PMID(sorted descending)
glucose-induced inactivation of isocitrate lyase in aspergillus nidulans.the existence of a second mechanism of catabolite control of isocitrate lyase of aspergillus nidulans, in addition to the carbon catabolite repression phenomenon recently reported was analysed. isocitrate lyase was rapidly and specifically inactivated by glucose. the inactivation was irreversible at all stages in the presence of cycloheximide, showing that reactivation depends on de novo protein synthesis. in addition, analysis of glucose-induced inactivation of isocitrate lyase in a cread-30 st ...19947872837
yeast proteins can activate expression through regulatory sequences of the amds gene of aspergillus nidulans.the upstream regulatory region of the amds gene of aspergillus nidulans contains a ccaat sequence known to be important in setting both basal and depressed levels of expression. we have investigated whether the ccaat-binding hap2/3/4 complex of the yeast saccharomyces cerevisiae can recognise this sequence in an amds context. sequences from the 5' region of amds were cloned in front of the cyc1-lacz fusion gene bearing a minimal promoter and transformed into wild-type and hap2 strains of yeast. ...19957862093
gene inactivation in the plant pathogen glomerella cingulata: three strategies for the disruption of the pectin lyase gene pnla.the feasibility of performing routine transformation-mediated mutagenesis in glomerella cingulata was analysed by adopting three one-step gene disruption strategies targeted at the pectin lyase gene pnla. the efficiencies of disruption following transformation with gene replacement- or gene truncation-disruption vectors were compared. to effect replacement-disruption, g. cingulata was transformed with a vector carrying dna from the pnla locus in which the majority of the coding sequence had been ...19957862090
molecular similarity matrices and quantitative structure-activity relationships: a case study with methodological implications.recently, statistical analysis of molecular similarity matrices has been applied to the quantitative structure-activity relationship (qsar) analysis of a number of molecular series. this paper addresses a number of methodological issues relative to the similarity matrices. a series of halogenated aliphatic hydrocarbons, for which the mutation (aneuploidy) induction ability had previously been determined, was used as test bench. the chemical information carried by the similarity matrices was show ...19957861411
myoa of aspergillus nidulans encodes an essential myosin i required for secretion and polarized growth.we have identified and cloned a novel essential myosin i in aspergillus nidulans called myoa. the 1,249-amino acid predicted polypeptide encoded by myoa is most similar to the amoeboid myosins i. using affinity-purified antibodies against the unique myosin i carboxyl terminus, we have determined that myoa is enriched at growing hyphal tips. disruption of myoa by homologous recombination resulted in a diploid strain heterozygous for the myoa gene disruption. we can recover haploids with an intact ...19957860631
aspergillus nidulans apsa (anucleate primary sterigmata) encodes a coiled-coil protein required for nuclear positioning and completion of asexual development.many fungi are capable of growing by polarized cellular extension to form hyphae or by isotropic expansion to form buds. aspergillus nidulans anucleate primary sterigmata (apsa) mutants are defective in nuclear distribution in both hyphae and in specialized, multicellular reproductive structures, called conidiophores. apsa mutations have a negligible effect on hyphal growth, unlike another class of nuclear distribution (nud) mutants. by contrast, they almost completely block entry of nuclei into ...19957860626
transformation of botrytis cinerea with the hygromycin b resistance gene, hph.a transformation method has been developed for the phytopathogenic fungus botrytis cinerea. protoplasts were transformed with pan7-1 plasmid carrying the escherichia coli hygromycin phosphotransferase gene (hph), conferring hygromycin b resistance, downstream from an aspergillus nidulans promoter. molecular analysis, showed that transformation resulted in an integration of the plasmid into different regions of the b. cinerea genome and occurred through non-homologous recombination. the frequency ...19947859308
additive action of partial heterokaryon incompatibility (partial-het) genes in aspergillus nidulans.we have observed partial heterokaryon-incompatibility reactions in combinations of field isolates of a. nidulans. we have demonstrated that partial heterokaryon incompatibility is genetically controlled by genes (partial-het genes) operating in the same manner as the previously-described het genes. our results also reveal that partial-het genes can act additively in causing heterokaryon incompatibility and that partial heterokaryon incompatibility is not a barrier to the horizontal transfer of a ...19947859306
molecular karyotype alterations induced by transformation in aspergillus nidulans are mitotically stable.clamped homogeneous electric field (chef)-gel electrophoresis was used to define the electrophoretic molecular karyotype of aspergillus nidulans strain oc-1 before and after protoplast-based genetic transformation. the transforming dna caused alterations in the molecular karyotypes in all transformants examined. rather dramatic changes were observed in karyotypes, including apparent chromosome loss, massive size alterations, and the appearance of large chromosomes. changes in molecular karyotype ...19947859304
