| the rational design of semisynthetic peroxidases. | a semisynthetic peroxidase was designed by exploiting the structural similarity of the active sites of vanadium dependent haloperoxidases and acid phosphatases. incorporation of vanadate ion into the active site of phytase (e.c. 3.1.3.8), which mediates in vivo the hydrolysis of phosphate esters, leads to the formation of a semisynthetic peroxidase, which catalyzes the enantioselective oxidation of prochiral sulfides with h(2)o(2) affording the s-sulfoxide, e.g. in 66% ee at 100% conversion for ... | 2000 | 10581439 |
| proton-pumping-atpase-targeted antifungal activity of a novel conjugated styryl ketone. | nc1175 (3-[3-(4-chlorophenyl)-2-propenoyl]-4-[2-(4-chlorophenyl)vinyle ne]-1- ethyl-4-piperidinol hydrochloride) is a novel thiol-blocking conjugated styryl ketone that exhibits activity against a wide spectrum of pathogenic fungi. incubation of nc1175 with various concentrations of cysteine and glutathione eliminated its antifungal activity in a concentration-dependent fashion. since nc1175 is a lipophilic compound that has the potential to interact with cytoplasmic membrane components, we exam ... | 1999 | 10582888 |
| cloning and characterization of an aspergillus nidulans gene involved in the regulation of penicillin biosynthesis. | to identify regulators of penicillin biosynthesis, a previously isolated mutant of aspergillus nidulans (prg-1) which carried the trans-acting prga1 mutation was used. this mutant also contained fusions of the penicillin biosynthesis genes acva and ipna with reporter genes (acva-uida and ipna-lacz) integrated in a double-copy arrangement at the chromosomal argb gene. the prga1 mutant strain exhibited only 20 to 50% of the ipna-lacz and acva-uida expression exhibited by the wild-type strain and h ... | 1999 | 10583968 |
| regulation of the feruloyl esterase (faea) gene from aspergillus niger. | feruloyl esterases can remove aromatic residues (e.g., ferulic acid) from plant cell wall polysaccharides (xylan, pectin) and are essential for complete degradation of these polysaccharides. expression of the feruloyl esterase-encoding gene (faea) from aspergillus niger depends on d-xylose (expression is mediated by xlnr, the xylanolytic transcriptional activator) and on a second system that responds to aromatic compounds with a defined ring structure, such as ferulic acid and vanillic acid. sev ... | 1999 | 10584009 |
| primary cutaneous aspergillus nidulans infection associated with a hickman catheter in a patient with neutropenia. | | 1999 | 10585834 |
| in-vitro susceptibility of aspergillus spp. isolates to amphotericin b and itraconazole. | the mics of amphotericin b and itraconazole for 230 isolates of aspergillus spp., comprising 156 aspergillus fumigatus, 20 aspergillus terreus, 22 aspergillus flavus, 17 aspergillus nidulans and 15 aspergillus niger, were determined by a broth microdilution method with rpmi 1640 medium. no isolate was detected with an mic of amphotericin b >2 mg/l. itraconazole mics >16 mg/l were detected for four aspergillus fumigatus and one aspergillus nidulans isolates. | 1999 | 10588320 |
| catalase activity is necessary for heat-shock recovery in aspergillus nidulans germlings. | to understand the molecular mechanisms induced by stress that contribute to the development of tolerance in eukaryotic cells, the filamentous fungus aspergillus nidulans has been chosen as a model system. here, the response of a. nidulans germlings to heat shock is reported. the heat treatment dramatically increased the concentration of trehalose and induced the accumulation of mannitol and mrna from the catalase gene cata. both mannitol and catalase function to protect cells from different reac ... | 1999 | 10589732 |
| identification of catalytic residues in glyoxal oxidase by targeted mutagenesis. | glyoxal oxidase is a copper metalloenzyme produced by the wood-rot fungus phanerochaete chrysosporium as an essential component of its extracellular lignin degradation pathways. previous spectroscopic studies on glyoxal oxidase have demonstrated that it contains a free radical-coupled copper active site remarkably similar to that found in another fungal metalloenzyme, galactose oxidase. alignment of primary structures has allowed four catalytic residues of glyoxal oxidase to be targeted for site ... | 1999 | 10593910 |
| the human tfiid components taf(ii)135 and taf(ii)20 and the yeast saga components ada1 and taf(ii)68 heterodimerize to form histone-like pairs. | it has been previously proposed that the transcription complexes tfiid and saga comprise a histone octamer-like substructure formed from a heterotetramer of h4-like human htaf(ii)80 (or its drosophila melanogaster dtaf(ii)60 and yeast [saccharomyces cerevisiae] ytaf(ii)60 homologues) and h3-like htaf(ii)31 (dtaf(ii)40 and ytaf(ii)17) along with two homodimers of h2b-like htaf(ii)20 (dtaf(ii)30alpha and ytaf(ii)61/68). however, it has not been formally shown that htaf(ii)20 heterodimerizes via it ... | 2000 | 10594036 |
| interaction between developmental and cell cycle regulators is required for morphogenesis in aspergillus nidulans. | in aspergillus nidulans, mutation of the transcriptional regulator brla arrests formation of asexual spore-forming structures called conidiophores but does not hinder vegetative hyphal growth. during conidiophore development a 6-fold, brla-dependent increase in the kinase activities of nimx(cdc2) and nima occurs. a similar level of kinase induction was promoted by ectopic expression of brla. northern and western analysis revealed marked induction of nimx(cdc2) mrna after ectopic expression of br ... | 1999 | 10601021 |
| prr1, a homolog of aspergillus nidulans palf, controls ph-dependent gene expression and filamentation in candida albicans. | the ph of the environment has been implicated in controlling the yeast-hypha transition and pathogenesis of candida albicans. several c. albicans genes, including phr1 and phr2, are ph dependent in their expression. to investigate the mechanism of ph-dependent expression, we have cloned and characterized prr1 (for ph response regulator). prr1 is homologous to palf, a component of the ph response pathway in aspergillus nidulans. expression of prr1 was itself ph dependent, being maximal at acid ph ... | 1999 | 10601209 |
| effect of environmental ph on morphological development of candida albicans is mediated via the pacc-related transcription factor encoded by prr2. | the ability to respond to ambient ph is critical to the growth and virulence of the fungal pathogen candida albicans. this response entails the differential expression of several genes affecting morphogenesis. to investigate the mechanism of ph-dependent gene expression, the c. albicans homolog of pacc, designated prr2 (for ph response regulator), was identified and cloned. pacc encodes a zinc finger-containing transcription factor that mediates ph-dependent gene expression in aspergillus nidula ... | 1999 | 10601210 |
| [aortic rupture in invasive pulmonary aspergillosis in a neutropenic patient]. | | 1999 | 10605483 |
| role of water mobility on mold spore germination. | a sugar transport defected strain of aspergillus nidulans (bia-1 sora-2) was tested for spore germination in nutrient media containing various water activity (a(w)) values and varying amounts of non-nutritive, nontoxic carbohydrates (l-sorbose and cellulose). freeze-dried media [containing the same nutrient level but different in sorbose/cellulose (s:c) ratio] were adjusted to 0.75-0.97a(w) at 25 degrees c before inoculation. minimum a(w) for germination varied with s:c ratio. because both sorbo ... | 1999 | 10606561 |
