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virulence comparisons of aspergillus nidulans mutants are confounded by the inflammatory response of p47phox-/- mice.while investigating the requirement for phagosomal alkalinization in the host defense against pulmonary aspergillosis, we observed high morbidity of p47(phox)(-/-) mice infected with ph-insensitive aspergillus nidulans mutants despite a paucity of fungal growth. fatal infection also resulted from a normally avirulent p-aminobenzoate auxotroph. this demonstrates that p47(phox)(-/-) murine immunity contributes significantly to a. nidulans lethality. these data have wider implications for microbial ...200516041040
convergent evolution of hydroxylation mechanisms in the fungal kingdom: molybdenum cofactor-independent hydroxylation of xanthine via alpha-ketoglutarate-dependent dioxygenases.the xanthine oxidases and dehydrogenases are among the most conserved enzymes in all living kingdoms. they contain the molybdopterin cofactor moco. we show here that in the fungi, in addition to xanthine dehydrogenase, a completely different enzyme is able to catalyse the oxidation of xanthine to uric acid. in aspergillus nidulans this enzyme is coded by the xana gene. we have cloned the xana gene and determined its sequence. a deletion of the gene has the same phenotype as the previously known ...200515948966
swi/snf-gcn5-dependent chromatin remodelling determines induced expression of gdh3, one of the paralogous genes responsible for ammonium assimilation and glutamate biosynthesis in saccharomyces cerevisiae.it is accepted that saccharomyces cerevisiae genome arose from complete duplication of eight ancestral chromosomes; functionally normal ploidy was recovered because of the massive loss of 90% of duplicated genes. there is evidence that indicates that part of this selective conservation of gene pairs is compelling to yeast facultative metabolism. as an example, the duplicated nadp-glutamate dehydrogenase pathway has been maintained because of the differential expression of the paralogous gdh1 and ...200515948967
isolation and characterization of the aspergillus nidulans eglc gene encoding a putative beta-1,3-endoglucanase.the aspergillus nidulans eglc gene, which encodes a putative beta-1,3-endoglucanase, was isolated from a chromosome-specific library by using an expressed sequence tag, esd0113. the eglc open reading frame encodes a 465 amino acid polypeptide, of which the amino acid sequence showed 46% similarity to that of saccharomyces cerevisiae beta-1,3-endoglucanase. the eglc transcript level at the early stages of asexual and sexual developments was dependent on the presence of the nsdd gene that encodes ...200515950156
occurrence of fungal species and mycotoxins from decayed sugarcane (saccharrum officinarum) in egypt.seventy-three fungal species belonging to forty-three genera were isolated from 40 samples of saccharrum officinarum (collected from naage-hamadi canal in qena governorate, egypt). aspergillus, trichoderma, mucor and pythium were the most common genera on the two isolation media. the dominant species of aspergillus were a. niger, a. flavus, a. ustus, a. terreus and a. wentii. some species were dominant on 40 g/l sucrose such as aspergillus niger, a. flavus, emericella nidulans, trichoderma virid ...200524049478
presence of a mannoprotein, mnpap, in the hyphal cell wall of aspergillus nidulans.the presence of a mannoprotein, mnpap, in the hyphal cell wall of aspergillus nidulans was examined by immunogold electron microscopy using a mnpa-null mutant as a negative control. the hyphal cell wall of wild type consisted of two layers-an electron-dense smooth outer layer and an electron-translucent inner layer-while the hyphal cell wall of the mnpa-null mutant had an electron-dense irregular outer layer together with the electron-translucent inner layer. in wild type, mnpap was present thro ...200421148828
increased conidiation associated with progression along the sterigmatocystin biosynthetic pathway.the aspergillus nidulans sterigmatocystin (st) gene cluster contains both regulatory (aflr) and biosynthetic genes (stc genes) required for st production. a total of 26 genes are in the cluster, 13 of which have been assigned a known function in the biosynthetic pathway. this complex secondary pathway represents a physiological cost to the fungus. we tested the amount of asexual spore production using a series of isogenic lines of a. nidulans, differing only in a mutation in aflr (resulting in a ...200421148941
transformation of fusarium oxysporum by particle bombardment and characterisation of the resulting transformants expressing a gfp transgene.fusarium is the causative agent of a variety of economically significant vascular wilt diseases of vegetables, flowers and field crops. the completion of the first fusarium genome and the availability of an est database now provides a platform for both forward and reverse genetic approaches to ascribe gene function in this phytopathogen. to underpin these strategies effective gene transfer procedures will be required. here we describe an efficient and robust procedure for fusarium oxysporum tran ...200415702267
parameiosis in aspergillus nidulans in response to doxorubicin.the recombinagenic effect of doxorubicin (an anticancer agent that impairs dna synthesis and causes chromosome breaks) was used to induce parameiotic events in aspergillus nidulans. heterokaryons formed with master strains and uvs mutants were inoculated with and without doxorubicin. haploid segregants (parameiotics and parents) and aneuploids were selected as heterokaryon-derived visible sectors. among parameiotic segregants, recombinants by intergenic mitotic crossing-over and recombinants by ...200415881406
synthesis and biological evaluations of sulfa derivatives bearing heterocyclic moieties.some new sulfa derivatives bearing a heterocyclic moieties fural, pyrimidinone, thiazolidinone, benzimidazole and 1,2,4-triazinone and the related compounds 2-19 have been synthesized from treatment of sulfa drugs with thioisocyanate, acid chlorides, 3-chloro-1,2,4-triazines, aldehydes, esters and/or 2-methylbenzoxazole followed by ring closure reactions. structures of the products have been deduced from their elemental analysis and spectral data. significant antimicrobial activities were observ ...200415881802
regulation of penicillin biosynthesis in filamentous fungi.the beta-lactam antibiotic penicillin is one of the mainly used antibiotics for the therapy of infectious diseases. it is produced as end product by some filamentous fungi only, most notably by aspergillus (emericella) nidulans and penicillium chrysogenum. the penicillin biosynthesis is catalysed by three enzymes which are encoded by the following three genes: acva (pcbab), ipna (pcbc) and aata (pende). the genes are organised into a gene cluster. although the production of secondary metabolites ...200415719552
crea-mediated carbon catabolite repression of beta-galactosidase formation in aspergillus nidulans is growth rate dependent.carbon catabolite repression by the crea-transcriptional repressor is widespread in filamentous fungi, but the mechanism by which glucose triggers carbon catabolite repression is still poorly understood. we investigated the hypothesis that the growth rate on glucose may control crea-dependent carbon catabolite repression by using glucose-limited chemostat cultures and the intracellular beta-galactosidase activity of aspergillus nidulans, which is repressed by glucose, as a model system. chemosta ...200415158274
