TitleAbstractYear(sorted descending)
patterns of nucleosomal organization in the alc regulon of aspergillus nidulans: roles of the alcr transcriptional activator and the crea global repressor.we have studied the chromatin organization of three promoters of the alc regulon of aspergillus nidulans. no positioned nucleosomes are seen in the alda (aldehyde dehydrogenase) promoter under any physiological condition tested by us. in the alca (alcohol dehydrogenase i) and alcr (coding for the pathway-specific transcription factor) promoters, a pattern of positioned nucleosomes is seen under non-induced and non-induced repressed conditions. while each of these promoters shows a specific patte ...200515813742
protein production and secretion in an aspergillus nidulans mutant impaired in glycosylation.o-glycosylation has been considered a limiting factor in protein secretion in filamentous fungi. overexpression of the yeast dpm1 gene encoding dolichylphosphate mannose synthase (dpms) in an aspergillus nidulans mutant (bwb26a) deficient in o-glycosylation caused an increase in the number of secretory vesicles and changes in protein secretion. however, the secretory proteins, primarily o-mannosylated glucoamylase and n-glycosylated invertase, were mainly trapped in the periplasmic space. differ ...200515827617
tobacco smoke as inducer for gas phase-controlled transgene expression in mammalian cells and mice.capitalizing on components evolved to metabolize ethanol in aspergillus nidulans, we previously designed the first molecular gas-gene expression interface using gaseous acetaldehyde as the major inducer. this fungus-derived acetaldehyde-inducible gene regulation (air) system operated perfectly and enabled precise and reversible transgene expression dosing in a variety of mammalian cells. we now validate the use of mainstream cigarette smoke typically containing acetaldehyde at regulation-effecti ...200515841470
discovery of a novel superfamily of type iii polyketide synthases in aspergillus oryzae.identification of genes encoding type iii polyketide synthase (pks) superfamily members in the industrially useful filamentous fungus, aspergillus oryzae, revealed that their distribution is not specific to plants or bacteria. among other aspergilli (aspergillus nidulans and aspergillus fumigatus), a. oryzae was unique in possessing four chalcone synthase (chs)-like genes (csya, csyb, csyc, and csyd). expression of csya, csyb, and csyd genes was confirmed by rt-pcr. comparative genome analyses r ...200515845386
application of molecular modeling to analysis of inhibition of kinesin motor proteins of the bimc subfamily by monastrol and related compounds.application of molecular modeling approaches has potential to contribute to rational drug design. these approaches may be especially useful when attempting to elucidate the structural features associated with novel drug targets. in this study, molecular docking and molecular dynamics were applied to studies of inhibition of the human motor protein denoted hseg5 and other homologues in the bimc subfamily. these proteins are essential for mitosis, so compounds that inhibit their activity may have ...200517191952
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
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
loss of heterozygosity by mitotic recombination in diploid strain of aspergillus nidulans in response to castor oil plant detergent.somatic recombination in heterozygous diploid cells may be a promotional agent of neoplasms by inducing homozygosity of defective genes. tumor suppressor genes may in this way be completely suppressed in recombinant cells. in this work, the genotoxic effects of detergent derived from the castor oil plant (ricinus communis) in heterozygous diploid cells of aspergillus nidulans are evaluated. previous studies have evaluated the application of this substance in endodontic treatments as an irrigatin ...200415744430
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
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
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
penicillium chrysogenum glucose oxidase -- a study on its antifungal effects.purification and characterization of the high molecular mass candida albicans-killing protein secreted by penicillium chrysogenum.200415546411
endogenous lipogenic regulators of spore balance in aspergillus nidulans.the ability of fungi to produce both meiospores and mitospores has provided adaptive advantages in survival and dispersal of these organisms. here we provide evidence of an endogenous mechanism that balances meiospore and mitospore production in the model filamentous fungus aspergillus nidulans. we have discovered a putative dioxygenase, ppoc, that functions in association with a previously characterized dioxygenase, ppoa, to integrate fatty acid derived oxylipin and spore production. in contras ...200415590815
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
potential link between the nima mitotic kinase and nuclear membrane fission during mitotic exit in aspergillus nidulans.we have isolated tinc as a nima-interacting protein by using the yeast two-hybrid system and have confirmed that tinc interacts with nima in aspergillus nidulans. the tinc-nima interaction is stabilized in the absence of phosphatase inhibitors and in the presence of kinase-inactive nima, suggesting that the interaction is enhanced when nima is not fully activated. tinc is a cytoplasmic protein. tinc homologues and a tinc-like protein (a. nidulans hetc) are conserved in other filamentous fungi. n ...200415590818
