Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| secondary chemicals protect mould from fungivory. | the vast repertoire of toxic fungal secondary metabolites has long been assumed to have an evolved protective role against fungivory. it still remains elusive, however, whether fungi contain these compounds as an anti-predator adaptation. we demonstrate that loss of secondary metabolites in the soil mould aspergillus nidulans causes, under the attack of the fungivorous springtail folsomia candida, a disadvantage to the fungus. springtails exhibited a distinct preference for feeding on a mutant d ... | 2007 | 17686752 |
| rapid isolation of fungal genomic dna suitable for long distance pcr. | a quick and reliable method for screening fungal transformants for specific genetic modifications is essential for many molecular applications. we have compared the applicability of a few rapid dna extraction methods for myrothecium and aspergillus and tested the resulting dna as to its suitability for pcr. for myrothecium gramineum, the highest dna concentration was obtained with the procedure described by n. vanittanakom et al. (j clin microbiol 2002, 40: 1739-1742). for a. nidulans, concentra ... | 2007 | 17680211 |
| mating type and the genetic basis of self-fertility in the model fungus aspergillus nidulans. | sexual reproduction occurs in two fundamentally different ways: by outcrossing, in which two distinct partners contribute nuclei, or by self-fertilization (selfing), in which both nuclei are derived from the same individual. selfing is common in flowering plants, fungi, and some animal taxa. we investigated the genetic basis of selfing in the homothallic fungus aspergillus nidulans. we demonstrate that alpha and high-mobility group domain mating-type (mat) genes, found in outcrossing species, ar ... | 2007 | 17669651 |
| dioctatin a is a strong inhibitor of aflatoxin production by aspergillus parasiticus. | dioctatin a (dota), a metabolite of streptomyces, is known to be an inhibitor of human dipeptidyl aminopeptidase ii. here, it was found that dota strongly inhibited aflatoxin production by aspergillus parasiticus, with an ic50 value of 4.0 microm. the mycelial growth of the fungus was not affected by the addition of dota at a concentration of 50 microm, but inhibition of conidiation was observed at the same concentration. dota inhibited production of norsolorinic acid, an early biosynthetic inte ... | 2007 | 17660441 |
| asexual recombination in a uvsh mutant of aspergillus nidulans. | mutations in the gene uvsh of aspergillus nidulans result in increased spontaneous chromosome instability and increased intragenic and intergenic mitotic recombination in homozygous diploids. the aim of the present work was to obtain a uvs mutant of a. nidulans and to use it for the isolation of asexual recombinants (parameiotic segregants). the mutant uvsh, named b511, showed normal frequency of meiotic recombination in sexual crosses and high frequency of parameiotic segregants in the parasexu ... | 2007 | 17657356 |
| a single acyl-coa dehydrogenase is required for catabolism of isoleucine, valine and short-chain fatty acids in aspergillus nidulans. | an acyl-coa dehydrogenase has been identified as part of the mitochondrial beta-oxidation pathway in the ascomycete fungus aspergillus nidulans. disruption of the scda gene prevented use of butyric acid (c(4)) and hexanoic acid (c(6)) as carbon sources and reduced cellular butyryl-coa dehydrogenase activity by 7.5-fold. while the mutant strain exhibited wild-type levels of growth on erucic acid (c(22:1)) and oleic acid (c(18:1)), some reduction in growth was observed with myristic acid (c(14)). ... | 2008 | 17656140 |
| protein environment facilitates o2 binding in non-heme iron enzyme. an insight from oniom calculations on isopenicillin n synthase (ipns). | binding of dioxygen to a non-heme enzyme has been modeled using the oniom combined quantum mechanical/molecular mechanical (qm/mm) method. for the present system, isopenicillin n synthase (ipns), binding of dioxygen is stabilized by 8-10 kcal/mol for a qm:mm (b3lyp:amber) protein model compared to a quantum mechanical model of the active site only. in the protein system, the free energy change of o2 binding is close to zero. two major factors consistently stabilize o2 binding. the first effect, ... | 2007 | 17637052 |
| a small membrane-peripheral region close to the active center determines regioselectivity of membrane-bound fatty acid desaturases from aspergillus nidulans. | fatty acid desaturases catalyze the introduction of double bonds at specific positions of an acyl chain and are categorized according to their substrate specificity and regioselectivity. the current understanding of membrane-bound desaturases is based on mutant studies, biochemical topology analysis, and the comparison of related enzymes with divergent functionality. because structural information is lacking, the principles of membrane-bound desaturase specificity are still not understood despit ... | 2007 | 17636265 |
| the thioredoxin system of the filamentous fungus aspergillus nidulans: impact on development and oxidative stress response. | redox regulation has been shown to be of increasing importance for many cellular processes. here, redox homeostasis was addressed in aspergillus nidulans, an important model organism for fundamental biological questions such as development, gene regulation or the regulation of the production of secondary metabolites. we describe the characterization of a thioredoxin system from the filamentous fungus a. nidulans. the a. nidulans thioredoxin a (antrxa) is an 11.6-kda protein with a characteristic ... | 2007 | 17631497 |
| neurospora crassa ve-1 affects asexual conidiation. | the velvet factor of the homothallic fungus aspergillus nidulans promotes sexual fruiting body formation. the encoding vea gene is conserved among fungi, including the ascomycete neurospora crassa. there, the orthologous ve-1 gene encodes a deduced protein with high similarity to a. nidulans vea. cross-complementation experiments suggest that both the promoter and the coding sequence of n. crassa ve-1 are functional to complement the phenotype of an a. nidulans deletion mutant. moreover, ve-1 ex ... | 2008 | 17631397 |
| response regulators srra and sska are central components of a phosphorelay system involved in stress signal transduction and asexual sporulation in aspergillus nidulans. | among eukaryotes, only slime molds, fungi, and plants contain signal transduction phosphorelay systems. in filamentous fungi, multiple sensor kinases appear to use a single histidine-containing phosphotransfer (hpt) protein to relay signals to two response regulators (rr). in aspergillus nidulans, the rr sska mediates activation of the mitogen-activated protein kinase saka in response to osmotic and oxidative stress, whereas the functions of the rr srra were unknown. we used a genetic approach t ... | 2007 | 17630329 |
| aspergillus nidulans conidiation genes dewa, flug, and stua are differentially regulated in early vegetative growth. | microarray analysis was used to identify transcriptional changes in early vegetative growth of the filamentous fungus aspergillus nidulans. the results suggest that the previously identified conidiation genes dewa, flug, and stua may function in isotropic expansion during early vegetative growth and asexual reproduction. | 2007 | 17630328 |
