TitleAbstractYear(sorted ascending)
differential expression of ustilago maydis dna sequences during induction of nitrate reductase enzyme activity.a differential hybridisation screen of an ustilago maydis genomic dna library was used to identify dna sequences transcribed at higher levels under growth conditions which induce nitrate reductase activity. after two rounds of screening, four different sequences showed a strongly enhanced hybridisation signal with an induced cdna probe relative to a repressed cdna probe. the sequence in plasmid pmh3007 hybridised to a u. maydis rna transcript of a 4.2 kb. this is identical in size to a transcrip ...19883224386
a phosphate-repressible acid phosphatase gene from aspergillus niger: its cloning, sequencing and transcriptional analysis.the cloning and sequencing of an aspergillus niger gene encoding a secreted form of phosphate-repressible acid phosphatase by complementation of a paca (phosphate-repressible acid phosphatase) mutant of aspergillus nidulans is described. the gene contains two introns, 201 and 265 nt in length, and codes for a 1.6-kb transcript. both phosphate concentration and ph of the growth medium affect the level of expression of the gene in a. niger. similar regulation is observed in a. nidulans transforman ...19883224828
microorganisms associated with mouldiness of dried yam chips and their prevention.the broad objective of this study was to isolate and identify the microorganisms causing mouldiness of stored yam chips and to look for ways of preventing the problem. microorganisms isolated included aspergillus flavus, a. glaucus, a. nidulans, a. niger, a. ochraceous, a. tamarii, a. candidus, penicillium oxalicum, trichoderma longibrachyatum, rhizopus nigricans, cylindrocarpon radicicola, neurospora crassa, botryodiplodia theobromae, bacillus subtilis, bacillus cereus, erwinia carotovora and s ...19883231261
interpretation of uv-survival curves of aspergillus conidiospores.semi-logarithmic dose-response curves for survival of uv-irradiated conidiospores of a. nidulans have an initial shoulder (at low doses) followed by a decline which becomes linear. to explain the initial shoulder and the resulting extrapolation number (log s intercept of the linear extrapolation line) a general model is presented, which includes multi-target (n) and multi-hit (h) effects and allows for the effect of initial repair and of a compound parameter k, which stands for inherent sensitiv ...19883275884
spindle formation and chromatin condensation in cells blocked at interphase by mutation of a negative cell cycle control aspergillus nidulans the temperature-sensitive cell cycle mutation bime7 causes chromosome condensation and pre-anaphase spindle formation to occur at restrictive temperature. by constructing double mutants between bime7 and s phase or g2 phase mutants and blocking dna replication with hydroxyurea, we demonstrate that bime7 can cause chromatin condensation and spindle formation in cells held in s or g2. thus bime7 overrides normal control systems that prevent mitosis from prematurely occurrin ...19883277718
nuclear migration in a nud mutant of aspergillus nidulans is inhibited in the presence of a quantitatively normal population of cytoplasmic microtubules.nuclear migration was studied in germinating conidia of a temperature-sensitive mutant of the fungus aspergillus nidulans. at the restrictive temperature motility was demonstrably impaired because significantly fewer nuclei migrated into the germ tube relative to a population of similarly sized germlings grown at the permissive temperature. further comparison of these populations showed that the mutant was leaky in that an increasing number of nuclei migrated as the total nuclear content increas ...19883279053
on the mutagenic and recombinogenic activity of certain herbicides in salmonella typhimurium and in aspergillus nidulans.the plant growth-regulating hormones indole-3-acetic acid (iaa) and indole-3-butyric acid (iba), both strong recombinogens in aspergillus nidulans, were tested in salmonella typhimurium strains for his revertants at a range of concentrations from 1 to 2000 micrograms/plate with and without metabolic activation and were found negative. also 3 herbicides of the chlorophenoxy group, 2,4-(dichlorophenoxy)acetic acid (2,4-d), 2,4-(dichlorophenoxy)butyric acid (2,4-db) and 4-chloro-2-methylphenoxyacet ...19883280995
mutants of aspergillus nidulans with increased resistance to the alkylating agent, n-methyl-n'-nitro-n-nitrosoguanidine.the isolation and characterisation of mutants of aspergillus nidulans showing resistance to mnng is described. such isolates were stable through prolonged subculture in the absence of the selective agent, and resistance segregated as an allele of a single gene in meiotic and mitotic analysis. mnng-resistant strains showed an increase in resistance to ems and uv irradiation but no cross-resistance to mms was detected. possible mechanisms of resistance to alkylating agents are discussed.19883283539
an uvsb mutant of aspergillus nidulans with high variable spontaneous mutation and intergenic mitotic recombination uv-sensitive mutant has been isolated with a new technique which allows isolation of uv-sensitive and uv-non-mutable mutants in aspergillus nidulans. this mutant is an allele of the known uvsb gene but shows some features not previously described in the alleles so far isolated. its more important characteristics are: (1) frequency of mitotic intergenic recombination is strongly increased in uvs/uvs diploids and it is highly variable in different clones: it varies from a minimum of 40-fold to ...19883283545
a new gene controlling sulphite reductase in aspergillus nidulans. 19883284789
similarity of nucleotide sequences at splicing sites. 19883287170
brla is necessary and sufficient to direct conidiophore development in aspergillus nidulans.the brla gene of a. nidulans mediates the developmental switch from the indeterminate, apical growth pattern of vegetative cells to the budding growth pattern of conidiophores. brla encodes a 432 amino acid polypeptide containing two directly repeated motifs resembling the zn(ii) coordination sites first recognized in xenopus tfiiia. misscheduled expression of brla in vegetative cells results in transcriptional activation of developmentally regulated genes, cessation of unidirectional hyphal gro ...19883293800
developmental regulation of a conidiation specific beta-tubulin in aspergillus nidulans.a beta-tubulin gene previously suggested to participate in conidial development in the filamentous fungus aspergillus nidulans is shown to be developmentally regulated in its expression. a quantitative s1 assay was used to show that the abundance of the tubc messenger rna increases during conidial development relative to the bena messenger rna. morphological analysis of cultures, used to prepare rna for the s1 analysis, demonstrated that the increase in tubc messenger rna was directly correlated ...19883294063
