TitleAbstractYear(sorted descending)
parasexuality in asexual development mutants of aspergillus nidulans.the parasexual cycle with parameiosis has been characterized previously by the occurrence of genetic recombination and haploidization inside heterokaryotic hyphae prior to conidial formation. the aim of current research was to characterize, through genetic and cytological analyses, an asexual development mutant strain of a. nidulans and to use it to obtain parameiotic segregants. analyses showed the medusa phenotype of the b84 strain, whose mutant allele was mapped in the chromosome i. the heter ...200616874405
generation and analysis of expressed sequence tags from botrytis cinerea.botrytis cinerea is a filamentous plant pathogen of a wide range of plant species, and its infection may cause enormous damage both during plant growth and in the post-harvest phase. we have constructed a cdna library from an isolate of b. cinerea and have sequenced 11,482 expressed sequence tags that were assembled into 1,003 contigs sequences and 3,032 singletons. approximately 81% of the unigenes showed significant similarity to genes coding for proteins with known functions: more than 50% of ...200616874411
nmr metabolic profiling of aspergillus nidulans to monitor drug and protein activity.we describe a general protocol for using comparative nmr metabolomics data to infer in vivo efficacy, specificity and toxicity of chemical leads within a drug discovery program. the methodology is demonstrated using aspergillus nidulans to monitor the activity of urate oxidase and orotidine-5'-phosphate decarboxylase and the impact of 8-azaxanthine, an inhibitor of urate oxidase. 8-azaxanthine is shown to inhibit a. nidulans hyphal growth by in vivo inactivation of urate oxidase.200616889413
fungal surface remodelling visualized by atomic force microscopy.most fungal growth is localized to the tips of hyphae, however, early stages of spore germination and the growth of certain morphological mutant strains exhibit non-polarized expansion. we used atomic force microscopy (afm) to document changes in aspergillus nidulans wall surfaces during non-polarized growth: spore germination, and growth in a strain containing the hypa1 temperature sensitive morphogenesis defect. we compared wall surface structures of both wild-type and mutant a. nidulans follo ...200616891105
fungal metabolic model for tyrosinemia type 3: molecular characterization of a gene encoding a 4-hydroxy-phenyl pyruvate dioxygenase from aspergillus nidulans.mutations in the human hpd gene (encoding 4-hydroxyphenylpyruvic acid dioxygenase) cause hereditary tyrosinemia type 3 (ht3). we deleted the aspergillus nidulans homologue (hpda). we showed that the mutant strain is not able to grow in the presence of phenylalanine and that it accumulates increased concentrations of tyrosine and 4-hydroxyphenylpyruvic acid, mimicking the human ht3 phenotype.200616896227
cloning, sequence analysis and heterologous expression of the myrothecium gramineum orotidine-5'-monophosphate decarboxylase gene.a 2918 bp sequence coding for the orotidine-5'-monophosphate decarboxylase enzyme (ompd) was isolated from the genome of myrothecium gramineum. this sequence was analysed and, remarkably, it is the first ompd gene of a sordariomycete that has an intron. the gene codes for an enzyme of 282 amino acids. the nucleotide sequence and the amino acid sequence were compared with fungal ompd sequences. they show the highest similarity to ompd genes and enzymes of aspergillus sp., penicillium sp. and clad ...200616907730
aspergillus genomes: secret sex and the secrets of sex.the genomic sequences of three species of aspergillus, including the model organism a. nidulans (which is homothallic: having no differentiated mating types, a strain being able to cross with itself), suggest that a. fumigatus and a. oryzae, considered to be asexual, might in fact be heterothallic (having two differentiated mating types, a strain being able to cross only with strains of opposite mating type). the genomic data have implications for the understanding of the evolution and the mecha ...200616911845
comparative kinetic analysis of azga and fcy21p, prototypes of the two major fungal hypoxanthine-adenine-guanine transporter fungi, uptake of salvageable purines is carried out by members of two evolutionarily distinct protein families, the purine-related transporters (prt/ncs1) and the azga-like transporters. we carried out a comparative kinetic analysis of two prototypes of these transporter families. the first was fcy21p, a herein characterized protein of candida albicans, and the second was azga, a transporter of aspergillus nidulans. our results showed that: (i) azga and fcy21p are equally efficient high-affin ...200616923723
the first transmembrane segment (tms1) of uapa contains determinants necessary for expression in the plasma membrane and purine transport.uapa, a member of the nat/ncs2 family, is a high affinity, high capacity, uric acid-xanthine/h+ symporter in aspergillus nidulans. determinants critical for substrate binding and transport lie in a highly conserved signature motif downstream from tms8 and within tms12. here we examine the role of tms1 in uapa biogenesis and function. first, using a mutational analysis, we studied the role of a short motif (q85h86), conserved in all nats. q85 mutants were cryosensitive, decreasing (q85l, q85n, q8 ...200616923727
investigation of the functional properties and regulation of three glutamine synthetase-like genes in streptomyces coelicolor a3(2).streptomyces coelicolor a3(2) has three additional glna-type genes besides the glutamine synthetase genes glna (encoding gsi) and glnii (encoding gsii). the aim of this work was to characterize their functional properties and regulation. sequence analyses revealed that glna2, glna3, and glna4 are dissimilar to s. coelicolor gsi and lack highly conserved amino acid residues involved in catalysis. in heterologous expression experiments, glna2, glna3, and glna4, in contrast to glna and glnii, were ...200616932908
a caps test allowing a rapid distinction of penicillium expansum among fungal species collected on grape berries, inferred from the sequence and secondary structure of the mitochondrial ssu-rrna.penicillium expansum is a fungal species highly damageable for the postharvest conservation of numerous fruits. in vineyards, this fungus is sometimes isolated from grape berries where its presence may lead to the production of geosmin, a powerful earthy odorant, which can impair grapes and wines aromas. however, the discrimination of p. expansum from related fungi is difficult because it is based on ambiguous phenotypic characters and/or expensive and time-consuming molecular tests. in this con ...200616935376
plant growth-promoting methylobacterium induces defense responses in groundnut (arachis hypogaea l.) compared with rot pathogens.this study, framed in two different phases, studied the plant-growth promotion and the induction of systemic resistance in groundnut by methylobacterium. seed imbibition with methylobacterium sp. increased germination by 19.5% compared with controls. combined inoculation of methylobacterium sp. with rhizobium sp. also significantly increased plant growth, nodulation, and yield attributes in groundnut compared with individual inoculation of rhizobium sp. methylobacterium sp. challenge-inoculated ...200616941245
