclude that both mom72 and mom19 can direct aac into mit ...19902177474
the general mitochondrial matrix processing protease from rat liver: structural characterization of the catalytic subunit.a critical step in the import of nuclear-encoded precursor proteins into mitochondria involves proteolytic cleavage of their amino-terminal leader peptides by processing proteases found in the mitochondrial matrix. we report here the characterization of the general matrix processing protease from rat liver mitochondria. the final enzyme preparation consisted of two polypeptides, a catalytically active 55-kda subunit and a 52-kda one. to deduce the complete primary structure of the 55-kda subunit ...19902236012
the development of a heterologous transformation system for the cellulolytic fungus trichoderma reesei based on a pyrg-negative mutant strain.six uridine auxotroph mutants of trichoderma reesei qm 9414 were isolated by resistance to 5-fluoroorotic acid and one strain was identified as omp-decarboxylase negative (pyr-) by a radiometric enzyme assay. transformation to uridine prototrophy was achieved with the pyr4 gene of neurospora crassa (up to 1500 transformants/micrograms) and with pyra of aspergillus niger (700-800 transformants/micrograms). in many transformants the pyr+ function seems to be present as extrachromosomal dna. there ...19902245476
mycenon, a new metabolite from a mycena species ta 87202 (basidiomycetes) as an inhibitor of isocitrate lyase.mycenon (c11h5cl3o3), a new inhibitor of isocitrate lyase (ec was isolated from the culture broth of a basidiomycete, mycena sp. mycenon is a novel chlorinated benzoquinone derivative which is also active against bacteria and fungi. malate synthase (ec the second key enzyme of the glyoxylate cycle was not affected by mycenon. isocitrate lyase preparations from plants, bacteria and fungi were sensitive. the following ki-values for mycenon have been determined: ricinus communis, ...19902258323
expression in saccharomyces cerevisiae of a gene associated with cytoplasmic male sterility from maize: respiratory dysfunction and uncoupling of yeast mitochondria.we asked whether the mitochondrial t-urf13 gene, associated with the male sterility phenotype of t cytoplasm in maize, can be expressed in saccharomyces cerevisiae and whether this expression can mimic the effects observed in maize. we introduced the universal code equivalent of the t-urf13 gene into the s. cerevisiae nucleus by transformation and directed its translation product into mitochondria by means of a fusion with the targeting presequence from neurospora crassa at-pase subunit 9. we sh ...19902259341
an evolutionary comparison of acinetobacter calcoaceticus trpf with trpf genes of several organisms.the deduced amino acid sequence of acinetobacter calcoaceticus n-(5'-phosphoribosyl) anthranilate isomerase (prai), which is coded by trpf, was compared with trpf of caulobacter crescentus, escherichia coli, bacillus subtilis, saccharomyces cerevisiae, neurospora crassa, and aspergillus nidulans. sixty percent of identical or similar amino acids were located in alpha/beta tim (triose-phosphate isomerase) barrels and in residues important in substrate binding and catalysis. in addition, the analy ...19902299982
expression in yeast of the t-urf13 protein from texas male-sterile maize mitochondria confers sensitivity to methomyl and to texas-cytoplasm-specific fungal toxins.the mitochondrial gene t-urf13 from maize (zea mays l.) with texas male-sterile (t) cytoplasm codes for a unique 13 kd polypeptide, t-urf13, which is implicated in cytoplasmic male sterility and sensitivity to the insecticide methomyl and to host-specific fungal toxins produced by helminthosporium maydis race t (hmt toxin) and phyllosticta maydis (pm toxin). a chimeric gene coding for t-urf13 fused to the mitochondrial targeting peptide from the neurospora crassa atp synthase subunit 9 precursor ...19902303028
the purification and characterization of 3-dehydroquinase from streptomyces coelicolor.the enzyme 3-dehydroquinase was purified over 4000-fold to homogeneity from streptomyces coelicolor. the subunit mr estimated from polyacrylamide-gel electrophoresis in the presence of sds was 16,000. the native mr estimated by gel filtration on a superose 6 column was 209,000, indicating that the enzyme is a large oligomer. the enzyme was found to be extremely thermostable. this stability, along with the structural and kinetic properties of the enzyme, suggest that it is very similar to the qui ...19902306211
dna sequence analysis of the mitochondrial nd4l-nd5 gene complex from podospora anserina. duplication of the nd4l gene within its intron.a 15 kb region of the 100 kb mitochondrial genome of podospora anserina has been mapped and sequenced (1 kb = 10(3) base-pairs). the genes for nd4l and nd5 are identified as contiguous genes with overlapping termination and initiation codons. in race a (101 kb) the gene for nd4l (4.3 kb) has a gene duplication within an intron including a second subgroup ic intron. race s (95 kb) lacks this second gene complex. each intron has the identical 5' exon boundary. secondary structure analysis showed t ...19902319602