cloning and nucleotide sequence of the aroa gene of bordetella pertussis.the aroa locus of bordetella pertussis, encoding 5-enolpyruvylshikimate 3-phosphate synthase, has been cloned into escherichia coli by using a cosmid vector. the gene is expressed in e. coli and complemented an e. coli aroa mutant. the nucleotide sequence of the b. pertussis aroa gene was determined and contains an open reading frame encoding 442 amino acids, with a calculated molecular weight for 5-enolpyruvylshikimate 3-phosphate synthase of 46,688. the amino acid sequence derived from the nuc ...19882897356
action spectra for nitrate and nitrite assimilation in blue-green algae.action spectra for the assimilation of nitrate and nitrite have been obtained for several blue-green algae (cyanobacteria) with different accessory pigment composition. the action spectra for both nitrate and nitrite utilization by nitrate-grown anacystis nidulans l-1402-1 cells exhibited a clear peak at about 620 nanometers, corresponding to photosystem ii (psii) c-phycocyanin absorption, the contribution of chlorophyll a (chl a) being barely detectable. the action spectrum for nitrate reductio ...198816666041
identification and purification of a derepressible alkaline phosphatase from anacystis nidulans r2.we have examined the increase in alkaline phosphatase activity in the cyanobacterium anacystis nidulans r2 upon phosphate deprivation. much of the activity is released into the medium when a. nidulans is osmotically shocked, indicating that the enzyme is located either in the periplasmic space or is loosely bound to the cell wall. the polypeptide associated with phosphatase activity has been identified as a single species of m(r) 160,000. several lines of evidence demonstrate that this polypepti ...198816666051
genetic transformation of an argb mutant of aspergillus argb mutant of aspergillus oryzae nrrl 492 has been genetically transformed with the aspergillus nidulans argb gene. protoplasts were generated with a combination of novozyme 234 and beta-glucuronidase and regenerated on sucrose-stabilized minimal medium without arginine as described for a. nidulans. a frequency of 5 to 10 transformants per mug of dna was obtained; however, most transformants appeared abortive. the a. nidulans argb gene and vector sequences appeared to be integrated into the ...198816347669
cloning, expression and directed mutagenesis of the genes for ribulose bisphosphate carboxylase/oxygenase.the dominant natural form of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) is composed of large (l) 55-kda and small (s) 15-kda subunits. this enzyme (as the l8s8 form) is widely distributed among oxygenic photosynthetic species and among chemosynthetic bacteria. another form lacking small subunits is found as an l2 dimer in rhodospirillum rubrum or an l oligomer of uncertain aggregation state from rhodopseudomonas spharoides. the present article reviews two basically different appro ...198824425168
binding, uptake and expression of foreign dna by cyanobacteria and isolated etioplasts.discoveries of the uptake and expression of various escherichia coli plasmids by the cyanobacterium anacystis nidulans and isolated cumber etioplasts are reviewed. in particular, the binding and uptake of nick-translated (32)p-labeled plasmids and the expression of genes in the native plasmids are considered.permeaplasts of a. nidulans 6301 and isolated edta-washed cucumber etioplasts exhibit binding and uptake of dna that is unaffected by uncouplers of photophosphorylation or by dissipators of ...198824425366
electrofusion of protoplasts from celery (apium graveolens l.) with protoplasts from the filamentous fungus aspergillus nidulans.a method was developed for electrofusion of higher-plant protoplasts from celery and protoplasts from the filamentous fungus aspergillus nidulans. initially, methods for the fusion of protoplasts from ecch species were determined individually and, subsequently, electrical parameters for fusion between the species were determined. pronase-e treatment and the presence of calcium ions markedly increased celery protoplast stability under the electrical conditions required and increased fusion freque ...198924212750
one enzyme makes a fungal pathogen, but not a saprophyte, virulent on a new host plant.certain genes of nectria haematococca, a fingal pathogen of pea (pisum sativum), encode pisatin demethylase (pda), a cytochrome p-450 monoxygenase that detoxifies the phytoalexin pisatin. because pda is required by n.haematococca for pathogenicity on pea, pisatin helps defend pea against n. haematococca. the possibility that pisatin is a general defense factormicrothat is, that pda can confer pathogenicity to fungi not normally pathogenic on peamicrowas investigated. genes encoding pda were tran ...198917839018
a large cluster of highly expressed genes is dispensable for growth and development in aspergillus nidulans.we investigated the functions of the highly expressed, sporulation-specific spoc1 genes of aspergillus nidulans by deleting the entire 38-kb spoc1 gene cluster. the resultant mutant strain did not differ from the wild type in (1) growth rate, (2) morphology of specialized reproductive structures formed during completion of the asexual or sexual life cycles, (3) sporulation efficiency, (4) spore viability or (5) spore resistance to environmental stress. thus, deletion of the spoc1 gene cluster, r ...19892471671
enhancement of aspergillus nidulans transformation by the ans1 sequence.we have shown that the aspergillus nidulans ans1 sequence enhances the efficiency of transformation when introduced into vectors containing argb or trpc genes. increased efficiency of transformation is also observed when ans1 is present on a second cotransforming plasmid. in an attempt to explains the ans1 transactivity we have performed analysis of some cotransformants.19892484740
relationship between a 47-kda cytoplasmic membrane polypeptide and nitrate transport in anacystis nidulans.the polypeptide composition of cytoplasmic membranes of the cyanobacterium anacystis nidulans changes in response to variations in the nitrogen source available to the cells, differing specifically in the amount of a polypeptide of 47-kda molecular mass. synthesis of the polypeptide and expression of nitrate transport activity are repressed by ammonium. transfer of ammonium-grown cells to a medium containing nitrate as the sole nitrogen source results in parallel development of the 47-kda polype ...19892492194
thioredoxin is essential for photosynthetic growth. the thioredoxin m gene of anacystis nidulans.we have taken advantage of the transformation properties of the cyanobacterium anacystis nidulans r2 to investigate the importance of thioredoxin for photosynthetic growth. the gene encoding thioredoxin m, designated trxm, was cloned from a. nidulans using a synthetic oligonucleotide probe. based on the nucleotide sequence, thioredoxin m of a. nidulans is composed of 107 amino acids and shares 84, 48, and 48% sequence identity with thioredoxins from anabaena, spinach, and escherichia coli, respe ...19892492995
