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development of transformation system of verticillium lecanii (lecanicillium spp.) (deuteromycotina: hyphomycetes) based on nitrate reductase gene of aspergillus nidulans.a heterologous transformation system was developed for v. lecanii based on the complementation of a nitrate reductase mutant. nitrate reductase mutants were obtained by resistance to chlorate in a rate of 23.24% when compared to other mutations that lead to the chlorate resistance. mutant no. 01 and 04 was chosen for the transformation experiments. plasmid pbt was used as transformation vector containing the aspergillus nidulans nitrate reductase gene. a frequency of approximately 3 transformant ...201122754022
otomycosis in central iran: a clinical and mycological study.otomycosis is a fungal infection of the external ear with bothersome symptoms. the aim of this study was to evaluate the prevalence of fungal agents, predisposing factors and characteristics of patients.201122737432
effects of laea deletion on aspergillus flavus conidial development and hydrophobicity may contribute to loss of aflatoxin production.laea of aspergillus nidulans is a putative methyltransferase and a component of the velvet complex; it is thought to mainly affect expression of genes required for the production of secondary metabolites. we found that although aspergillus flavus ca14 laea deletion mutants showed no aflatoxin production, expression of some of the early genes involved in aflatoxin formation, but not the later genes, could still be detected. the mutants grown in minimal medium supplemented with simple sugars and o ...201122289775
functional characterization and oligomerization of a recombinant xyloglucan-specific endo-β-1,4-glucanase (gh12) from aspergillus niveus.xyloglucan is a major structural polysaccharide of the primary (growing) cell wall of higher plants. it consists of a cellulosic backbone (beta-1,4-linked glucosyl residues) that is frequently substituted with side chains. this report describes aspergillus nidulans strain a773 recombinant secretion of a dimeric xyloglucan-specific endo-β-1,4-glucanohydrolase (xega) cloned from aspergillus niveus. the orf of the a. niveus xega gene is comprised of 714 nucleotides, and encodes a 238 amino acid pro ...201122230786
expression and characterization of an endo-1,4-β-galactanase from emericella nidulans in pichia pastoris for enzymatic design of potentially prebiotic oligosaccharides from potato galactans.potato pulp is a high-volume side-stream from industrial potato starch manufacturing. enzymatically solubilized β-1,4-galactan-rich potato pulp polysaccharides of molecular weights >100 kda (sppp) are highly bifidogenic in human fecal sample fermentations in vitro. the objective of the present study was to use potato β-1,4-galactan and the sppp as substrates for enzymatic production of potentially prebiotic compounds of lower and narrower molecular weight. a novel endo-1,4-β-galactanase from eme ...201122226198
currency notes and coins as a possible source of transmitting fungal pathogens of man and plants.currency (notes and coins) handling by people during transaction is one of the most mobile objects within the community, which has a potential of transmitting pathogens. a survey carried out recently in nanded city (maharashtra) revealed heavy contamination of currency notes and coins by important fungal pathogens of plants and man, i.e. aspergillus niger (60.37%), a. flavus (3.98%), a.nidulans (0.2%), penicillium citrinum (17.80%), alternaria tenuis (0.20%), curvularia pallescens (0.20%), clado ...201123505834
fungal secondary metabolites - strategies to activate silent gene clusters.filamentous fungi produce a multitude of low molecular weight bioactive compounds. the increasing number of fungal genome sequences impressively demonstrated that their biosynthetic potential is far from being exploited. in fungi, the genes required for the biosynthesis of a secondary metabolite are clustered. many of these bioinformatically newly discovered secondary metabolism gene clusters are silent under standard laboratory conditions. consequently, no product can be found. this review summ ...201120433937
the human ku autoantigen shares amino acid sequence homology with fungal, but not bacterial and viral, proteins.context: molecular mimicry between autoantigens and microbial antigens is a possible triggering mechanism of autoimmunity. human ku is a dna-associated autoantigen targeted by autoantibodies in patients with systemic lupus erythematosus and related disorders; available data are consistent with a role of molecular mimicry in the pathogenesis of anti-ku autoimmunity, but no research exist on this topic. objective: we aimed to define the most probable microbial triggers of anti-ku autoimmunity via ...201120718578
the gata-type transcriptional activator gat1 regulates nitrogen uptake and metabolism in the human pathogen cryptococcus neoformans.nitrogen uptake and metabolism are essential to microbial growth. gat1 belongs to a conserved family of zinc finger containing transcriptional regulators known as gata-factors. these factors activate the transcription of nitrogen catabolite repression (ncr) sensitive genes when preferred nitrogen sources are absent or limiting. cryptococcus neoformans gat1 is an ortholog to the aspergillus nidulans area and candida albicans gat1 genes. in an attempt to define the function of this transcriptional ...201120673806
characterization of the aspergillus nidulans biotin biosynthetic gene cluster and use of the bioda gene as a new transformation marker.the genes involved in the biosynthesis of biotin were identified in the hyphal fungus aspergillus nidulans through homology searches and complementation of escherichia coli biotin-auxotrophic mutants. whereas the 7,8-diaminopelargonic acid synthase and dethiobiotin synthetase are encoded by distinct genes in bacteria and the yeast saccharomyces cerevisiae, both activities are performed in a. nidulans by a single enzyme, encoded by the bifunctional gene bioda. such a bifunctional bioda gene is a ...201120713166
comparison of transcriptional and translational changes caused by long-term menadione exposure in aspergillus nidulans.under long-term oxidative stress caused by menadione sodium bisulfite, genome-wide transcriptional and proteome-wide translational changes were compared in aspergillus nidulans vegetative cells. the comparison of proteomic and dna microarray expression data demonstrated that global gene expression changes recorded with either flip-flop or dendrimer cdna labeling techniques supported proteome changes moderately with 40% and 34% coincidence coefficients, respectively. enzyme levels in the glycolyt ...201120797444
the paf gene product modulates asexual development in penicillium chrysogenum.penicillium chrysogenum secretes a low molecular weight, cationic and cysteine-rich protein (paf). it has growth inhibitory activity against the model organism aspergillus nidulans and numerous zoo- and phytopathogenic fungi but shows only minimal conditional antifungal activity against the producing organism itself. in this study we provide evidence for an additional function of paf which is distinct from the antifungal activity against putative ecologically concurrent microorganisms. our data ...201121298690