| refined structures of oxidized flavodoxin from anacystis nidulans. | flavodoxin from anacystis nidulans (synechococcus pcc 7942) was the first member of the flavodoxin family to be characterized, and is the structural prototype for the "long-chain" flavodoxins that have molecular masses of approximately 20 kda. crystal structure analyses and refinements of three orthorhombic forms of oxidized a. nidulans flavodoxin are reported, and salient features of the fold and the fmn binding site are compared with other flavodoxins. the structure of form i (wild-type: p2121 ... | 1999 | 10610791 |
| comparisons of wild-type and mutant flavodoxins from anacystis nidulans. structural determinants of the redox potentials. | the long-chain flavodoxins, with 169-176 residues, display oxidation-reduction potentials at ph 7 that vary from -50 to -260 mv for the oxidized/semiquinone (ox/sq) equilibrium and are -400 mv or lower for the semiquinone/hydroquinone (sq/hq) equilibrium. to examine the effects of protein interactions and conformation changes on fmn potentials in the long-chain flavodoxin from anacystis nidulans (synechococcus pcc 7942), we have determined crystal structures for the semiquinone and hydroquinone ... | 1999 | 10610792 |
| metabolite repression and inducer exclusion in the proline utilization gene cluster of aspergillus nidulans. | the clustered prnb, prnc, and prnd genes are repressed by the simultaneous presence of glucose and ammonium. a derepressed mutation inactivating a crea-binding site acts in cis only on the permease gene (prnb) while derepression of prnd and prnc is largely the result of reversal of inducer exclusion. | 2000 | 10613888 |
| mitochondrial movement and morphology depend on an intact actin cytoskeleton in aspergillus nidulans. | mitochondria are essential organelles for the oxidative energy metabolism in eukaryotic cells. determinants of mitochondrial morphology as well as the machinery underlying their subcellular distribution are not well understood. in this study we constructed an aspergillus nidulans strain, in which mitochondria are stained with the green-fluorescent protein (gfp) to visualize them and study their behavior in vivo (http://www.uni-marburg. de/mpi/movies/mitochondria/mitochondria.html). mitochondria ... | 2000 | 10618165 |
| lack of host specialization in aspergillus flavus. | aspergillus spp. cause disease in a broad range of organisms, but it is unknown if strains are specialized for particular hosts. we evaluated isolates of aspergillus flavus, aspergillus fumigatus, and aspergillus nidulans for their ability to infect bean leaves, corn kernels, and insects (galleria mellonella). strains of a. flavus did not affect nonwounded bean leaves, corn kernels, or insects at 22 degrees c, but they killed insects following hemocoelic challenge and caused symptoms ranging fro ... | 2000 | 10618242 |
| requirement of monooxygenase-mediated steps for sterigmatocystin biosynthesis by aspergillus nidulans. | sterigmatocystin (st) and aflatoxin b(1) (afb(1)) are two polyketide-derived aspergillus mycotoxins synthesized by functionally identical sets of enzymes. st, the compound produced by aspergillus nidulans, is a late intermediate in the afb(1) pathway of a. parasiticus and a. flavus. previous biochemical studies predicted that five oxygenase steps are required for the formation of st. a 60-kb st gene cluster in a. nidulans contains five genes, stcb, stcf, stcl, stcs, and stcw, encoding putative m ... | 2000 | 10618248 |
| the chsa gene from aspergillus nidulans is necessary for maximal conidiation. | a fragment from the open reading frame of the cloned chsa gene from aspergillus nidulans was deleted and replaced with the argb gene. the resulting construct was used to replace the wild-type chsa gene in an argb deletion strain. the growth and morphology of the vegetative hyphae from the resulting chsa disruptant strain were indistinguishable from those of a wild-type strain but the chitin content of the hyphae from the disruptant was reduced to approximately 90% of that of wild-type. the disru ... | 2000 | 10620691 |
| pantothenate kinase regulation of the intracellular concentration of coenzyme a. | pantothenate kinase (pank) is the key regulatory enzyme in the coa biosynthetic pathway in bacteria and is thought to play a similar role in mammalian cells. we examined this hypothesis by identifying and characterizing two murine cdnas that encoded pank. the two cdnas were predicted to arise from alternate splicing of the same gene to yield different mrnas that encode two isoforms (mpank1alpha and mpank1beta) with distinct amino termini. the predicted protein sequence of mpank1 was not related ... | 2000 | 10625688 |
| wild-type and mutant alleles of the aspergillus nidulans developmental regulator gene brla: correlation of variant sites with protein function. | the dna sequences of two wild-type and eleven mutant alleles of the developmental regulator gene brla from aspergillus nidulans, which encodes a zinc-finger protein, were characterized. variant sites were located on rescued plasmids or pcr products based either on their meiotic map position or the use of denaturing gradient gel electrophoresis. mutations in three null mutants, one of which is partially suppressible, encode premature stop codons. two environmentally sensitive mutants were charact ... | 1999 | 10628875 |
| hypomorphic bima(apc3) alleles cause errors in chromosome metabolism that activate the dna damage checkpoint blocking cytokinesis in aspergillus nidulans. | the aspergillus nidulans sepi(+) gene has been implicated in the coordination of septation with nuclear division and cell growth. we find that the temperature-sensitive (ts) sepi1 mutation represents a novel allele of bima(apc3), which encodes a conserved component of the anaphase-promoting complex/cyclosome (apc/c). we have characterized the septation, nuclear division, cell-cycle checkpoint defects, and dna sequence alterations of sepi1 (renamed bima10) and two other ts lethal bima(apc3) allel ... | 2000 | 10628978 |
| sporulation at minimum specific growth rate in aspergillus nidulans chemostat culture predicted using protein synthesis efficiency estimations. | ribosomal efficiency (re) estimates provide a quantitative descriptor of intrinsic growth rate of cell populations using readily-obtainable experimental data. in aspergillus nidulans chemostat cultures, re increased linearly with growth rate over the range 25-60% of maximum growth rate (mu max), consistent with increasing ribosomal usage with increased growth rate. above 60%, re did not increase significantly, suggesting that all ribosomes were functional at 60% of mu max, further increases in g ... | 1999 | 10629970 |
| deletion of the unique gene encoding a typical histone h1 has no apparent phenotype in aspergillus nidulans. | we have cloned the h1 histone gene (hhoa) of aspergillus nidulans. this single-copy gene codes for a typical linker histone with one central globular domain. the open reading frame is interrupted by six introns. the position of the first intron is identical to that of introns found in some plant histones. an h1-gfp fusion shows exclusive nuclear localization, whereas chromosomal localization can be observed during condensation at mitosis. surprisingly, the deletion of hhoa results in no obvious ... | 2000 | 10632892 |
| isolation, purification, and characterization of a cold-active lipase from aspergillus nidulans. | aspergillus nidulans wg312 strain secreted lipase activity when cultured in liquid media with olive oil as carbon source. highest lipase productivity was found when the mycelium was grown at 30 degrees c in a rich medium. the new enzyme was purified to homogeneity from the extracellular culture of a. nidulans by phenyl-sepharose chromatography and affinity binding on linolenic acid-agarose. the lipase was monomeric with an apparent m(r) of 29 kda and a pi of 4.85 and showed no glycosylation. kin ... | 2000 | 10637060 |
