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nitrogen catabolite repression in yeasts and filamentous fungi. 19852869649
isolation and characterization of the aspergillus niger trpc gene.the aspergillus niger trpc gene was isolated by complementation experiments with an escherichia coli trpc mutant. plasmid dna containing the a. niger trpc gene transforms an aspergillus nidulans mutant strain, defective in all three enzymatic activities of the trpc gene, to trp+, indicating the presence of a complete and functional trpc gene. southern blot analysis of dna from these trp+ transformants showed that plasmid dna was present but that this dna was not integrated at the site of the chr ...19852936650
cloning and characterization of the ethanol utilization regulon in aspergillus nidulans.in aspergillus nidulans alcohol dehydrogenase (adh) i and aldehyde dehydrogenase (alddh) are co-inducible by acetaldehyde (pateman et al., 1983; sealy-lewis and lockington, 1984) and subject to carbon catabolite repression. the structural genes alca and alda are unlinked, but alca is closely linked to the positive control gene alcr. we have obtained cdna clones of alca and alda and genomic clones comprising alca and alcr. the location of these genes in a genomic clone carrying a 13-kb insert was ...19853158573
spontaneous ir duplications generated at mitosis in aspergillus nidulans: further evidence of a preferential site of transposed attachment.a radiation-induced translocation, t(iir----iiil), has been shown to be nonreciprocal and to have most of iir, including its terminus, attached uninverted to the terminus of iiil.--progeny with the iir segment in duplicate, obtained from crosses of t(iir----iiil) to strains with a standard genome, were unstable at mitosis; like earlier duplication strains, they suffered deletions from either duplicate segment. frequent mitotic crossing over occurred between the duplicate iir segments so that, fo ...19853891510
transformation of aspergillus niger by the amds gene of aspergillus nidulans.aspergillus niger grows poorly on acetamide as a nitrogen or carbon source and lacks sequences detectably homologous to the amds gene encoding the acetamidase of aspergillus nidulans. we have taken advantage of these observations to develop a transformation system for a. niger using the amds gene as a dominant heterologous marker for selecting transformants on the basis of acetamide utilization. transformants varied in their ability to grow on amide media and the number of integrated copies of t ...19853894007
a conductimetric method for assaying asparaginase activity in aspergillus nidulans.aspergillus nidulans asparaginase activity may be assayed conductimetrically. the method is based on the increase of conductivity which is due to the production of ammonia and/or aspartate in a reaction mixture containing a. nidulans cell-free extract and asparagine or aspartate hydroxamate. this conductivity is linear with time and enzyme concentration and it follows michaelis kinetics. conductimetric activity was not detectable in mutants lacking asparaginase activity.19853896790
isolation and characterization of cold-sensitive mutations at the bena, beta-tubulin, locus of aspergillus nidulans.we have isolated large numbers of conditionally lethal beta-tubulin mutations to provide raw material for analyzing the structure and function of beta tubulin and of microtubules. we have isolated such mutations as intragenic suppressors of bena33, a heat-sensitive (hs-) beta-tubulin mutation of aspergillus nidulans. among over 2,600 revertants isolated, 126 were cold-sensitive (cs-). in 41 of 78 cs- revertants analyzed, cold sensitivity and reversion from hs- to hs+ were due to mutations linked ...19853903435
cloning and characterization of the three enzyme structural genes qutb, qutc and qute from the quinic acid utilization gene cluster in aspergillus nidulans.heterologous dna probes from the quinic acid gene cluster (qa) in neurospora crassa (schweizer 1981) have been used to isolate the corresponding gene cluster (qut) from aspergillus nidulans cloned in a phage lambda vector. n. crassa probes for each of the three enzyme structural genes in the cluster have been used to identify the corresponding genes within the a. nidulans cloned dna. the three genes are in the same relative sequence [dehydrogenase (1), qa-3 = qutb; dehydratase (3), qa-4 = qutc; ...19853916726
gene amplification in aspergillus nidulans by transformation with vectors containing the amds gene.conidial protoplasts of an a. nidulans amds deletion strain (mh1277) have been transformed to the amds+ phenotype with a plasmid carrying the wild type gene (p3sr2). optimalisation of transformation and plating conditions now has resulted in frequencies of 300-400 transformants per microgram of dna. analysis of dna from amds+ transformants of mh1277 showed that transformation had occurred by integration of vector dna sequences into the genome. in virtually all these transformants multiple copies ...19853916728
identification of the acia gene controlled by the amda regulatory gene in aspergillus nidulans.the amda gene is one of a number of transacting regulatory genes controlling expression of the amds gene in a. nidulans. a polypeptide of approximately 42,000 molecular weight has been found to be synthesized constitutively in amda mutant strains and to be acetate inducible. a lambda clone containing a gene, called acia, coding for this polypeptide has been isolated using differential screening with cdna probes. two acetate inducible rna species have been identified by probing northern blots wit ...19853916805
dependence of nitrate utilization upon active co2 fixation in anacystis nidulans: a regulatory aspect of the interaction between photosynthetic carbon and nitrogen metabolism.specific inhibition of photosynthetic co2 fixation in anacystis nidulans cells by d,l-glyceraldehyde resulted in the simultaneous inhibition of nitrate utilization, indicating a dependence of the latter process upon the provision of co2-fixation products. this dependence was lost in cells treated with l-methionine-d,l-sulfoximine or azaserine, effective inhibitors of ammonium assimilation. in these cells, nitrate uptake could proceed at rates similar to those in control cells even if co2 fixatio ...19853919645
dna metabolism during infection of anacystis nidulans by cyanophage as-1. vi. effect of hydroxyurea and nalidixic acid on the development of cyanophage as-1.the use of the dna inhibitors hydroxyurea (hu) and nalidixic acid (nal) to elucidate patterns of dna metabolism in as-1 infected a. nidulans have led to several conclusions. first, hu and nal at concentrations of 500 and 100 micrograms/ml, respectively, inhibited dna synthesis in synchronized a. nidulans. protein and chlorophyll synthesis remained essentially unchanged as did turbidity increases. second, the complete burst size of the cyanophage as-1 was severely affected by hu and nal treatment ...19853938513
