PMID(sorted ascending)
sensitization to different species of aspergillus in bakery workers and general atopic population.six species of aspergillus predominant in the bakery environment--aspergillus flavus, a. fumigatus, a. nidulans, a. ochraceous, a. sydowi and a. versicolor--were studied for their role in causing type 1 hypersensitivity among bakery workers and atopic patients from the general population (pgp). antigenic extracts from the above species were prepared for in vivo and in vitro studies. the ief, sds-page, skin test, elisa and immunoblot techniques were performed to detect the biochemical- and clinic ...19989681123
purification and characterization of laccase ii of aspergillus nidulans.sexual development in aspergillus nidulans is a morphogenetic differentiation process triggered by internal and environmental signals. as a first step in analyzing the developmental pathway at the molecular level, laccase ii (ec, which is specifically expressed in early stages of fruitbodies, was isolated. the enzyme was purified to apparent homogeneity from a mutant strain (sms1) in which the sexual cycle dominates and the number of cleistothecia is increased tenfold. laccase ii was e ...19989683643
biochemical properties of the products of cytochrome p450 genes (pda) encoding pisatin demethylase activity in nectria haematococcapea plants produce the antibiotic (+)pisatin in response to infection by the fungus nectria haematococca, which can detoxify pisatin utilizing a cytochrome p450 monooxygenase called pisatin demethylase. genes (pda) have been identified that encode different whole-cell pda phenotypes that can be distinguished by the length of the lag period and the resulting amount of enzyme activity produced: pdash = short lag, high activity; pdasm = short lag, moderate activity; and pdall = long lag, low activi ...19989683653
characterization and nitrogen-source regulation at the transcriptional level of the gdha gene of aspergillus awamori encoding an nadp-dependent glutamate dehydrogenase.a 28.7-kb dna region containing the gdha gene of aspergillus awamori was cloned from a genomic dna library. a fragment of 2570 nucleotides was sequenced that contained orf1, of 1380 bp, encoding a protein of 460 amino acids (mr 49.4 kda). the encoded protein showed high similarity to the nadp-dependent glutamate dehydrogenases of different organisms. the cloned gene was functional since it complemented two different aspergillus nidulans gdha mutants, restoring high levels of nadp-dependent gluta ...19989683675
structure of dehydroquinate synthase reveals an active site capable of multistep catalysis.dehydroquinate synthase (dhqs) has long been regarded as a catalytic marvel because of its ability to perform several consecutive chemical reactions in one active site. there has been considerable debate as to whether dhqs is actively involved in all these steps, or whether several steps occur spontaneously, making dhqs a spectator in its own mechanism. dhqs performs the second step in the shikimate pathway, which is required for the synthesis of aromatic compounds in bacteria, microbial eukaryo ...19989685163
in situ detection of protein-dna interactions in filamentous fungi by in vivo footprinting.the method described here allows the detection of protein-dna interactions in vivo in filamentous fungi. we outline culture conditions and conditions of in vivo methylation that permit uniform modification of all cells in an apically growing, non-uniform organism, and subsequent visualization of protected areas by ligation-mediated pcr.19989685506
genotoxicity of an extract of calendula officinalis l.a fluid extract of calendula officinalis l. displayed genotoxic properties when assayed for mitotic segregation in the heterozygous diploid d-30 of aspergillus nidulans. the extract of calendula exhibited dose-dependent toxicity and genotoxicity (both mitotic crossing-over and chromosome malsegregation being observed) to aspergillus in the range of five plate concentrations from 0.1 to 1.0 mg of solids/ml assayed. mutagenicity testing with the salmonella/microsome assay in strains ta 1535, ta 15 ...19989687081
analysis of flug mutations that affect light-dependent conidiation in aspergillus nidulans.conidiation in aspergillus nidulans is induced by exposure to red light but can also be induced by blue light in certain mutant strains. we have isolated a mutation in the flug gene that abolishes responsiveness to red light but does not affect the response to blue light. it has been shown that the vea1 (velvet) mutation allows conidiation to occur in the absence of light. we have identified three other flug mutations that suppress the vea1 phenotype; these double mutants do not conidiate in the ...19989691036
molecular cloning and cell-cycle-dependent expression of a novel nima (never-in-mitosis in aspergillus nidulans)-related protein kinase (tpnrk) in tetrahymena cells.with the intention of investigating the signal-transduction pathway that mediates the cold-stress response in tetrahymena, we isolated a gene that encodes a novel protein kinase of 561 amino acids, termed tetrahymena pyriformis nima (never-in-mitosis in aspergillus nidulans)-related protein kinase (tpnrk), by differential display from tetrahymena cells exposed to temperature shift-down. tpnrk possesses an n-terminal protein kinase domain that is highly homologous with other nima-related protein ...19989693120
isolation of mutants deficient in acetyl-coa synthetase and a possible regulator of acetate induction in aspergillus niger.acetate-non-utilizing mutants in aspergillus niger were selected by resistance to 1.2% propionate in the presence of 0.1% glucose. mutants showing normal morphology fell into two complementation groups. one class of mutant lacked acetyl-coa synthetase but had high levels of isocitrate lyase, while the second class showed reduced levels of both acetyl-coa synthetase and isocitrate lyase compared to the wild-type strain. by analogy with mutants selected by resistance to 1.2% propionate in aspergil ...19989695922
catalytic activity in cephalosporium acremonium isopenicillin n synthase does not involve glutamine-234.the catalytic activity of isopenicillin n synthase (ipns), a crucial enzyme which converts delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine to isopenicillin n in the beta-lactam antibiotic biosynthetic pathway, is known to be dependent upon the ligation of two histidines and an aspartate to the iron active centre. recent studies have ruled out the suggested requirement of the penultimate glutamine, q330 and q328 in aspergillus nidulans and streptomyces jumonjinensis ipns respectively, for cataly ...19989703965
regulation of gmnrt2 expression and nitrate transport activity in roots of soybean (glycine max).a full-length cdna, gmnrt2, encoding a putative high-affinity nitrate transporter was isolated from a glycine max (l.) root cdna library and sequenced. the deduced gmnrt2 protein is 530 amino acids in length and contains 12 putative membrane-spanning domains and a long, hydrophilic c-terminal domain. gmnrt2 is related to high-affinity nitrate transporters in the eukaryotes chlamydomonas reinhardtii and aspergillus nidulans, and to putative high-affinity nitrate transporters in barley and tobacco ...19989715532
correlation between the regulation of sterigmatocystin biosynthesis and asexual and sexual sporulation in emericella nidulans.we analyzed the regulation of sterigmatocystin biosynthesis in wild type and mutant strains of emericella nidulans (= aspergillus nidulans). a positive correlation between both asexual and sexual sporulation and synthesis of the mycotoxin was observed. those conditions which favored sporulation stimulated sterigmatocystin formation, and vice versa. both processes were stimulated by light in a vea+ genetic background. in contrast, they were inhibited by diaminobutanone, an inhibitor of ornithine ...19989717578