| phenylalanine transport in aspergillus nidulans: demonstration of role of phenylalanine binding proteins. | crude shock proteins extracted by two stage osmotic shock were further purified by affinity chromatography to obtain ligand (phenylalanine) specific binding protein (phebip) a component of phenylalanine (phe) transport system from wild type and a phe transport mutant fpad11 of aspergillus nidulans. a new eluent 0.1 m tris-hcl containing 1.5 n nacl and 0.5 n na2co3, ph 8 was used during the investigation. the elution profile of mutant phebip exhibited one simple and two compound peaks instead of ... | 1999 | 10641135 |
| nmr solution structure of alcr (1-60) provides insight in the unusual dna binding properties of this zinc binuclear cluster protein. | the three-dimensional structure of the dna-binding domain (residues 1-60) of the ethanol regulon transcription factor alcr from aspergillus nidulans has been solved by nmr. this domain belongs to the zinc binuclear cluster class. although the core of the protein is similar to previously characterized structures, consisting of two helices organized around a zn(2)cys(6 )motif, the present structure presents important variations, among them the presence of two supplementary helices. this structure ... | 2000 | 10656785 |
| localization of wild type and mutant class i myosin proteins in aspergillus nidulans using gfp-fusion proteins. | we have examined the distribution of myoa, the class i myosin protein of the filamentous fungus aspergillus nidulans, as a gfp fusion protein. wild type gfp-myoa expressed from the myoa promoter is able to rescue a conditional myoa null mutant. growth of a strain expressing gfp-myoa as the only class i myosin was approximately 50% that of a control strain, demonstrating that the fusion protein retains substantial myosin function. the distribution of the wild type gfp-myoa fusion is enriched in g ... | 2000 | 10658211 |
| developmental and metabolic regulation of the phosphoglucomutase-encoding gene, pgmb, of aspergillus nidulans. | we have isolated the pgmb gene from aspergillus nidulans, which encodes a phosphoglucomutase, one of the key enzymes in carbohydrate metabolism. the pgmb gene is located on chromosome vii and its orf encodes 557 amino acids. mutant phenotypes were analysed by expression of high levels of pgmb antisense rna, which lead to a loss of detectable levels of sense rna. under conditions of antisense rna expression, a 30% reduction in the growth rate was observed in comparison to wild-type. on the enzyme ... | 2000 | 10660061 |
| the role of the rodlet structure on the physicochemical properties of aspergillus conidia. | physico-chemical properties of aspergillus conidia rely on their outer cell-wall rodlet layer. in a. fumigatus and a. nidulans, the rodlet structure is due to an hydrophobin encoded by homologous roda genes. to evaluate the role of the rodlet structure on the physico-chemical properties of conidia, we compared hydrophobicity, lewis acid-base (i.e. electron donor/acceptor) characteristics and electrostatic charge of hydrophobin-less (rodletless) mutant and wild-type conidia of a. fumigatus and a. ... | 1999 | 10664979 |
| on how a transcription factor can avoid its proteolytic activation in the absence of signal transduction. | in response to alkaline ambient ph, the aspergillus nidulans pacc transcription factor mediating ph regulation of gene expression is activated by proteolytic removal of a negative-acting c-terminal domain. we demonstrate interactions involving the approximately 150 c-terminal pacc residues and two regions located immediately downstream of the dna binding domain. our data indicate two full-length pacc conformations whose relative amounts depend upon ambient ph: one 'open' and accessible for proce ... | 2000 | 10675341 |
| the presence of gsi-like genes in higher plants: support for the paralogous evolution of gsi and gsii genes. | glutamine synthetase type i (gsi) genes have previously been described only in prokaryotes except that the fungus emericella nidulans contains a gene (flug) which encodes a protein with a large n-terminal domain linked to a c-terminal gsi-like domain. eukaryotes generally contain the type ii (gsii) genes which have been shown to occur also in some prokaryotes. the question of whether gsi and gsii genes are orthologues or paralogues remains a point of controversy. in this article we show that gsi ... | 2000 | 10684345 |
| molecular characterization of ubiquitin genes from aspergillus nidulans: mrna expression on different stress and growth conditions. | we are interested in studying the ubiquitin (ubi) gene expression during different stress and growth conditions in the filamentous fungus aspergillus nidulans. here, we report the cloning of a cdna clone that corresponds to a gene, ubi1, that encodes a carboxyl extension protein from a. nidulans. this cdna corresponds to a gene that encodes a protein that showed high homology to other polyubiquitin and cep-80 genes at the n- and c-terminus, respectively. we characterize the mrna expression of th ... | 2000 | 10684969 |
| carbon catabolite repression in plant pathogenic fungi: isolation and characterization of the gibberella fujikuroi and botrytis cinerea crea genes. | the crea genes of two plant pathogenic fungi, the gibberellin-producing rice pathogen gibberella fujikuroi and the gray mold botrytis cinerea, were isolated and characterized. the deduced amino acid sequences of both glucose repressors are 64% identical to each other and 59% (g. fujikuroi) and 61% (b. cinerea) identical to the crea protein of aspergillus nidulans. the zinc finger regions of the gibberella and botrytis crea proteins shared 98% identity with the corresponding zinc finger region of ... | 2000 | 10689158 |
| the pause software for analysis of translational control over protein targeting: application to e. nidulans membrane proteins. | the pause software has been developed as a new tool to study translational control over protein targeting. this makes it possible to correlate the position of clusters of rare codons in a gene, predicted to cause a translational pause, with the position of hydrophobic stretches in the encoded protein, predicted to span a membrane or to act as a cleavable signal for targeting to the secretory pathway. furthermore, this software gathers these correlations over whole sets of genes. the pause softwa ... | 2000 | 10689191 |
| nitrate assimilation genes of the marine diazotrophic, filamentous cyanobacterium trichodesmium sp. strain wh9601. | a 4.0-kb dna fragment of trichodesmium sp. strain wh9601 contained gene sequences encoding the nitrate reduction enzymes, nira and narb. a third gene positioned between nira and narb encodes a putative membrane protein with similarity to the nitrate permeases of bacillus subtilis (nasa) and emericella nidulans (crna). the gene was shown to functionally complement a deltanasa mutant of b. subtilis and was assigned the name napa (nitrate permease). napa was involved in both nitrate and nitrite upt ... | 2000 | 10692386 |
