Publications
Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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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 ... | 2004 | 15525405 |
the zn(ii)2cys6 putative aspergillus nidulans transcription factor repressor of sexual development inhibits sexual development under low-carbon conditions and in submersed culture. | here we have characterized the putative zn(ii)2cys6 transcription factor rosa from the filamentous fungus aspergillus nidulans. the rosa gene encodes a protein of 713 aa, which shares 38% sequence similarity to pro1 from sordaria macrospora. in contrast to pro1, which promotes the transition from protoperithecia to perithecia, rosa is a negative regulator of sexual development in a. nidulans. transcript levels of rosa were usually very low and were only transiently upregulated upon carbon starva ... | 2005 | 15520269 |
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 ... | 2004 | 15518351 |
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 ... | 2004 | 15517391 |
[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 ... | 2004 | 15515902 |
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 ... | 2004 | 15514053 |
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 ... | 2004 | 15505717 |
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 ... | 2004 | 15502819 |
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 ... | 2004 | 15487944 |
a functional screen identifies lateral transfer of beta-glucuronidase (gus) from bacteria to fungi. | lateral gene transfer (lgt) from prokaryotes to microbial eukaryotes is usually detected by chance through genome-sequencing projects. here, we explore a different, hypothesis-driven approach. we show that the fitness advantage associated with the transferred gene, typically invoked only in retrospect, can be used to design a functional screen capable of identifying postulated lgt cases. we hypothesized that beta-glucuronidase (gus) genes may be prone to lgt from bacteria to fungi (thought to la ... | 2005 | 15483318 |
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. | 2004 | 15470263 |
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 ... | 2004 | 15470237 |
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 ... | 2004 | 15470106 |
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 ... | 2004 | 15465388 |
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 ... | 2004 | 15465386 |
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 ... | 2004 | 15465043 |
[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 ... | 2004 | 15459549 |
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 ... | 2004 | 15449589 |
[pathogenic power of aspergillus nidulans under experimental conditions]. | 1950 | 15424397 | |
multi-copy suppression of an aspergillus nidulans mutant sensitive to camptothecin by a putative monocarboxylate transporter. | the mono carboxylate transporter (mct) is a family of membrane proteins from the major facilitator superfamily (mfs) of transporters. here, we report the first identified aspergillus nidulans mct homologue, amca. the amca gene was isolated by high copy number suppression of the hydroxyurea (hu) sensitivity of an a. nidulans camptothecin-sensitive mutant. expression of amca is increased when hyphae are grown in media containing acetate or pyruvate as single carbon source, and after exposure to se ... | 2004 | 15386109 |
unique biosynthesis of dehydroquinic acid? | a search of the genomic sequences of the thermophilic microorganisms aquifex aeolicus, archaeoglobus fulgidus, methanobacterium thermoautotrophicum, and methanococcus jannaschii for the first seven enzymes (arog, b, d, e, k, a, and c ) involved in the shikimic acid biosynthetic pathway reveal two key enzymes are missing. the first enzyme in the pathway, 3-deoxy-d-arabino-heptulosonic acid 7-phosphate synthase (arog) and the second enzyme in the pathway, 5-dehydroquinic acid synthase (arob) are " ... | 2004 | 15381397 |
inhibitors of types i and ii dehydroquinase. | inhibitors of varying potency have been developed for types i and ii 3-dehydroquinate dehydratase (dehydroquinase), enzymes from the shikimate and quinate pathways that catalyse the dehydration of dehydroquinate to dehydroshikimate. these inhibitors have resulted from enzyme mechanistic studies and from the direct search for enzyme inhibitors with herbicidal, fungicidal or antimicrobial potential. this review discusses the design of the various inhibitors that have been produced so far and some ... | 2004 | 15379642 |
functional analysis of the homoserine o-acetyltransferase gene and its identification as a selectable marker in gibberella zeae. | we used restriction enzyme-mediated integration (remi) to identify a methionine auxotrophic mutant of gibberella zeae, an important cereal pathogen. in addition to its methionine requirement, the g. zeae remi mutant designated z43r3912 showed pleiotropic phenotypes, including reduced virulence on host plants and lack of sexual development. outcrossing of z43r3912 with a mat1-1 deletion strain confirmed that the mutation of z43r3912 was tagged with the hygromycin b resistance marker. the vector i ... | 2004 | 15378266 |