role of carnitine acetyltransferases in acetyl coenzyme a metabolism in aspergillus nidulans.the flow of carbon metabolites between cellular compartments is an essential feature of fungal metabolism. during growth on ethanol, acetate, or fatty acids, acetyl units must enter the mitochondrion for metabolism via the tricarboxylic acid cycle, and acetyl coenzyme a (acetyl-coa) in the cytoplasm is essential for the biosynthetic reactions and for protein acetylation. acetyl-coa is produced in the cytoplasm by acetyl-coa synthetase during growth on acetate and ethanol while ß-oxidation of fat ...201121296915
aspergillus nidulans transcription factor atfa interacts with the mapk saka to regulate general stress responses, development and spore functions.fungi utilize a phosphorelay system coupled to a map kinase module for sensing and processing environmental signals. in aspergillus nidulans, response regulator sska transmits osmotic and oxidative stress signals to the stress mapk (sapk) saka. using a genetic approach together with gfp tagging and molecular bifluorescence we show that saka and atf/creb transcription factor atfa define a general stress-signalling pathway that plays differential roles in oxidative stress responses during growth a ...201121320182
human nek6 is a monomeric mostly globular kinase with an unfolded short n-terminal domain.the nima-related kinases (neks) are widespread among eukaryotes. in mammalians they represent an evolutionarily conserved family of 11 serine/threonine kinases, with 40-45% amino acid sequence identity to the aspergillus nidulans mitotic regulator nima within their catalytic domains. neks have cell cycle-related functions and were recently described as related to pathologies, particularly cancer, consisting in potential chemotherapeutic targets. human nek6, -7 and -9 are involved in the control ...201121320329
characterization of aspergillus nidulans rabc/rab6.the aspergillus nidulans golgi is not stacked. early and late golgi equivalents (ges) are intermingled but can be resolved by epifluorescence microscopy. rabc, the aspergillus ortholog of mammalian rab6, is present across the golgi, preferentially associated with early ges near the tip and with late ges in tip-distal regions. rabc? mutants, showing markedly impaired apical extension, have conspicuously fragmented, brefeldin a-insensitive early and late ges, indicating that the golgi network orga ...201121226815
roles of the his-asp phosphorelay signal transduction system in controlling cell growth and development in aspergillus nidulans.the his-asp phosphorelay signal transduction system has been identified in most organisms, including bacteria, yeasts, fungi, and plants, except for animals. this system is important in adaptation to stress, control of cell growth, and induction of development in response to environmental changes. on the basis of genomic information, it has been found that aspergillus nidulans, a model species of fungi, includes 15 histidine kinases (hks), one histidine-containing phosphotransmitter protein (hpt ...201121228462
simultaneous detection and identification of aspergillus and mucorales species in tissues collected from patients with fungal rhinosinusitis.rapid detection and differentiation of aspergillus and mucorales species in fungal rhinosinusitis diagnosis are desirable, since the clinical management and prognosis associated with the two taxa are fundamentally different. we describe an assay based on a combination of broad-range pcr amplification and reverse line blot hybridization (pcr/rlb) to detect and differentiate the pathogens causing fungal rhinosinusitis, which include five aspergillus species (a. fumigatus, a. flavus, a. niger, a. t ...201121325541
characterization of the conserved phosphorylation site in the aspergillus nidulans response regulator srra.ssk1- and skn7-type response regulators are widely conserved in fungal his-asp phosphorelay (two-component) signaling systems. srra, a skn7-type rr of aspergillus nidulans, is implicated not only in oxidative stress responses but also in osmotic adaptation, conidia production (asexual development), inhibition by fungicides, and cell wall stress resistance. here, we characterized srra, focusing on the role of the conserved aspartate residue in the receiver domain, which is essential for phosphore ...201121229249
the cytoskeletal protein ndel1 regulates dynamin 2 gtpase activity.cytoskeleton dynamics, membranes trafficking and positioning are essential for the proper functioning of any mammalian cell. the identification of the molecules and mechanisms that allow these cellular processes to interface is vital for understanding cell behaviors. ndel1, the mammalian homolog of the aspergillus nidulans nude, organizes the cytoskeleton and regulates molecular motors, thereby impacting on the positioning of membranes. hypothetically, ndel1 can act in concert with enzymes contr ...201121283621
acon-3, the neurospora crassa ortholog of the developmental modifier, meda, complements the conidiation defect of the aspergillus nidulans mutant.aspergillus nidulans and neurospora crassa are ascomycetes that produce asexual spores through morphologically distinct processes. meda, a protein with unknown function, is required for normal asexual and sexual development in a. nidulans. we determined that the n. crassa ortholog of meda is acon-3, a gene required for early conidiophore development and female fertility. to test hypotheses about the evolutionary origins of asexual development in distinct fungal lineages it is important to unders ...201121220038
genome-based deletion analysis reveals the prenyl xanthone biosynthesis pathway in aspergillus nidulans.xanthones are a class of molecules that bind to a number of drug targets and possess a myriad of biological properties. an understanding of xanthone biosynthesis at the genetic level should facilitate engineering of second-generation molecules and increasing production of first-generation compounds. the filamentous fungus aspergillus nidulans has been found to produce two prenylated xanthones, shamixanthone and emericellin, and we report the discovery of two more, variecoxanthone a and epishamix ...201121351751
influence of substrate dideuteration on the reaction of the bifunctional heme enzyme psi factor producing oxygenase a (ppoa).ppoa is a bifunctional enzyme that catalyzes the dioxygenation of unsaturated c18 fatty acids. the products of this reaction are termed psi factors and have been shown to play a crucial role in conferring a balance between sexual and asexual spore development as well as production of secondary metabolites in the fungus aspergillus nidulans. studies on the reaction mechanism revealed that ppoa uses two different heme domains to catalyze two subsequent reactions. initially, the fatty acid substrat ...201121365732
functional characterization of rho gtpases in aspergillus niger uncovers conserved and diverged roles of rho proteins within filamentous fungi.rho gtpases are signalling molecules regulating morphology and multiple cellular functions including metabolism and vesicular trafficking. to understand the connection between polarized growth and secretion in the industrial model organism aspergillus niger, we investigated the function of all rho family members in this organism. we identified six rho gtpases in its genome and used loss-of-function studies to dissect their functions. while rhoa is crucial for polarity establishment and viability ...201121205013
restoration of anti-aspergillus defense by neutrophil extracellular traps in human chronic granulomatous disease after gene therapy is calprotectin-dependent.aspergillus spp infection is a potentially lethal disease in patients with neutropenia or impaired neutrophil function. we showed previously that aspergillus hyphae, too large for neutrophil phagocytosis, are inhibited by reactive oxygen species-dependent neutrophil extracellular trap (net) formation. this process is defective in chronic granulomatous disease (cgd) because of impaired phagocyte nicotinamide adenine dinucleotide phosphate (nadph) oxidase function.201121376380