| neuronal migration: unraveling the molecular pathway with humans, mice, and a fungus. | this review highlights the utility of comparative genetics in understanding the molecular mechanisms that underlie neuronal migration. it is apparent from studies in humans, mice, and a fungus that nuclear migration is a key component of neuronal migration and that both are dependent on a dynamic microtubule network. in vertebrates regulation of this network involves a complex pathway that is dependent on extracellular guidance cues, membrane-bound receptors, intracellular signaling molecules, p ... | 2007 | 17629745 |
| gene duplication, modularity and adaptation in the evolution of the aflatoxin gene cluster. | the biosynthesis of aflatoxin (af) involves over 20 enzymatic reactions in a complex polyketide pathway that converts acetate and malonate to the intermediates sterigmatocystin (st) and o-methylsterigmatocystin (omst), the respective penultimate and ultimate precursors of af. although these precursors are chemically and structurally very similar, their accumulation differs at the species level for aspergilli. notable examples are a. nidulans that synthesizes only st, a. flavus that makes predomi ... | 2007 | 17620135 |
| novel reporter gene expression systems for monitoring activation of the aspergillus nidulans hog pathway. | the aspergillus nidulans high-osmolarity glycerol response (anhog) pathway is involved in osmoadaptation. we found that fludioxonil, a fungicide, causes improper activation of hoga mitogen-activated protein kinase (mapk) in a. nidulans. here we present novel reporter systems for monitoring activation of the anhog pathway. the promoter region of gfdb (glycerol-3-phosphate dehydrogenase), whose expression depends on the presence of hoga, was fused to a beta-glucuronidase uida gene (gus) to constru ... | 2007 | 17617716 |
| characterization of the bzip-type transcription factor napa with reference to oxidative stress response in aspergillus nidulans. | microorganisms growing in natural habitats are constantly confronted with a wide variety of external stresses. here we provide several lines of experimental evidence for the thesis that the filamentous fungus aspergillus nidulans has a homolog of the ap-1-like bzip transcription factor, which is known to play general roles in oxidative responses in many types of yeast. | 2007 | 17617701 |
| histone deacetylase activity regulates chemical diversity in aspergillus. | bioactive small molecules are critical in aspergillus species during their development and interaction with other organisms. genes dedicated to their production are encoded in clusters that can be located throughout the genome. we show that deletion of hdaa, encoding an aspergillus nidulans histone deacetylase (hdac), causes transcriptional activation of two telomere-proximal gene clusters--and subsequent increased levels of the corresponding molecules (toxin and antibiotic)--but not of a telome ... | 2007 | 17616629 |
| fungal photoreceptors: sensory molecules for fungal development and behaviour. | light regulates fungal development and behaviour and activates metabolic pathways. in addition, light is one of the many signals that fungi use to perceive and interact with the environment. in the ascomycete neurospora crassa blue light is perceived by the white collar (wc) complex, a protein complex formed by wc-1 and wc-2. wc-1 is a protein with a flavin-binding domain and a zinc-finger domain, and interacts with wc-2, another zinc-finger domain protein. the wc complex operates as a photorece ... | 2007 | 17609765 |
| transformation of taxol-producing endophytic fungi by restriction enzyme-mediated integration (remi). | the remi method was used to introduce the plasmid pv2 harboring the hygromycin b phosphotransferase (hph) gene controlled by the aspergillus nidulans trpc promoter and the trpc terminator into a taxol-producing endophytic fungus bt2. remi transformation yielded stable transformants capable of continuing to grow on pda medium containing 125 mug ml(-1) hygromycin b. the transformation efficiency was about 5-6 transformants mug(-1) plasmid dna. the presence of hph gene in transformants was confirme ... | 2007 | 17608701 |
| mpka-dependent and -independent cell wall integrity signaling in aspergillus nidulans. | cell wall integrity signaling (cwis) maintains cell wall biogenesis in fungi, but only a few transcription factors (tfs) and target genes downstream of the cwis cascade in filamentous fungi are known. because a mitogen-activated protein kinase (mpka) is a key cwis enzyme, the transcriptional regulation of mpka and of cell wall-related genes (cwgs) is important in cell wall biogenesis. we cloned aspergillus nidulans mpka; rlma, a tf gene orthologous to saccharomyces cerevisiae rlm1 that encodes r ... | 2007 | 17601879 |
| a clc chloride channel plays an essential role in copper homeostasis in aspergillus nidulans at increased extracellular copper concentrations. | a putative clc voltage-gated anion channel gene from aspergillus nidulans (anclca) is characterised. the expression of the anclca cdna restored the iron-limited growth of the saccharomyces cerevisiae clc null mutant strain (gef1) suggesting that anclca functions as a chloride channel. an anclca conditional mutant was created and exhibited a strong and specific growth inhibition in the presence of extracellular copper concentrations >18 microm. this sensitivity was shown to be the result of a hyp ... | 2007 | 17601488 |
| analysis of septins across kingdoms reveals orthology and new motifs. | septins are cytoskeletal gtpase proteins first discovered in the fungus saccharomyces cerevisiae where they organize the septum and link nuclear division with cell division. more recently septins have been found in animals where they are important in processes ranging from actin and microtubule organization to embryonic patterning and where defects in septins have been implicated in human disease. previous studies suggested that many animal septins fell into independent evolutionary groups, conf ... | 2007 | 17601340 |
| nek7 is a centrosomal kinase critical for microtubule nucleation. | nima in aspergillus nidulans is a mitotic kinase for chromosome condensation and segregation. we characterized nek7, a human homologue of aspergillus nima. nek7 was located at the centrosome throughout the cell cycle. temporal localization of nek7 at midbody of the cytokinetic cell was also observed. nek7 knockdown by rnai caused a prometaphase arrest of the cell cycle with monopolar or disorganized spindle. we propose that such defects in spindle assembly are resulted from reduction in microtub ... | 2007 | 17586473 |
| a one-pot chemoenzymatic synthesis for the universal precursor of antidiabetes and antiviral bis-indolylquinones. | bis-indolylquinones represent a class of fungal natural products that display antiretroviral, antidiabetes, or cytotoxic bioactivities. recent advances in aspergillus genomic mining efforts have led to the discovery of the tdia-e-gene cluster, which is the first genetic locus dedicated to bis-indolylquinone biosynthesis. we have now genetically and biochemically characterized the enzymes tdia (bis-indolylquinone synthetase) and tdid (l-tryptophan:phenylpyruvate aminotransferase), which, together ... | 2007 | 17584611 |
| characterization of afpa, an alkaline foam protein from cultures of fusarium culmorum and its identification in infected malt. | the objective of this study was to evaluate the capability of fusarium culmorum to produce non-hydrophobin surface-active proteins in vitro, to isolate and characterize such proteins from liquid cultures, to analyse their effect on overfoaming (gushing) of beer and to elucidate their prevalence in pure cultures and infected malt. | 2007 | 17584451 |