heterologous transformation of zalerion arboricola.a heterologous dna-mediated transformation system was developed for the pneumocandin-producing fungus z. arboricola that was based on either conferral of hygromycin b resistance or complementation of a nitrate reductase mutant. hygromycin-resistant transformants were selected with plasmid pcsn43 which contains the e. coli hygromycin b phosphotransferase gene under the control of aspergillus nidulans trpc transcription signals. transformation frequencies were about four transformants per microgra ...19947859303
molecular genetics of aspergillus pathogenicity.aspergillus fumigatus is the most frequent cause of invasive pulmonary aspergillosis (ipa), a life-threatening disease of immunosuppressed patients. in addition to a number of general physiological attributes of this fungus, it has been suggested that extracellular elastase and toxins might facilitate its growth in lung tissue. we have investigated the roles of two extracellular proteins, an alkaline protease with elastase activity (afalp), and the ribotoxin restrictocin in murine models of ipa. ...19947847892
expression of genes and processing of enzymes for the biosynthesis of penicillins and cephalosporins.the genes pcbab, pcbc and pende encoding the enzymes (alpha-aminoadipyl-cysteinyl-valine synthetase, isopenicillin n synthase and isopenicillin n acyltransferase, respectively) involved in the biosynthesis of penicillin have been cloned from penicillin chrysogenum and aspergillus nidulans. they are clustered in chromosome i (10.4 mb) of p. chrysogenum, in chromosome ii of penicillium notatum (9.6 mb) and in chromosome vi (3.0 mb) of a. nidulans. each gene is expressed as a single transcript from ...19947847890
regulatory circuits of the amds gene of aspergillus nidulans.the amds gene codes for an acetamidase enzyme that hydrolyses acetamide to acetate and ammonium thus providing a. nidulans with a source of carbon and nitrogen. the exceptionally favourable genetics of this system combined with molecular analysis have enabled many regulatory circuits affecting amds to be identified genetically. characterization of the regulatory genes and the definition of the cis-acting sites involved have been done using both in vivo and in vitro mutagenesis. recent results on ...19947847883
nitrogen regulation in fungi.nitrogen regulation has been extensively studied in fungi revealing a complex array of interacting regulatory genes. the general characterisation of the systems in aspergillus nidulans and neurospora crassa shall be briefly described, but much of this paper will concentrate specifically on the recent molecular characterisation of area, the principle regulatory gene from a. nidulans which mediates nitrogen metabolite repression. three areas shall be explored in detail, firstly the dna binding dom ...19947847882
the vitamin d3 hydroxylase-associated protein is a propionamide-metabolizing amidase enzyme.previously we isolated a novel protein that coimmunoprecipitates with the 1,25-dihydroxyvitamin d3-24r-hydroxylase and 25-hydroxyvitamin d3-1 alpha-hydroxylase. this kidney-specific protein found in the inner membrane of mitochondria is named the vitamin d3 hydroxylase-associated protein (vdhap). to determine a putative function for this protein, an extensive computer search of the deduced amino acid sequence of vdhap was performed. a blast homology search identified amino acid residues 133 thro ...19957840608
two new genes involved in signalling ambient ph in aspergillus nidulans.two new genes, palh and pali, where mutations mimic the effects of acidic growth ph have been identified in aspergillus nidulans. a palh mutation is phenotypically indistinguishable from mutations in the pala, palb, palc, and palf genes, whereas pali mutations differ only in that they allow some growth at ph 8. mutations in pala, b, c, f, and h are epistatic to a pali mutation and the significance of this epistasis is discussed. additionally, pale and palb mutations have been shown to be allelic ...19947830727
overexpression of flba, an early regulator of aspergillus asexual sporulation, leads to activation of brla and premature initiation of development.aspergillus nidulans reproduces asexually by forming thousands of mitotically derived spores atop highly specialized multicellular organs termed conidiophores. we have identified a gene called flba (for fluffy low brla expression) that is required for initiation of a. nidulans conidiophore development. flba mutants form abnormal colonies that have a distinct fluffy phenotype characterized by tightly interwoven aerial hyphae that autolyse as the colony matures. the requirement for flba in conidio ...19947830576
heterologous expression of the cytotoxin restriction in aspergillus nidulans and aspergillus niger.the cdna clone of restrictocin was placed under the control of the glucoamylase promoter from aspergillus awamori and was transformed into aspergillus nidulans and aspergillus niger. site-specific changes were introduced into cdna constructs and these were transformed into a. nidulans. the secretion signal sequence was deleted from one form of the gene and three mutations introduced single amino acid substitutions into the protein. culture conditions were optimized for maximum expression levels ...19947827506