fluorinated substrates result in variable leakage of a reaction intermediate during catalysis by dehydroquinate synthase.incubation of (3s)-3-fluoro-3-deoxy-d-arabino-heptulosonate 7-phosphate with dehydroquinate (dhq) synthase from three phylogenetically distinct sources resulted in the production of (6s)-6-fluorodhq and its epimer 1-epi-(6s)-6-fluorodhq. the differences in the product ratios of the reactions catalysed by each enzyme imply that 1-epi-(6s)-6-fluorodhq formation occurs by an unusual partial leakage of a reaction intermediate from the enzyme.201121387027
the aspergillus nidulans cenp-e kinesin motor kipa interacts with the fungal homologue of the centromere-associated protein cenp-h at the kinetochore.chromosome segregation is an essential process for nuclear and cell division. the microtubule cytoskeleton, molecular motors and protein complexes at the microtubule plus ends and at kinetochores play crucial roles in the segregation process. here we identified kata (kipatarget protein, homologue of cenp-h) as a kinesin-7 (kipa, homologue of human cenp-e) interacting protein in aspergillus nidulans. kata located at the kinetochore during the whole cell cycle and colocalized with kipa and partial ...201121392133
agrobacterium tumefasciens-mediated transformation of the aquatic fungus blastocladiella emersonii.agrobacterium tumefaciens is widely used for plant dna transformation and more recently, has also been used to transform yeast, filamentous fungi and even human cells. using this technique, we developed the first transformation protocol for the saprobic aquatic fungus blastocladiella emersonii, a blastocladiomycete localized at the base of fungal phylogenetic tree, which has been shown as a promising and interesting model of study of cellular function and differentiation. we constructed binary t ...201121396477
versatile enzyme expression and characterization system for aspergillus nidulans, with the penicillium brevicompactum polyketide synthase gene from the mycophenolic acid gene cluster as a test case.assigning functions to newly discovered genes constitutes one of the major challenges en route to fully exploiting the data becoming available from the genome sequencing initiatives. heterologous expression in an appropriate host is central in functional genomics studies. in this context, filamentous fungi offer many advantages over bacterial and yeast systems. to facilitate the use of filamentous fungi in functional genomics, we present a versatile cloning system that allows a gene of interest ...201121398493
how protein kinases co-ordinate mitosis in animal cells.mitosis is associated with profound changes in cell physiology and a spectacular surge in protein phosphorylation. to accomplish these, a remarkably large portion of the kinome is involved in the process. in the present review, we will focus on classic mitotic kinases, such as cyclin-dependent kinases, polo-like kinases and aurora kinases, as well as more recently characterized players such as nima (never in mitosis in aspergillus nidulans)-related kinases, greatwall and haspin. together, these ...201121406064
completing the purine utilisation pathway of aspergillus nidulans.we have previously identified by classical genetics and biochemistry, all the genes of aspergillus nidulans predicted to be involved in purine utilisation, together with cognate regulatory genes and one gene encoding a novel xanthine hydroxylation activity. in this article we complete the description of the purine utilisation pathway with the identification of the two genes (uax and uaw) encoding the enzymes catalysing the conversion of the product of urate oxidation by urate oxidase, 5-hydroxyi ...201121419234
wild-type mic distributions and epidemiological cutoff values for caspofungin and aspergillus spp. for the clsi broth microdilution method (m38-a2 document).clinical breakpoints have not been established for mold testing. epidemiologic cutoff values (ecvs) are available for six aspergillus spp. and the triazoles, but not for caspofungin. wild-type (wt) minimal effective concentration (mec) distributions (organisms in a species-drug combination with no acquired resistance mechanisms) were defined in order to establish ecvs for six aspergillus spp. and caspofungin. the number of available isolates was as follows: 1,691 a. fumigatus, 432 a. flavus, 192 ...201121422219
elucidation of functional markers from aspergillus nidulans developmental regulator flbb and their phylogenetic distribution.aspergillus nidulans is a filamentous fungus widely used as a model for biotechnological and clinical research. it is also used as a platform for the study of basic eukaryotic developmental processes. previous studies identified and partially characterized a set of proteins controlling cellular transformations in this ascomycete. among these proteins, the bzip type transcription factor flbb is a key regulator of reproduction, stress responses and cell-death. our aim here was the prediction, thro ...201121423749
peritonitis due to aspergillus nidulans and its effective treatment with voriconazole: the first case report. 201121427255
recruitment of class i hydrophobins to the air:water interface initiates a multi-step process of functional amyloid formation.class i fungal hydrophobins form amphipathic monolayers composed of amyloid rodlets. this is a remarkable case of functional amyloid formation in that a hydrophobic:hydrophilic interface is required to trigger the self-assembly of the proteins. the mechanism of rodlet formation and the role of the interface in this process have not been well understood. here, we have studied the effect of a range of additives, including ionic liquids, alcohols, and detergents, on rodlet formation by two class i ...201121454575
glutathione reductase/glutathione is responsible for cytotoxic elemental sulfur tolerance via polysulfide shuttle in fungi.fungi that can reduce elemental sulfur to sulfide are widely distributed, but the mechanism and physiological significance of the reaction have been poorly characterized. here, we purified elemental sulfur-reductase (sr) and cloned its gene from the elemental sulfur-reducing fungus fusarium oxysporum. we found that nadph-glutathione reductase (gr) reduces elemental sulfur via glutathione as an intermediate. a loss-of-function mutant of the sr/gr gene generated less sulfide from elemental sulfur ...201121474441
purification and characterization of antifungal δ-dodecalactone from lactobacillus plantarum af1 isolated from kimchi.the aim of this study was to purify and identify an antifungal compound from lactobacillus plantarum af1, which was isolated from kimchi. the antifungal compound was purified by solid-phase extraction and recycling preparative high-performance liquid chromatography, and its structure was elucidated by using gas chromatography-mass spectrometry (gc-ms). the active compound from l. plantarum af1 was confirmed to be δ-dodecalactone (molecular weight, 198.3) by comparison of its gas chromatographic ...201121477483