transformation of aspergillus nidulans. 19853939985
systems and results of tests for chemical induction of mitotic malsegregation and aneuploidy in aspergillus nidulans.in aspergillus several types of test systems have been developed for detection of chemicals which induce aneuploidy and/or malsegregation of chromosomes. results from 23 papers were reviewed in which numerical data for 42 chemicals had been reported. the test systems fall into two groups. one group includes all purely genetic tests that detect euploid mitotic segregants from heterozygous diploids and identify these either as products of malsegregation of chromosomes or as products of crossing-ov ...19863510377
pyruvate carboxylase from saccharomyces cerevisiae. quaternary structure, effects of allosteric ligands and binding of avidin.the quaternary structure of pyruvate carboxylase purified from saccharomyces cerevisiae was investigated by electron microscopic examination of negatively stained samples. in the most frequently observed projection form four intensity maxima were arranged at the corners of a rhombus; a cleft along the longitudinal axis of individual protomers could often be discerned. the observation of occasional triangular and dual-intensity projections and the interconversion of all three projection forms in ...19863514213
the fatty acid composition of the conidia and mycelia of the fungus aspergillus nidulans.the total fatty acids were characterized from conidia, exponential phase, and stationary phase aspergillus nidulans. several quantitative and qualitative variations were observed. most notable was the approximately 15-fold increase in linolenate observed during the 1st day of incubation and its subsequent total disappearance by day 4.19863516353
functional assembly in vitro of phycobilisomes with isolated photosystem ii particles of eukaryotic chloroplasts.phycobiliproteins obtained by dissociation of phycobilisomes were reassociated in vitro with intact thylakoids or isolated photosystems i and ii preparations obtained from cyanophytes (prokaryotes) or green algae (eukaryotes) to form bound phycobilisome complexes. energy transfer from fremyella diplosiphon phycobiliproteins to chlorophyll a of reaction centers i and ii was measured in: complexes containing intact thylakoids of the cyanophytes f. diplosiphon or anacystis nidulans and the eukaryot ...19863528156
saccharomyces cerevisiae centromere cen11 does not induce chromosome instability when integrated into the aspergillus nidulans genome.we constructed aspergillus nidulans transformation plasmids containing the a. nidulans argb+ gene and either containing or lacking centromeric dna from saccharomyces cerevisiae chromosome xi (cen11). the plasmids transformed an argb aspergillus strain to arginine independence at indistinguishable frequencies. stable haploid transformants were obtained with both plasmids, and strains were identified in which the plasmids had integrated into chromosome iii by homologous recombination at the argb l ...19863540597
primary structure of mucor miehei aspartyl protease: evidence for a zymogen intermediate.the gene encoding the aspartyl protease of the filamentous fungus mucor miehei has been cloned in escherichia coli and the dna sequenced. the deduced primary translation product contains an n-terminal region of 69 amino acid (aa) residues not present in the mature protein. by analogy to the evolutionarily related mammalian gastric aspartyl proteases it is inferred that the primary secreted product is a zymogen containing a 47-aa propeptide. this propeptide is presumably removed in the later step ...19863549462
genotoxicity of hexachlorobenzene and other chlorinated benzenes.hexachlorobenzene (hcb) and other chlorinated benzenes have had only limited mutagenicity evaluation but tests have shown a general lack of evidence for mutagenicity. bacterial reverse mutation studies have been typically negative and only a few studies on cultured mammalian cells have been published. recent reports indicate that hcb does not induce sister chromatid exchange or dna-strand breakage in vitro. a single report of hcb-induced reverse mutation in yeast is suspect due to the failure to ...19863596730
a case of guttural pouch mycosis in a horse.a case of guttural pouch mycosis in an 11-year-old horse is described. the fungus isolated was identified as emericella nidulans. housing under bad hygienic conditions without ventilation for three years might have been a predisposing factor.19863725585
isolation and nucleotide sequence analysis of the ferredoxin i gene from the cyanobacterium anacystis nidulans r2.two mixed oligonucleotide probes derived from conserved regions of the synechocystis sp. strain pcc 6714 ferredoxin amino acid sequence were utilized to isolate an anacystis nidulans r2 clone containing the ferredoxin i gene. nucleotide sequence analysis revealed a 297-base-pair (bp) open reading frame with a deduced amino acid sequence having high homology to other cyanobacterial ferredoxins. assuming proteolytic cleavage of the initial methionine residue, the molecular weight of the mature a. ...19863096975
exploiting classical genetics to clone a eukaryotic regulatory gene. 19863153577
heat shock phenomena in aspergillus nidulans. i. the effect of heat on mycelial protein synthesis.heat shock was found to induce characteristic changes in the pattern of protein synthesis in aspergillus nidulans as analysed by sds-polyacrylamide gel electrophoresis. six to seven new bands were found to show increased incorporation to 35s-methionine at 43 degrees c compared to 37 degrees c, the standard temperature for this organism. the heat shock response of five different strains of a. nidulans was examined. this comparative study showed that these strains (haploids and diploids) show exac ...19863329035
aspergillus nidulans 5s rrna genes and pseudogenes.the sequence of four aspergillus nidulans 5s rrna genes and of two pseudogenes has been determined. a conserved sequence about 100 bp upstream of the 5s rrna coding sequences has been found in three genes and one pseudogene. the two pseudogenes correspond to the 5' half of the 5s rrna coding sequence and their 3' flanking sequences which are not homologous to 5s rrna are strongly conserved.19863327606
genetic and molecular characterization of argb+ transformants of aspergillus nidulans.thirty-three argb- to argb+ transformants of aspergillus nidulans have been subjected to genetic and molecular analysis. two showed high levels of mitotic instability although it is suggested that this is a consequence of heterokaryosis rather than instability of the transformation event. most transformants resulted from the integration of the transforming dna in tandem with the chromosomal argb locus. the maximum number of inserted sequences was two, to generate three copies of the argb locus. ...19863327613