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
alcohol-mediated haemolysis in yeast.although yeast are generally non-haemolytic, we have found that addition of alcohol vapour confers haemolytic properties on many strains of yeast and other fungi. we have called this phenomenon 'microbial alcohol-conferred haemolysis' (mach). mach is species- and strain-specific: whereas all six candida tropicalis strains tested were haemolytic in the presence of ethanol, none among 10 c. glabrata strains tested exhibited this phenomenon. among 27 c. albicans strains and 11 saccharomyces cerevis ...200415565638
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
mitochondrial beta-oxidation in aspergillus nidulans.beta-oxidation (beta-ox) occurs exclusively in the peroxisomes of saccharomyces cerevisiae and other yeasts, leading to the supposition that fungi lack mitochondrial beta-ox. here we present unequivocal evidence that the filamentous fungus aspergillus nidulans houses both peroxisomal and mitochondrial beta-ox. while growth of a peroxisomal beta-ox disruption mutant (deltafoxa) was eliminated on a very long-chain fatty acid (c(22:1)), growth was only partially impeded on a long-chain fatty acid ( ...200415554960
partial nuclear pore complex disassembly during closed mitosis in aspergillus nidulans.many organisms undergo closed mitosis and locate tubulin and mitotic kinases to nuclei only during mitosis. how this is regulated is unknown. interestingly, the nima kinase of aspergillus nidulans interacts with two nuclear pore complex (npc) proteins and nima is required for mitotic localization of the cdk1 kinase to nuclei. therefore, we wished to define the mechanism by which the npc is regulated during a. nidulans' closed mitosis.200415556859
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
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
acfkh1, a novel member of the forkhead family, associates with the rfx transcription factor cpcr1 in the cephalosporin c-producing fungus acremonium the filamentous fungus acremonium chrysogenum, a complex regulatory network of transcription factors controls the expression of at least seven cephalosporin c biosynthesis genes. the rfx transcription factor cpcr1 binds to regulatory sequences in the promoter region of cephalosporin c biosynthesis genes, and is involved in the transcriptional regulation of the pcbc gene which encodes isopenicillin n synthase. in this study, we used cpcr1 in a yeast two-hybrid screen to identify potential prot ...200415527986
the fungal stre-element-binding protein seb1 is involved but not essential for glycerol dehydrogenase (gld1) gene expression and glycerol accumulation in trichoderma atroviride during osmotic stress.fungi counteract extracellular osmotic pressure by producing intracellular polyols to prevent loss of water. in yeast osmotic signaling involves a map-kinase pathway culminating at the stre-binding transcription factors msn2/4. we investigated the role of a putative stre-binding orthologue of trichoderma atroviride, seb1, in osmotic stress signaling. t. atroviride, subjected to osmotic stress (10% glucose or glycerol, 1m kcl or nacl), responds by raising its intracellular glycerol level. in cont ...200415531216
modulation of the ligand binding properties of the transcription repressor nmra by gata-containing dna and site-directed mutagenesis.nmra is a negative transcription-regulating protein that binds to the c-terminal region of the gata transcription-activating protein area. the proposed molecular mechanism of action for nmra is to inhibit area binding to its target promoters. in contrast to this proposal, we report that a c-terminal fragment of area can bind individually to gata-containing dna and nmra and that in the presence of a mixture of gata-containing dna and nmra, the area fragment binds preferentially to the gata-contai ...200415537757
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
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
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
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
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
tama interacts with leub, the homologue of saccharomyces cerevisiae leu3p, to regulate gdha expression in aspergillus nidulans.previous studies have shown that expression of the gdha gene, encoding nadp-linked glutamate dehydrogenase (nadp-gdh), in aspergillus nidulans is regulated by the major nitrogen regulatory protein area and its co-activator tama. we show here that loss of tama function has a more severe effect on the levels of gdha expression than loss of area function. using tama as the bait in a yeast two-hybrid screen, we have identified a second protein that interacts with tama. sequencing analysis and functi ...200415517391
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
combining transcriptome data with genomic and cdna sequence alignments to make confident functional assignments for aspergillus nidulans genes.whole genome sequencing of several filamentous ascomycetes is complete or in progress; these species, such as aspergillus nidulans, are relatives of saccharomyces cerevisiae. however, their genomes are much larger and their gene structure more complex, with genes often containing multiple introns. automated annotation programs can quickly identify open reading frames for hypothetical genes, many of which will be conserved across large evolutionary distances, but further information is required t ...200415449589
