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the plasmid replicator ama1 in aspergillus nidulans is an inverted duplication of a low-copy-number dispersed genomic repeat.the ama1 sequence was isolated from a genomic library of aspergillus nidulans on the basis of its ability to enhance transformation frequency and generate phenotypically unstable transformants in this fungus. these properties were previously shown to be the result of extrachromosomal replication of ama1-bearing plasmids. here we demonstrate that ama1 is an inverted duplication of a sequence which has other isolated genomic copies. these sequences (mobile aspergillus transformation enhancers, or ...19968830247
aspergillus fabm encodes an essential product that is related to poly(a)-binding proteins and activates development when overexpressed.overexpression of several different aspergillus nidulans developmental regulatory genes has been shown to cause inappropriate developmental activation and growth inhibition. we previously exploited this observation that induced development caused growth inhibition in designing a screen to identify other genes that could activate development when overexpressed. we identified 16 mutants in which induced expression of different random genomic dna sequences caused growth inhibition, accumulation of ...19968978035
analysis of cre1 binding sites in the trichoderma reesei cbh1 upstream region.a 1.5-kb xbai-sacii fragment containing the upstream region of the trichoderma reesei cellobiohydrolase i gene (cbh1) has been sequenced. the 1.5-kb fragment contains eight 6-bp sites having an identical or similar sequence to the consensus sequence for binding a catabolite repressor, aspergillus nidulans crea. results of binding assays with the maltose-binding protein::cre1(10-131) fusion protein (cre1 is a catabolite repressor of t. reesei) and the cbh1 upstream region revealed that a 504-bp x ...19968978090
isolation of laccase gene-specific sequences from white rot and brown rot fungi by pcr.degenerate primers corresponding to the consensus sequences of the copper-binding regions in the n-terminal domains of known basidiomycete laccases were used to isolate laccase gene-specific sequences from strains representing nine genera of wood rot fungi. all except three gave the expected pcr product of about 200 bp. computer searches of the databases identified the sequence of each of the pcr products analyzed as a laccase gene sequence, suggesting the specificity of the primers. pcr product ...19968837429
sequence-specific binding sites in the taka-amylase a g2 promoter for the crea repressor mediating carbon catabolite repression.the n-terminal part of the crea protein encompassing two zinc fingers was expressed in escherichia coli as a fusion protein with the maltose binding protein (male) of e. coli. our results show that crea binds to the promoter of the taa-g2 gene encoding taka-amylase a of aspergillus oryzae. dnase i footprinting experiments showed that crea bound to three sites with high affinity and to one site with low affinity within the first 401-bp region upstream of the transcription initiation site. all of ...19968987852
cloning, molecular analysis and insertional mutagenesis of the bidirectional hydrogenase genes from the cyanobacterium anacystis nidulans.among cyanobacteria, the heterocystous, n2-fixing anabaena variabilis and the unicellular anacystis nidulans have recently been shown to possess an nad+-dependent, bidirectional hydrogenase. a 5.0 kb dna segment of the a. nidulans genome is now identified to harbor the structural genes hoxuyh coding for three subunits of the bidirectional hydrogenase. the gene arrangement in a. nidulans and in a. variabilis is remarkably dissimilar. in a. nidulans, but not in a. variabilis, the four accessory ge ...19968843154
sorption of cadmium by filamentous soil fungi.the article presents the evaluation of the short-term sorption of cd by selected soil fungi. the freundlich adsorption isotherm method for metal sorption modelling was applied. fungal strains belonging to two classes, zygomycetes and ascomycetes, were used. altogether, six species from ascomycetes (a. niger, a. nidulans, ps. boydii, t. koningii, p. janthinellum, p. verrucosum) and three from zygomycetes (r. rhizopodiformis, r. oryzae, r. pusillus) were examined. these fungi were selected for exp ...19968997697
cytokinesis in aspergillus nidulans is controlled by cell size, nuclear positioning and mitosis.the mycelium of aspergillus nidulans is composed of multinucleate cellular compartments delimited by crosswalls called septa. septum formation is dependent on mitosis and requires the recruitment of actin to the site of septum formation. employing a collection of temperature sensitive nuclear distribution (nuda2, nudc3 and nudf7), nuclear division (nima5, hfab3), and septation (sepd5, sepg1) mutants, we have investigated the interdependency among nuclear positioning, mitosis, and cell growth in ...19968856514
analysis of mutations in the crea gene involved in carbon catabolite repression in aspergillus nidulans.the molecular nature of a number of crea mutant alleles has been determined. three alleles analysed are missense mutations in the dna binding domain and predicted to reduce but not abolish binding. of the other four alleles, two result from frameshifts: one has a nonsense mutilation and the other has an inversion. all four alleles result in truncations of the protein after the zinc finger domain, such that the protein no longer contains at least the carboxy terminal 145 amino acids, so identifyi ...19968864218
nuva, an aspergillus nidulans gene involved in dna repair and recombination, is a homologue of saccharomyces cerevisiae rad18 and neurospora crassa uvs-2.a 40 kb genomic clone and 2.3 kb ecori subclone that rescued the dna repair and recombination defects of the aspergillus nidulans nuva11 mutant were isolated and the subclone sequenced. the subclone hybridized to a cosmid in a chromosome-specific library confirming the assignment of nuva to linkage group iv and indicating its closeness to bimd. amplification by pcr clarified the relative positions of nuva and bimd. a region identified within the subclone, encoding a c3hc4 zinc finger motif, was ...19968868425
gene expression from replicating plasmids in aspergillus nidulans.plasmids bearing the ama1 replicator from aspergillus nidulans are capable of extrachromosomal replication in this fungus as well as in other species. synthetic plasmids bearing the moderately expressed argb gene and the highly expressed, inducible beta-galactosidase gene (bgas) were introduced into fungal cells. expression of both genes was monitored by northern hybridization. it was demonstrated that transcription of bgas is induced and repressed normally, irrespective of whether the gene is i ...19969003309
conformational changes and the role of metals in the mechanism of type ii dehydroquinase from aspergillus nidulans.we have investigated the involvement of metal ions and conformational changes in the elimination reaction catalysed by type ii dehydroquinase from aspergillus nidulans. mechanistic comparisons between dehydroquinases and aldolases raised the possibility that, by analogy with type ii aldolases, type ii dehydroquinases may require bivalent metal ions for activity. this hypothesis was tested by a combination of metal analysis, effects of metal chelators and denaturation/renaturation experiments, al ...19968870678