posaconazole for treatment of refractory invasive fungal disease.invasive fungal infections are usually associated with immunocompromised states about 40-60% of these patients are refractory to standard antifungal therapy we describe the effect of posaconazole in the treatment of a 12 years-old girl with uncontrolled diabetes mellitus with life-threatening cerebral mucor mycosis and a 4 year old girl boy with chronic granulomatous disease presenting with invasive aspergillus nidulans infection.200616961581
phylogenomic analysis of non-ribosomal peptide synthetases in the genus aspergillus.fungi from the genus aspergillus are important saprophytes and opportunistic human fungal pathogens that contribute in these and other diverse ways to human well-being. part of their impact on human well-being stems from the production of small molecular weight secondary metabolites, which may contribute to the ability of these fungi to cause invasive fungal infections and allergic diseases. in this study, we identified one group of enzymes responsible for secondary metabolite production in five ...200616962256
nonsense-mediated mrna decay mutation in aspergillus aspergillus nidulans mutation, designated nmda1, has been selected as a partial suppressor of a frameshift mutation and shown to truncate the homologue of the saccharomyces cerevisiae nonsense-mediated mrna decay (nmd) surveillance component nmd2p/upf2p. nmda1 elevates steady-state levels of premature termination codon-containing transcripts, as demonstrated using mutations in genes encoding xanthine dehydrogenase (hxa), urate oxidase (uaz), the transcription factor mediating regulation of ge ...200616963627
evidence for novel ph-dependent regulation of candida albicans rim101, a direct transcriptional repressor of the cell wall beta-glycosidase phr2.candida albicans is a commensal fungus of mucosal surfaces that can cause disease in susceptible hosts. one aspect of the success of c. albicans as both a commensal and a pathogen is its ability to adapt to diverse environmental conditions, including dramatic variations in environmental ph. the response to a neutral-to-alkaline ph change is controlled by the rim101 signal transduction pathway. in neutral-to-alkaline environments, the zinc finger transcription factor rim101 is activated by the pr ...200616963637
secondary metabolic gene cluster silencing in aspergillus contrast to most primary metabolism genes, the genes involved in secondary metabolism and certain nutrient utilization pathways are clustered in fungi. recently a nuclear protein, laea, was found to be required for the transcription of several secondary metabolite gene clusters in aspergillus nidulans. here we show that laea regulation does not extend to nutrient utilization or the spoc1 sporulation clusters. one of the secondary metabolite clusters regulated by laea contains the positive reg ...200616968230
the aflatoxin biosynthesis cluster gene, aflx, encodes an oxidoreductase involved in conversion of versicolorin a to demethylsterigmatocystin.biosynthesis of the toxic and carcinogenic aflatoxins by the fungus aspergillus flavus is a complicated process involving more that 27 enzymes and regulatory factors encoded by a clustered group of genes. previous studies found that three enzymes, encoded by vera, ver-1, and afly, are required for conversion of versicolorin a (va), to demethylsterigmatocystin. we now show that a fourth enzyme, encoded by the previously uncharacterized gene, aflx (ordb), is also required for this conversion. a ho ...200616461654
a novel-type substrate-selectivity filter and er-exit determinants in the uapa purine transporter.we present a functional analysis of the last alpha-helical transmembrane segment (tms12) of uapa, a uric acid-xanthine/h+ symporter in aspergillus nidulans and member of the nucleobase-ascorbate transporter (nat) family. first, we performed a systematic mutational analysis of residue f528, located in the middle of tms12, which was known to be critical for uapa specificity. substitution of f528 with non-aromatic amino acid residues (ala, thr, ser, gln, asn) did not affect significantly the kineti ...200616464466
the aspergillus nidulans xprg (phog) gene encodes a putative transcriptional activator involved in the response to nutrient limitation.the aspergillus nidulans xprg gene is involved in the regulation of extracellular proteases. a plasmid which complemented the xprg2 mutation was shown to carry the phog gene, reported to encode an acid phosphatase. two phogdelta mutants were constructed and were identical in phenotype to an xprg2 mutant. null mutants were unable to use protein as a carbon or nitrogen source, have lost a repressible acid phosphatase and have pale conidial color. xprg shows similarity to the ndt80 transcriptional ...200616464624
intrinsic in vitro susceptibility of primary clinical isolates of aspergillus fumigatus, aspergillus terreus, aspergillus nidulans, candida albicans and candida lusitaniae against amphotericin b.a total of 60 clinical fungal isolates from patients without prior amphotericin b treatment and three control strains were evaluated for their intrinsic susceptibility to amphotericin b (amb) using microdilution, etest and disc diffusion assays, on three media each, roswell park memorial institute (rpmi) 1640, antibiotic medium 3 (am3) and high resolution medium. the fungal strains included isolates of aspergillus fumigatus (n = 10), aspergillus terreus (n = 12), aspergillus nidulans (n = 9), ca ...200616466441
clip-170 homologue and nude play overlapping roles in nudf localization in aspergillus nidulans.proteins in the cytoplasmic dynein pathway accumulate at the microtubule plus end, giving the appearance of comets when observed in live cells. the targeting mechanism for nudf (lis1/pac1) of aspergillus nidulans, a key component of the dynein pathway, has not been clear. previous studies have demonstrated physical interactions of nudf/lis1/pac1 with both nude/nudel/ndl1 and clip-170/bik1. here, we have identified the a. nidulans clip-170 homologue, clipa. the clipa deletion did not cause an obv ...200616467375
differential expression of aspergillus nidulans ammonium permease genes is regulated by gata transcription factor area.the movement of ammonium across biological membranes is mediated in both prokaryotes and eukaryotes by ammonium transport proteins (amt/mep) that constitute a family of related sequences. we have previously identified two ammonium permeases in aspergillus nidulans, encoded by the meaa and mepa genes. here we show that meaa is expressed in the presence of ammonium, consistent with the function of meaa as the main ammonium transporter required for optimal growth on ammonium as a nitrogen source. i ...200616467464
the phosducin-like protein phna is required for gbetagamma-mediated signaling for vegetative growth, developmental control, and toxin biosynthesis in aspergillus nidulans.phosducin or phosducin-like protein (phlp) is a positive regulator of gbetagamma activity. the gbeta (sfad) and ggamma (gpga) subunits function in vegetative growth and developmental control in the model filamentous fungus aspergillus nidulans. to better understand the nature of gbetagamma-mediated signaling, phna, encoding an a. nidulans phlp, has been studied. deletion of phna resulted in phenotypes almost identical to those caused by deletion of sfad, i.e., reduced biomass, asexual sporulatio ...200616467480