efficient gene disruption in the koji-mold aspergillus sojae using a novel variation of the positive-negative method. | when no phenotypic screen is available, gene disruption in the koji-mold aspergillus sojae is a time-consuming process, owing to the low frequency of homologous recombination. to achieve efficient gene disruption in the koji-mold, we developed a novel positive-negative selection method to enrich for homologous recombinants. the pyrg gene from a. sojae was used as a positive selection marker for transformants, and the olic31 gene of a. nidulans, which codes for a mutant form of subunit 9 of the f ... | 2004 | 15375695 |
the role of thiol species in the hypertolerance of aspergillus sp. p37 to arsenic. | aspergillus sp. p37 is an arsenate-hypertolerant fungus isolated from a river in spain with a long history of contamination with metals. this strain is able to grow in the presence of 0.2 m arsenate, i.e. 20-fold higher than the reference strain, aspergillus nidulans ts1. although aspergillus sp. p37 reduces as(v) to as(iii), which is slowly pumped out of the cell, the measured efflux of oxyanions is insufficient to explain the high tolerance levels of this strain. to gain an insight into this p ... | 2004 | 15364940 |
characterization of the aspergillus parasiticus delta12-desaturase gene: a role for lipid metabolism in the aspergillus-seed interaction. | in the mycotoxigenic oilseed pathogens aspergillus flavus and aspergillus parasiticus and the model filamentous fungus aspergillus nidulans, unsaturated fatty acids and their derivatives act as important developmental signals that affect asexual conidiospore, sexual ascospore and/or sclerotial development. to dissect the relationship between lipid metabolism and fungal development, an a. parasiticus delta(12)-desaturase mutant that was unable to convert oleic acid to linoleic acid and was thus i ... | 2004 | 15347747 |
the aspergillus nidulans npka gene encodes a cdc2-related kinase that genetically interacts with the uvsbatr kinase. | the dna damage response is a protective mechanism that ensures the maintenance of genomic integrity. we have used aspergillus nidulans as a model system to characterize the dna damage response caused by the antitopoisomerase i drug, camptothecin. we report the molecular characterization of a p34cdc2-related gene, npka, from a. nidulans. the npka gene is transcriptionally induced by camptothecin and other dna-damaging agents, and its induction in the presence of camptothecin is dependent on the u ... | 2004 | 15342504 |
the gpra and gprb genes encode putative g protein-coupled receptors required for self-fertilization in aspergillus nidulans. | the filamentous fungus aspergillus nidulans possesses both asexual and sexual reproductive cycles. sexual fruiting bodies (cleistothecia) can be formed in both homothallic (self) and heterothallic (outcross) conditions. in this study, we characterized two genes, gpra and gprb, that are predicted to encode putative g protein-coupled receptors (gpcrs) similar to fungal pheromone receptors. deletion (delta) of gpra or gprb resulted in the production of a few small cleistothecia carrying a reduced n ... | 2004 | 15341643 |
terbinafine resistance mediated by salicylate 1-monooxygenase in aspergillus nidulans. | resistance to antifungal agents is a recurring and growing problem among patients with systemic fungal infections. uv-induced aspergillus nidulans mutants resistant to terbinafine have been identified, and we report here the characterization of one such gene. a sib-selected, 6.6-kb genomic dna fragment encodes a salicylate 1-monooxygenase (sala), and a fatty acid synthase subunit (fasc) confers terbinafine resistance upon transformation of a sensitive strain. subfragments carrying sala but not f ... | 2004 | 15328121 |
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 ... | 2004 | 15327973 |
a single subunit of a heterotrimeric ccaat-binding complex carries a nuclear localization signal: piggy back transport of the pre-assembled complex to the nucleus. | an unresolved question concerns the nuclear localization of the heterotrimeric ccaat-binding complex, which is evolutionarily conserved in eukaryotic organisms including fungi, plants and mammals. all three subunits are necessary for dna binding. in the filamentous fungus aspergillus nidulans the corresponding complex was designated ancf (a.nidulans ccaat-binding factor). ancf consists of the hapb, hapc and hape subunits. here, by using various green fluorescent protein constructs, a nuclear loc ... | 2004 | 15327951 |
unprecedented mechanism of chain length determination in fungal aromatic polyketide synthases. | fungal aromatic polyketides show remarkable structural diversity fundamentally derived from variations in chain length and cyclization pattern. their basic skeletons are synthesized by multifunctional iterative type i polyketide synthases (pkss). recently, we have found that the c-terminal thioesterase (te)-like domain of aspergillus nidulans wa catalyzes claisen-type cyclization to form the b-ring of naphthopyrone ywa1. here we report the unprecedented mechanism of chain length determination by ... | 2004 | 15324811 |