dna sequence and secondary structures of the large subunit rrna coding regions and its two class i introns of mitochondrial dna from podospora anserina.dna sequence analysis has shown that the gene coding for the mitochondrial (mt) large subunit ribosomal rna (rrna) from podospora anserina is interrupted by two class i introns. the coding region for the large subunit rrna itself is 3715 bp and the two introns are 1544 (r1) and 2404 (r2) bp in length. secondary structure models for the large subunit rrna were constructed and compared with the equivalent structure from escherichia coli 23s rrna. the two structures were remarkably similar despite ...19892494353
genes for the ribosomal proteins s12 and s7 and elongation factors ef-g and ef-tu of the cyanobacterium, anacystis nidulans: structural homology between 16s rrna and s7 mrna.a 6.5 kb region from the genome of the cyanobacterium, anacystis nidulans 6301 was cloned using the tobacco chloroplast gene for ribosomal protein s12 as a probe. sequence analysis revealed the presence of genes for ribosomal proteins s12 and s7 and elongation factors ef-g and ef-tu in this dna region. the arrangement is rps12 (124 codons) - 167 bp spacer - rps7 (156 codons) - 77 bp spacer - fus (694 codons) - 26 bp spacer - tufa (409 codons), which is similar to that of the escherichia coli str ...19892499762
cloning, sequence analysis and transcriptional study of the isopenicillin n synthase of penicillium chrysogenum as-p-78.a gene (ips) encoding the isopenicillin n synthase of penicillium chrysogenum as-p-78 was cloned in a 3.9 kb sali fragment using a probe corresponding to the amino-terminal end of the enzyme. the sali fragment was trimmed down to a 1.3 kb ncoi-bglii fragment that contained an open reading frame of 996 nucleotides encoding a polypeptide of 331 amino acids with an mr of 38012 dalton. the predicted polypeptide encoded by the ips gene of strain as-p-78 contains a tyrosine at position 195, whereas th ...19892499766
cloning and characterization of an anacystis nidulans r2 superoxide dismutase gene.the e. coli iron superoxide dismutase gene (sodb) was utilized as a heterologous probe to isolate a superoxide dismutase (sod) gene from anacystis nidulans r2. nucleotide sequence analysis revealed a 603 bp open reading frame with deduced amino acid sequence similar to other sod genes and to cyanobacterial superoxide dismutase amino-terminal sequences. assuming proteolytic cleavage of the initial methionine residue, the molecular mass of the mature a. nidulans r2 sodb polypeptide is 22,000 dalto ...19892501651
development of an expression system in aspergillus nidulans. 19892502450
expression of the escherichia coli beta-glucuronidase gene in industrial and phytopathogenic filamentous fungi.a chimaeric beta-glucuronidase (gus) gene has been created by ligating the aspergillus nidulans glyceraldehyde 3-phosphate dehydrogenase promoter to the coding sequence of the e. coli uida gene. co-transformation of this vector into a. nidulans, a. niger and the tomato pathogen fulvia fulva (syn. cladosporium fulvum (cooke] resulted in the expression of beta-glucuronidase. gus activity was detected by growth on agar media containing x-gluc and by enzyme assays of mycelial extracts. expression of ...19892504501
cloning and molecular characterisation of the amdr controlled gata gene of aspergillus nidulans.the gamma-amino-n-butyrate transaminase gene (gata) of aspergillus nidulans is one of several genes under positive control by the regulatory gene amdr (also called inta). the gata gene has been cloned from a cosmid library by complementation of a gata mutation. the sequence of a 2.6 kb genomic fragment containing gata has been determined. an open reading frame of 1497 bp within this sequence is interrupted by three putative introns and predicts a protein of 55 kda. northern analysis confirms con ...19892505051
expression of the trpc gene from penicillium chrysogenum in aspergillus nidulans.the heterologous expression in aspergillus nidulans of a gene involved in tryptophan biosynthesis from penicillium chrysogenum is described. with the chimeric plasmid ppc-31, which carries the cloned trpc gene, approximately 10-40 "stable" transformants per microgram of dna were obtained, with selection for complementation of the mutant allele. this frequency was increased 10-fold by the insertion of the ans1 fragment into the transformation vector. southern hybridization analysis revealed that ...19892508698
duplication of the phycocyanin operon in the unicellular cyanobacterium anacystis nidulans r2.two phycocyanin (pc) operons, each containing alpha- and beta-subunit genes, have been isolated from the unicellular cyanobacterium anacystis nidulans r2. using oligodeoxyribonucleotide probes for the pc-coding regions, three psti fragments were obtained and shown to contain the two operons, which are 2.7 kb apart, with a proposed gene order of 5'-(beta i-alpha i)-(beta ii-alpha ii)-3'. the nucleotide sequences of both alpha-subunit genes are identical, as are the beta-sequences and the 51-bp in ...19892511077
aspergillus and mouse share a new class of 'zinc finger' protein. 19892511649
[properties of 2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5'- phosphate reductase, a enzyme of the second stage of flavinogenesis in pichia guilliermondii yeasts].2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5'-phosphate reductase has been isolated from cells of pichia guilliermondii and subjected to 20-fold purification by treating extracts with streptomycin sulphate, frationating proteins (nh4)2so4 at 45-75% of saturation and chromatography on blue sepharose cl-6b. the use of gel filtration through sephadex g-150 and chromatography on deae-cellulose proved to be less effective for the enzyme purification. it has been established that it is 2,5-diamino-4-o ...19892511652
high-performance liquid chromatographic determination of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine in complex media by precolumn derivatisation with dansylaziridine.a novel method is described for the trace level quantitation of the tripeptide delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) in complex fermentation media, using a high-performance liquid chromatographic, pre-column derivatisation technique. the procedure is based upon the reaction of the acv monomer with 5-dimethylaminonaphthalene-1-sulphonylaziridine (dansylaziridine) and produces a highly fluorescent product. reaction conditions between the reagent and tripeptide were investigated an ...19892512319