aspergillus nidulans class v and vi chitin synthases csma and csmb, each with a myosin motor-like domain, perform compensatory functions that are essential for hyphal tip growth.the polarized synthesis of cell wall components such as chitin is essential for the hyphal tip growth of filamentous fungi. the actin cytoskeleton is known to play important roles in the determination of hyphal polarity in aspergillus nidulans. previously, we suggested that csma, a chitin synthase with a myosin motor-like domain (mmd), was involved in polarized chitin synthesis in a manner dependent on the interaction between the mmd and the actin cytoskeleton. the genome database indicates that ...200616468983
genetic transformation of ascochyta rabiei using agrobacterium-mediated order to study pathogenic mechanisms of the plant pathogen ascochyta rabiei, conditions for efficient transformation using agrobacterium-mediated transformation were investigated. hygromycin b resistance (hph) was superior to geneticin resistance (nptii) for selecting transformants, and the hph gene was more efficiently expressed by the aspergillus nidulans trpc promoter than by the cauliflower mosaic virus 35s promoter camv35s. co-cultivation on solid media for 72 h was optimal for generatin ...200616369840
impact of fungal drug transporters on fungicide sensitivity, multidrug resistance and virulence.drug transporters are membrane proteins that provide protection for organisms against natural toxic products and fungicides. in plant pathogens, drug transporters function in baseline sensitivity to fungicides, multidrug resistance (mdr) and virulence on host plants. this paper describes drug transporters of the filamentous fungi aspergillus nidulans (eidam) winter, botrytis cinerea pers and mycosphaerella graminicola (fückel) schroter that function in fungicide sensitivity and resistance. the f ...200616475240
nonribosomal peptide synthesis in schizosaccharomyces pombe and the architectures of ferrichrome-type siderophore synthetases in fungi.a nonribosomal peptide synthetase (nrps) in schizosaccharomyces pombe, which possesses an unusual structure incorporating three adenylation domains, six thiolation domains and six condensation domains, has been shown to produce the cyclohexapeptide siderophore ferrichrome. one of the adenylation domains is truncated and contains a distorted key motif. substrate-binding specificities of the remaining two domains were assigned by molecular modelling to glycine and to n-acetyl-n-hydroxy-l-ornithine ...200616502473
common features and interesting differences in transcriptional responses to secretion stress in the fungi trichoderma reesei and saccharomyces cerevisiae.secretion stress is caused by compromised folding, modification or transport of proteins in the secretory pathway. in fungi, induction of genes in response to secretion stress is mediated mainly by the unfolded protein response (upr) pathway. this study aims at uncovering transcriptional responses occurring in the filamentous fungi trichoderma reesei exposed to secretion stress and comparing these to those found in the yeast saccharomyces cerevisiae.200616504068
induction of temperate cyanophage as-1 by heavy has been reported that some marine cyanophage are temperate and can be induced from a lysogenic phase to a lytic phase by different agents such as heavy metals. however, to date no significant reports have focused on the temperate nature of freshwater cyanophage/cyanobacteria. previous experiments with cyanophage as-1 and cyanobacteria anacystis nidulans have provided some evidence that as-1 may have a lysogenic life cycle in addition to the characterized lytic cycle.200616504132
depletion of aspergillus nidulans cota causes a severe polarity defect which is not suppressed by the nuclear migration mutation nuda2.the aspergillus nidulans homologue of neurospora crassa cot-1, cota, encoding a member of the ndr protein kinase family, has been cloned and expressed under the control of the conditional alca promoter. depletion of cota by repression of the alca promoter led to a severe growth defect accompanied by loss of polarity. germlings show greatly enlarged volume of the spores and hyphae, accompanied by an increase in number of nuclei per compartment, though the nucleus/volume ratio is not significantly ...200616506053
functional characterization of the putative aspergillus nidulans poly(adp-ribose) polymerase homolog prpa.poly(adp-ribose) polymerase (parp) is a highly conserved enzyme involved in multiple aspects of animal and plant cell physiology. for example, parp is thought to be intimately involved in the early signaling events that trigger the dna damage response. however, the genetic dissection of parp function has been hindered by the presence of multiple homologs in most animal and plant species. here, we present the first functional characterization of a putative parp homolog (prpa) in a microbial syste ...200616510786
the product of the shr3 orthologue of aspergillus nidulans has restricted range of amino acid transporter targets.the shra gene of aspergillus nidulans codes for a structural and functional homologue of shr3p, a yeast er membrane protein, which plays a crucial role in the secretory pathway of yeast amino acid permeases. shra is a single-copy gene, whose expression is early activated during germination of a. nidulans conidiospores. shra is localized in the er of the fungal cells and partially complements the shr3delta phenotype. differently from saccharomyces cerevisiae, where shr3p is necessary for membrane ...200616531082
functional analysis of alcs, a gene of the alc cluster in aspergillus nidulans.the ethanol utilization pathway (alc system) of aspergillus nidulans requires two structural genes, alca and alda, which encode the two enzymes (alcohol dehydrogenase and aldehyde dehydrogenase, respectively) allowing conversion of ethanol into acetate via acetyldehyde, and a regulatory gene, alcr, encoding the pathway-specific autoregulated transcriptional activator. the alcr and alca genes are clustered with three other genes that are also positively regulated by alcr, although they are dispen ...200616531087
analysis of the aspergillus nidulans thaumatin-like ceta gene and evidence for transcriptional repression of pyr4 expression in the ceta-disrupted strain.the asexual spore or conidium plays a critical role in the life cycle of many filamentous fungi. however, the process of conidial germination remains surprisingly obscure. to better understand this process at the molecular level we characterized the aspergillus nidulans ceta gene which is uniquely transcribed in conidiating cultures and whose transcript is significantly enriched in mature conidia. ceta is a member of a novel family of fungal genes of unknown function with homology to plant thaum ...200616376592
g-protein and camp-mediated signaling in aspergilli: a genomic perspective.we have carried out an in silico exploration of the genomes of aspergillus nidulans, aspergillus fumigatus, and aspergillus oryzae, and identified components of g-protein/camp-mediated signaling. putative g-protein coupled receptors (gpcrs) were distributed over nine classes. the gpcrs within classes were well conserved among aspergilli but varied in other ascomycetes. as previously observed in a. nidulans and other fungi, three galpha, one gbeta, and one ggamma subunits of g proteins were ident ...200616546420
[recombinant aspergillus niger glucose oxidase expressed in trichoderma reesei].it was expected that recombinant aspergillus niger glucose oxidase could be expressed in trichoderma reesei with stable activity. t. reesei cbhi promoter--cbhi ss. gene--a. niger glucose oxidase gene--t. reesei cbhi terminator--a. nidulans gpd promoter--e. coli hygromycin b phosphotransferase gene--a. nidulans trpc terminator--puc19 (pcbhgod) vector was constructed in e. coli dh5alpha by pcr application and gene cloning methods. t. reesei qm9414 protoplast was transformed by t. reesei cbhi promo ...200616572845