overexpression of two penicillin structural genes in aspergillus nidulans.we have placed two different penicillin structural genes from aspergillus nidulans, ipna (encoding isopenicillin n synthetase, ipns) and acya (encoding acyl-coa:6-aminopenicillanic acid acyltransferase, aat), under the control of the strong alca promoter [alca(p)]. single copies of these transcriptional fusions were targeted to the same chromosomal location and conditions have been worked out which simultaneously allow induction of the alca(p) and support penicillin biosynthesis. transcriptional ...19957823906
isolation and characterization of an aspergillus nidulans gene encoding an alkaline protease.we have cloned an aspergillus nidulans gene (prta) encoding an alkaline protease (alp) by probing an a. nidulans library with a fragment amplified from an aspergillus oryzae alp-encoding gene. the nucleotide (nt) sequence of prta was determined. the structure of prta is similar to that of the a. oryzae alp-encoding gene. the prta gene is composed of four exons which are separated by three introns of 59, 57 and 54 nt. the deduced amino acid sequence of the prta product shows a high degree of simi ...19947821793
direct analysis of native and chimeric gata specific dna binding proteins from aspergillus aspergillus nidulans the regulatory gene area is responsible for mediating nitrogen metabolite repression. the area product (area) represents an example of the gata family of dna binding proteins, which are characterised by the presence of a gata domain consisting of a zinc finger within a highly conserved region of 52 amino acids. among the other transcription factors included in this family is the principal erythroid transcription factor, gata-1, which contains two gata domains. in order to ...19947816601
crystal structure of isopenicillin n synthase is the first from a new structural family of enzymes.penicillin antibiotics are all produced from fermentation-derived penicillins because their chemical synthesis is not commercially viable. the key step in penicillin biosynthesis, in which both the beta-lactam and thiazolidine rings of the nucleus are created, is mediated by isopenicillin n synthase (ipns), which binds ferrous iron and uses dioxygen as a cosubstrate. in a unique enzymatic step, with no chemical precedent, ipns catalyses the transfer of four hydrogen atoms from its tripeptide sub ...19957791906
a mutualistic fungal symbiont of perennial ryegrass contains two different pyr4 genes, both expressing orotidine-5'-monophosphate decarboxylase.a fragment of the claviceps purpurea pyr4 gene, encoding orotidine-5'-monophosphate decarboxylase (omp decarboxylase), was used to screen a genomic library from an isolate of a fungus, acremonium sp. (designated lp1), which grows as an endophyte in perennial ryegrass (lolium perenne). three positive clones, lambda mc11, lambda mc12 and lambda mc14, were isolated. two of these clones, lambda mc12 and lambda mc14, were overlapping clones from the same locus, while lambda mc11 was from a different ...19957789808
a mini-promoter lacz gene fusion for the analysis of fungal transcription control sequences.a system for the in vivo analysis of fungal transcription control sequences, based on a mini-promoter, was designed. the mini-promoter, providing all sequences necessary and sufficient for transcription initiation, was derived from the aspergillus nidulans gpda promoter region. transcription initiation was not affected by the introduction of transcription control sequences directly upstream from the mini-promoter. furthermore, the expression of the mini-promoter was not affected by wide-domain c ...19957789794
molecular cloning and analysis of nre, the major nitrogen regulatory gene of penicillium chrysogenum.we have isolated the penicillium chrysogenum nre gene which is homologous to the major nitrogen regulatory genes area from aspergillus nidulans and nit-2 from neurospora crassa. overall, nre shows 60% identity to area and 30% identity to nit-2 at the amino-acid level. the gene encodes a protein of 835 amino-acid residues and contains a single cys2/cys2-type zinc finger with an adjacent basic region and a putative acidic activation region. in the dna-binding domain, 98% of the amino-acid residues ...19957788718
sequence analysis of the aspergillus nidulans pectate lyase pela gene and evidence for binding of promoter regions to crea, a regulator of carbon catabolite repression.the nucleic acid and deduced amino-acid sequences of the pectate lyase gene (pela) from aspergillus nidulans are presented. the pela gene contains two short introns, 68 and 49 bp in length, and encodes a peptide of 326 amino acids. five transcriptional start sites are clustered between 65 and 79 bp upstream of the start codon as determined by primer extension. comparison of the amino-acid sequences of pectate or pectin lyases from bacteria, fungi and plants revealed less than 30% overall identit ...19957788717
a heuristic approach to the analysis of enzymic catalysis: reaction of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-alpha-aminobutyrate and delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-allylglycine catalyzed by isopenicillin n synthase isozymes.isopenicillin n synthase (ipns) catalyzes the oxidative cyclization of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine to isopenicillin n. it is proposed that the multiple products produced from certain substrate analogues result from pathway branching after formation of a ferryl oxene intermediate. we have been interested in ascertaining the reasons for multiple product formation. one possibility is that the products are predisposed toward formation once the beta-lactam ring and the ferryl ox ...19957779800
the genetics of nuclear migration in fungi. 19957779511