expression of an anacystis nidulans photolyase gene in escherichia coli; functional complementation and modified action spectrum of photoreactivation.the anacystis nidulans photolyase gene inserted in an expression vector plasmid was introduced into escherichia coli cells and the production of anacystis photolyase protein was confirmed by reaction with antibodies raised against photolyase purified from a. nidulans cells. the anacystis photolyase functioned in photoreactivation repair defective e. coli cells. the e. coli transformants exhibited an action spectrum with a maximum around 380 nm similar to that of e. coli photolyase in contrast wi ...19892516329
cobalt-induced inhibition of growth in cyanobacteria anabaena doliolum and anacystis nidulans: interaction with sulphur containing amino acids.cobalt, above 1 microm concentration was growth inhibitory for both a. doliolum and a. nidulans. its toxicity was mitigated by sulphur containing amino acids (cystine and cysteine), however, methionine could not mitigate the cobalt toxicity at all.19892517422
purification and characterisation of nad-glutamate dehydrogenase from aspergillus nidulans.nad-glutamate dehydrogenase has been purified from mycelia of a. nidulans. the enzyme comprises subunits of 110 kda. it is located in the cytosol. it is completely denatured by 1.0 m guanidine hydrochloride, and is not renatured by subsequent dilution. isophthalate is a strong competitive inhibitor and the enzyme is also inhibited by thiol reagents. the properties of the enzyme were compared to those from other fungi in terms of size, sensitivity to inhibitors, intracellular distribution and mod ...19892524418
genetic engineering of filamentous fungi.filamentous fungi are important in medicine, industry, agriculture, and basic biological research. for example, some fungal species are pathogenic to humans, whereas others produce beta-lactam antibiotics (penicillin and cephalosporin). industrial strains produce large amounts of enzymes, such as glucoamylase and proteases, and low molecular weight compounds, such as citric acid. the largest and most economically important group of plant pathogens are fungi. several fungal species have biologica ...19892525275
processing of mitochondrial rna in aspergillus nidulans.genes for cytochrome oxidase subunit i (oxia), atpase subunit 9, nadh dehydrogenase subunit 3 (ndhc) and cytochrome oxidase subunit ii (oxib) are located within a 7.2 kb (1 kb = 10(3) bases or base-pairs) segment of the aspergillus nidulans mitochondrial genome. northern hybridization shows that abundant rna molecules of 4.0, 2.5 and 1.5 kb, each containing copies of two or more genes, are transcribed from this region. the 4.0 kb molecule, which contains copies of each of the four genes but lack ...19892530353
production of cell wall-degrading enzymes by aspergillus nidulans: a model system for fungal pathogenesis of plants.the cell wall-degrading enzymes polygalacturonase and pectate lyase have been suggested to be crucial for penetration and colonization of plant tissues by some fungal pathogens. we have found that aspergillus nidulans (= emericella nidulans), a saprophytic ascomycete, produces levels of these enzymes equal to those produced by soft-rotting erwinia species. induction of polygacturonase and pectate lyase in a. nidulans requires substrate and is completely repressed by glucose. surprisingly, inocul ...19892535501
regulation of the aspergillus nidulans pectate lyase gene (pela).aspergillus nidulans pectate lyase was purified from culture filtrates. the enzyme catalyzed a random eliminative cleavage reaction, had an apparent molecular weight of 40,000, and a pl of 4.2. pectate lyase antisera were produced and used to identify pectate lyase clones in a cdna expression library. thirteen of 14 clones identified immunologically cross-hybridized. the identity of the single-copy pectate lyase gene, which we designated pela, was confirmed in two ways. first, several cdna clone ...19892535502
protein encoded by the third intron of cytochrome b gene in saccharomyces cerevisiae is an mrna maturase. analysis of mitochondrial mutants, rna transcripts proteins and evolutionary relationships.we have established the nucleotide sequence of the wild-type and that of a trans-acting mutant located in the third (bi3) intron of the saccharomyces cerevisiae mitochondrial cytochrome b gene. the intron, 1691 base-pairs long, has an open reading frame 1045 base-pairs long, in phase with the preceding exon and the mutation replaces the evolutionarily conserved gly codon of the second consensus motif by an asp codon and blocks the formation of mature cytochrome b mrna. splicing intermediates of ...19892538624
the bimg gene of aspergillus nidulans, required for completion of anaphase, encodes a homolog of mammalian phosphoprotein phosphatase aspergillus nidulans, the temperature-sensitive, recessive cell cycle mutation bimg11 causes an elevated mitotic index at restrictive temperature and an inability to complete the anaphase separation of daughter nuclei. we have shown that this mutation has an abnormally high content of nuclear phosphoproteins and that the wild-type gene encodes a type 1 protein phosphatase. we conclude that dephosphorylation of a key protein(s) is required to complete mitosis.19892544297
nucleotide sequence and regulation of expression of the aspergillus nidulans gdha gene encoding nadp dependent glutamate dehydrogenase.the nucleotide sequence of the aspergillus nidulans gdha gene encoding nadp linked glutamate dehydrogenase has been determined and northern blot analysis used to study the regulation of expression of this gene. the gdha gene is 1485 nucleotides long and, by comparison with the corresponding neurospora crassa am gene, has two putative introns of 53 nucleotides and a protein encoding region of 1380 nucleotides that codes for an inferred protein of 49.63 kda which shows regions of homology with glu ...19892550758
invasive aspergillus infection in chronic granulomatous disease: treatment with itraconazole. 19892555469
cloning of a new bidirectionally selectable marker for aspergillus strains.mutants that lack adenosine triphosphate sulfurylase (atpsase; ec are unable to use sulfate as sole source of sulfur and are also resistant to selenate. these mutants, denoted sc-, are readily obtained from any strain of aspergillus niger or aspergillus nidulans by the strong selection for selenate resistance. we have cloned the gene encoding atpsase from a. nidulans by complementation of an sc mutant strain of a. nidulans with a gene library and show that plasmids containing this gene ...19892558969
isolation of the faca (acetyl-coenzyme a synthetase) and acue (malate synthase) genes of aspergillus nidulans.acetate inducible genes of aspergillus nidulans were cloned via differential hybridization to cdna probes. using transformation of mutant strains the genes were identified as faca (acetyl-coenzyme a synthetase) and acue (malate synthase). the levels of rna encoded by these genes were shown to be acetate inducible and subject to carbon catabolite repression. induction is abolished in a facb mutant and carbon catabolite repression is relieved in a crea mutant.19892571070