controlled gene expression utilising lambda phage regulatory signals in a cyanobacterium host.this study presents plasmid systems that utilize regulatory signals of bacteriophage lambda to accomplish regulated expression of cloned genes in an a. nidulans r2 derivative strain. an operator-promoter region and the temperature-sensitive repressor gene ci857 of bacteriophage lambda were employed. linked to a cyanobacterial replicon, the plasmid vectors efficiently transformed anacystis and were stably maintained within this host. the cat structural gene, encoding chloramphenicol acetyltransfe ...19863018433
heterologous insertion of transforming dna and generation of new deletions associated with transformation in aspergillus nidulans.the analysis of four transformants for the proline catabolism (prn) gene cluster of aspergillus nidulans is reported. using a combination of traditional genetic methodology and southern hybridisation we have shown that in two cases multiple copies of the transforming plasmid have been integrated into linkage groups other than vii, which contains the prn cluster. in the other two cases integration of the plasmid has probably occurred homologously. the phenotype of these transformants is broadly c ...19863018435
variation in the polypeptide composition of phycobilisomes from anacystis nidulans and three pigment mutants.phycobilisomes, light harvesting antenna pigment systems, were studied from anacystis nidulans wild type and from several spontaneous pigment mutants selected for improved growth in far-red light (>650 nm). this is the first characterization and description of polypeptide composition of phycobilisomes from spontaneous mutants (not chemically induced) of a. nidulans. the mutants had significant changes in the phycobiliprotein content relative to chlorophyll (chl). two phycobiliproteins, c-phycocy ...198624443211
a cloned tryptophan-synthesis gene from the ascomycete cochliobolus heterostrophus functions in escherichia coli, yeast and aspergillus nidulans.a gene (trp1) in the tryptophan biosynthetic pathway of the fungal plant pathogen cochliobolus heterostrophus was isolated by complementation of an escherichia coli trpf mutant which lacked phosphoribosylanthranilate isomerase (prai) activity. the cloned gene also complemented an e. coli trpc mutant lacking indoleglycerolphosphate synthase (igps) activity, a yeast trp1 mutant missing prai activity and an aspergillus nidulans trpc mutant. it functioned in e. coli and a. nidulans without apparent ...19862941339
the atp synthase subunit 9 gene of aspergillus nidulans: sequence and transcription.we have determined the nucleotide sequence of the aspergillus nidulans nuclear gene olic31, which encodes subunit 9 of mitochondrial atp synthase. the open reading frame contains no introns and specifies a predicted protein of 143 amino acids comprising a pre-sequence of 62 residues and a mature protein of 81 residues. the amino acid homology with the equivalent neurospora crassa protein is 50% for the pre-sequence and 80% for the mature protein. a comparison with this and other imported mitocho ...19862880279
structural genes for phosphatases in aspergillus nidulans. 19863011590
biosynthesis of a 42-kd polypeptide in the cytoplasmic membrane of the cyanobacterium anacystis nidulans strain r2 during adaptation to low co(2) concentration.when cells of anacystis nidulans strain r2 grown under high co(2) conditions (3%) were transferred to low co(2) conditions (0.05%), their ability to accumulate inorganic carbon (c(i)) increased up to 8 times. cytoplasmic membranes (plasmalemma) isolated at various stages of low co(2) adaptation were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. there was a marked increase of a 42-kilodalton polypeptide in the cytoplasmic membrane during adaptation; a linear relationship ...198616664655
the subunit i of the respiratory-chain nadh dehydrogenase from cephalosporium acremonium: the evolution of a mitochondrial gene.a cephalosporium acremonium mitochondrial gene equivalent to human urf1 has been identified. the primary structure of the protein is highly homologous to its human (39%) and a. nidulans (66%) counterparts. hydrophobicity profiles and predicted secondary structures are also very similar suggesting that this gene codes for the subunit i of the respiratory-chain nadh dehydrogenase. the nucleotide sequence of the gene, 70% homologous to the a. nidulans one, presents a high at content (72%) and this ...19863447737
mitotic crossing over in chromosome i disomics of aspergillus nidulans.the frequency and pattern of homologous recombination in chromosome i disomics of aspergillus nidulans is presented. approximately 6% of randomly selected haploid breakdown sectors are recombinant. most of these arise from double exchange events, one of which is located in the centromere region, the other distal on the left arm. other marked regions are rarely involved in a recombination event. reciprocal genotypes arise in approximately equal frequencies indicating that exchange results in reci ...19863520237
tests which distinguish induced crossing-over and aneuploidy from secondary segregation in aspergillus treated with chloral hydrate or gamma-rays.a system of tests with the ascomycete aspergillus nidulans was devised that can detect 3 primary effects of genotoxic agents: (1) increases in mitotic crossing-over; (2) induced aneuploidy; and (3) clastogenic effects which cause chromosomal imbalance. conidia of a new diploid tester strain, heterozygous for 4 recessive markers which alter conidial color, are treated and plated onto nonselective media. in cases of induced crossing-over, large color segments are found in normal green colonies, fr ...19863520302
characterization of aspergillus nidulans mutants in carbon metabolism isolated after d-galacturonate enrichment.a selective method for the isolation of aspergillus nidulans mutants defective in the pyruvate dehydrogenase complex was devised. the essential steps in the procedure were a mutagenic treatment of conidia with x-rays to about 50% survival, followed by filtration enrichment in minimal medium with d-galacturonate as sole carbon source, and rescue on complete medium with acetate. the mutants thus isolated were phenotypically characterized on the basis of growth tests, and different genotypes were a ...19863534135
osmotic adjustment in the filamentous fungus aspergillus nidulans.aspergillus nidulans was shown to be xerotolerant, with optimal radial growth on basal medium amended with 0.5 m nacl (osmotic potential [psi s] of medium, -3 mpa), 50% optimal growth on medium amended with 1.6 m nacl (psi s of medium, -8.7 mpa), and little growth on medium amended with 3.4 m nacl (psi s of medium, -21 mpa). the intracellular content of soluble carbohydrates and of selected cations was measured after growth on basal medium, on this medium osmotically amended with nacl, kcl, gluc ...19863536874
