PMID(sorted descending)
stearolic acid lengthens the condition period of neurospora crassa carrying the cel mutation. 19902145586
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
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
glutamine metabolism and cycling in neurospora crassa.evidence for the existence of a glutamine cycle in neurospora crassa is reviewed. through this cycle glutamine is converted into glutamate by glutamate synthase and catabolized by the glutamine transaminase-omega-amidase pathway, the products of which (2-oxoglutarate and ammonium) are the substrates for glutamate dehydrogenase-nadph, which synthesizes glutamate. in the final step ammonium is assimilated into glutamine by the action of a glutamine synthetase (gs), which is formed by two distinct ...19902145504
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
sorting pathways of mitochondrial inner membrane proteins.two distinct pathways of sorting and assembly of nuclear-encoded mitochondrial inner membrane proteins are described. in the first pathway, precursor proteins that carry amino-terminal targeting signals are initially translocated via contact sites between both mitochondrial membranes into the mitochondrial matrix. they become proteolytically processed, interact with the 60-kda heat-shock protein hsp60 in the matrix and are retranslocated to the inner membrane. the sorting of subunit 9 of neurosp ...19902145157
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
identification of the major cytoplasmic regions of the neurospora crassa plasma membrane h(+)-atpase using protein chemical techniques.the transmembrane topography of the neurospora crassa plasma membrane h(+)-atpase has been investigated using purified, reconstituted components and direct protein chemical techniques. reconstituted proteoliposomes containing h(+)-atpase molecules oriented predominantly with their cytoplasmic surface facing outward were treated with trypsin to liberate peptides present on the cytoplasmic surface of the h(+)-atpase as recently described (hennessey, j.p., jr., and scarborough, g. (1990) j. biol. c ...19902144525
nucleotide sequence of a full-length cdna coding for the mitochondrial precursor protein of the beta-subunit of f1-atpase from neurospora crassa. 19902144339
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
gene sequence and analysis of hsp30, a small heat shock protein of neurospora crassa which associates with mitochondria.hsp30 is a small heat shock protein of neurospora crassa which earlier studies suggested may associate with mitochondria during cellular heat shock. we show here that the association of hsp30 with mitochondria is reversible and that hsp30 dissociates after cells are returned to normal temperature. we sequenced the gene for hsp30 and defined its transcript by s1 nuclease analysis and cdna sequencing. the gene apparently is present in the genome as a single copy, and it contains no introns. the en ...19902144284
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
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
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
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. vi. induction kinetics of gene/point mutations, multilocus deletions and multiple-locus mutations.genetic fine-structure analysis of x-ray-induced specific-locus mutants in the ad-3 region of two-component heterokaryons of neurospora crassa has shown that gene/point mutations, multilocus deletions and multiple-locus mutations are induced. when the dose-response curves for these classes of ad-3 mutants were plotted, it was demonstrated that x-ray-induced gene/point mutations (ad-3r) increased linearly with x-ray dose and x-ray-induced multilocus deletions increased as the square of the x-ray ...19902143556
heterozygous effects of x-ray-induced specific locus mutations in the ad-3 region of neurospora crassa: implications for human genetic risk assessment. 19902143295
genetic coregulation of longevity and antioxienzymes in neurospora crassa.further analysis of a model of the biochemical genetics of cellular longevity in neurospora crassa confirms and amplifies the hypothesis that antioxienzymes and lifespans are genetically co-regulated. the model consists of seven classes of closely related strains with genetically determined median lifespans ranging from 7 to 90 days and differing by about 15-day intervals. the nuclear gene mutations age- and age+ respectively decrease and increase both lifespans and the constitutive enzyme activ ...19902143165
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
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
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