[fatal aspergillus nidulans pneumonia]. 200415777589
ferrichrome in schizosaccharomyces pombe--an iron transport and iron storage compound.schizosaccharomyces pombe has been assumed not to produce siderophores. nevertheless, the genomic sequence of this fission yeast revealed the presence of siderophore biosynthetic genes for hydroxamates. applying a bioassay based on an aspergillus nidulans strain deficient in siderophore biosynthesis, and using reversed-phase hplc and mass spectrometry analysis, we demonstrate that s. pombe excretes and accumulates intracellularly the hydroxamate-type siderophore ferrichrome. under iron-limiting ...200415689108
a phylogenomic approach to reconstructing the diversification of serine proteases in fungi.using a phylogenomic approach with 10 fungi of very different virulence and habitat, we determined that there was substantial diversification of subtilase-type proteases early in ascomycete history (with subsequent loss in many lineages) but with no comparable diversification of trypsins. patterns of intron loss and the degree of divergence between paralogues demonstrated that the proliferation of proteinase k subtilases and subtilisin type subtilases seen in pathogenic ascomycetes (metarhizium ...200415525405
fostua, encoding a basic helix-loop-helix protein, differentially regulates development of three kinds of asexual spores, macroconidia, microconidia, and chlamydospores, in the fungal plant pathogen fusarium oxysporum.the soil-borne fungus fusarium oxysporum causes vascular wilt of a wide variety of plant species. f. oxysporum produces three kinds of asexual spores, macroconidia, microconidia, and chlamydospores. falcate macroconidia are formed generally from terminal phialides on conidiophores and rarely from intercalary phialides on hyphae. ellipsoidal microconidia are formed from intercalary phialides on hyphae. globose chlamydospores with thick walls are developed by the modification of hyphal and conidia ...200415590816
plasmid vectors for protein production, gene expression and molecular manipulations in aspergillus niger.we constructed three sets of plasmids for use in aspergillus niger. these plasmids were assembled using various combinations of a series of modular dna cassettes that included a selectable marker, pyrg, derived from aspergillus nidulans; two promoter regions for directing protein expression; a cassette derived from the ama1 replicator sequence to support autonomous replication; and a reporter gene based on the a. niger laca gene. one set included integrating and autonomously replicating plasmids ...200415848224
in silico reconstruction of nutrient-sensing signal transduction pathways in aspergillus nidulans.we report here probable nutrient-sensing signal transduction pathways in aspergillus nidulans, a model filamentous fungus, based on sequence homology studies with known saccharomyces cerevisiae and schizosaccharomyces pombe proteins. specifically, we identified a. nidulans homologs for yeast proteins involved in (1) filamentation-invasion, (2) camp-pka, (3) pheromone response, (4) cell integrity and (5) tor signaling pathways. we have also studied autophagy, one of the most important cellular re ...200415752076
local induction of the alc gene switch in transgenic tobacco plants by acetaldehyde.the alc promoter system, derived from the filamentous fungi aspergillus nidulans, allows chemically regulated gene expression in plants and thereby the study of gene function as well as metabolic and developmental processes. in addition to ethanol, this system can be activated by acetaldehyde, described as the physiological inducer in a. nidulans. here, we show that in contrast to ethanol, acetaldehyde allows tissue-specific activation of the alc promoter in transgenic tobacco plants. soil drenc ...200415574832
cloning and use of sc as homologous marker for aspergillus niger transformation.the sc sequence from aspergillus niger was cloned and developed into a homologous marker system for genetic transformation. the coding region of the sc gene amplified by pcr from the a. niger genome was provided with aspergillus nidulans expression signals (gpda promoter and trpc terminator). this chimeric construct was used to successfully transform a spontaneous sc- isolate of a. niger to prototrophy. the transformants analyzed by southern analysis showed integration of multiple copies of the ...200415722148
patterns of intron gain and loss in fungi.little is known about the patterns of intron gain and loss or the relative contributions of these two processes to gene evolution. to investigate the dynamics of intron evolution, we analyzed orthologous genes from four filamentous fungal genomes and determined the pattern of intron conservation. we developed a probabilistic model to estimate the most likely rates of intron gain and loss giving rise to these observed conservation patterns. our data reveal the surprising importance of intron gain ...200415562318
recent advances in the characterization of ambient ph regulation of gene expression in filamentous fungi and yeasts.all microorganisms must adapt to the ph of their environment. one aspect of this adaptation, particularly important for organisms that grow over a wide ph range, is the ability to express appropriately genes whose roles ultimately involve functions at the cell surface or in the environment. genes encoding permeases, secreted enzymes, enzymes involved in synthesis of exported metabolites such as toxins and antibiotics, and probably enzymes modifying secreted proteins posttranslationally all fall ...200415487944
gas-inducible transgene expression in mammalian cells and mice.we describe the design and detailed characterization of a gas-inducible transgene control system functional in different mammalian cells, mice and prototype biopharmaceutical manufacturing. the acetaldehyde-inducible alcr-p(alca) transactivator-promoter interaction of the aspergillus nidulans ethanol-catabolizing regulon was engineered for gas-adjustable transgene expression in mammalian cells. fungal alcr retained its transactivation characteristics in a variety of mammalian cell lines and reve ...200415502819
expression of a cephalosporin c esterase gene in acremonium chrysogenum for the direct production of deacetylcephalosporin c.a recombinant fungal microorganism capable of producing deacetylcephalosporin c was constructed by transforming a cephalosporin c esterase gene from rhodosporidium toruloides into acremonium chrysogenum. the cephalosporin c esterase gene can be expressed from its endogenous r. toruloides promoter or from the aspergillus nidulans trpc promoter under standard acremonium chrysogenum fermentation conditions. the expression of an active cephalosporin c esterase enzyme in a. chrysogenum results in the ...200415672283
connection of propionyl-coa metabolism to polyketide biosynthesis in aspergillus nidulans.propionyl-coa is an intermediate metabolite produced through a variety of pathways including thioesterification of propionate and catabolism of odd chain fatty acids and select amino acids. previously, we found that disruption of the methylcitrate synthase gene, mcsa, which blocks propionyl-coa utilization, as well as growth on propionate impaired production of several polyketides-molecules typically derived from acetyl-coa and malonyl-coa-including sterigmatocystin (st), a potent carcinogen, an ...200415514053