[rgs proteins (regulators of g protein signaling) and their roles in regulation of immune response].rgs proteins (regulators of g-protein signaling) comprise a protein family responsible for regulating g proteins. by enhancing the gtpase activity of the a subunit, they speed up the reconstruction of the heterotrimeric structure of g protein, thus inhibiting its signal transduction. sst2 protein in yeast saccharomyces cervisiae, flba in fungus aspergillus nidulans, and egl-10 in the nematode caenorhabditis elegans are the first native g regulators with gtpase activity (gaps:--gtpase-activating ...200415459549
comparison of ligand-induced conformational changes and domain closure mechanisms, between prokaryotic and eukaryotic dehydroquinate synthases.dehydroquinate synthase (dhqs) is a potential target for the development of novel broad-spectrum antimicrobial drugs, active against both prokaryotes and lower eukaryotes. structures have been reported for aspergillus nidulans dhqs (andhqs) in complexes with a range of ligands. analysis of these andhqs structures showed that a large-scale domain movement occurs during the normal catalytic cycle, with a complex series of structural elements propagating substrate binding-induced conformational cha ...200415465043
double-joint pcr: a pcr-based molecular tool for gene manipulations in filamentous fungi.gene replacement via homologous double crossover in filamentous fungi requires relatively long (preferentially >0.5 kb) flanking regions of the target gene. for this reason, gene replacement cassettes are usually constructed through multiple cloning steps. to facilitate gene function studies in filamentous fungi avoiding tedious cloning steps, we have developed a pcr-assisted dna assembly procedure and applied it to delete genes in filamentous fungi. while the principle of this procedure is esse ...200415465386
identification and complementation of abnormal hyphal branch mutants ahba1 and ahbb1 in aspergillus nidulans.branching generates new axes of polar growth in filamentous fungi and is critical for development, reproduction, and pathogenicity. to investigate branching we screened an aspergillus nidulans temperature-sensitive mutant collection for abnormal hyphal branch (ahb) mutants. we identified two mutants, ahba1, which showed reduced branching relative to wild type at restrictive temperature, and ahbb1, which showed increased branching relative to wild type at restrictive temperature. both mutants als ...200415465388
the aspergillus fumigatus cell wall is organized in domains that are remodelled during polarity establishment.aspergillus fumigatus is a life-threatening and increasingly frequent pathogen of the immunocompromised. like other filamentous fungi a. fumigatus grows in a highly polar manner, adding new cell wall to the apical region of hyphae. mabs were raised against isolated a. fumigatus cell walls. fifteen antibodies bound reproducibly to isolated cell walls in elisas and to the walls of intact cells in immunofluorescence experiments. surprisingly, individual mabs showed distinct patterns of localization ...200415470106
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
rapid production of gene replacement constructs and generation of a green fluorescent protein-tagged centromeric marker in aspergillus nidulans.a method to rapidly generate gene replacement constructs by fusion pcr is described for aspergillus nidulans. the utility of the approach is demonstrated by green fluorescent protein (gfp) tagging of a. nidulans ndc80 to visualize centromeres through the cell cycle. the methodology makes possible large-scale gfp tagging, promoter swapping, and deletion analysis of a. nidulans.200415470263
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
use of expressed sequence tag analysis and cdna microarrays of the filamentous fungus aspergillus nidulans.the use of microarrays in the analysis of gene expression is becoming widespread for many organisms, including yeast. however, although the genomes of a number of filamentous fungi have been fully or partially sequenced, microarray analysis is still in its infancy in these organisms. here, we describe the construction and validation of microarrays for the fungus aspergillus nidulans using pcr products from a 4092 est conidial germination library. an experiment was designed to validate these arra ...200414732266
novel effect of voriconazole on conidiation of aspergillus species.our previous studies of aspergillus fumigatus showed that colonies that grew in the presence of voriconazole (vcz) were characteristically white without pigmentation. we therefore investigated the effect of various triazoles on conidiation and pigmentation in four commonly isolated aspergillus species and the results were compared with those obtained for polyene and echinocandin classes of antifungal drugs. aspergillus cultures were grown on sabouraud dextrose agar containing subinhibitory conce ...200414732317
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
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
activation of caspase-like activity and poly (adp-ribose) polymerase degradation during sporulation in aspergillus nidulans.mycelium vacuolization, protein degradation, and as the final stage autolysis, often accompanies developmental changes in fungi and similarities between autolysis and apoptosis have previously been suggested. caspases are the key executors of apoptosis and in this study caspase-like activities were detected in protein extracts from aspergillus nidulans during sporulation. this was shown by hydrolysis of the fluorescent devd- and ietd-afc peptide substrates specific for caspase 3- and 8-like acti ...200414761796