role of endoproteolytic dibasic proprotein processing in maturation of secretory proteins in trichoderma reesei.cell extracts of trichoderma reesei exhibited dibasic endopeptidase activity toward the carboxylic side of kr, rr, and pr sequences. this activity was stimulated by the presence of ca2+ ions and localized in vesicles of low bouyant density; it therefore exhibited some similarity to yeast kex2. analytical chromatofocusing revealed a single peak of activity. the dibasic endopeptidase activity was strongly and irreversibly inhibited in vitro as well as in vivo by 1 mm p-amidinophenylmethylsulfonyl ...19989726860
role of the regulatory gene area of aspergillus oryzae in nitrogen metabolism.the area gene of aspergillus oryzae was cloned by cross-hybridization with the aspergillus nidulans area gene and was found to encode an 866-amino-acid protein that is very similar to other fungal nitrogen regulatory proteins. the a. oryzae area gene can complement a. nidulans area loss-of-function mutations. functional analyses indicated that the n-terminal region of the a. oryzae area protein was dispensable for function and revealed a probable acidic activation domain in the protein. c-termin ...19989726865
molecular regulation of beta-lactam biosynthesis in filamentous fungi.the most commonly used beta-lactam antibiotics for the therapy of infectious diseases are penicillin and cephalosporin. penicillin is produced as an end product by some fungi, most notably by aspergillus (emericella) nidulans and penicillium chrysogenum. cephalosporins are synthesized by both bacteria and fungi, e.g., by the fungus acremonium chrysogenum (cephalosporium acremonium). the biosynthetic pathways leading to both secondary metabolites start from the same three amino acid precursors an ...19989729600
mutational analysis of area, a transcriptional activator mediating nitrogen metabolite repression in aspergillus nidulans and a member of the "streetwise" gata family of transcription factors.the transcriptional activator area is a member of the gata family of transcription factors and mediates nitrogen metabolite repression in the fungus aspergillus nidulans. the nutritional versatility of a. nidulans and its amenability to classical and reverse genetic manipulations make the area dna binding domain (dbd) a useful model for analyzing gata family dbds, particularly as structures of two area-dna complexes have been determined. the 109 extant mutant forms of the area dbd surveyed here ...19989729601
molecular probes for the detection of pathogenic fungi in the presence of human tissue.four primer systems, amplifying fragments of the gene coding for the small ribosomal subunit (18s rrna) were characterised with pure cultures of 65 medically relevant fungal species plus two mushrooms. a primer cocktail (tr1/ca1-tr2/af2) amplified 59 of 67 fungal species; the universal fungal primer 1 (uf1) in combination with the eukaryotic primers s3 or eu1 amplified 64 and 65 of 67 fungal species, respectively. the design of an additional primer (rzy1) enabled the amplification of the missing ...19989736163
the uvsc and uvse genes of aspergillus nidulans are not required for the mutagenic repair of uv damage.the uvsc gene of aspergillus nidulans is a homolog of the rad51 gene of saccharomyces cerevisiae. however, with respect to its effects on uv mutagenesis, it differs from the yeast gene, since it seems to be required for uv mutagenesis; however, this conclusion is based only on data from resting conidia. to further clarify the functional role of the uvsc gene, we tested the uv mutability of strains bearing a uvsc mutation in resting as well as in germinating conidia, by the p-fluorophenyl-alanine ...19989738889
mitosis in wild-type and beta-tubulin mutant strains of aspergillus nidulans.we review and illustrate the wild-type mitotic cycle of aspergillus nidulans and report the sequence alterations in six mutant alleles of the a. nidulans bena, beta-tubulin, gene. these alleles confer heat sensitivity and resistance to the antifungal, antimicrotubule compound benomyl, and they have been very important in the study of mitosis and microtubule function in a. nidulans. the mutations are novel and fall at amino acids 50, 134, and 257. we have examined the phenotypes conferred by the ...19989742199
in vivo addition of telomeric repeats to foreign dna generates extrachromosomal dnas in the taxol-producing fungus pestalotiopsis microspora.transformation of the taxol-producing filamentous fungus pestalotiopsis microspora with a plasmid containing the bacterial hygromycin resistance gene fused to aspergillus regulatory sequences resulted in the in vivo formation of extrachromosomal dnas with telomeric repeats in the majority of transformants. repeats of the telomeric sequence 5'-ttaggg-3' were appended to nontelomeric transforming dna termini. no fungal sequences other than telomeric repeats were detected in extrachromosomal dnas. ...19989756714
in vitro activity of the echinocandin antifungal agent ly303,366 in comparison with itraconazole and amphotericin b against aspergillus spp.ly303,366 (ly) is a novel derivative of the echinocandin class of antifungal agents. the in vitro activities of ly, itraconazole (itz), and amphotericin b (amb) were assessed against 60 aspergillus isolates, including 35 isolates of a. fumigatus, eight isolates of a. terreus, eight isolates of a. flavus, eight isolates of a. niger and one isolate of a. nidulans. four a. fumigatus isolates were resistant to itz. susceptibility testing for all drugs was performed with a broth microdilution procedu ...19989756785
structural requirements for in vivo myosin i function in aspergillus nidulans.we have investigated the minimal requirements of the tail region for myosin i function in vivo using the filamentous fungus aspergillus nidulans. the cl3 strain (mcgoldrick, c. a., gruver, c., and may, g. s. (1995) j. cell biol. 128, 577-587) was transformed with a variety of myoa constructs containing mutations in the iq, th-1-like, sh3, and proline-rich domains by frameshift or in-frame deletions of the tail domains. the resulting strains contained wild type myoa driven by the alca promoter an ...19989756952
the area(r) mutation of aspergillus nidulans confers low ph sensitivity in the presence of ammonium as the only nitrogen source.the utilization of nitrogen sources by the fungus aspergillus nidulans is controlled by a mechanism mediated by area, a wide domain regulatory gene. it has been verified that the strains carrying the mutant allele arear are inhibited when growing at low ph in the presence of ammonium as the only nitrogen source. the genetic analysis of this marker showed that it apparently maps at the area locus.19989758458
regulation of aflr and its product, aflr, associated with aflatoxin biosynthesis.we studied the role of the regulatory gene aflr and its product, aflr, in the biosynthesis of aflatoxin in aspergillus. western blot and enzyme-linked immunosorbent assay analyses revealed that aflatoxin b1 accumulation was directly related to aflr expression and was regulated by various environmental and nutritional conditions, including temperature, air supply, carbon source, nitrogen source, and zinc availability. expression of an aflatoxin biosynthetic pathway structural gene, omta, was regu ...19989758790