[antibiotic properties of some species of genus aspergillus mich].antibiotic activity screening of some species of genus aspergillus (64 strains) to different test-organisms (gram positive, gram negative, phytopathogenic bacteria and yeasts) has been carried out. the researched strains a. parvulus, a. ochraceus, a. ustus, a. versicolor, a.fumigatus, a. niger, a. deflectus, a. clavatus were characterized by a wide spectrum of antibiotic activity; the strains a. flavipes, a. sydowii, a. terreus, a. flavus, a. nidulans, a. alliaceus, a. fluticulosus were characte ...200415515902
regulation of aflatoxin synthesis by fada/camp/protein kinase a signaling in aspergillus parasiticus.analysis of fada and pkaa mutants in the filamentous fungus aspergillus nidulans demonstrated that fada (galpha) stimulates cyclic amp (camp)-dependent protein kinase a (pka) activity resulting, at least in part, in inhibition of conidiation and sterigmatocystin (st) biosynthesis. in contrast, camp added to the growth medium stimulates aflatoxin (af) synthesis in aspergillus parasiticus. our goal was to explain these conflicting reports and to provide mechanistic detail on the role of fada, camp ...200415518351
unusual transcription regulation of the niad gene under anaerobic conditions supporting fungal ammonia fermentation.the niad gene of the fungus aspergillus nidulans encodes an assimilatory nitrate reductase and exogenous ammonium represses its expression. under anoxic conditions, however, a. nidulans expressed niad even in the presence of ammonium and used the gene product for dissimilatory nitrate reduction (ammonia fermentation). this transcription regulation mechanism under anaerobiosis is critical for the fungus to ferment ammonium.200415118339
nek2a interacts with mad1 and possibly functions as a novel integrator of the spindle checkpoint signaling.chromosome segregation in mitosis is orchestrated by protein kinase signaling cascades. a biochemical cascade named spindle checkpoint ensures the spatial and temporal order of chromosome segregation during mitosis. here we report that spindle checkpoint protein mad1 interacts with nek2a, a human orthologue of the aspergillus nidulans nima kinase. mad1 interacts with nek2a in vitro and in vivo via a leucine zipper-containing domain located at the c terminus of mad1. like mad1, nek2a is localized ...200414978040
a putative g protein-coupled receptor negatively controls sexual development in aspergillus nidulans.g protein-coupled receptors (gpcrs) are key components of heterotrimeric g protein-mediated signalling pathways that detect environmental signals and confer rapid cellular responses. to broaden our understanding of signalling mechanisms in the filamentous fungus aspergillus nidulans, intensive analyses of the aspergillus nidulans genome have been carried out and nine genes (gpra approximately gpri) that are predicted to encode seven transmembrane spanning gpcrs have been identified. six of nine ...200414982628
novel polyketide synthase from nectria haematococca.we identified a polyketide synthase (pks) gene, pksn, from a strain of nectria haematococca by complementing a mutant unable to synthesize a red perithecial pigment. pksn encodes a 2,106-amino-acid polypeptide with conserved motifs characteristic of type i pks enzymatic domains: beta-ketoacyl synthase, acyltransferase, duplicated acyl carrier proteins, and thioesterase. the pksn product groups with the aspergillus nidulans wa-type pkss involved in conidial pigmentation and melanin, bikaverin, an ...200415128560
the neurospora crassa cfp promoter drives a carbon source-dependent expression of transgenes in filamentous fungi.the objective of the present study was to determine the potential of promoter sequences from the cfp gene of neurospora crassa to drive the expression of transgenes in filamentous fungi.200415139917
disruption of the gene encoding the v-atpase subunit a results in inhibition of normal growth and abolished sporulation in aspergillus nidulans.the authors have previously reported on molecular responses of aspergillus nidulans to bacterial antifungal metabolites, e.g. bafilomycins and the related concanamycins. these compounds are known inhibitors of v-atpases and cause dramatic effects on mycelial growth and morphology. in neurospora crassa, studies have shown that disruption of the gene encoding subunit a of the v-atpase results in morphological changes and reduced growth similar to those observed after addition of concanamycin. this ...200414993324
the pho80-like cyclin of aspergillus nidulans regulates development independently of its role in phosphate acquisition.in saccharomyces cerevisiae, phosphate acquisition enzymes are regulated by a cyclin-dependent kinase (pho85), a cyclin (pho80), the cyclin-dependent kinase inhibitor pho81, and the helix-loop-helix transcription factor pho4 (the pho system). previous studies in aspergillus nidulans indicate that a pho85-like kinase, phoa, does not regulate the classic pho system but regulates development in a phosphate-dependent manner. a pho80-like cyclin has now been isolated through its interaction with phoa ...200415247298
effect of vitamin e on autolysis and sporulation of aspergillus nidulans.the morphologic and physiologic effects of vitamin e, a powerful antioxidant, on the autolysis and sporulation of aspergillus nidulans fgsc26 were studied. in carbon-depleted submerged cultures, reactive oxygen species (ros) accumulated in the cells and, concomitantly, progressing autolysis was observed, which was characterized by decreasing dry cell masses and pellet diameters as well as by increasing extracellular chitinase activities. vitamin e supplemented at a concentration of 1 g/l hindere ...200415304761
influence of fadag203r and deltaflba mutations on morphology and physiology of submerged aspergillus nidulans cultures.morphologic and physiologic changes taking place in carbon-limited submerged cultures of aspergillus nidulans deltaflba and fadag203r strains were studied. loss-of-function mutation of the flba gene resulted in an altered germination with unusually thick germination tubes, "fluffy" pellet morphology, as well as a reduced fragmentation rate of hyphae during autolysis. in the fadag203r mutant strain, conidiophores formed in the stationary phase of growth, and the size of pellets shrank considerabl ...200415304762
the kip3-like kinesin kipb moves along microtubules and determines spindle position during synchronized mitoses in aspergillus nidulans hyphae.kinesins are motor proteins which are classified into 11 different families. we identified 11 kinesin-like proteins in the genome of the filamentous fungus aspergillus nidulans. relatedness analyses based on the motor domains grouped them into nine families. in this paper, we characterize kipb as a member of the kip3 family of microtubule depolymerases. the closest homologues of kipb are saccharomyces cerevisiae kip3 and schizosaccharomyces pombe klp5 and klp6, but sequence similarities outside ...200415189985
a role for cred, a carbon catabolite repression gene from aspergillus nidulans, in ubiquitination.in aspergillus nidulans, it is known that creb encodes a deubiquitinating enzyme that forms a complex with the wd40 motif containing protein encoded by crec, that mutations in these genes lead to altered carbon source utilization and that the cred34 mutation suppresses the phenotypic effects of mutations in crec and creb. therefore, cred was characterized in order to dissect the regulatory network that involves the creb-crec deubiquitination complex. cred contains arrestin domains and py motifs ...200415255903