chromatin rearrangements in the prnd-prnb bidirectional promoter: dependence on transcription factors.the prnd-prnb intergenic region regulates the divergent transcription of the genes encoding proline oxidase and the major proline transporter. eight nucleosomes are positioned in this region. upon induction, the positioning of these nucleosomes is lost. this process depends on the specific transcriptional activator prna but not on the general gata factor area. induction of prnb but not prnd can be elicited by amino acid starvation. a specific nucleosomal pattern in the prnb proximal region is as ...200414871945
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
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
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
insight into the genome of aspergillus fumigatus: analysis of a 922 kb region encompassing the nitrate assimilation gene cluster.aspergillus fumigatus is the most ubiquitous opportunistic filamentous fungal pathogen of human. as an initial step toward sequencing the entire genome of a. fumigatus, which is estimated to be approximately 30 mb in size, we have sequenced a 922 kb region, contained within 16 overlapping bacterial artificial chromosome (bac) clones. fifty-four percent of the dna is predicted to be coding with 341 putative protein coding genes. functional classification of the proteins showed the presence of a h ...200414998527
identification of a novel gene hbrb required for polarised growth in aspergillus nidulans.we have cloned a novel gene, hbrb, by complementation of a temperature sensitive hyperbranching (hbr) mutant of aspergillus nidulans. the mutant, hbrb3, exhibits hyperseptation and shows a marked increase in hyphal branching at the restrictive temperature. a genomic library incorporating the ama1 sequence, which confers autonomous replication on the plasmid, was used to clone the gene. co-ordinate loss of the complementing plasmid and wild type phenotype was shown. the 847 amino acid predicted p ...200414998529
a sensitive predictor for potential gpi lipid modification sites in fungal protein sequences and its application to genome-wide studies for aspergillus nidulans, candida albicans, neurospora crassa, saccharomyces cerevisiae and schizosaccharomyces pombe.the fungal transamidase complex that executes glycosylphosphatidylinositol (gpi) lipid anchoring of precursor proteins has overlapping but distinct sequence specificity compared with the animal system. therefore, a taxon-specific prediction tool for the recognition of the c-terminal signal in fungal sequences is necessary. we have collected a learning set of fungal precursor protein sequences from the literature and fungal proteomes. although the general four segment scheme of the recognition si ...200415003443
molecular cloning and functional characterization of avab, a gene encoding vam6p/vps39p-like protein in aspergillus 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
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
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
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
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
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
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
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 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
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
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
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
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
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
differential expression of the chitin synthase genes of aspergillus nidulans, chsa, chsb, and chsc, in response to developmental status and environmental 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
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
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
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
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
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
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
fungal metabolic model for type i 3-methylglutaconic aciduria.aspergillus nidulans catabolizes leu to acetyl-coa and acetoacetate through a pathway homologous to that used by humans. fungal hlya encodes a bifunctional polypeptide comprising the last two enzymes in this pathway, 3-methylglutaconyl-coa hydratase and 3-hydroxy-3-methylglutaryl-coa lyase. hlya transcription is specifically induced by leu. a delta hlya mutation removing the complete 3-methylglutaconyl-coa hydratase c-terminal domain prevents growth on leu but not on lactose or other amino acids ...200415181004
molecular characterization of protein o-mannosyltransferase and its involvement in cell-wall synthesis in aspergillus nidulans.protein o-glycosylation is essential for protein modification and plays important roles in eukaryotic cells. o-mannosylation of proteins occurs in the filamentous fungus aspergillus. the structure and function of the pmta gene, encoding protein o-d-mannosyltransferase, which is responsible for the initial o-mannosylation reaction in aspergillus nidulans, was characterized. disruption of the pmta gene resulted in the reduction of in vitro protein o-d-mannosyltransferase activity to 6 % of that of ...200415184583
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