a novel atp-binding cassette transporter involved in multidrug resistance in the phytopathogenic fungus penicillium digitatum.demethylation inhibitor (dmi)-resistant strains of the plant pathogenic fungus penicillium digitatum were shown to be simultaneously resistant to cycloheximide, 4-nitroquinoline-n-oxide (4nqo), and acriflavine. a pmr1 (penicillium multidrug resistance) gene encoding an atp-binding cassette (abc) transporter (p-glycoprotein) was cloned from a genomic dna library of a dmi-resistant strain (lc2) of penicillium digitatum by heterologous hybridization with a dna fragment containing an abc-encoding re ...19989758830
successful treatment of invasive aspergillosis in chronic granulomatous disease by bone marrow transplantation, granulocyte colony-stimulating factor-mobilized granulocytes, and liposomal amphotericin-b.x-linked chronic granulomatous disease (x-cgd) is a primary immunodeficiency with complete absence or malfunction of the nicotinamide adenine dinucleotide phosphate (nadph) oxidase in the phagocytic cells. life-threatening infections especially with aspergillus are common despite optimal antimicrobial therapy. bone marrow transplantation (bmt) is contraindicated during invasive aspergillosis in any disease setting. we report an 8-year-old patient with cgd who underwent hla-genoidentical bmt duri ...19989763555
aspergillus nidulans infection in chronic granulomatous disease.chronic granulomatous disease (cgd) is a rare inherited disorder of the nadph oxidase complex in which phagocytes are defective in generating reactive oxidants. as a result, patients with cgd suffer from recurrent bacterial and fungal infections. the most common fungal infections are caused by aspergillus species. aspergillus nidulans is a rare pathogen in most patient populations with quantitative or qualitative neutrophil defects. we have reviewed all cases in which a. nidulans was isolated fr ...19989772923
sequencing of a gene encoding a member of the mitochondrial carrier family of transport proteins from aspergillus nidulans.mitochondrial carrier proteins comprise a superfamily of evolutionarily conserved proteins that regulate the specific transport of essential metabolites across the mitochondrial membranes. in this report we describe the cloning and sequencing of a gene from aspergillus nidulans, amc-1, that encodes the first reported example of a mitochondrial carrier protein in aspergillus species. the amc-1 gene is located on chromosome 7, and is transcribed as a 1.6 kb unspliced polyadenylated rna. the predic ...19989773270
characterization of an aspergillus nidulans mutant with abnormal distribution of nuclei in hyphae, metulae, phialides and conidia.the v10 deteriorated variant of aspergillus nidulans has hyphae, metulae, phialides and conidia with abnormal nuclear distributions. the alterations observed were: increase in the number of nuclei in hyphae, metulae and phialides, presence of anucleate, uninucleate and multinucleate conidia, abnormal vegetative growth and defection conidiation. when 0.5 m nacl was added to the medium, an increase in the number of conidia was observed but their morphology and number of nuclei were not modified. t ...19989776635
polar lipids of aspergillus fumigatus, a. niger, a. nidulans, a. flavus and a. terreus.little is known of the phospholipid composition of aspergillus species. the aim of this study was to determine individual phospholipid analogues in aspergillus. twenty-nine clinical and environmental isolates from five aspergillus species were analysed. fast atom bombardment mass spectrometric data were considered in two ranges, m/z 190-500 and m/z 500-1000, to facilitate the recognition of major fatty acyl groups and phospholipids. quantitative comparison of major anions in both m/z ranges was ...19989776825
the identification and phylogenetic relationship of pathogenic species of aspergillus based on the mitochondrial cytochrome b study the identification and phylogeny of pathogenic isolates of aspergillus, we designed primers from known cytochrome b amino acid sequences. using these primers, 426 bp fragments of a mitochondrial (mt) cytochrome b gene were amplified by polymerase chain reaction (pcr), directly sequenced, and compared among aspergillus fumigatus, a. flavus, a. niger, a. terreus and emericella nidulans. except for e. nidulans, all strains produced the 426 bp fragment by pcr. the e. nidulans strains demons ...19989776828
immunological characterization of asp f 2, a major allergen from aspergillus fumigatus associated with allergic bronchopulmonary aspergillosis.the 37-kda recombinant protein asp f 2, encoding an allergen of aspergillus fumigatus, was expressed in a prokaryotic expression system and immunologically evaluated for its functional and structural properties. the open reading frame for a 310-amino-acid-long protein was shown to encode a signal peptide of 31 amino acids. a native 37-kda culture filtrate protein and a 55-kda mycelial glycoprotein (gp55) exhibited complete n-terminal sequence homology to asp f 2. a genbank search for homologous ...19989784519
posttranscriptional control mediates cell type-specific localization of catalase a during aspergillus nidulans development.two differentially regulated catalase genes have been identified in the fungus aspergillus nidulans. the cata gene belongs to a class whose transcripts are specifically induced during asexual sporulation (conidiation) and encodes a catalase accumulated in conidia. using a developmental mutant affected in the brla gene, which is unable to form conidia but capable of producing sexual spores (ascospores), we demonstrated that the cata mrna accumulated during induction of conidiation but did not pro ...19989791126
deletion of the 389 n-terminal residues of the transcriptional activator area does not result in nitrogen metabolite derepression in aspergillus nidulans.utilizing a homologous gene replacement in order to retain the native promoter and 5' and 3' untranslated messenger regions (and thereby ensure physiological validity), we have shown that deletion of the n-terminal 389 amino acids of the transcriptional activator area does not result in nitrogen metabolite derepression in aspergillus nidulans. our results provide no evidence for a modulating interaction involving the n terminus of area and contrast with those of h. k. lamb, a. l. dodds, d. r. sw ...19989791130
putative membrane components of signal transduction pathways for ambient ph regulation in aspergillus and meiosis in saccharomyces are homologous.the zinc finger regions of the aspergillus nidulans pacc transcription factor, mediating regulation of gene expression by ambient ph, and the saccharomyces cerevisiae rim1p transcription factor, mediating control of meiosis and invasiveness, are homologous and both transcription factors undergo proteolytic processing of the c-terminus for conversion to the functional form. in both cases, functioning of a signal transduction pathway involving several gene products is a necessary prerequisite for ...19989791171
regulation of the anaphase-promoting complex/cyclosome by bimaapc3 and proteolysis of nima.surprisingly, although highly temperature-sensitive, the bima1(apc3) anaphase-promoting complex/cyclosome (apc/c) mutation does not cause arrest of mitotic exit. instead, rapid inactivation of bima1(apc3) is shown to promote repeating oscillations of chromosome condensation and decondensation, activation and inactivation of nima and p34(cdc2) kinases, and accumulation and degradation of nima, which all coordinately cycle multiple times without causing nuclear division. these bima1(apc3)-induced ...19989802893