isolation of mip (microtubule-interacting protein) mutations of aspergillus nidulans.we identified four mutations in two previously undescribed loci involved in microtubule function in aspergillus nidulans as extragenic suppressors of bena33, a heat-sensitive beta-tubulin mutation. three of the four mutations map to a locus closely linked to ribob on linkage group viii; we designated this locus mipa (for microtubule-interacting protein). we were not able to map the remaining suppressor because of chromosomal rearrangements. however, since it recombines with ribob at a significan ...19863537728
cloning of the regulatory gene area mediating nitrogen metabolite repression in aspergillus nidulans.the area gene, which mediates nitrogen metabolite repression in the fungus aspergillus nidulans, lies sufficiently close to a telomere that no indispensable gene can be distal to it. we were able therefore to exploit the existence of a near terminal pericentric inversion to devise a method for cloning area plus the region beyond it towards the telomere. in crosses heterozygous for this inversion a class of duplication-deficient progeny lacking area and the region centromere-distal to it is obtai ...19863013617
expression of the aspergillus nidulans argb gene in escherichia coli.the aspergillus nidulans argb gene coding for ornithine carbamoyltransferase (otcase) is not expressed in escherichia coli. however, e. coli otcase-deficient strains transformed with plasmids carrying the argb gene from a. nidulans reverted to prototrophy at a high frequency. in these derivatives the argb gene became functional due to dna rearrangements upstream of the coding sequence. two types of rearrangement were characterized. one was identified as an insertion of is2. the second was a dele ...19863027235
organization of the genes for protein synthesis elongation factors tu and g in the cyanobacterium anacystis nidulans.the genes for protein synthesis elongation factors tu and g were cloned from the cyanobacterium anacystis nidulans. the locations of these genes were mapped within the cloned dna fragment by hybridization with escherichia coli probes. the organization of the cloned fragment and the dna flanking it in the a. nidulans chromosome was also determined. the elongation factor tu and g genes are adjacent to one another and in the same 5'-to-3' orientation. in contrast to other gram-negative bacteria, a. ...19863082860
transformation of the cyanobacterium anacystis nidulans 6301 with the escherichia coli plasmid pbr322.anacystis nidulans 6301 has been transformed in the light to ampicillin resistance with the plasmid pbr322. permeaplasts prepared by 2-hr treatment of cells with lysozyme and edta are transformed with a 50-fold higher efficiency than that observed for cells. beta-lactamase is present in a. nidulans transformed either with pbr322 or the plasmid pch1 as evidenced by hydrolysis of the beta-lactam ring of nitrocefin in extracts of transformants. beta-lactamase also can be immunoprecipitated from ext ...19863085098
isolation and identification of the aspergillus nidulans gdha gene encoding nadp-linked glutamate dehydrogenase.the neurospora crassa am gene was used as a heterologous probe to identify clones from two independently constructed aspergillus nidulans gene libraries. these clones have a common hindiii 1.85 kb fragment. this a. nidulans nucleotide stretch hybridises to a n. crassa 2.7 kb bamhi fragment of wild type dna but not to a co-migrating fragment from the dna of the n. crassa am132 deletion mutant. one a. nidulans clone was shown to complement the n. crasse am132 deletion strain. the n. crassa transfo ...19862834076
sequence analysis and transformation by the catabolic 3-dehydroquinase (qute) gene from aspergillus nidulans.the induction of catabolic 3-dehydroquinase by quinic acid in aspergillus nidulans has been shown to involve transcriptional control and yields a single major 0.8 kb mrna. the nucleotide sequence of the catabolic 3-dehydroquinase qute gene has been determined and contains a single uninterrupted open reading frame of 462 bases encoding a 16,505 da protein of 153 residues. comparison with the corresponding qa2 gene of neurospora crassa reveals the absence of 75 nucleotides encoding 25 amino acids ...19862949740
tallysomycin-induced mitotic aneuploidy and point mutations in aspergillus nidulans.tallysomycin is an antibiotic compound structurally related to bleomycin, and like bleomycins and phleomycins also shows antitumour activity. we have investigated the genetic activity of tallysomycin in the ascomycete aspergillus nidulans for malsegregation of chromosomes at mitosis and for point mutations. we found that the antibiotic at very low concentrations from 0.025 to 0.2 micrograms/ml had an inhibitory effect on colonial growth of up to 50% and it increased the number of mitotic malsegr ...19862457783
the isolation and nucleotide sequence of the complex arom locus of aspergillus nidulans.the arom locus of a. nidulans, which governs five consecutive steps in pre-chorismate aromatic amino acid biosynthesis, has been cloned in a bacteriophage vector. the nucleotide sequence of the locus reveals a single, open reading-frame of 4,812 base-pairs, apparently without introns. an internal segment of the a. nidulans arom sequence has extensive homology with the e. coli aroa gene that encodes the 5-enolpyruvylshikimate 3-phosphate synthase.19863515316
nucleotide sequence of the triosephosphate isomerase gene from aspergillus nidulans: implications for a differential loss of introns.a functional cdna from aspergillus nidulans encoding triosephosphate isomerase (tpi) was isolated by its ability to complement a tpi1 mutation in saccharomyces cerevisiae. this cdna was used to obtain the corresponding gene, tpia. alignment of the cdna and genomic dna nucleotide sequences indicated that tpia contains five introns. the intron positions in the tpia gene were compared with those in the tpi genes of human, chicken, and maize. one intron is present at an identical position in all fou ...19863521890
a system for the analysis of expression signals in aspergillus.to analyse gene expression signals in aspergillus we have constructed a set of integration vectors each of which contains in front of the escherichia coli 'lacz gene a unique bamhi site in one of the three possible translational reading frames and the a. nidulans argb gene as a selection marker. the vectors allow in-phase translational fusion of any gene to 'lacz. after transformation of an a. nidulans argb strain, the vectors integrate with a high percentage at the argb locus of the genome, as ...19863549463