on the mechanism of action of the antifungal agent propionate.propionate is used to protect bread and animal feed from moulds. the mode of action of this short-chain fatty acid was studied using aspergillus nidulans as a model organism. the filamentous fungus is able to grow slowly on propionate, which is oxidized to acetyl-coa via propionyl-coa, methylcitrate and pyruvate. propionate inhibits growth of a. nidulans on glucose but not on acetate; the latter was shown to inhibit propionate oxidation. when grown on glucose a methylcitrate synthase deletion mu ...200415265042
introns and splicing elements of five diverse fungi.genomic sequences and expressed sequence tag data for a diverse group of fungi (saccharomyces cerevisiae, schizosaccharomyces pombe, aspergillus nidulans, neurospora crassa, and cryptococcus neoformans) provided the opportunity to accurately characterize conserved intronic elements. an examination of large intron data sets revealed that fungal introns in general are short, that 98% or more of them belong to the canonical splice site (ss) class (5'gu...ag3'), and that they have polypyrimidine tra ...200415470237
the ganb galpha-protein negatively regulates asexual sporulation and plays a positive role in conidial germination in aspergillus nidulans.we isolated the ganb gene encoding the galpha-protein homolog from aspergillus nidulans. to investigate the cellular function of ganb, various mutant strains were isolated. deletion of constitutively inactive ganb mutants showed conidiation and derepressed brla expression in a submerged culture. constitutive activation of ganb caused a reduction in hyphal growth and a severe defect in asexual sporulation. we therefore propose that ganb may negatively regulate asexual sporulation through the brla ...200415280244
molecular cloning and characterization of a cdna encoding the n-acetyl-beta-d-glucosaminidase homologue of paracoccidioides brasiliensis.a cdna encoding the n-acetyl-beta-d-glucosaminidase (nag) protein of paracoccidioides brasiliensis, pb nag1, was cloned and characterized. the 2663-nucleotide sequence of the cdna consisted of a single open reading frame encoding a protein with a predicted molecular mass of 64.73 kda and an isoeletric point of 6.35. the predicted protein includes a putative 30-amino-acid signal peptide. the protein as a whole shares considerable sequence similarity with 'classic' nag. the primary sequence of pb ...200415283239
rapid differentiation of aspergillus species from other medically important opportunistic molds and yeasts by pcr-enzyme immunoassay.we developed a pcr-based assay to differentiate medically important species of aspergillus from one another and from other opportunistic molds and yeasts by employing universal, fungus-specific primers and dna probes in an enzyme immunoassay format (pcr-eia). oligonucleotide probes, directed to the internal transcribed spacer 2 region of ribosomal dna from aspergillus flavus, aspergillus fumigatus, aspergillus nidulans, aspergillus niger, aspergillus terreus, aspergillus ustus, and aspergillus v ...200415297489
the metarhizium anisopliae trp1 gene: cloning and regulatory analysis.the trp1 gene from the entomopathogenic fungus metarhizium anisopliae, cloned by heterologous hybridization with the plasmid carrying the trpc gene from aspergillus nidulans, was sequence characterized. the predicted translation product has the conserved catalytic domains of glutamine amidotransferase (g domain), indoleglycerolphosphate synthase (c domain), and phosphoribosyl anthranilate isomerase (f domain) organized as nh2-g-c-f-cooh. the orf is interrupted by a single intron of 60 nt that is ...200415297933
synthesis and antimicrobial activity of some netropsin analogues.nine novel lexitropsins were synthesized by linking two netropsin-like moieties through three different dicarboxylic acids; 9,10-dihydro-2,7-phenanthrenedicarboxylic acid; [(3-[[(carboxymethyl)amino]carbonyl]benzoyl)amino]acetic acid and indole-2,5-dicarboxylic acid. the netropsin residues were modified by the use of n-isopentylpyrrole, 5-methylthiophene or 5-isopropylthiazole heterocyclic building blocks in place of the usual n-methylpyrrole. the compounds were tested against five gram-positive ...200415505717
molecular cloning and functional characterization of avab, a gene encoding vam6p/vps39p-like protein in aspergillus nidulans.it has been demonstrated that saccharomyces cerevisiae vam6p/vps39p plays a critical role in the tethering steps of vacuolar membrane fusion by facilitating guanine nucleotide exchange on small guanosine triphosphatase (gtpase) vam4p/ypt7p. we report here the identification and characterization of a novel protein in aspergillus nidulans, avab, that exhibits similarity to vam6p/vps39p and plays a critical role in vacuolar morphogenesis in a. nidulans. avab is comprised of 1058 amino acids with am ...200415019743
the lipid body protein, ppoa, coordinates sexual and asexual sporulation in aspergillus nidulans.the coexistence of sexual and asexual reproductive cycles within the same individual is a striking phenomenon in numerous fungi. in the fungus aspergillus nidulans (teleomorph: emericella nidulans) endogenous oxylipins, called psi factor, serve as hormone-like signals that modulate the timing and balance between sexual and asexual spore development. here, we report the identification of a. nidulans ppoa, encoding a putative fatty acid dioxygenase, involved in the biosynthesis of the linoleic aci ...200414699095
the lis1-related protein nudf of aspergillus nidulans and its interaction partner nude bind directly to specific subunits of dynein and dynactin and to alpha- and gamma-tubulin. 200414712821
enzyme reactions and genes in aflatoxin biosynthesis.aflatoxins are highly toxic and carcinogenic substances mainly produced by aspergillus flavus and aspergillus parasiticus. sterigmatocystin is a penultimate precursor of aflatoxins and also a toxic and carcinogenic substance produced by many species, including aspergillus nidulans. recently, the majority of the enzyme reactions involved in aflatoxin/sterigmatocystin biosynthesis have been clarified, and the genes encoding the enzymes have been isolated. most of the genes constitute a large gene ...200415022028
synthesis and antifungal properties of compounds which target the alpha-aminoadipate pathway.fungi synthesize lysine via the alpha-aminoadipate pathway, which is not found in plants or animals. this pathway has been proposed as a target for antifungal agents, but until now no reports have appeared to test this proposal. hampering studies on the susceptibility of filamentous fungi such as those of the clinically important genus aspergillus is the fact that growth quantitation is notoriously difficult. we have used the recently-reported xtt-based method of biomass quantitation to measure ...200415025175
the aspergillus nidulans amds gene as a marker for the identification of multicopy t-dna integration events in agrobacterium-mediated transformation of aspergillus awamori.the aspergillus nidulans amds selection marker was used for the identification of multicopy t-dna insertions in agrobacterium-mediated transformation of asp. awamori. the selection of transformants on agar plates containing acetamide as sole nitrogen source and hygromycin resulted in a six-fold decrease in the transformation frequency, compared with the transformation frequency obtained after hygromycin selection alone. however, it was found that 47% of the transformants obtained after hygromyci ...200415045526