ammonia assimilation by aspergillus nidulans: [15n]ammonia study.15n kinetic labelling studies were done on liquid cultures of wild-type aspergillus nidulans. the labelling pattern of major amino acids under 'steady state' conditions suggests that glutamate and glutamine-amide are the early products of ammonia assimilation in a. nidulans. in the presence of phosphinothricin, an inhibitor or glutamine synthetase, 15n labelling of glutamate, alanine and aspartate was maintained whereas the labelling of glutamine was low. this pattern of labelling is consistent ...19892574737
physical characterization of the aldehyde-dehydrogenase-encoding gene of aspergillus facilitate a better understanding of the regulation of alda, the gene encoding aldehyde dehydrogenase (alddh) in the ascomycete fungus, aspergillus niger, the gene has been physically characterized. the complete nucleotide (nt) sequence of the gene and its flanking regions has been determined. analysis of the gene has revealed the presence of three introns. the homologous gene in the related fungus, aspergillus nidulans, contains only two introns. the coding regions of these genes, excluding ...19892606357
tryptophan auxotrophic mutants in aspergillus niger: inactivation of the trpc gene by cotransformation mutagenesis.aspergillus niger tryptophan auxotrophic mutants have been isolated after uv irradiation of conidiospores. the mutants belong to two different complementation groups, trpa and trpb, which complement each other in heterokaryons. neither of the mutations could be complemented with the cloned a. niger trpc gene. to obtain a. niger trpc mutants in a direct way, gene inactivation by cotransformation was performed. for this purpose an in-frame gene fusion between the a. niger trpc and escherichia coli ...19892615762
amplified expression of ribulose bisphosphate carboxylase/oxygenase in pbr322-transformants of anacystis nidulans.prior research suggested that the genes for large (l) and small (s) subunits of ribulose bisphosphate carboxylase/oxygenase (rubisco) are amplified in ampicillin-resistant pbr322-transformants of anacystis nidulans 6301. we now report that chromosomal dna from either untransformed or transformed a. nidulans cells hybridizes with nick-translated [32p]-pbr322 at moderately high stringency. moreover, nick-translated [32-p]-pcs75, which is a puc9 derivative containing a psti insert with l and s subu ...19892644909
delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase from aspergillus nidulans. the first enzyme in penicillin biosynthesis is a multifunctional peptide synthetase.a multienzyme catalyzing the formation of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine, the first free intermediate in penicillin biosynthesis, was detected in an assay measuring the formation of tripeptide from l-[u-14c]valine in the presence of l-alpha-aminoadipic acid, l-cysteine, atp, mg2+ ions, and dithioerythritol. enzyme was extracted from dry mycelium using a buffer with a high glycerol concentration and thiol protective agent to stabilize enzyme activity. in five steps the enzyme wa ...19892645274
genotoxic effects of niclosamide in aspergillus nidulans.a 2-5-month treatment with niclosamide, a widely used drug in developing countries, has been reported to induce lymphosarcomas in toad liver and kidney. the genotoxic effects of this drug have also been evaluated in salmonella typhimurium, in somatic and germinal cells of mice and in human lymphocytes exposed in vitro and in vivo. the present study shows that niclosamide is also capable of inducing mitotic crossing-over and non-disjunction in aspergillus nidulans, which points to the wide potent ...19892649793
identification of gamma-tubulin, a new member of the tubulin superfamily encoded by mipa gene of aspergillus nidulans.microtubules, which are essential for mitosis and many other cytoskeletal functions, are composed primarily of alpha- and beta-tubulin. the properties of microtubules are due, in part, to proteins other than tubulins that are part of, or interact with, microtubules and the identification and characterization of such proteins is important to understanding how microtubules function. analyses of mutations at the mipa (microtubule interacting protein) locus of aspergillus nidulans have suggested tha ...19892649796
transformation in fungi.transformation with exogenous deoxyribonucleic acid (dna) now appears to be possible with all fungal species, or at least all that can be grown in culture. this field of research is at present dominated by saccharomyces cerevisiae and two filamentous members of the class ascomycetes, aspergillus nidulans and neurospora crassa, with substantial contributions also from fission yeast (schizosaccharomyces pombe) and another filamentous member of the class ascomycetes, podospora anserina. however, tr ...19892651864
a translocation associated, loss-of-function mutation in the nitrogen metabolite repression regulatory gene of aspergillus nidulans can revert intracistronically.the arear-18 mutation is a loss-of-function mutation in area, the positive acting regulatory gene mediating nitrogen metabolite repression in aspergillus nidulans. it results from a reciprocal translocation which splits the coding region into 5' and 3' moieties. surprisingly, we have selected rare intracistronic revertants of arear-18. from crosses heterozygous for arear-18 revertant alleles, duplication-deficiency progeny containing two copies of a substantial portion of chromosome iv but lacki ...19892651886
regulatory genes in aspergillus nidulans.a major area for the study of gene regulation in lower eukaryotes has been the coordinated control of catabolic enzyme synthesis. studies of catabolic gene regulation aim to define how interactions between input signals and regulatory proteins are transmitted to the transcription machinery to bring about changes in gene expression. in the past, mutants altered in the utilization of a wide variety of substrates have been characterized in aspergillus nidulans. recently, the development of a transf ...19892652389
interrelated regulation of sulphur-containing amino-acid biosynthetic enzymes and folate-metabolizing enzymes in aspergillus aspergillus nidulans homocysteine can be metabolized both to cysteine and methionine. mutants impaired in the main pathway of cysteine synthesis or in the sulphate assimilation pathway show a low pool of glutathione and elevated levels of homocysteine synthase and of the homocysteine-to-cysteine pathway enzymes. on the other hand, the level of methionine synthase and other enzymes of folate metabolism is depressed in these mutants. this anticoordinated regulation provides a mechanism controll ...19892653822
beta-lactam biosynthetic genes. 19892654524