intracellular sodium content of a wall-less strain of neurospora crassa and effects of insulin: a 23na-nmr study.23na-nmr has been used to investigate some factors influencing the sodium content of a wall-less strains of neurospora crassa. the shift reagent tm(dotp)h2(nh4)3 proved useful for this purpose, while several other reagents, previously used by others, were found to be unsuitable for use with these cells. when the cells were grown, washed and resuspended in medium containing sodium (25.3 mm), the intracellular sodium concentration was calculated to be 11.9 +/- 1.4 mm. this value rose within two mi ...19902142438
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
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
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
a polypeptide of 59 kda is associated with bundles of cytoplasmic filaments in neurospora crassa.complex arrangements of filamentous structures have been isolated from vegetative cells of the fungus neurospora crassa. they were enriched by differential centrifugation and purified by permeation chromatography. the filamentous structures are made up of units of 8-10 nm diameter and were isolated in bundles of up to six to nine units. the main constituent of these structures is a polypeptide with an apparent molecular mass of 59 kda (p59nc), which represents 4-5% of the total n. crassa protein ...19902141976
assembly of nadh: ubiquinone reductase (complex i) in neurospora mitochondria. independent pathways of nuclear-encoded and mitochondrially encoded subunits.nadh:ubiquinone reductase, the respiratory chain complex i of mitochondria, consists of some 25 nuclear-encoded and seven mitochondrially encoded subunits, and contains as redox groups one fmn, probably one internal ubiquinone and at least four iron-sulphur clusters. we are studying the assembly of the enzyme in neurospora crassa. the flux of radioactivity in cells that were pulse-labelled with [35s]methionine was followed through immunoprecipitable assembly intermediates into the holoenzyme. la ...19902141652
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
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
processing of precursor proteins by plant mitochondria.precursor proteins from neurospora crassa were correctly processed by a matrix extract from vicia faba and cauliflower mitochondria. processing yielded mature protein of the same molecular mass as mature neurospora protein. the processing activity has two components. one is antigenically related to and of the same molecular mass as the processing enhancing protein of neurospora. the second component was not recognized by antibody to the matrix processing protease from neurospora mitochondria. th ...19902140932
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
duplication-induced mutation of a new neurospora gene required for acetate utilization: properties of the mutant and predicted amino acid sequence of the protein product.a cloned neurospora crassa genomic sequence, selected as preferentially transcribed when acetate was the sole carbon source, was introduced in extra copies at ectopic loci by transformation. sexual crossing of transformants yielded acetate nonutilizing mutants with methylation and restriction site changes within both the ectopic dna and the normally located gene. such changes are typical of the duplication-induced premeiotic disruption (the rip effect) first described by selker et al. (e. u. sel ...19902140429
light-induced dephosphorylation of a 33 kda protein in the wild-type strain of neurospora crassa: the regulatory mutants wc-1 and wc-2 are abnormal.light induces the dephosphorylation of a 33 kdalton protein within 8 min in the wild-type strain of neurospora crassa. the regulatory mutants, wc-1 and wc-2, have an altered pattern of phosphoproteins in darkness and also after irradiation. because the wc genes have previously been implicated in photodifferentiation (f. degli innocenti and v. e. a. russo, genetic analysis of blue light-induced responses in neurospora crassa, in h. senger (ed.), blue light effects in biological systems, springer- ...19902140412
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
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
genes responsive to the alteration of polyamine biosynthesis in neurospora crassa.wild-type neurospora crassa grown in minimal medium was exposed to -difluormethyl ornithine (dfmo), a specific inhibitor of ornithine-decarboxylase (odc-ase) activity. protein-synthesis rates impaired by dfmo were restored by the addition of spermidine. the pattern on sds-acrylamide gels displayed three newly synthesized polypeptides, p27, p31 and p99 after dfmo action in the absence of exogenous polyamine. the odc-ase mutant (spe-1) grown in spermidine-supplemented medium did not show an induce ...19902139806