cremophor el stimulates mitotic recombination in uvsh//uvsh diploid strain of aspergillus nidulans.cremophor el is a solubilizer and emulsifier agent used in the pharmaceutical and foodstuff industries. the solvent is the principal constituent of paclitaxel's clinical formulation vehicle. since mitotic recombination plays a crucial role in multistep carcinogenesis, the study of the recombinagenic potential of chemical compounds is of the utmost importance. in our research genotoxicity of cremophor el has been studied by using an uvsh//uvsh diploid strain of aspergillus nidulans. since it spen ...200415048194
structure and biological functions of fungal cerebrosides.ceramide monohexosides (cmhs, cerebrosides) are glycosphingolipids composed of a hydrophobic ceramide linked to one sugar unit. in fungal cells, cmhs are very conserved molecules consisting of a ceramide moiety containing 9-methyl-4,8-sphingadienine in amidic linkage to 2-hydroxyoctadecanoic or 2-hydroxyhexadecanoic acids, and a carbohydrate portion consisting of one residue of glucose or galactose. 9-methyl 4,8-sphingadienine-containing ceramides are usually glycosylated to form fungal cerebros ...200415048196
fungal ammonia fermentation, a novel metabolic mechanism that couples the dissimilatory and assimilatory pathways of both nitrate and ethanol. role of acetyl coa synthetase in anaerobic atp synthesis.fungal ammonia fermentation is a novel dissimilatory metabolic mechanism that supplies energy under anoxic conditions. the fungus fusarium oxysporum reduces nitrate to ammonium and simultaneously oxidizes ethanol to acetate to generate atp (zhou, z., takaya, n., nakamura, a., yamaguchi, m., takeo, k., and shoun, h. (2002) j. biol. chem. 277, 1892-1896). we identified the aspergillus nidulans genes involved in ammonia fermentation by analyzing fungal mutants. the results showed that assimilatory ...200414722082
aspergillus fumigatus rasa and rasb regulate the timing and morphology of asexual development.expression of rasa plays an important role in conidial germination in aspergillus nidulans. conidial germination is required to initiate both infection and asexual development in the opportunistic pathogen aspergillus fumigatus. therefore, we sought to determine the requirements for ras proteins in conidial germination and asexual development of a. fumigatus. a second homolog, rasb, has been identified that characterizes a new subclass of ras genes. dominant active (da) and dominant negative (dn ...200414732259
a putative high affinity hexose transporter, hxta, of aspergillus nidulans is induced in vegetative hyphae upon starvation and in ascogenous hyphae during cleistothecium formation.fungi employ different carbohydrate uptake systems to adapt to certain environmental conditions and to different carbon source concentrations. the hydrolysis of polymeric carbohydrates and the subsequent uptake of monomeric forms may also play a role in development. aspergillus nidulans accumulates cell wall components during vegetative growth and degrades them during sexual development. we have identified the hxta (high affinity hexose transporter) gene in a differential library, which was enri ...200414732261
selection arena in aspergillus nidulans.the selection arena hypothesis states that overproduction of zygotes--a widespread phenomenon in animals and plants--can be explained as a mechanism of progeny choice. as a similar mechanism, the ascomycetous fungus aspergillus nidulans may overproduce dikaryotic fruit initials, hereafter called dikaryons. then, progeny choice might involve selection on which of these dikaryons will thrive to produce thousands of zygotes. these zygotes each produce eight sexual spores which together fill up one ...200414732264
osteomyelitis due to aspergillus spp. in patients with chronic granulomatous disease: comparison of aspergillus nidulans and aspergillus fumigatus.chronic granulomatous disease (cgd) is a rare inherited disorder of nadph oxidase in which phagocytes fail to generate reactive antimicrobial oxidants. invasive fungal infections are an important cause of morbidity and mortality in cgd patients, with aspergillus spp. being the most frequent fungal pathogens. we reviewed the reported cases of osteomyelitis in cgd patients due to aspergillus nidulans and compared them with those due to aspergillus fumigatus.200414732328
meab is a component of the methylmalonyl-coa mutase complex required for protection of the enzyme from inactivation.adenosylcobalamin-dependent methylmalonyl-coa mutase catalyzes the interconversion of methylmalonyl-coa and succinyl-coa. in humans, deficiencies in the mutase lead to methylmalonic aciduria, a rare disease that is fatal in the first year of life. such inherited deficiencies can result from mutations in the mutase structural gene or from mutations that impair the acquisition of cobalamins. recently, a human gene of unknown function, mmaa, has been implicated in methylmalonic aciduria (dobson, c. ...200414734568
negative selection using thymidine kinase increases the efficiency of recovery of transformants with targeted genes in the filamentous fungus leptosphaeria maculans.a vector system was constructed that is designed to decrease the number of transformants required to be screened when looking for gene disruption events in filamentous fungi. this vector was used to mutate two genes, an atp-binding cassette transporter ( lmabct4) and a two-component histidine kinase gene ( lmhk1) in the ascomycete leptosphaeria maculans. the system uses the thymidine kinase gene from the herpes simplex virus as a negative selectable marker. thymidine kinase expression is regulat ...200414749893
the azga purine transporter of aspergillus nidulans. characterization of a protein belonging to a new phylogenetic cluster.the azga gene of aspergillus nidulans encodes a hypoxanthine-adenine-guanine transporter. it has been cloned by a novel transposon methodology. the null phenotype of azga was defined by a number of mutations, including a large deletion. in mycelia, the azga gene is, like other genes of purine catabolism, induced by uric acid and repressed by ammonium. its transcription depends on the pathway-specific uay zinc binuclear cluster protein and the broad domain area gata factor. azga is not closely re ...200414597637
nuclear migration and positioning in filamentous fungi.genetic analyses of nuclear distribution mutants have indicated that functions of the microtubule motor, cytoplasmic dynein, and its regulators are important for nuclear positioning in filamentous fungi. here we review these studies and also present the need to further dissect how dynein and its associated microtubule cytoskeleton are involved mechanistically in nuclear positioning in the multinucleated hyphae.200414998524
the early impact of genetics on our understanding of cell cycle regulation in aspergillus nidulans.the application of genetic analysis was crucial to the rapid progress that has been made in cell cycle research. ron morris, one of the first to apply genetics to cell cycle research, developed aspergillus nidulans into an important model system for the analysis of many aspects of cell biology. within the area of cell cycle research, ron's laboratory is noted for development of novel cell biological and molecular genetic approaches as well as seminal insights regarding the regulation of mitosis, ...200414998523