structural features and chaperone activity of the nudc protein family.the nudc family consists of four conserved proteins with representatives in all eukaryotes. the archetypal nudc gene from aspergillus nidulans is a member of the nud gene family that is involved in the maintenance of nuclear migration. this family also includes nudf, whose human orthologue, lis1, codes for a protein essential for brain cortex development. three paralogues of nudc are known in vertebrates: nudc, nudc-like (nudcl), and nudc-like 2 (nudcl2). the fourth distantly related member of t ...201121530541
8-carbon oxylipins inhibit germination and growth, and stimulate aerial conidiation in aspergillus nidulans.germination of aspergillus nidulans conidia in liquid cultures was progressively inhibited at inoculum loads above 1×10(5)conidiaml(-1). high conidial densities also inhibited growth of neighbouring mycelia. the eight-carbon oxylipin 1-octen-3-ol was identified as the main inhibitor in a fraction also containing 3-octanone and 3-octanol. these three oxylipins also increased the conidiation rate of dark-grown surface cultures, but had no effect on liquid cultures. 3-octanone was the most conidiog ...201121530921
multifrequency electron paramagnetic resonance characterization of ppoa, a cyp450 fusion protein that catalyzes fatty acid dioxygenation.ppoa is a fungal dioxygenase that produces hydroxylated fatty acids involved in the regulation of the life cycle and secondary metabolism of aspergillus nidulans . it was recently proposed that this novel enzyme employs two different heme domains to catalyze two separate reactions: within a heme peroxidase domain, linoleic acid is oxidized to (8r)-hydroperoxyoctadecadienoic acid [(8r)-hpode]; in the second reaction step (8r)-hpode is isomerized within a p450 heme thiolate domain to 5,8-dihydroxy ...201121548577
transcription of the hsp30, hsp70, and hsp90 heat shock protein genes is modulated by the pala protein in response to acid ph-sensing in the fungus aspergillus nidulans.heat shock proteins are molecular chaperones linked to a myriad of physiological functions in both prokaryotes and eukaryotes. in this study, we show that the aspergillus nidulans hsp30 (anid_03555.1), hsp70 (anid_05129.1), and hsp90 (anid_08269.1) genes are preferentially expressed in an acidic milieu, whose expression is dependent on the pala (+) background under optimal temperature for fungal growth. heat shock induction of these three hsp genes showed different patterns in response to extrac ...201121553327
quantitative trait locus (qtl) mapping reveals a role for unstudied genes in aspergillus virulence.infections caused by the fungus aspergillus are a major cause of morbidity and mortality in immunocompromised populations. to identify genes required for virulence that could be used as targets for novel treatments, we mapped quantitative trait loci (qtl) affecting virulence in the progeny of a cross between two strains of a. nidulans (fgsc strains a4 and a91). we genotyped 61 progeny at 739 single nucleotide polymorphisms (snp) spread throughout the genome, and constructed a linkage map that wa ...201121559404
nmr structure of the c-terminal domain of a tyrosyl-trna synthetase that functions in group i intron splicing.the mitochondrial tyrosyl-trna synthetases (mt tyrrss) of pezizomycotina fungi are bifunctional proteins that aminoacylate mitochondrial trna(tyr) and are structure-stabilizing splicing cofactors for group i introns. studies with the neurospora crassa synthetase (cyt-18 protein) showed that splicing activity is dependent upon pezizomycotina-specific structural adaptations that form a distinct group i intron-binding site in the n-terminal catalytic domain. although cyt-18's c-terminal domain also ...201121438536
asperlin induces g(2)/m arrest through ros generation and atm pathway in human cervical carcinoma cells.we exploited the biological activity of an antibiotic agent asperlin isolated from aspergillus nidulans against human cervical carcinoma cells. we found that asperlin dramatically increased reactive oxygen species (ros) generation accompanied by a significant reduction in cell proliferation. cleavage of caspase-3 and parp and reduction of bcl-2 could also be detected after asperlin treatment to the cells. an anti-oxidant n-acetyl-l-cysteine (nac), however, blocked all the apoptotic effects of as ...201121600879
cryptic aspergillus nidulans antimicrobials.secondary metabolite (sm) production by fungi is hypothesized to provide some fitness attribute for the producing organisms. however, most sm clusters are "silent" when fungi are grown in traditional laboratory settings, and it is difficult to ascertain any function or activity of these sm cluster products. recently, the creation of a chromatin remodeling mutant in aspergillus nidulans induced activation of several cryptic sm gene clusters. systematic testing of nine purified metabolites from th ...201121478304
regulation of pentose utilisation by arar, but not xlnr, differs in aspergillus nidulans and aspergillus niger.filamentous fungi are important producers of plant polysaccharide degrading enzymes that are used in many industrial applications. these enzymes are produced by the fungus to liberate monomeric sugars that are used as carbon source. two of the main components of plant polysaccharides are l: -arabinose and d: -xylose, which are metabolized through the pentose catabolic pathway (pcp) in these fungi. in aspergillus niger, the regulation of pentose release from polysaccharides and the pcp involves t ...201121484208
eisosomes and membrane compartments in the ascomycetes: a view from aspergillus nidulans.eisosomes are punctate structures located in the cytoplasmic side of the cell membrane of ascomycetes. in saccharomyces cerevisiae they coincide topologically with and are necessary for the organisation of specific membrane domains. the eisosomal proteins are universally and quite strictly conserved in the sub-phylum, however this evolutionary conservation is in apparent contradiction with an elusive functional significance. the comparative analysis of the eisosomes of s. cerevisiae and aspergil ...201121509182
enzymatic properties of the recombinant serine-type carboxypeptidase ocpc, which is unique to aspergillus oryzae.gene ao090103000153 is unique to aspergillus oryzae rib40 and a. flavus nrrl3357, and is speculated to encode a serine-type carboxypeptidase. in this study, we purified and characterized a heterologously expressed gene product of ao090103000153. 5'-rapid amplification of cdna ends indicated that the translation start site of the gene is located 1,586 bp downstream of the translation start site predicted by the genome sequencing project. the gene, starting from the revised translation start codon ...201121512241
ph response pathways in fungi: adapting to host-derived and environmental signals.microorganisms are significantly affected when the ambient ph of their environment changes. they must therefore be able to sense and respond to these changes in order to survive. previous investigators have studied various fungal species to define conserved ph-responsive signaling pathways. one of these pathways, known as the pal/rim pathway, is activated in response to alkaline ph signals, ultimately targeting the pacc/rim101 transcription factor. although the central signaling components are c ...201122783112
the echinocandin b producer fungus aspergillus nidulans var. roseus atcc 58397 does not possess innate resistance against its lipopeptide antimycotic.aspergillus nidulans var. roseus atcc 58397 is an echinocandin b (ecb) producer ascomycete with great industrial importance. as demonstrated by ecb/caspofungin sensitivity assays, a. nidulans var. roseus does not possess any inherent resistance to echinocandins, and its tolerance to these lipopeptide antimycotics are even lower than those of the non-producer a. nidulans fgsc a4 strain. under ecb producing conditions or ecb exposures, a. nidulans var. roseus induced its ecb tolerance via up-regul ...201222555909
