Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| extragenic suppressors of the nimx2(cdc2) mutation of aspergillus nidulans affect nuclear division, septation and conidiation. | the aspergillus nidulans nimx(cdc2) protein kinase has been shown to be required for both the g(2)/m and g(1)/s transitions, and recent evidence has implicated a role for nimx(cdc2) in septation and conidiation. while much is understood of its g(2)/m function, little is known about the functions of nimx(cdc2) during g(1)/s, septation, and conidiophore development. in an attempt to better understand how nimx(cdc2) is involved in these processes, we have isolated four extragenic suppressors of the ... | 2000 | 11102358 |
| the aspergillus nidulans xprf gene encodes a hexokinase-like protein involved in the regulation of extracellular proteases. | the extracellular proteases of aspergillus nidulans are produced in response to limitation of carbon, nitrogen, or sulfur, even in the absence of exogenous protein. mutations in the a. nidulans xprf and xprg genes have been shown to result in elevated levels of extracellular protease in response to carbon limitation. the xprf gene was isolated and sequence analysis indicates that it encodes a 615-amino-acid protein, which represents a new type of fungal hexokinase or hexokinase-like protein. in ... | 2000 | 11102357 |
| landmarks in the early duplication cycles of aspergillus fumigatus and aspergillus nidulans: polarity, germ tube emergence and septation. | when the spores of filamentous fungi break dormancy, nuclear division is accompanied by a series of ordered morphological events including the switch from isotropic to polar growth, the emergence of a second germ tube from the conidium and septation. correlation of these morphological events with nuclear number allows them to serve as duplication cycle landmarks. early duplication cycle landmarks have been characterized in aspergillus nidulans, but not in other filamentous fungi. to learn more a ... | 2000 | 11101686 |
| studies of isopenicillin n synthase enzymatic properties using a continuous spectrophotometric assay. | isopenicillin n synthase (ipns) from aspergillus nidulans is a no-heme iron(ii)-dependent oxygenase which catalyses, in a single reaction, the bicyclisation of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine into isopenicillin n, the precursor of all other penicillins, cephalosporins and cephamycins. the ipns reaction can be followed directly and continuously by a new assay which monitors the absorbance increase at 235 nm characteristic of penicillin nucleus formation. using this assay, the ef ... | 2000 | 11094156 |
| iron starvation leads to increased expression of cu/zn-superoxide dismutase in aspergillus. | in a search for iron-regulated proteins of aspergillus nidulans and aspergillus fumigatus a 16-kda protein was identified which is about 5-fold upregulated during iron starvation in both species and which can be approximately 500-fold enriched by simple one-step chromatography on amberlite xad-16 resin. n-terminal protein sequence analysis and cloning of the respective a. nidulans cdna identified this protein as a cu/zn-superoxide dismutase (soda). northern analysis revealed that upregulation of ... | 2000 | 11094151 |
| a recq family dna helicase gene from aspergillus nidulans. | we have identified an aspergillus nidulans gene encoding a recq family helicase which we have therefore named recq. the a. nidulans recq protein is most closely related in sequence to human recq helicase 5. like the latter polypeptide, a. nidulans recq consists of little more than the conserved helicase domain, lacking the long amino- and carboxy-terminal extensions seen in other recq family members such as blm and wrn and in the sole recq family helicase of the yeast saccharomyces cerevisiae (s ... | 2000 | 11092746 |
| sconc, a gene involved in the regulation of sulphur metabolism in aspergillus nidulans, belongs to the skp1 gene family. | sconc, which encodes a negative regulator of sulphur metabolism in aspergillus nidulans was cloned, sequenced, and found to belong to the highly conserved family of skp1 genes essential for many cell functions, including cell cycle regulation. the orf of 722 bp, encoding a protein of 161 amino acids, is interrupted by four introns. there is a fifth intron (135 bp long) in the upstream untranslated sequence. two point mutations in conserved regions were identified in the mutant alleles sconc3 and ... | 2000 | 11085267 |