chemical state of the cysteine residues in the neurospora crassa plasma membrane h(+)-atpase.the plasma membrane h(+)-atpase of neurospora crassa was treated with 5,5'-dithiobis(2-nitrobenzoate) to determine its cysteine content and with 2-nitro-5-thiosulfobenzoate to determine its cystine content. six and seven mol of thiols/mol of h(+)-atpase were detected in the 5,5'-dithiobis(2-nitrobenzoate) and 2-nitro-5-thiosulfobenzoate reactions, respectively, indicating that 6 of the 8 cysteine residues in the molecule are present as free cysteines and that 2 are present in disulfide linkage. ...19902139659
a kinetic study of the interaction between glycogen and neurospora crassa branching enzyme.the interaction of neurospora crassa branching enzyme (1,4-alpha-d-glucan:1,4-alpha-d-glucan 6-alpha-(1,4-alpha-glucano)-transferase) [ec] with substrate glycogen or amylopectin was studied by affinity electrophoresis. by this method, the dissociation constants (k) of the branching enzyme for oyster glycogen (cl-12.2, ocl-6.3) and for potato amylopectin (cl-20, ocl-12.8) were determined to be 13.3 mm and 0.355 mm, respectively. the affinity of the enzyme to the substrate glycogen increa ...19902139655
mode of action of glycogen branching enzyme from neurospora crassa.neurospora crassa branching enzyme [ec] acted on potato amylopectin or amylose to convert them to highly branched glycogen-type molecules which consisted of unit chains of six glucose units. the enzyme also acted on the amylopectin beta-limit dextrin, indicating that the enzyme acted on internal glucose chains as well as outer chains. by the combined action of n. crassa glycogen synthase [ec] and the branching enzyme, a glycogen-type molecule was formed from udp-glucose. in the ...19902139654
development of thermotolerance in neurospora crassa by heat shock and other stresses eliciting peroxidase induction.hyperthermia, cdcl2, sodium arsenite, and h2o2 led to the rapid appearance of high levels of peroxidase in neurospora crassa cultures and induced tolerance toward normally lethal temperatures in 60-h-old colonies. intracellular superoxide dismutase levels did not correlate with the development of thermotolerance.19902139653
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
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
the genetics of polyamine synthesis in neurospora mutations of the polyamine pathway of neurospora crassa fell into three categories. the majority affected ornithine decarboxylase and lay at the previously defined spe-1 locus. one mutation, jp100, defining the new spe-2 locus, eliminated s-adenosyl-methionine decarboxylase and led to putrescine accumulation. revertants of this mutation suggested that the locus encodes the enzyme. two other mutations, lv105 and jp120, defined a third locus, spe-3. strains with these mutations also accumulate ...19902139316
dna methylation and chromatin structure: a view from understanding of the function and control of dna methylation in eukaryotes has been elusive. studies of neurospora crassa have led to a model that accounts for the chromosomal distribution of methylation and suggests a basic function for dna methylation in eukaryotes.19902139257
very low atp/adp ratios with aging of the natural death senescence mutant of neurospora crassa.the natural death (nd) mutant of the fungus neurospora crassa, unlike the wild-type, undergoes an aging process, which leads to the cessation of growth. it is shown here that the atp/adp ratio of the mutant declines with age to about 3:1 whereas other strains of neurospora in the same growth medium maintain ratios of about 8 to 9:1. the decline in atp/adp ratio is not caused by the cessation of growth of the mutant. the results suggest, rather, that the cessation of growth may be caused, in part ...19902139154
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
the range of amino acids whose limitation activates general amino-acid control in neurospora crassa.several amino-acid synthetic enzymes, belonging to arginine, glutamine, leucine, lysine and phenylalanine biosynthesis, respectively, were investigated under conditions of reduced availability of any one of 16 out of the 20 amino acids represented in proteins. the enzymes showed simultaneous derepression under each condition, albeit to different degrees. derepression was abolished and the remaining basal enzyme levels reduced by mutations at the cpc-1 locus which governs general amino-acid contr ...19902138581
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