characterization of aspergillus nidulans peroxisomes by immunoelectron previous work, we have demonstrated that oleate induces a massive proliferation of microbodies (peroxisomes) in aspergillus nidulans. although at a lower level, proliferation of peroxisomes also occurs in cells growing under conditions that induce penicillin biosynthesis. here, microbodies in oleate-grown a. nidulans cells were characterized by using several antibodies that recognize peroxisomal enzymes and peroxins in a broad spectrum of eukaryotic organisms such as yeast, and plant, and mam ...19989818356
analysis of glutamines in catalysis in cephalosporium acremonium isopenicillin n synthase by site-directed mutagenesis.isopenicillin n synthase (ipns), an important enzyme in the beta-lactam antibiotic biosynthetic pathway, is responsible for the catalytic conversion of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine to isopenicillin n. three catalytic ligands essential for ipns activity have already been determined. based on an aspergillus nidulans ipns crystal structure, the probable involvement of a fourth amino acid as a catalytic ligand was previously revealed. to continue the search for the fourth catalyt ...19989826554
isolation and characterization of alpha-tubulin genes from septoria tritici and rhynchosporium secalis, and comparative analysis of fungal alpha-tubulin sequences.the alpha-tubulin genes from septoria tritici and rhynchosporium secalis have been cloned and sequenced. the predicted amino acid sequence and intron structure showed strong homology with other known filamentous fungal alpha-tubulins. comparison of sixteen fungal alpha-tubulin sequences based on amino acid sequence homology and intron structure identified five groups of proteins. group 1 consists of filamentous fungi, including s. tritici and r. secalis, the dimorphic fungus histoplasma capsulat ...19989829778
the facc gene of aspergillus nidulans encodes an acetate-inducible carnitine acetyltransferase.mutations in the facc gene of aspergillus nidulans result in an inability to use acetate as a sole carbon source. this gene has been cloned by complementation. the proposed translation product of the facc gene has significant similarity to carnitine acetyltransferases (cat) from other organisms. total cat activity was found to be inducible by acetate and fatty acids and repressed by glucose. acetate-inducible activity was found to be absent in facc mutants, while fatty acid-inducible activity wa ...19989829933
the optimization of penicillin biosynthesis in fungi.penicillin production by penicillium chrysogenum is not only commercially important but arguably the most intensively investigated secondary-metabolic pathway in fungi. isolation of the structural genes encoding the three main penicillin-biosynthetic enzymes has stimulated the use of molecular approaches to optimize yield and permitted genetic analysis of current production strains, which are themselves the products of 50 years of strain and process improvement. parallel studies on the penicilli ...19989830157
identification of a polyketide synthase gene (pksp) of aspergillus fumigatus involved in conidial pigment biosynthesis and virulence.aspergillus fumigatus is an important pathogen of the immunocompromised host causing pneumonia and invasive disseminated disease with high mortality. previously, we identified a mutant strain (white, w) lacking conidial pigmentation and, in addition, the conidia showed a smooth surface morphology, whereas wild-type (wt) conidia are grey-green and have a typical ornamentation. w conidia appeared to be less protected against killing by the host defence, e.g., were more susceptible to oxidants in v ...19989832321
the "8-kd" cytoplasmic dynein light chain is required for nuclear migration and for dynein heavy chain localization in aspergillus nidulans.the heavy chain of cytoplasmic dynein is required for nuclear migration in aspergillus nidulans and other fungi. here we report on a new gene required for nuclear migration, nudg, which encodes a homologue of the "8-kd" cytoplasmic dynein light chain (cdlc). we demonstrate that the temperature sensitive nudg8 mutation inhibits nuclear migration and growth at restrictive temperature. this mutation also inhibits asexual and sexual sporulation, decreases the intracellular concentration of the nudg ...19989832552
mutational evidence for the role of serine-283 in cephalosporium acremonium isopenicillin n synthase.creation of isopenicillin n from delta-(l-alpha-aminodipyl)-l-cysteinyl-d-valine (acv) in the penicillin and cephalosporin biosynthetic pathway is catalysed by isopenicillin n synthase (ipns), a non-heme iron-containing dioxygenase. a tripeptide r-x-s motif which consists of arginine-281 and serine-283 (cephalosporium acremonium ipns numbering) was found to be conserved in ipns and other related proteins. these two amino acids mentioned were proposed to have a role in acv substrate binding by th ...19989841222
cloning and biochemical characterisation of aspergillus niger hexokinase--the enzyme is strongly inhibited by physiological concentrations of trehalose 6-phosphate.the aspergillus niger hexokinase gene hxka has been cloned by heterologous hybridisation using the aspergillus nidulans hexokinase gene as a probe. the dna sequence of the gene was determined, and the deduced amino acid sequence showed significant similarity to other eukaryotic hexokinase and glucokinase proteins, in particular to those of the budding yeasts. the encoded protein was purified from a multicopy hxka transformant, and extensively characterised. the hexokinase protein has a molecular ...19989851713
two adjacent protein binding motifs in the cbh2 (cellobiohydrolase ii-encoding) promoter of the fungus hypocrea jecorina (trichoderma reesei) cooperate in the induction by cellulose.the cellulase system of the filamentous fungus hypocrea jecorina (trichoderma reesei) consists of several cellobiohydrolases, endoglucanases, and beta-glucosidases, encoded by separate genes, which are coordinately expressed in the presence of cellulose or the disaccharide sophorose. using cell-free extracts from sophorose-induced and noninduced mycelia and various fragments of the cbh2 promoter of h. jecorina in electrophoretic mobility shift assay (emsa) analysis and performing in vitro and in ...19989852114
isolation of a nitrogen response regulator gene (nrr1) from metarhizium anisopliae.attempts to improve the effectiveness of entomopathogenic fungi as biological control agents require a clear understanding of the pathogenicity determinants at both the biochemical and molecular level. proteases play a key role in entomopathogenicity, allowing the fungus to penetrate the insect cuticle and rapidly invade the host. the most extensively studied of these protease activities, pr1a and pr2, are both subject to nitrogen derepression. the metarhizium anisopliae nrr1 (nitrogen response ...19989852945
ancf, the ccaat binding complex of aspergillus nidulans, contains products of the hapb, hapc, and hape genes and is required for activation by the pathway-specific regulatory gene amdr.ccaat binding factors (cbfs) positively regulating the expression of the amds gene (encoding acetamidase) and two penicillin biosynthesis genes (ipna and aata) have been previously found in aspergillus nidulans. the factors were called ancf and penr1, respectively. deletion of the hapc gene, encoding a protein with significant similarity to hap3p of saccharomyces cerevisiae, eliminated both ancf and penr1 binding activities. we now report the isolation of the genes hapb and hape, which encode pr ...19999858535