| a rapid method for efficient gene replacement in the filamentous fungus aspergillus nidulans. | the construction of mutant fungal strains is often limited by the poor efficiency of homologous recombination in these organisms. higher recombination efficiencies can be obtained by increasing the length of homologous dna flanking the transformation marker, although this is a tedious process when standard molecular biology techniques are used for the construction of gene replacement cassettes. here, we present a two-step technology which takes advantage of an escherichia coli strain expressing ... | 2000 | 11071951 |
| g-protein signalling mediates differential production of toxic secondary metabolites. | filamentous fungi elaborate a complex array of secondary metabolites, including antibiotics and mycotoxins. as many of these compounds pose significant economic and health concerns, elucidation of the underlying cellular mechanisms that control their production is essential. previous work revealed that synthesis of the carcinogenic mycotoxins sterigmatocystin (st) and aflatoxin (af) in aspergillus species is negatively controlled by fada, the alpha-subunit of a heterotrimeric g-protein. in sharp ... | 2000 | 11069688 |
| [detection of emericella nidulans from bedding materials in horse breeding environment and its significance as a causative agent of guttural pouch mycosis in horses]. | sixty-six new and used samples of horse bedding materials: 60 rice straws, 2 wheat straws, 2 timothy hays and 2 wood chips, were collected from horse breeding stables of 33 farms in japan and examined for the presence of emericella nidulans (e. nidulans; anam. aspergillus nidulans). the incidence of e. nidulans in the bedding materials was 75.8% and there was no significant difference in detection of the fungus between the new and used materials (25 out of the 33 samples, respectively). the grow ... | 2000 | 11064324 |
| sulfate assimilation in aspergillus terreus: analysis of genes encoding atp-sulfurylase and paps-reductase. | two genes for the sulfate assimilation pathway in aspergillus terreus were cloned. the genes sat (coding for paps-reductase) and sct (coding for atp-sulfurylase) form a small gene cluster. both genes are similar to their homologs in a. nidulans (sa and sc), penicillium chrysogenum (aps) and saccharomyces cerevisiae (met3 and met16). in the coding sequence of the sct gene, a typical non-functional aps-kinase-like domain is present. the sct gene is expressed in a. nidulans, but its expression ther ... | 2000 | 11057445 |
| functional analysis of the leader peptide of the yeast gene cpa1 and heterologous regulation by other fungal peptides. | the 25-amino-acid leader peptide present at the 5' end of yeast cpa1 mrna is responsible for the translational repression of that gene by arginine. we show here that the active domain of the yeast peptide is highly specific and extends over amino acids 6-23. the region between amino acids 6-21 is well conserved between similar peptides present upstream of cpa1-homologous genes in other fungi. the neurospora crassa arg-2 peptide represses the expression of cpa1, whereas the peptide from aspergill ... | 2000 | 11057443 |
| xylp promoter-based expression system and its use for antisense downregulation of the penicillium chrysogenum nitrogen regulator nre. | a highly inducible fungal promoter derived from the penicillium chrysogenum endoxylanase (xylp) gene is described. northern analysis and the use of a beta-glucuronidase (uida) reporter gene strategy showed that xylp expression is transcriptionally regulated. xylan and xylose are efficient inducers, whereas glucose strongly represses the promoter activity. comparison of the same expression construct as a single copy at the niad locus in p. chrysogenum and at the argb locus in aspergillus nidulans ... | 2000 | 11055928 |
| comparison of the sequences of the aspergillus nidulans hxb and drosophila melanogaster ma-l genes with nifs from azotobacter vinelandii suggests a mechanism for the insertion of the terminal sulphur atom in the molybdopterin cofactor. | the molybdopterin cofactor (mocf) is required for the activity of a variety of oxidoreductases. the xanthine oxidase class of molybdoenzymes requires the mocf to have a terminal, cyanolysable sulphur ligand. in the sulphite oxidase/nitrate reductase class, an oxygen is present in the same position. mutations in both the ma-l gene of drosophila melanogaster and the hxb gene of aspergillus nidulans result in loss of activities of all molybdoenzymes that necessitate a cyanolysable sulphur in the ac ... | 2000 | 11029694 |