the amds gene of aspergillus nidulans: control by multiple regulatory signals. 19863551935
effect of the bnca gene on the instability of aspergillus nidulans. 19863552882
mitotic recombination in stable and unstable chromosome iii disomics of aspergillus nidulans.approximately 2% of the haploid breakdown sectors of heterozygous chromosome iii disomics of aspergillus nidulans are the result of recombination between the homologous chromosomes. the exchanges are concentrated between the two mutations spanning the centromere. comparisons are made between disomics hemizygous for the sodiii a1 mutation (upshall et al. 1979) which are stable when grown at 37 degrees c, and disomics carrying the wild type allele of the sodiii a1 locus, which are unstable under a ...19863327614
behaviour of recombinant plasmids in aspergillus nidulans: structure and stability.a pyrg- aspergillus strain was transformed with plasmid pdjb-1, derived from pbr325 by insertion of the neurospora crassa pyr4 gene (orotidine 5'-phosphate carboxylase), giving mitotically unstable transformants. aspergillus dna which acted as an "autonomously replicating sequence" (ars) in yeast was inserted into pdjb-1 and the resulting construct, pdjb12.1, gave mitotically stable transformants when introduced into aspergillus. transformants obtained with pdjb-1 and pdjb12.1 gave few pyr- prog ...19863329034
regulation of gene expression by ph of the growth medium in aspergillus nidulans.in the fungus aspergillus nidulans the levels of a number of enzymes whose location is at least in part extracellular (e.g. acid phosphatase, alkaline phosphatase, phosphodiesterase) and of certain permeases (e.g. that for gamma-amino-n-butyrate) are controlled by the ph of the growth medium. for example, at acidic ph, levels of acid phosphatase are high and those of alkaline phosphatase are low whereas at alkaline ph the reverse is true. mutations in five genes, pala, b, c, e and f, mimic the e ...19863016485
molecular analysis of the argb gene of aspergillus nidulans.the transcriptional organization and sequence of the aspergillus nidulans argb gene, encoding ornithine carbamoyl transferase (octase; e.c. 2.1.3.3.), was determined. transcription of the gene begins within a methionine-initiated open translation reading frame, indicating that a second methionine codon of the open reading frame is used for translation initiation. the predicted length of the octase precursor peptide is 359 amino acids, and it contains a highly basic amino terminus that is probabl ...19863020372
grouping of aspergillus species with exoantigens.ninety-two slant extracts prepared from 2-week-old cultures of seven aspergillus groups, nonsporulating "albino-type" a.fumigatus, blastomyces dermatitidis, histoplasma capsulatum, 3 penicillium spp., 2 pseudallescheria spp., 3 paecilomyces spp., and acremonium sp., were analyzed concurrently against antisera to a. fumigatus, a. flavus, a. nidulans, a. niger, and a. terreus. the extract of each of the aforementioned five pathogenic aspergillus spp. produced 2-11 specific antigen-antibody complex ...19863086014
characterization of dna uptake by the cyanobacterium anacystis nidulans.the binding and uptake of nick-translated 32p-labeled pbr322 by anacystis nidulans 6301 have been characterized. both processes were considerably enhanced in permeaplasts compared to cells. the breakdown of labeled dna was not correlated with binding or uptake by permeaplasts or cells. uptake of dna by permeaplasts was unaffected by: mg2+ or ca2+, light, or inhibitors of photophosphorylation such as valinomycin or gramicidin d in the presence or absence of nh4cl. atp at 2.5-10 mm inhibited both ...19863093820
endogenous energy supply to the plasma membrane of dark aerobic cyanobacterium anacystis nidulans: atpase-independent efflux of h+ and na+ from respiring cells.the ejection of protons from oxygen-pulsed cells and the gradients of na+ concentration (na+o/na+i at 150 mm external nacl) and proton electrochemical potential (delta mu h+) across the plasma membrane of anacystis nidulans were studied in response to dark endogenous energy supply. saturating concentrations of the f0f1-atpase inhibitors dicyclohexylcarbodiimide (f0) and 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (f1) eliminated oxidative phosphorylation and lowered the atp level from 2.6 +/- 0.15 to ...19863010878
phosphatase regulation in aspergillus nidulans: responses to nutritional starvation. 19863011591
cloning of the arg-12 gene of neurospora crassa and regulation of its transcript via cross-pathway amino acid control.the arg-12 locus of neurospora crassa encodes ornithine carbamoyl transferase, which is one of many amino acid synthetic enzymes whose activity is regulated through cross-pathway (or general) amino acid control. we report here the use of probes derived from the functionally equivalent arg-b gene of aspergillus nidulans to identify and clone a 10 kb neurospora dna fragment carrying the arg-12 gene. short neurospora dna probes derived from this fragment were used to identify a 1.5 kb polya+ transc ...19863012277
localization of alkaline phosphatase activity at microbody membranes of neurospora crassa and aspergillus nidulans.hyphal cells of neurospora crassa and aspergillus nidulans, grown in sabouraud glucose broth or in a defined medium with xanthine or its catabolites as the nitrogen source, contained single membrane-bound organelles cytochemically identified as microbodies. modified gomori procedures at the ultrastructural level revealed putative alkaline phosphatase activity sites in thin sections of cells of both species of fungi. microbody membranes displayed electron opaque deposits (lead phosphate) which we ...19862948778
the watermelon mitochondrial urf-1 gene: evidence for a complex structure.we have cloned and sequenced a fragment of watermelon mitochondrial dna (mtdna) which contains a gene homologous to mitochondrial urf-1 (unidentified reading frame-1) of vertebrates, drosophila yakuba and aspergillus nidulans. urf-1 is thought to encode a component of the respiratory chain nadh dehydrogenase. two coding regions in the watermelon gene are separated by approximately 1,450 bp of untranslatable dna. these two exons encode the central portions of urf-1, and are highly conserved. we p ...19863447741
genetic analysis of dna repair in aspergillus: evidence for different types of mms-sensitive hyperrec mutants.to identify genes which affect dna repair and possibly recombination in aspergillus nidulans, mutants hypersensitive to methyl methanesulphonate (mms) were induced with ultraviolet light (uv) or gamma-rays. about half of them contained associated translocations and many were hypersensitive to uv and/or defective in meiosis. two are alleles of the known uvsb gene while most others define new genes. in addition, among available uvs mutants many were found to be mms-sensitive. some of the various u ...19863523224