| catalase-peroxidases in cyanobacteria--similarities and differences to ascorbate peroxidases. | cyanobacteria (blue-green algae) are oxygenic phototrophic bacteria carrying out plant-type photosynthesis. the only hydrogen peroxide scavenging enzymes in at least two unicellular species have been demonstrated to be bifunctional cytosolic catalase-peroxidases (catpxs) having considerable homology at the active site with plant ascorbate peroxidases (apxs). in this paper we examined optical and kinetic properties of catpxs from the cyanobacteria anacystis nidulans and synechocystis pcc 6803 and ... | 1999 | 10694066 |
| molecular cloning and characterization of a glucan synthase gene from the human pathogenic fungus paracoccidioides brasiliensis. | 1,3-beta-d-glucan is a fungal cell wall polymer synthesized by the multi-subunit enzyme 1,3-beta-d-glucan synthase. a subunit of this integral membrane protein was first described as the product of the fks1 gene from saccharomyces cerevisiae using echinocandin mutants. other fks1 genes were also reported for candida albicans, aspergillus nidulans and cryptococcus neoformans. here, we report the nucleotide sequence of the first homologous fks gene cloned from the pathogenic fungus paracoccidioide ... | 2000 | 10705373 |
| transcriptional analysis of hydrogenase genes in the cyanobacteria anacystis nidulans and anabaena variabilis monitored by rt-pcr. | diverse cyanobacteria express an uptake hydrogenase, encoded by the genes hupsl, and a bidirectional, nad(p)(+)-reducing hydrogenase with the genes hox(e)fuyh. in the unicellular anacystis nidulans, the hox genes are organized on two separate loci, whereas they are contiguous in one cluster, though interspersed with two unidentified reading frames, orf 3 and 8, in the heterocystous anabaena variabilis. the hox gene clusters of these two cyanobacteria have now been transcriptionally analyzed by r ... | 2000 | 10706662 |
| an unambiguous microassay of galactofuranose residues in glycoconjugates using mild methanolysis and high ph anion-exchange chromatography. | an original, unambiguous microassay of galactofuranose (galf) residues in glycoconjugates is described. the method involves mild acid methanolysis (5 mm hcl) for 3 h at 84 degrees c followed by high ph anion-exchange chromatography using a routine monosaccharide system. the methanolysis products mealpha-galf and mebeta-galf were characterized chromatographically by comparison with the authentic compounds and by their response to treatment with mild acid and with beta-galactofuranosidase. testing ... | 2000 | 10706782 |
| a new approach for the identification and cloning of genes: the pbacwich system using cre/lox site-specific recombination. | with current plant transformation methods ( agrobacterium, biolistics and protoplast fusion), insertion of dna into the genome occurs randomly and in many instances at multiple sites. associated position effects, copy number differences and multigene interactions can make gene expression experiments difficult to interpret and plant phenotypes less predictable. an alternative approach to random integration of large dna fragments into plants is to utilize one of several site-specific recombination ... | 2000 | 10710436 |
| methylcitrate synthase from aspergillus nidulans: implications for propionate as an antifungal agent. | aspergillus nidulans was used as a model organism to investigate the fungal propionate metabolism and the mechanism of growth inhibition by propionate. the fungus is able to grow slowly on propionate as sole carbon and energy source. propionate is oxidized to pyruvate via the methylcitrate cycle. the key enzyme methylcitrate synthase was purified and the corresponding gene mcsa, which contains two introns, was cloned, sequenced and overexpressed in a. nidulans. the derived amino acid sequence of ... | 2000 | 10712680 |
| architectural transcription factors and the saga complex function in parallel pathways to activate transcription. | recent work has shown that transcription of the yeast ho gene involves the sequential recruitment of a series of transcription factors. we have performed a functional analysis of ho regulation by determining the ability of mutations in sin1, sin3, rpd3, and sin4 negative regulators to permit ho expression in the absence of certain activators. mutations in the sin1 (=spt2) gene do not affect ho regulation, in contrast to results of other studies using an ho:lacz reporter, and our data show that t ... | 2000 | 10713159 |
| thioesterase domain of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase: alteration of stereospecificity by site-directed mutagenesis. | the carboxy-terminal thioesterase domain of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase catalyzes the hydrolytic release of the tripeptide product (lld-acv). by site-directed mutagenesis an s3599a change was introduced into the highly conserved gxsxg motif, resulting in a more than 95 % decrease of penicillin production. purification of the modified multienzyme showed surprisingly only a 50 % reduction of the peptide formation rate, with the stereoisomer delta-(l-alpha-aminoadipy ... | 2000 | 10715209 |
| construction of an equalized cdna library from colletotrichum lagenarium and its application to the isolation of differentially expressed genes. | to establish an efficient screening system for differentially expressed genes of a phytopathogenic fungus colletotrichum lagenarium, we constructed an equalized (normalized) cdna library from c. lagenarium and used this library for differential screening. for the isolation of genes involved in infection-related developments of conidia, conidia undergoing appressorium differentiation were selected as the source of materials for construction of the cdna library. the equalization of cdna was perfor ... | 2000 | 10721483 |
| bordetella pertussis tonb, a bvg-independent virulence determinant. | in gram-negative bacteria, high-affinity iron uptake requires the tonb/exbb/exbd envelope complex to release iron chelates from their specific outer membrane receptors into the periplasm. based on sequence similarities, the bordetella pertussis tonb exbb exbd locus was identified on a cloned dna fragment. the tight organization of the three genes suggests that they are cotranscribed. a putative fur-binding sequence located upstream from tonb was detected in a fur titration assay, indicating that ... | 2000 | 10722583 |
| heterologous expression in aspergillus nidulans of a trichoderma longibrachiatum endoglucanase of enological relevance. | an aspergillus nidulans transformant expressing the trichoderma longibrachiatum endoglucanase 1 gene (egl1) has been constructed. the extracellular production of egl1 in different culture media has been studied, and a medium has been found in which egl1 is the predominant extracellular protein produced. the enzymatic properties of the heterologously produced egl1 are very similar to those of the native enzyme. grape maceration in the presence of culture filtrate enriched in egl1 resulted in incr ... | 2000 | 10725180 |
| evidence that the aspergillus nidulans class i and class ii chitin synthase genes, chsc and chsa, share critical roles in hyphal wall integrity and conidiophore development. | although many chitin synthase genes have been identified in a broad range of fungal species, there have been only a few reports about their role in fungal morphogenesis. in most cases, single gene disruption or replacement did not reveal their function, possibly because of functional redundancy among them. we obtained null mutants of aspergillus nidulans chsa and chsc genes encoding non-essential class ii and class i chitin synthases, respectively. the deltachsa deltachsc mutant exhibited growth ... | 2000 | 10731706 |