fast induction of translatable mrna by blue light in neurospora crassa wt: the wc-1 and wc-2 mutants are blind.after blue-light irradiation of neurospora crassa (wt) mycelia we observed an increase of about 13 translatable mrna species within a period of 30 min. the induction of translatable mrna species followed a specific temporal pattern which permitted the identification of four distinct classes. one of the translatable mrnas was induced in less than 2 min, while the others showed lag periods of 5, 10 or 20 min from the beginning of illumination. the white collar mutants, wc-1 and wc-2, which do not ...19902138217
determination of the inactivating alterations in two mutant alleles of the neurospora crassa cross-pathway control gene cpc-1.cpc-1 is the locus specifying what is believed to be the major trans-activating transcription factor that regulates expression of amino acid biosynthetic genes subject to cross-pathway control in neurospora crassa. mutants altered at this locus are incapable of the global increase in gene expression normally seen in response to amino acid starvation. using polymerase chain reaction methodology we have cloned and sequenced the inactive mutant allele, cpc-1 (cd15). the cpc-1 (cd15) mutation was fo ...19902138111
synaptic adjustment of inversion loops in neurospora crassa.heterozygotes for three long inversions on chromosome 1 were analyzed by serial reconstruction from electron micrographs. measurements of loop lengths at different meiotic prophase substages revealed that the homologous synapsis of the inverted region was gradually replaced by nonhomologous synapsis as loops were eliminated during pachytene. this synaptic adjustment was apparently not affected by crossovers which occurred within the 150- and 160-cm long loops.19902138110
nucleotide sequence of the gene coding for cyclophilin/peptidyl-prolyl cis-trans isomerase of neurospora crassa. 19902137907
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
nit-2, the major nitrogen regulatory gene of neurospora crassa, encodes a protein with a putative zinc finger dna-binding domain.the nitrogen regulatory circuit of neurospora crassa consists of a set of unlinked structural genes which specify various nitrogen catabolic enzymes plus control genes and metabolic effectors which regulate their expression. the positive-acting nit-2 regulatory gene is required to turn on the expression of the nitrogen catabolic enzymes during conditions of nitrogen limitation. the complete nucleotide sequence of the nit-2 gene was determined. the nit-2 mrna is 4.3 kilobases long and has a long ...19902137552
primary structure, in vitro expression and import into mitochondria of a 29/21-kda subunit of complex i from neurospora crassa.a full-length cdna clone coding for a cytoplasmically-synthesized subunit of complex i from neurospora crassa (apparent molecular mass of 29 kda) was isolated. dna sequencing revealed an open reading frame coding for a protein containing 201 amino acids. a molecular mass of 21323 da was calculated. the precursor polypeptide was efficiently expressed in vitro and imported into isolated mitochondria. it is synthesized without a cleavable signal sequence and needs a membrane potential in order to b ...19612137337
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
de novo fatty acid synthesis mediated by acyl-carrier protein in neurospora crassa mitochondria.the acyl-carrier protein (acp) in neurospora crassa mitochondria [brody, s. & mikolajczyk, s. (1988) eur. j. biochem. 173, 353-359] mediated a cerulenin-sensitive, de novo fatty acid synthesis independent of the fatty acid synthetase complex present in the cytoplasm. incubation of mitochondria with [2-14c]malonate labeled only the acp as indicated by autoradiography after sds/page. under these in vitro conditions atp was required for the initial acyl-acp formation, but further elongation require ...19902137086
direct evidence for the cytoplasmic location of the nh2- and cooh-terminal ends of the neurospora crassa plasma membrane h+-atpase.reconstituted proteoliposomes containing neurospora plasma membrane h+-atpase molecules oriented predominantly with their cytoplasmic portion facing outward have been used to determine the location of the nh2 and cooh termini of the h+-atpase relative to the lipid bilayer. treatment of the proteoliposomes with trypsin in the presence of the h+-atpase ligands mg2+, atp, and vanadate produces approximately 97-, 95-, and 88-kda truncated forms of the h+-atpase similar to those already known to resu ...19902136741
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
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