protein kinase c (pkca) of aspergillus nidulans is involved in penicillin production.the biosynthesis of the beta-lactam antibiotic penicillin in the filamentous fungus aspergillus nidulans is catalyzed by three enzymes that are encoded by the acva, ipna, and aata genes. a variety of cis-acting dna elements and regulatory factors form a complex regulatory network controlling these beta-lactam biosynthesis genes. regulators involved include the ccaat-binding complex ancf and anbh1. anbh1 acts as a repressor of the penicillin biosynthesis gene aata. until now, however, little info ...200616598003
antimicrobial, wound healing and antioxidant activity of plagiochasma appendiculatum lehm. et lind.plagiochasma appendiculatum (aytoniaceae) of the order marchantiales is widely used in the form of paste ethnomedicinally by gaddi tribe in kangra valley for treating skin diseases. in this context, antimicrobical potential of plagiochasma appendiculatum against a wide range of microorganisms was studied. to validate the ethnotherapeutic claims of the plant in skin diseases, wound healing activity was studied, besides antioxidant activity to understand the mechanism of wound healing activity. th ...200616600543
microscopy reveals disease control through novel effects on fungal development: a case study with an early-generation benzophenone fungicide.the benzophenones are a new class of agricultural fungicides that demonstrate protectant, curative and eradicative/antisporulant activity against powdery mildews. the chemistry is represented in the marketplace by the fungicide metrafenone, recently introduced by basf and discussed in the following paper. the benzophenones show no evidence of acting by previously identified biochemical mechanisms, nor do they show cross-resistance with existing fungicides. the value of microscopy in elucidating ...200616602068
isolation of mutations that bypass the requirement of the septation initiation network for septum formation and conidiation in aspergillus nidulans.the kinase cascade of the septation initiation network (sin), first revealed in fission yeast, activates the contraction of the actomyosin ring, and plays an essential role in fungal septation. mob1p, an evolutionarily conserved sin protein, is associated with the most downstream kinase of this cascade in fission yeast. in this study, the moba gene encoding a homologous protein was isolated from the filamentous fungus aspergillus nidulans, whose mycelium is made of multinucleate cells. the moba ...200616624915
the region in a subunit of the aspergillus ccaat-binding protein similar to the hap4p-recruiting domain of saccharomyces cerevisiae hap5p is not essential for transcriptional enhancement.the ccaat-binding complex in aspergillus species, known as the hap complex, consists of at least three subunits, hapb, hapc, and hape. each hap subunit contains an evolutionarily conserved core domain. in this study, a series of the truncated gene, which encodes the hape subunit of aspergillus oryzae, was constructed to survey the regions essential for the transcriptional enhancement of fungal genes. it was revealed that the non-conserved regions and the conserved region similar to the hap4p rec ...200616636442
comparative studies of differential expression of chitinolytic enzymes encoded by chia, chib, chic and naga genes in aspergillus nidulans.n-acetyl-d-glucosamine, chito-oligomers and carbon starvation regulated chia, chib, and naga gene expressions in aspergillus nidulans cultures. the gene expression patterns of the main extracellular endochitinase chib and the n-acetyl-beta-d-glucosaminidase naga were similar, and the chib-naga enzyme system may play a morphological and/or nutritional role during autolysis. alterations in the levels of reactive oxygen species or in the glutathione-glutathione disulfide redox balance, characterist ...200617455791
developmental regulation of the glyoxylate cycle in the human pathogen penicillium marneffei.penicillium marneffei is a thermally dimorphic opportunistic human pathogen with a saprophytic filamentous hyphal form at 25 degrees c and a pathogenic unicellular yeast form at 37 degrees c. during infection. p. marneffei yeast cells exist intracellularly in macrophages. to cope with nutrient deprivation during the infection process, a number of pathogens employ the glyoxylate cycle to utilize fatty acids as carbon sources. the genes which constitute this pathway have been implicated in pathoge ...200617427290
eurotiomycetes: eurotiomycetidae and chaetothyriomycetidae.the class eurotiomycetes (ascomycota, pezizomycotina) is a monophyletic group comprising two major clades of very different ascomycetous fungi: (i) the subclass eurotiomycetidae, a clade that contains most of the fungi previously recognized as plectomycetes because of their mostly enclosed ascomata and prototunicate asci; and (ii) the subclass chaetothyriomycetidae, a group of fungi that produce ascomata with an opening reminiscent of those produced by dothideomycetes or sordariomycetes. in this ...200617486980
regulatory genes controlling fatty acid catabolism and peroxisomal functions in the filamentous fungus aspergillus nidulans.the catabolism of fatty acids is important in the lifestyle of many fungi, including plant and animal pathogens. this has been investigated in aspergillus nidulans, which can grow on acetate and fatty acids as sources of carbon, resulting in the production of acetyl coenzyme a (coa). acetyl-coa is metabolized via the glyoxalate bypass, located in peroxisomes, enabling gluconeogenesis. acetate induction of enzymes specific for acetate utilization as well as glyoxalate bypass enzymes is via the zn ...200616682457
in vitro activation, purification, and characterization of escherichia coli expressed aryl-alcohol oxidase, a unique h2o2-producing enzyme.aryl-alcohol oxidase (aao), a flavoenzyme with unique spectral and catalytic properties that provides h2o2 for fungal degradation of lignin, has been successfully activated in vitro after escherichia coli expression. the recombinant aao (aao*) protein was recovered from inclusion bodies of e. coli w3110 transformed with pflag1 containing the aao cdna from pleurotus eryngii. optimization of in vitro refolding yielded 75% active enzyme after incubation of aao* protein (10 microg/ml) for 80 h (at 1 ...200616039872
structure-activity relationships and enzyme inhibition of pantothenamide-type pantothenate kinase inhibitors.a set of novel pantothenamide-type analogues of the known staphylococcus aureus pantothenate kinase (sapank) inhibitors, n-pentyl, and n-heptylpantothenamide, was synthesized in three series. the first series of analogues (1-3) were designed as molecular probes of the pank binding site to elucidate important structure-activity relationships (sar). the second series of analogues (4-16) were designed using structural information obtained from the escherichia coli pank (ecpank) structure by targeti ...200616213731
efficient pcr-based gene targeting with a recyclable marker for aspergillus nidulans.the rapid accumulation of genomic sequences from a large number of eukaryotes, including numerous filamentous fungi, has created a tremendous scientific potential, which can only be realized if precise site-directed genome modifications, like gene deletions, promoter replacements, in-frame gfp fusions and specific point mutations can be made rapidly and reliably. the development of gene-targeting techniques in filamentous fungi and other higher eukaryotes has been hampered because foreign dna is ...200616289954