ambient ph controls glycogen levels by regulating glycogen synthase gene expression in neurospora crassa. new insights into the ph signaling pathway.glycogen is a polysaccharide widely distributed in microorganisms and animal cells and its metabolism is under intricate regulation. its accumulation in a specific situation results from the balance between glycogen synthase and glycogen phosphorylase activities that control synthesis and degradation, respectively. these enzymes are highly regulated at transcriptional and post-translational levels. the existence of a dna motif for the aspergillus nidulans ph responsive transcription factor pacc ...201222952943
γ-tubulin plays a key role in inactivating apc/c(cdh1) at the g(1)-s boundary.a γ-tubulin mutation in aspergillus nidulans, mipa-d159, causes failure of inactivation of the anaphase-promoting complex/cyclosome (apc/c) in interphase, resulting in failure of cyclin b (cb) accumulation and removal of nuclei from the cell cycle. we have investigated the role of cdha, the a. nidulans homologue of the apc/c activator protein cdh1, in γ-tubulin-dependent inactivation of the apc/c. cdha was not essential, but it targeted cb for destruction in g(1), and apc/c(cdha) had to be inact ...201222927465
morphogenetic and developmental functions of the aspergillus nidulans homologues of the yeast bud site selection proteins bud4 and axl2.the yeast bud site selection system represents a paradigm for understanding how fungal cells regulate the formation of a polarity axis. in saccharomyces cerevisiae, bud4 and axl2 are components of the axial bud site marker. to address the possibility that these proteins regulate cellular morphogenesis in filamentous fungi, we have characterized homologues of bud4 and axl2 in aspergillus nidulans. our results show that bud4 is involved in septum formation in both hyphae and developing conidiophor ...201222651396
searching for gold beyond mitosis: mining intracellular membrane traffic in aspergillus nidulans.the genetically tractable filamentous ascomycete fungus aspergillus nidulans has been successfully exploited to gain major insight into the eukaryotic cell cycle. more recently, its amenability to in vivo multidimensional microscopy has fueled a potentially gilded second age of a. nidulans cell biology studies. this review specifically deals with studies on intracellular membrane traffic in a. nidulans. the cellular logistics are subordinated to the needs imposed by the polarized mode of growth ...201222645705
motor-driven motility of fungal nuclear pores organizes chromosomes and fosters nucleocytoplasmic transport.exchange between the nucleus and the cytoplasm is controlled by nuclear pore complexes (npcs). in animals, npcs are anchored by the nuclear lamina, which ensures their even distribution and proper organization of chromosomes. fungi do not possess a lamina and how they arrange their chromosomes and npcs is unknown. here, we show that motor-driven motility of npcs organizes the fungal nucleus. in ustilago maydis, aspergillus nidulans, and saccharomyces cerevisiae fluorescently labeled npcs showed ...201222851316
identification of the substrate recognition and transport pathway in a eukaryotic member of the nucleobase-ascorbate transporter (nat) family.using the crystal structure of the uracil transporter uraa of escherichia coli, we constructed a 3d model of the aspergillus nidulans uric acid-xanthine/h(+) symporter uapa, which is a prototype member of the nucleobase-ascorbate transporter (nat) family. the model consists of 14 transmembrane segments (tmss) divided into a core and a gate domain, the later being distinctly different from that of uraa. by implementing molecular mechanics (mm) simulations and quantitative structure-activity relat ...201222848666
identification and molecular genetic analysis of the cichorine gene cluster in aspergillus nidulans.we recently demonstrated that the phytotoxin cichorine is produced by aspergillus nidulans. through a set of targeted deletions, we have found a cluster of seven genes that are required for its biosynthesis. two of the deletions yielded molecules that give information about the biosynthesis of this metabolite.201224244835
proteome analysis of the farnesol-induced stress response in aspergillus nidulans--the role of a putative dehydrin.the isoprenoid alcohol farnesol represents a quorum-sensing molecule in pathogenic yeasts, but was also shown to inhibit the growth of many filamentous fungi. in order to gain a deeper insight into the antifungal activity of farnesol, we performed 2d-differential gel electrophoretic analysis (2d-dige) of aspergillus nidulans exposed to farnesol. we observed an increased abundance of antioxidative enzymes and proteins involved in protein folding and the ubiquitin-mediated protein degradation. a s ...201222634043
cryptic peroxisomal targeting via alternative splicing and stop codon read-through in fungi.peroxisomes are eukaryotic organelles important for the metabolism of long-chain fatty acids. here we show that in numerous fungal species, several core enzymes of glycolysis, including glyceraldehyde-3-phosphate dehydrogenase (gapdh) and 3-phosphoglycerate kinase (pgk), reside in both the cytoplasm and peroxisomes. we detected in these enzymes cryptic type 1 peroxisomal targeting signals (pts1), which are activated by post-transcriptional processes. notably, the molecular mechanisms that genera ...201222622582
an efficient method for transient gene expression in monocots applied to modify the brachypodium distachyon cell wall.agrobacterium-mediated transformation is widely used to produce insertions into plant genomes. there are a number of well-developed agrobacterium-mediated transformation methods for dicotyledonous plants, but there are few for monocotyledonous plants.201222589326
fungal s-adenosylmethionine synthetase and the control of development and secondary metabolism in aspergillus nidulans.the filamentous fungus aspergillus nidulans carries a single gene for the s-adenosylmethionine (sam) synthetase sasa, whereas many other organisms possess multiple sam synthetases. the conserved enzyme catalyzes the reaction of methionine and atp to the ubiquitous methyl group donor sam. sam is the main methyl group donor for methyltransferases to modify dna, rna, protein, metabolites, or phospholipid target substrates. we show here that the single a. nidulans sam synthetase encoding gene sasa i ...201222561085
induced mitotic homologous recombination by the babesicide imidocarb dipropionate in aspergillus nidulans diploid cells.imidocarb dipropionate (imd) is a chemotherapeutic agent prescribed for the treatment and control of babesiosis; it is known to be a nucleic acid synthesis inhibitor. although it is an effective babesicide, there are reports of persistent imd residues retained at high levels in edible tissues of cattle, swine and sheep, raising concerns about potential effects on humans. since the carcinogenic potential of a chemical compound can be assessed through its effect on the homologous recombination, we ...201222869537