nuclease-induced dna structural changes assessed by flow cytometry with the intercalating dye propidium iodide.a flow cytometric analysis of dna structural changes induced by cleavage with nucleases was performed on isolated hela nuclei by assessing changes in stainability with the dna-specific fluorochrome propidium iodide (pi). after mild digestion with dnase i, micrococcal nuclease, or with the single-strand-specific s1 and neurospora crassa nucleases, fluorescence intensity of nuclei stained with pi increased by about 15-30% above the value of undigested control samples. no significant modifications ...19912065557
identification of molybdopterin guanine dinucleotide in formate dehydrogenase from methanobacterium formicicum.the pterin cofactor in formate dehydrogenase isolated from methanobacterium formicium is identified as molybdopterin guanine dinucleotide. the pterin, stabilized as the alkylated, dicarboxamidomethyl derivative, is shown to have absorption and chromatographic properties identical to those of the previously characterized authentic compound. treatment with nucleotide pyrophosphatase produced the expected degradation products gmp and carboxyamidomethyl molybdopterin. the molybdopterin guanine dinuc ...19912037231
sequence of the cloned pyr4 gene of trichoderma reesei and its use as a homologous selectable marker for transformation.we have cloned and sequenced the trichoderma reesei pyr4 gene encoding orotidine-5'-monophosphate decarboxylase. comparison of this sequence with that of the equivalent gene from other filamentous fungi suggests that t. reesei is closely related to cephalosporium acremonium and neurospora crassa. the cloned pyr4 gene has been used as a homologous selectable marker for transformation of t. reesei. the majority of transformants obtained with circular plasmid were mitotically unstable and contained ...19912036683
oxidation of molybdopterin in sulfite oxidase by ferricyanide. effect on electron transfer activities.the attenuation of the sulfite:cytochrome c activity of sulfite oxidase upon treatment with ferricyanide was demonstrated to be the result of oxidation of the pterin ring of the molybdenum cofactor in the enzyme. oxidation of molybdopterin (mpt) was detected in several ways. ferricyanide treatment not only abolished the ability of sulfite oxidase to serve as a source of mpt to reconstitute the aponitrate reductase in extracts of the neurospora crassa mutant nit-1 but also eliminated the ability ...19912002036
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
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
molecular cloning and characterization of alc the gene encoding allantoicase of neurospora crassa.purines can be utilized as a secondary nitrogen source by neurospora crassa during conditions of nitrogen limitation. the expression of purine catabolic enzymes is governed by the nitrogen regulatory circuit and requires induction by uric acid. the major positive-acting nitrogen regulatory gene, nit-2, turns on the expression of the purine catabolic enzymes, which may also be subject to negative regulation by a second control gene, nmr. we have cloned alc, the structural gene which encodes allan ...19901978237
behavior of the [mi-3] mutation and conversion of polymorphic mtdna markers in heterokaryons of neurospora crassa.we have examined the behavior of the [mi-3] mitochondrial mutation and two physical mtdna markers in heterokaryotic cultures of neurospora crassa. previous workers showed that a 1.2-kilobase insertion in the larger polymorphic form of ecori-5 restriction fragment is a site of high frequency and rapid unidirectional gene conversion. we have confirmed this observation and determined by dna sequence analysis that the insertion in the ecori-5 fragment corresponds precisely to an optional intron that ...19901977658
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
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
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
isolation and characterization of a neurospora crassa mutant altered in the alpha polypeptide of glutamine synthetase.we report the isolation and characterization of a neurospora crassa glutamine synthetase (gs) mutant altered in one of the two polypeptides (gs alpha) of this enzyme. we used the gln-1br8 mutant strain that synthesizes only the gs alpha monomer and lacks the gs beta monomer and selected for growth in minimal medium in the presence of alpha-methyl-dl-methionine-sr-sulfoximine (alpha-me-mso), an inhibitor of gs activity. the gs activity of the gln-1br8;alpha-me-msor strain drastically reduced its ...19901975579
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
characterization of telomere dna from neurospora crassa.the nucleotide sequence of the telomere at the right end of linkage group v (vr) in the standard or23-iv-a strain of the filamentous fungus, neurospora crassa, reveals the following features. at the chromosome terminus, tandem repeats of the hexanucleotide ttaggg are present. immediately centromere-proximal to the simple sequence repeat is a more complex element called pogo that is reiterated 5-10 times in the genomes of various neurospora strains. the element possesses several features characte ...19901971801