| stress-responsive gene expression in tetrahymena. | cells properly respond to extracellular stimuli and circumstantial environment. the unicellular eukaryotic protozoan tetrahymena is a potentially useful animal cell model system for studying the molecular mechanism of adaptation to environment. tetrahymena is exposed to fluctuations in temperature, ph, amounts of nutrients and concentration of dissolved gases in natural habitat. for example, the cells adapt to cold environment by increase in unsaturated fatty acids in membrane phospholipids to m ... | 1999 | 10735176 |
| a simple and rapid method for the preparation of a cell-free extract with ccaat-binding activity from filamentous fungi. | a simple and rapid method for the preparation of a cell-free extract with the ccaat-binding activity was established with aspergillus nidulans as a model fungus. proteins were extracted with 6 m guanidine hydrochloride directly from mycelia and renatured by dialysis. this method was found applicable to other filamentous fungi such as aspergillus oryzae and trichoderma viride. | 2000 | 10737212 |
| mutational analysis of tyrosine-191 in the catalysis of cephalosporium acremonium isopenicillin n synthase. | isopenicillin n synthase (ipns) is a key enzyme responsible for the catalytic conversion of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine (acv) to isopenicillin n in the beta-lactam antibiotic biosynthetic pathway. the aspergillus nidulans ipns crystal structure implicated amino acid residues tyrosine-189, arginine-279, and serine-281 in the substrate-binding of the valine carboxylate portion of acv via hydrogen bonds. in previous reports, we provided mutational evidence for the critical inv ... | 2000 | 10739949 |
| the aspergillus nidulans uvsb gene encodes an atm-related kinase required for multiple facets of the dna damage response. | in aspergillus nidulans, uvsb and uvsd belong to the same epistasis group of dna repair mutants. recent observations suggest that these genes are likely to control cell cycle checkpoint responses to dna damage and incomplete replication. consistent with this notion, we show here that uvsb is a member of the conserved family of atm-related kinases. phenotypic characterization of uvsb mutants shows that they possess defects in additional aspects of the dna damage response besides checkpoint contro ... | 2000 | 10747054 |
| identification of aspergillus species using internal transcribed spacer regions 1 and 2. | aspergillus species are the most frequent cause of invasive mold infections in immunocompromised patients. although over 180 species are found within the genus, 3 species, aspergillus flavus, a. fumigatus, and a. terreus, account for most cases of invasive aspergillosis (ia), with a. nidulans, a. niger, and a. ustus being rare causes of ia. the ability to distinguish between the various clinically relevant aspergillus species may have diagnostic value, as certain species are associated with high ... | 2000 | 10747135 |
| a comparative repair study of thymine- and uracil-photodimers with model compounds and a photolyase repair enzyme. | cyclobutane uridine and thymidine dimers with cis-syn-structure are dna lesions, which are efficiently repaired in many species by dna photolyases. the essential step of the repair reaction is a light driven electron transfer from a reduced fad cofactor (fadh ) to the dimer lesion, which splits spontaneously into the monomers. repair studies with uv-light damaged dna revealed significant rate differences for the various dimer lesions. in particular the effect of the almost eclipsed positioned me ... | 2000 | 10747389 |
| in vivo studies of upstream regulatory cis-acting elements of the alcr gene encoding the transactivator of the ethanol regulon in aspergillus nidulans. | the alcr gene of aspergillus nidulans, which encodes the specific transactivator of the ethanol utilization pathway, is positively autoregulated and carbon catabolite repressed. regulation by these two circuits occurs at the transcriptional level via the binding of the two regulators, alcr and crea, to their cognate targets respectively. we demonstrate here that out of two clustered putative alcr repeated consensus sequences, only the palindromic target is functional in vivo. hence, it is solely ... | 2000 | 10760169 |
| characterization of the aspergillus parasiticus major nitrogen regulatory gene, area. | the major nitrogen regulatory gene, area, was cloned from aspergillus parasiticus. it encoded a polypeptide of 864 amino acids which contained a nuclear localization signal (nls), a highly acidic region from positions 497 to 542, a cys-x(2)-cys-x(17)-cys-x(2)-cys dna-binding motif and a conserved carboxy-terminus. electrophoretic mobility shift assays suggested that the a. parasiticus area dna-binding domain fusion protein bound cooperatively to single gata elements in the a. parasiticus niad-ni ... | 2000 | 10760588 |
| a novel nuclear factor, sreb, binds to a cis-acting element, sre, required for inducible expression of the aspergillus oryzae taka-amylase a gene in a. nidulans. | the taka-amylase a gene (taag2) of aspergillus oryzae is inducibly expressed in a. nidulans upon exposure to inducing carbon sources, such as starch and maltose. in order to identify nuclear factor(s) possibly involved in the induction of the taag2 gene, gel mobility shift assays and dnase i footprinting analyses were carried out, and revealed a novel nuclear factor in a. nidulans extracts, which specifically bound to two sites in the taag2 promoter region, -204 to -189 and -182 to -168, which s ... | 2000 | 10778741 |
| on the mechanism by which alkaline ph prevents expression of an acid-expressed gene. | previous work has shown that zinc finger transcription factor pacc mediates the regulation of gene expression by ambient ph in the fungus aspergillus nidulans. this regulation ensures that the syntheses of molecules functioning in the external environment, such as permeases, secreted enzymes, and exported metabolites, are tailored to the ph of the growth environment. a direct role for pacc in activating the expression of an alkaline-expressed gene has previously been demonstrated, but the mechan ... | 2000 | 10779325 |
| using dna-tagged mutagenesis to improve heterologous protein production in aspergillus oryzae. | using dna-tagged mutagenesis to improve heterologous protein production in aspergillus oryzae. fungal genetics and biology 29, 28-37. restriction enzyme-mediated integration (remi) has been employed as a mutagen to generate two insertion libraries in an aspergillus oryzae strain expressing a thermomyces lanuginosus lipase. the remi libraries were created using linearized plasmid containing the a. oryzae pyrg and either bamhi or ecori enzyme. the libraries were screened for lipase production, and ... | 2000 | 10779397 |
| large-scale comparison of fungal sequence information: mechanisms of innovation in neurospora crassa and gene loss in saccharomyces cerevisiae. | we report a large-scale comparison of sequence data from the filamentous fungus neurospora crassa with the complete genome sequence of saccharomyces cerevisiae. n. crassa is considerably more morphologically and developmentally complex than s. cerevisiae. we found that n. crassa has a much higher proportion of "orphan" genes than s. cerevisiae, suggesting that its morphological complexity reflects the acquisition or maintenance of novel genes, consistent with its larger genome. our results also ... | 2000 | 10779483 |
| the analysis of the transcriptional activator prna reveals a tripartite nuclear localisation sequence. | nuclear localisation signals (nlss) have been classified as either mono- or bipartite. genetic analysis and gfp fusions show that the nls of a zn-binuclear cluster transcriptional activator of aspergillus nidulans (prna) is tripartite. this nls comprises two amino-terminal basic sequences and the first basic sequence of the zn-cluster. neither the two amino-terminal basic sequences nor the paradigmatic nucleoplasmin bipartite nls drive our construction to the nucleus. cryosensitive mutations in ... | 2000 | 10788322 |