a study of protein-water exchange through the off-resonance roesy experiment: application to the dna-binding domain of alcr.in this communication a new nmr experiment for the safe observation and quantification of water-protein exchange phenomena is presented. it combines a water-selective pulse, offering chemical shift-based separation, and the off-resonance roesy dynamic filter, which permits the elimination of the unwanted intramolecular dipolar cross relaxation of protein protons. moreover, pulsed field gradients are used for the suppression of radiation damping and the solvent signal. the straightforward incorpo ...19969008364
a temperature-sensitive splicing mutation in the bimg gene of aspergillus produces an n-terminal fragment which interferes with type 1 protein phosphatase function.progression through anaphase requires high levels of type 1 protein phosphatase (pp1) activity in a variety of eukaryotes, including aspergillus nidulans. a conditional lethal, temperature-sensitive mutant in one of the aspergillus pp1 genes, bimg, prevents the normal completion of anaphase when cells are grown at restrictive temperature and this has been shown to be due to a reduction in type 1 phosphatase activity. we show that the bimg11 allele is recessive to the wild-type allele in heterozy ...19968887549
isolation of two apsa suppressor strains in aspergillus nidulans.aspergillus nidulans reproduces asexually with single nucleated conidia. in apsa (anucleate primary sterigmata) strains, nuclear positioning is affected and conidiation is greatly reduced. to get further insights into the cellular functions of apsa, aconidial apsa strains were mutagenized and conidiating suppressor strains were isolated. the suppressors fell into two complementation groups, sama and samb (suppressor of anucleate metulae), sama mapped on linkage group 1 close to pyrg. the mutant ...19968889518
rna-mediated transformation in aspergillus nidulans recovers gene functions lost by deletion or by point mutations.this work presents the results on two different approaches of rna-mediated transformation in a. nidulans: a) the receptor strain was an argb2 (iii) mutant deficient in arginine (otcase deficient), and b) the receptor was an a. nidulans mutant defective in nitrate reductase synthesis due to a deletion in the niad gene (viii). the analyses of the arg+ and the nia+ retrotransformants allowed an insight on the fate and inheritance of the newly acquired characteristics. the occurrence and the study o ...19968891357
identification of bime as a subunit of the anaphase-promoting complex.the initiation of anaphase and exit from mitosis require the activation of a proteolytic system that ubiquitinates and degrades cyclin b. the regulated component of this system is a large ubiquitin ligase complex, termed the anaphase-promoting complex (apc) or cyclosome. purified xenopus laevis apc was found to be composed of eight major subunits, at least four of which became phosphorylated in mitosis. in addition to cdc27, cdc16, and cdc23, apc contained a homolog of aspergillus nidulans bime, ...19968895470
identification of subunits of the anaphase-promoting complex of saccharomyces cerevisiae.entry into anaphase and proteolysis of b-type cyclins depend on a complex containing the tetratricopeptide repeat proteins cdc16p, cdc23p, and cdc27p. this particle, called the anaphase-promoting complex (apc) or cyclosome, functions as a cell cycle-regulated ubiquitin-protein ligase. two additional subunits of the budding yeast apc were identified: the largest subunit, encoded by the apc1 gene, is conserved between fungi and vertebrates and shows similarity to bimep from aspergillus nidulans. a ...19968895471
the aspergillus flba rgs domain protein antagonizes g protein signaling to block proliferation and allow development.flba encodes an aspergillus nidulans rgs (regulator of g protein signaling) domain protein that is required for control of mycelial proliferation and activation of asexual sporulation. we identified a dominant mutation in a second gene, fada, that resulted in a very similar phenotype to flba loss-of-function mutants. analysis of fada showed that it encodes the alpha-subunit of a heterotrimeric g protein, and the dominant phenotype resulted from conversion of glycine 42 to arginine (fada(g42r)). ...19968895563
separation and partial purification of beta-glucosidase and two endoglucanases in aspergillus niveus.the thermotolerant aspergillus niveus strain rmf 7883 was grown in czapek medium, with filter paper cellulose. the proportion of mycelial-bound to extracellular enzymes was studied. most of the beta-glucosidase (80.9%) and endoglucanases (78.3%) activities were extracellular. the extracellular endoglucanases and beta-glucosidase were separated and partially purified by sephadex g-100 gel filtration, followed by ion exchange chromatography on cm-trisacryl m. two extracellular endoglucanases, eg i ...19969019140
parods--a study of parallel algorithms for ordering dna sequences.a suite of parallel algorithms for ordering dna sequences (termed parods) is presented. the algorithms in parods are based on an earlier serial algorithm, ods, which is a physical mapping algorithm based on simulated annealing. parallel algorithms for simulated annealing based on markov chain decomposition are proposed and applied to the problem of physical mapping. perturbation methods and problem-specific annealing heuristics are proposed and described. implementations of parallel single instr ...19968902353
three binding sites for the aspergillus nidulans pacc zinc-finger transcription factor are necessary and sufficient for regulation by ambient ph of the isopenicillin n synthase gene promoter.the isopenicillin n synthase (ipna) gene, encoding a key penicillin biosynthetic enzyme in aspergillus nidulans, represents a prototype of an alkaline-expressed gene. ipna is under ambient ph regulation, and its promoter (ipnap) contains binding sites for the zinc-finger transcription factor pacc. we show here that three of these sites, denoted ipna2, ipna3, and ipna4ab, are efficiently recognized by the protein in an isolated sequence context. single, double, and triple inactivation of these si ...19968910527
isolation of a gene involved in 1,3-beta-glucan synthesis in aspergillus nidulans and purification of the corresponding protein.saccharomyces cerevisiae has two highly homologous genes, fks1 and fks2, which encode interchangeable putative catalytic subunits of 1,3-beta-glucan synthase (gs), an enzyme that synthesizes an essential polymer of the fungal cell wall. to determine if gs in aspergillus species is similar, an fks homolog, fksa, was cloned from aspergillus nidulans by cross-hybridization, and the corresponding protein was purified. sequence analysis revealed a 5,716-nucleotide coding region interrupted by two 56- ...19968755864
the cyanobacterial thioredoxin gene is required for both photoautotrophic and heterotrophic growth.the gene encoding thioredoxin in the facultative heterotrophic cyanobacterium synechocytis sp. pcc 6803 (trxa) has been cloned by heterologous hybridization using the corresponding gene trxm from the cyanobacterium anacystis nidulans as a probe. the deduced amino acid sequence of trxa predicts a protein of relative molecular weight of 11,750 and has strong identity with its cyanobacterial counterparts and other m-type thioredoxins of photo-synthetic eukaryotes. the trxa gene has been expressed e ...19968756494
an extragenic suppressor of the mitosis-defective bimd6 mutation of aspergillus nidulans codes for a chromosome scaffold protein.we previously identified a gene, bimd, that functions in chromosome segregation and contains sequences suggesting that it may be a dna-binding protein. two conditionally lethal mutations in bimd arrest with aberrant mitotic spindles at restrictive temperature. these spindles have one-third the normal number of microtubules, and the chromosomes never attach to the remaining microtubules. for this reason, we hypothesized that bimd functioned in chromosome segregation, possibly as a component of th ...19968849887