tubulins in aspergillus nidulans.the discovery and characterization of the tubulin superfamily in aspergillus nidulans is described. remarkably, the genes that encode alpha-, beta-, and gamma-tubulins were all identified first in a. nidulans. there are two alpha-tubulin genes, tuba and tubb, two beta-tubulin genes, bena and tubc, and one gamma-tubulin gene, mipa. hyphal tubulin is encoded mainly by the essential genes tuba and bena. tubc is expressed during conidiation and tubb is required for the sexual cycle. promoter swappin ...200414998525
aspergillus nidulans as a model system to characterize the dna damage response in eukaryotes.interest in dna repair in aspergillus nidulans had mainly grown out of studies of three different biological processes, namely mitotic recombination, inducible responses to detrimental environmental changes, and genetic control of the cell cycle. ron morris started the investigation of the genetic control of the cell cycle by screening hundreds of cell cycle temperature sensitive aspergillus mutants. the sequencing and innovative analysis of these genes revealed not only several components of th ...200414998526
mate transposable elements in aspergillus nidulans: evidence of repeat-induced point mutation.the sequences of five mate transposable elements were retrieved from the aspergillus nidulans genome sequence. these elements are 6.1 kb in length and are characterized by 9-10 bp target site duplications, paired approximately 40 bp palindromes close to each end, and in the unmutated elements, 57 clustered spe-motifs (rwctagwy) scattered through their length. short open reading frames have no known homology. two of the mate elements have numerous c --> t transitions on both dna strands relative ...200414761791
nek8, a nima family kinase member, is overexpressed in primary human breast tumors.the family of human nek (nima related kinase) kinases currently contains 11 members. we have identified nek8 as a new member of the nek kinase family. for many of the nek family members, primary tumor expression data and function have been limited. however, all of the nek family proteins share considerable homology with the never in mitosis, gene a (nima) kinase from the filamentous fungus aspergillus nidulans. nima, as well as its most closely related human ortholog, nek2, are required for g(2) ...200415019993
a paradoxical mutant gata factor.the niia (nitrite reductase) and niad (nitrate reductase) genes of aspergillus nidulans are subject to both induction by nitrate and repression by ammonium or glutamine. the intergenic region between these genes functions as a bidirectional promoter. in this region, nucleosomes are positioned under nonexpression conditions. on nitrate induction under derepressing conditions, total loss of positioning occurs. this is independent of transcription and of the nira-specific transcription factor but a ...200415075269
dual-color imaging of nuclear division and mitotic spindle elongation in live cells of aspergillus nidulans.we have developed a dual-color imaging system based on cyan fluorescent protein-labeled histone h2a and green fluorescent protein-labeled alpha tubulin to visualize dna and spindles simultaneously in the same living cell of aspergillus nidulans. this system allows new details of mitosis and nuclear movement to be revealed.200415075284
biosynthesis and uptake of siderophores is controlled by the pacc-mediated ambient-ph regulatory system in aspergillus nidulans.biosynthesis and uptake of siderophores in aspergillus nidulans are regulated not only by iron availability but also by ambient ph: expression of this high-affinity iron uptake system is elevated by an increase in the ambient ph. mediation of this regulation by the transcriptional regulator pacc has been confirmed via acidity- and alkalinity-mimicking mutants.200415075286
structure of the 'open' form of aspergillus nidulans 3-dehydroquinate synthase at 1.7 a resolution from crystals grown following enzyme turnover.crystallization of aspergillus nidulans 3-dehydroquinate synthase (dhqs), following turnover of the enzyme by addition of the substrate dahp, gave a new crystal form (form j). although the crystals have dimensions of only 50 x 20 x 5 micro m, they are well ordered, diffracting to 1.7 a. the space group is c222(1), with unit-cell parameters a = 90.0, b = 103.7, c = 177.4 a. structure determination and refinement to r = 0.19 (r(free) = 0.25) shows the dhqs is in the 'open' form with the substrate ...200415103156
ren1 is required for development of microconidia and macroconidia, but not of chlamydospores, in the plant pathogenic fungus fusarium oxysporum.the filamentous fungus fusarium oxysporum is a soil-borne facultative parasite that causes economically important losses in a wide variety of crops. f. oxysporum exhibits filamentous growth on agar media and undergoes asexual development producing three kinds of spores: microconidia, macroconidia, and chlamydospores. ellipsoidal microconidia and falcate macroconidia are formed from phialides by basipetal division; globose chlamydospores with thick walls are formed acrogenously from hyphae or by ...200415020411
ethylene modulates development and toxin biosynthesis in aspergillus possibly via an ethylene sensor-mediated signaling pathway.ethylene, a biologically active natural compound, inhibited aflatoxin accumulation by aspergillus parasiticus on a solid growth medium in a dose-dependent manner at concentrations of 0.1 to 150 ppm. the activity of the nor-1 promoter (an early aflatoxin gene) was reduced to nondetectable levels by similar quantities of ethylene, suggesting that the inhibitory effect on toxin synthesis occurred, at least in part, at the level of transcription. the inhibitory effect of ethylene on aflatoxin accumu ...200415035355
candida albicans rim13p, a protease required for rim101p processing at acidic and alkaline phs.candida albicans is an important commensal of mucosal surfaces that is also an opportunistic pathogen. this organism colonizes a wide range of host sites that differ in ph; thus, it must respond appropriately to this environmental stress to survive. the ability to respond to neutral-to-alkaline phs is governed in part by the rim101 signal transduction pathway. here we describe the analysis of c. albicans rim13p, a homolog of the rim13p/palb calpain-like protease member of the rim101/pacc pathway ...200415189995
successful elimination of an invasive aspergillus nidulans lung infection by voriconazole after failure of a combination of caspofungin and liposomal amphotericin b in a boy with chronic granulomatous disease.chronic granulomatous disease is an inherited defect in host defense mechanisms mainly affecting neutrophil function. pulmonary infection with aspergillus nidulans in a child with chronic granulomatous disease could not be eliminated by a combination of caspofungin and liposomal amphotericin b. voriconazole was successful in clearing the infection.200415194848
transcription of purine transporter genes is activated during the isotropic growth phase of aspergillus nidulans conidia.aspergillus nidulans possesses three well-characterized purine transporters encoded by the genes uapa, uapc and azga. expression of these genes in mycelium is induced by purines and repressed by ammonium or glutamine through the action of the pathway-specific uay regulator and the general gata factor area respectively. here, we describe the regulation of expression of purine transporters during conidiospore germination and the onset of mycelium development. in resting conidiospores, mrna steady- ...200415049821
