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helical packing in the hydrophobic sector of cytochrome c oxidase.an arrangement for the membrane-spanning segments of the three larger subunits of cytochrome c oxidase is proposed on the basis of sequence comparison and polarity distribution estimated from the data available for 11 different organisms.19852991455
direct and indirect gene replacements in aspergillus nidulans.we performed three sets of experiments to determine whether cloned dna fragments can be substituted for homologous regions of the aspergillus nidulans genome by dna-mediated transformation. a linear dna fragment containing a heteromorphic trpc+ allele was used to transform a trpc- strain to trpc+. blot analysis of dna from the transformants showed that the heteromorphic allele had replaced the trpc- allele in a minority of the strains. an a. nidulans trpc+ gene was inserted into the argb+ gene, ...19852991748
identification and molecular analysis of a third aspergillus nidulans alcohol dehydrogenase gene.an aspergillus nidulans functional cdna encoding an alcohol dehydrogenase (adh) was isolated by its ability to complement an adh1 mutation in saccharomyces cerevisiae. alignment of the cdna and cloned genomic dna sequences indicated that the adh gene contains two small introns. the presence of ethanol in the growth medium was shown to result in adh mrna accumulation presumably due to transcriptional induction of the gene. however, adh mrna accumulation was at most only partially repressed by the ...19852998782
nucleotide sequence of the phosphoenolpyruvate carboxylase gene of the cyanobacterium anacystis nidulans.nucleotide sequence of the open reading frame (orf) for the phosphoenolpyruvate carboxylase gene (ppc) of the cyanobacterium anacystis nidulans was determined. the orf consists of 3159 bp and codes for 1053 amino acid (aa) residues. the codon usage of the ppc of a. nidulans is not so markedly different from that of the escherichia coli ppc, yet, in a. nidulans the preferred codons are aag for lysine and ccc for proline, whereas those are seldom used in the e. coli ppc.19852998946
development of a high-frequency transforming vector for aspergillus nidulans.the pyr4 gene of neurospora crassa, which codes for orotidine-5'-phosphate decarboxylase, is capable of transforming an aspergillus nidulans pyrg mutant by chromosomal integration, despite low homology between the transforming dna and the recipient genome. integration of pfb6, a plasmid carrying pyr4 and capable of replication in escherichia coli, was not observed at the pyrg locus. the efficiency of transformation was considerably enhanced (50-100 fold) by inclusion in the transforming vector o ...19853000883
expression of an escherichia coli beta-galactosidase fusion gene in aspergillus nidulans.we inserted in frame the escherichia coli lacz gene into the protein-coding region of the aspergillus nidulans trpc gene and introduced the resultant fused gene into the a. nidulans genome. a functional beta gal fusion protein was produced. removal of the trpc transcription and translation initiation sequences from the fusion gene abolished production of the fusion protein, showing that expression is dependent on these sequences. thus, lacz fusions should be of use for estimating gene activity i ...19853005133
self-cloning in the cyanobacterium anacystis nidulans r2: fate of a cloned gene after reintroduction.functional analysis of cloned genes often makes use of complementation after introducing these genes into cells of a mutant strain. problems with this self-cloning step in the cyanobacterium anacystis nidulans r2 have been encountered, which were mainly due to recombinational instability of gene and vector after transformation. therefore, conditions determining the exchange of material between chromosome, insert and plasmids were studied to achieve the necessary stability. the fate of plasmid pm ...19853006100
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
purification and preliminary characterization of alcohol dehydrogenase from aspergillus nidulans.aspergillus alcohol dehydrogenase is produced in response to growth in the presence of a wide variety of inducers, of which the most effective are short-chain alcohols and ketones, e.g. butan-2-one and propan-2-ol. the enzyme can be readily extracted from fresh or freeze-dried cells and purified to homogeneity on blue sepharose in a single step by using specific elution with nad+ and pyrazole. the pure enzyme has mr 290 000 by electrophoresis or gel filtration; it is a homopolymer with subunit m ...19853156582
polyamines in microorganisms. 19853157043
genomic clones of aspergillus nidulans containing alca, the structural gene for alcohol dehydrogenase and alcr, a regulatory gene for ethanol metabolism.our aim was to obtain from aspergillus nidulans a genomic bank and then clone a region we expected from earlier genetic mapping to contain two closely linked genes, alca, the structural gene for alcohol dehydrogenase (adh) and alcr, a positive trans-acting regulatory gene for ethanol metabolism. the expression of alca is repressed by carbon catabolites. a genomic restriction fragment characteristic of the alca-alcr region was identified, cloned in pbr322, and used to select from a genomic bank i ...19853158502
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