cloning of a thermostable ascorbate oxidase gene from acremonium sp. hi-25 and modification of the azide sensitivity of the enzyme by site-directed mutagenesis.a gene encoding a thermostable ascorbate oxidase (asom) was cloned from acremonium sp. hi-25 and sequenced. the gene comprised 1709 bp and was interrupted by a single intron of 57 bp. asom consisted of 551 amino acids including a signal peptide with a molecular mass of 61200, and contained four histidine-rich regions with high sequence homology to the corresponding regions of other multicopper oxidases. the asom gene was expressed in aspergillus nidulans under the aspergillus oryzae taka-amylase ...19989858779
nuclear migration, nucleokinesis and lissencephaly.during the past 20 years, biologists have become used to finding that proteins first identified in simple, genetically manipulable eukaryotic organisms are conserved in higher eukaryotes. this article draws attention to the similarity between nudf protein, which is required for nuclear migration in the filamentous fungus aspergillus nidulans, and a mammalian homologue, lis1, whose malfunction causes lissencephaly, a neuronal migration disease. the authors suggest that there might be an underlyin ...19989861667
in vivo linearization and autonomous replication of plasmids containing human telomeric dna in aspergillus nidulans.plasmids containing two inverted 0.6-kb stretches of human telomeric repeats transform aspergillus nidulans at frequencies characteristic of autonomously replicating vectors. transformation frequency is not affected when the plasmids are linearized in vitro prior to transformation by cutting between the inverted repeats. southern analysis reveals the presence of a homogeneous pool of linear plasmid molecules in mycelium of transformants. addition of the ama1 plasmid replicator to the telomere-co ...19989862467
repression of the expression of genes encoding xylanolytic enzymes in aspergillus oryzae by introduction of multiple copies of the xynf1 promoter.a xylanase gene, xynf1, was cloned and characterized from a shoyu koji mould aspergillus oryzae kbn616. the xynf1 gene was found to be comprised of 1484 bp with ten introns. the deduced amino acid sequence encodes a protein consisting of 327 amino acids (35,402 da) which is very similar to the fungal family f xylanases such as aspergillus nidulans xlnc, aspergillus kawachii xyna and penicillium chrysogenum xylp. the intron/exon organization of xynf1 is very similar to that of the fungal family f ...19989866173
isolation and characterisation of the acetyl-coa carboxylase gene from aspergillus nidulans.the putative gene encoding acetyl-coa carboxylase, acca, has been isolated from aspergillus nidulans. this single-copy gene has an open reading frame (orf) of 6864 bp and contains two small introns near the 5'-end. a short orf upstream of the atg start codon has been identified in this gene by rt-pcr. based on sequence homology to acetyl-coa carboxylases from other organisms, putative biotin-, atp-, hco3-- and acetyl-coa- binding sites have been assigned. northern data and acc enzyme-activity me ...19989871120
the use of cryopreserved apical protoplasts from curvularia lunata for electroporation method, utilizing cryopreserved protoplasts, has been developed for the steroid 11-hydroxylating fungus curvularia lunata strain im 2901. protoplasts released from the apical parts of 24- and 48-h-old mycelia were suspended in cryopreservation buffer and stored at -75 degrees c for several weeks. the thawed and freshly prepared (control) protoplasts were electroporated with pan 7-1 plasmid carrying the escherichia coli hygromycin b resistance gene (hph) under the control of as ...19989871997
sequence analysis, overexpression, and antisense inhibition of a beta-xylosidase gene, xyla, from aspergillus oryzae kbn616.beta-xylosidase secreted by the shoyu koji mold, aspergillus oryzae, is the key enzyme responsible for browning of soy sauce. to investigate the role of beta-xylosidase in the brown color formation, a major beta-xylosidase, xyla, and its encoding gene were characterized. beta-xylosidase xyla was purified to homogeneity from culture filtrates of a. oryzae kbn616. the optimum ph and temperature of the enzyme were found to be 4.0 and 60 degrees c, respectively, and the molecular mass was estimated ...19999872754
extragenic suppressors of loss-of-function mutations in the aspergillus flba regulator of g-protein signaling domain protein.we showed previously that two genes, fl ba and fada, have a major role in determining the balance between growth, sporulation, and mycotoxin (sterigmatocystin; st) production by the filamentous fungus aspergillus nidulans. fada encodes the alpha subunit for a heterotrimeric g-protein, and continuous activation of fada blocks sporulation and st production while stimulating growth. fl ba encodes an a. nidulans regulator of g-protein signaling (rgs) domain protein that antagonizes fada-mediated sig ...19999872951
basal body duplication in paramecium requires gamma-tubulin.first discovered in the fungus aspergillus nidulans[1], gamma-tubulin is a ubiquitous component of microtubule organizing centres [2]. in centrosomes, gamma-tubulin has been immunolocalized at the pericentriolar material, suggesting a role in cytoplasmic microtubule nucleation [3], as well as within the centriole core itself [4]. although its function in the nucleation of the mitotic spindle and of cytoplasmic interphasic microtubules has been demonstrated in vitro [5] [6] and in vivo[7] [8] [9] ...19999889124
the two subunits of human molybdopterin synthase: evidence for a bicistronic messenger rna with overlapping reading frames.molybdoenzymes are ubiquitous and require a prosthetic group called the molybdenum cofactor for activity. we provide evidence here that the two heteromeric subunits (moco1-a and moco1-b) of human molybdopterin synthase, which is involved in the conversion of precursor z to molybdopterin in the molybdenum cofactor biosynthetic pathway, are spe-cified by a single bicistronic mrna with overlapping reading frames. the transcript is in low abundance and shows variable tissue distribution. we propose ...19999889283
cloning and characterization of a eukaryotic pantothenate kinase gene (pank) from aspergillus nidulans.pantothenate kinase (pank) is the key regulatory enzyme in the coa biosynthetic pathway. the pank gene from escherichia coli (coaa) has been previously cloned and the enzyme biochemically characterized; highly related genes exist in other prokaryotes. we isolated a pank cdna clone from the eukaryotic fungus aspergillus nidulans by functional complementation of a temperature-sensitive e. coli pank mutant. the cdna clone allowed the isolation of the genomic clone and the characterization of the a. ...19999890959
specificity determinants of proteolytic processing of aspergillus pacc transcription factor are remote from the processing site, and processing occurs in yeast if ph signalling is bypassed.the aspergillus nidulans transcription factor pacc, which mediates ph regulation, is proteolytically processed to a functional form in response to ambient alkaline ph. the full-length pacc form is unstable in the presence of an operational ph signal transduction pathway, due to processing to the relatively stable short functional form. we have characterized and used an extensive collection of pacc mutations, including a novel class of "neutrality-mimicking" pacc mutations having aspects of both ...19999891072
methods for isolating and analyzing mitotic mutants in aspergillus nidulans. 19999891323
a novel 17beta-hydroxysteroid dehydrogenase in the fungus cochliobolus lunatus: new insights into the evolution of steroid-hormone signalling.17beta-hydroxysteroid dehydrogenase (17beta-hsd) from the filamentous fungus cochliobolus lunatus (17beta-hsdcl) catalyses the reduction of steroids and of several o- and p-quinones. after purification of the enzyme, its partial amino acid sequence was determined. a pcr fragment amplified with primers derived from peptide sequences was generated for screening the coch. lunatus cdna library. three independent full-length cdna clones were isolated and sequenced, revealing an 810-bp open reading fr ...19999895285