an appropriate increase in the transcription of aspergillus nidulans uvsc improved gene targeting efficiency. | gene targeting to knock out the activity of specific genes has become important due to recent progress in genomics research. but this technique is still unavailable for many organisms, including economically important microorganisms, due to the high background of ectopic integration during genetic transformation. strategies to improve targeting efficiency have included manipulating the expression of genes that are involved in homologous recombination. in this study, transcription of aspergillus ... | 2004 | 15322347 |
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 ... | 2004 | 15311944 |
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 ... | 2004 | 15304762 |
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 ... | 2004 | 15304761 |
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 ... | 2004 | 15304322 |
chpa, a cysteine- and histidine-rich-domain-containing protein, contributes to maintenance of the diploid state in aspergillus nidulans. | the alternation of eukaryotic life cycles between haploid and diploid phases is crucial for maintaining genetic diversity. in some organisms, the growth and development of haploid and diploid phases are nearly identical, and one might suppose that all genes required for one phase are likely to be critical for the other phase. here, we show that targeted disruption of the chpa (cysteine- and histidine-rich-domain- [chord]-containing protein a) gene in haploid aspergillus nidulans strains gives ri ... | 2004 | 15302831 |
effect of ph on the stability of pleurotus eryngii versatile peroxidase during heterologous production in emericella nidulans. | complementary dna (cdna) encoding the new versatile peroxidase from the ligninolytic basidiomycete pleurotus eryngii has been expressed in the ascomycete emericella nidulans. in recombinant e. nidulans cultures, the ph reached values as high as 8.3, correlating with a sharp decrease in peroxidase activity. peroxidase was rapidly inactivated at alkaline ph, but was comparatively stable at acidic ph. the peroxidase inactivation in alkaline buffer could be reversed by adding ca(2+) and lowering the ... | 2004 | 15300480 |
isocitrate lyase from aspergillus nidulans: crystallization and x-ray analysis of a glyoxylate cycle enzyme. | isocitrate lyase (icl) from the filamentous fungus aspergillus nidulans catalyzes the first committed step of the carbon-conserving glyoxylate bypass. this enzyme has been crystallized by the hanging-drop method of vapour diffusion using polyethylene glycol 2000 as the precipitant. diffraction patterns show that the crystals diffract to beyond 2.5 a and are probably in space group p4(2)2(1)2 with unit-cell dimensions of a = b = 91.9 and c = 152.7 a, with one molecule in the asymmetric unit. the ... | 1997 | 15299923 |
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 ... | 2004 | 15297933 |
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 ... | 2004 | 15297489 |
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 ... | 2004 | 15294809 |
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 ... | 2004 | 15283239 |
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 ... | 2004 | 15280244 |
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 ... | 2004 | 15265042 |
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 ... | 2004 | 15259768 |
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 ... | 2004 | 15255903 |
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 ... | 2004 | 15247298 |
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. | 2004 | 15239699 |
airborne fungi in industrial environments--potential agents of respiratory diseases. | investigations on airborne fungi in a poultry house, a swinery, a feed preparing and storing house, a grain mill, a wooden panel producing factory, and organic waste recycling facilities have been carried out in lithuania. low concentrations of fungal spores were detected in the wooden panel producing factory, the swinery, the feed preparing and storing house, and the poultry house; moderate concentrations were found in the organic waste recycling facilities; high concentrations were revealed at ... | 2004 | 15236494 |
agrobacterium tumefaciens-mediated genetic transformation of the entomopathogenic fungus beauveria bassiana. | agrobacterium tumefaciens-mediated transformation (agro-transformation) was successfully applied to the entomogenous fungus beauveria bassiana. conidia of b. bassiana were transformed to hygromycin b resistance using the hph gene of escherichia coli as the selective trait, under the control of a heterologous fungal promoter and the aspergillus nidulans trpc terminator. the efficiency of transformation was up to 28 and 96 transformants per 10(4) and 10(5) target conidia, respectively, using three ... | 2004 | 15234517 |
tangled nudels? | 2004 | 15232582 | |
regulators of g-protein signalling in aspergillus nidulans: rgsa downregulates stress response and stimulates asexual sporulation through attenuation of ganb (galpha) signalling. | regulators of g-protein signalling play a crucial role in controlling the degree of heterotrimeric g-protein signalling. in addition to the previously studied flba, we have identified three genes (rgsa, rgsb and rgsc) encoding putative rgs proteins in the genome of aspergillus nidulans. characterization of the rgsa gene revealed that rgsa downregulates pigment production and conidial germination, but stimulates asexual sporulation (conidiation). deletion of rgsa (deltargsa) resulted in reduced c ... | 2004 | 15228532 |