g protein-coupled receptor gpr4 senses amino acids and activates the camp-pka pathway in cryptococcus neoformans.the galpha protein gpa1 governs the camp-pka signaling pathway and plays a central role in virulence and differentiation in the human fungal pathogen cryptococcus neoformans, but the signals and receptors that trigger this pathway were unknown. we identified seven putative proteins that share identity with known g protein-coupled receptors (gpcrs). one protein, gpr4, shares limited sequence identity with the dictyostelium discoideum camp receptor car1 and the aspergillus nidulans gpcr protein gp ...200616291861
visualization of the endocytic pathway in the filamentous fungus aspergillus oryzae using an egfp-fused plasma membrane protein.endocytosis is an important process for cellular activities. however, in filamentous fungi, the existence of endocytosis has been so far elusive. in this study, we used aouapc-egfp, the fusion protein of a putative uric acid-xanthine permease with enhanced green fluorescent protein (egfp) in aspergillus oryzae, to examine whether the endocytic process occurs or not. upon the addition of ammonium into the medium the fusion protein was internalized from the plasma membrane. the internalization of ...200616380079
flug-dependent asexual development in aspergillus nidulans occurs via derepression.the asexual spore is one of the most crucial factors contributing to the fecundity and fitness of filamentous fungi. although the developmental activator flug was shown to be necessary for activation of asexual sporulation (conidiation) and production of the carcinogenic mycotoxin sterigmatocystin (st) in the model filamentous fungus aspergillus nidulans, the molecular mechanisms underlying the developmental switch have remained elusive. in this study, we report that the flug-mediated conidiatio ...200616387865
a versatile and efficient gene-targeting system for aspergillus nidulans.aspergillus nidulans is an important experimental organism, and it is a model organism for the genus aspergillus that includes serious pathogens as well as commercially important organisms. gene targeting by homologous recombination during transformation is possible in a. nidulans, but the frequency of correct gene targeting is variable and often low. we have identified the a. nidulans homolog (nkua) of the human ku70 gene that is essential for nonhomologous end joining of dna in double-strand b ...200616387870
the gata factor area regulates localization and in vivo binding site occupancy of the nitrate activator nira.the gata factor area is a wide-domain regulator in aspergillus nidulans with transcriptional activation and chromatin remodelling functions. area interacts with the nitrate-specific zn(2)-c(6) cluster protein nira and both proteins cooperate to synergistically activate nitrate-responsive genes. we have previously established that nira in vivo dna binding site occupancy is area dependent and in this report we provide a mechanistic explanation for our previous findings. we now show that area regul ...200616390440
distinct ceramide synthases regulate polarized growth in the filamentous fungus aspergillus filamentous fungi, the stabilization of a polarity axis is likely to be a pivotal event underlying the emergence of a germ tube from a germinating spore. recent results implicate the polarisome in this process and also suggest that it requires localized membrane organization. here, we employ a chemical genetic approach to demonstrate that ceramide synthesis is necessary for the formation of a stable polarity axis in the model fungus aspergillus nidulans. we demonstrate that a novel compound ( ...200616394102
the presence of gc-ag introns in neurospora crassa and other euascomycetes determined from analyses of complete genomes: implications for automated gene prediction.a combination of experimental and computational approaches was employed to identify introns with noncanonical gc-ag splice sites (gc-ag introns) within euascomycete genomes. evaluation of 2335 cdna-confirmed introns from neurospora crassa revealed 27 such introns (1.2%). a similar frequency (1.0%) of gc-ag introns was identified in fusarium graminearum, in which 3 of 292 cdna-confirmed introns contained gc-ag splice sites. computational analyses of the n. crassa genome using a gc-ag intron conse ...200616406724
regulation of hyphal morphogenesis and the dna damage response by the aspergillus nidulans atm homolog atma.ataxia telangiectasia (a-t) is an inherited disorder characterized by progressive loss of motor function and susceptibility to cancer. the most prominent clinical feature observed in a-t patients is the degeneration of purkinje motor neurons. numerous studies have emphasized the role of the affected gene product, atm, in the regulation of the dna damage response. however, in purkinje cells, the bulk of atm localizes to the cytoplasm and may play a role in vesicle trafficking. the nature of this ...200616415361
identification of the mste gene encoding a glucose-inducible, low affinity glucose transporter in aspergillus nidulans.the mste gene encoding a low affinity glucose transporter active during the germination of aspergillus nidulans conidia on glucose medium has been identified. mste expression also occurs in hyphae, is induced in the presence of other repressing carbon sources besides glucose, and is dependent on the function of the transcriptional repressor crea. the expression of mste and its subcellular distribution have been studied using a mste-sgfp fusion protein. concordant with data on mste expression, ms ...200616418173
farnesol-induced apoptosis in aspergillus nidulans reveals a possible mechanism for antagonistic interactions between fungi.the dimorphic fungus candida albicans secretes farnesol, which acts as a quorum-sensing molecule and prevents the yeast to mycelium conversion. in this study we examined the effect of farnesol in the filamentous fungus aspergillus nidulans. we show that externally added farnesol has no effect on hyphal morphogenesis; instead, it triggers morphological features characteristic of apoptosis. additional experiments suggest that mitochondria and reactive oxygen species (ros) participate in farnesol-i ...200616420349
tmpa, a member of a novel family of putative membrane flavoproteins, regulates asexual development in aspergillus nidulans.asexual reproduction (conidiation) in aspergillus nidulans is induced by environmental signals like exposure to air or nutrient starvation, and depends on brla gene activation. the study of 'fluffy' mutants showing delayed asexual development and reduced brla expression has defined the flug pathway, involved in regulation of this differentiation process. genetic characterization of a 'fluffy' mutant identified tmpa as a new gene involved in regulation of conidiation. tmpa defines a new family of ...200616420356
oxylipins act as determinants of natural product biosynthesis and seed colonization in aspergillus nidulans.secreted, hormone-like lipogenic molecules, called oxylipins, mediate the balance of asexual to sexual spore ratio in aspergillus nidulans. oxylipin production in this fungus is dependent on developmental regulation of three conserved fatty acid oxygenases, ppoa, ppob and ppoc. here, we show that in addition to altering spore ratios, loss of ppo genes affect natural product biosynthesis and seed colonization. deltappoa;deltappoc and deltappoa;deltappob;deltappoc mutants were unable to produce th ...200616420358