cis- and trans-acting localization determinants of ph response regulator rim13 in saccharomyces cerevisiae.the rim101/pacc pathway governs adaptation to alkaline ph in many fungi. output of the pathway is mediated by transcription factors of the rim101/pacc family, which are activated by proteolytic cleavage. the proteolytic complex includes scaffold protein rim20 and endosome-associated subunits of the endosomal sorting complex required for transport (escrt). we provide here evidence that saccharomyces cerevisiae rim13, the protease that is implicated in rim101 cleavage, is associated with the rim20 ...201222865500
involvement of a natural fusion of a cytochrome p450 and a hydrolase in mycophenolic acid biosynthesis.mycophenolic acid (mpa) is a fungal secondary metabolite and the active component in several immunosuppressive pharmaceuticals. the gene cluster coding for the mpa biosynthetic pathway has recently been discovered in penicillium brevicompactum, demonstrating that the first step is catalyzed by mpac, a polyketide synthase producing 5-methylorsellinic acid (5-moa). however, the biochemical role of the enzymes encoded by the remaining genes in the mpa gene cluster is still unknown. based on bioinfo ...201222544261
mrna 3' tagging is induced by nonsense-mediated decay and promotes ribosome dissociation.for a range of eukaryote transcripts, the initiation of degradation is coincident with the addition of a short pyrimidine tag at the 3' end. previously, cytoplasmic mrna tagging has been observed for human and fungal transcripts. we now report that arabidopsis thaliana mrna is subject to 3' tagging with u and c nucleotides, as in aspergillus nidulans. mutations that disrupt tagging, including a. nidulans cuta and a newly characterized gene, cutb, retard transcript degradation. importantly, nonse ...201222547684
effects of sterigmatocystin on tnf-α, il-6 and il-12 expression in murine peripheral blood mononuclear cells and peritoneal macrophages in vivo.sterigmatocystin (st) is a toxic metabolite mainly produced by the fungi aspergillus nidulans and aspergillus versicolor. st is considered a potent carcinogen, mutagen and teratogen. however, over the past few years, it has been demonstrated that it is less acutely toxic to rodents in vivo. in this study, we evaluated the putative effects of st on the expression of tumor necrosis factor-α (tnf-α), interleukin (il)-6 and il-12 at mrna levels in murine peripheral blood mononuclear cells (mpbmcs) a ...201222344519
γ-heptalactone is an endogenously produced quorum-sensing molecule regulating growth and secondary metabolite production by aspergillus nidulans.microbes monitor their population density through a mechanism termed quorum sensing. it is believed that quorum-sensing molecules diffuse from the microbial cells and circulate in the surrounding environment as a function of cell density. when these molecules reach a threshold concentration, the gene expression of the entire population is altered in a coordinated manner. this work provides evidence that aspergillus nidulans produces at least one small diffusible molecule during its growth cycle ...201222543352
α-glucosylated 6-gingerol: chemoenzymatic synthesis using α-glucosidase from halomonas sp. h11, and its physical properties.6-gingerol [(s)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)decan-3-one] is a biologically active compound and is abundant in the rhizomes of ginger (zingiber officinale). it has some beneficial functions in healthcare, but its use is limited because of its insolubility in water and its heat-instability. to improve these physical properties, the glucosylation of 6-gingerol was investigated using α-glucosidases (ec. 3.2.1.20) from aspergillus niger, aspergillus nidulans abpu1, acremonium strictum, hal ...201222537860
lae1 regulates expression of multiple secondary metabolite gene clusters in fusarium verticillioides.the filamentous fungus fusarium verticillioides can cause disease of maize and is capable of producing fumonisins, a family of toxic secondary metabolites linked to esophageal cancer and neural tube defects in humans and lung edema in swine and leukoencephalomalacia in equines. the expression of fumonisin biosynthetic genes is influenced by broad-domain transcription factors (global regulators) and fum21, a pathway-specific transcription factor. laea is a global regulator that in aspergillus nid ...201222713715
fgvelb is associated with vegetative differentiation, secondary metabolism and virulence in fusarium graminearum.the velvet complex containing vea, velb and laea has been showed to play critical roles in the regulation of secondary metabolism and diverse cellular processes in aspergillus spp. in this study, we identified fgvelb, a homolog of aspergillus nidulans velb, from fusarium graminearum using the blastp program. disruption of fgvelb gene led to several phenotypic defects, including suppression of aerial hyphae formation, reduced hyphal hydrophobicity and highly increased conidiation. the mutant show ...201222713714
lis1 is an initiation factor for dynein-driven organelle transport.the molecular motor cytoplasmic dynein is responsible for most minus-end-directed, microtubule-based transport in eukaryotic cells. it is especially important in neurons, where defects in microtubule-based motility have been linked to neurological diseases. for example, lissencephaly is caused by mutations in the dynein-associated protein lis1. in this paper, using the long, highly polarized hyphae of the filamentous fungus aspergillus nidulans, we show that three morphologically and functionall ...201222711696
putative calcium channels ccha and mida play the important roles in conidiation, hyphal polarity and cell wall components in aspergillus nidulans.although the high affinity ca(2+) channel, cch1, and its subunit mid1 have been investigated and evaluated in yeast and some of filamentous fungi, little is known about the function of their homologs in the aspergilli. here, we have functionally characterized the yeast homologs, ccha and mida, in aspergillus nidulans using conditional and null deletion mutants. ccha and mida not only have functional benefits of fast growth, which is consistent with cch1 and mid1 in yeast, but also have unique an ...201223071589
involvement of protein kinase c in the suppression of apoptosis and in polarity establishment in aspergillus nidulans under conditions of heat stress.the pkca gene, which encodes a protein kinase c (pkc) in the filamentous fungus aspergillus nidulans, is essential for its viability. however, little is known about its functions. to address this issue, we constructed and characterized temperature-sensitive mutants of pkca. the conidia of these mutants swelled slightly and exhibited apoptotic phenotypes at 42°c. the apoptotic phenotypes were suppressed by an osmotic stabilizer. under these conditions, the conidia swelled extensively and did not ...201223209763
the role, interaction and regulation of the velvet regulator velb in aspergillus nidulans.the multifunctional regulator velb physically interacts with other velvet regulators and the resulting complexes govern development and secondary metabolism in the filamentous fungus aspergillus nidulans. here, we further characterize velb's role in governing asexual development and conidiogenesis in a. nidulans. in asexual spore formation, velb deletion strains show reduced number of conidia, and decreased and delayed mrna accumulation of the key asexual regulatory genes brla, abaa, and vosa. o ...201223049895
genetic control of asexual sporulation in filamentous fungi.asexual sporulation (conidiation) in the ascomycetous filamentous fungi involves the formation of conidia, formed on specialized structures called conidiophores. conidiation in filamentous fungi involves many common themes including spatial and temporal regulation of gene expression, specialized cellular differentiation, intra-/inter-cellular communications, and response to environmental factors. the commencement, progression and completion of conidiation are regulated by multiple positive and n ...201223092920