nut1, a major nitrogen regulatory gene in magnaporthe grisea, is dispensable for pathogenicity.nut1, a gene homologous to the major nitrogen regulatory genes nit-2 of neurospora crassa and area of aspergillus nidulans, was isolated from the rice blast fungus, magnaporthe grisea. nut1 encodes a protein of 956 amino acid residues and, like nit-2 and area, has a single putative zinc finger dna-binding domain. functional equivalence of nut1 to area was demonstrated by introducing the nut1 gene by dna-mediated transformation into an area loss-of-function mutant of a. nidulans. the introduced n ...19968757395
the cu,zn superoxide dismutases of aspergillus flavus, aspergillus niger, aspergillus nidulans, and aspergillus terreus: purification and biochemical comparison with the aspergillus fumigatus cu,zn superoxide dismutase.cu,zn superoxide dismutases (sods) have been purified to homogeneity from aspergillus flavus and a. niger, which are significant causative agents of aspergillosis, and from a. nidulans and a. terreus, which are much rarer causative agents of disease, using a combination of isoelectric focusing and gel filtration fast protein liquid chromatography. the purified enzymes have been compared with the previously described sod from the most important pathogen in the genus, a. fumigatus (m. d. holdom, r ...19968757871
cell cycle regulation in aspergillus by two protein kinases.great progress has recently been made in our understanding of the regulation of the eukaryotic cell cycle, and the central role of cyclin-dependent kinases is now clear. in aspergillus nidulans it has been established that a second class of cell-cycle-regulated protein kinases, typified by nima (encoded by the nima gene), is also required for cell cycle progression into mitosis. indeed, both p34cdc2/cyclin b and nima have to be correctly activated before mitosis can be initiated in this species, ...19968760343
the 2.8 a structure of a t = 4 animal virus and its implications for membrane translocation of rna.simple rna animal viruses generally enter cells through receptor-mediated endocytosis followed by acid ph dependent release and translocation of rna across the endosomal membrane. the t = 3 nodaviruses contain prefabricated pentameric helical bundles that are cleaved from the remainder of the subunits by an assembly-dependent auto-proteolysis and they are positioned for release through 5-fold axes of the particle. we previously proposed that these bundles may serve as conduits for rna membrane t ...19968760498
a study of the structural basis of the ability of chlorinated alkanes and alkenes to induce aneuploidy and toxicity in the mold aspergillus nidulans.a knowledge-based system (multicase) was applied to the elucidation of the structural basis of the induction of aneuploidy and growth inhibition by a group of chlorinated alkanes and alkenes in aspergillus nidulans. it was found that while there were commonalities in the structural determinants associated with fungicidal and fungostatic activities, there were none between these and the structures associated with the induction of aneuploidy. moreover, there did not appear to be a commonality betw ...19968764947
[effect of zinc oxide on aspergillus species: a possible cause of local noninvasive aspergillosis of the maxillary sinus].during the last years the appearance of radiopaque concrements in the maxillary sinus was reported. these could be identified as root-filling material for teeth of the upper jaw containing zinc oxide. this suggested that excess root-filling material containing zinc oxide in the maxillary sinus could favour the development of a local, non-invasive aspergillosis. therefore, we tested aspergillus fumigatus, a. flavus, a. terreus, a. nidulans and a. niveus for the influence of zinc oxide. cza-pek-do ...19968767264
on the consistency of a physical mapping method to reconstruct a chromosome in vitro.during recent years considerable effort has been invested in creating physical maps for a variety of organisms as part of the human genome project and in creating various methods for physical mapping. the statistical consistency of a physical mapping method to reconstruct a chromosome, however, has not been investigated. in this paper, we first establish that a model of physical mapping by binary fingerprinting of dna fragments is identifiable using the key assumption-for a large randomly genera ...19968770604
screening of medicinal plants for induction of somatic segregation activity in aspergillus nidulans.knowledge about mutagenic properties of plants commonly used in traditional medicine is limited. a screening for genotoxic activity was carried out in aqueous or alcoholic extracts prepared from 13 medicinal plants widely used as folk medicine in cuba: lepidium virginicum l. (brassicaceae): plantago major l. and plantago lanceolata l. (plantaginaceae); ortosiphon aristatus blume, mentha x piperita l., melissa officinalis l. and plectranthus amboinicus (lour.) spreng. (lamiaceae); cymbopogon citr ...19968771452
isolation and characterization of the nuclease o gene (nuco) from aspergillus oryzae.nuclease o in the mycelia of aspergillus oryzae has been purified 55-fold by successive steps of chromatography from the filtrate of the autolyzate. the molecular mass of nuclease o was 32 kda, as estimated by sds polyacrylamide-gel electrophoresis. the nuclease o gene (nuco) encoding this enzyme was cloned and sequenced. the open reading frame is interrupted by four introns with conserved splice sites and contains 328 amino-acid residues of the mature enzyme. a. nidulans transformants obtained ...19968781174
molecular cloning and expression in saccharomyces cerevisiae of two aspergillus nidulans xylanase genes.two aspergillus nidulans genes, xlna and xlnb, encoding the x22 and x24 xylanases from this fungus, respectively, have been cloned and sequenced. their cdnas have been expressed in a laboratory saccharomyces cerevisiae strain under the control of a constitutive yeast promoter, resulting in the construction of recombinant xylanolytic yeast strains.19968787417
ca(2+)/calmodulin-dependent kinase is essential for both growth and nuclear division in aspergillus nidulans.the calmodulin gene has been shown to be essential for cell cycle progression in a number of eukaryotic organisms. in vertebrates and aspergillus nidulans the calmodulin dependence also requires calcium. we demonstrate that the unique gene encoding a multifunctional calcium/calmodulin-dependent protein kinase (camk) is also essential in a. nidulans. this enzyme is required both for the nuclear division cycle and for hyphal growth, because spores containing the disrupted gene arrest with a single ...19968898358
aspergillus nidulans stcp encodes an o-methyltransferase that is required for sterigmatocystin biosynthesis.the aspergillus nidulans stcp gene was previously identified as a transcribed region associated with a cluster of genes proposed to be involved in sterigmatocystin biosynthesis (d. w. brown, j.-h. yu, h. s. kelkar, m. fernandes, t. c. nesbitt, n. p. keller, t. h. adams, and t. j. leonard, proc. natl. acad. sci. usa 93:1418-1422, 1996). stcp was predicted to encode a methyltransferase responsible for conversion of demethylsterig-matocystin to sterigmatocystin. here we demonstrate that disruption ...19968900026