cloning and analysis of beta-tubulin gene from a protoctist.we have isolated and characterized by restriction endonuclease mapping, transcription pattern, and dna sequencing a beta-tubulin gene from the coenocytic freshwater protoctist, achlya klebsiana. the gene is intronless and has a single open reading frame that encodes a 444-amino acid residue polypeptide of mr 49,856. the protein shows a high degree of homology to other beta-tubulins, 85% identity to human beta-tubulin and 89% identity to beta-tubulin of the sporozoan (also a protoctist) plasmodiu ...19902394720
nuclear pre-mrna introns: analysis and comparison of intron sequences from tetrahymena thermophila and other eukaryotes.we have sequenced 14 introns from the ciliate tetrahymena thermophila and include these in an analysis of the 27 intron sequences available from seven t. thermophila protein-encoding genes. consensus 5' and 3' splice junctions were determined and found to resemble the junctions of other nuclear pre-mrna introns. unique features are noted and discussed. overall the introns have a mean a + t content of 85% (21% higher than neighbouring exons) with smaller introns tending towards a higher a + t con ...19902402440
comparison and cross-species expression of the acetyl-coa synthetase genes of the ascomycete fungi, aspergillus nidulans and neurospora crassa.the genes encoding the acetate-inducible enzyme acetyl-coenzyme a synthetase from neurospora crassa and aspergillus nidulans (acu-5 and faca, respectively) have been cloned and their sequences compared. the predicted amino acid sequence of the aspergillus enzyme has 670 amino acid residues and that of the neurospora enzyme either 626 or 606 residues, depending upon which of the two possible initiation codons is used. the amino acid sequences following the second alternative aug show 86% homology ...19901972535
use of nuclear dna restriction fragment length polymorphisms to analyze the diversity of the aspergillus flavus group: a. flavus, a. parasiticus, and a. nomius.recombinant dna clones carrying high-copy or low-copy sequences from aspergillus nidulans and neurospora crassa were used to identify restriction fragment length polymorphisms (rflps) diagnostic for members of the a. flavus group: a. flavus, a. parasiticus, and a. nomius. these fungi were resolved into three distinct categories when they were grouped according to rflp patterns. subgroups within these categories were also evident. this limited rflp analysis of nuclear dna of members of the a. fla ...19901976300
a neurospora crassa ribosomal protein gene, homologous to yeast cry1, contains sequences potentially coordinating its transcription with rrna genes.we have isolated and sequenced a neurospora crassa ribosomal protein gene (designated crp-2) strongly homologous to the rp59 gene (cry1) of yeast and the s14 ribosomal protein gene of mammals. the inferred sequence of the crp-2 protein is more homologous (83%) to the mammalian s14 sequence than to the yeast rp59 sequence (69%). the gene has three intervening sequences (ivss) two of which are offset 7 bp from the position of ivss in the mammalian genes. none correspond to the position of the ivs ...19901977135
premeiotic disruption of the neurospora crassa malate synthase gene by native and divergent dnas.repeat-induced point mutation (rip) has been used to generate new mutations in the previously uncharacterised gene for malate synthase in neurospora crassa. molecular clones carrying the am (nadp-glutamate dehydrogenase) gene and the malate synthase gene from either n. crassa or aspergillus nidulans have been introduced into neurospora as ectopic duplicate copies by transformation, selecting for the am+ function in a deletion host. a number of meiotic progeny derived from these transformants wer ...19901979142
nucleotide sequence of a neurospora crassa ribosomal protein gene. 19902147995
nucleotide sequence of the exons of the large subunit rrna of neurospora crassa mitochondria. 19901701879
genes expressed during conidiation in neurospora crassa: molecular characterization of con-13.asexual development in neurospora crassa proceeds through a series of discrete morphological stages that culminate in the production of dormant spores called conidia. changes in the pattern of gene expression parallel the morphological transformations associated with conidiation. as a prerequisite to the analysis of developmental gene expression in n. crassa, several genes of unknown function that are preferentially expressed during conidiation were isolated [berlin and yanofsky, mol. cell. biol ...19902148538
glutamine metabolism and cycling in neurospora crassa.[this corrects the article on p. toc in vol. 54.].199016350247
5-benzylidene pyrrolones. iv--synthesis and antifungal activity of some 5-benzylidene derivatives of 1, order to investigate the antifungal activity of pyrrolones, the synthesis of derivatives of 5-benzylidene-1,2,-dimethyl-3-carbethoxy-pyrrol-4-one was achieved by a one-step reaction. the condensation reaction was applied to the above-mentioned heterocycle and seven substituted benzaldehydes were obtained providing the entitled compounds, of which six are original. they have preferential e configuration. antifugal data against neurospora crassa in comparison with ketoconazole showed that many ...19902151022