a basic-region helix-loop-helix protein-encoding gene (devr) involved in the development of aspergillus nidulans.basic-region helix-loop-helix (bhlh) proteins form an interesting class of eukaryotic transcription factors often involved in developmental processes. here, a so far unknown bhlh protein-encoding gene of the filamentous ascomycete aspergillus nidulans was isolated and designated devr for regulator of development. deletion of devr revealed that the gene is non-essential for vegetative growth. however, the deletion mutant produced wrinkled colonies, a yellow pigment and did not form conidia on min ...200415049823
negative subtraction hybridization: an efficient method to isolate large numbers of condition-specific cdnas.the construction of cdna libraries is a useful tool to understand gene expression in organisms under different conditions, but random sequencing of unbiased cdna collections is laborious and can give rise to redundant est collections. we aimed to isolate cdnas of messages induced by switching aspergillus nidulans from growth on glucose to growth on selected polysaccharides. approximately 4,700 contigs from 12,320 ests were already available from a cdna library representing transcripts isolated f ...200415050035
two delta9-stearic acid desaturases are required for aspergillus nidulans growth and development.unsaturated fatty acids are important constituents of all cell membranes and are required for normal growth. in the filamentous fungus aspergillus nidulans, unsaturated fatty acids and their derivatives also influence asexual (conidial) and sexual (ascospore) sporulation processes. to investigate the relationship between fatty acid metabolism and fungal development, we disrupted the a. nidulans sdea and sdeb genes, both encoding delta9-stearic acid desaturases responsible for the conversion of p ...200415050539
deletion of the aspergillus fumigatus lysine biosynthesis gene lysf encoding homoaconitase leads to attenuated virulence in a low-dose mouse infection model of invasive aspergillosis.aspergillus fumigatus is an important pathogen of the immunocompromised host, causing pneumonia and invasive disseminated disease with high mortality. in order to determine the importance of lysine biosynthesis for growth and pathogenicity, the a. fumigatus lysf gene, encoding a homologue of the a. nidulans homoaconitase lysf, was cloned and characterized. cosmid cosgtm encoding lysf complemented a lysf mutant of aspergillus nidulans. a. fumigatus lysf was deleted, resulting in a lysine-auxotrop ...200415052376
ph control of the production of recombinant glucose oxidase in aspergillus nidulans.recombinant aspergillus nidulans sval040, capable of synthesizing and secreting glucose oxidase derived from aspergillus niger was used to study the influence of ph and carbon source on enzyme production.200415239699
biosynthesis of poly(3-hydroxybutyrate- co-3-hydroxyalkanoates) by metabolically engineered escherichia coli strains.biosynthesis of polyhydroxyalkanoates (phas) consisting of 3-hydroxy-alkanoates (3has) of 4 to 10 carbon atoms was examined in metabolically engineered escherichia coli strains. when the fada and/or fadb mutant e. coli strains harboring the plasmid containing the pseudomonas sp. 61-3 phac2 gene and the ralstonia eutropha phaab genes were cultured in luria-bertani (lb) medium supplemented with 2 g/l of sodium decanoate, all the recombinant e. coli strains synthesized phas consisting of c4, c6, c8 ...200415054261
in vivo levels of s-adenosylmethionine modulate c:g to t:a mutations associated with repeat-induced point mutation in neurospora crassa.in neurospora crassa, the mutagenic process termed repeat-induced point mutation (rip) inactivates duplicated dna sequences during the sexual cycle by the introduction of c:g to t:a transition mutations. in this work, we have used a collection of n. crassa strains exhibiting a wide range of cellular levels of s-adenosylmethionine (adomet), the universal donor of methyl groups, to explore whether frequencies of rip are dependent on the cellular levels of this metabolite. mutant strains met-7 and ...200415063139
physiological and morphological changes in autolyzing aspergillus nidulans cultures.physiological and morphological changes in carbon-limited autolyzing cultures of aspergillus nidulans were described. the carbon starvation arrested conidiation while the formation of filamentous and "yeast-like" hyphal fragments with profoundly altered metabolism enabled the fungus to survive the nutritional stress. the morphological and physiological stress responses, which maintained the cellular integrity of surviving hyphal fragments at the expense of autolyzing cells, were highly concerted ...200415259768
blockage of methylcitrate cycle inhibits polyketide production in aspergillus nidulans.aspergillus nidulans produces the polyketide toxin sterigmatocystin (st) of which the biosynthetic and pathway specific regulatory genes compose a stc gene cluster. a previous mutagenesis screen identified 23 mutants defective in production of st. five mutants constitute a single locus. genetic complementation and sequencing analysis revealed the mutant locus to be mcsa encoding methylcitrate synthase that converts propionyl-coa to methylcitrate. feeding downstream products of methylcitrate synt ...200415066039
development of a system for integrative and stable transformation of the zygomycete rhizopus oryzae by agrobacterium-mediated dna transfer.two transformation systems, based on the use of cacl(2)/peg and agrobacterium tumefaciens, respectively, were developed for the zygomycete rhizopus oryzae. irrespective of the selection marker used, a pyr4 marker derived from r. niveus or a dominant amds(+) marker from aspergillus nidulans, and irrespective of the configuration of the transforming dna (linear or circular), the transformants obtained with the cacl(2)/peg transformation method were found to carry multiple copies of tandemly linked ...200415067540
screening for microtubule-disrupting antifungal agents by using a mitotic-arrest mutant of aspergillus nidulans and novel action of phenylalanine derivatives accompanying tubulin loss.the microtubule, which is one of the major targets of anthelmintics, anticancer drugs, and fungicides, is composed mainly of alpha- and beta-tubulins. we focused on a unique characteristic of an aspergillus nidulans bena33 mutant to screen for microtubule-disrupting antifungal agents. this mutant, which has a beta-tubulin with a mutation of a single amino acid, undergoes mitotic arrest due to the formation of hyperstable microtubules at 37 degrees c. the heat sensitivity of the mutant is remedie ...200415105129
vea is required for toxin and sclerotial production in aspergillus parasiticus.it was long been noted that secondary metabolism is associated with fungal development. in aspergillus nidulans, conidiation and mycotoxin production are linked by a g protein signaling pathway. also in a. nidulans, cleistothecial development and mycotoxin production are controlled by a gene called vea. here we report the characterization of a vea ortholog in the aflatoxin-producing fungus a. parasiticus. cleistothecia are not produced by aspergillus parasiticus; instead, this fungus produces sp ...200415294809