| biolistic co-transformation of metarhizium anisopliae var. acridum strain cg423 with green fluorescent protein and resistance to glufosinate ammonium. | metarhizium anisopliae var. acridum (syn. m. flavoviride) is recognized as a highly specific and virulent mycopathogen of locusts and grasshoppers and is currently being developed as a biological control agent for this group of insects in brazil. intact conidia of m. anisopliae var. acridum strain cg423 were transformed using microparticle bombardment. plasmids used were: (1) pbarks1 carrying the bar gene of streptomyces hygroscopicus fused to the aspergillus nidulans trpc promoter, encoding res ... | 2000 | 11024271 |
| the aspergillus nidulans cysa gene encodes a novel type of serine o-acetyltransferase which is homologous to homoserine o-acetyltransferases. | the aspergillus nidulans cysa gene was cloned by functional complementation of the cysa1 mutation that impairs the synthesis of o:-acetylserine. the molecular nature of cysa1 and cysa103 alleles was characterized; a nucleotide substitution and a frame shift were found in the former and a deletion mutation in the latter. the cysa protein is 525 amino acids long and is encoded by an uninterrupted open reading frame. expression of the cysa gene appears not to be regulated by sulfur, carbon and nitr ... | 2000 | 11021945 |
| characterization and mapping of an informational suppressor in aspergillus nidulans. | the present work was undertaken to characterize a suppressor gene present in a mutant strain of a. nidulans obtained with ntg (n-methyl-n'-nitro-n-nitrosoguanidine). analyses of this mutant have shown that this suppressor, designated suo1, induces phenotypic co-reversion of several auxotrophic mutations and makes the strain sensitive to aminoglycoside antibiotics and lower temperatures. suo1 has shown to be on linkage group viii. the vegetative growth of the mutant strain is very unstable becaus ... | 2000 | 11021306 |
| the dna-binding domain of the gene regulatory protein area extends beyond the minimal zinc-finger region conserved between gata proteins. | the area protein of aspergillus nidulans regulates the activity of over 100 genes involved in the utilisation of nitrogen, and has a limited region of homology with the vertebrate family of gata proteins around a zinc finger (zf) motif. a 66 amino acid (a.a.) residue fragment (zf(66)) corresponding to the zinc finger, a 91 a.a fragment (zf(91)) containing an additional 25 a.a. at the c-terminus, and a much larger 728 a.a. sequence (3'ex) corresponding to the 3'exon have been over-expressed as fu ... | 2000 | 11018257 |
| protein expression and subcellular localization of the general purine transporter uapc from aspergillus nidulans. | the uapc gene of aspergillus nidulans belongs to a family of nucleobase-specific transporters conserved in prokaryotic and eucaryotic organisms. we report the use of immunological and green fluorescent protein based strategies to study protein expression and subcellular distribution of uapc. a chimeric protein containing a plant-adapted green fluorescent protein (sgfp) fused to the c-terminus of uapc was shown to be functional in vivo, as it complements a triple mutant (i.e., uapc(-) uapa(-) azg ... | 2000 | 11017766 |
| rapid and sensitive plate method for detection of aspergillus fumigatus. | the routine identification of aspergillus fumigatus in clinical samples involves, apart from direct examination, the isolation of the organism on a plate followed by its microscopic characterization. this approach lacks sensitivity, specificity, and speed. a new procedure has been developed combining microcolony formation on a nylon membrane filter at 45 degrees c with the detection of a specific 4-methylumbelliferyl-alpha-l-arabinopyranoside cleaving enzyme activity in digitonin permeabilized c ... | 2000 | 11015405 |