a global view of metabolites.fungi are rich sources of medically useful, as well as toxic, secondary metabolites. in this issue of chemistry & biology, bok et al. show that, in aspergillus nidulans, microarray analysis and manipulation of a global regulator can identify novel metabolite genes.200616426964
genomic mining for aspergillus natural products.the genus aspergillus is renowned for its ability to produce a myriad of bioactive secondary metabolites. although the propensity of biosynthetic genes to form contiguous clusters greatly facilitates assignment of putative secondary metabolite genes in the completed aspergillus genomes, such analysis cannot predict gene expression and, ultimately, product formation. to circumvent this deficiency, we have examined aspergillus nidulans microarrays for expressed secondary metabolite gene clusters b ...200616426969
evaluation of agrobacterium-mediated transformation of agaricus bisporus using a range of promoters linked to hygromycin resistance.there is interest in establishing genetic modification technologies for the cultivated mushroom agaricus bisporus, both for improved crop characteristics and for molecular pharming. for these methods to be successful, it is necessary to establish a set of transformation systems that include robust and reliable vectors for gene manipulation. in this article, we report the evaluation of a series of promoters for driving expression of the escherichia coli hph gene encoding hygromycin phosphotransfe ...200616444014
detection of unknown toxic mycotoxins inaspergillus nidulans using a structure-activity approach.mycotoxins are secondary metabolites of filamentous fungi that can cause various acute and chronic toxic effects in humans. previous work by büngeret al. exhibited that the cytotoxicityof aspergillus nidulans, one of the most frequent toxigenic moulds in composting plants, could not be explained by its content of identified mycotoxins. the presence of additional mycotoxins or other toxic prinpiples was assumed, which may be detected by a structure-activity hplc-diode array detector m ...200623605709
occurrence of fungal species and mycotoxins from decayed sugarcane (saccharrum officinarum) in egypt.seventy-three fungal species belonging to forty-three genera were isolated from 40 samples of saccharrum officinarum (collected from naage-hamadi canal in qena governorate, egypt). aspergillus, trichoderma, mucor and pythium were the most common genera on the two isolation media. the dominant species of aspergillus were a. niger, a. flavus, a. ustus, a. terreus and a. wentii. some species were dominant on 40 g/l sucrose such as aspergillus niger, a. flavus, emericella nidulans, trichoderma virid ...200524049478
glass-fiber disks provide suitable medium to study polyol production and gene expression in eurotium rubrum.eurotium species often dominate the fungal population in stored grain and are responsible for spoilage. in this study we tested the usefulness of glass fiber disks to aid the analysis of growth, polyol content and gene expression in e. rubrum in response to various water activities. growth measurements based on ergosterol content and conidial production indicated that e. rubrum grew as well at 0.86 aw as 0.98 aw. the rate of growth was considerably reduced at 0.83 aw and 0.78 aw. in contrast, un ...200516457343
genomics reveals traces of fungal phenylpropanoid-flavonoid metabolic pathway in the f ilamentous fungus aspergillus oryzae.fungal secondary metabolites constitute a wide variety of compounds which either play a vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. a majority of the funga ...200516410762
screening of growth- or development-related genes by using genomic library with inducible promoter in aspergillus nidulans.using the genomic library constructed at the downstream of the niia promoter, which induces the over-expression of an inserted dna fragment, we have attempted to screen the genes affecting growth or development by over-expression. the wild-type strain was transformed using the ama-niia(p) library and cultured on 1.2 m sorbitol media, in which asexual sporulation is induced, but sexual development is repressed. over 100,000 strains transformed to pyrg(+) were analyzed with regard to any changes i ...200516410769
deletions of endocytic components vps28 and vps32 affect growth at alkaline ph and virulence through both rim101-dependent and rim101-independent pathways in candida albicans.ambient ph signaling involves a cascade of conserved rim or pal products in ascomycetous yeasts or filamentous fungi, respectively. recent evidences in the fungi aspergillus nidulans, saccharomyces cerevisiae, yarrowia lipolytica, and candida albicans suggested that components of endosomal sorting complexes required for transport (escrt) involved in endocytic trafficking were needed for signal transduction along the rim pathway. in this study, we confirm these findings with c. albicans and show ...200516299290
c21orf5, a new member of dopey family involved in morphogenesis, could participate in neurological alterations and mental retardation in down syndrome.availability of the human genome sequence promises important progress in the understanding of human pathologies, particularly for multifactorial diseases. among these, down syndrome (ds) is the most frequent genetic cause of mental retardation. a critical region of chromosome 21, the down syndrome chromosomal region-1 (dcr-1), is responsible for many features of the ds phenotype including mental retardation. we studied dcr-1 c21orf5 as a new candidate gene for ds considering its restricted expre ...200516303751
tracing the endocytic pathway of aspergillus nidulans with fm4-64.simple procedures using fm4-64 to follow membrane internalization and transport to the vacuolar system and endomembranes in aspergillus nidulans are described. fm4-64 internalization is energy, temperature and f-actin dependent, strongly suggesting that it occurs by endocytosis. the dye sequentially labels: (i) cortical punctuate organelles whose motility resembles that of yeast actin patches; (ii) approximately 0.7 microm circular, hollow structures representing mature endosome/vacuole; and (ii ...200516291501
cloning, expression, and characterization of an oligoxyloglucan reducing end-specific xyloglucanobiohydrolase from aspergillus oligoxyloglucan reducing end-specific xyloglucanobiohydrolase from the filamentous fungus aspergillus nidulans was cloned and expressed in pichia pastoris as a secreted histidine-tagged protein and purified by affinity chromatography. the enzyme acts on xyloglucan oligomers and releases the first two glycosyl residue segments from the reducing end, provided that neither the first glucose nor the xylose attached to the third glucose residue from the reducing end is not further substituted. the ...200516214120
nuclear accumulation of the gata factor area in response to complete nitrogen starvation by regulation of nuclear export.both the availability and the quality of nutrients affect cellular functions by controlling gene activity. area, a member of the gata family of transcription factors, globally activates expression of genes involved in nitrogen source utilization in aspergillus nidulans. the quality of the nitrogen source determines the level and activation capacity of area through controls at the level of area mrna stability and by interaction of area with the corepressor nmra. the availability of potential nitr ...200516215172