mitochondrial inheritance in aspergillus nidulans.mitochondrial chloramphenicol and oligomycin resistance mutations were used to investigate mitochondrial inheritance in a. nidulans. mitochondrial rflps could not be used to distinguish between paternal and maternal mitochondria because none were detected in the 54 isolates investigated. several thousand ascospores from each of 111 hybrid cleistothecia from 21 different crosses between 7 heterokaryon incompatible isolates were tested for biparental inheritance. all mitochondrial inheritance was ...19968801189
isolation and characterization of a calmodulin-encoding cdna from the pathogenic fungus histoplasma capsulatum.we describe in this paper the isolation and complete sequence of a calmodulin (cam) encoding cdna from the dimorphic pathogenic fungus histoplasma capsulatum (genbank accession u12505). the deduced amino acid sequence was identical to the cam of aspergillus nidulans and had only one amino acid difference from the cam of neurospora crassa. saccharomyces cerevisiae cam, however, has only about 60% amino acid identity compared with h. capsulatum. these data further support the close relationship of ...19968803795
asm-1+, a neurospora crassa gene related to transcriptional regulators of fungal development.this report describes the identification, cloning, and molecular analysis of asm-1+ (ascospore maturation 1), the neurospora crassa homologue of the aspergillus nidulans stua (stunted a) gene. the asm-1+ gene is constitutively transcribed and encodes an abundant, nucleus-localized 68.5-kd protein. the protein product of asm-1+ (asm-1), contains a potential dna-binding motif present in related proteins from a. nidulans (stua), candida albicans (efgtf-1), and saccharomyces cerevisiae (phd1 and sok ...19968913744
[regulation of folate metabolism in fungi: aspergillus nidulans as an experimental model]. 19968805185
the orla gene from aspergillus nidulans encodes a trehalose-6-phosphate phosphatase necessary for normal growth and chitin synthesis at elevated temperatures.a cosmid carrying the orla gene from aspergillus nidulans was identified by complementation of an orla1 mutant strain with dna from the pkby2 cosmid library. an orla1 complementing fragment from the cosmid was sequenced. orla encodes a predicted polypeptide of 227 amino acids (26360 da) that is homologous to a 211-amino-acid domain from the polypeptide encoded by the saccharomyces cerevisiae tps2 gene and to almost the entire escherichia coli otsb-encoded polypeptide. tps2 and otsb each specify ...19968809779
the isolation of a dol-p-man synthase from ustilago maydis that functions in saccharomyces cerevisiae.genomic dnas from several fungi were screened for a homologous sequence to saccharomyces cerevisiae dpm1, an essential gene which encodes dolichyl phosphoryl mannose synthase. the fungi examined included aspergillus nidulans, neurospora crassa, schizophyllum commune and ustilago maydis. only u. maydis gave a significant signal after southern hybridization using dpm1 as a probe. the ustilago homolog was subsequently cloned and sequenced. the predicted protein of 294 amino acids has 60% identity t ...19968813763
aspergillus endocarditis in chronic granulomatous disease.we report the first case, to our knowledge, of aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. a diagnosis was made on culture of the organism from the mass despite extensive prior investigation. the presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. we conclude that f ...19968816221
fast dissociation of phe-trna synthetase from aspergillus nidulans immobilized on sepharose-6b column by nacl.phenylalanyl-trna2) synthetase from aspergillus nidulans was efficiently immobilised to sepharose 6b column containing phenylalanine as the ligand. nacl was found to be a potent dissociating agent for the immobilised enzyme. while 0.5 m nacl in discontinuous elution showed a slow impetus on dissociation giving a plateaux profile, a solution of 0.8 m nacl made the elution rapid giving a sharp peak. on the other hand, in a gradient (continuous) elution the rapidity of dissociation was found to be ...19968819846
the cloning and sequencing of the alcb gene, coding for alcohol dehydrogenase ii, in aspergillus nidulans.alcohol dehydrogenase ii (adh ii, structural gene alcb) was purified from a strain h1035, bia1; alce1; alc500 alcd1, which produces 100-times more adh ii activity than the alcaalcr deletion strain (alc500). antibodies were raised against this adh, and were used to screen a cdna library in lambda gt11. we have isolated the gene for an adh which is over-expressed in h1035, and which we believe to be the alcb gene: cdna and genomic clones were sequenced. the sequence contains three introns and enco ...19968821658
isolation of differentially expressed cdna clones from salt-adapted aspergillus nidulans.differentially expressed cdna clones were isolated from salt-adapted aspergillus nidulans (fgsc #359). poly (a)+ rna from adapted mycelia was used to construct a lambda uni-zap cdna library. the library was screened with mixed subtracted cdna probes. three-hundred and fifty-seven positive plaques were isolated in the primary screening. sixty-two randomly selected plaques were purified and placed into eight different cross-hybridization groups. a representative cdna from each group was used to st ...19968821659
two s-phase checkpoint systems, one involving the function of both bime and tyr15 phosphorylation of p34cdc2, inhibit nima and prevent premature mitosis.we demonstrate that there are at least two s-phase checkpoint mechanisms controlling mitosis in aspergillus. the first responds to the rate of dna replication and inhibits mitosis via tyrosine phosphorylation of p34cdc2. cells unable to tyrosine phosphorylate p34cdc2 are therefore viable but are unable to tolerate low levels of hydroxyurea and prematurely enter lethal mitosis when s-phase is slowed. however, if the nima mitosis-promoting kinase is inactivated then non-tyrosine-phosphorylated p34 ...19968670863
characterisation of the aspergillus nidulans fra1 mutant: hexose phosphorylation and apparent lack of involvement of hexokinase in glucose repression.hexose phosphorylation was studied in aspergillus nidulans wild-type and in a fructose non-utilising mutant (fra). the data indicate the presence of at least one hexokinase and one glucokinase in wild-type a. nidulans, while the fra1 mutant lacks hexokinase activity. the a. nidulans gene encoding hexokinase was isolated by complementation of the fra1 mutation. the absence of hexokinase activity in the fra1 mutant did not interfere with glucose repression of the enzymes involved in alcohol and l- ...19968674991
identification of a major cis-acting dna element controlling the bidirectionally transcribed penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) of aspergillus nidulans.the beta-lactam antibiotic penicillin is produced as a secondary metabolite by some filamentous fungi. in this study, the molecular regulation of the aspergillus (emericella) nidulans penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) was analyzed. acva and ipna are divergently oriented and separated by an intergenic region of 872 bp. translational fusions of acva and ipna with the two escherichia coli reporter genes lacz and uida enabled us to measure the regulation of both genes simult ...19968682797
molecular characterisation of meab, a novel gene affecting nitrogen metabolite repression in aspergillus nidulans.mutations within the meab gene elicit the inappropriate expression of several activities subject to nitrogen metabolite repression in aspergillus nidulans and also have some unrelated phenotypic effects. we have cloned meab and isolated a full length cdna clone. northern analysis has shown that meab expression is not subject to nitrogen metabolite repression. meab encodes a novel protein of 418 amino acids and contains a significantly high number of s/tpxx motifs, a motif common in transcription ...19968690087