| development of a pcr-based line probe assay for identification of fungal pathogens. | we report on a reverse-hybridization line probe assay (lipa) which when combined with pcr amplification detects and identifies clinically significant fungal pathogens including candida, aspergillus, and cryptococcus species. dna probes have been designed from the internal transcribed-spacer (its) regions of candida albicans, candida parapsilosis, candida glabrata, candida tropicalis, candida krusei, candida dubliniensis, cryptococcus neoformans, aspergillus fumigatus, aspergillus versicolor, asp ... | 2000 | 11015393 |
| characterization of mrad18sc, a mouse homolog of the yeast postreplication repair gene rad18. | the rad18 gene of the yeast saccharomyces cerevisiae encodes a protein with ssdna binding activity that interacts with the ubiquitin-conjugating enzyme rad6 and plays an important role in postreplication repair. we identified and characterized the putative mouse homolog of rad18, designated mrad18sc. the mrad18sc open reading frame encodes a 509-amino-acid polypeptide that is strongly conserved in size and sequence between yeast and mammals, with specific conservation of the ring-zinc-finger and ... | 2000 | 11013078 |
| antisense silencing of the crea gene in aspergillus nidulans. | antisense expression of a portion of the gene encoding the major carbon catabolite repressor crea in aspergillus nidulans resulted in a substantial increase in the levels of glucose-repressible enzymes, both endogenous and heterologous, in the presence of glucose. the derepression effect was approximately one-half of that achieved in a null crea mutant. unlike results for that mutant, however, growth parameters and colony morphology in the antisense transformants were not affected. | 2000 | 11010922 |
| characterization of two putative histone deacetylase genes from aspergillus nidulans. | in eukaryotic organisms, acetylation of core histones plays a key role in the regulation of transcription. multiple histone acetyltransferases (hats) and histone deacetylases (hdacs) maintain a dynamic equilibrium of histone acetylation. the latter form a highly conserved protein family in many eukaryotic species. in this paper, we report the cloning and sequencing of two putative histone deacetylase genes (rpda, hosa) of aspergillus nidulans, which are the first to be analyzed from filamentous ... | 2000 | 11004483 |
| structural and functional analysis of mutations in alkaptonuria. | alkaptonuria (aku), the prototypic inborn error of metabolism, was the first human disease to be interpreted as a mendelian trait by garrod and bateson at the beginning of last century. aku results from impaired function of homogentisate dioxygenase (hgo), an enzyme required for the catabolism of phenylalanine and tyrosine. with the novel 7 aku and 22 fungal mutations reported here, a total of 84 mutations impairing this enzyme have been found in the hgo gene from humans and model organisms. for ... | 2000 | 11001939 |
| identification and characterization of two ca2+/cam-dependent protein kinases required for normal nuclear division in aspergillus nidulans. | we utilized an expression screen to identify two novel ca(2+)/calmodulin (cam)-regulated protein kinases in aspergillus nidulans. the two kinases, cmkb and cmkc, possess high sequence identity with mammalian cam kinases (camks) i/iv and camkkalpha/beta, respectively. in vitro cmkc phosphorylates and increases the activity of cmkb, indicating they are biochemical homologues of camkkalpha/beta and camki/iv. the disruption of cmkb is lethal; however, when protein expression is postponed, the spores ... | 2000 | 10988293 |
| the catabolite inactivation of aspergillus nidulans isocitrate lyase occurs by specific autophagy of peroxisomes. | in aspergillus nidulans, activity of the glyoxylate cycle enzyme isocitrate lyase is finely regulated. isocitrate lyase is induced by growth on c2 compounds and long-chain fatty acids and repressed by glucose. in addition, activity of isocitrate lyase is subject to a second mechanism of catabolite control, glucose-induced inactivation. here, we demonstrate that the catabolite inactivation of a. nidulans isocitrate lyase, a process that takes place during glucose adaptation of cells grown under g ... | 2000 | 10985743 |