| interaction of hapx with the ccaat-binding complex--a novel mechanism of gene regulation by iron. | iron homeostasis requires subtle control systems, as iron is both essential and toxic. in aspergillus nidulans, iron represses iron acquisition via the gata factor srea, and induces iron-dependent pathways at the transcriptional level, by a so far unknown mechanism. here, we demonstrate that iron-dependent pathways (e.g., heme biosynthesis) are repressed during iron-depleted conditions by physical interaction of hapx with the ccaat-binding core complex (cbc). proteome analysis identified putativ ... | 2007 | 17568774 |
| steric analysis of 8-hydroxy- and 10-hydroxyoctadecadienoic acids and dihydroxyoctadecadienoic acids formed from 8r-hydroperoxyoctadecadienoic acid by hydroperoxide isomerases. | 8-hydroxyoctadeca-9z,12z-dienoic acid (8-hode) and 10-hydroxyoctadeca-8e,12z-octadecadienoic acid (10-hode) are produced by fungi, e.g., 8r-hode by gaeumannomyces graminis (take-all of wheat) and aspergillus nidulans, 10s-hode by lentinula edodes, and 10r-hode by epichloe typhina. racemic [8-(2)h]8-hode and [10-(2)h]10-hode were prepared by oxidation of 8- and 10-hode to keto fatty acids by dess-martin periodinane followed by reduction to hydroxy fatty acids with nab(2)h(4). the hydroxy fatty ac ... | 2007 | 17553451 |
| molecular cloning, characterization, and expression of a chitinase from the entomopathogenic fungus paecilomyces javanicus. | paecilomyces javanicus is an entomopathogenic fungus of coleopteran and lepidopteran insects. here we report on cloning, characterization, and expression patterns of a chitinase from p. javanicus. a strong chitinase activity was detected in p. javanicus cultures added to chitin. the full-length cdna, designated pjchi-1, was cloned from mycelia by using both degenerate primer/reverse transcription polymerase chain reaction (rt-pcr) amplification and 5'-/3'-race extension. the 1.18-kb cdna gene co ... | 2007 | 17551789 |
| synthetic ecosystems based on airborne inter- and intrakingdom communication. | intercellular communication within an organism, between populations, or across species and kingdoms forms the basis of many ecosystems in which organisms coexist through symbiotic, parasitic, or predator-prey relationships. using multistep airborne communication and signal transduction, we present synthetic ecosystems within a mammalian cell population, in mice, or across species and kingdoms. inter- and intrakingdom communication was enabled by using sender cells that produce volatile aldehydes ... | 2007 | 17551014 |
| regulation of expression and kinetic modeling of substrate interactions of a uracil transporter in aspergillus nidulans. | early genetic evidence suggested that a. nidulans possesses at least one uracil transporter. a gene, named furd, was recently identified by reverse genetics and in silico approaches and we confirm here that it encodes a high-affinity, high-capacity, uracil transporter. in this work, we study the regulation of expression of furd and develop a kinetic model describing transporter-substrate interactions. the furd gene is not expressed in resting conidiospores, is transcriptionally activated and rea ... | 2007 | 17520477 |
| human nima-related kinase 6 is one of the fe65 ww domain binding proteins. | the aspergillus nidulans protein nima (never in mitosis, gene a) is a protein kinase required for initiation of mitosis, whereas its inactivation is necessary for mitotic exit. here, we present evidence that human nek6 is associated with fe65. based on the presence of fe65 ww domain binding motifs ((267)pplp(270)) in the nek6 catalytic domain, we observed that nek6 interacts physically with fe65 both in vivo and in vitro, using a pull-down approach. additionally, we detected co-localization of n ... | 2007 | 17512906 |
| the aspergillus nidulans putative kinase, kfsa (kinase for septation), plays a role in septation and is required for efficient asexual spore formation. | in aspergillus nidulans nuclear division and cytokinesis are coupled processes during asexual sporulation. metulae, phialides and conidia contain a single nucleus. here we describe the role of a putative saccharomyces cerevisiae kin4-related kinase, kfsa (kinase for septation) in the control of septum formation in a. nidulans. the kfsa deletion caused an increase in the number of conidiophores with septa in their stalks from 20% in wild type to 60% in the mutant strain. interestingly, 7% of metu ... | 2007 | 17500016 |
| the mitochondrial genome from the thermal dimorphic fungus paracoccidioides brasiliensis. | we present here the sequence of the mitochondrial dna of the pathogenic thermodimorphic fungus paracoccidioides brasiliensis, agent of an endemic disease in most south american countries. the sequenced genome has 71 334 bp and is organized as a circular molecule with two gaps of unknown size flanking the middle exon of the nad5 gene. we located genes coding for the three subunits of the atp synthase (atp6, atp8 and atp9), the apocytochrome b (cob), three subunits of the cytochrome c oxidase enzy ... | 2007 | 17492801 |
| 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 ... | 2006 | 17486980 |
| role of respiration in the germination process of the pathogenic mold aspergillus fumigatus. | inhalation of resting conidia is usually the first step of a systemic infection caused by the opportunistic fungal pathogen aspergillus fumigatus. in the lung, the inhaled spores encounter an environment that permits germination. however, the relative importance of certain environmental conditions for conidial activation and subsequent hyphae formation has so far not been analyzed in detail. in this study, we studied the role of oxygen during germination. we found that inhibitors of the respirat ... | 2007 | 17486408 |
| multiple fungal enzymes possess cysteine synthase activity in vitro. | we present evidence that there are at least three aspergillus nidulans enzymes which catalyze in vitro the reaction of o-acetylserine (oas) with sulfide forming cysteine. this activity is shared by cysteine synthase (cs) encoded by the cysb gene, homocysteine synthase encoded by cysd and by at least one more enzyme. moreover, arginine, histidine or proline starvation leads to derepression of cs activity even in the cysb,cysd double mutant strains, while neither cysb nor cysd gene transcription i ... | 2007 | 17482430 |
| an eight-subunit cop9 signalosome with an intact jamm motif is required for fungal fruit body formation. | fruit body formation in filamentous fungi is a complex and yet hardly understood process. we show here that protein turnover control is crucial for aspergillus nidulans development. deletion of genes encoding cop9 signalosome (csn) subunits 1, 2, 4, or 5 resulted in identical blocks in fruit body formation. the csn multiprotein complex controls ubiquitin-dependent protein degradation in eukaryotes. six csn subunits interacted in a yeast two-hybrid analysis, and the complete eight-subunit csn was ... | 2007 | 17470786 |
| coupling the gal4 uas system with alcr for versatile cell type-specific chemically inducible gene expression in arabidopsis. | the aspergillus alc regulon encodes a transcription factor, alcr, which regulates transcription from cognate promoters such as alca(p). in the presence of suitable chemical inducers, alcr activates gene expression from alca(p). the alc regulon can be transferred to other species and can be used to control the expression of reporter, metabolic and developmental genes in response to low-level ethanol exposure. in this paper, we describe a versatile system for targeting the alc regulon to specific ... | 2007 | 17470056 |
| mitotic recombination accelerates adaptation in the fungus aspergillus nidulans. | understanding the prevalence of sexual reproduction in eukaryotes is a hard problem. at least two aspects still defy a fully satisfactory explanation, the functional significance of genetic recombination and the great variation among taxa in the relative lengths of the haploid and diploid phases in the sexual cycle. we have performed an experimental study to explore the specific advantages of haploidy or diploidy in the fungus aspergillus nidulans. comparing the rate of adaptation to a novel env ... | 2007 | 17465683 |
| targeting polyamines of aspergillus nidulans by sirna specific to fungal ornithine decarboxylase gene. | aspergillus nidulans is a filamentous, ubiquitous and opportunistic pathogenic fungus, which causes fatal invasive aspergillosis among immunocompromised patients. as a prelude to the investigations on the possible control of human fungal diseases by selective targeting of fungal polyamines that are essential for fungal growth and development by rnai strategy, we have examined the effect of sirna specific to a key polyamine biosynthesis gene ornithine decarboxylase (odc) on the in vitro germinati ... | 2007 | 17464842 |
| 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 ... | 2006 | 17455791 |
| genetic manipulation of aspergillus nidulans: heterokaryons and diploids for dominance, complementation and haploidization analyses. | the haploid microbial eukaryote aspergillus nidulans is a powerful genetic system, which allows analysis of a broad range of biological phenomena. in addition to conventional analysis of meiotic progeny in a single generation, parasexual analysis affords a rapid and convenient method for genetic analysis. we describe the construction of a. nidulans heterokaryons and diploids for use in genetic analysis to determine dominance and conduct complementation tests. we also describe the rapid mapping o ... | 2007 | 17446882 |
| genetic manipulation of aspergillus nidulans: meiotic progeny for genetic analysis and strain construction. | the multicellular microbial eukaryote aspergillus nidulans is an excellent model for the study of a wide array of biological processes. studies in this system contribute significantly to understanding fundamental biological principles and are relevant for biotechnology and industrial applications, as well as human, animal and plant fungal pathogenesis. a. nidulans is easily manipulated using classical and molecular genetics. here, we describe the storage and handling of a. nidulans and procedure ... | 2007 | 17446881 |
| target-based approach to inhibitors of histone arginine methyltransferases. | lysine and arginine methyltransferases participate in the post-translational modification of histones and regulate key cellular functions. so far only one arginine methyltransferase inhibitor discovered by random screening was available. we present the first target-based approach to protein arginine methyltransferase (prmt) inhibitors. homology models of human and aspergillus nidulans prmt1 were generated from available x-ray structures of rat prmts. the nci diversity set was filtered by a targe ... | 2007 | 17432842 |
| purification and characterization of the feii- and alpha-ketoglutarate-dependent xanthine hydroxylase from aspergillus nidulans. | his6-tagged xanthine/alpha-ketoglutarate (alphakg) dioxygenase (xana) of aspergillus nidulans was purified from both the fungal mycelium and recombinant escherichia coli cells, and the properties of the two forms of the protein were compared. evidence was obtained for both n- and o-linked glycosylation on the fungus-derived xana, which aggregates into an apparent dodecamer, while bacterium-derived xana is free of glycosylation and behaves as a monomer. immunological methods identify phosphothreo ... | 2007 | 17429948 |
| 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 ... | 2006 | 17427290 |
| the sska and srra response regulators are implicated in oxidative stress responses of hyphae and asexual spores in the phosphorelay signaling network of aspergillus nidulans. | histidine-to-aspartate (his-asp) phosphorelay (or two-component) systems are common signal transduction mechanisms implicated in a wide variety of cellular responses to environmental stimuli in both prokaryotes and eukaryotes. for a model filamentous fungi, aspergillus nidulans, in this study we first compiled a complete list of his-asp phosphorelay components, including 15 genes for his-kinase (hk), four genes for response regulator (rr), and only one for histidine-containing phosphotransfer in ... | 2007 | 17420584 |
| further characterization of the signaling proteolysis step in the aspergillus nidulans ph signal transduction pathway. | the aspergillus nidulans ph-responsive transcription factor pacc is modulated by limited, two-step proteolysis. the first, ph-regulated cleavage occurs in the 24-residue highly conserved "signaling protease box" in response to the alkaline ph signal. this is transduced by the pal signaling pathway, containing the predicted calpain-like cysteine protease and likely signaling protease, palb. in this work, we carried out classical mutational analysis of the putative signaling protease palb, and we ... | 2007 | 17416893 |
| basa regulates cell wall organization and asexual/sexual sporulation ratio in aspergillus nidulans. | sphingolipid c4 hydroxylase catalyzes the conversion of dihydrosphingosine to phytosphingosine. in saccharomyces cerevisiae, sur2 is essential for sphingolipid c4 hydroxylation activity but not essential for normal growth. here we demonstrate that the aspergillus nidulans sur2 homolog basa is also required for phytosphingosine biosynthesis but is also essential for viability. we previously reported that a point missense mutation in basa resulted in aberrant cell wall thickening. here our data su ... | 2007 | 17409079 |
| the aspergillus nidulans pkca gene is involved in polarized growth, morphogenesis and maintenance of cell wall integrity. | the protein kinase c (pkc) family participates in maintaining integrity and growth of fungal cell walls. however, the precise molecular role of these proteins in the filamentous fungi remains unknown. in this work, pkca, the gene encoding the pkc homolog in the filamentous fungus aspergillus nidulans, was cloned and its function analyzed using a conditional alca-pkc mutant strain. repression of pkca expression resulted in increased conidial swelling, decreased rates of hyphal growth, changes in ... | 2007 | 17406869 |
| fusion pcr and gene targeting in aspergillus nidulans. | we describe a rapid method for the production of fusion pcr products that can be used, generally without band purification, to transform aspergillus nidulans. this technique can be used to replace genes; tag genes with fluorescent moeties or epitope tags; or replace endogenous promoters with regulatable promoters, by introducing an appropriate selective cassette (e.g., fluorescent protein + selectable marker). the relevant genomic fragments and cassette are first amplified separately by pcr usin ... | 2006 | 17406574 |
| identification and analysis of essential aspergillus nidulans genes using the heterokaryon rescue technique. | in the heterokaryon rescue technique, gene deletions are carried out using the pyrg nutritional marker to replace the coding region of target genes via homologous recombination in aspergillus nidulans. if an essential gene is deleted, the null allele is maintained in spontaneously generated heterokaryons that consist of two genetically distinct types of nuclei. one nuclear type has the essential gene deleted but has a functional pyrg allele (pyrg+). the other has the wild-type allele of the esse ... | 2006 | 17406500 |
| a homologue of the aspergillus velvet gene regulates both cephalosporin c biosynthesis and hyphal fragmentation in acremonium chrysogenum. | the aspergillus nidulans velvet (vea) gene encodes a global regulator of gene expression controlling sexual development as well as secondary metabolism. we have identified the vea homologue acvea from acremonium chrysogenum, the major producer of the beta-lactam antibiotic cephalosporin c. two different disruption strains as well as the corresponding complements were generated as a prelude to detailed functional analysis. northern hybridization and quantitative real-time pcr clearly indicate tha ... | 2007 | 17400783 |
| interactions of isopenicillin n synthase with cyclopropyl-containing substrate analogues reveal new mechanistic insight. | isopenicillin n synthase (ipns), a non-heme iron oxidase central to penicillin and cephalosporin biosynthesis, catalyzes an energetically demanding chemical transformation to produce isopenicillin n from the tripeptide delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine (acv). we describe the synthesis of two cyclopropyl-containing tripeptide analogues, delta-(l-alpha-aminoadipoyl)-l-cysteinyl-beta-methyl-d-cyclopropylglycine and delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-cyclopropylglycine, desig ... | 2007 | 17397141 |
| a regulator of a g protein signalling (rgs) gene, cag8, from the insect-pathogenic fungus metarhizium anisopliae is involved in conidiation, virulence and hydrophobin synthesis. | regulators of the g protein signalling (rgs) pathway have been implicated in the control of a diverse array of cellular functions, including conidiation in filamentous fungi. however, the regulatory processes involved in conidiation in insect-pathogenic fungi are poorly understood. since conidia are the infective propagules in these fungi, an understanding of the regulatory processes involved in conidiation is essential to the development of an effective biocontrol fungus. here, the cloning and ... | 2007 | 17379711 |
| the light-dependent regulator velvet a of aspergillus nidulans acts as a repressor of the penicillin biosynthesis. | the biosynthesis of the beta-lactam antibiotic penicillin in aspergillus nidulans is catalysed by three enzymes that are encoded by the genes acva, ipna and aata. several studies have indicated that these genes are controlled by a complex regulatory network, including a variety of cis-acting dna elements and regulatory factors. until now, however, relatively little information is available on external signals and their transmission influencing the expression of the structural genes. here, we sho ... | 2007 | 17375284 |
| genomics-driven discovery of pks-nrps hybrid metabolites from aspergillus nidulans. | in the postgenomic era it has become increasingly apparent that the vast number of predicted biosynthesis genes of microorganisms is not reflected by the metabolic profile observed under standard fermentation conditions. in the absence of a particular (in most cases unknown) trigger these gene loci remain silent. because these cryptic gene clusters may code for the biosynthesis of important virulence factors, toxins, or even drug candidates, new strategies for their activation are urgently neede ... | 2007 | 17369821 |
| the tightly regulated promoter of the xana gene of aspergillus nidulans is included in a helitron. | in aspergillus nidulans the xana gene codes for a xanthine alpha-ketoglutarate-dependent dioxygenase, an enzyme only present in the fungal kingdom. the 5' region of this gene, including its putative promoter and the first 54 codons of the open reading frame, together with the first intron is duplicated in the genome. this duplication corresponds to a helitron, a eukaryotic element proposed to transpose replicatively by the rolling circle mechanism. we show that the regulation of xana conforms to ... | 2007 | 17367381 |
| the proline permease of aspergillus nidulans: functional replacement of the native cysteine residues and properties of a cysteine-less transporter. | the major proline transporter (prnb) of aspergillus nidulans belongs to the amino acid polyamine organocation (apc) transporter superfamily. members of this family have not been subjected to systematic structure-function relationship studies. in this report, we examine the functional replacement of the three native cys residues (cys54, cys352 and cys530) of prnb and the properties of an engineered cys-less prnb protein, as background for employing a cys-scanning mutagenesis approach. we show tha ... | 2007 | 17350864 |
| genomics of aspergillus oryzae. | the genome sequence of aspergillus oryzae, a fungus used in the production of the traditional japanese fermentation foods sake (rice wine), shoyu (soy sauce), and miso (soybean paste), has revealed prominent features in its gene composition as compared to those of saccharomyces cerevisiae and neurospora crassa. the a. oryzae genome is extremely enriched with genes involved in biomass degradation, primary and secondary metabolism, transcriptional regulation, and cell signaling. even compared to t ... | 2007 | 17341818 |
| characterization of the nika histidine kinase implicated in the phosphorelay signal transduction of aspergillus nidulans, with special reference to fungicide responses. | we recently compiled a complete list of phosphorelay signal transduction components in the model filamentous fungus aspergillus nidulans. in this study, we characterized a histidine protein kinase (designated nika) that is found in many fungi, with special reference to responses to potent fungicides (iprodione and fludioxonil). we provided evidence that not only nika, but also two downstream response regulators (sska and srra) are crucially implicated in the mode of action of these fungicides, a ... | 2007 | 17341812 |
| transcriptional control of gluconeogenesis in aspergillus nidulans. | aspergillus nidulans can utilize carbon sources that result in the production of tca cycle intermediates, thereby requiring gluconeogenesis. we have cloned the acug gene encoding fructose-1,6 bisphosphatase and found that expression of this gene is regulated by carbon catabolite repression as well as by induction by a tca cycle intermediate similar to the induction of the previously studied acuf gene encoding phosphoenolpyruvate carboxykinase. the acun356 mutation results in loss of growth on gl ... | 2007 | 17339216 |
| the evolutionary history of cytochrome p450 genes in four filamentous ascomycetes. | the cytochrome p450 system is important in fungal evolution for adapting to novel ecological niches. to elucidate the evolutionary process of cytochrome p450 genes in fungi with different life styles, we studied the patterns of gene gains and losses in the genomes of four filamentous ascomycetes, including two saprotrophs (aspergillus nidulans (an) and neurospora crassa (nc)) and two plant pathogens (fusarium graminearum (fg) and magnaporthe grisea (mg)). | 2007 | 17324274 |
| small molecule inhibitors of histone arginine methyltransferases: homology modeling, molecular docking, binding mode analysis, and biological evaluations. | the screening of the inhibition capabilities of dye-like small molecules from a focused library against both human prmt1 and aspergillus nidulans rmta is reported as well as molecular modeling studies (homology modeling, molecular docking, and 3-d qsar) of the catalytic domain of the prmt1 fungal homologue rmta. the good correlation between computational and biological results makes rmta a reliable tool for screening arginine methyltransferase inhibitors. in addition, the binding mode analyses o ... | 2007 | 17323938 |
| genotoxicity (mitotic recombination) of the cancer chemotherapeutic agents cisplatin and cytosine arabinoside in aspergillus nidulans. | cisplatin (cis-diamminedichloroplatinum, cis-ddp) and cytosine arabinoside (ara-c) are anticancer drugs used in the treatment of human cancer. the two chemotherapeutic drugs were tested in current research for their recombinogenic potential in diploid cells of aspergillus nidulans. non-cytotoxic concentrations of ara-c (0.4 and 0.8 microm) and cis-ddp (1.5, 3.0 and 6.0 microm) were strong recombinagens in a. nidulans ut448//a757 diploid strain, which induced homozygosis of recessive genetic mark ... | 2007 | 17306432 |
| accurate prediction of the aspergillus nidulans terrequinone gene cluster boundaries using the transcriptional regulator laea. | laea is a regulatory protein of the genus aspergillus which controls global expression of secondary metabolism gene clusters. during a previous genome-wide transcriptional profiling screen, numerous novel gene clusters were found to be regulated by laea including a cluster required for the production of the antitumor agent terrequinone a. beginnings and ends of secondary metabolite gene clusters are difficult to predict by gene sequence alone, but sharp demarcation of transcriptional control by ... | 2007 | 17291795 |
| phosphopantetheinyl transferase cfwa/npga is required for aspergillus nidulans secondary metabolism and asexual development. | polyketide synthases (pkss) and/or nonribosomal peptide synthetases (nrpss) are central components of secondary metabolism in bacteria, plants, and fungi. in filamentous fungi, diverse pkss and nrpss participate in the biosynthesis of secondary metabolites such as pigments, antibiotics, siderophores, and mycotoxins. however, many secondary metabolites as well as the enzymes involved in their production are yet to be discovered. both pkss and nrpss require activation by enzyme members of the 4'-p ... | 2007 | 17277172 |
| oxylipins as developmental and host-fungal communication signals. | pathogenic microbes and their hosts have acquired complex signalling mechanisms to appraise themselves of the environmental milieu in the ongoing battle for survival. several recent studies have implicated oxylipins as a novel class of host-microbe signalling molecules. oxylipins represent a vast and diverse family of secondary metabolites that originate from the oxidation or further conversion of polyunsaturated fatty acids. among the microbial oxylipins, the fungal oxylipins are best character ... | 2007 | 17276068 |
| rapd typing of aspergillus chevalieri, aspergillus nidulans, aspergillus tetrazonus (quadrilineatus) and their teleomorphs using 5'-d[aacgcgcaac]-3' and 5'-d[cccgtcagca]-3' primers. | sexuality in fungi has long been a matter of concerns and debates that always necessitated extensive analysis of the relationship between organisms assumed to represent different developmental forms of the same organism. moreover, mating-virulence correlation and the growing worry of opportunistic fungal infections in immunocompromised states associated with aids, cancer chemotherapy and organ transplantation protocols have been critically addressed nowadays. in view of that, we genetically char ... | 2008 | 17268891 |
| l-arginine influences the structure and function of arginase mrna in aspergillus nidulans. | expression of the arginase structural gene (agaa) in aspergillus nidulans is subject to complex transcriptional and post-transcriptional regulation. arginase mrna has a long 5'-utr sequence. analysis of this sequence in silico revealed its putative complex secondary structure, the presence of arginine-binding motifs (arginine aptamers) and a short intron with two potential 3' splicing sites. in this report we present evidence that l-arginine (i) binds directly to the arginase 5'-utr; (ii) invoke ... | 2007 | 17261076 |
| synthesis, characterization and biological activity of complexes of 2-hydroxy-3,5-dimethylacetophenoneoxime (hdmaox) with copper(ii), cobalt(ii), nickel(ii) and palladium(ii). | a new series of complexes of 2-hydroxy-3,5-dimethyl acetophenone oxime (hdmaox) with cu(ii), co(ii), ni(ii) and pd(ii) have been prepared and characterized by different physical techniques. infrared spectra of the complexes indicate deprotonation and coordination of the phenolic oh. it also confirms that nitrogen atom of the oximino group contributes to the complexation. electronic spectra and magnetic susceptibility measurements reveal square planar geometry for cu(ii), ni(ii) and pd(ii) comple ... | 2007 | 17258502 |
| proteome map of aspergillus nidulans during osmoadaptation. | the model filamentous fungus aspergillus nidulans, when grown in a moderate level of osmolyte (+0.6m kcl), was previously found to have a significantly reduced cell wall elasticity (biotech prog, 21:292, 2005). in this study, comparative proteomic analysis via two-dimensional gel electrophoresis (2de) and matrix-assisted laser desorption ionization/time-of-flight (maldi-tof) mass spectrometry was used to assess molecular level events associated with this phenomenon. thirty of 90 differentially e ... | 2007 | 17258477 |
| two aspergillus nidulans genes encoding methylenetetrahydrofolate reductases are up-regulated by homocysteine. | methylenetetrahydrofolate reductase (mthfr) catalyzes the reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a co-substrate in the synthesis of methionine from homocysteine. we have cloned and characterized two aspergillus nidulans genes encoding mthfrs: meta and metf. mutations in either gene result in methionine requirement; the meta-encoded enzyme is responsible for only 10-15% of total mthfr activity. these two enzymes belong to different classes of mthfrs. mutations in ... | 2007 | 17257865 |
| development of novel real-time pcr assays for detection and differentiation of eleven medically important aspergillus and candida species in clinical specimens. | in the present study, novel real-time pcr assays targeting the fungal its2 region were developed for the detection and differentiation of medically important aspergillus species (aspergillus fumigatus, aspergillus flavus, aspergillus nidulans, aspergillus niger, and aspergillus terreus) and candida species (candida albicans, candida dubliniensis, candida glabrata, candida krusei, candida parapsilosis, and candida tropicalis) using a lightcycler instrument. the combination of a group-specific and ... | 2007 | 17251398 |
| induction of mitotic crossing-over in aspergillus nidulans by bifunctional alkylating agents. | 1963 | 17248183 | |
| induced somatic segregation in aspergillus nidulans. | 1960 | 17247964 | |
| mitochondrial four-point crosses in aspergillus nidulans : mapping of a suppressor of a mitochondrially inherited cold-sensitive mutation. | four-point mitochondrial crosses were conducted in heterokaryons of aspergillus nidulans. the mutations used were (olia1), conferring resistance to oligomycin, (cama112), conferring resistance to chloramphenicol; (cs-67), conferring cold-sensitivity, and ( sumd16), a suppressor of (cs-67). initially, the crosses were conducted by observing the segregation of extranuclear markers in heterokaryotic sectors emerging from the original point of heterokaryosis. this showed that (cama112), (cs-67) and ... | 1983 | 17246113 |
| a novel interaction between n-myristoylation and the 26s proteasome during cell morphogenesis. | n-myristoylation is a protein lipidation event in which myristate is covalently linked to the n-terminal glycine of target proteins. in aspergillus nidulans, the n-myristoylation deficient swof1 mutant was previously shown to lose cell polarity during the early morphogenic event of germ tube emergence. to further investigate this defect, we mutagenized swof1 and recovered six partial suppressors designated ssf (suppressor of swof1). the secondary mutations enabled swof1 to partially bypass its g ... | 2007 | 17238925 |
| point mutations in the stem region and the fourth aaa domain of cytoplasmic dynein heavy chain partially suppress the phenotype of nudf/lis1 loss in aspergillus nidulans. | cytoplasmic dynein performs multiple cellular tasks but its regulation remains unclear. the dynein heavy chain has a n-terminal stem that binds to other subunits and a c-terminal motor unit that contains six aaa (atpase associated with cellular activities) domains and a microtubule-binding site located between aaa4 and aaa5. in aspergillus nidulans, nudf (a lis1 homolog) functions in the dynein pathway, and two nudf6 partial suppressors were mapped to the nuda dynein heavy chain locus. here we i ... | 2007 | 17237507 |
| aspergillus nidulans dis1/xmap215 protein alpa localizes to spindle pole bodies and microtubule plus ends and contributes to growth directionality. | the dynamics of cytoplasmic microtubules (mts) is largely controlled by a protein complex at the mt plus end. in schizosaccharomyces pombe and in filamentous fungi, mt plus end-associated proteins also determine growth directionality. we have characterized the dis1/xmap215 family protein alpa from aspergillus nidulans and show that it determines mt dynamics as well as hyphal morphology. green fluorescent protein-tagged alpa localized to mt-organizing centers (centrosomes) and to mt plus ends. th ... | 2007 | 17237365 |
| differential expression of genes involved in iron metabolism in aspergillus fumigatus. | the ability of fungi to survive in many environments is linked to their capacity to acquire essential nutrients. iron is generally complexed and available in very limited amounts. like bacteria, fungi have evolved highly specific systems for iron acquisition. production and uptake of iron-chelating siderophores has been shown to be important for certain human bacterial pathogens, as well as in fungal pathogens such as cryptococcus neoformans and fusarium graminearum. this system also enables the ... | 2006 | 17236162 |
| characterization of regulatory non-catalytic hexokinases in aspergillus nidulans. | hexokinases catalyse the first step in glucose metabolism and play a role in glucose sensing in mammals, plants and fungi. we describe a new class of hexokinases that appear to be solely regulatory in function. the aspergillus nidulans hxkd gene (formerly named xprf) encodes a hexokinase-like protein. we constructed hxkddelta gene disruption mutants which showed increased levels of extracellular protease in response to carbon starvation. the hxkddelta mutations are not completely recessive, indi ... | 2007 | 17226029 |
| sulfate transport in aspergillus nidulans: a novel gene encoding alternative sulfate transporter. | in aspergillus nidulans sulfate is taken up by sulfate permease encoded by the sb gene. a unique tight auxotrophic mutant with an impaired promoter region of the sulfate permease gene, sb1(pr), was isolated. three suppressor genes were cloned by complementation of this mutation. one of them, described here, is the asta gene (alternative sulfate transporter) derived from a genomic library of the japanese a. nidulans iam 2006 strain. in the reference strain of glasgow origin the asta gene was foun ... | 2007 | 17223367 |
| highly efficient concerted evolution in the ribosomal dna repeats: total rdna repeat variation revealed by whole-genome shotgun sequence data. | repeat families within genomes are often maintained with similar sequences. traditionally, this has been explained by concerted evolution, where repeats in an array evolve "in concert" with the same sequence via continual turnover of repeats by recombination. another form of evolution, birth-and-death evolution, can also explain this pattern, although in this case selection is the critical force maintaining the repeats. the level of intragenomic variation is the key difference between these two ... | 2007 | 17200233 |
| application of molecular modeling to analysis of inhibition of kinesin motor proteins of the bimc subfamily by monastrol and related compounds. | application of molecular modeling approaches has potential to contribute to rational drug design. these approaches may be especially useful when attempting to elucidate the structural features associated with novel drug targets. in this study, molecular docking and molecular dynamics were applied to studies of inhibition of the human motor protein denoted hseg5 and other homologues in the bimc subfamily. these proteins are essential for mitosis, so compounds that inhibit their activity may have ... | 2005 | 17191952 |
| novel phacb-encoded cytochrome p450 monooxygenase from aspergillus nidulans with 3-hydroxyphenylacetate 6-hydroxylase and 3,4-dihydroxyphenylacetate 6-hydroxylase activities. | aspergillus nidulans catabolizes phenylacetate (phac) and 3-hydroxy-, 4-hydroxy-, and 3,4-dihydroxyphenylacetate (3-oh-phac, 4-oh-phac, and 3,4-dioh-phac, respectively) through the 2,5-dihydroxyphenylacetate (homogentisic acid) catabolic pathway. using cdna subtraction techniques, we isolated a gene, denoted phacb, which is strongly induced by phac (and its hydroxyderivatives) and encodes a new cytochrome p450 (cyp450). a disrupted phacb strain (delta phacb) does not grow on 3-hydroxy-, 4-hydrox ... | 2007 | 17189487 |
| susceptibility of environmental versus clinical strains of pathogenic aspergillus. | the objective of this study was to compare the antifungal susceptibility profiles of 307 environmental strains and 139 clinical isolates of aspergillus belonging to six different species. clinical and environmental strains with minimal inhibitory concentrations (mics) or minimal effective concentrations >or=4microg/ml to amphotericin b (amb), itraconazole (itc), voriconazole and caspofungin were seldom detected. however, the susceptibility profile of environmental aspergillus non-fumigatus strai ... | 2007 | 17189101 |
| the first filamentous fungal genome sequences: aspergillus leads the way for essential everyday resources or dusty museum specimens? | the published aspergillus genome sequences (a. nidulans, a. fumigatus, a. oryzae) and further sequence data from a. clavatus, neosartorya fischeri, a. flavus, a. niger, a. parasiticus and a. terreus are the first from a group of related filamentous fungi. they indicate the gains possible from genomic approaches, but also problems that arise after the sequences are finished. benefits include a greater understanding of genome structure and evolution, insights into gene regulation, predictions of n ... | 2007 | 17185529 |