a nudel-dependent mechanism of neurofilament assembly regulates the integrity of cns neurons. | the cytoskeleton controls the architecture and survival of central nervous system (cns) neurons by maintaining the stability of axons and dendrites. although neurofilaments (nfs) constitute the main cytoskeletal network in these structures, the mechanism that underlies subunit incorporation into filaments remains a mystery. here we report that nudel, a mammalian homologue of the aspergillus nidulans nuclear distribution molecule nude, is important for nf assembly, transport and neuronal integrit ... | 2004 | 15208636 |
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. | 2004 | 15194848 |
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 ... | 2004 | 15189995 |
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 ... | 2004 | 15189985 |
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 ... | 2004 | 15184583 |
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 ... | 2004 | 15181004 |
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 ... | 2004 | 15181003 |
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 ... | 2004 | 15178679 |
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 ... | 2004 | 15168093 |
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 ... | 2004 | 15166143 |
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 ... | 2004 | 15158274 |
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 ... | 2004 | 15155805 |
health symptoms caused by molds in a courthouse. | a majority of occupants of a newly renovated historic courthouse in calgary, alberta, canada, reported multiple (3 or more) health-related symptoms, and several reported more than 10 persistent symptoms. most required at least 1 day outside of the building to recover from their symptoms. molds that produce mycotoxins, such as stachybotrys chartarum and emericella nidulans, were identified in the building, along with fungal organisms of the genera aspergillus, penicillium, streptomyces, cladospor ... | 2003 | 15143857 |
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. | 2004 | 15139917 |
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 ... | 2004 | 15128560 |
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 ... | 2004 | 15123642 |
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 ... | 2004 | 15121085 |
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. | 2004 | 15118339 |
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 ... | 2004 | 15105129 |
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 ... | 2004 | 15103156 |
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. | 2004 | 15075286 |
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. | 2004 | 15075284 |
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 ... | 2004 | 15075269 |
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 ... | 2004 | 15071756 |
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 ... | 2004 | 15068336 |
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 ... | 2004 | 15067540 |
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 ... | 2004 | 15066039 |
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 ... | 2004 | 15063139 |
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 ... | 2004 | 15054261 |
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 ... | 2004 | 15052376 |
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 ... | 2004 | 15050539 |
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 ... | 2004 | 15050035 |
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 ... | 2004 | 15049823 |
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- ... | 2004 | 15049821 |
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 ... | 2004 | 15048196 |
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 ... | 2004 | 15048194 |
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 ... | 2004 | 15045526 |
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 ... | 2004 | 15035355 |
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 ... | 2004 | 15025175 |
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 ... | 2004 | 15022028 |
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 ... | 2004 | 15020411 |
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) ... | 2004 | 15019993 |
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 ... | 2004 | 15019743 |
genetics and physiology of aflatoxin biosynthesis. | aflatoxins are the most thoroughly studied mycotoxins. elegant early research on the biosynthetic scheme of the pathway has allowed a molecular characterization of aflatoxin biosynthesis and its regulation. genetic studies on aflatoxin biosynthesis in aspergillus flavus and a. parasiticus, and sterigmatocystin biosynthesis in a. nidulans, led to the cloning of 17 genes responsible for 12 enzymatic conversions in the af/st pathways. pathway-specific regulation is by a zn(ii)2cys6 dna-binding prot ... | 1998 | 15012504 |
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 ... | 2004 | 15003443 |
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 ... | 2004 | 14998529 |