primary structure of the trpc gene from aspergillus nidulans.we have determined the structure and complete nucleotide sequence of the trifunctional trpc gene from the ascomycetous fungus aspergillus nidulans. results from rna gel blot analyses showed that this gene encodes two size classes of polyribosomal, poly (a)+rnas with approximate lengths of 2,400 and 2,600 nucleotides. s1 nuclease protection studies demonstrated that the distribution into the two size classes is due to selection of alternative sites for polyadenylation. the transcription units con ...19853158796
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
genetics of filamentous fungi. 19862945991
amino acid transport in eucaryotic microorganisms. 19862947629
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
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
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
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
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
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
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
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
structural genes for phosphatases in aspergillus nidulans. 19863011590
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
exploiting classical genetics to clone a eukaryotic regulatory gene. 19863153577
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
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
the susceptibility of photosynthesis to photoinhibition and the capacity of recovery in high and low light grown cyanobacteria, anacystis nidulans.the susceptibility of photosynthesis to photoinhibition and the rate of its recovery were studied in the cyanobacterium anacystis nidulans grown at a low (10 micromoles per square meter per second) and a high (120 micromoles per square meter per second) photosynthetically active radiation. the rate of light limited photosynthetic o(2) evolution was measured to determine levels of photoinhibition and rates of recovery. studies of photoinhibition and recovery with and without the translation inhib ...198716665264
genetic transformation of the fungal pathogen responsible for rice blast disease.the analysis of complex genetic determinants that control the ability of a fungus to colonize its host has been impaired by the lack of sophisticated genetic tools for characterizing important pathogens. we have developed a system for the genetic transformation of magnaporthe grisea, the causal agent of rice blast disease, to overcome this limitation. a m. grisea arginine auxotroph was shown to contain a mutation (arg3-12) that abolishes ornithine carbamoyltransferase activity. m. grisea strains ...198716593854
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
mms sensitivity of all amino acid-requiring mutants in aspergillus and its suppression by mutations in a single gene.all available amino acid-requiring mutants of aspergillus nidulans were found to be hypersensitive to mms (methyl methanesulfonate) to various degrees. on mms media, secondary mutations could be selected which suppress this mms sensitivity but do not affect the requirement. many such mutations were analyzed and found to be alleles of one gene, smsa (= suppressor of mms sensitivity), which mapped distal on the right arm of chromosome v. this gene is more likely to be involved in general regulatio ...19873556318
biosynthesis of thiamin. different biosynthetic routes of the thiazole moiety of thiamin in aerobic organisms and anaerobic organisms.the nitrogen atom of glycine was incorporated into the thiazole moiety of thiamin in the aerobic microorganisms bacillus subtilis, pseudomonas putida, saccharomyces cerevisiae, mucor racemosus, neurospora crassa, and emericella nidulans. it was not incorporated in the case of the facultative anaerobic microorganisms escherichia coli and enterobacter aerogenes, which, however, did incorporate the nitrogen atom of tyrosine. these results show that aerobic microorganisms and facultative anaerobic m ...19873566774
use of alpha- and beta-tubulin mutants for the study of spontaneous and induced chromosomal mis-distribution in aspergillus nidulans.the effect of two different mutations, one involving an alpha-tubulin (tuba) and the other a beta-tubulin (bena33) gene, on somatic segregation has been investigated in diploid strains of a. nidulans. both mutations, particularly bena33, increase the level of spontaneous chromosomal mis-distribution (cmd) phenomena, without affecting the frequency of crossing-over. the employment of homozygous strains for each of the two mutations in sensitivity tests toward various chemicals, allowed the clear ...19873574324
the nature of l8 and l8s8 forms of ribulose bisphosphate carboxylase/oxygenase from chromatium vinosum.l8 and l8s8 forms of ribulose bisphosphate carboxylase/oxygenase (rubisco) have been prepared from chromatium vinosum by the extremely mild method of centrifugal fractionation. only the l8s8 form is detectable in crude extracts of this organism. both forms show immunological identify in double diffusion studies using antibody to l subunits of the l8s8 form. l subunits from both l8 and l8s8 enzymes are identical by the criteria of peptides observed after limited proteolysis and n-terminal sequenc ...19873579306
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