a case of chronic necrotizing pulmonary aspergillosis due to aspergillus nidulans.a 55-year old man without immunosuppression clinically showed a coin lesion in the right lower lung on the chest radiographs. aspergillus nidulans was isolated and identified in both trans-bronchial lung biopsy specimen and resected tissue. the specimens revealed characteristics of chronic necrotizing pulmonary aspergillosis pathologically. very few reports on cases of pulmonary aspergillosis due to a. nidulans exist, and we were not able to find any reports of similar cases. this case may be th ...19947777037
characterization of a prolactin-inducible gene, clone 15, in t examine how prl regulates lymphocyte proliferation, a number of prl-activated genes were identified from a prl-dependent rat t lymphoma cell line, nb2. one of the downstream genes in the prl signaling cascade was identified as clone 15 (c15). prl stimulation of quiescent nb2 t cells results in the expression of a 1.7-kilobase c15 mrna, which reaches maximum levels between 8 and 10 h after stimulation. corresponding [3h]thymidine incorporation experiments show that the maximum level of c15 mrn ...19957776977
genes for beta-lactam antibiotic biosynthesis.the genes pcbab, pcbc and pende encoding enzymes involved in the biosynthesis of penicillin have been cloned from penicillium chrysogenum and aspergillus nidulans. they are clustered in chromosome i (10.4 mb) of p. chrysogenum, but they are located in chromosome ii of penicillium notatum (9.6 mb) and in chromosome vi (3.0 mb) of a. nidulans. expression studies have shown that each gene is expressed as a single transcript from separate promoters. enzyme regulation studies and gene expression anal ...19957771766
isolation and characterisation of genes for sulphate activation and reduction in aspergillus nidulans: implications for evolution of an allosteric control region by gene duplication.a region of the aspergillus nidulans genome carrying the sa and sc genes, encoding paps reductase and atp sulphurylase, respectively, was isolated by transformation of an sa mutant with a cosmid library. the genes were subcloned and their functions confirmed by retransformation and complementation of a. nidulans strains carrying sa and sc mutations. the physical distance of 2 kb between the genes corresponds to a genetic distance of 1 cm. while the deduced amino acid sequence of the sa gene prod ...19957770049
polarity of meiotic gene conversion is 5' to 3' within the niad gene of aspergillus nidulans.we have examined polarity of meiotic gene conversion in the niia-niad gene cluster of aspergillus nidulans in two-point crosses. the type and position of the mutations represented by the niad alleles and the correlation between the relative frequency of gene conversion and the physical position of these mutations were determined. we show that polarity of meiotic gene conversion is 5' to 3' (transcribed strand) within the niad gene. additional crosses involving a niia allele and a niad allele sho ...19957770039
extragenic suppressors of a dynein mutation that blocks nuclear migration in aspergillus nidulans.cytoplasmic dynein is a large molecular weight protein complex that functions as a microtubule-dependent, negative, end-directed "motor." mutations in nuda, which encodes the heavy chain of cytoplasmic dynein, inhibit nuclear migration in aspergillus nidulans. this paper describes the selection and characterization of extragenic suppressors of the nuda1 mutation preparatory to the identification of other proteins that interact directly or indirectly with the cytoplasmic dynein heavy chain. to fa ...19957768435
purification of a heat-stable chitin deacetylase from aspergillus nidulans and its role in cell wall extracellular chitin deacetylase activity has been purified to homogeneity from autolyzed cultures of aspergillus nidulans. this enzyme is an acidic glycoprotein with a pi of 2.75 and a 28% (wt/wt) carbohydrate content. the apparent m(r) of the enzyme estimated by sds/page and superose 12 (f.p.l.c.) was around 27,000. the enzyme had an optimum ph at 7.0 and was stable in the ph range 4.0-7.5. its optimum temperature of reaction was 50 degrees c, and it was stable from 30 degrees to 100 degree ...19957765883
antifungal effects of allium sativum (garlic) extract against the aspergillus species involved in otomycosis.otomycosis due to saprophytic keratolytic fungi represents a small percentage of clinical external otitis. although there are certain antibacterial and antifungal agents available, they usually are very caustic, potentially ototoxic and cannot be used if the ear drum is perforated. garlic is utilized as a folk medicine in many countries for its antimicrobial and other beneficial properties. in response to a lack of otic preparations, the authors studied the efficacy of garlic extracts against th ...19957765862
isolation of a chitin synthase gene (chsc) of aspergillus nidulans.we isolated a class i chitin synthase gene (chsc) from aspergillus nidulans. expression of this gene was confirmed by northern analysis and by sequencing of the pcr-amplified dna fragments from cdna. chsc disruptants showed no difference of morphology in the asexual cycle and no difference of growth rate compared to a wild-type strain.19947765719