| a high affinity fungal nitrate carrier with two transport mechanisms. | we have expressed the crna high affinity nitrate transporter from emericella (aspergillus) nidulans in xenopus oocytes and used electrophysiology to study its properties. this method was used because there are no convenient radiolabeled substrates for the transporter. oocytes injected with crna mrna showed nitrate-, nitrite-, and chlorite-dependent currents. although the gene was originally identified by chlorate selection there was no evidence for transport of this anion. the gene selection is ... | 2000 | 10984478 |
| cloning of a sugar utilization gene cluster in aspergillus parasiticus. | at one end of the 70 kb aflatoxin biosynthetic pathway gene cluster in aspergillus parasiticus and aspergillus flavus reported earlier, we have cloned a group of four genes that constitute a well-defined gene cluster related to sugar utilization in a. parasiticus: (1) sugr, (2) hxta, (3) glca and (4) nada. no similar well-defined sugar gene cluster has been reported so far in any other related aspergillus species such as a. flavus, a. nidulans, a. sojae, a. niger, a. oryzae and a. fumigatus. the ... | 2000 | 10978525 |
| mitotic histone h3 phosphorylation by the nima kinase in aspergillus nidulans. | phosphorylation of histone h3 serine 10 correlates with chromosome condensation and is required for normal chromosome segregation in tetrahymena. this phosphorylation is dependent upon activation of the nima kinase in aspergillus nidulans. nima expression also induces ser-10 phosphorylation inappropriately in s phase-arrested cells and in the absence of nimx(cdc2) activity. at mitosis, nima becomes enriched on chromatin and subsequently localizes to the mitotic spindle and spindle pole bodies. t ... | 2000 | 10975520 |
| characterization of the class i alpha-mannosidase gene family in the filamentous fungus aspergillus nidulans. | we describe the cloning and sequence characterization of three class i alpha-1,2-mannosidase genes from the filamentous fungus aspergillus nidulans. we used degenerate pcr primers to amplify a portion of the alpha-1,2-mannosidase ia gene and used the pcr fragment to isolate the 2495 nt genomic gene plus several hundred bases of flanking region. putative introns were confirmed by rt-pcr. coding regions of the genomic sequence were used to identify two additional members of the gene family by blas ... | 2000 | 10974561 |
| a defined sequence within the 3' utr of the area transcript is sufficient to mediate nitrogen metabolite signalling via accelerated deadenylation. | nitrogen metabolism in aspergillus nidulans is regulated by area, a member of the gata family of transcription factors. one mechanism that modulates area activity involves the rapid degradation of the area transcript when sufficient nh4+ or gln are available. this signalling mechanism has been shown to require a region of 218 nucleotides within the 3' untranslated region of area mrna. we demonstrate that this region functions independently in a heterologous transcript and acts to accelerate degr ... | 2000 | 10972840 |
| purification and characterization of an alpha-l-rhamnosidase from aspergillus nidulans. | an enzyme exhibiting alpha-l-rhamnosidase activity was purified by fractionating a culture filtrate of aspergillus nidulans grown on l-rhamnose as the sole carbon source. the alpha-l-rhamnosidase was shown to be n-glycosylated and had a molecular mass of 102 kda, of which approximately 7% was contributed by carbohydrate. the enzyme, optimally active at ph 4.5-6 and 60 degrees c, had an isoelectric point of 5. with rho-nitrophenyl-alpha-l-rhamnopyranoside as the substrate it showed km and vmax va ... | 2000 | 10972728 |
| isolation and characterization of two evolutionarily conserved murine kinases (nek6 and nek7) related to the fungal mitotic regulator, nima. | entrance and exit from mitosis in aspergillus nidulans require activation and proteolysis, respectively, of the nima (never in mitosis, gene a) serine/threonine kinase. four different nima-related kinases were reported in mammals (nek1-4), but none of them has been shown to perform mitotic functions related to those demonstrated for nima. we describe here the isolation of two novel murine protein kinase genes, designated nek6 and nek7, which are highly similar to each other (87% amino acid ident ... | 2000 | 10964517 |