| aspergillus stea (sterile12-like) is a homeodomain-c2/h2-zn+2 finger transcription factor required for sexual reproduction. | saccharomyces cerevisiae ste12p plays a key role in coupling signal transduction through map kinase modules to cell-specific or morphogenesis-specific gene expression required for mating and pseudohyphal (ph)/filamentous growth (fg). ste12p homologues in the pathogenic yeasts candida albicans and filobasidiela neoformans apparently play similar roles during dimorphic transitions. here we report the isolation and characterization of the first ste12 protein from a true filamentous fungus. aspergil ... | 2000 | 10792717 |
| heterotrimeric g-proteins of a filamentous fungus regulate cell wall composition and susceptibility to a plant pr-5 protein. | membrane permeabilizing plant defensive proteins first encounter the fungal cell wall that can harbor specific components that facilitate or prevent access to the plasma membrane. however, signal transduction pathways controlling cell wall composition in filamentous fungi are largely unknown. we report here that the deposition of cell wall constituents that block the action of osmotin (pr-5), an antifungal plant defense protein, against aspergillus nidulans requires the activity of a heterotrime ... | 2000 | 10792821 |
| ornithine decarboxylase of stagonospora (septoria) nodorum is required for virulence toward wheat. | a knockout strain of stagonospora (septoria) nodorum lacking the single ornithine decarboxylase (odc) allele has been created by targeted gene replacement. a central region of the s. nodorum odc gene was isolated by polymerase chain reaction using degenerate oligonucleotides and used to probe a lambda genomic library. the gene was sequenced and the encoded odc protein sequence was shown to be similar to those from other fungi. the functionality of the s. nodorum odc was confirmed by complementat ... | 2000 | 10799502 |
| the crystal structure and active site location of isocitrate lyase from the fungus aspergillus nidulans. | isocitrate lyase catalyses the first committed step of the carbon-conserving glyoxylate bypass, the mg(2+)-dependent reversible cleavage of isocitrate into succinate and glyoxylate. this metabolic pathway is an inviting target for the control of a number of diseases, because the enzymes involved in this cycle have been identified in many pathogens including mycobacterium leprae and leishmania. | 2000 | 10801489 |
| the nima-related kinase x-nek2b is required for efficient assembly of the zygotic centrosome in xenopus laevis. | nek2 is a mammalian cell cycle-regulated serine/threonine kinase that belongs to the family of proteins related to nima of aspergillus nidulans. functional studies in diverse species have implicated nima-related kinases in g(2)/m progression, chromatin condensation and centrosome regulation. to directly address the requirements for vertebrate nek2 kinases in these cell cycle processes, we have turned to the biochemically-tractable system provided by xenopus laevis egg extracts. following isolati ... | 2000 | 10806108 |
| cloning and characterization of avfa and omtb genes involved in aflatoxin biosynthesis in three aspergillus species. | the biosynthesis of aflatoxins (b(1), g(1), b(2), and g(2)) is a multi-enzyme process controlled genetically by over 20 genes. in this study, we report the identification and characterization of the avfa gene, which was found to be involved in the conversion of averufin (avf) to versiconal hemiacetal acetate (vha), in aspergillus parasiticus and a. flavus; a copy of avfa gene was also cloned from a non-aflatoxin producing strain a. sojae. complementation of an averufin-accumulating, non-aflatoxi ... | 2000 | 10806361 |
| interaction of human phagocytes with pigmentless aspergillus conidia. | a defect in the pksp gene of aspergillus fumigatus is associated with the loss of conidial pigmentation, a profound change of the conidial surface structure, and reduced virulence. the structural change of the conidial surface structure was not observed in similar a. nidulans wa mutants. our data indicate that the pigment of both species is important for scavenging reactive oxygen species and for protection of conidia against oxidative damage. | 2000 | 10816538 |
| taf-containing and taf-independent forms of transcriptionally active tbp in vivo. | transcriptional activity in yeast strongly correlates with promoter occupancy by general factors such as tata binding protein (tbp), tfiia, and tfiib, but not with occupancy by tbp-associated factors (tafs). thus, tbp exists in at least two transcriptionally active forms in vivo. the taf-containing form corresponds to the tfiid complex, whereas the form lacking tafs corresponds to tbp itself or to some other tbp complex. heat shock treatment altered the relative utilization of these tbp forms, w ... | 2000 | 10818000 |
| a spindle pole body-associated protein, snad, affects septation and conidiation in aspergillus nidulans. | the nuda1 mutation in the cytoplasmic dynein heavy chain gene inhibits nuclear migration, colony growth and asexual sporulation (conidiation) in the filamentous fungus aspergillus nidulans. it also alters the location of the first cell division event (septation) and prevents nucleation of tip cells. we showed previously that a suppressor of nuda1, snad290, partially reversed the nuclear migration defect and partially restored colony growth. we have now demonstrated that the snad290 mutation also ... | 2000 | 10821171 |
| ambient ph signalling in ascomycetous yeasts involves homologues of the aspergillus nidulans genes palf and paih. | in yarrowia lipolytica, the transcription factor rim101p mediates both ph regulation and control of mating and sporulation. like its homologues pacc of aspergillus nidulans and rim101p of saccharomyces cerevisiae, y1rim101p is activated by proteolytic c-terminal processing, which occurs in response to a signal transduced by a pathway involving several pal gene products. we report here the cloning and sequencing of two of these genes, pal2 and pal3. pal2 encodes a putative 632-residue protein wit ... | 2000 | 10821185 |
| amino acid residues n450 and q449 are critical for the uptake capacity and specificity of uapa, a prototype of a nucleobase-ascorbate transporter family. | specific carrier-mediated transport of purine and pyrimidine nucleobases across cell membranes is a basic biological process in both prokaryotes and eukaryotes. recent in silico analysis has shown that the aspergillus nidulans (uapa, uapc) and bacterial (pbux, uraa, pyrp) nucleobase transporters, and a group of mammalian l-ascorbic acid transporters (svct1 and svct2), constitute a unique protein family which includes putative homologues from archea, bacteria, plants and metazoans. the constructi ... | 2000 | 10824738 |
| ami1, an orthologue of the aspergillus nidulans apsa gene, is involved in nuclear migration events throughout the life cycle of podospora anserina. | the podospora anserina ami1-1 mutant was identified as a male-sterile strain. microconidia (which act as male gametes) form, but are anucleate. paraphysae from the perithecium beaks are also anucleate when ami1-1 is used as the female partner in a cross. furthermore, in crosses heterozygous for ami1-1, some crozier cells are uninucleate rather than binucleate. in addition to these nuclear migration defects, which occur at the transition between syncytial and cellular states, ami1-1 causes abnorm ... | 2000 | 10835387 |