different action of mms and ems in uv-sensitive strains of aspergillus nidulans.the repair of methyl methanesulfonate (mms) and ethyl methanesulfonate (ems) damages has been investigated in the fungus aspergillus nidulans. 4 uv-sensitive mutants, namely uvsb, uvsd, uvsf and uvsh have been tested for their sensitivity and mutability to the above-mentioned agents. the results obtained show that: (1) uvsb and uvsd mutants are no more sensitive than the wild-type strain to the lethal action of ems. in contrast, they are more sensitive to mms; (2) uvsf and uvsh mutants are more ...19892654626
interactions of three sequentially expressed genes control temporal and spatial specificity in aspergillus development.aspergillus nidulans brla, abaa, and weta form a dependent pathway that regulates asexual reproductive development. the order in which these genes are expressed determines the outcome of development. expression of brla in vegetative cells leads to activation of abaa and weta, cessation of vegetative growth, cellular vacuolization, and spore formation. by contrast, expression of abaa in vegetative cells does not result in conidial differentiation but does lead to activation of brla and weta, cess ...19892655931
the mitochondrial ribosomal rna molecules of aspergillus nidulans.the 16s and 23s mitochondrial rrnas of aspergillus nidulans have been identified by northern hybridisation and the ends of the molecules mapped onto the mitochondrial genome by s1 nuclease analysis. the results show that both the rrna molecules are longer than originally reported, forcing a reassessment of the potential secondary structures that can form in the terminal regions. in particular, structures resembling the 5.8s- and 4.5s-like domains of the bacterial large rrna can now be recognised ...19892656406
molecular characterization of the aspergillus nidulans ya locus.we investigated the molecular organization of the region of aspergillus nidulans chromosome i containing ya, a gene encoding the developmentally regulated enzyme conidial laccase. dna fragments were identified that complemented the ya2 mutation and were shown to correspond to ya by genetic mapping and gene disruption experiments. the molecular map of the region was oriented to the genetic map by testing dna fragments for their ability to complement a mutation in the tightly linked ade gene. the ...19892659435
isolation of a sexual sporulation hormone from aspergillus nidulans.psi factor is a substance produced by aspergillus nidulans that induces premature sexual sporulation. chromatographic analysis of psi-active extracts showed that psi activity resides in several different forms. two of the forms, psia1 and psib1, have been isolated and have been shown to have closely similar compositions. the most abundant form, psia1, reacts with alcohols in acidic solution by the addition of one entire molecule of the alcohol. this reaction, which is reversible, suggests that p ...19892661541
sterigmatocystin production on complex and defined substrates. 19892662007
nucleotide sequence of the aspergillus nidulans mitochondrial gene for subunit 5 of nadh dehydrogenase. 19892662141
the genetic analysis of mitosis in aspergillus nidulans.we describe here recent work on the molecular genetics of mitosis in the filamentous fungus aspergillus nidulans. aspergillus is one of three simple eukaryotes with powerful genetic systems that have been used to analyze mitosis. the modern molecular biological techniques available with this organism have made it possible to use mutations to identify genes and proteins that play an important role in mitosis. three aspergillus genes that affect mitosis are described. one gene, nima, is specifical ...19892662965
chromosomal mapping and gene disruption of the adhiii gene in aspergillus nidulans.there are at least three alcohol dehydrogenases in aspergillus nidulans. adhiii has no obvious physiological function. we describe here the cloning of the adhiii gene (alcc), its mapping on linkage group vii by "reverse genetics", and the properties of multicopy transformants tested for their ability to grow on a range of alcohols (butan-1-ol being the best substrate tested for growth). we were unable to detect any obvious alteration in phenotype of a strain carrying a disrupted copy of the adhi ...19892663191
developmentally related changes in the production and expression of endo-beta-1,4-glucanases in aspergillus nidulans.the production and electrophoretic expression of endoglucanase(s) were compared in the wild-type and three developmental mutants of aspergillus nidulans. in the wild type, the production of endoglucanase and its distribution in extracellular and intracellular fractions varied with the age of the culture and the yield was better in stable cultures (production of conidia and cleistothecia) as compared with shake cultures (vegetative hyphae only). two developmental mutants, aco-t69 and aco-40, whic ...19892663642
the proline transport protein of aspergillus nidulans is very similar to amino acid transporters of saccharomyces aspergillus nidulans, the gene prnb encoding the major proline transport system is one of a cluster of four genes necessary and sufficient for the utilization of proline as sole nitrogen and/or carbon source. the prn cluster has been cloned and the sequence and transcript map of the prnb gene are presented in this paper. the predicted translated sequence consists of 570 amino acids, resulting in a molecular weight of 63,028 daltons. its hydropathy profile shows 10 hydrophobic segments typical ...19892664423
cloning and physical characterization of the l-proline catabolism gene cluster of aspergillus nidulans.the proline catabolism gene cluster of aspergillus nidulans was cloned using a 'brute force' technique which detects clones hybridizing to restriction fragments overlapping chromosomal rearrangements. a number of deletion mutations and a translocation mutation in the cluster have been physically mapped, and an excellent correlation between the genetic and physical maps was established. transcripts have been identified and orientated for each of the four genes of the cluster. all are monocistroni ...19892668692
nucleotide sequence of the only unidentified reading frame in the aspergillus nidulans mitochondrial genome. 19892668894
electrophoretic karyotype of aspergillus electrophoretic karyotype of aspergillus nidulans has been obtained using contour-clamped homogeneous electric field gel electrophoresis. six chromosomal bands were separated, with two of the bands migrating as doublets. using the schizosaccharomyces pombe and saccharomyces cerevisiae chromosomes as size standards, we estimate the sizes of the chromosomes to be between 2.9 and 5.0 megabase pairs (mb) with a total genome size of approximately 31 mb. four of the eight genetic linkage groups wer ...19892668960