hdaa, a major class 2 histone deacetylase of aspergillus nidulans, affects growth under conditions of oxidative stress.histone deacetylases (hdacs) catalyze the removal of acetyl groups from the epsilon-amino group of distinct lysine residues in the amino-terminal tail of core histones. since the acetylation status of core histones plays a crucial role in fundamental processes in eukaryotic organisms, such as replication and regulation of transcription, recent research has focused on the enzymes responsible for the acetylation/deacetylation of core histones. very recently, we showed that hdaa, a member of the sa ...200516215180
cloning and expression analysis of two catalase genes from aspergillus oryzae.fungi contain distinct genes encoding the same class of enzyme that are differentially regulated according to conditions. we cloned two catalase genes, cata and catb, from aspergillus oryzae. the cata gene predicts a 747-amino-acid polypeptide sharing 81% identity with aspergillus fumigatus catalase (cata) and 77% with aspergillus nidulans catalase (cata). the catb gene predicts a 725-amino-acid polypeptide sharing 82% identity with a. fumigatus catalase (catb) and 75% with a. nidulans catalase ...200516233832
photosensing fungi: phytochrome in the light triggers asexual development and represses sexual development in the fungus aspergillus nidulans. this response has been shown to require a phytochrome red/far-red light photoreceptor, fpha, which is cytoplasmic and binds a tetrapyrrole chromophore. fpha exhibits similarities to both plant and bacterial phytochromes.200516243020
the aspergillus nidulans phytochrome fpha represses sexual development in red light.phytochrome photoreceptors sense red and far-red light through photointerconversion between two stable conformations, a process mediated by a linear tetrapyrrole chromophore. originally, phytochromes were thought to be confined to photosynthetic organisms including cyanobacteria, but they have been recently discovered in heterotrophic bacteria and fungi, where little is known about their functions. it was shown previously in the ascomycetous fungus aspergillus nidulans that asexual sporulation i ...200516243030
protein o-mannosyltransferase a of aspergillus awamori is involved in o-mannosylation of glucoamylase i.industrially important extracellular enzymes from filamentous fungi are often o-mannosylated. the structure and function of the pmta (aapmta) gene encoding the protein o-d-mannosyltransferase of aspergillus awamori were characterized. the aapmta disruptant, designated aapmta, was constructed by homologous recombination. the strain aapmta exhibited fragile cell morphology with respect to hyphal extension, as well as swollen hyphae formation and conidia formation in potato dextrose medium. moreove ...200516272387
surface ultrastructure and elasticity in growing tips and mature regions of aspergillus hyphae describe wall maturation.this study reports the first direct, high-resolution physical and structural evidence of wall changes during hyphal tip growth, visualized by atomic force microscopy (afm) in aspergillus nidulans. images from afm and cryo-scanning electron microscopy provided comparable information, but afm was also able to image and physically probe living cells. afm images showed changes in the surface ultrastructure of a. nidulans hyphae, from newly deposited walls at hyphal tips to fully mature walls, as wel ...200516272389
crea influences the metabolic fluxes of aspergillus nidulans during growth on glucose and xylose.the physiological phenotype of aspergillus nidulans was investigated for different genetic and environmental conditions of glucose repression through the quantification of in vivo fluxes in the central carbon metabolism using (13)c-metabolic-flux analysis. the particular focus was the role of the carbon repressor crea, which is the major regulatory protein mediating carbon repression in many fungal species, in the primary metabolism of a. nidulans. batch cultivations were performed with a refere ...200516000711
amino acid catabolism by an area-regulated gene encoding an l-amino acid oxidase with broad substrate specificity in aspergillus nidulans.the filamentous fungus aspergillus nidulans can use a wide range of compounds as nitrogen sources. the synthesis of the various catabolic enzymes needed to breakdown these nitrogen sources is regulated by the area gene, which encodes a gata transcription factor required to activate gene expression under nitrogen-limiting conditions. the area102 mutation results in pleiotropic effects on nitrogen source utilization, including better growth on certain amino acids as nitrogen sources. mutations in ...200516000761
aspergillus nidulans uvsbatr and scaanbs1 genes show genetic interactions during recovery from replication stress and dna damage.the atm/atr kinases and the mre11 (mre11-rad50-nbs1) protein complex are central players in the cellular dna damage response. here we characterize possible interactions between aspergillus nidulans uvsb(atr) and the mre11 complex (scaa(nbs1)). we demonstrate that there is an epistatic relationship between uvsb(atr), the homolog of the atr/mec1 gene, and scaa(nbs1), the homolog of the nbs1/xrs2 gene, for both repair and checkpoint functions and that correct scaa(nbs1) expression during recovery f ...200516002650
differential expression of the chse gene encoding a chitin synthase of aspergillus nidulans in response to developmental status and growth conditions.expression of chse encoding one of the five chitin synthases of aspergillus nidulans was analyzed. expression of chse was moderate in conidiophores, but somewhat weaker in vegetative mycelia. during sexual development, chse was expressed strongly in young cleistothecia and hülle cells, but little in mature sexual structures. deletion of chse caused a significant decrease in the chitin content of the cell wall during early sexual development. expression of chse was increased by substituting gluco ...200516006063
methylcitrate synthase from aspergillus fumigatus. propionyl-coa affects polyketide synthesis, growth and morphology of conidia.methylcitrate synthase is a key enzyme of the methylcitrate cycle and required for fungal propionate degradation. propionate not only serves as a carbon source, but also acts as a food preservative (e280-283) and possesses a negative effect on polyketide synthesis. to investigate propionate metabolism from the opportunistic human pathogenic fungus aspergillus fumigatus, methylcitrate synthase was purified to homogeneity and characterized. the purified enzyme displayed both, citrate and methylcit ...200516008561
dynamic association of topoisomerase ii to the mitotic chromosomes in live cells of aspergillus nidulans.dna topoisomerase ii (topo ii) is an essential enzyme that catalyzes topological changes of dna and consists of a major member of mitotic chromosomes. to investigate the dynamic localization of topo ii in nuclei, we engineered the strain of aspergillus nidulans expressing topo ii fused with green fluorescent protein (gfp). time-lapse microscopy revealed that the distribution of topo ii-gfp in nuclei varied depending on the cell cycle. in interphase, topo ii-gfp distributed evenly in the nucleopl ...200516009350