genetic modification of an echinocandin b-producing strain of aspergillus nidulans to produce mutants blocked in sterigmatocystin biosynthesis.the production of echinocandin b (ecb), a lipopolypeptide used for chemical manufacture of the anti-candida agent cilofungin, was accomplished by fermentation using a strain of aspergillus nidulans. in addition to ecb, this fermentation also produces a significant amount of sterigmatocystin (st), a potent carcinogen structurally related to the aflatoxins. mutants blocked in the st biosynthetic pathway were created by genetic modification of the polyploid production strain c747. the following ste ...19947765669
isolation and characterization of two chitin synthase genes from aspergillus nidulans.two chitin synthase genes, designated chsa and chsb, were isolated from aspergillus nidulans with the saccharomyces cerevisiae chs2 gene as the hybridization probe. nucleotide sequencing showed that chsa and chsb encoded polypeptides consisting of 1013 and 916 amino acid residues, respectively; the hydropathy profiles of the enzymes were similar to those of other fungal chitin synthases. northern analysis indicated that both genes were transcribed, suggesting that cellular chitin in a. nidulans ...19947765508
development of a new transformant selection system for penicillium chrysogenum: isolation and characterization of the p. chrysogenum acetyl-coenzyme a synthetase gene (faca) and its use as a homologous selection marker.a new transformation system for the filamentous fungus penicillium chrysogenum is described, based on the use of the homologous acetyl-coenzyme a synthetase (faca) gene as a selection marker. acetate-non-utilizing (fac-) strains of p. chrysogenum were obtained by positive selection for spontaneous resistance to fluoroacetate. among these fac mutants putative faca strains were selected for a loss of acetyl-coenzyme a (coa) synthetase activity. the faca gene, coding for the enzyme acetyl-coa synth ...19937765289
sources of strains, vectors, libraries. 19947765150
media. 19947765149
gene symbols. 19947765148
linkage map and locus list. 19947765147
translational suppression. 19947765146
homologous recombination. 19947765145
vectors for genetic manipulation. 19947765143
carbon metabolism. 19947765142
penicillin biosynthesis. 19947765141
mitochondria. 19947765139
ribosomes. 19947765138
control of cell growth. 19947765137
sexual sporulation. 19947765136
genetic regulation of conidiation. 19947765135
regulation of gene expression by oxygen, phosphorus and ph. 19947765134
carbon catabolite repression. 19947765133
aspergillus nidulans as an experimental organism. 19947765132
nitrogen metabolite repression. 19947765131
the early history. 19947765130
sulphur metabolism. 19947765129
regulation of acetamide utilization. 19947765128
the proline utilisation pathway, history and beyond. 19947765127
the purine degradation pathway, genetics, biochemistry and regulation. 19947765126
control of metabolic flux in the shikimate and quinate pathways. 19947765125
inorganic nitrogen assimilation: molecular aspects. 19947765124
alcohol metabolism. 19947765123
development of a transformation system for trichoderma longibrachiatum and its use for constructing multicopy transformants for the egl1 efficient transformation system for the fungus trichoderma longibrachiatum has been developed. transformation was obtained both by electroporation and polyethyleneglycol treatment, using a plasmid carrying the escherichia coli hygromycin b phosphotransferase gene as a dominant selectable marker. the transformation frequency was 0.5 to 5 transformants/micrograms plasmid dna. transformation normally occurred by tandem integration of the transforming dna. a high percentage of the transformants w ...19947765105
expression of organophosphate hydrolase in the filamentous fungus gliocladium virens.the broad-spectrum organophosphate hydrolase (oph; ec encoded by the organophosphate-degrading gene (opd) from pseudomonas diminuta mg and flavobacterium sp. atcc 27551 possesses capabilities of both p-o bond hydrolysis (e.g. paraoxon) and p-f bond hydrolysis [e.g. sarin and diisopropylfluorophosphate (dfp)]. in the present study a 9.4-kb plasmid, pcl1, was used to transform the saprophytic fungus gliocladium virens. pcl1 was derived from pjs294 by placing the fungal promoter (prom1) fr ...19947764970
molecular cloning, expression and structure of the endo-1,5-alpha-l-arabinase gene of aspergillus niger.secretion of endo-1,5-alpha-l-arabinase a (abn a) by an aspergillus niger xylulose kinase mutant upon mycelium transfer to medium containing l-arabitol was immunochemically followed with time to monitor its induction profile. a cdna expression library was made from polya+ rna isolated from the induced mycelium. this library was immunochemically screened and one abn a specific clone emerged. the corresponding abna gene was isolated from an a. niger genomic library. upon southern blot analysis, a ...19937764386
molecular cloning and sequence analysis of the cellobiohydrolase i gene from trichoderma koningii g-39.the cellobiohydrolase i gene, cbh1, has been cloned from an enhanced cellulase-producing strain, trichoderma koningii g-39. sequence comparisons show that t. koningii cbh1 is identical to that of t. reesei with the exception of 6 bp--two causing silent substitutions in the coding region, three differing in one of the introns, and one in 5'-noncoding region. thus, it should encode an identical cbhi to that of t. reesei despite the differences in morphological characters of the two species. analys ...19947764306
cloning of the aspergillus niger gene encoding alpha-l-arabinofuranosidase a.using l-arabitol as an inducer, simple induction conditions were established that resulted in high-level expression of alpha-l-arabinofuranosidase a by an aspergillus niger d-xylulose kinase mutant strain. these conditions were adapted to construct a cdna expression library from which an alpha-l-arabinofuranosidase a cdna clone was isolated using specific antiserum. the corresponding gene encoding alpha-l-arabinofuranosidase a (abfa) was isolated from a genomic library and cloned into a high cop ...19937764056