| conidial germination in aspergillus nidulans requires ras signaling and protein synthesis. | the dormant spores of aspergillus nidulans become competent for growth and nuclear division in a process called conidial germination. to analyze the molecular details of conidial germination, we developed a genetic screen in which we identified spore germination-deficient mutants that are blocked in this process at the restrictive temperature. these mutants defined eight genes, of which we identified five. four of the five were directly involved in translation and protein folding, and the fifth ... | 2000 | 10835388 |
| dynamics of cytoplasmic dynein in living cells and the effect of a mutation in the dynactin complex actin-related protein arp1. | cytoplasmic dynein is a minus-end-directed microtubule motor that participates in multiple cellular activities such as organelle transport and mitotic spindle assembly [1]. to study the dynamic behavior of cytoplasmic dynein in the filamentous fungus aspergillus nidulans, we replaced the gene for the cytoplasmic dynein heavy chain, nuda, with a gene encoding a green fluorescent protein (gfp)-tagged chimera, gfp-nuda. the gfp-nuda fusion protein is fully functional in vivo: strains expressing onl ... | 2000 | 10837229 |
| structure-function analysis of nadph:nitrate reductase from aspergillus nidulans: analysis of altered pyridine nucleotide specificity in vivo. | nitrate reductase (nar) catalyses the reduction of nitrate to nitrite via a two-electron transfer. in fungi, the electron donor for nar is nadph whereas plants can have two enzymes, nadh:nar and a bispecific nad(p)h:nar. pcr mutagenesis was employed to introduce mutations into the niad gene of aspergillus nidulans in order to identify residues involved in co-enzyme specificity. the niad3000 mutation (niad t813d, k814q) altered co-enzyme specificity: the new enzyme had high levels of nadh:nar act ... | 2000 | 10846218 |
| confocal microscopy of fm4-64 as a tool for analysing endocytosis and vesicle trafficking in living fungal hyphae. | confocal microscopy of amphiphilic styryl dyes has been used to investigate endocytosis and vesicle trafficking in living fungal hyphae. hyphae were treated with fm4-64, fm1-43 or tma-dph, three of the most commonly used membrane-selective dyes reported as markers of endocytosis. all three dyes were rapidly internalized within hyphae. fm4-64 was found best for imaging the dynamic changes in size, morphology and position of the apical vesicle cluster within growing hyphal tips because of its stai ... | 2000 | 10849201 |
| the aspergillus nidulans crec gene involved in carbon catabolite repression encodes a wd40 repeat protein. | expression of many microbial genes required for the utilisation of less favoured carbon sources is carbon catabolite repressed in the presence of a preferred carbon source such as d-glucose. in aspergillus nidulans, crec mutants show derepression in the presence of d-glucose of some, but not all, systems normally subject to carbon catabolite repression. these mutants also fail to grow on some carbon sources, and show minor morphological impairment and altered sensitivity to toxic compounds inclu ... | 2000 | 10852476 |
| cloning and expression of the s-adenosylmethionine decarboxylase gene of neurospora crassa and processing of its product. | s-adenosylmethionine decarboxylase (adometdc) catalyzes the formation of decarboxylated adometdc, a precursor of the polyamines spermidine and spermine. the enzyme is derived from a proenzyme by autocatalytic cleavage. we report the cloning and regulation of the gene for adometdc in neurospora crassa, spe-2, and the effect of putrescine on enzyme maturation and activity. the gene was cloned from a genomic library by complementation of a spe-2 mutant. like other adometdcs, that of neurospora is d ... | 2000 | 10852489 |
| tagging of genes involved in multidrug resistance in aspergillus nidulans. | we have used a plasmid containing the neurospora crassa pyr4 gene to transform an aspergillus nidulans pyrg89 mutant strain in the presence of bam-hi, and isolated multidrug-sensitive mutants among the transformants. using this approach, we hoped to identify genes whose products are important for drug resistance by analyzing gene disruptions that alter the drug sensitivity of the cell. about 1300 transformants isolated following transformation were screened for sensitivity to drugs or various st ... | 2000 | 10852493 |
| mutation of a putative ampk phosphorylation site abolishes the repressor activity but not the nuclear targeting of the fungal glucose regulator cre1. | in filamentous ascomycetes, glucose repression is mediated by cre1, a zinc-finger protein related to miglp from yeast. five putative ampk phosphorylation motifs identified in the glucose repressor from the phytopathogenic fungus sclerotinia sclerotiorum were mutated in a gfp::cre1 translational fusion. complementation experiments in aspergillus nidulans and fluorescence microscopy analyses showed that mutation of one site (ser266) abolishes the repressor activity of the fusion protein but not it ... | 2000 | 10853770 |
| cloning and heterologous expression of solorina crocea pyrg. | a pyrg gene, encoding orotidine 5'-monophosphate decarboxylase, was cloned from a phage library derived from the lichen solorina crocea. phylogenetic analysis and a survey of geographically well-separated specimens were used to verify that the gene represented the fungal component of the lichen. both coding and upstream sequences of s. crocea pyrg exhibited features typical of fungal genes. a 132-bp intron interrupting the coding region between nucleotides 157 and 288 was confirmed by rt-pcr and ... | 2000 | 10853771 |
| molecular and physiological aspects of aflatoxin and sterigmatocystin biosynthesis by aspergillus tamarii and a. ochraceoroseus. | until recently, only three species (aspergillus flavus, a. parasiticus and a. nomius) have been widely recognized as producers of aflatoxin. in this study we examine aflatoxin production by two other species, a. tamarii and a. ochraceoroseus, the latter of which also produces sterigmatocystin. toxin-producing strains of a. tamarii and a. ochraceoroseus were examined morphologically, and toxin production was assayed on different media at different ph levels using thin layer chromatography and a d ... | 2000 | 10855723 |
| distinctive properties of the catalase b of aspergillus nidulans. | aspergillus nidulans catalase b (catb) was purified to homogeneity and characterized as a hydroperoxidase which resembles typical catalases in some physicochemical characteristics: (1) it has an apparent molecular weight of 360000 and is composed of four glycosylated subunits, (2) it has hydrophobic properties as revealed by extractability in ethanol/chloroform and binding to phenyl-superose, and (3) it has an acidic isoelectric point at ph 3. 5. also catb exhibits some distinctive properties, e ... | 2000 | 10858500 |
| nucleotide sequence and intron structure of the apocytochrome b gene of neurospora crassa mitochondria. | the sequence of the apocytochrome b (cob) gene of neurospora crassa has been determined. the structural gene is interrupted by two intervening sequences of approximately 1260 bp each. the polypeptide encoded by the exons shows extensive homology with the cob proteins of aspergillus nidulans and saccharomyces cerevisiae (79% and 60%, respectively). the two introns are, however, located at sites different from those of introns in the cob genes of a. nidulans and s. cerevisiae (which contain highly ... | 1983 | 10872314 |