cloning, sequencing and expression of the schwanniomyces occidentalis nadp-dependent glutamate dehydrogenase gene.the cloned nadp-specific glutamate dehydrogenase (gdh) genes of aspergillus nidulans (gdha) and neurospora crassa (am) have been shown to hybridize under reduced stringency conditions to genomic sequences of the yeast schwanniomyces occidentalis. using 5' and 3' gene-specific probes, a unique 5.1 kb bcli restriction fragment that encompasses the entire schwanniomyces sequence has been identified. a recombinant clone bearing the unique bcli fragment has been isolated from a pool of enriched clone ...19911934128
isolation of uridine auxotrophs from trichoderma reesei and efficient transformation with the cloned ura3 and ura5 genes.uridine auxotrophs of the filamentous fungus trichoderma reesei have been selected using a positive screening procedure with 5-fluoro orotate. mutants deficient for the orotidine-5'-phosphate decarboxylase gene (ura3 mutants) and for the orotate phosphoribosyl transferase gene (ura5 mutants) have been characterized. the homologous ura3 and ura5 genes have been isolated and used to transform the auxotrophic mutants. transformation efficiency with these homologous systems is very high (greater tha ...19911913875
phylogenetic analysis of five medically important candida species as deduced on the basis of small ribosomal subunit rna sequences.the classification of species belonging to the genus candida berkhout is problematic. therefore, we have determined the small ribosomal subunit rna (srrna) sequences of the type strains of three human pathogenic candida species; candida krusei, c. lusitaniae and c. tropicalis. the srrna sequences were aligned with published eukaryotic srrna sequences and evolutionary trees were inferred using a matrix optimization method. an evolutionary tree comprising all available eukaryotic srrna sequences, ...19911865186
cysteinyl-trna synthetase is a direct descendant of the first aminoacyl-trna synthetase.the gene encoding the cysteinyl-trna synthetase of e. coli was cloned from an e. coli genomic library made in lambda 2761, a lambda vector which can integrate and which carries a chloramphenicol resistance gene. a thermosensitive cyss mutant of e. coli was lysogenised and chloramphenicol-resistant colonies able to grow at 42 degrees c were selected to isolate phages containing the wild-type cyss gene. the sequence of the gene was determined. it codes for a 461 amino-acid protein and includes the ...19911864365
the iron-sulfur clusters in the two related forms of mitochondrial nadh: ubiquinone oxidoreductase made by neurospora crassa.two related forms of the respiratory-chain complex, nadh: ubiquinone oxidoreductase (complex i) are synthesized in the mitochondria of neurospora crassa. normally growing cells make a large, piericidin-a-sensitive form, which consists of some 23 different nuclear- and 6-7 mitochondrially encoded subunits. cells grown in the presence of chloramphenicol make a small, piericidin-a-insensitive form which consists of only approximately 13 nuclear-encoded subunits. the subunits of the small form are e ...19911849820
nucleotide and derived amino acid sequences of the major porin of comamonas acidovorans and comparison of porin primary structures.the dna sequence of the gene which codes for the major outer membrane porin (omp32) of comamonas acidovorans has been determined. the structural gene encodes a precursor consisting of 351 amino acid residues with a signal peptide of 19 amino acid residues. comparisons with amino acid sequences of outer membrane proteins and porins from several other members of the class proteobacteria and of the chlamydia trachomatis porin and the neurospora crassa mitochondrial porin revealed a motif of eight r ...19911848840
regulation of the proton/electron stoichiometry of mitochondrial ubiquinol:cytochrome c reductase by the membrane potential.the electron transfer reaction catalysed by mitochondrial ubiquinol:cytochrome c reductase is linked to the outwards translocation of protons with an h+ e- stoichiometry of 1 under non-membrane potential condition. the effect of the electrical membrane potential on the h+/e- stoichiometry was investigated. the enzyme was isolated from neurospora crassa, reconstituted into phospholipid vesicles and electrical membrane potentials of various values were generated across the membranes by means of th ...19911847681