| molecular responses to changes in the environmental ph are conserved between the fungal pathogens candida dubliniensis and candida albicans. | in this work we cloned cdphr1 and cdphr2 from the human fungal pathogen candida dubliniensis. the two genes are homologues to the ph-regulated genes phr1 and phr2 from candida albicans. the ph-dependent pattern of expression of cdphr1 and cdphr2 was conserved in c. dubliniensis. cdphr1 could be shown to be functionally equivalent to phr1. the ph-regulated mode of expression was maintained when cdphr1 was integrated in c. albicans. this indicates a fundamentally similar mode of expressional regul ... | 2000 | 10959725 |
| preferential accessibility of the yeast his3 promoter is determined by a general property of the dna sequence, not by specific elements. | yeast promoter regions are often more accessible to nuclear proteins than are nonpromoter regions. as assayed by hinfi endonuclease cleavage in living yeast cells, hinfi sites located in the promoters of all seven genes tested were 5- to 20-fold more accessible than sites in adjacent nonpromoter regions. hinfi hypersensitivity within the his3 promoter region is locally determined, since it was observed when this region was translocated to the middle of the ade2 structural gene. detailed analysis ... | 2000 | 10958664 |
| fungal transporters involved in efflux of natural toxic compounds and fungicides. | survival of microorganisms in natural environments is favored by the capacity to produce compounds toxic to competing organisms and the ability to resist the effects of such toxic compounds. both factors contribute to a competitive advantage of organisms in ecosystems. all organisms have evolved active transport mechanisms by which endogenous and exogenous toxicants can be secreted. two major classes of transporter proteins are the atp-binding cassette (abc) and the major facilitator superfamily ... | 2000 | 10955904 |
| the role of abc transporters from aspergillus nidulans in protection against cytotoxic agents and in antibiotic production. | this paper describes the characterization of atrc and atrd (abc transporters c and d), two novel abc transporter-encoding genes from the filamentous fungus aspergillus nidulans, and provides evidence for the involvement of atrd in multidrug transport and antibiotic production. blast analysis of the deduced amino acid sequences of atrcp and atrdp reveals high homology to abc transporter proteins of the p-glycoprotein cluster. atrdp shows a particularly high degree of identity to the amino acid se ... | 2000 | 10954082 |
| molecular cloning and characterization of a gene encoding glutaminase from aspergillus oryzae. | a glutaminase from aspergillus oryzae was purified and its molecular weight was determined to be 82,091 by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. purified glutaminase catalysed the hydrolysis not only of l-glutamine but also of d-glutamine. both the molecular weight and the substrate specificity of this glutaminase were different from those reported previously [yano et al. (1998) j ferment technol 66: 137-143]. on the basis of its internal amino acid sequen ... | 2000 | 10952006 |
| pyrithiamine resistance gene (ptra) of aspergillus oryzae: cloning, characterization and application as a dominant selectable marker for transformation. | a pyrithiamine (pt) resistance gene (ptra) was cloned from a genomic dna library prepared from a pt resistant mutant of aspergillus oryzae. it conferred high resistance to pt on an a. oryzae industrial strain as well as a. nidulans. nucleotide sequence analysis showed that the ptra gene contained one intron (58-bp) and encodes 327 amino acid (aa) residues. additionally, the deduced aa sequence has 72% and 63% identity to fusarium solani sti35 encoding a stress-inducible protein and saccharomyces ... | 2000 | 10945258 |
| isolation of replicational cue elements from a library of bent dnas of aspergillus oryzae. | two fragments that could function as replicational cue elements were isolated from a genomic dna digest of aspergillus oryzae on the basis of abnormal behavior in polyacrylamide gel electrophoresis. the vector used in this study contained a scaffold-associated region of the drosophila melanogaster ftz gene to provide nuclear retention. neither fragment contained a yeast ars consensus sequence or an eukaryotic topoisomerase ii binding sequence. one of the fragments showed sequence homology with t ... | 2000 | 10939521 |