development of a homologous transformation system for aspergillus niger based on the pyrg gene.the development of a homologous transformation system for aspergillus niger is described. the system is based on the use of an orotidine-5'-phosphate decarboxylase deficient mutant (pyrg) and a vector, pab4-1, which contains the functional a. niger pyrg gene as a selection marker. transformation of the a. niger pyrg mutant with pab4-1 resulted in the appearance of stable pyr+ transformants at a frequency of 40 transformants per microgram of dna. in 90% of these transformants integration had occu ...19873472035
differential riboflavin deposition in white and variegated white mutants of drosophila hydei.riboflavin deposition in organs of drosophila hydei was studied by means of a growth test using a riboflavin-deficient strain of the fungus aspergillus nidulans. in wild-type animals, riboflavin is deposited in malpighian tubules (mt) and testes but not in adult eyes. certain white (w) mutants do not contain riboflavin, whereas intermediately colored w mutants contain minor amounts of the substance. riboflavin-containing mt cells contain special globules that can be fixed and stained with the re ...19873502968
induction and isolation of mutants in fungi at low mutagen doses.since the yield of mutants per surviving cell increases in general with increasing dose of mutagen, it has often been concluded in the literature that it is the most efficient to apply high mutagen doses so that most spores are killed. as high doses of mutagen produce chromosome rearrangements and unnoticed mutations which disturb the genetic background, the relationship between mutant frequency and survival was analyzed with aspergillus nidulans as a model. it is shown that for different types ...19873329055
microheterogeneity in aspergillus nidulans 5s rrna genes.we have determined the sequence of 4 aspergillus nidulans 5s rrna genes and compared it with 4 previously established sequences. no extensive homologies are found in 5' flanking sequences, but in the 3' flanks of two genes and two pseudogenes similar sequences are observed. in the coding sequences differences occur in 7 positions. two 5s rrna genes which are found in one plasmid 1.1 kb apart are located in opposite orientations.19873329974
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
cloning and molecular analysis of the ornithine carbamoyl transferase gene of aspergillus niger.we have cloned the gene encoding ornithine carbamoyl transferase (octase) from aspergillus niger. the structure and complete nucleotide sequence of this gene have been determined. the gene encodes an mrna of 1.3 kb. the transcription unit contains an open reading frame of 1110 nucleotides (nt) which shows strong homology to the octase of aspergillus nidulans along most of its length. the n terminus, which shows little or no homology to other octases, is highly basic and is probably involved in m ...19873443301
detection of point-mutation mutagens in aspergillus nidulans: comparison of methionine suppressors and arginine resistance induction by fungicides.in the present study we describe the effect of 4 fungicides on the induction of point mutations in strains bia1 methg1 (induction of methionine suppressors) and 118 (induction of arginine resistance) of aspergillus nidulans. captan, which was used as a known mutagen, daconil 2787 and dithane m-45 were effective in inducing these mutations, whereas the fungicide cercobin caused no significant increase in the induction frequency of the point mutations selected. actually, a decrease in the frequenc ...19873540650
chemical and physical agents assayed in tests for mitotic intergenic and intragenic recombination in aspergillus nidulans diploid strains.data from aspergillus nidulans mitotic recombination assays published over the period 1960-1986 are briefly reviewed. the results of the testing of 104 chemical agents and three physical agents are summarized. a tentative comparison of the performance of recombinational, mutational and aneuploidy assays in a. nidulans suggests that the former can effectively detect dna-damaging agents which either induce true genetic recombination (intergenic or intragenic crossing-over) or mimic it by inducing ...19873328037
cloning, mapping and molecular analysis of the pyrg (orotidine-5'-phosphate decarboxylase) gene of aspergillus nidulans.we have modified the transformation procedures of ballance et al. [biochem. biophys. res. commun. 112 (1983) 284-289] to give increased rates of transformation in aspergillus nidulans. with the modified procedures we have been able to complement pyrg89, a mutation in the orotidine-5'-phosphate decarboxylase gene of a. nidulans, by transformation with a library of wild-type (wt) sequences in pbr329. we have recovered, by marker rescue from one such transformant, a plasmid (pjr15) that carries an ...19873328733
fixing on an enigma. 19873153172
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
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
transformation of penicillium chrysogenum using the aspergillus nidulans amds gene as a dominant selective marker.the aspergillus nidulans acetamidase gene (amds) has been used to transform penicillium chrysogenum at low frequency. several transformants were tested and shown to be mitotically stable. southern blot analysis indicated that transforming dna had integrated into the chromosomal dna, possibly at multiple sites.19873131026
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
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
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