generation of new functional mutant alleles by premeiotic disruption of the neurospora crassa am the further analysis of a cross in which the mis-sense allele, am3, of the neurospora crassa am (glutamate dehydrogenase) gene was present in one parent together with two ectopic wild-type gene copies, one ascus was identified in which the two ectopic copies had been inactivated by the rip process whereas the am3 allele continued to produce its characteristic enzyme variety in active, but heat-sensitive, form. the am3 allele had also acquired a new hindiii restriction site. it had no detectab ...19902150348
cytosolic calcium homeostasis in fungi: roles of plasma membrane transport and intracellular sequestration of calcium.cytosolic free calcium ([ca2+]c) has been measured in the mycelial fungus neurospora crassa with ca2(+)-selective microelectrodes. the mean value of [ca2+]c is 92 +/- 15 nm and it is insensitive to external ph values between 5.8 and 8.4. simultaneous measurement of membrane potential enables the electrochemical potential difference for ca2+ across the plasma membrane to be estimated as about -60 kj.mol-1-a value that cannot be sustained either by a simple ca2(+)-atpase, or, in alkaline condition ...19902147513
regulation of branched-chain amino acid biosynthesis in neurospora crassa: cloning and characterization of the leu-1 and ilv-3 genes.the genes coding for the branched-chain amino acid biosynthetic enzymes comprise an integrated regulatory system. the expression of the several structural genes coding for enzymes of the isoleucine-valine and leucine pathways is controlled in parallel by the positive-acting regulatory gene, leu-3. the leu-1 and ilv-3 genes, coding for beta-isopropyl-malate dehydrogenase and aceto-hydroxyacid synthase, respectively, were cloned from a cosmid library. restriction fragment length polymorphism analy ...19901980003
studies on the sedimentation behavior of the neurospora crassa plasma membrane h(+)-atpase synthesized in vitro and integrated into homologous microsomal membranes.rna transcripts that encoded the neurospora crassa plasma membrane h(+)-atpase (pma+), a polytopic integral membrane protein, and the pma+344, a truncated pma+ with the amino terminal 344 amino acids, were translated in a n. crassa in vitro system. the microsomal membranes integrated products were insensitive to extraction by na2co3 (ph 11.5). the velocity sedimentation behavior of the in vitro synthesized pma+ were examined under various conditions. the pma+ migrated on linear sucrose gradients ...19902148269
expression of tyrosinase in vegetative cultures of neurospora crassa transformed with a metallothionein promoter/protyrosinase fusion gene.wild-type neurospora crassa, strain singapore, was transformed with a n. crassa metallothionein promoter/protyrosinase fusion gene. transformants produced tyrosinase during vegetative growth, as determined by western analyses and activity assays. this is in sharp contrast to wild-type strains, where this enzyme is only expressed in situations of starvation or sexual differentiation. complete integration of a 400 bp metallothionein promoter-fragment leads to constitutive expression of protyrosina ...19902147580
characterization of a novel plasmid-like element in neurospora crassa derived mostly from the mitochondrial dna.we have identified a plasmid-like element within mitochondria of neurospora crassa strain stp-b1. it is derived from the ecori-4 and ecori-6 regions of the mitochondrial dna, and an additional 124 bp dna segment of unknown origin. the plasmid dna consists of an oligomeric series of circular molecules of monomer length 2.2 kbp. the abundance of the plasmid suggests its autonomous replication and the presence of an efficient origin of replication. an unusually large number of palindromes capable o ...19902145549
molecular cloning of the l-amino-acid oxidase gene from neurospora crassa.the addition of d-phenylalanine to starved cultures of neurospora crassa leads to de novo synthesis of l-amino-acid oxidase. poly(a) rna from d-phenylalanine-treated mycelium was therefore used to generate a cdna library which was subsequently screened by hybrid-selected translation. a positive l-amino-acid oxidase clone served as a probe to isolate the complete gene from a genomic library of n. crassa. the nucleotide sequence obtained revealed an open reading frame coding for a protein of 695 a ...19902145270
tad, a line-like transposable element of neurospora, can transpose between nuclei in heterokaryons.the tad transposon of neurospora crassa appears to be a line-like element with very restricted distribution within the genus neurospora. when forced heterokaryons were constructed between strains which did and did not contain tad, the nuclei of the naive nuclear type rapidly acquired tad elements. the elements acquired by naive nuclei are active, since they can pass tad to other naive nuclei in subsequent heterokaryons. when heterokaryons are passaged by serial transfer, the load of acquired tad ...19902174012
heat shock response in neurospora crassa: purification and some properties of hsp 80.the heat shock response of neurospora crassa was investigated. a 80-kilodalton heat shock protein (hsp 80) was purified to near homogeneity from heat-shocked mycelial extracts employing ammonium sulphate fractionation, gel filtration, and ion-exchange and affinity chromatography. it was observed to migrate as a single band on one-dimensional sodium dodecyl sulphate--polyacrylamide gels, with a molecular mass of approximately 83 kilodaltons (kda). on two-dimensional gels it resolved into four pol ...19902148482