| insertion of the line retrotransposon mgl causes a conidiophore pattern mutation in magnaporthe grisea. | we obtained three magnaporthe grisea morphological mutants that had the line transposon mgl inserted into the acr1 locus. sequence analysis revealed that acr1 is homologous to meda, a developmental regulator of aspergillus nidulans conidiation. these results demonstrated that mgl elements could transpose and cause insertional mutagenesis in m. grisea. | 2000 | 10939262 |
| the abc transporter atrb from aspergillus nidulans mediates resistance to all major classes of fungicides and some natural toxic compounds. | this paper reports the functional characterization of atrbp, an abc transporter from aspergillus nidulans. atrbp is a multidrug transporter and has affinity to substrates belonging to all major classes of agricultural fungicides and some natural toxic compounds. the substrate profile of atrbp was determined by assessing the sensitivity of deletion and overexpression mutants of atrb to several toxicants. all mutants showed normal growth as compared to control isolates. deltaatrb mutants displayed ... | 2000 | 10931903 |
| the lis1-related nudf protein of aspergillus nidulans interacts with the coiled-coil domain of the nude/ro11 protein. | the nudf gene of the filamentous fungus aspergillus nidulans acts in the cytoplasmic dynein/dynactin pathway and is required for distribution of nuclei. nudf protein, the product of the nudf gene, displays 42% sequence identity with the human protein lis1 required for neuronal migration. haploinsufficiency of the lis1 gene causes a malformation of the human brain known as lissencephaly. we screened for multicopy suppressors of a mutation in the nudf gene. the product of the nude gene isolated in ... | 2000 | 10931877 |
| c-jun and rack1 homologues regulate a control point for sexual development in aspergillus nidulans. | amino acid limitation results in impaired sexual fruit body formation in filamentous fungi such as aspergillus nidulans. the starvation signal is perceived by the cross-pathway regulatory network controlling the biosynthesis of translational precursors and results in increased expression of a transcriptional activator encoded by a c-jun homologue. in the presence of amino acids, the gene product of the mammalian rack1 homologue cpcb is required to repress the network. growth under amino acid sta ... | 2000 | 10931303 |
| morphogenesis in aspergillus nidulans requires dopey (dopa), a member of a novel family of leucine zipper-like proteins conserved from yeast to humans. | dopa is the founding member of a novel protein family required for correct cell morphology and spatiotemporal organization of multicellular structures in the filamentous fungus aspergillus nidulans. dopa homologues from saccharomyces cerevisiae (dop1), candida albicans, caenorhabditis elegans, rattus norvegicus and homo sapiens have been identified from genome sequencing projects. s. cerevisiae dop1 is essential for viability and, like dopa, affects cellular morphogenesis. dopa encodes a large p ... | 2000 | 10931277 |
| increased transformation efficiency of aspergillus nidulans protoplasts in the presence of dithiothreitol. | 2000 | 10929816 | |
| identification of domains responsible for signal recognition and transduction within the qutr transcription repressor protein. | qutr (qutr-encoded transcription-repressing protein) is a multi-domain repressor protein active in the signal-transduction pathway that regulates transcription of the quinic acid utilization (qut) gene cluster in aspergillus nidulans. in the presence of quinate, production of mrna from the eight genes of the qut pathway is stimulated by the activator protein quta (quta-encoded transcription-activating protein). mutations in the qutr gene alter qutr function such that the transcription of the qut ... | 2000 | 10926843 |
| identification of a candida albicans homologue of the pho85 gene, a negative regulator of the pho system in saccharomyces cerevisiae. | in a screen for the protein kinase genes of the human pathogenic yeast candida albicans, a putative homologue (capho85) of pho85, a negative regulator of the pho system of saccharomyces cerevisiae, which is one of the cyclin-dependent protein kinases (cdks), was isolated. an open reading frame (orf) of this gene was identified encoding a predicted protein of 326 amino acids with a calculated molecular weight of 37.6 kda. the amino acid sequence is highly homologous to s. cerevisiae pho85 (62% id ... | 2000 | 10923026 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |