TitleAbstractYear(sorted ascending)
transformation of fusarium oxysporum by particle bombardment and characterisation of the resulting transformants expressing a gfp transgene.fusarium is the causative agent of a variety of economically significant vascular wilt diseases of vegetables, flowers and field crops. the completion of the first fusarium genome and the availability of an est database now provides a platform for both forward and reverse genetic approaches to ascribe gene function in this phytopathogen. to underpin these strategies effective gene transfer procedures will be required. here we describe an efficient and robust procedure for fusarium oxysporum tran ...200415702267
regulation of penicillin biosynthesis in filamentous fungi.the beta-lactam antibiotic penicillin is one of the mainly used antibiotics for the therapy of infectious diseases. it is produced as end product by some filamentous fungi only, most notably by aspergillus (emericella) nidulans and penicillium chrysogenum. the penicillin biosynthesis is catalysed by three enzymes which are encoded by the following three genes: acva (pcbab), ipna (pcbc) and aata (pende). the genes are organised into a gene cluster. although the production of secondary metabolites ...200415719552
cloning and use of sc as homologous marker for aspergillus niger transformation.the sc sequence from aspergillus niger was cloned and developed into a homologous marker system for genetic transformation. the coding region of the sc gene amplified by pcr from the a. niger genome was provided with aspergillus nidulans expression signals (gpda promoter and trpc terminator). this chimeric construct was used to successfully transform a spontaneous sc- isolate of a. niger to prototrophy. the transformants analyzed by southern analysis showed integration of multiple copies of the ...200415722148
cofactor processing in galactose oxidase.go (galactose oxidase; e.c. is a monomeric 68 kda enzyme that contains a single copper ion and an amino acid-derived cofactor. the enzyme is produced by the filamentous fungus fusarium graminearum as an extracellular enzyme. the enzyme has been extensively studied by structural, spectroscopic, kinetic and mutational approaches that have provided insight into the catalytic mechanism of this radical enzyme. one of the most intriguing features of the enzyme is the post-translational genera ...200415777009
[fatal aspergillus nidulans pneumonia]. 200415777589
plasmid vectors for protein production, gene expression and molecular manipulations in aspergillus niger.we constructed three sets of plasmids for use in aspergillus niger. these plasmids were assembled using various combinations of a series of modular dna cassettes that included a selectable marker, pyrg, derived from aspergillus nidulans; two promoter regions for directing protein expression; a cassette derived from the ama1 replicator sequence to support autonomous replication; and a reporter gene based on the a. niger laca gene. one set included integrating and autonomously replicating plasmids ...200415848224
loss of heterozygosity by mitotic recombination in diploid strain of aspergillus nidulans in response to castor oil plant detergent.somatic recombination in heterozygous diploid cells may be a promotional agent of neoplasms by inducing homozygosity of defective genes. tumor suppressor genes may in this way be completely suppressed in recombinant cells. in this work, the genotoxic effects of detergent derived from the castor oil plant (ricinus communis) in heterozygous diploid cells of aspergillus nidulans are evaluated. previous studies have evaluated the application of this substance in endodontic treatments as an irrigatin ...200415744430
in silico reconstruction of nutrient-sensing signal transduction pathways in aspergillus nidulans.we report here probable nutrient-sensing signal transduction pathways in aspergillus nidulans, a model filamentous fungus, based on sequence homology studies with known saccharomyces cerevisiae and schizosaccharomyces pombe proteins. specifically, we identified a. nidulans homologs for yeast proteins involved in (1) filamentation-invasion, (2) camp-pka, (3) pheromone response, (4) cell integrity and (5) tor signaling pathways. we have also studied autophagy, one of the most important cellular re ...200415752076
penicillium chrysogenum glucose oxidase -- a study on its antifungal effects.purification and characterization of the high molecular mass candida albicans-killing protein secreted by penicillium chrysogenum.200415546411
a phylogenomic approach to reconstructing the diversification of serine proteases in fungi.using a phylogenomic approach with 10 fungi of very different virulence and habitat, we determined that there was substantial diversification of subtilase-type proteases early in ascomycete history (with subsequent loss in many lineages) but with no comparable diversification of trypsins. patterns of intron loss and the degree of divergence between paralogues demonstrated that the proliferation of proteinase k subtilases and subtilisin type subtilases seen in pathogenic ascomycetes (metarhizium ...200415525405
acfkh1, a novel member of the forkhead family, associates with the rfx transcription factor cpcr1 in the cephalosporin c-producing fungus acremonium the filamentous fungus acremonium chrysogenum, a complex regulatory network of transcription factors controls the expression of at least seven cephalosporin c biosynthesis genes. the rfx transcription factor cpcr1 binds to regulatory sequences in the promoter region of cephalosporin c biosynthesis genes, and is involved in the transcriptional regulation of the pcbc gene which encodes isopenicillin n synthase. in this study, we used cpcr1 in a yeast two-hybrid screen to identify potential prot ...200415527986
the fungal stre-element-binding protein seb1 is involved but not essential for glycerol dehydrogenase (gld1) gene expression and glycerol accumulation in trichoderma atroviride during osmotic stress.fungi counteract extracellular osmotic pressure by producing intracellular polyols to prevent loss of water. in yeast osmotic signaling involves a map-kinase pathway culminating at the stre-binding transcription factors msn2/4. we investigated the role of a putative stre-binding orthologue of trichoderma atroviride, seb1, in osmotic stress signaling. t. atroviride, subjected to osmotic stress (10% glucose or glycerol, 1m kcl or nacl), responds by raising its intracellular glycerol level. in cont ...200415531216
modulation of the ligand binding properties of the transcription repressor nmra by gata-containing dna and site-directed mutagenesis.nmra is a negative transcription-regulating protein that binds to the c-terminal region of the gata transcription-activating protein area. the proposed molecular mechanism of action for nmra is to inhibit area binding to its target promoters. in contrast to this proposal, we report that a c-terminal fragment of area can bind individually to gata-containing dna and nmra and that in the presence of a mixture of gata-containing dna and nmra, the area fragment binds preferentially to the gata-contai ...200415537757
endogenous lipogenic regulators of spore balance in aspergillus nidulans.the ability of fungi to produce both meiospores and mitospores has provided adaptive advantages in survival and dispersal of these organisms. here we provide evidence of an endogenous mechanism that balances meiospore and mitospore production in the model filamentous fungus aspergillus nidulans. we have discovered a putative dioxygenase, ppoc, that functions in association with a previously characterized dioxygenase, ppoa, to integrate fatty acid derived oxylipin and spore production. in contras ...200415590815
fostua, encoding a basic helix-loop-helix protein, differentially regulates development of three kinds of asexual spores, macroconidia, microconidia, and chlamydospores, in the fungal plant pathogen fusarium oxysporum.the soil-borne fungus fusarium oxysporum causes vascular wilt of a wide variety of plant species. f. oxysporum produces three kinds of asexual spores, macroconidia, microconidia, and chlamydospores. falcate macroconidia are formed generally from terminal phialides on conidiophores and rarely from intercalary phialides on hyphae. ellipsoidal microconidia are formed from intercalary phialides on hyphae. globose chlamydospores with thick walls are developed by the modification of hyphal and conidia ...200415590816
potential link between the nima mitotic kinase and nuclear membrane fission during mitotic exit in aspergillus nidulans.we have isolated tinc as a nima-interacting protein by using the yeast two-hybrid system and have confirmed that tinc interacts with nima in aspergillus nidulans. the tinc-nima interaction is stabilized in the absence of phosphatase inhibitors and in the presence of kinase-inactive nima, suggesting that the interaction is enhanced when nima is not fully activated. tinc is a cytoplasmic protein. tinc homologues and a tinc-like protein (a. nidulans hetc) are conserved in other filamentous fungi. n ...200415590818
combining transcriptome data with genomic and cdna sequence alignments to make confident functional assignments for aspergillus nidulans genes.whole genome sequencing of several filamentous ascomycetes is complete or in progress; these species, such as aspergillus nidulans, are relatives of saccharomyces cerevisiae. however, their genomes are much larger and their gene structure more complex, with genes often containing multiple introns. automated annotation programs can quickly identify open reading frames for hypothetical genes, many of which will be conserved across large evolutionary distances, but further information is required t ...200415449589
[rgs proteins (regulators of g protein signaling) and their roles in regulation of immune response].rgs proteins (regulators of g-protein signaling) comprise a protein family responsible for regulating g proteins. by enhancing the gtpase activity of the a subunit, they speed up the reconstruction of the heterotrimeric structure of g protein, thus inhibiting its signal transduction. sst2 protein in yeast saccharomyces cervisiae, flba in fungus aspergillus nidulans, and egl-10 in the nematode caenorhabditis elegans are the first native g regulators with gtpase activity (gaps:--gtpase-activating ...200415459549
comparison of ligand-induced conformational changes and domain closure mechanisms, between prokaryotic and eukaryotic dehydroquinate synthases.dehydroquinate synthase (dhqs) is a potential target for the development of novel broad-spectrum antimicrobial drugs, active against both prokaryotes and lower eukaryotes. structures have been reported for aspergillus nidulans dhqs (andhqs) in complexes with a range of ligands. analysis of these andhqs structures showed that a large-scale domain movement occurs during the normal catalytic cycle, with a complex series of structural elements propagating substrate binding-induced conformational cha ...200415465043
double-joint pcr: a pcr-based molecular tool for gene manipulations in filamentous fungi.gene replacement via homologous double crossover in filamentous fungi requires relatively long (preferentially >0.5 kb) flanking regions of the target gene. for this reason, gene replacement cassettes are usually constructed through multiple cloning steps. to facilitate gene function studies in filamentous fungi avoiding tedious cloning steps, we have developed a pcr-assisted dna assembly procedure and applied it to delete genes in filamentous fungi. while the principle of this procedure is esse ...200415465386
identification and complementation of abnormal hyphal branch mutants ahba1 and ahbb1 in aspergillus nidulans.branching generates new axes of polar growth in filamentous fungi and is critical for development, reproduction, and pathogenicity. to investigate branching we screened an aspergillus nidulans temperature-sensitive mutant collection for abnormal hyphal branch (ahb) mutants. we identified two mutants, ahba1, which showed reduced branching relative to wild type at restrictive temperature, and ahbb1, which showed increased branching relative to wild type at restrictive temperature. both mutants als ...200415465388
the aspergillus fumigatus cell wall is organized in domains that are remodelled during polarity establishment.aspergillus fumigatus is a life-threatening and increasingly frequent pathogen of the immunocompromised. like other filamentous fungi a. fumigatus grows in a highly polar manner, adding new cell wall to the apical region of hyphae. mabs were raised against isolated a. fumigatus cell walls. fifteen antibodies bound reproducibly to isolated cell walls in elisas and to the walls of intact cells in immunofluorescence experiments. surprisingly, individual mabs showed distinct patterns of localization ...200415470106
introns and splicing elements of five diverse fungi.genomic sequences and expressed sequence tag data for a diverse group of fungi (saccharomyces cerevisiae, schizosaccharomyces pombe, aspergillus nidulans, neurospora crassa, and cryptococcus neoformans) provided the opportunity to accurately characterize conserved intronic elements. an examination of large intron data sets revealed that fungal introns in general are short, that 98% or more of them belong to the canonical splice site (ss) class (5'gu...ag3'), and that they have polypyrimidine tra ...200415470237
rapid production of gene replacement constructs and generation of a green fluorescent protein-tagged centromeric marker in aspergillus nidulans.a method to rapidly generate gene replacement constructs by fusion pcr is described for aspergillus nidulans. the utility of the approach is demonstrated by green fluorescent protein (gfp) tagging of a. nidulans ndc80 to visualize centromeres through the cell cycle. the methodology makes possible large-scale gfp tagging, promoter swapping, and deletion analysis of a. nidulans.200415470263
recent advances in the characterization of ambient ph regulation of gene expression in filamentous fungi and yeasts.all microorganisms must adapt to the ph of their environment. one aspect of this adaptation, particularly important for organisms that grow over a wide ph range, is the ability to express appropriately genes whose roles ultimately involve functions at the cell surface or in the environment. genes encoding permeases, secreted enzymes, enzymes involved in synthesis of exported metabolites such as toxins and antibiotics, and probably enzymes modifying secreted proteins posttranslationally all fall ...200415487944
gas-inducible transgene expression in mammalian cells and mice.we describe the design and detailed characterization of a gas-inducible transgene control system functional in different mammalian cells, mice and prototype biopharmaceutical manufacturing. the acetaldehyde-inducible alcr-p(alca) transactivator-promoter interaction of the aspergillus nidulans ethanol-catabolizing regulon was engineered for gas-adjustable transgene expression in mammalian cells. fungal alcr retained its transactivation characteristics in a variety of mammalian cell lines and reve ...200415502819
synthesis and antimicrobial activity of some netropsin analogues.nine novel lexitropsins were synthesized by linking two netropsin-like moieties through three different dicarboxylic acids; 9,10-dihydro-2,7-phenanthrenedicarboxylic acid; [(3-[[(carboxymethyl)amino]carbonyl]benzoyl)amino]acetic acid and indole-2,5-dicarboxylic acid. the netropsin residues were modified by the use of n-isopentylpyrrole, 5-methylthiophene or 5-isopropylthiazole heterocyclic building blocks in place of the usual n-methylpyrrole. the compounds were tested against five gram-positive ...200415505717
connection of propionyl-coa metabolism to polyketide biosynthesis in aspergillus nidulans.propionyl-coa is an intermediate metabolite produced through a variety of pathways including thioesterification of propionate and catabolism of odd chain fatty acids and select amino acids. previously, we found that disruption of the methylcitrate synthase gene, mcsa, which blocks propionyl-coa utilization, as well as growth on propionate impaired production of several polyketides-molecules typically derived from acetyl-coa and malonyl-coa-including sterigmatocystin (st), a potent carcinogen, an ...200415514053
[antibiotic properties of some species of genus aspergillus mich].antibiotic activity screening of some species of genus aspergillus (64 strains) to different test-organisms (gram positive, gram negative, phytopathogenic bacteria and yeasts) has been carried out. the researched strains a. parvulus, a. ochraceus, a. ustus, a. versicolor, a.fumigatus, a. niger, a. deflectus, a. clavatus were characterized by a wide spectrum of antibiotic activity; the strains a. flavipes, a. sydowii, a. terreus, a. flavus, a. nidulans, a. alliaceus, a. fluticulosus were characte ...200415515902
tama interacts with leub, the homologue of saccharomyces cerevisiae leu3p, to regulate gdha expression in aspergillus nidulans.previous studies have shown that expression of the gdha gene, encoding nadp-linked glutamate dehydrogenase (nadp-gdh), in aspergillus nidulans is regulated by the major nitrogen regulatory protein area and its co-activator tama. we show here that loss of tama function has a more severe effect on the levels of gdha expression than loss of area function. using tama as the bait in a yeast two-hybrid screen, we have identified a second protein that interacts with tama. sequencing analysis and functi ...200415517391
regulation of aflatoxin synthesis by fada/camp/protein kinase a signaling in aspergillus parasiticus.analysis of fada and pkaa mutants in the filamentous fungus aspergillus nidulans demonstrated that fada (galpha) stimulates cyclic amp (camp)-dependent protein kinase a (pka) activity resulting, at least in part, in inhibition of conidiation and sterigmatocystin (st) biosynthesis. in contrast, camp added to the growth medium stimulates aflatoxin (af) synthesis in aspergillus parasiticus. our goal was to explain these conflicting reports and to provide mechanistic detail on the role of fada, camp ...200415518351
mesa, a novel fungal protein required for the stabilization of polarity axes in aspergillus nidulans.the aspergillus nidulans proteome possesses a single formin, sepa, which is required for actin ring formation at septation sites and also plays a role in polarized morphogenesis. previous observations imply that complex regulatory mechanisms control the function of sepa and ensure its correct localization within hyphal tip cells. to characterize these mechanisms, we undertook a screen for mutations that enhance sepa defects. of the mutants recovered, mesa1 causes the most dramatic defect in pola ...200415155805
crea-mediated carbon catabolite repression of beta-galactosidase formation in aspergillus nidulans is growth rate dependent.carbon catabolite repression by the crea-transcriptional repressor is widespread in filamentous fungi, but the mechanism by which glucose triggers carbon catabolite repression is still poorly understood. we investigated the hypothesis that the growth rate on glucose may control crea-dependent carbon catabolite repression by using glucose-limited chemostat cultures and the intracellular beta-galactosidase activity of aspergillus nidulans, which is repressed by glucose, as a model system. chemosta ...200415158274
altering a gene involved in nuclear distribution increases the repeat-induced point mutation process in the fungus podospora anserina.repeat-induced point mutation (rip) is a homology-dependent gene-silencing mechanism that introduces c:g-to-t:a transitions in duplicated dna segments. cis-duplicated sequences can also be affected by another mechanism called premeiotic recombination (pr). both are active over the sexual cycle of some filamentous fungi, e.g., neurospora crassa and podospora anserina. during the sexual cycle, several developmental steps require precise nuclear movement and positioning, but connections between rip ...200415166143
streptomyces lividans and brevibacterium lactofermentum as heterologous hosts for the production of x22 xylanase from aspergillus nidulans.the aspergillus nidulans gene xlna coding for the fungal xylanase x22 has been cloned and expressed in two heterologous bacterial hosts: streptomyces lividans and brevibacterium lactofermentum. streptomyces strains yielded 10 units/ml of xylanase when the protein was produced with its own signal peptide, and 19 units/ml when its signal peptide was replaced by the one for xylanase xys1 from streptomyces halstedii. b. lactofermentum was also able to produce xylanase x22, affording 6 units/ml upon ...200415168093
pina is essential for growth and positively influences nima function in aspergillus nidulans.the phospho-ser/thr-directed prolyl-isomerase pin1 was originally identified in vertebrate systems as a negative regulator of nima, a ser/thr protein kinase that regulates the g(2)/m transition in aspergillus nidulans. here we explore the physiological roles of the pin1 orthologue, pina, in a. nidulans and evaluate the relevance of the interaction of pina with nima in this fungus. we find pina to be an essential gene in a. nidulans. in addition, when pina levels are reduced 50-fold the cells gro ...200415178679
the dual nature of the wheat xylanase protein inhibitor xip-i: structural basis for the inhibition of family 10 and family 11 xylanases.the xylanase inhibitor protein i (xip-i) from wheat triticum aestivum is the prototype of a novel class of cereal protein inhibitors that inhibit fungal xylanases belonging to glycoside hydrolase families 10 (gh10) and 11 (gh11). the crystal structures of xip-i in complex with aspergillus nidulans (gh10) and penicillium funiculosum (gh11) xylanases have been solved at 1.7 and 2.5 a resolution, respectively. the inhibition strategy is novel because xip-i possesses two independent enzyme-binding s ...200415181003
fungal metabolic model for type i 3-methylglutaconic aciduria.aspergillus nidulans catabolizes leu to acetyl-coa and acetoacetate through a pathway homologous to that used by humans. fungal hlya encodes a bifunctional polypeptide comprising the last two enzymes in this pathway, 3-methylglutaconyl-coa hydratase and 3-hydroxy-3-methylglutaryl-coa lyase. hlya transcription is specifically induced by leu. a delta hlya mutation removing the complete 3-methylglutaconyl-coa hydratase c-terminal domain prevents growth on leu but not on lactose or other amino acids ...200415181004
molecular characterization of protein o-mannosyltransferase and its involvement in cell-wall synthesis in aspergillus nidulans.protein o-glycosylation is essential for protein modification and plays important roles in eukaryotic cells. o-mannosylation of proteins occurs in the filamentous fungus aspergillus. the structure and function of the pmta gene, encoding protein o-d-mannosyltransferase, which is responsible for the initial o-mannosylation reaction in aspergillus nidulans, was characterized. disruption of the pmta gene resulted in the reduction of in vitro protein o-d-mannosyltransferase activity to 6 % of that of ...200415184583
the kip3-like kinesin kipb moves along microtubules and determines spindle position during synchronized mitoses in aspergillus nidulans hyphae.kinesins are motor proteins which are classified into 11 different families. we identified 11 kinesin-like proteins in the genome of the filamentous fungus aspergillus nidulans. relatedness analyses based on the motor domains grouped them into nine families. in this paper, we characterize kipb as a member of the kip3 family of microtubule depolymerases. the closest homologues of kipb are saccharomyces cerevisiae kip3 and schizosaccharomyces pombe klp5 and klp6, but sequence similarities outside ...200415189985
candida albicans rim13p, a protease required for rim101p processing at acidic and alkaline phs.candida albicans is an important commensal of mucosal surfaces that is also an opportunistic pathogen. this organism colonizes a wide range of host sites that differ in ph; thus, it must respond appropriately to this environmental stress to survive. the ability to respond to neutral-to-alkaline phs is governed in part by the rim101 signal transduction pathway. here we describe the analysis of c. albicans rim13p, a homolog of the rim13p/palb calpain-like protease member of the rim101/pacc pathway ...200415189995
successful elimination of an invasive aspergillus nidulans lung infection by voriconazole after failure of a combination of caspofungin and liposomal amphotericin b in a boy with chronic granulomatous disease.chronic granulomatous disease is an inherited defect in host defense mechanisms mainly affecting neutrophil function. pulmonary infection with aspergillus nidulans in a child with chronic granulomatous disease could not be eliminated by a combination of caspofungin and liposomal amphotericin b. voriconazole was successful in clearing the infection.200415194848
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 ...200415208636
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 ...200415228532
tangled nudels? 200415232582
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 ...200415234517
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 ...200415236494
ph control of the production of recombinant glucose oxidase in aspergillus nidulans.recombinant aspergillus nidulans sval040, capable of synthesizing and secreting glucose oxidase derived from aspergillus niger was used to study the influence of ph and carbon source on enzyme production.200415239699
the pho80-like cyclin of aspergillus nidulans regulates development independently of its role in phosphate saccharomyces cerevisiae, phosphate acquisition enzymes are regulated by a cyclin-dependent kinase (pho85), a cyclin (pho80), the cyclin-dependent kinase inhibitor pho81, and the helix-loop-helix transcription factor pho4 (the pho system). previous studies in aspergillus nidulans indicate that a pho85-like kinase, phoa, does not regulate the classic pho system but regulates development in a phosphate-dependent manner. a pho80-like cyclin has now been isolated through its interaction with phoa ...200415247298
a role for cred, a carbon catabolite repression gene from aspergillus nidulans, in aspergillus nidulans, it is known that creb encodes a deubiquitinating enzyme that forms a complex with the wd40 motif containing protein encoded by crec, that mutations in these genes lead to altered carbon source utilization and that the cred34 mutation suppresses the phenotypic effects of mutations in crec and creb. therefore, cred was characterized in order to dissect the regulatory network that involves the creb-crec deubiquitination complex. cred contains arrestin domains and py motifs ...200415255903
physiological and morphological changes in autolyzing aspergillus nidulans cultures.physiological and morphological changes in carbon-limited autolyzing cultures of aspergillus nidulans were described. the carbon starvation arrested conidiation while the formation of filamentous and "yeast-like" hyphal fragments with profoundly altered metabolism enabled the fungus to survive the nutritional stress. the morphological and physiological stress responses, which maintained the cellular integrity of surviving hyphal fragments at the expense of autolyzing cells, were highly concerted ...200415259768
on the mechanism of action of the antifungal agent propionate.propionate is used to protect bread and animal feed from moulds. the mode of action of this short-chain fatty acid was studied using aspergillus nidulans as a model organism. the filamentous fungus is able to grow slowly on propionate, which is oxidized to acetyl-coa via propionyl-coa, methylcitrate and pyruvate. propionate inhibits growth of a. nidulans on glucose but not on acetate; the latter was shown to inhibit propionate oxidation. when grown on glucose a methylcitrate synthase deletion mu ...200415265042
the ganb galpha-protein negatively regulates asexual sporulation and plays a positive role in conidial germination in aspergillus nidulans.we isolated the ganb gene encoding the galpha-protein homolog from aspergillus nidulans. to investigate the cellular function of ganb, various mutant strains were isolated. deletion of constitutively inactive ganb mutants showed conidiation and derepressed brla expression in a submerged culture. constitutive activation of ganb caused a reduction in hyphal growth and a severe defect in asexual sporulation. we therefore propose that ganb may negatively regulate asexual sporulation through the brla ...200415280244
molecular cloning and characterization of a cdna encoding the n-acetyl-beta-d-glucosaminidase homologue of paracoccidioides brasiliensis.a cdna encoding the n-acetyl-beta-d-glucosaminidase (nag) protein of paracoccidioides brasiliensis, pb nag1, was cloned and characterized. the 2663-nucleotide sequence of the cdna consisted of a single open reading frame encoding a protein with a predicted molecular mass of 64.73 kda and an isoeletric point of 6.35. the predicted protein includes a putative 30-amino-acid signal peptide. the protein as a whole shares considerable sequence similarity with 'classic' nag. the primary sequence of pb ...200415283239
vea is required for toxin and sclerotial production in aspergillus was long been noted that secondary metabolism is associated with fungal development. in aspergillus nidulans, conidiation and mycotoxin production are linked by a g protein signaling pathway. also in a. nidulans, cleistothecial development and mycotoxin production are controlled by a gene called vea. here we report the characterization of a vea ortholog in the aflatoxin-producing fungus a. parasiticus. cleistothecia are not produced by aspergillus parasiticus; instead, this fungus produces sp ...200415294809
rapid differentiation of aspergillus species from other medically important opportunistic molds and yeasts by pcr-enzyme immunoassay.we developed a pcr-based assay to differentiate medically important species of aspergillus from one another and from other opportunistic molds and yeasts by employing universal, fungus-specific primers and dna probes in an enzyme immunoassay format (pcr-eia). oligonucleotide probes, directed to the internal transcribed spacer 2 region of ribosomal dna from aspergillus flavus, aspergillus fumigatus, aspergillus nidulans, aspergillus niger, aspergillus terreus, aspergillus ustus, and aspergillus v ...200415297489
the metarhizium anisopliae trp1 gene: cloning and regulatory analysis.the trp1 gene from the entomopathogenic fungus metarhizium anisopliae, cloned by heterologous hybridization with the plasmid carrying the trpc gene from aspergillus nidulans, was sequence characterized. the predicted translation product has the conserved catalytic domains of glutamine amidotransferase (g domain), indoleglycerolphosphate synthase (c domain), and phosphoribosyl anthranilate isomerase (f domain) organized as nh2-g-c-f-cooh. the orf is interrupted by a single intron of 60 nt that is ...200415297933
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 ...200415300480
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 ...200415302831
prp8 intein in fungal pathogens: target for potential antifungal drugs.inteins are self-splicing intervening sequences in proteins, and inteins of pathogenic organisms can be attractive drug targets. here, we report an intein in important fungal pathogens including aspergillus fumigatus, aspergillus nidulans, histoplasma capsulatum, and different serotypes of cryptococcus neoformans. this intein is inside the extremely conserved and functionally essential prp8 protein, and it varies in size from 170 aa in c. neoformans to 819 aa in a. fumigatus, which is caused by ...200415304322
effect of vitamin e on autolysis and sporulation of aspergillus nidulans.the morphologic and physiologic effects of vitamin e, a powerful antioxidant, on the autolysis and sporulation of aspergillus nidulans fgsc26 were studied. in carbon-depleted submerged cultures, reactive oxygen species (ros) accumulated in the cells and, concomitantly, progressing autolysis was observed, which was characterized by decreasing dry cell masses and pellet diameters as well as by increasing extracellular chitinase activities. vitamin e supplemented at a concentration of 1 g/l hindere ...200415304761
influence of fadag203r and deltaflba mutations on morphology and physiology of submerged aspergillus nidulans cultures.morphologic and physiologic changes taking place in carbon-limited submerged cultures of aspergillus nidulans deltaflba and fadag203r strains were studied. loss-of-function mutation of the flba gene resulted in an altered germination with unusually thick germination tubes, "fluffy" pellet morphology, as well as a reduced fragmentation rate of hyphae during autolysis. in the fadag203r mutant strain, conidiophores formed in the stationary phase of growth, and the size of pellets shrank considerabl ...200415304762
histone methyltransferases in aspergillus nidulans: evidence for a novel enzyme with a unique substrate specificity.we have studied enzymes involved in histone arginine methylation in the filamentous fungus aspergillus nidulans. three distinct protein arginine methyltransferases (prmts) could be identified, which all exhibit intrinsic histone methyltransferase activity when expressed as glutathione s-transferase (gst) fusion proteins. two of these proteins, termed rmta (arginine methyltransferase a) and rmtc, reveal significant sequence homology to the well-characterized human proteins prmt1 and prmt5, respec ...200415311944
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 ...200415322347
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 ...200415324811
a single subunit of a heterotrimeric ccaat-binding complex carries a nuclear localization signal: piggy back transport of the pre-assembled complex to the 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 ...200415327951
identification and characterization of a novel delta12-fatty acid desaturase gene from rhizopus arrhizus.based on the sequence information of delta12-fatty acid desaturase genes (from mucor circinelloides, mortierella alpina, mucor rouxii and aspergillus nidulans), which were involved in the conversion from c18:1 to c18:2, a cdna sequence putatively encoding a delta12-fatty acid desaturase was isolated from rhizopus arrhizus using the combination of reverse transcription-polymerase chain reaction (rt-pcr) and rapid amplification of cdna ends (race) methods. sequence analysis indicated that it had a ...200415327973
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 ...200415328121
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 ...200415341643
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 ...200415342504
characterization of the aspergillus parasiticus delta12-desaturase gene: a role for lipid metabolism in the aspergillus-seed 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 ...200415347747
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 ...200415364940
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 ...200415375695
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 ...200415378266
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 ...200415379642
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 " ...200415381397
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 ...200415386109
gamma-tubulin plays an essential role in the coordination of mitotic events.recent data from multiple organisms indicate that gamma-tubulin has essential, but incompletely defined, functions in addition to nucleating microtubule assembly. to investigate these functions, we examined the phenotype of mipad159, a cold-sensitive allele of the gamma-tubulin gene of aspergillus nidulans. immunofluorescence microscopy of synchronized material revealed that at a restrictive temperature mipad159 does not inhibit mitotic spindle formation. anaphase a was inhibited in many nuclei, ...200414668489
aspergillus nidulans rhoa is involved in polar growth, branching, and cell wall synthesis.growth of the filamentous fungus aspergillus nidulans begins when the conidium breaks dormancy and grows isotropically. eventually a germ tube emerges and the axis of growth remains fixed in the primary hypha while new growth axes are established basally to form secondary germ tubes and lateral branches. rho1 is a rho family gtpase that has been shown to be involved in polarity establishment and cell wall deposition in saccharomyces cerevisiae. a gene predicted to encode a rho1 homolog was clone ...200414643255
ammonium-induced internalisation of uapc, the general purine permease from aspergillus nidulans.the aspergillus nidulans uapc protein is a high-affinity, moderate-capacity, uric acid-xanthine transporter, which also displays a low transport capacity for hypoxanthine, adenine, and guanine. it has been previously shown that a functional uapc-gfp fusion protein localises at the plasma membrane. here, we demonstrate that ammonium, a preferred nitrogen source, dramatically changes the subcellular distribution of uapc. after addition of ammonium, uapc-gfp is removed from the plasma membrane and ...200414643258
aspergillus nidulans hypa regulates morphogenesis through the secretion pathway.aspergillus nidulans hypa encodes a predicted 1474 amino acid, 161.9 kda cytoplasmic peptide. strains with hypa1 and hypa6 alleles are wild type at 28 degrees c but have wide, slow-growing hyphae and thick walls at 42 degrees c. hypa1 and hypa6 have identical genetic lesions. hypa1 and hypa6 restrictive phenotypes have statistically similar morphometry, and strains with either allele can conidiate at 42 degrees c. hypa deletion strains require osmotic support and have aberrant morphology, but pr ...200414643261
fungal metabolic model for 3-methylcrotonyl-coa carboxylase deficiency.aspergillus nidulans is able to use leu as the sole carbon source through a metabolic pathway leading to acetyl-coa and acetoacetate that is homologous to that used by humans. mcca and mccb, the genes encoding the subunits of 3-methylcrotonyl-coa carboxylase, are clustered with ivda encoding isovaleryl-coa dehydrogenase, a third gene of the leu catabolic pathway, on the left arm of chromosome iii. their transcription is induced by leu and other hydrophobic amino acids and repressed by glucose. p ...200414612443
high efficiency transformation of penicillium nalgiovense with integrative and autonomously replicating plasmids.penicillium nalgiovense is a filamentous fungus that is acquiring increasing biotechnological importance in the food industry due to its widespread use as starter culture for cured and fermented meat products. strains of p. nalgiovense can be improved by genetic modification to remove the production of penicillin and other potentially hazardous secondary metabolites, to improve its capacity to control the growth of undesirable fungi and bacteria on the meat product, and other factors that contri ...200414698104
the lipid body protein, ppoa, coordinates sexual and asexual sporulation in aspergillus nidulans.the coexistence of sexual and asexual reproductive cycles within the same individual is a striking phenomenon in numerous fungi. in the fungus aspergillus nidulans (teleomorph: emericella nidulans) endogenous oxylipins, called psi factor, serve as hormone-like signals that modulate the timing and balance between sexual and asexual spore development. here, we report the identification of a. nidulans ppoa, encoding a putative fatty acid dioxygenase, involved in the biosynthesis of the linoleic aci ...200414699095
the lis1-related protein nudf of aspergillus nidulans and its interaction partner nude bind directly to specific subunits of dynein and dynactin and to alpha- and gamma-tubulin. 200414712821
nuclear import of yeast gcn4p requires karyopherins srp1p and kap95p.the yeast transcription factor gcn4p contains two stretches of amino acid residues, nls1 and nls2, which are independently able to relocate the cytoplasmic protein chorismate mutase into the nucleus. only nls2 is conserved among fungi. a truncated version of cpca (the counterpart of gcn4p in aspergillus nidulans), which lacks the conserved nls, accumulates in the cytoplasm instead of the nucleus. nuclear uptake mediated by the nls1 of gcn4p is impaired by defects in genes for several different k ...200414648200
the pot1+ homologue in aspergillus nidulans is required for ordering mitotic events.orderly progression through mitosis is essential to reduce segregation errors in the cell's genetic material. we have used a cytological screen to identify a mutant that progresses through mitosis aberrantly and have cloned the complementing gene, nimu, which encodes a protein related to pot1 and other telomere end-binding proteins. we show that loss of nimu function leads to premature mitotic spindle elongation, premature mitotic exit, errors in chromosome segregation, and failure to delay mito ...200414657278
the alternative d-galactose degrading pathway of aspergillus nidulans proceeds via l-sorbose.the catabolism of d-galactose in yeast depends on the enzymes of the leloir pathway. in contrast, aspergillus nidulans mutants in galactokinase ( gale) can still grow on d-galactose in the presence of ammonium-but not nitrate-ions as nitrogen source. a. nidulans gale mutants transiently accumulate high (400 mm) intracellular concentrations of galactitol, indicating that the alternative d-galactose degrading pathway may proceed via this intermediate. the enzyme degrading galactitol was identified ...200414624333
aspergillus fumigatus rasa and rasb regulate the timing and morphology of asexual development.expression of rasa plays an important role in conidial germination in aspergillus nidulans. conidial germination is required to initiate both infection and asexual development in the opportunistic pathogen aspergillus fumigatus. therefore, we sought to determine the requirements for ras proteins in conidial germination and asexual development of a. fumigatus. a second homolog, rasb, has been identified that characterizes a new subclass of ras genes. dominant active (da) and dominant negative (dn ...200414732259
a putative high affinity hexose transporter, hxta, of aspergillus nidulans is induced in vegetative hyphae upon starvation and in ascogenous hyphae during cleistothecium formation.fungi employ different carbohydrate uptake systems to adapt to certain environmental conditions and to different carbon source concentrations. the hydrolysis of polymeric carbohydrates and the subsequent uptake of monomeric forms may also play a role in development. aspergillus nidulans accumulates cell wall components during vegetative growth and degrades them during sexual development. we have identified the hxta (high affinity hexose transporter) gene in a differential library, which was enri ...200414732261