a glucose-derepressed promoter for expression of heterologous products in the filamentous fungus aspergillus nidulans.we describe a putative binding sequence (gcggggc) for the glucose-responsive repressor protein crea at two positions upstream of the transcription start site of the alcohol dehydrogenase i (alca) gene of aspergillus nidulans. to positively identify the putative binding sites as crea-specific, the gcggggc blocks were mutated at five internal nucleotide positions to gtactac and reintroduced into the wild type alca promoter driving expression of the endogenous alcohol dehydrogenase i gene. this cre ...19937763860
substrate specificity and cell cycle regulation of the nek2 protein kinase, a potential human homolog of the mitotic regulator nima of aspergillus nidulans.the human nek2 protein kinase is the closest known mammalian relative of the mitotic regulator nima of aspergillus nidulans. the two kinases share 47% sequence identity over their catalytic domains and display a similar cell cycle-dependent expression peaking at the g2 to m phase transition. hence, it is attractive to speculate that human nek2 and fungal nima may carry out similar functions at the onset of mitosis. to study the biochemical properties and substrate specificity of human nek2 and c ...19957759549
purification and characterization of assembly-competent tubulin from aspergillus nidulans.we have developed a procedure for purifying assembly-competent tubulin from aspergillus nidulans. to our knowledge, this is the first report of the purification of assembly-competent tubulin from a filamentous fungus, and the procedure should be of great value in analyzing the large number of alpha- and beta-tubulin mutations that have been isolated and characterized in a. nidulans. our procedure consists of overproduction of alpha- and beta-tubulin, partial purification by ion-exchange chromato ...19957756266
genetic requirements for initiating asexual development in aspergillus nidulans.conidiation in the filamentous ascomycete aspergillus nidulans requires activation of brla, a well-characterized transcriptional regulator of genes that are induced specifically during asexual development. we have isolated and characterized developmental mutations in six loci, designated flug, flba, flbb, flbc, flbd, and flbe, that result in defective development and reduced brla expression. these mutants grow indeterminately to produce masses of aerial hyphae resulting in the formation of cotto ...19947750148
development of primer sets designed for use with the pcr to amplify conserved genes from filamentous ascomycetes.we constructed nine sets of oligonucleotide primers on the basis of the results of dna hybridization of cloned genes from neurospora crassa and aspergillus nidulans to the genomes of select filamentous ascomycetes and deuteromycetes (with filamentous ascomycete affiliations). nine sets of primers were designed to amplify segments of dna that span one or more introns in conserved genes. pcr dna amplification with the nine primer sets with genomic dna from ascomycetes, deuteromycetes, basidiomycet ...19957747954
evidence for a nima-like mitotic pathway in vertebrate cells.nima is essential for entry into mitosis in aspergillus nidulans. to examine whether there is a nima-like pathway in other eukaryotic cell cycles, we expressed nima and its dominant negative mutants in two different eukaryotic systems. in xenopus oocytes, nima induced germinal vesicle breakdown without activating mos, cdc2, or map kinase. in hela cells, nima induced premature mitotic events without activating cdc2, whereas the mutants caused a specific g2 arrest but did not block mutant cdc2t14a ...19957736593
purification of arginase from aspergillus nidulans.arginase (ec of aspergillus nidulans, the enzyme which enables the fungus to use arginine as the sole nitrogen source was purified to homogeneity. molecular mass of the purified arginase subunit is 40 kda and is similar to that reported for the neurospora crassa (38.3 kda) and saccharomyces cerevisiae (39 kda) enzymes. the native molecular mass of arginase is 125 kda. the subunit/native molecular mass ratio suggests a trimeric form of the protein. the arginase protein was cleaved and pa ...19947732765
how many 5s rrna genes and pseudogenes are there in aspergillus nidulans?we have estimated the number of 5s rrna genes in aspergillus nidulans using two-dimensional agarose gel electrophoresis and hybridization to appropriate probes, representing the 5'-halves, the 3'-halves of the 5s rrna sequence and a sequence found at the 3'-end of all known a. nidulans pseudogenes (block c). we have found 23 5s rrna genes, 15 pseudogenes consisting of the 5'-half of the 5s rrna sequence (of which 3 are flanked by block c) and 12 copies of block c which do not seem to be in the v ...19947732763
the sequence and binding specificity of uay, the specific regulator of the purine utilization pathway in aspergillus nidulans, suggest an evolutionary relationship with the ppr1 protein of saccharomyces cerevisiae.the uay gene codes for a transcriptional activator mediating the induction of a number of unlinked genes involved in purine utilization in aspergillus nidulans. here we present the complete genomic and cdna nucleotide sequence of this gene. the gene contains two introns. the derived polypeptide of 1060 residues contains a typical zinc binuclear cluster domain and shows a number of similarities with the ppr1 regulatory gene of saccharomyces cerevisiae. these similarities are most striking in the ...19957729421