intra- and interspecies virus transfer in aspergilli via protoplast fusion.intra- and interspecies transfer of dsrna viruses between black aspergilli and aspergillus nidulans strains has been investigated using protoplast fusion. we found interspecies transfer of virus in all combinations of black aspergillus and a. nidulans strains and vice versa. using the same conditions, intraspecies virus transfer among heterokaryon incompatible strains was also tested. whereas such transfer was always found among a. nidulans strains, transfer among black aspergilli was frequently ...19989917371
isolation of csm1 encoding a class v chitin synthase with a myosin motor-like domain from the rice blast fungus, pyricularia oryzae.a gene encoding a chitin synthase with a myosin motor-like domain (csm1) was isolated from pyricularia oryzae using a pcr fragment amplified from a fungal chitin synthase conserved region. the deduced amino acid sequence of csm1 is homologous to that of csma of aspergillus nidulans (65% identity). the putative gene product of csm1 is consisted of the myosin motor-like domain and a chitin synthase domain as in a. nidulans csma. the chitin synthase domain of its c-terminus was also homologous to a ...19999919661
biophysical characterization of fungal phytases (myo-inositol hexakisphosphate phosphohydrolases): molecular size, glycosylation pattern, and engineering of proteolytic resistance.phytases (myo-inositol hexakisphosphate phosphohydrolases) are found naturally in plants and microorganisms, particularly fungi. interest in these enzymes has been stimulated by the fact that phytase supplements increase the availability of phosphorus in pig and poultry feed and thereby reduce environmental pollution due to excess phosphate excretion in areas where there is intensive livestock production. the wild-type phytases from six different fungi, aspergillus niger, aspergillus terreus, as ...19999925554
biochemical characterization of fungal phytases (myo-inositol hexakisphosphate phosphohydrolases): catalytic properties.supplementation with phytase is an effective way to increase the availability of phosphorus in seed-based animal feed. the biochemical characteristics of an ideal phytase for this application are still largely unknown. to extend the biochemical characterization of wild-type phytases, the catalytic properties of a series of fungal phytases, as well as escherichia coli phytase, were determined. the specific activities of the fungal phytases at 37 degreesc ranged from 23 to 196 u. (mg of protein)-1 ...19999925555
aspergillus nidulans swo mutants show defects in polarity establishment, polarity maintenance and hyphal morphogenesis.when the spores of filamentous fungi break dormancy, they grow isotropically, adding cell wall material uniformly in every direction. later they switch to polarized growth, with new material added to the tip of an emerging germ tube. to identify genes involved in the synthesis and localization of cell wall material in filamentous fungi, we screened a collection of temperature-sensitive aspergillus nidulans mutants for swollen cells. we have isolated mutants representing eight genes involved in p ...19999927451
molecular characterization of hyma, an evolutionarily highly conserved and highly expressed protein of aspergillus nidulans.aspergillus nidulans reproduces asexually via uninucleate, haploid spores, which are produced on morphologically differentiated aerial structures, called conidiophores. these consist of four distinct cell types, a foot with a terminally swollen stalk, metulae, phialides and conidiospores. the molecular mechanisms underlying the morphological changes that occur during conidiophore development have been studied by mutant analysis. we have isolated the hym a mutant, in which conidiophore developmen ...19999928930
the protease activity of a calpain-like cysteine protease in saccharomyces cerevisiae is required for alkaline adaptation and sporulation.abstract saccharomyces cerevisiae has only one putative gene (designated cpl1) for a cysteine protease with a protease domain similar to that of calpain. this gene product shows significant sequence similarity to palbp, a fungal (emericella nidulans) calpain-like protease that is responsible for adaptation under alkaline conditions, both in the protease domain and the domain following the protease domain. cpl1 disruptant strains show impaired growth at alkaline ph, but no obvious growth defects ...19999928935
the aspergillus nidulans glta gene encoding glutamate synthase is required for ammonium assimilation in the absence of nadp-glutamate dehydrogenase.mutants of aspergillus nidulans lacking nadp-glutamate dehydrogenase activity grow more poorly than wild-type strains on ammonium as a sole nitrogen source. the leaky growth of these mutants is indicative of an alternative pathway of ammonium assimilation and glutamate biosynthesis. we have pcr-amplified a portion of the a. nidulans gene encoding glutamate synthase and used this sequence to inactivate the genomic copy. this gene, designated glta, was found to be dispensable for growth on ammoniu ...19999933358
isolation of the crea gene from the cellulolytic fungus humicola grisea and analysis of crea binding sites upstream from the cellulase genes.a carbon catabolite repressor gene, crea, was isolated from the cellulolytic fungus humicola grisea by using a portion of the trichoderma reesei cre1 gene as a probe. the deduced amino acid sequence predicts a zinc finger protein of 419 amino acids in length, and its zinc finger regions show high similarity with those of aspergillus creas, t. reesei cre1, and saccharomyces cerevisiae mig1. northern blot analysis showed that the h. grisea crea gene was highly transcribed when the mycelia were gro ...19989972263
hydrogen peroxide inhibits the growth of cyanobacteria.h2o2 at concentrations of 10(-5)-10(-4) m suppresses phototrophic growth of anacystis nidulans and anabaena variabilis in dialysis culture. the growth of the cyanobacteria resumed after a long adaptation period. in batch cultures, the growth of a. nidulans and a. variabilis was suppressed after one-time addition of 10(-2)and 10(-3)-10(-2) m h2o2, respectively. inducing intracellular h2o2 formation by adding methylviologen, vitamin k3, or phenazine methosulfate suppresses the growth of both cyano ...19999986912
carbon catabolite repression of the aspergillus nidulans xlna gene.expression of the aspergillus nidulans 22 kda endoxylanase gene, xlna, is controlled by at least three mechanisms: specific induction by xylan or xylose; carbon catabolite repression (ccr); and regulation by ambient ph. deletion analysis of xlna upstream sequences has identified two positively acting regions: one that mediates specific induction by xylose; and another that mediates the influence of ambient ph and contains two pacc consensus binding sites. the extreme derepressed mutation cread30 ...19999987120
the mitochondrial genome of mucor piriformis.dna was purified from the isolated mitochondria of a mucor piriformis wild-type strain (nrrl 26211). a circular restriction map of the mitochondrial dna was established on the basis of single and double digests with several restriction endonucleases. the average mitochondrial dna size calculated from these data was 33.53 kbp; this is in good agreement with the contour length size (33.62 kbp) of the open circular molecules detected by electron microscopy. heterologous hybridizations with cloned a ...19999987843