isolation and characterization of the 3-phosphoglycerate kinase gene (pgk) from the filamentous fungus trichoderma reesei.the 3-phosphoglycerate kinase gene (pgk) from trichoderma reesei was isolated by hybridization with the corresponding saccharomyces cerevisiae pgk gene. the 1,545 nt long nucleotide sequence of the cloned gene codes for a 416 amino acid protein. the coding sequence contains two introns of 219 and 75 nt, respectively, at positions identical to those corresponding genes from the other filamentous fungi aspergillus nidulans and penicillum chrysogenum. this gene codes for two mrnas of about 1.65 kb ...19892670282
characterization of the amdr-controlled lama and lamb genes of aspergillus nidulans.four aspergillus nidulans genes are known to be under the control of the trans-acting regulatory gene amdr. we describe the isolation and initial characterization of one of these amdr-regulated genes, lama. the lam locus, however, was found to consist of two divergently transcribed genes, the lama gene, and a new gene, also under amdr control, which we have designated lamb. using recombinant dna techniques we have constructed a strain of a. nidulans lacking a functional lamb gene. experiments co ...19892670667
a gene coding for the uric acid-xanthine permease of aspergillus nidulans: inactivational cloning, characterization, and sequence of a cis-acting aspergillus nidulans, integration of transforming sequences can proceed through recombination with homologous sequences or at heterologous sites in the genome. in a strain with a large deletion in the gene coding for acetamidase (amds), a plasmid carrying this gene integrates into and inactivates uapa, the putative structural gene for uric acid-xanthine permease, with a frequency of 0.3%. the integration event occurs 3' to the open reading frame of amds. a 10-nucleotide sequence which occurs ...19892670668
cloning of the nitrate reductase gene (niad) of aspergillus nidulans and its use for transformation of fusarium heterologous transformation system for the phytopathogenic fungus fusarium oxysporum has been developed based on the use of the aspergillus nidulans nitrate reductase gene (niad). f. oxysporum nia- mutants were easily selected by chlorate resistance. the a. nidulans niad gene was isolated from a gene library by complementation of an a. nidulans niad mutant. the cloned gene is capable of transforming f. oxysporum nia- mutants at a frequency of up to ten transformants per microgram of dna. sout ...19892670677
gene function identified by interspecific transformation.aspergillus nidulans is able to utilize 2-pyrrolidinone as a nitrogen source while two related aspergillus species, a. niger and a. terreus, cannot. mutations in the lama gene of a. nidulans prevent growth on 2-pyrrolidinone. a plasmid (plam7) has been isolated containing the a. nidulans lama gene and a divergently transcribed adjacent gene of unknown function. transformation of a. terreus with subclones of plam7 showed that both genes are essential for the utilization of a new nitrogen source, ...19892670678
a single, phosphate-repressible deoxyribonuclease, dnase a, secreted in aspergillus nidulans.high levels of nuclease activities were identified in filtrates of aspergillus cultures after growth in low-but not in high-phosphate media. deoxyribonuclease activities, characterized extensively by column chromatography, showed a coincident single peak for ss- and ds-dnase which was distinct from the peak for rnase. both ss-dnase and ds-dnase are endonucleolytic and showed the highest activity in the presence of ca2+ and mn2+ (at ph 8.0). they also showed identical heat sensitivities suggestin ...19892673210
transformation of seven species of filamentous fungi using the nitrate reductase gene of aspergillus nidulans.a gene transfer system originally developed for fusarium oxysporum has been applied to seven species of filamentous fungi of agricultural and industrial importance. this transformation system relies on the selection of mutants deficient in nitrate reductase by positive screening. such mutants were recovered easily in all the fungi tested--without mutagenic treatments--through their resistance to chlorate. they were transformed by a plasmid vector (pan301) carrying the aspergillus nidulans wild-t ...19892673557
cloning of the crea gene from aspergillus nidulans: a gene involved in carbon catabolite repression.the crea gene from a. nidulans has been cloned by complementation of a non-revertable mutant allele using a genomic library and marker rescue techniques. the rescued sequence was subcloned and a 2.3 kb fragment identified which complements several crea mutant alleles. northern analyses showed that crea encodes a transcript of approximately 1.8 kb in length and that the levels of this transcript varied by up to two fold depending on the carbon source. transformants containing more than two extra ...19892673558
characterization of an inducible expression system in aspergillus nidulans using alca and tubulin-coding genes.plasmids have been constructed in which expression of a gene can be placed under the control of the inducible promoter of the alca gene encoding alcohol dehydrogenase i in aspergillus nidulans. simplified shuttle vectors carrying pyr4 which complements pyrg89 mutations have also been constructed. these are based on puc19 and retain alpha-peptide expression. the beta-tubulin genes, tubc and bena, have been placed under the control of alca and their expression studied. levels of expression can be ...19892673931
disparate evolution of yeasts and filamentous fungi indicated by phylogenetic analysis of glyceraldehyde-3-phosphate dehydrogenase genes.genes encoding glyceraldehyde-3-phosphate dehydrogenase (ec from several evolutionarily disparate organisms were used to construct a phylogenetic tree by evolutionary parsimony. the gapdh tree indicates that, in contrast to the presently accepted taxonomy of fungi, the yeasts saccharomyces cerevisiae and zygosaccharomyces rouxii evolved separately from the filamentous ascomycetes (such as aspergillus nidulans) with which these yeasts are classified. according to this tree, the saccharo ...19892674943
endochitinase from aspergillus nidulans implicated in the autolysis of its cell endochitinase from centrifuged autolyzed cultures of aspergillus nidulans has been purified 100 times. the enzyme has mw 27,000, pi of 4.8 units, ph optimum around 5 ph units. it is unstable at temperature greater than 70 degrees c and does not have a cation requirement. it is inhibited by hg2+, cu2+, ca2+ and ag+ and it does not have muramidase activity. the enzyme depolymerizes chitin rapidly with production of high molecular weight polysaccharides, and then slowly degrades these with produ ...19892676705
the highly divergent beta-tubulins of aspergillus nidulans are functionally internal 1.4-kb bst eii fragment was used to disrupt the bena gene and establish heterokaryons. the heterokaryons demonstrated that the molecular disruption of bena results in a recessive bena null mutation. conidia from a heterokaryon swell and germinate but cannot undergo nuclear division and are thus inviable. a chimeric beta-tubulin gene was constructed with the bena promoter driving the tubc structural gene. this chimeric gene construction was placed on a plasmid containing a selectable ...19892681229