the detection and evaluation of aneugenic chemicals.although aneuploidy makes a significant contribution to both somatic and inherited disease the mechanisms by which environmental chemicals may induce numerical chromosome aberrations are only poorly defined. the european union project was aimed to further our understanding of those chemical interactions with the components of the mitotic and meiotic cell division cycle which may lead to aneuploidy and to characterise the parameters such as cellular metabolism which may influence the activity of ...19968692188
the genes yni1 and ynr1, encoding nitrite reductase and nitrate reductase respectively in the yeast hansenula polymorpha, are clustered and co-ordinately regulated.the nitrite reductase-encoding gene (yni1) from the yeast hansenula polymorpha was isolated from a lambda embl3 h. polymorpha genomic dna library, using as a probe a 481 bp dna fragment from the gene of aspergillus nidulans encoding nitrite reductase (niia). an open reading frame of 3132 bp, encoding a putative protein of 1044 amino acids with high similarity with nitrite reductases from fungi, was located by dna sequencing in the phages lambdanb5 and lambdaja13. genes yni1 and ynr1 (encoding ni ...19968694791
a novel family of developmentally regulated mammalian transcription factors containing the tea/atts dna binding domain.we describe the molecular cloning of two novel human and murine transcription factors containing the tea/atts dna binding domain and related to transcriptional enhancer factor-1 (tef-1). these factors bind to the consensus tea/atts cognate binding site exemplified by the gt-iic and sph enhansons of the sv40 enhancer but differ in their ability to bind cooperatively to tandemly repeated sites. the human tefs are differentially expressed in cultured cell lines and the mouse (m)tefs are differentia ...19968702974
the quta activator and qutr repressor proteins of aspergillus nidulans interact to regulate transcription of the quinate utilization pathway genese.genetic evidence suggests that the activity of the native quta transcription activator protein is negated by the action of the qutr transcription repressor protein. when aspergillus nidulans was transformed with plasmids containing the wild-type quta gene, transformants that constitutively expressed the quinate pathway enzymes were isolated. the constitutive phenotype of these transformants was associated with an increased copy number of the transforming quta gene and elevated quta mrna levels. ...19968704987
the ribosome-inactivating protein restrictocin deters insect feeding on aspergillus restrictus.the fungus-feeding beetle, carpophilus freemani, consumed equal quantities of young mycelia, fewer phialides bearing mature spores and much fewer phialides bearing developing spores of aspergillus restrictus compared to those of aspergillus nidulans when tested in diet choice assays. the degree to which specific fungal structures were consumed was inversely related to the localization of high levels of restrictocin, a ribosome-inactivating protein, to those structures. pure restrictocin added to ...19968704996
the aspergillus nidulans penicillin-biosynthesis gene aat (pende) is controlled by a ccaat-containing dna element.analysis of the promoter of the penicillin biosynthesis aat (pende) gene of aspergillus nidulans using band-shift assays led to the identification of a ccaat-containing dna element which was specifically bound by a protein (complex). the identified dna element was localised about 250 bp upstream of the transcriptional-start sites of aat. substitution of the ccaat core sequence by gatcc led to a fourfold reduction of expression of an aat-lacz gene fusion. the identified binding site thus was func ...19968706667
the hapc gene of aspergillus nidulans is involved in the expression of ccaat-containing promoters.the 5' regulatory region of the amds gene of aspergillus nidulans, which encodes an acetamidase required for growth on acetamide as a carbon and nitrogen source, contains a ccaat sequence which is required for setting the basal level of amds expression. mobility shift studies have identified a factor in a. nidulans nuclear extracts which binds to this ccaat sequence. in saccharomyces cerevisiae the hap3 gene encodes one component of a multisubunit complex that binds ccaat sequences. a search of ...19968709944
the aspergillus nidulans genes chsa and chsd encode chitin synthases which have redundant functions in conidia formation.we previously isolated three chitin synthase genes (chsa, chsb, and chsc) from aspergillus nidulans. in the present work, we describe the isolation and characterization of another chitin synthase gene, named chsd, from a. nidulans. its deduced amino acid sequence shows 56.7% and 55.9% amino acid identity, respectively, with cal1 of saccharomyces cerevisiae and chs3 of candida albicans. disruption of chsd caused no defect in cell growth or morphology during the asexual cycle and caused no decreas ...19968709948
the glucose repressor gene cre1 of trichoderma: isolation and expression of a full-length and a truncated mutant form.the cre1 genes of the filamentous fungi trichoderma reesei and t. harzianum were isolated and characterized. the deduced crei proteins are 46% identical to the product of the glucose repressor gene crea of aspergillus nidulans, encoding a dna-binding protein with zinc fingers of the c2h2 type. the cre1 promoters contain several sequence elements that are identical to the previously identified binding sites for a. nidulans crea. steady-state mrna levels for cre1 of the t. reesei strain qm9414 var ...19968709949
the chsd and chse genes of aspergillus nidulans and their roles in chitin synthesis.two chitin synthase genes, chsd and chse, were identified from the filamentous ascomycete aspergillus nidulans. in a region that is conserved among chitin synthases, the deduced amino acid sequences of chsd and chse have greater sequence identity to the polypeptides encoded by the saccharomyces cerevisiae chs3 gene (also named csd2, cal1, dit101, and kti1) and the candida albicans chse gene than to other chitin synthases. chse is more closely related to the chs3 genes, and this group constitutes ...19968810520
regulation of acid phosphatases in an aspergillus niger pacc disruption strain.an aspergillus niger strain has been constructed in which the ph-dependent regulatory gene, pacc, was disrupted. the pacc gene of a. niger, like that of a. nidulans, is involved in the regulation of acid phosphatase expression. disruptants were identified by a reduction in acid phosphatase staining of colonies. southern analysis demonstrated integration of the disruption plasmid at the pacc locus and northern analysis showed that the disruption strain produced a truncated pacc mrna of 2.2 kb (as ...19968709960
purification and partial characterization of the high and low molecular weight form (s- and f-form) of invertase secreted by aspergillus nidulans.two forms of secreted invertase have been purified from aspergillus nidulans by ion-exchange and gel-filtration chromatography. s-invertase gave a single, broad, glycoprotein band on page and sds-page corresponding in size to 185 and 78 kda, respectively, compared with 94 and 110 kda for f-invertase. the carbohydrate of s-invertase contained mainly mannose (14%) and less galactose (5%) whereas the f-form yielded mainly galactose (29%) and less mannose (12%). three sharp bands of enzymically acti ...19968814228