identification and characterization of a nitrate transporter gene in neurospora crassa.the neurospora crassa genome database was searched for sequence similarity to crna, a nitrate transporter in aspergillus nidulans. a 3.9-kb fragment (contig 3.416, subsequence 183190-187090) was cloned by pcr. the gene coding for this nitrate transporter was termed nit-10. the nit-10 gene specifies a predicted polypeptide containing 541 amino acids with a molecular mass of 57 kda. in contrast to crna, which is clustered together with niad, encoding nitrate reductase, and niia, encoding nitrite r ...200415068336
establishment of mrfp1 as a fluorescent marker in aspergillus nidulans and construction of expression vectors for high-throughput protein tagging using recombination in vitro (gateway).the advent of fluorescent proteins as vital dyes had a major impact in many research fields. different green fluorescent protein (gfp) variants were established in prokaryotic and eukaryotic organisms within the past 10 years, and other fluorescent proteins were discovered and applied. we expressed the discosoma red fluorescent protein, dsred (t4), the improved monomeric red fluorescent protein (mrfp1) and the blue fluorescent protein (bfp) in the filamentous fungus aspergillus nidulans. whereas ...200415071756
differential expression of the chitin synthase genes of aspergillus nidulans, chsa, chsb, and chsc, in response to developmental status and environmental factors.to understand the role of the chitin synthase genes of aspergillus nidulans, we analyzed the expression of chsa, chsb, and chsc both by northern blotting and by a vital reporter system with sgfp encoding a modified version of green fluorescent protein, sgfp. chsa was expressed specifically during asexual differentiation, but not during either vegetative growth or sexual differentiation. the expression of chsb was ubiquitous throughout the fungal body and relatively independent of the change in d ...200415121085
nitrate reductase activity is required for nitrate uptake into fungal but not plant cells.the ability to transport net nitrate was conferred upon transformant cells of the non-nitrate-assimilating yeast pichia pastoris after the introduction of two genes, one encoding nitrate reductase and the other nitrate transport. it was observed that cells of this lower eukaryote transformed with the nitrate transporter gene alone failed to display net nitrate transport despite having the ability to produce the protein. in addition, loss-of-function nitrate reductase mutants isolated from severa ...200415123642
altering a gene involved in nuclear distribution increases the repeat-induced point mutation process in the fungus podospora anserina.repeat-induced point mutation (rip) is a homology-dependent gene-silencing mechanism that introduces c:g-to-t:a transitions in duplicated dna segments. cis-duplicated sequences can also be affected by another mechanism called premeiotic recombination (pr). both are active over the sexual cycle of some filamentous fungi, e.g., neurospora crassa and podospora anserina. during the sexual cycle, several developmental steps require precise nuclear movement and positioning, but connections between rip ...200415166143
prp8 intein in fungal pathogens: target for potential antifungal drugs.inteins are self-splicing intervening sequences in proteins, and inteins of pathogenic organisms can be attractive drug targets. here, we report an intein in important fungal pathogens including aspergillus fumigatus, aspergillus nidulans, histoplasma capsulatum, and different serotypes of cryptococcus neoformans. this intein is inside the extremely conserved and functionally essential prp8 protein, and it varies in size from 170 aa in c. neoformans to 819 aa in a. fumigatus, which is caused by ...200415304322
streptomyces lividans and brevibacterium lactofermentum as heterologous hosts for the production of x22 xylanase from aspergillus nidulans.the aspergillus nidulans gene xlna coding for the fungal xylanase x22 has been cloned and expressed in two heterologous bacterial hosts: streptomyces lividans and brevibacterium lactofermentum. streptomyces strains yielded 10 units/ml of xylanase when the protein was produced with its own signal peptide, and 19 units/ml when its signal peptide was replaced by the one for xylanase xys1 from streptomyces halstedii. b. lactofermentum was also able to produce xylanase x22, affording 6 units/ml upon ...200415168093
histone methyltransferases in aspergillus nidulans: evidence for a novel enzyme with a unique substrate specificity.we have studied enzymes involved in histone arginine methylation in the filamentous fungus aspergillus nidulans. three distinct protein arginine methyltransferases (prmts) could be identified, which all exhibit intrinsic histone methyltransferase activity when expressed as glutathione s-transferase (gst) fusion proteins. two of these proteins, termed rmta (arginine methyltransferase a) and rmtc, reveal significant sequence homology to the well-characterized human proteins prmt1 and prmt5, respec ...200415311944
mesa, a novel fungal protein required for the stabilization of polarity axes in aspergillus nidulans.the aspergillus nidulans proteome possesses a single formin, sepa, which is required for actin ring formation at septation sites and also plays a role in polarized morphogenesis. previous observations imply that complex regulatory mechanisms control the function of sepa and ensure its correct localization within hyphal tip cells. to characterize these mechanisms, we undertook a screen for mutations that enhance sepa defects. of the mutants recovered, mesa1 causes the most dramatic defect in pola ...200415155805
pina is essential for growth and positively influences nima function in aspergillus nidulans.the phospho-ser/thr-directed prolyl-isomerase pin1 was originally identified in vertebrate systems as a negative regulator of nima, a ser/thr protein kinase that regulates the g(2)/m transition in aspergillus nidulans. here we explore the physiological roles of the pin1 orthologue, pina, in a. nidulans and evaluate the relevance of the interaction of pina with nima in this fungus. we find pina to be an essential gene in a. nidulans. in addition, when pina levels are reduced 50-fold the cells gro ...200415178679
the dual nature of the wheat xylanase protein inhibitor xip-i: structural basis for the inhibition of family 10 and family 11 xylanases.the xylanase inhibitor protein i (xip-i) from wheat triticum aestivum is the prototype of a novel class of cereal protein inhibitors that inhibit fungal xylanases belonging to glycoside hydrolase families 10 (gh10) and 11 (gh11). the crystal structures of xip-i in complex with aspergillus nidulans (gh10) and penicillium funiculosum (gh11) xylanases have been solved at 1.7 and 2.5 a resolution, respectively. the inhibition strategy is novel because xip-i possesses two independent enzyme-binding s ...200415181003
identification and characterization of a novel delta12-fatty acid desaturase gene from rhizopus arrhizus.based on the sequence information of delta12-fatty acid desaturase genes (from mucor circinelloides, mortierella alpina, mucor rouxii and aspergillus nidulans), which were involved in the conversion from c18:1 to c18:2, a cdna sequence putatively encoding a delta12-fatty acid desaturase was isolated from rhizopus arrhizus using the combination of reverse transcription-polymerase chain reaction (rt-pcr) and rapid amplification of cdna ends (race) methods. sequence analysis indicated that it had a ...200415327973
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