molecular biological and biochemical aspects of fungal dimorphism. 19947722802
genetic and molecular characterization of a gene encoding a wide specificity purine permease of aspergillus nidulans reveals a novel family of transporters conserved in prokaryotes and aspergillus nidulans, loss-of-function mutations in the uapa and azga genes, encoding the major uric acid-xanthine and hypoxanthine-adenine-guanine permeases, respectively, result in impaired utilization of these purines as sole nitrogen sources. the residual growth of the mutant strains is due to the activity of a broad specificity purine permease. we have identified uapc, the gene coding for this third permease through the isolation of both gain-of-function and loss-of-function mutations. u ...19957721763
identification of developmental regulatory genes in aspergillus nidulans by overexpression.overexpression of several aspergillus nidulans developmental regulatory genes has been shown to cause growth inhibition and development at inappropriate times. we set out to identify previously unknown developmental regulators by constructing a nutritionally inducible a. nidulans expression library containing small, random genomic dna fragments inserted next to the alca promoter [alca(p)] in an a. nidulans transformation vector. among 20,000 transformants containing random alca(p) genomic dna fu ...19957713416
cellular effects of misscheduled brla, abaa, and weta expression in aspergillus nidulans.asexual sporulation in the fungus aspergillus nidulans is controlled, in part, by a central regulatory pathway composed of the brla, abaa, and weta genes. the coding region of each of these genes was fused, in frame, to the threonine-inducible alcohol dehydrogenase promotor then stably incorporated into the a. nidulans genome at the argb locus. misscheduled expression of each of these developmental genes interfered with normal growth and sporulation. expression of brla or abaa terminated vegetat ...19947704830
cdna structure and characterization of a kinesin-like protein from the silkworm bombyx mori.we have isolated a 1224 bp cdna clone from a bombyx mori embryonic cdna library which contains sequences homologous to the kinesin-like protein gene, ncd, which is required for distribution of chromosomes at meiosis in drosophila melanogaster females. this clone includes both a microtubule motor and the atp-binding domains found in kinesin-like proteins. the motor domain is classified in the group of the bimc and cut7, which have a role in spindle formation during mitosis of aspergillus nidulans ...19947704303
sequence around the 159 degree region of the bacillus subtilis genome: the pksx locus spans 33.6 kb.the nucleotide sequence of 20 kb contiguous to the pksx locus of bacillus subtilis was determined. six orfs were recognized, one of which extended for 13,341 nucleotides. their predicted products have significant similarities to proteins with known functions involved in the synthesis of polypeptides and polyketides or in fatty acid metabolism. at the nucleotide level, three regions with a high level of sequence identity (49-54%) to the aspergillus nidulans wa gene, responsible for the synthesis ...19957704258
production and characterization of sterigmatocystin.fourteen strains of aspergillus versicolor and 2 strains of a. nidulans were screened for sterigmatocystin (st) production on a semi-synthetic solid substrate by high performance liquid chromatography (hplc) analysis. two strains of a. versicolor producing st at 550.5 substrate and 1160.8 substrate were selected to inoculate 4 kg solid st-producing media. after 30 days stationary incubation at 28 degrees c in the dark, 2271.6 mg of pale-yellow needle-shaped crystals were isolated ...19947702759
an evaluation of the use of in vitro tubulin polymerisation, fungal and wheat assays to detect the activity of potential chemical aneugens.the test chemicals included in the ec aneuploidy project were evaluated for their ability to induce aneuploidy or aneuploidy related endpoints in assays using in vitro tubulin polymerisation, fungi and wheat. the results obtained demonstrated considerable qualitative and quantitative differences between the responses of the assays to the 10 test chemicals. fungal assays failed to respond to the potent mammalian spindle poisons colchicine and vinblastine and only three chemicals were positive in ...19937683381
nucleotide sequence of the large mitochondrial rrna gene of penicillium chrysogenum.the nucleotide sequence of a large rrna (1-rrna) gene and its flanking regions in the cloned fragments of mitochondrial (mt) dna from penicillium chrysogenum nrrl1951 (sekiguchi j., ohsaki, t., yamamoto, h., koichi, k. and shida, t. (1990) j. gen. microbiol. 136, 535-543) was determined and compared with those in aspergillus nidulans and neurospora crassa mitochondrial dnas. the p. chrysogenum mt 1-rrna gene has a 1678 bp intron which intervenes between a 2835 bp 5' exon and a 581 bp 3' exon, an ...19937680578
use of reporter genes to identify recessive trans-acting mutations specifically involved in the regulation of aspergillus nidulans penicillin biosynthesis genes.starting from three amino acid precursors, penicillin biosynthesis is catalyzed by three enzymes which are encoded by the following three genes: acva (pcbab), ipna (pcbc), and aat (pende). to identify trans-acting mutations which are specifically involved in the regulation of these secondary metabolism genes, a molecular approach was employed by using an aspergillus nidulans strain (axtii9) carrying acva-uida and ipna-lacz gene fusions integrated in double copies at the chromosomal argb gene. on ...19957677843