suppression and enhancement of the aspergillus nidulans medusa mutation by altered dosage of the bristle and stunted genes.asexual reproduction in aspergillus nidulans is characterized by the orderly differentiation of multicellular reproductive structures (conidiophores) and chains of uninucleate conidia (spores). mutations in the developmental modifier medusa (meda) result in aberrant conidiophores with branching chains of reiterated reproductive cells (metulae), delayed conidial differentiation and frequent reinitiation of secondary conidiophores. we show that incorrect morphology is in part a consequence of modi ...19968722771
saccharomyces cerevisiae tec1 is required for pseudohyphal growth.diverse eukaryotic organisms share developmental transcription factors with homologous dna-binding domains. we showed that the developmental regulator abaa, a member of the atts/tea (abaa, tef-1, tec1, scalloped/tef-1, tec1, abaa) class of transcription factors of the filamentous fungus aspergillus nidulans, induces pseudohyphal development in the yeast saccharomyces cerevisiae. the s. cerevisiae homologue of abaa, tec1p, is required for this morphological transition. we provide evidence that te ...19968730867
multiple copies of mate elements support autonomous plasmid replication in aspergillus nidulans.the ama1 sequence is an efficient plasmid replicator and transformation enhancer in aspergillus nidulans. it comprises two long perfect inverted repeats (mate elements) flanking a short, unique, central spacer. subclone analysis indicates that the complete inverted duplication, but not the unique central spacer, is necessary for efficient plasmid replication. the smallest fragments able to affect transformation efficiency lie within the at-rich portions of the inverted repeats. we demonstrate th ...19968733240
a newly identified gene cluster in aspergillus nidulans comprises five novel genes localized in the alc region that are controlled both by the specific transactivator alcr and the general carbon-catabolite repressor crea.ethanol-utilization in aspergillus nidulans is mediated by alcohol dehydrogenase i and aldehyde dehydrogenase encoded by alca and alda, respectively. both genes are under the transcriptional control of the specific activator alcr and the general carbon catabolite repressor crea. the alcr and alca genes are closely linked in chromosome vii; alda is located in chromosome viii. we have identified five other transcripts that are expressed from the same genomic region as alca and alcr. they are induc ...19968736527
characterization of a penicillium chrysogenum gene encoding a pacc transcription factor and its binding sites in the divergent pcbab-pcbc promoter of the penicillin biosynthetic cluster.previous work established that ph regulation of gene expression in aspergillus nidulans, a major determinant of penicillin biosynthesis, is mediated by the zinc-finger transcription factor pacc, an activator of transcription of the isopenicillin n synthase gene. we characterize here the pacc gene from the efficient penicillin producer penicillium chrysogenum, which functionally complements an a. nidulans pacc null mutation. it encodes a 641-residue polypeptide showing 64% identify to a. nidulans ...19968736532
the secondary structure and phylogenetic relationship deduced from complete nucleotide sequence of mitochondrial small subunit rrna in yeast hansenula wingei.we have accomplished the nucleotide sequence of the 1537 bp mitochondrial gene coding for small subunit (ssu) rrna of yeast hansenula wingei, and also determined the 5'- and 3'-termini by s1 nuclease mapping. eight universally conserved (u) elements of the ssu rrna were identified. comparison of u regions among five fungal mitochondrial ssu rrna shows the striking similarity between h. wingei and saccharomyces cerevisiae. the construction of the secondary structure revealed a core structure simi ...19968752867
expression of the sclerotinia sclerotiorum polygalacturonase pg1 gene: possible involvement of crea in glucose catabolite repression.northern-blot analysis of rna isolated from sclerotinia sclerotiorum grown on either glucose or polygalacturonate as the sole carbon source showed that pg1, encoding a neutral polygalacturonase, was not expressed during growth in both media. in contrast, transcripts of this gene were detected during infection of sunflower germlings. analysis of the promoter sequence revealed a number of cis-acting sequences known to regulate the expression of many fungal promoters. protein-dna-binding experiment ...19968753653
translational initiation competence, 'leaky scanning' and translational reinitiation in area mrna of aspergillus nidulans.(1) aug codons that either permit or prevent 'leaky scanning' of mrna encoding area, the transcriptional activator mediating nitrogen metabolite repression in aspergillus nidulans, have been identified. the consensus context for a strong initiation codon (i.e. one preventing 'leaky scanning') derived from this work is gxx aug c/ucx. however, aug codons which do not conform to this consensus are nevertheless able to initiate translation. (2) translational reinitiation can occur within area mrna, ...19968830259
the tama gene of aspergillus nidulans contains a putative zinc cluster motif which is not required for gene function.expression of many nitrogen catabolic enzymes is controlled by nitrogen metabolite repression in aspergillus nidulans. although the phenotypes of tama mutants have implicated this gene in nitrogen regulation, its function is unknown. we have cloned the tama gene by complementation of a new tama allele. the tama sequence shares significant homology with the uga35/dal81/durl gene of saccharomyces cerevisiae. in vitro mutagenesis of sequences encoding a putative zinc cluster dna binding domain indi ...19968655534
[test for the effects of mutagenic toxic fungal metabolites originating from municipal landfill sites].the purpose of the study is to assess the mutagenic effect of mycotoxins produced by moulds growing on municipal landfill sites. mutagenicity of toxic fungal metabolites was determined by the salmonella plate incorporation assay with two strains of bacteria: ta98 and ta100, with and without metabolic activation. the results obtained indicate that there is a severe hazard caused by these mycotoxins detected main by ta98 with metabolic activation. the most mutagenic mixture of mycotoxins acting di ...19968656997
isolation of opportunistic fungi from bronchoalveolar lavage of compromised hosts in isfahan, iran.in this study, bronchoalveolar lavage (bal) specimens from 247 immunocompromised patients were investigated for the incidence of opportunistic fungi. in the direct examination and culture of the specimens, 5 (2.02%) of filamentous fungi and 55 (22.26%) yeasts were isolated and identified as follows: aspergillus fumigatus (2), a. terreus (1), a. nidulans (1), mucor sp. (1), candida albicans (29), c. glabrata (3), c. parapsilosis (1), trichosporon beigelii (1), candida sp. (13) and unknown yeasts ...19968751826
identification of a new antifungal target site through a dual biochemical and molecular-genetics approach.the target site of the antifungal compound ly214352 [8-chloro-4-(2-chloro-4-fluorophenoxy) quinoline] has been identified through a dual biochemical and molecular-genetics approach. in the molecular-genetics approach, a cosmid library was prepared from an aspergillus nidulans mutant that was resistant to ly214352 because of a dominant mutation in a single gene. a single cosmid (6a6-6) that could transform an ly214352-sensitive strain of a. nidulans to ly214352-resistance was isolated from the li ...19968660469