| optimization of heterologous production of the polyketide 6-msa in saccharomyces cerevisiae. | polyketides are a group of natural products that have gained much interest due to their use as antibiotics, cholesterol lowering agents, immunosuppressors, and as other drugs. many organisms that naturally produce polyketides are difficult to cultivate and only produce these metabolites in small amounts. it is therefore of general interest to transfer polyketide synthase (pks) genes from their natural sources into heterologous hosts that can over-produce the corresponding polyketides. in this st ... | 2007 | 17171715 |
| an allosteric-feedback mechanism for protein-assisted group i intron splicing. | the i-anii maturase facilitates self-splicing of a mitochondrial group i intron in aspergillus nidulans. binding occurs in at least two steps: first, a specific but labile encounter complex rapidly forms and then this intermediate is slowly resolved into a native, catalytically active rna/protein complex. here we probe the structure of the rna throughout the assembly pathway. although inherently unstable, the intron core, when bound by i-anii, undergoes rapid folding to a near-native state in th ... | 2007 | 17164477 |
| aspergillus nidulans vea subcellular localization is dependent on the importin alpha carrier and on light. | the vea gene is a light-dependent regulator governing development and secondary metabolism in aspergillus nidulans. we have identified a putative bipartite nuclear localization signal (nls) motif in the a. nidulans vea amino acid sequence and demonstrated its functionality when expressed in yeast. furthermore, migration of vea to the nucleus was dependent on the importin alpha. this bipartite nls is also functional when vea is expressed in a. nidulans. interestingly, we found that vea migration ... | 2007 | 17163983 |
| identification of a novel gene, ure2, that functionally complements a urease-negative clinical strain of cryptococcus neoformans. | a urease-negative serotype a strain of cryptococcus neoformans (b-4587) was isolated from the cerebrospinal fluid of an immunocompetent patient with a central nervous system infection. the ure1 gene encoding urease failed to complement the mutant phenotype. urease-positive clones of b-4587 obtained by complementing with a genomic library of strain h99 harboured an episomal plasmid containing dna inserts with homology to the suda gene of aspergillus nidulans. the gene harboured by these plasmids ... | 2006 | 17159224 |
| effects of mutations in the ganb/rgsa g protein mediated signalling on the autolysis of aspergillus nidulans. | physiological changes taking place in carbon-starved, autolysing cultures of aspergillus (emericella) nidulans strains with mutations in the ganb/rgsa heterotrimeric g protein signalling pathway were studied and compared. deletion of the ganb, rgsa or both genes did not alter markedly either the autolytic loss of biomass or the extracellular chitinase production. however, they caused a significant decrease in the proteinase formation, which was detected by measuring both extracellular enzyme act ... | 2006 | 17139616 |
| differential physiological and developmental expression of the uapa and azga purine transporters in aspergillus nidulans. | in this article we study the cellular expression of uapa and azga, the two major purine transporters of aspergillus nidulans, by constructing strains expressing, from their native promoters, fully functional fluorescent (uapa-sgfp, azga-sgfp) or immunological (uapa-his) chimeric transporters. epifluorescence microscopy and immunodetection showed that under different physiological conditions and during aspergillus development: (i) uapa and azga expression in the plasma membrane becomes evident ea ... | 2007 | 17126042 |
| a chitinase gene, chib, involved in the autolytic process of aspergillus nidulans. | chitinases are thought to be involved in the morphogenesis and autolysis of filamentous fungi. we cloned a gene (chib) encoding a class v chitinase from aspergillus nidulans. chib expressed in escherichia coli had chitin-hydrolyzing activity, indicating that chib encoded a chitinase. deletion of chib affected neither germination efficiency nor hyphal growth rate, but considerably reduced the intracellular and extracellular chitinase activities. the decrease in hyphal dry weight during autolytic ... | 2007 | 17119968 |
| the protein kinase c orthologue pkca plays a role in cell wall integrity and polarized growth in aspergillus nidulans. | the calc2 mutation in aspergillus nidulans causes hypersensitivity to calcofluor white, along with other drug sensitivities that indicate a defect in cell wall integrity. we have cloned calc by complementation, isolating the a. nidulans orthologue of protein kinase c (pkca). the pkca allele of the calc2 strain contains a mutation predicted to introduce a charged arginine residue in place of neutral glycine at a conserved site located immediately beside the c1b regulatory domain. both pkca and ca ... | 2007 | 17118679 |
| nuclear export of the transcription factor nira is a regulatory checkpoint for nitrate induction in aspergillus nidulans. | nira, the specific transcription factor of the nitrate assimilation pathway of aspergillus nidulans, accumulates in the nucleus upon induction by nitrate. nira interacts with the nuclear export factor kapk, which bridges an interaction with a protein of the nucleoporin-like family (npla). nitrate induction disrupts the nira-kapk interaction in vivo, whereas kapk associates with nira when this protein is exported from the nucleus. a kpak leptomycin-sensitive mutation leads to inducer-independent ... | 2007 | 17116695 |
| metabolic network driven analysis of genome-wide transcription data from aspergillus nidulans. | aspergillus nidulans (the asexual form of emericella nidulans) is a model organism for aspergilli, which are an important group of filamentous fungi that encompasses human and plant pathogens as well as industrial cell factories. aspergilli have a highly diversified metabolism and, because of their medical, agricultural and biotechnological importance, it would be valuable to have an understanding of how their metabolism is regulated. we therefore conducted a genome-wide transcription analysis o ... | 2006 | 17107606 |
| a synchrotron ftir microspectroscopy investigation of fungal hyphae grown under optimal and stressed conditions. | synchrotron ftir can provide high spatial resolution (<10 microm pixel size) in situ biochemical analyses of intact biotissues, an area of increasing importance in the post-genomic era, as gene functions and gene networks are coming under direct scrutiny. with this technique, we can simultaneously assess multiple aspects of cell biochemistry and cytoplasmic composition. in this paper, we report the first results of our synchrotron ftir examination of hyphae of three important fungal model system ... | 2007 | 17106657 |
| fvve1 regulates filamentous growth, the ratio of microconidia to macroconidia and cell wall formation in fusarium verticillioides. | the velvet gene, vea, co-ordinates asexual and sexual development in the homothallic fungal species aspergillus nidulans. studies in aspergillus parasiticus and aspergillus fumigatus demonstrated that vea also regulates morphological differentiation in these species. whether vea has the same role in morphogenesis in other fungal genera has not been investigated. in this work, we studied the role of the vea homologue, fvve1, in the heterothallic fungus fusarium verticillioides. deletion of fvve1 ... | 2006 | 17054442 |