molecular characterization of a gene encoding a homogentisate dioxygenase from aspergillus nidulans and identification of its human and plant homologues.we report here the first characterization of a gene encoding a homogentisate dioxygenase, the aspergillus nidulans hmga gene. the hmga protein catalyzes an essential step in phenylalanine catabolism, and disruption of the gene results in accumulation of homogentisate in broths containing phenylalanine. hmga putatively encodes a 448-residue polypeptide (mr = 50,168) containing 21 histidine and 23 tyrosine residues. this polypeptide has been expressed in escherichia coli as a fusion to glutathione ...19957673153
the mig1 repressor from kluyveromyces lactis: cloning, sequencing and functional analysis in saccharomyces cerevisiae.sequence comparisons between saccharomyces cerevisiae scmig1 and aspergillus nidulans crea proteins allowed us to design two sets of degenerate primers from the conserved zinc finger loops. pcr amplification on kluyveromyces marxianus and k. lactis genomic dna yielded single products with sequences closely related to each other and to the corresponding regions of scmig1 and crea. the kimig1 gene of k. lactis was cloned from a genomic library using the k. marxianus pcr fragment as probe. kimig1 e ...19957672126
phylogenetic relationships of five species of aspergillus and related taxa as deduced by comparison of sequences of small subunit ribosomal rna.the nucleotide sequences of the genes encoding the 18s rrna of aspergillus flavus, a. nidulans, a. terreus and a. niger were elucidated and aligned to the sequences of a. fumigatus. in addition, the 18s rrna sequences of the v4-v9 region of morphologically similar filamentous fungi, e.g. penicillium chrysogenum, p. marneffei and paecilomyces variotii, were elucidated. phylogenetic analysis and comparison showed a very close intergeneric relationship of the genus aspergillus to species of the gen ...19957666299
molecular cloning and heterologous expression of the gene encoding dihydrogeodin oxidase, a multicopper blue enzyme from aspergillus terreus.aspergillus terreus dihydrogeodin oxidase (dhgo) is an enzyme catalyzing the stereospecific phenol oxidative coupling reaction converting dihydrogeodin to (+)- geodin. we previously reported the purification of dhgo from a. terreus and raised polyclonal antibody against dhgo. from the first cdna library constructed in lambda gt11 using mrna from 3-day-old mycelium of a. terreus, four clones were identified using anti-dhgo antibody, but all contained partial cdna inserts around 280 base pairs. th ...19957665560
crystallization and preliminary x-ray diffraction studies on recombinant isopenicillin n synthase from aspergillus nidulans.recombinant aspergillus nidulans isopenicillin n synthase was purified from an escherichia coli expression system. the apoenzyme in the presence of saturating concentrations of mncl2 could be crystallized by either macro- or microseeding, using the hanging drop vapor diffusion technique with polyethylene glycol 8000 as precipitant. the crystals (0.5-1.0 mm overall dimensions) diffract x-rays to at least 2.0 a resolution at synchrotrons and belong to space group p212121 with unit cell dimensions ...19957663335
genetic nomenclature guide. aspergillus nidulans. 19957660460
quantitation of oligohistidine fusion proteins using 63ni2+ chelation. 19957659532
the fusarium solani gene encoding kievitone hydratase, a secreted enzyme that catalyzes detoxification of a bean phytoalexin.among the antimicrobial phytoalexins produced by phaseolus vulgaris (french bean) is the prenylated isoflavonoid, kievitone. the bean pathogen, fusarium solani f. sp. phaseoli, secretes a glycoenzyme, kievitone hydratase (ec, which catalyzes conversion of kievitone to a less toxic metabolite. among f. solani strains, those that are highly virulent to p. vulgaris also produce kievitone hydratase constitutively, suggesting that the enzyme is a virulence factor. based on the n-terminal am ...19957655061
the aspergillus uvsh gene encodes a product homologous to yeast rad18 and neurospora uvs-2.the uvsh dna repair gene of aspergillus nidulans has been cloned by complementation of the uvsh77 mutation with a cosmid library containing genomic dna inserts from a wild-type strain. methylmethane sulfonate (mms)-resistant transformants were obtained on medium containing 0.01% mms, to which uvsh mutants exhibit high sensitivity. retransformation of uvsh77 mutants with the rescued cosmids from the mms-resistant transformants resulted in restoration of both uv and mms resistance to wild-type lev ...19957651340
dewa encodes a fungal hydrophobin component of the aspergillus spore anonymous cdna clone, pcan4, was shown previously to correspond to an mrna that accumulates preferentially during asexual sporulation of the filamentous fungus aspergillus nidulans. the peptide encoded by pcan4 is a fungal hydrophobin, a group of small, hydrophobic cell wall proteins. when the can4 gene was disrupted, conidia and conidiophores appeared to be normal, but sporulating colonies wetted more rapidly with detergent solutions than did the wild type. we renamed can4 dewa for the deter ...19957651135
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