phylogenetic analysis of the isopenicillin-n-synthetase horizontal gene transfer.a phylogenetic study of the isopenicillin-n-synthetase (ipns) gene sequence from prokaryotic and lower eukaryotic producers of beta-lactam antibiotics by means of a maximum-likelihood approach has been carried out. after performing an extensive search, rather than invoking a global molecular clock, the results obtained are best explained by a model with three rates of evolution. grouped in decreasing order, these correspond to a. nidulans and then to the rest of the eukaryotes and prokaryotes, r ...19968662005
transformation of the plant pathogenic fungus, rhynchosporium secalis.the barley leaf scald fungus, rhynchosporium secalis, was transformed to hygromycin-b and phleomycin resistance using the hph gene from e. coli and the ble gene from streptoalloteichus hindustanus under the control of aspergillus nidulans promoter and terminator sequences. plasmid dna was introduced into fungal protoplasts by peg/cacl2 treatment. transformation frequencies varied from 59 to 493 transformants per 10 microg of dna and 5 x 10(7) protoplasts. the antibiotic-resistant phenotype appea ...19968662199
characterization of the aspergillus parasiticus niad and niia gene cluster.the nitrate reductase gene (niad) and nitrite reductase gene (niia) of aspergillus parasiticus are clustered and are divergently transcribed from a 1.6-kb intergenic region (niad-niia). the deduced aminoacid sequence of the a. parasiticus nitrate reductase demonstrated a high degree of homology to those of other aspergillus species, as well as to leptosphaeria maculans, fusarium oxysporum, gibberella fujikuroi and neurospora crassa, particularly in the cofactor-binding domains for molybdenum, he ...19968662212
identification, cloning and analysis of the aspergillus niger gene pacc, a wide domain regulatory gene responsive to ambient ph.a wide domain regulatory gene implicated in modulating gene expression in response to ambient ph has been cloned and sequenced from the industrially useful filamentous fungus aspergillus niger. this gene, pacc, is able to restore a pacc+ phenotype to a. nidulans paccc11 and paccc14 mutants with respect to extent of conidiation, conidial pigment intensity and acid phosphatase regulation. the pacc gene of a. niger comprises three exons, encodes a three-zinc-finger protein of 677 amino acids, and s ...19968602152
a human peptidyl-prolyl isomerase essential for regulation of mitosis.the nima kinase is essential for progression through mitosis in aspergillus nidulans, and there is evidence for a similar pathway in other eukaryotic cells. here we describe the human protein pin1, a peptidyl-prolyl cis/trans isomerase (ppiase) that interacts with nima. ppiases are important in protein folding, assembly and/or transport, but none has so far been shown to be required for cell viability. pin1 is nuclear ppiase containing a ww protein interaction domain, and is structurally and fun ...19968606777
comparative analysis of the qutr transcription repressor protein and the three c-terminal domains of the pentafunctional arom enzyme.the arom protein is a pentadomain protein catalysing steps two to six in the prechorismate section of the shikimate pathway in microbial eukaryotes. on the basis of amino acid sequence alignments and the properties of mutants unable to utilize quinic acid as a carbon source, the arom protein has been proposed to be homologous throughout its length with the proteins regulating transcription of the genes necessary for quinate catabolism. the qutr transcription repressor protein has been proposed t ...19968611179
transformation of aspergillus nidulans by rna from rat macrophages stimulated with lipopolysaccharide.exogenous rna molecules can be incorporated into eukaryotic cells and can exert a variety of biological effects. we have previously described a model system for correcting genetic alterations of an aspergillus nidulans mutant using homologous rna and this phenomenon was named retrotransformation. in the present study, the retrotransformation of a. nidulans was performed with heterologous rna which was extracted from rat macrophages stimulated with lipopolysaccharide (lps). protoplasts of a. nidu ...19968696260
flug and flba function interdependently to initiate conidiophore development in aspergillus nidulans through brla beta activation.the aspergillus nidulans flug gene is necessary for the synthesis of a small diffusible factor that is required for the endogenously regulated induction of asexual sporulation that takes place during the development of an air-exposed colony. previous work established that flug is present at nearly constant levels throughout the aspergillus life cycle, leading to the hypothesis that flug factor is constitutively produced and development initiates after its concentration surpasses a fixed threshol ...19968617205
the 3-phosphoglycerate kinase gene of the yeast yarrowia lipolytica de-represses on gluconeogenic substrates.we have isolated the 3-phosphoglycerate kinase (pgk) gene of the yeast yarrowia lipolytica by probing a genomic library with a pcr fragment amplified with primers deduced from two highly conserved regions of various pgks. it is a unique sequence encoding a polypeptide of 417 residues with extensive homology to other pgks, especially to that of aspergillus nidulans (76% identity). the expression of the y. lipolytica pgk1 gene proved to be higher on gluconeogenic substrates than on glycolytic ones ...19968625424
evidence for slta1 as a salt-sensitive allele of the arginase gene (agaa) in the ascomycete aspergillus nidulans.strains of aspergillus nidulans carrying the slta1 mutation, conferring sensitivity to kcl and nacl, also showed an arginine-sensitive phenotype whereby concentrations of the l-amino acid at or above 10 mm were toxic to growth. sexual progeny of a cross between a slta1 mutant and a wild-type strain showed a co-segregation of salt and arginine sensitivity. similarly, revertants to salt tolerance showed a loss of arginine sensitivity as did slta1 strains that were transformed with a cosmid carryin ...19968625426
endoglucanase ii (egii) of penicillium janthinellum: cdna sequence, heterologous expression and promotor analysis.the cdna coding for the endoglucanase egii of p. janthinellum was cloned and sequenced. the open reading frame comprises 1230 nucleotides and the deduced amino-acid sequence shows an overall homology of 63% with the t. reesei egl2. the cellulose-binding domain of egii represents a typical member of the a family of cellulases. the egl2 gene is only induced by cellulose or cellobiose and not by sophorose. a promotor fragment including 1 kb was cloned and sequenced. three major transcription startp ...19968625430
mutations affecting extracellular protease production in the filamentous fungus aspergillus nidulans.the extracellular proteases of aspergillus nidulans are known to be regulated by carbon, nitrogen and sulphur metabolite repression. in this study, a mutant with reduced levels of extracellular protease was isolated by screening for loss of halo production on milk plates. genetic analysis of the mutant showed that it contains a single, recessive mutation, in a gene which we have designated xpre, located on chromosome vi. the xpre1 mutation affected the production of extracellular proteases in re ...19968628232
purification and characterization of mitochondrial ribonuclease p from aspergillus nidulans.mitochondrial ribonuclease (rnase) p from aspergillus nidulans was purified to near homogeneity using whole-cell extract as the starting material. a 4400-fold purification with a yield of 5.2% was achieved by ammonium sulfate fractionation, heat treatment, and five types of column chromatography, including trna-affinity column chromatography. this enzyme, which has a molecular mass of 232 kda determined by glycerol gradient sedimentation analysis, appears to be composed of seven polypeptides and ...19968631344