| onychomycosis in malaysia. | the common etiological agents of onychomycosis are dermatophytes, molds and yeasts. a mycological nail investigation of onychomycosis using direct microscopy and culture was conducted by the mycology unit, department of medical microbiology, university of malaya from march 1996 to november 1998. the study involved 878 nail clippings or subungal scrapings from subjects with onychomycosis. on direct microscopy examination, 50% of the specimens were negative for fungal elements. on culture, 373 spe ... | 1999 | 10872513 |
| nuclear migration in fungi--different motors at work. | lower fungi such as saccharomyces cerevisiae and aspergillus nidulans are ideal organisms for studying the molecular biology underlying nuclear migration in eukaryotic cells. in this review, the role of different motor proteins such as dynein, kinesin and myosin will be discussed. | 2000 | 10875281 |
| the reliability of the aspergillus nidulans physical map. | here we report an evaluation of the aspergillus nidulans physical map (a cosmid contig map) emphasizing quantification and description of obvious mapping errors. classification and appraisal of mapping errors should be helpful to researchers working on particular regions of the map. we estimate between 47 (4.1%) and 63 (5.4%) probe/clone-linking errors. the majority of identified false links (38) permit reciprocal exchanges among linking clones located on disconnected mapping regions. the order ... | 2000 | 10882534 |
| analysis of two aspergillus nidulans genes encoding extracellular proteases. | characterization of prtadelta mutants, generated by gene disruption, showed that the prta gene is responsible for the majority of extracellular protease activity secreted by aspergillus nidulans at both neutral and acid ph. the prta delta mutation was used to map the prta gene to chromosome v. though aspartic protease activity has never been reported in a. nidulans and the prtadelta mutants appear to lack detectable acid protease activity, a gene (prtb) encoding a putative aspartic protease was ... | 2000 | 10882536 |
| biosynthesis of pyridoxine: origin of the nitrogen atom of pyridoxine in microorganisms. | the amide nitrogen atom of glutamine was incorporated into pyridoxine in four eukaryotes, emericella nidulans, mucor racemosus, neurospora crassa and saccharomyces cerevisiae, and two prokaryotes, staphylococcus aureus and bacillus subtilis, but not in the following prokaryotes, pseudomonas putida, enterobacter aerogenes and escherichia coli. on the other hand, the nitrogen atom of glutamate was incorporated into pyridoxine in p. putida, e. aerogenes and e. coli, but not in s. aureus and b. subt ... | 2000 | 10885790 |
| the tryptophan synthase-encoding trpb gene of aspergillus nidulans is regulated by the cross-pathway control system. | the tryptophan synthase-encoding gene, trpb, of aspergillus nidulans was cloned and characterized. it was mapped to chromosome i, between the gene meda, which is required for sexual and asexual development, and an orf encoding a protein with significant similarity to subunit b of vacuolar atp synthases. the 5' untranslated region was found to be at least 142 nucleotides (nt) long, the poly(a) addition site was localized at position + 216 relative to the stop codon by sequencing of several indepe ... | 2000 | 10905354 |
| a novel 'two-component' protein containing histidine kinase and response regulator domains required for sporulation in aspergillus nidulans. | we have characterised a-novel aspergillus nidulans gene encoding a 'two-component' signalling protein (tcsa). tcsa encodes both a histidine kinase domain and a response regulator domain similar to those found in bacterial, lower eukaryotic and plant members of the two-component family of proteins, while two pas domains in the amino-terminal region of the predicted tcsa product may monitor the signal which regulates a tcsa histidine kinase-response regulator phosphorelay. while tcsa is nonessenti ... | 2000 | 10905426 |
| an aspergillus oryzae ccaat-binding protein, aocp, is involved in the high-level expression of the taka-amylase a gene. | aspergillus oryzae contains a nuclear protein designated aocp, which binds specifically to a ccaat sequence in the promoter region of the a. oryzae taka-amylase a gene. a gene encoding a homologue of aspergillus nidulans hapc, a subunit of the a. nidulans ccaat binding complex, was isolated from a. oryzae and designated aohapc. aohapc comprises 215 amino acids and shows 84% identity to a. nidulans hapc. transformation of the a. nidulans hapc deletion strain with the aohapc gene restored the ccaa ... | 2000 | 10905428 |
| glucose dependent transcriptional expression of the cre1 gene in acremonium chrysogenum strains showing different levels of cephalosporin c production. | the cre1 gene from the beta-lactam producer acremonium chrysogenum has been isolated and characterized in order to study glucose-dependent gene expression in this biotechnically important fungus. the deduced protein sequence is highly similar to amino-acid sequences of other known glucose repressors from filamentous fungi, and carries conserved zinc-finger and regulatory motifs. contrary to cre gene expression in trichoderma reesei and aspergillus nidulans, the transcript level of the cre1 gene ... | 2000 | 10905429 |
| cloning and characterisation of a chitin synthase gene cdna from the cultivated mushroom agaricus bisporus and its expression during morphogenesis. | full-length cdna of a chitin synthase gene (chs1) was cloned from agaricus bisporus by screening a cdna library with a pcr amplified fragment of the chitin synthase gene. the chs1 contains an open reading frame of 2727 bp encoding a polypeptide of 909 amino acids and deduced molecular mass 102.3 kda and pi 8.23. the central region of chs1 showed strong homology to other fungal chitin synthase genes with seven conserved domains. it belongs to the chitin synthase class iii, analogous to chsb from ... | 2000 | 10913868 |
| ph regulation of gene expression in fungi. | a system for the regulation of gene expression by ambient (extracellular) ph was first identified in aspergillus nidulans. this system consists of the products of the pacc and pala, b, c, f, h, and i genes. pacc encodes a zinc finger transcription factor and these pal genes encode components of an ambient ph signal transduction pathway. ph regulatory systems have also been identified in other fungi. components of these regulatory systems are homologous to those in a. nidulans. this review descri ... | 2000 | 10919375 |
| a group of expressed cdna sequences from the wheat fungal leaf blotch pathogen, mycosphaerella graminicola (septoria tritici). | a group of expressed sequence tags (ests) from the wheat fungal pathogen mycosphaerella graminicola utilizing ammonium as a nitrogen source has been analyzed. single pass sequences of complementary dnas from 986 clones were determined. contig analysis and sequence comparisons allowed 704 unique ests (unigenes) to be identified, of which 148 appeared as multiple copies. searches of the nrdb95 protein database at embl using the blast2x algorithm revealed 407 (57.8%) sequences that generated high t ... | 2000 | 10919380 |
| prevalence and outcome of invasive fungal infections in 1,963 thoracic organ transplant recipients: a multicenter retrospective study. italian study group of fungal infections in thoracic organ transplant recipients. | fungal infections (fi) after solid organ transplantation (tx) remain a major cause of morbidity and mortality. aspergillus and candida account for more than 80% of fi. | 2000 | 10919584 |