genetic and functional analysis of beta tubulin in aspergillus nidulans. 19863524367
a comparative study on selected chemical carcinogens for chromosome malsegregation, mitotic crossing-over and forward mutation induction in aspergillus nidulans.10 "false negative" chemical carcinogens, i.e. ineffective in bacterial mutagenicity assays, were thoroughly investigated for their genotoxic activity in the mould aspergillus nidulans. forward mutations (methionine suppressors), mitotic crossing-over and chromosome malsegregation were the end-points scored. positive results were obtained in tests for the induction of mitotic segregation with benzene, ethylenethiourea and urethane, which increased the frequency of abnormal presumptive aneuploid ...19863531838
transcription and processing signals in the 3-phosphoglycerate kinase (pgk) gene from aspergillus nidulans.the 3-phosphoglycerate kinase gene from aspergillus nidulans contains two 57-bp introns and codes for a 421-amino acid (aa) protein with considerable homology to the saccharomyces cerevisiae (68%) and mammalian (64%) proteins. almost total conservation is found in aspergillus of residues thought to be important to the structure and function of the yeast enzyme, and the introns fall between coding sequences for postulated structures in the n-domain. the strong codon preference found is more simil ...19863533726
genetic analysis of aspergillus nidulans amds+ transformants.to correlate the genetic background of the aspergillus nidulans amds deletion strain mh1277 with the integrational behaviour of transforming vectors, classical genetic methods were used to construct amds- strains in which whole chromosomes had been exchanged with those of a master strain. progeny strains were transformed to the amds+ phenotype with vector p3sr2. from southern analysis it was concluded that transformants from all constructions contained tandemly repeated, multiple copy inserts of ...19863543620
intracellular localization of aspergillus nidulans ornithine carbamoyltransferase in native host cells and in saccharomyces cerevisiae cells harbouring its cloned structural gene.differential centrifugation of the aspergillus nidulans cell lysate shows that ornithine carbamoyltransferase (ec 2.1.3.3) appears mainly in the particulate (organellar) fraction. the enzyme was located to the mitochondria by co-sedimentation with cytochrome oxidase in isopycnic density gradient and by cytochemical-electron microscopic means. arginase (ec 3.5.3.1) and ornithine delta-aminotransferase (e.c. 2.6.1.13) were found to reside in cytosol. the release of ornithine carbamoyltransferase f ...19863544621
5s rrna genes from aspergillus nidulans are not transcribed in saccharomyces cerevisiae.several different 5s rrna genes from aspergillus nidulans cloned in an escherichia coli--saccharomyces cerevisiae shuttle vector were introduced into s. cerevisiae cells by transformation. the a. nidulans 5s rrna genes were not transcribed in s. cerevisiae.19862436448
selectivity to k+ and na+ of protoplast fractions isolated from different regions of aspergillus nidulans hyphae.the selectivity to k+ and na+ of protoplast samples representing cytoplasm isolated from different regions of the hyphal filament of aspergillus nidulans was investigated. concentrations of both ions contained in successive protoplast fractions were measured. during lytic digestion, protoplasts were released first from apical regions and subsequently from progressively older regions of hyphae. a low k+/na+ ratio was found in protoplasts containing primarily apical cytoplasm and a high k+/na+ rat ...19863095487
an immunochemical study of neurospora nucleases.nucleases derived from neurospora crassa mycelia with neutral single-strand (ss) endodeoxyribonuclease activity have been examined by immunochemical techniques and by sodium dodecyl sulfate - dna gel electrophoresis. all of the intracellular nucleases, which have different divalent metal ion requirements, different strand specificities with single- and double-strand dna, different modes of action on dna and rna, and other distinguishing characteristics, are immunochemically related to neurospora ...19863013242
oxidative phosphorylation and energy buffering in cyanobacteria.the onset of respiration in the cyanobacteria anacystis nidulans and nostoc sp. strain mac upon a shift from dark anaerobic to aerobic conditions was accompanied by rapid energization of the adenylate pool (owing to the combined action of atp synthase and adenylate kinase) and also the guanylate, uridylate, and cytidylate pools (owing to nucleoside diphosphate and nucleoside monophosphate kinases). rates of the various transphosphorylation reactions were comparable to the rate of oxidative phosp ...19863023299
transformation of aspergillus nidulans with a cloned, oligomycin-resistant atp synthase subunit 9 gene.an allele (olic31) of the a. nidulans olic gene has been cloned using homology with the equivalent gene from n. crassa. olic31 codes for an oligomycin-resistant, triethyltin-hypersensitive form of subunit 9 of the mitochondrial atp synthase complex. direct selection for oligomycin-resistance was possible following transformation of a. nidulans with the olic31 gene. the phenotypes of transformants cultured in the presence of oligomycin were indicative of the position of integration of the transfo ...19863010049
gene cloning in aspergillus nidulans: isolation of the isocitrate lyase gene (acud).an aspergillus nidulans gene library was constructed in a high-frequency transformation vector, pdjb3, based on the neurospora crassa pyr4 gene. this gene library was used to isolate the structural gene for isocitrate lyase (acud) by complementation of a deficiency mutation following transformation of a. nidulans. plasmids rescued in escherichia coli were able to transform five different a. nidulans acud mutants. transformation using plasmids containing the cloned fragment resulted in integratio ...19863010050
genetics of filamentous fungi. 19862945991
amino acid transport in eucaryotic microorganisms. 19862947629
sequence and centromere proximal location of a transformation enhancing fragment ans1 from aspergillus nidulans.the aspergillus nidulans sequence ans1, previously known to enhance transformation frequencies of pyr4-based vectors, was shown to enhance the efficiency of argb and trpc-based vectors. increased efficiencies could be obtained by constructing vectors containing argb and ans1 or by cotransforming selectable plasmids (containing argb, trpc, or pyr4) with the non-selectable ans1 sequence. the preponderance of evidence suggests that the mechanism of ans1 activity does not involve homologous recombin ...19872825130