the rna component of mitochondrial ribonuclease p from aspergillus nidulans.several rna molecules that copurified with aspergillus nidulans mitochondrial ribonuclease (rnase) p were identified [lee, y c., lee, b. j., hwang, d. s. & kang, h. s. (1996) eur j. biochem. 235, 289-296], and their partial sequences were determined. using an oligonucleotide probe, we cloned and mapped the gene encoding this putative rna component of rnase p (rnase p-rna), situated between urfa3 (unidentified reading frame a3) and coba (apocytochrome b) genes in the mitochondrial genome of a. ni ...19968631345
twenty-five coregulated transcripts define a sterigmatocystin gene cluster in aspergillus nidulans.sterigmatocystin (st) and the aflatoxins (afs), related fungal secondary metabolites, are among the most toxic, mutagenic, and carcinogenic natural products known. the st biosynthetic pathway in aspergillus nidulans is estimated to involve at least 15 enzymatic activities, while certain aspergillus parasiticus, aspergillus flavus, and aspergillus nomius strains contain additional activities that convert st to af. we have characterized a 60-kb region in the a. nidulans genome and find it contains ...19968643646
wild chromosomal variants in aspergillus nidulans.pulsed-field gel electrophoresis and a chromosome-specific cosmid dna library were used to determine the karyotypes of wild-type aspergillus nidulans isolates from around the world. overall, little structural variation was found, with a few major exceptions. one isolate possessed a non-essential b-chromosome of about 1.0 million base pairs (mb). another isolate had undergone a non-reciprocal translocation of about 1.6 mb of chromosome vi onto chromosome viii. other than these chromosomal differe ...19968595677
in vitro activity of 1,3-beta-d-glucan synthase requires the gtp-binding protein rho1.in the yeast saccharomyces cerevisiae, the family of rho genes are implicated in the control of morphogenetic events although the molecular targets of these gtp-binding proteins remain largely unknown. the activity of 1,3-beta-d-glucan synthase, the product of which is essential for cell wall integrity, is regulated by a gtp-binding protein, which we here present evidence to be rho1p. rho1p was found to copurify with fks1p, a glucan synthase subunit, in preparations of the enzyme purified by pro ...19968662910
cata, a new aspergillus nidulans gene encoding a developmentally regulated catalase.aspergillus nidulans asexual sporulation (conidiation) is a model system for studying gene regulation and development. the can5 cdna is one of several clones isolated based on transcript induction during conidiation. here we present the molecular characterization of its corresponding gene, demonstrating that it encodes a developmentally regulated catalase, designated cata. the cata 744-amino-acid-residue polypeptide shows significant identity to other catalases. its similarity to prokaryotic cat ...19968598056
control of metabolic flux through the quinate pathway in aspergillus nidulans.the quinic acid ulitization (qut) pathway in aspergillus nidulans is a dispensable carbon utilization pathway that catabolizes quinate to protocatechuate via dehydroquinate and dehydroshikimate(dhs). at the usual in vitro growth ph of 6.5, quinate enters the mycelium by means of a specific permease and is converted into pca by the sequential action of the enzymes quinate dehydrogenase, 3-dehydroquinase and dhs dehydratase. the extent of control on metabolic flux exerted by the permease and the t ...19968670107
characterization of the ugata gene of ustilago maydis, isolated by homology to the gata gene of aspergillus nidulans.a gene encoding a putative gaba aminotransferase (ugata) was isolated from the basidiomycete ustilago maydis via heterologous hybridization to the gaba aminotransferase gene (gata) of aspergillus nidulans . the derived amino-acid sequence of ugata shows strong identity throughout the protein to the gaba aminotransferase enzymes from a. nidulans and saccharomyces cerevisiae. northern analysis in u. maydis indicated that the ugata transcript is inducible by the omega-amino acids gaba and beta-alan ...19968598057
quantitative analysis of gene expression in sexual structures of aspergillus nidulans by sequencing of 3'-directed cdna clones.we constructed a 3'-directed cdna library of cleistothecia and hülle cells of aspergillus nidulans to examine gene expression patterns of the sexual structures and to have probes necessary to isolate sexual structure-specific genes. sequencing of 360 randomly selected cdna clones yielded 272 expressed sequence tags (ests), most of which probably represent frequently or less expressed genes in sexual structures of a. nidulans. among the 272 ests, 33 ests (87 cdna clones) appeared more than once a ...19968674973
conservation of structure and function of the aflatoxin regulatory gene aflr from aspergillus nidulans and a. flavus.under limiting growth conditions, aspergillus nidulans produces a carcinogenic secondary metabolite related to aflatoxin and called sterigmatocystin (st). the genes for st biosynthesis are co-ordinately regulated and are all found within an approximately 60-kilobase segment of dna. one of the genes within this region is predicted to encode a cx2cx6cx6cx2cx6cx2 zinc binuclear cluster dna-binding protein that is related to the aspergillus flavus and aspergillus parasiticus aflatoxin regulatory gen ...19968662194
domain structure and function within the quta protein of aspergillus nidulans: implications for the control of transcription.quta is a positively acting regulatory protein that regulates the expression of the eight genes comprising the quinic acid utilization gene (qut) gene cluster in aspergillus nidulans. it has been proposed that the quta protein is composed of two domains that are related to the n-terminal two domains-dehydroquinate (dhq) synthase and 5-enolpyruvyl shikimate-3-phosphate (epsp) synthase-of the pentadomain arom protein. the arom protein is an enzyme catalysing five consecutive steps in the shikimate ...19968581174
nitrogen metabolite signalling involves the c-terminus and the gata domain of the aspergillus transcription factor area and the 3' untranslated region of its mrna.area is a gata transcription factor which mediates nitrogen metabolite repression in aspergillus nidulans in response to intracellular glutamine levels. we have identified and localized three elements important to modulation of area function: a region of 13 residues within the dna-binding gata domain which forms a putative extended loop structure, the 12 c-terminal residues, and sequences within a 218 nucleotide region of the 3' utr. the 12 c-terminal residues are also required for transcription ...19968654376
mutational analysis of the c-terminal region of area, the transcription factor mediating nitrogen metabolite repression in aspergillus nidulans.in aspergillus nidulans the positive-acting, wide domain regulatory gene area mediates nitrogen metabolite repression. previous analysis demonstrated that the c-terminal 153 residues of the area product (area) are inessential for at least partial expression of most genes subject to regulation by area. paradoxically, arear2, a -1 frameshift replacing the wild-type 122 c-terminal residues with a mutant peptide of 117 amino acids, leads to general loss of function. to determine the basis for the ar ...19968569680
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