cpc-2, a new locus involved in general control of amino acid synthetic enzymes in neurospora neurospora crassa starvation for single amino acids leads to derepression of enzymes in many amino acid synthetic pathways. regulation occurs at the level of transcription via "general amino acid (or cross-pathway) control". in this paper a new regulatory gene, cpc-2, is described that specifies a positive, trans-acting effector involved in this control. this gene, located on linkage group vii, was identified by a recessive mutation, u142, which results in sensitivity for two amino acid analo ...19902147403
the nucleotide excision repair epistasis group in neurospora crassa.dna repair mutants in eucaryotes are normally assigned to three epistasis groups. each epistasis group represents a "pathway" for dna repair. the pathways are commonly designated (1) nucleotide excision repair, (2) recombination repair and (3) mutagenic repair. an excision repair epistasis group has been established in neurospora and the mutants assigned to this group should be limited in their ability to excise pyrimidine dimers and other bulky lesions from dna. using a pyrimidine dimer-specifi ...19902147402
expansion and contraction of the nucleolus organizer region of neurospora: changes originate in both proximal and distal segments.previously we have shown that the nucleolus organizer region (nor) of neurospora crassa changes size frequently during the premeiotic portion of the sexual phase. here, we have investigated whether these changes in size originate only in specific regions of the nor, or are distributed throughout the nor. in two special strains of neurospora, the nor was divided into proximal and distal segments. in the first, the nor was divided by a translocation breakpoint and, in the second, the nor was divid ...19902147160
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. vii. genetic lesions resulting in gene/point mutations at the ad-3b locus have different dose-response relationships.genetic characterization of x-ray-induced ad-3 mutants, induced in a two-component heterokaryon (h-12) of neurospora crassa, has been performed to determine genotype, patterns of allelic complementation, and leakiness, and to distinguish gene/point mutations from multilocus deletions and multiple locus mutations (de serres, 1989c, 1990a). the array of genotypes in the classes and subclasses in the spectrum of ad-3 mutants induced by a mutagenic agent constitute its mutagenicity profile; for x-ra ...19902145510
cloning, sequence, and photoregulation of al-1, a carotenoid biosynthetic gene of neurospora crassa.carotenoid biosynthesis is regulated by blue light during growth of neurospora crassa mycelia. we have cloned the al-1 gene of n. crassa encoding the carotenoid-biosynthetic enzyme phytoene dehydrogenase and present an analysis of its structure and regulation. the gene encodes a 595-residue polypeptide that shows homology to two procaryotic carotenoid dehydrogenases. rna measurements showed that the level of al-1 mrna increased over 70-fold in photoinduced mycelia. transcription run-on studies i ...19902144609
molecular cloning and analysis of the scon-2 negative regulatory gene of neurospora crassa.the sulfur regulatory system of neurospora crassa is composed of a group of highly regulated structural genes (e.g., the gene encoding arylsulfatase) that are under coordinate control of scon+ (sulfur controller) negative and cys-3+ positive regulatory genes. in scon-1 (previously designated sconc) and scon-2 mutants, there is constitutive expression of sulfur structural genes regardless of the sulfur level available to the cells. the scon-2+ gene was cloned by sib selection screening of a cosmi ...19901975945
primary structure and expression of a nuclear-coded subunit of complex i homologous to proteins specified by the chloroplast genome.a 31-kda subunit of complex i from neurospora crassa, of nuclear origin, was cloned. the precursor polypeptide (33 kda) could be efficiently expressed in an in vitro system for transcription and translation. the processing of the precursor to the mature protein was also obtained in vitro. an open reading frame coding for a precursor protein of 283 amino acids (32247 da) was found by dna sequencing. the predicted primary structure shows significant homology with proteins made in chloroplast. this ...19902145832
the reaction of cn- with the binuclear copper site of neurospora tyrosinase: its relevance for a comparison between tyrosinase and hemocyanin active sites.the equilibrium and the kinetics of the reaction between neurospora crassa tyrosinase and cyanide have been studied. cyanide reacts with the binuclear copper active site of the protein competitively with respect to dioxygen and displaces the metal ions. this process occurs stepwise and involves transient intermediates containing mononuclear cu(i) sites. the reaction mechanism proved to be the same as described earlier for molluscan and arthropodan hemocyanins, which share with tyrosinase the sam ...19902145978
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