genetic analysis of the arabidopsis protein kinases map3kε1 and map3kε2 indicates roles in cell expansion and embryo development.map3kε1 and map3kε2 are a pair of arabidopsis thaliana genes that encode protein kinases related to cdc7p from saccharomyces cerevisiae. we have previously shown that the map3kε1;map3kε2 double-mutant combination causes pollen lethality. in this study, we have used an ethanol-inducible promoter construct to rescue this lethal phenotype and create map3kε1(-/-);map3kε2(-/-) double-mutant plants in order to examine the function of these genes in the sporophyte. these rescued double-mutant plants ca ...201223087695
a pericentrin-related protein homolog in aspergillus nidulans plays important roles in nucleus positioning and cell polarity by affecting microtubule organization.pericentrin is a large coiled-coil protein in mammalian centrosomes that serves as a multifunctional scaffold for anchoring numerous proteins. recent studies have linked numerous human disorders with mutated or elevated levels of pericentrin, suggesting unrecognized contributions of pericentrin-related proteins to the development of these disorders. in this study, we characterized anpcpa, a putative homolog of pericentrin-related protein in the model filamentous fungus aspergillus nidulans, and ...201223087372
high abundance of serine/threonine-rich regions predicted to be hyper-o-glycosylated in the secretory proteins coded by eight fungal genomes.o-glycosylation of secretory proteins has been found to be an important factor in fungal biology and virulence. it consists in the addition of short glycosidic chains to ser or thr residues in the protein backbone via o-glycosidic bonds. secretory proteins in fungi frequently display ser/thr rich regions that could be sites of extensive o-glycosylation. we have analyzed in silico the complete sets of putatively secretory proteins coded by eight fungal genomes (botrytis cinerea, magnaporthe grise ...201222994653
phosphoribosyl pyrophosphate synthetase, as a suppressor of the seph mutation in aspergillus nidulans, is required for the proper timing of septation.timely cytokinesis/septation is essential for hyphal growth and conidiation in aspergillus nidulans. genetic analyses have identified that a. nidulans has components of the septum initiation network (sin) pathway; one of these, seph, is a key player for early events during cytokinesis. however, little is known about how the seph kinase cascade is regulated by other components. here, we demonstrate that the phosphoribosyl pyrophosphate synthetase family acts antagonistically against the sin so th ...201222994198
modeling, substrate docking, and mutational analysis identify residues essential for the function and specificity of a eukaryotic purine-cytosine ncs1 transporter.the recent elucidation of crystal structures of a bacterial member of the ncs1 family, the mhp1 benzyl-hydantoin permease from microbacterium liquefaciens, allowed us to construct and validate a three-dimensional model of the aspergillus nidulans purine-cytosine/h(+) fcyb symporter. the model consists of 12 transmembrane α-helical, segments (tmss) and cytoplasmic n- and c-tails. a distinct core of 10 tmss is made of two intertwined inverted repeats (tms1-5 and tms6-10) that are followed by two a ...201222969088
invasive fungal infection in chronic granulomatous disease: insights into pathogenesis and management.invasive fungal infections (ifis) remain a major cause of death in patients with chronic granulomatous disease (cgd). we discuss the new insights into the pathogenesis, diagnosis, prevention, and management of invasive fungal infections in patients with cgd.201222964947
multivariate phenotypic divergence due to the fixation of beneficial mutations in experimentally evolved lineages of a filamentous fungus.the potential for evolutionary change is limited by the availability of genetic variation. mutations are the ultimate source of new alleles, yet there have been few experimental investigations of the role of novel mutations in multivariate phenotypic evolution. here, we evaluated the degree of multivariate phenotypic divergence observed in a long-term evolution experiment whereby replicate lineages of the filamentous fungus aspergillus nidulans were derived from a single genotype and allowed to ...201223185601
saga complex components and acetate repression in aspergillus nidulans.alongside the well-established carbon catabolite repression by glucose and other sugars, acetate causes repression in aspergillus nidulans. mutations in crea, encoding the transcriptional repressor involved in glucose repression, also affect acetate repression, but mutations in creb or crec, encoding components of a deubiquitination system, do not. to understand the effects of acetate, we used a mutational screen that was similar to screens that uncovered mutations in crea, creb, and crec, excep ...201223173087
new insights into the biosynthesis of prenylated xanthones: xptb from aspergillus nidulans catalyses an o-prenylation of xanthones.gene-inactivation experiments have indicated that the putative prenyltransferase xptb from aspergillus nidulans was likely to be responsible for the prenylation of 1,7-dihydroxy-6-methyl-8-hydroxymethylxanthone. recently, it was suggested that this enzyme might also accept as substrate the benzophenone arugosin h, which is assumed to be a precursor of prenylated xanthones. in this study, five benzophenones and ten xanthones were incubated with purified recombinant xptb in the presence of dimethy ...201223150454
multi-copy genetic screen in aspergillus nidulans.with the completion of genomes of various aspergillus species, large-scale genome-wide expression studies can be carried out. genomics, however, is more powerful and efficient when combined with genetics. a multi-copy-based gain-of-function screen is a complementary method to loss-of-function genetic screen and can identify novel genes that may not be easily identifiable through loss-of-function-type screens. particularly, gain-of-function genetic screens would identify novel activators or repre ...201223065617
tools for manipulation of secondary metabolism pathways: rapid promoter replacements and gene deletions in aspergillus nidulans.targeted gene deletions and promoter replacements are proving to be a valuable tool for awakening and analyzing silent secondary metabolism gene clusters in aspergillus nidulans and, as molecular genetic methods for manipulating the genomes of other fungi are developed, they will likely be as valuable in those organisms. here we describe procedures for constructing dna fragments by pcr that can be used to replace genes or promoters quickly and on a large scale. we also describe transformation pr ...201223065614
the chemical identification and analysis of aspergillus nidulans secondary metabolites.filamentous fungi have long been recognized to be a rich source of secondary metabolites with potential medicinal applications. the recent genomic sequencing of several aspergillus species has revealed that many secondary metabolite gene clusters are apparently silent under standard laboratory conditions. several successful approaches have been utilized to upregulate these genes and unearth the corresponding natural products. a straightforward, reliable method to purify and characterize new meta ...201223065610