selection arena in aspergillus nidulans.the selection arena hypothesis states that overproduction of zygotes--a widespread phenomenon in animals and plants--can be explained as a mechanism of progeny choice. as a similar mechanism, the ascomycetous fungus aspergillus nidulans may overproduce dikaryotic fruit initials, hereafter called dikaryons. then, progeny choice might involve selection on which of these dikaryons will thrive to produce thousands of zygotes. these zygotes each produce eight sexual spores which together fill up one ...200414732264
use of expressed sequence tag analysis and cdna microarrays of the filamentous fungus aspergillus nidulans.the use of microarrays in the analysis of gene expression is becoming widespread for many organisms, including yeast. however, although the genomes of a number of filamentous fungi have been fully or partially sequenced, microarray analysis is still in its infancy in these organisms. here, we describe the construction and validation of microarrays for the fungus aspergillus nidulans using pcr products from a 4092 est conidial germination library. an experiment was designed to validate these arra ...200414732266
novel effect of voriconazole on conidiation of aspergillus species.our previous studies of aspergillus fumigatus showed that colonies that grew in the presence of voriconazole (vcz) were characteristically white without pigmentation. we therefore investigated the effect of various triazoles on conidiation and pigmentation in four commonly isolated aspergillus species and the results were compared with those obtained for polyene and echinocandin classes of antifungal drugs. aspergillus cultures were grown on sabouraud dextrose agar containing subinhibitory conce ...200414732317
osteomyelitis due to aspergillus spp. in patients with chronic granulomatous disease: comparison of aspergillus nidulans and aspergillus fumigatus.chronic granulomatous disease (cgd) is a rare inherited disorder of nadph oxidase in which phagocytes fail to generate reactive antimicrobial oxidants. invasive fungal infections are an important cause of morbidity and mortality in cgd patients, with aspergillus spp. being the most frequent fungal pathogens. we reviewed the reported cases of osteomyelitis in cgd patients due to aspergillus nidulans and compared them with those due to aspergillus fumigatus.200414732328
meab is a component of the methylmalonyl-coa mutase complex required for protection of the enzyme from inactivation.adenosylcobalamin-dependent methylmalonyl-coa mutase catalyzes the interconversion of methylmalonyl-coa and succinyl-coa. in humans, deficiencies in the mutase lead to methylmalonic aciduria, a rare disease that is fatal in the first year of life. such inherited deficiencies can result from mutations in the mutase structural gene or from mutations that impair the acquisition of cobalamins. recently, a human gene of unknown function, mmaa, has been implicated in methylmalonic aciduria (dobson, c. ...200414734568
negative selection using thymidine kinase increases the efficiency of recovery of transformants with targeted genes in the filamentous fungus leptosphaeria maculans.a vector system was constructed that is designed to decrease the number of transformants required to be screened when looking for gene disruption events in filamentous fungi. this vector was used to mutate two genes, an atp-binding cassette transporter ( lmabct4) and a two-component histidine kinase gene ( lmhk1) in the ascomycete leptosphaeria maculans. the system uses the thymidine kinase gene from the herpes simplex virus as a negative selectable marker. thymidine kinase expression is regulat ...200414749893
mate transposable elements in aspergillus nidulans: evidence of repeat-induced point mutation.the sequences of five mate transposable elements were retrieved from the aspergillus nidulans genome sequence. these elements are 6.1 kb in length and are characterized by 9-10 bp target site duplications, paired approximately 40 bp palindromes close to each end, and in the unmutated elements, 57 clustered spe-motifs (rwctagwy) scattered through their length. short open reading frames have no known homology. two of the mate elements have numerous c --> t transitions on both dna strands relative ...200414761791
activation of caspase-like activity and poly (adp-ribose) polymerase degradation during sporulation in aspergillus nidulans.mycelium vacuolization, protein degradation, and as the final stage autolysis, often accompanies developmental changes in fungi and similarities between autolysis and apoptosis have previously been suggested. caspases are the key executors of apoptosis and in this study caspase-like activities were detected in protein extracts from aspergillus nidulans during sporulation. this was shown by hydrolysis of the fluorescent devd- and ietd-afc peptide substrates specific for caspase 3- and 8-like acti ...200414761796
chromatin rearrangements in the prnd-prnb bidirectional promoter: dependence on transcription factors.the prnd-prnb intergenic region regulates the divergent transcription of the genes encoding proline oxidase and the major proline transporter. eight nucleosomes are positioned in this region. upon induction, the positioning of these nucleosomes is lost. this process depends on the specific transcriptional activator prna but not on the general gata factor area. induction of prnb but not prnd can be elicited by amino acid starvation. a specific nucleosomal pattern in the prnb proximal region is as ...200414871945
aspergillus niger msta encodes a high-affinity sugar/h+ symporter which is regulated in response to extracellular ph.a sugar-transporter-encoding gene, msta, which is a member of the major facilitator superfamily, has been cloned from a genomic dna library of the filamentous fungus aspergillus niger. to enable the functional characterization of msta, a full-length cdna was expressed in a saccharomyces cerevisiae strain deficient in hexose uptake. uptake experiments using 14c-labelled monosaccharides demonstrated that although able to transport d-fructose ( k(m), 4.5+/-1.0 mm), d-xylose ( k(m), 0.3+/-0.1 mm) an ...200414717659
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