fate of transforming dna in pathogenic fungi.genetic engineering is an important tool in helping us to define the molecular basis of pathogenicity and is also useful in helping us to identify new therapeutic targets in pathogenic fungi. molecular genetic manipulation of micro-organisms requires the development of plasmid-mediated transformation systems that include: (i) infusion of exogenous dna into recipient cells, (ii) expression of genes present on the incoming dna, and (iii) stable maintenance and replication of the inserted dna leadi ...19989988490
the aspergillus nidulans gata factor srea is involved in regulation of siderophore biosynthesis and control of iron uptake.a gene encoding a new gata factor from aspergillus nidulans, srea, was isolated and characterized. srea displays homology to two fungal regulators of siderophore biosynthesis: about 30% overall identity to sre from neurospora crassa and about 50% identity to urbs1 from ustilago maydis over a stretch of 200 amino acid residues containing two gata-type zinc finger motifs and a cysteine-rich region. this putative dna binding domain, expressed as a fusion protein in escherichia coli, specifically bi ...19999988696
comparison of gene structures and enzymatic properties between two endoglucanases from humicola grisea.we have cloned two endoglucanase genes (egl3 and egl4) from a thermophilic fungus, humicola grisea. the coding region of the egl3 gene was interrupted by an intron of 56-bp, and the deduced amino acid sequence of the egl3 gene was 305 amino acids in length and showed 98.4% identity with humicola insolens egv. the coding region of the egl4 gene was also interrupted by an intron of 173-bp, which contains 34 ttc repeated sequence units, and the deduced amino acid sequence of the egl4 gene was 227 a ...19999990729
organisation of the mitochondrial genome of trichophyton rubrum iii. dna sequence analysis of the nadh dehydrogenase subunits 1, 2, 3, 4, 5 and the cytochrome b this paper, we present the nucleotide sequence of a 9761 nt-long segment of the mitochondrial genome of the dermatophyte trichophyton rubrum that bridges the gap between two previously published segments, making a unique contig that represents approximately 80% of the molecule. the location of all genes on the map is determined except for some trna genes expected to flank the lsu rrna gene not yet sequenced. starting from the 5' end of the present sequence, we recognized the nd5 and nd2 genes ...199910022946
expression of atrc - encoding a novel member of the atp binding cassette transporter family in aspergillus nidulans - is sensitive to cycloheximide.a new member of the abc superfamily of transmembrane proteins in aspergillus nidulans has been cloned and characterized. the topology of conserved motifs subgroups atrc in the p-glycoprotein cluster of abc permeases, the members of this subfamily, are known to participate in multidrug resistance (mdr) in diverse organisms. alignment results display significant amino acid similarity to afumdr1 and aflmdr1 from aspergillus fumigatus and flavus, respectively. northern analysis reveals that atrc mrn ...199910036328
demonstration of molecular interactions between the murein polymerase pbp1b, the lytic transglycosylase mlta, and the scaffolding protein mipa of escherichia coli.enlargement of the stress-bearing murein sacculus of bacteria depends on the coordinated interaction of murein synthases and hydrolases. to understand the mechanism of interaction of these two classes of proteins affinity chromatography and surface plasmon resonance (spr) studies were performed. the membrane-bound lytic transglycosylase mlta when covalently linked to cnbr-activated sepharose specifically retained the penicillin-binding proteins (pbps) 1b, 1c, 2, and 3 from a crude triton x-100 m ...199910037771
cytoplasmic dynein and dynactin in cell division and intracellular transport.since the initial discovery of cytoplasmic dynein, it has become apparent that this microtubule-based motor is involved in several cellular functions including cell division and intracellular transport. another multisubunit complex, dynactin, may be required for most, if not all, cytoplasmic dynein-driven activities and may provide clues to dynein's functional diversity. recent genetic and biochemical findings have illuminated the cellular roles of dynein and dynactin and provided insight into t ...199910047518
thaumatin production in aspergillus awamori by use of expression cassettes with strong fungal promoters and high gene dosage.four expression cassettes containing strong fungal promoters, a signal sequence for protein translocation, a kex protease cleavage site, and a synthetic gene (tha) encoding the sweet protein thaumatin ii were used to overexpress this protein in aspergillus awamori lpr66, a pepa protease-deficient strain. the best expression results were obtained with the gdha promoter of a. awamori or with the gpda promoter of aspergillus nidulans. there was good correlation of tha gene dosage, transcript levels ...199910049878
organization of the gene cluster for biosynthesis of penicillin in penicillium nalgiovense and antibiotic production in cured dry sausages.several fungal isolates obtained from two cured meat products from spain were identified as penicillium nalgiovense by their morphological features and by dna fingerprinting. all p. nalgiovense isolates showed antibiotic activity in agar diffusion assays, and their penicillin production in liquid complex medium ranged from 6 to 38 microgram. ml-1. we constructed a restriction map of the penicillin gene cluster of p. nalgiovense and found that the organization of the penicillin biosynthetic genes ...199910049889
identification and characterization of genes required for hyphal morphogenesis in the filamentous fungus aspergillus the filamentous fungus aspergillus nidulans, germination of an asexual conidiospore results in the formation of a hyphal cell. a key feature of spore germination is the switch from isotropic spore expansion to polarized apical growth. here, temperature-sensitive mutations are used to characterize the roles of five genes (sepa, hypa, podb-podd) in the establishment and maintenance of hyphal polarity. evidence that suggests that the hypa, podb, and sepa genes are required for multiple aspects o ...199910049919
insertion analysis of putative functional elements in the promoter region of the aspergillus oryzae taka-amylase a gene (amyb) using a heterologous aspergillus nidulans amds-lacz fusion gene system.expression of the taka-amylase a gene (amyb) of aspergillus oryzae is induced by starch or maltose. the a. oryzae amyb gene promoter contains three highly conserved sequences, designated regions i, ii, and iii, compared with promoter regions of the a. oryzae glaa encoding glucoamylase and the agda encoding alpha-glucosidase. to identify the function of these sequences within the amyb promoter, various fragments containing conserved sequences in the amyb promoter were introduced into the upstream ...199910052139
depression of the xylanase-encoding cgxa gene of chaetomium gracile in aspergillus nidulans.regulation of the chaetomium gracile xylanase a gene (cgxa) was investigated using aspergillus nidulans as an intermediate host. deletion of a 185 bp dna fragment from its promoter region led to higher levels of the cgxa gene expression, indicating that the 185 bp dna fragment contains an element involved in repression of the gene. a nuclear extract was assayed for proteins which bind to the 185 bp dna fragment. a protein designated anrp bound sequence specifically to the dna fragment. the minim ...199910052158