regulation of alcr, the positive regulatory gene of the ethanol utilization regulon of aspergillus nidulans.the alcr positive control gene is necessary for the expression of both alca (coding for alcohol dehydrogenase adh i), and alda (coding for aldehyde dehydrogenase, alddh) in aspergillus nidulans. using a cloned alcr probe and northern blots analysis we show that: (1) alcr itself is inducible; (2) alcr inducibility depends on the expression of the alcr gene itself; and (3) alcr is subject to carbon catabolite repression and its expression is controlled by the negatively acting crea wide specificit ...19872834622
multiple copies of the amds gene of aspergillus nidulans cause titration of trans-acting regulatory proteins.it has been established that a plasmid containing the amds gene of aspergillus nidulans may be used to transform amds+ strains by selecting for increased utilization of acetamide as sole nitrogen source. analysis of transformants has shown that multiple tandem copies of the plasmid can be integrated into the chromosome, commonly at sites other than the amds locus. while the transformed phenotype was relatively stable through mitotic and meiotic divisions evidence was found for variation in plasm ...19872835171
cloning of the ribob locus of aspergillus nidulans.we have complemented the ribob2 mutation of aspergillus nidulans by transformation with a plasmid library of wild-type (wt) sequences. we have isolated, by marker rescue from a ribob+ transformant, a plasmid that complements ribob2 efficiently. from this plasmid we have subcloned an a. nidulans sequence that complements ribob2 efficiently and that integrates by homologous recombination at a site closely linked to the ribob locus. we conclude that this sequence contains the wt ribob+ allele.19873038695
functional organization of the aspergillus nidulans trpc promoter.we investigated the functional organization of the aspergillus nidulans trpc promoter by the sequential removal of sequences upstream of the major trpc mrna cap site (+1). dna fragments containing promoter mutations were fused to the escherichia coli lacz gene, and a novel method was used to select for integration of the fusion gene at the aspergillus argb locus. beta-galactosidase assays and s1 nuclease protection experiments demonstrated that the promoter mutations affected gene expression in ...19873039345
the role of the n-terminus of the large subunit of ribulose-bisphosphate carboxylase investigated by construction and expression of chimaeric genes.the genes for the large and small subunits of ribulose bisphosphate carboxylase/oxygenase (rubisco) from anacystis nidulans have been expressed in escherichia coli under the control of the lac promoter to produce active enzyme. the enzyme can be purified from the cells to yield up to 200 mg rubisco/l cultured bacteria, and is indistinguishable from the enzyme extracted from a. nidulans. in order to investigate the role of the n-terminus of the large subunit in catalysis, chimaeric genes were con ...19873121325
evaluation of commercial serologic test reagents for immunoidentification of medically important aspergilli.we evaluated commercial serodiagnostic test reagents from greer laboratories (gl), lenoir, nc; immuno-mycologics, inc. (imi), norman, ok; and scott laboratories (sl), fiskville, ri; for their ability to detect aspergillus spp. exoantigens and group them in their proper series. we detected 87 culture extracts from coded cultures of aspergillus groups and heterologous fungi against anti-a. fumigatus, a. flavus, a. nidulans, a. niger, and a. terreus sera in the presence of their corresponding antig ...19873126020
a versatile transformation system for the cellulolytic filamentous fungus trichoderma reesei.an efficient transformation system for the cellulolytic filamentous fungus trichoderma reesei has been developed. transformation was obtained with plasmid carrying the dominant selectable marker amds or the argb gene of aspergillus nidulans, which was found to complement the respective argb mutation of t. reesei. the transformation frequency can be up to 600 transformants per microgram of transforming dna. the efficiency of co-transformation with unselected dna was high (approx. 80%). the transf ...19873127274
regulation of the mrna levels of nima, a gene required for the g2-m transition in aspergillus nidulans.the temperature-sensitive cell cycle mutation nima5 causes nuclei of aspergillus nidulans to be blocked in late g2 at restrictive temperature. under these conditions the spindle pole body divides but does not separate and the mitotic index drops to zero. if nima5 is blocked for more than one doubling time and then shifted from restrictive to permissive temperature, nuclei immediately enter mitosis, the mitotic spindle forms, and the chromosomes condense (oakley, b. r., and n. r. morris, 1983, j. ...19873294854
chemical and biological characterization of hazardous industrial waste. ii. eukaryotic bioassay of a wood-preserving bottom sediment.the eukaryotic haploid and diploid forms of aspergillus nidulans were used to detect gene mutations and various types of chromosome damage, respectively, in the acid, base and neutral fractions of a wood-preserving bottom sediment. the corresponding response to prokaryotic mutagenicity assays and major chemical constituents of the 3 waste fractions were described by donnelly et al. (1987). the haploid methionine system detected genotoxic compounds in all 3 primary waste fractions without metabol ...19873306353
demonstration of an altered phenylalanyl-trna synthetase in an analogue-resistant mutant of aspergillus nidulans.we have isolated and characterized a new class of p-fluorophenylalanine (fpa)-resistant mutant in aspergillus nidulans using a phena strain as the wild type, by optimizing the conditions of growth. all four spontaneous mutants selected on a medium containing fpa were found to be recessive to their wild-type alleles in heterozygous diploids. complementation analyses and linkage data showed that they were allelic and mapped at a single locus (fpau) in the faca-ribod interval on the right arm of li ...19873312953
suppressors suac109 and suaa101 of aspergillus nidulans alter the ribosomal phenotype in vitro.a new homologous, cell-free system for protein synthesis has been devised for use with ribosomes and elongation factors from aspergillus nidulans. ribosome preparations from strains with either the suaa101 or suac109 mutations have a higher misreading ratio (non-cognate:cognate amino acid incorporation) in the presence of hygromycin than controls. they can be classed as fidelity mutants. these results also prove that the mutations must be in genes coding for ribosomal proteins or enzymes which m ...19873331121