isolation and analysis of the acetate regulatory gene, facb, from aspergillus nidulans.the facb gene of aspergillus nidulans is thought to be involved in acetate induction of enzymes required for acetate utilization and of the acetamidase encoded by the multiply regulated amds gene. in addition, some evidence suggests that the facb gene has a structural as well as a regulatory role in acetate metabolism. the facb gene was cloned from a cosmid library by complementation of the facb101 loss-of-function mutation. transformants receiving multiple copies of facb displayed stronger grow ...19892685573
aspergillus findings in aids patients suffering from cryptococcosis.because of the known pathogenicity of cryptococcus neoformans and of aspergilli depending on defined but different immunodeficiencies of the host, the evaluation of their simultaneous cultural detection in specimens of the respiratory tract of aids patients is of epidemiological, diagnostic, pathogenetic and therapeutic interest. in 10 out of 15 aids patients the following species of the genus aspergillus could be isolated either once or repeatedly during the course of cr. neoformans infections ...19892685598
a gene transfer system based on the homologous pyrg gene and efficient expression of bacterial genes in aspergillus oryzae.a homologous transformation system for aspergillus oryzae is described. the system is based on an a. oryzae strain deficient in orotidine-5'-phosphate decarboxylase (pyrg) and the vector pao4-2, which contains a functional a. oryzae pyrg gene as selection marker. transformation of the a. oryzae pyrg mutant with circular pao4-2 resulted in the appearance of pyr+ transformants at a frequency of up to 20 per micrograms of dna, whereas with linear pao4-2 up to 200 transformants per micrograms dna we ...19892688930
a comparative study on ethanol and acetaldehyde as inducers of chromosome malsegregation in aspergillus nidulans.the activity of ethyl alcohol and acetaldehyde on mitotic chromosome segregation and conidial germination in aspergillus nidulans was studied. ethanol effectively induced malsegregation in a narrow range of concentrations (4.5-5.5%, v/v) and was inactive at doses which arrested conidial germination (above 6%). the same bell-shaped dose-response curve was shown by the spindle poison chloral hydrate, which was active in the range 6-10 mm. acetaldehyde displayed a diphasic dose-response curve. gene ...19892689879
cloning and characterization of the trpc gene from an aflatoxigenic strain of aspergillus parasiticus.the trpc gene in the tryptophan biosynthetic pathway was isolated from an aflatoxigenic aspergillus parasiticus by complementation of an escherichia coli trpc mutant lacking phosphoribosylanthranilate isomerase (prai) activity. the cloned gene complemented an e. coli trpc mutant deficient in indoleglycerolphosphate synthase (igps) activity as well as an aspergillus nidulans mutant strain that was defective in all three enzymatic activities of the trpc gene (glutamine amidotransferase, igps, and ...19892690735
rhizoxin resistant mutants with an altered beta-tubulin gene in aspergillus nidulans.rhizoxin and ansamitocin p-3 (a maytansinoid compound), potent inhibitors of mammalian brain tubulin assembly, inhibit growth of a variety of fungi including aspergillus nidulans. mutants of a. nidulans, bena10 which is a benomyl resistant beta-tubulin gene mutant and tuba1 which is a benomyl supersensitive alpha-tubulin gene mutant, were both sensitive to rhizoxin and ansamitocin p-3 to the same extent as wild-type strains. we isolated 18 rhizoxin resistant mutants of a. nidulans. all of these ...19892691873
rna-mediated genetic transformation in aspergillus nidulans.we developed a model-system for correcting genetic alterations of an aspergillus nidulans strain (ribo, paba, bio, w, acr) by treating protoplasts with total rna extracted from another a. nidulans strain bearing wild type alleles for the same genetic markers. the results revealed the occurrence of a true genetic transformation. the phenomenon was rna-dependent since it was abolished by pancreatic ribonuclease treatment. the term retrotransformation is proposed since the rna messages artificially ...19892692827
beta-n-acetylglucosaminidase from aspergillus nidulans which degrades chitin oligomers during autolysis.a hexosaminidase from autolyzed cultures of aspergillus nidulans was purified 196 fold and characterized as a beta-n-acetylglucosaminidase (ec the enzyme has a mw of 190000, a pi of 4.3, and optimum ph of 5.0 and is unstable at temperatures above 50 degrees c. the enzyme is a glycoprotein with 19.5% sugars, mannose being the principal component. it binds strongly to chitin. the enzyme hydrolyzes different substrates. the ki with the competitive inhibitor 2-acetamido-2-deoxy-d-gluconol ...19892693201
genetic transformation of the filamentous yeast, trichosporon cutaneum, using dominant selection efficient transformation system for the filamentous yeast, trichosporon cutaneum, has been developed. transformation was obtained with plasmids carrying either the escherichia coli hygromycin b phosphotransferase-encoding gene (hph) or the streptoalloteichus hindustanus phleomycin-resistance gene (ble), as dominant selection markers. expression of both resistance-conferring genes was controlled by the gpd promoter and the trpc terminator, from aspergillus nidulans. the transformation frequenc ...19892693213
characterization of purine hydroxylase i from aspergillus nidulans.purine hydroxylase i from aspergillus nidulans was purified 850-fold. the purified preparations exhibited the spectral and catalytic properties, including broad specificity for oxidizing and reducing substrates, typical of molybdenum/flavin/iron-sulphur-containing hydroxylases (oxotransferases).19892693595
immunochemical assay applied to mycotoxin biosynthesis: elisa comparison of sterigmatocystin production by aspergillus versicolor and aspergillus nidulans.conventional thin layer and instrumental methods for analyzing mycotoxins and their precursors are time-consuming and make the investigation of mycotoxin biosynthesis particularly difficult. as an alternative, sensitive enzyme-liked immunosorbent assays (elisas) can be utilized to analyze for these compounds. in this report, sterigmatocystin production in test tube cultures of aspergillus versicolor atcc 18643 and aspergillus nidulans atcc 32610 were compared using competitive elisa. polyclonal ...19892693965
on the mechanisms of induced aneuploidy in aspergillus nidulans and validation of tests for genomic mutations. 19892696976
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