effect of activators and inhibitors on the activity of mitochondrial dna a concentration of 0.5 to 3 mmol/l, atp stimulates the activity of mitochondrial dna polymerase of neurospora crassa under the optimum reaction conditions; at higher concentrations, an inhibitory effect is observed. 4-chloromercuribenzoate (1 mmol/l), a thiol inhibitor, decreases the enzyme activity two-fold, while n-ethylmalcimide (2 mmol/l) has no effect. ethidium bromide (up to 10 mumol/l) and heparin (up to 0.4 micrograms/ml) reduce the activity by 60%. ddttp does not affect the dna polym ...19911841856
nit-4, a pathway-specific regulatory gene of neurospora crassa, encodes a protein with a putative binuclear zinc dna-binding domain.nit-4, a pathway-specific regulatory gene in the nitrogen circuit of neurospora crassa, is required for the expression of nit-3 and nit-6, the structural genes which encode nitrate and nitrite reductase, respectively. the complete nucleotide sequence of the nit-4 gene has been determined. the predicted nit4 protein contains 1,090 amino acids and appears to possess a single zn(ii)2cys6 binuclear-type zinc finger, which may mediate dna binding. site-directed mutagenesis studies demonstrated that c ...19911840634
cloning of a saccharomyces cerevisiae gene encoding a protein homologous to allantoicase of neurospora crassa. 19911839481
a preproinsulin-like pseudogene from neurospora crassa.a segment of dna was amplified from the neurospora crassa genome by the polymerase chain reaction using several oligonucleotides coding for highly conserved domains in proinsulin as primers and probe. a genomic clone corresponding to this segment was isolated and the nucleotide sequence was determined. the deduced amino acid sequence of a part of this segment bears remarkable resemblance to preproinsulin, but lacks several requirements for transcription or translation and must therefore be consi ...19911838993
identification of a sterol mutant of neurospora crassa deficient in delta 14,15-reductase activity.a mutant (erg-3) of neurospora crassa resistant to the polyene antibiotic nystatin was compared with its sensitive, wild-type parent to detect differences in sterol composition using gas chromatography-mass spectrometry. the major sterol in wild-type mycelia, comprising 80% of the total, was ergosterol. the major sterols in mutant mycelia, comprising 86% of the total, were delta 8,14-sterols. it is proposed that the nystatin-resistant strain is unable to synthesize ergosterol because it lacks de ...19911838392
sequence and structure of mtr, an amino acid transport gene of neurospora crassa.the gene product of the mtr locus of neurospora crassa is required for the transport of neutral aliphatic and aromatic amino acids via the n system. we have previously cloned three cosmids containing neurospora dna that complement the mtr-6(r) mutant allele. the cloned dnas were tightly linked to restriction fragment length polymorphisms that flank the mtr locus. a 2.9-kbp fragment from one cosmid was subcloned and found to complement the mtr-6(r) allele. here we report the sequence of the fragm ...19911838345
rip (repeat induced point mutation) as a tool in the analysis of p-450 and sterol biosynthesis in neurospora crassa. 19911838342
purification of neurospora crassa copper-metallothionein. 19911838130
stability of chitin synthetase in cell-free preparations of a wild-type strain and a 'slime' variant of neurospora crassa.chitin synthetase activity in cell-free preparations from a wild-type strain and a 'slime' variant of neurospora crassa was monitored over many days in samples stored at 0 degrees c. total activity in whole-cell-free extracts and low-speed supernatants from both organisms was very unstable, losing more than 90% of the initial activity on storage at 0 degrees c for 96 h. chitin synthetase detection was not masked by chitinase activity present in the preparations. gel-filtration chromatography of ...19911838089
an electroporation-based system for high-efficiency transformation of germinated conidia of filamentous fungi.a rapid and efficient electroporation procedure has been developed for transformation of germinating conidia of filamentous fungi. pretreatment of conidial preparations with a cell wall weakening agent, such as beta-glucuronidase, was found to be essential for successful transformation. using the qa-2+ gene of neurospora crassa, encoding the catabolic dehydroquinase, as a selectable marker with a double-mutant host strain, auxotrophic for aromatic amino acids, integration of the plasmid was obse ...19911838030