coordinate control of secondary metabolite production and asexual sporulation in aspergillus nidulans.microbial secondary metabolite production is frequently associated with developmental processes such as sporulation, but there are few cases where this correlation is understood. recent work with the filamentous fungus aspergillus nidulans has provided new insights into the mechanisms coordinating production of the toxic secondary metabolite sterigmatocystin with asexual sporulation. these processes have been shown to be linked through a common need to inactivate a heterotrimeric g protein depen ...199810066549
isolation, characterization and disruption of the area nitrogen regulatory gene of gibberella fujikuroi.the gene area-gf, a homologue of the major nitrogen regulatory genes nit-2, area, nre and nut1 of neurospora crassa, aspergillus nidulans, penicillium chrysogenum and magnaporthe grisea, respectively, was cloned from the gibberellin (ga)-producing rice pathogen gibberella fujikuroi. area-gf encodes a protein of 972 amino acid residues which contains a single putative zinc finger dna-binding domain that is at least 98% identical to the zinc finger domains of the homologous fungal proteins. the ar ...199910071216
rapid hypothesis testing with candida albicans through gene disruption with short homology regions.disruption of newly identified genes in the pathogen candida albicans is a vital step in determination of gene function. several gene disruption methods described previously employ long regions of homology flanking a selectable marker. here, we describe disruption of c. albicans genes with pcr products that have 50 to 60 bp of homology to a genomic sequence on each end of a selectable marker. we used the method to disrupt two known genes, arg5 and ade2, and two sequences newly identified through ...199910074081
the gata factor area is essential for chromatin remodelling in a eukaryotic bidirectional promoter.the linked niia and niad genes of aspergillus nidulans are transcribed divergently. the expression of these genes is subject to a dual control system. they are induced by nitrate and repressed by ammonium. area mediates derepression in the absence of ammonium and nira supposedly mediates nitrate induction. out of 10 gata sites, a central cluster (sites 5-8) is responsible for approximately 80% of the transcriptional activity of the promoter on both genes. we show occupancy in vivo of site 5 by t ...199910075929
aspergillus fumigatus catalases: cloning of an aspergillus nidulans catalase b homologue and evidence for at least three catalases.the presence of catalases in the water soluble fractions of three aspergillus fumigatus strains was investigated using non-denaturing and denaturing polyacrylamide gel electrophoresis and western analysis. using non-denaturing polyacrylamide gel electrophoresis and staining for catalase activity, three separate catalases were identified. an a. fumigatus catalase gene (catb) was cloned from genomic dna using the aspergillus niger catr gene as a probe. polyclonal antibodies were raised to a glutat ...199910076909
identification and linkage mapping of the phsa gene of aspergillus nidulans, where mutation affects growth and pigmentation of colonies in a temperature- and ph-dependent way.we report the isolation and characterization of a mutant strain of the mold aspergillus nidulans showing an altered response to environmental ph, including a reduction in its ph range for growth and the production of a melanin-like pigment at alkaline ph. we also show that the mutant strain is not detergent-sensitive and that its acid sensitivity is osmotically remediable with 0.5 m nacl or 1.0 m sorbitol. furthermore, the mutant phenotype is temperature-remediable with respect to pigmentation, ...199910077833
nuclear movement in filamentous of the most striking features of eukaryotic cells is the organization of specific functions into organelles such as nuclei, mitochondria, chloroplasts, the endoplasmic reticulum, vacuoles, peroxisomes or the golgi apparatus. these membrane-surrounded compartments are not synthesized de novo but are bequeathed to daughter cells during cell division. the successful transmittance of organelles to daughter cells requires the growth, division and separation of these compartments and involves a co ...199910077853
cloning, characterisation and regulation of the ornithine transaminase (otaa) gene of aspergillus nidulans.the ornithine transaminase (otaa) gene of aspergillus nidulans has been cloned by transformation of the a. nidulans pro-ota- mutant strain with a cosmid gene library. the otaa gene contains two introns and potentially codes for a 453-aa-long protein. the deduced amino-acid sequence is homologous to known ornithine transaminases from saccharomyces cerevisiae, plasmodium falciparum, vigna aconitifolia, rat, mouse and man, particularly in the pyridoxal phosphate-binding domain. the expression of th ...199910079330
the tama mutants of aspergillus nidulans. 199910079333
unique dna binding specificity of the binuclear zinc alcr activator of the ethanol utilization pathway in aspergillus nidulans.alcr is the transcriptional activator in aspergillus nidulans, necessary for the induction of the alc gene cluster. it belongs to the zn2cys6 zinc cluster protein family, but contains some striking differences compared with other proteins of this group. in this report, we show that no dimerization element is present in the entire alcr protein which occurs in solution as a monomer and binds also to its cognate sites as a monomer. another important feature of alcr is its unique specificity for sin ...199910092669
increased nuclear traffic chaos in hyphae of aspergillus nidulans: molecular characterization of apsb and in vivo observation of nuclear behaviour.filamentous fungi are model microorganisms for studying nuclear migration in eukaryotic cells. two genes, apsa and apsb (=anucleate primary sterigmata), were identified in aspergillus nidulans that affect nuclear distribution in hyphae and specifically block conidiophore development at the metula stage when mutant. here we describe the cloning, sequencing and molecular analysis of apsb. the gene encodes a 121 kda coiled-coil, hydrophilic protein that was localized in the cytoplasm. no protein-pr ...199810094631
the hxb gene, necessary for the post-translational activation of purine hydroxylases in aspergillus nidulans, is independently controlled by the purine utilization and the nicotinate utilization transcriptional activating systems.molybdenum-containing enzymes of the hydroxylase class (such as xanthine dehydrogenase, aldehyde oxidase and nicotinate dehydrogenase) require a terminal sulphur atom attached to the molybdenum to hydroxylate their specific substrates. the transulphurylation reaction is carried out in drosophila melanogaster by the product of the ma-i gene. in aspergillus nidulans, the activity of the isofunctional and homologous hxb protein is needed in at least two different metabolic contexts, when the organi ...199910096075
a single amino acid, outside the alcr zinc binuclear cluster, is involved in dna binding and in transcriptional regulation of the alc genes in aspergillus aspergillus nidulans, the transcriptional activator alcr mediates specific induction of a number of alc genes. the alcr dna-binding domain is a zinc binuclear cluster that differs from the other members of the zn2cys6 family in several respects. of these, the most remarkable is its ability to bind in vitro as a monomer to single sites, whereas only repeated sites (direct or inverted) are necessary and functional in vivo. deletion of the first five amino acids (following the n-terminal methion ...199910096079
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