[frequency and distribution of variable-number tandem repeats in the genome of aspergillus niculans].a total of 30.1 mb of publicly available dna sequence in aspergillus niculans was researched for mono- to hexanucleotide variable-number tandem repeat (vntr) to determine its type, size and frequency. a total of 4 837 vntrs were observed in whole genomic dna sequence with criteria of vntr length > 15 bp and 80% matches. considering all six classes of vntrs, they occur on average about once every 6.2 kb for mono- to hexanucleotide in genomic dna. the most abundance variable-number tandem repeat i ...200516018267
characterization of the ferrichrome a biosynthetic gene cluster in the homobasidiomycete omphalotus olearius.under iron deprivation omphalotus olearius was found to produce the hydroxamate siderophore ferrichrome a. a gene cluster consisting of three genes: fso1, a nonribosomal peptide synthetase whose expression is enhanced in the absence of iron; omo1, a l-ornithine-n(5)-monooxygenase; and ato1, an acyltransferase probably involved in the transfer of the methylglutaconyl residue to n(5)-hydroxyorinithine was identified. the fso1 sequence is interrupted by 48 introns and its derived protein sequence h ...200516019163
discrepancies between recombination frequencies and physical distances in aspergillus nidulans: implications for gene identification.a rapid route to gene molecular identification involves using recombination frequencies in locating mutational sequence changes. we describe a case where the recombination frequency is deceptively low, probably reflecting centromere proximity. recombination frequencies are greatly reduced near the centromeres on the right arms of chromosomes iii and iv of aspergillus nidulans.200516020782
autoregulated, bidirectional and multicistronic gas-inducible mammalian as well as lentiviral expression vectors.we present a novel set of autoregulated, bidirectional and multicistronic mammalian as well as lentiviral expression vectors which enable transgene expression fine-tuning by gaseous acetaldehyde. the acetaldehyde-inducible regulation (air) technology capitalizes on aspergillus nidulans components evolved to convert ethanol into metabolic energy. air is based on functional interaction of the fungal transactivator alcr and alcr-specific chimeric promoters (p(air)) which drive desired transgene exp ...200516026881
biodegradation study of crop residues as affected by exogenous inorganic nitrogen and fungal inoculants.the comparative decomposition of chickpea residue, and chopped and unchopped wheat straw was investigated in pits for 120 days. microbial biomass, humus, c/n ratio, ph, electrical conductivity (ec), dehydrogenase, alkaline phosphatase, cellulase, xylanase, total phenol and soluble protein were determined to assess their response to the addition of inorganic nitrogen and mixed fungal inoculum of aspergillus nidulans, phanerochaete chrysosporium and trichoderma viride. the evaluation of physico-ch ...200516028202
comparing artificial and natural selection in rate of adaptation to genetic stress in aspergillus an experimental study of adaptation to negative pleiotropic effects of a major fungicide resistance mutation in the filamentous fungus aspergillus nidulans we have investigated the relative effectiveness of artificial selection vs. natural selection on the rate of compensatory evolution. using mycelial growth rate as a fitness measure, artificial selection involved the weekly transfer of the fastest growing sector onto a fresh plate. natural selection was approximated by transferring random s ...200516033548
cloning and functional analysis of the orotidine-5'-phosphate decarboxylase gene (pbrura3) of the pathogenic fungus paracoccidioides brasiliensis.a genomic clone encoding the paracoccidioides brasiliensis orotidine monophosphate decarboxylase gene (pbrura3) was isolated by screening a subgenomic plasmid dna library of this fungus, using a pcr amplification product of the gene as a probe. sequence analysis revealed that the gene contains an open reading frame of 855 bp with a single intron (162 bp), and encodes a putative 285 amino acids polypeptide of estimated molecular weight 31.1 kda and isoelectric point 6.5. the deduced amino acid se ...200516034822
a c-terminal fragment of an intron-encoded maturase is sufficient for promoting group i intron i introns often encode proteins that catalyze site-specific dna hydrolysis. some of these proteins have acquired the ability to promote splicing of their cognate intron, but whether these two activities reside in different regions of the protein remains obscure. a crystal structure of i-anii, a dual function intron-encoded protein, has shown that the protein has two pseudo-symmetric domains of equal size. each domain contacts its dna substrate on either side of two cleavage sites. as a fir ...200515769873
genes of the thymidine salvage pathway: thymine-7-hydroxylase from a rhodotorula glutinis cdna library and iso-orotate decarboxylase from neurospora crassa.genes for two enzymes in the thymidine salvage pathway, thymine-7-hydroxylase (thase; official name thymine dioxygenase) and iso-orotate decarboxylase (idcase) have been isolated from fungal sources. thase was isolated from a rhodotorula glutinis cdna library using a degenerate oligonucleotide based on the published amino acid sequence. the coding sequence was transferred to an escherichia coli expression system, from which recombinant thase activity was measured using 14c-labeled thymine. the t ...200515794921
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
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
class i and class ii chitin synthases are involved in septum formation in the filamentous fungus aspergillus nidulans.the class ii and class i chitin synthases of the filamentous fungus aspergillus nidulans are encoded by chsa and chsc, respectively. previously, we presented several lines of evidence suggesting that chsa and chsc have overlapping functions in maintaining cell wall integrity. in order to determine the functions of these chitin synthases, we employed electron and fluorescence microscopy and investigated in detail the cell wall of a deltachsa deltachsc double mutant (deltaac mutant) along with the ...200515947204
multiple roles of a heterotrimeric g-protein gamma-subunit in governing growth and development of aspergillus nidulans.vegetative growth signaling in the filamentous fungus aspergillus nidulans is primarily mediated by the heterotrimeric g-protein composed of fada (g alpha), sfad (g beta), and a presumed g gamma. analysis of the a. nidulans genome identified a single gene named gpga encoding a putative g gamma-subunit. the predicted gpga protein consists of 90 amino acids showing 72% similarity with yeast ste18p. deletion (delta) of gpga resulted in restricted vegetative growth and lowered asexual sporulation. m ...200515944346
evolution of a large ribosomal rna multigene family in filamentous fungi: birth and death of a concerted evolution eukaryotes, the primary components of the ribosome are encoded by multicopy nuclear ribosomal rna (rrna) genes: 28/26s, 18s, 5.8s, and 5s. copies of these genes are typically localized within tandem arrays and homogenized within a genome. as a result, nuclear rrna gene families have become a paradigm of concerted evolution. in filamentous fungi of the subphylum pezizomycotina, 5s rrna genes exist as a large and dispersed multigene family, with between 50 and 100 copies per genome. to determin ...200515784739
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