amplitude model for the effects of mutations and temperature on period and phase resetting of the neurospora circadian oscillator.this paper analyzes published and unpublished data on phase resetting of the circadian oscillator in the fungus neurospora crassa and demonstrates a correlation between period and resetting behavior in several mutants with altered periods: as the period increases, the apparent sensitivity to resetting by light and by cycloheximide decreases. sensitivity to resetting by temperature pulses may also decrease. we suggest that these mutations affect the amplitude of the oscillator and that a change i ...19911837742
temperature compensation of the circadian rhythm in neurospora crassa: comments on the vicinal water hypothesis. 19911837741
photoregulation of the albino-3 gene in neurospora this paper we describe the light-regulated expression of albino-3 (al-3), a carotenoid biosynthetic gene of neurospora crassa, in the wild-type strain. our results suggest that the al-3 gene expression is regulated by the transcriptional activation of the gene and the low stability of its mrna. the activation of the al-3 gene does not require protein synthesis to occur. the kinetic analysis of the al-3 mrna reveals that the gene is transiently expressed even in continuous light, suggesting th ...19911837560
molecular cloning, characterization and analysis of the regulation of the aro2 gene, encoding chorismate synthase, of saccharomyces cerevisiae.we describe here the cloning, characterization and analysis of the regulation of the aro2 gene of saccharomyces cerevisiae, the first reported study of a eukaryotic gene encoding chorismate synthase (e.c. the gene contains an orf of 1128 bp, encoding a protein with a calculated molecular mass of 40.8 kda. aro2 is regulated under the 'general control system' for amino acid biosynthesis by the transcriptional activator gcn4 which binds in vitro at three sites within the aro2 promoter. th ...19911837329
genetics and molecular biology of neurospora crassa. 19911837201
blue light induction of conidiation-specific genes in neurospora crassa.the con genes of neurospora crassa are preferentially expressed during a developmental process known as conidiation. we present evidence indicating that transcription of con-5 and con-10 is also stimulated by blue light. transcription of these genes was not photoinducible in wc-1 and wc-2 mutant strains. the response of con-5 and con-10 to blue light was similar to that of al-1 and al-2, genes involved in carotenoid biosynthesis, and bli-3 and bli-4, blue light inducible genes.19911837079
coordinate expression of ribosomal protein genes in neurospora crassa and identification of conserved upstream sequences.the relative levels of rrnas and ribosomal proteins are coordinately regulated by growth rate and carbon nutrition in neurospora crassa. however, little is known about the mechanisms involved. to investigate the transcriptional regulation of ribosomal protein genes in n. crassa, we cloned and sequenced a ribosomal protein gene (crp-3). the inferred crp-3 protein sequence shares 89% and 83% homology at its n-terminus with the yeast rp51 and the human s17 ribosomal proteins respectively. the crp-3 ...19911836561
efficient dna pairing in a neurospora mutant defective in chromosome pairing.a neurospora crassa mutation, mei-2, affecting recombination and pairing of homologous chromosomes during meiosis, was characterized for its effect on repeat-induced point mutation (rip). we found that rip, which depends on recognition of dna sequence homology, is not inhibited by mei-2, suggesting that the defect in chromosome pairing of this mutant is not due to a defect in dna pairing and that dna pairing is not dependent on chromosome pairing.19911836526
mei-2, a mutagen-sensitive mutant of neurospora defective in chromosome pairing and meiotic recombination.a neurospora crassa mutation, mei-2, affecting meiosis and mutagen sensitivity, was characterized for its effect on meiotic recombination and chromosome pairing. results from homozygous mei-2 crosses involving distant markers on the same chromosome demonstrated a drastic reduction in meiotic recombination. however, mitotic recombination continued to occur. cytological observations indicated that pairing of homologous chromosomes in zygotene was greatly reduced or absent, resulting in aberrant se ...19911836525
chitin synthase 1 plays a major role in cell wall biogenesis in neurospora filamentous fungi, chitin is a structural component of morphologically distinct structures assembled during various phases of growth and development. to investigate the role of chitin synthase in cell wall biogenesis in neurospora crassa, we cloned a chitin synthase structural gene and examined the consequences of its inactivation. using degenerate oligonucleotide mixtures designed on the basis of conserved sequences of the saccharomyces cerevisiae chs1 and chs2 polypeptides, a dna fragment e ...19911836444
Displaying items 5001 - 5100 of 5889