position-dependent and -independent mechanisms regulate cell-specific expression of the spoc1 gene cluster of aspergillus nidulans.many genes that are expressed specifically in the differentiating asexual spores (conidia) of aspergillus nidulans are organized into clusters. we investigated the effects of altered chromosomal position on expression of a gene from the conidiation-specific spoc1 gene cluster. the gene became deregulated when integrated at nonhomologous chromosomal sites, in that transcript levels were elevated in vegetative cells (hyphae) and variably altered in conidia. we also investigated the effects on expr ...19873550422
synthesis and biocidal activity of zn(ii) complexes of some 2,2'-substituted diphenylamines.binary as well as ternary complexes of zn(ii) with diphenylamine-2,2'-dicarboxylic acid (dpdc), diphenylamine-2-amino-2'-carboxylic acid (dpac), diphenylamine-2-hydroxy-2'-carboxylic acid (dphc), diphenylamine-2-mercapto-2'-carboxylic acid (dpmc), and n-(2-pyridino) anthranilic acid (npa) have been synthesized and characterized by their elemental analysis, ir spectral data, and molar conductance measurements. antimicrobial activity of these ligands and their respective zn(ii) complexes have been ...19873553430
fungal small nuclear ribonucleoproteins share properties with plant and vertebrate u-snrnps.snrnas with properties closely related to those of the major vertebrate u-snrnas are present in the fungi aspergillus nidulans, neurospora crassa and schizosaccharomyces pombe. these rnas possess a tri-methyl guanosine cap structure and a subset cross-hybridizes with human u1 and u2 clones. in the form of snrnps, snrnas from these fungi as well as from saccharomyces cerevisiae and pea plants are immunoprecipitated by human and anti-sm or anti-(u1)rnp autoimmune antibodies. on micro-injection int ...19872953599
complementation of area- regulatory gene mutations of aspergillus nidulans by the heterologous regulatory gene nit-2 of neurospora crassa.loss-of-function mutations in the regulatory gene area of aspergillus nidulans prevent the utilization of a wide variety of nitrogen sources. the phenotypes of nit-2 mutants of neurospora crassa suggest that this gene may be analogous to the area gene. transformation has been used to introduce a plasmid containing the nit-2 gene into a. nidulans. the nit-2 gene of neurospora complemented mutations in the area gene, restoring the ability to use a variety of nitrogen sources. this indicated that t ...19872954160
high level of complexity of small nuclear rnas in fungi and plants.the complexity of the trimethylguanosine-capped, small nuclear rna (snrna) populations in a number of organisms has been examined using immunoprecipitation and two-dimensional gels. from the fungi aspergillus nidulans and schizosaccharomyces pombe, over 30 major snrnas can be resolved. the most abundant of these correspond to the putative analogues of vertebrate u1, u2, u4 and u5, which have been reported to be precipitated by anti-sm antibodies, but other snrnas are little less abundant than th ...19872958638
the involvement of glutamine synthetase/glutamate synthase in ammonia assimilation by aspergillus nidulans.wild-type aspergillus nidulans grew equally well on nh4cl, kno3 or glutamine as the only nitrogen source. nadp+-dependent glutamate dehydrogenase (ec 1.4.1.4) and glutamine synthetase (gs; ec 6.3.1.2) activities varied with the type and concentration of nitrogen source supplied. glutamate synthase (gogat) activity (ec 1.4.7.1) was detected but it was almost unaffected by the type and concentration of nitrogen source supplied. ion exchange chromatography showed that the gogat activity was due to ...19872888838
the pentafunctional arom enzyme of saccharomyces cerevisiae is a mosaic of monofunctional domains.the nucleotide sequence of the saccharomyces cerevisiae aro1 gene which encodes the arom multifunctional enzyme has been determined. the protein sequence deduced for the pentafunctional arom polypeptide is 1588 amino acids in length and has a calculated mr of 174555. functional regions within the polypeptide chain have been identified by comparison with the sequences of the five monofunctional escherichia coli enzymes whose activities correspond with those of the arom multifunctional enzyme. the ...19872825635
identification and isolation of a putative permease gene in the quinic acid utilization (qut) gene cluster of aspergillus nidulans.mutations in the qutd gene of aspergillus nidulans cause the loss of ability to grow upon quinic acid as sole carbon source in media at normal ph 6.5 and failure to induce three enzyme activities specifically required for metabolism to protochatechuic acid. all 9 qutd mutants recovered are recessive and have been found to be ph sensitive, growing strongly on quinic acid media at ph 3.5 and producing significant induced enzyme activities. these properties are consistent with the hypothesis that t ...19872835177
saprophytic fungi isolated from animal and bird pens in egypt.forty-four samples collected from animal and bird pens were screened for their content of saprophytic fungi by using the dilution plate method. 76 species in addition to one variety of aspergillus flavus belonging to 33 genera were recovered on three types of media: 20 genera and 49 species on littman-oxgall agar, 19 genera and 41 species on cellulose- and 19 genera and 43 species on glucose-czapek's agar. the most frequent genera were aspergillus (21 species), scopulariopsis (4 species) and pen ...19873130473
comparison of the cis-acting control regions of two coordinately controlled genes involved in ethanol utilization in aspergillus nidulans.the alca and alda genes of aspergillus nidulans are regulated in exactly the same manner, being subject to positive control by the product of the alcr gene. we report the complete nucleotide sequence of the alca gene and its 5' non-coding region, preliminary localization of the region involved in the regulation of alca expression, and a detailed comparison of this region to the 5' non-coding region of alda (pickett et al., 1987). the 5' flanking regions of the genes contain six similar sequence ...19873297923
conditionally lethal tuba alpha-tubulin mutations in aspergillus nidulans.we have mapped 17 extragenic suppressors of bena33, a heat-sensitive beta-tubulin mutation of aspergillus nidulans, to the tuba alpha tubulin locus. fifteen of these tuba mutations cause cold sensitivity in a genetic background with bena33 and appear to cause lethality in a background with the wild-type bena allele. we examined the microtubule-mediated processes, nuclear division and nuclear migration, in seven different cold-sensitive double mutants, each carrying bena33 and a different cold-se ...19873302605
antisuppressor mutations in aspergillus nidulans: cold-resistant revertants of suppressor suac109. 19873305170
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