galx regulates the d-galactose oxido-reductive pathway in aspergillus niger.galactose catabolism in aspergillus nidulans is regulated by at least two regulators, galr and galx. in aspergillus niger only galx is present, and its role in d-galactose catabolism in this fungus was investigated. phenotypic and gene expression analysis of a wild type and a galx disruptant revealed that galx regulates the d-galactose oxido-reductive pathway, but not the leloir pathway in a. niger.201223063944
cell cycle regulation by the nek family of protein kinases.genetic screens for cell division cycle mutants in the filamentous fungus aspergillus nidulans led to the discovery of never-in-mitosis a (nima), a serine/threonine kinase that is required for mitotic entry. since that discovery, nima-related kinases, or neks, have been identified in most eukaryotes, including humans where eleven genetically distinct proteins named nek1 to nek11 are expressed. although there is no evidence that human neks are essential for mitotic entry, it is clear that several ...201223132929
improvement of gene targeting in aspergillus nidulans with excess non-homologous fragments.efficiency of gene targeting was increased more than 10-fold when an excess molar ratio of non-homologous fragments was added in the transformation of aspergillus nidulans. in the targeted transformants, integration of such fragments into the host chromosome was a rare event. hence, our approach proved practical in terms of producing successful targeting events without disturbing the host chromosomes.201223132572
microtubule-based transport in filamentous fungi.defects in microtubule-based transport are implicated in many neuropathologies. the filamentous fungi aspergillus nidulans and ustilago maydis are valuable models for studying transport owing to their yeast-like genetic and biochemical tractability and metazoan-like dependence on microtubule-based transport for cellular trafficking. in these organisms the role of microtubules in nuclear positioning is well studied, but recent work has expanded the range of cargos to include endosomes, messenger ...201223127389
investigation of in vivo protein interactions in aspergillus spores.understanding in vivo protein-protein interactions is critical to dissect precise functions of the regulatory proteins of fungal secondary metabolites. as many fungi differentially produce a diverse array of secondary metabolites during their lifecycle, it is important to understand the cell-type specific regulation of secondary metabolism. however, due to the difficulty of sample preparation of biologically active proteins in fungal spores, protein-protein interaction studies have been generall ...201223065622
identification of protein complexes from filamentous fungi with tandem affinity purification.fungal molecular biology has benefited from the enormous advances in understanding protein-protein interactions in prokaryotic or eukaryotic organisms of the past decade. tandem affinity purification (tap) allows the enrichment of native protein complexes from cell extracts under mild conditions. we codon-optimized tags and established tap, previously not applicable to filamentous fungi, for the model organism aspergillus nidulans. we could identify by this method the trimeric velvet complex vel ...201223065618
antifungal activity of extracellular hydrolases produced by autolysing aspergillus nidulans cultures.carbon-starving aspergillus nidulans cultures produce high activities of versatile hydrolytic enzymes and, among these, chib endochitinase and enga β-1,3-endoglucanase showed significant antifungal activity against various fungal species. double deletion of enga and chib diminished the antifungal activity of the fermentation broths and increased conidiogenesis and long-term viability of a. nidulans, but decreased the growth rate on culture media containing weak carbon sources. production of chib ...201223124755
reengineering an azaphilone biosynthesis pathway in aspergillus nidulans to create lipoxygenase inhibitors.sclerotiorin, an azaphilone polyketide, is a bioactive natural product known to inhibit 15-lipoxygenase and many other biological targets. to readily access sclerotiorin and analogs, we developed a 2-3 step semisynthetic route to produce a variety of azaphilones starting from an advanced, putative azaphilone intermediate (5) overproduced by an engineered strain of aspergillus nidulans. the inhibitory activities of the semisynthetic azaphilones against 15-lipoxygenase were evaluated with several ...201222296232
an aspergillus nidulans bzip response pathway hardwired for defensive secondary metabolism operates through aflr.the eukaryotic bzip transcription factors are critical players in organismal response to environmental challenges. in fungi, the production of secondary metabolites (sms) is hypothesized as one of the responses to environmental insults, e.g. attack by fungivorous insects, yet little data to support this hypothesis exists. here we establish a mechanism of bzip regulation of sms through rsma, a recently discovered yap-like bzip protein. rsma greatly increases sm production by binding to two sites ...201222283524
functional analysis of fara transcription factor in the regulation of the genes encoding lipolytic enzymes and hydrophobic surface binding protein for the degradation of biodegradable plastics in aspergillus oryzae.fara is a zn(ii)(2)cys(6) transcription factor which upregulates genes required for growth on fatty acids in filamentous fungi like aspergillus nidulans. fara is also highly similar to the cutinase transcription factor ctf1α of fusarium solani which binds to the cutinase gene promoter in this plant pathogen. this study determines whether fara transcriptional factor also works in the regulation of genes responsible for the production of cutinase for the degradation of a biodegradable plastic, pol ...201222280964
signaling the induction of sporulation involves the interaction of two secondary metabolites in aspergillus nidulans.when growing aspergillus nidulans hyphae encounter the atmosphere, they initiate a morphogenetic program leading to the production of spores. mutants that are defective in the flug gene fail to undergo sporulation because they lack an endogenous diffusible factor that purportedly accumulates on aerial hyphae, thus signaling the initiation of development. in this study, the defect could be reversed by adding culture extracts from a wild-type strain onto a mutant colony. moreover, a bioassay-guide ...201222234162
genetics of polyketide metabolism in aspergillus nidulans.secondary metabolites are small molecules that show large structural diversity and a broad range of bioactivities. some metabolites are attractive as drugs or pigments while others act as harmful mycotoxins. filamentous fungi have the capacity to produce a wide array of secondary metabolites including polyketides. the majority of genes required for production of these metabolites are mostly organized in gene clusters, which often are silent or barely expressed under laboratory conditions, making ...201224957370
the role of flotillin floa and stomatin stoa in the maintenance of apical sterol-rich membrane domains and polarity in the filamentous fungus aspergillus nidulans.apical sterol-rich plasma membrane domains (srds), which can be viewed using the sterol-binding fluorescent dye filipin, are gaining attention for their important roles in polarized growth of filamentous fungi. the microdomain scaffolding protein flotillin/reggie and related stomatin were thought to be good candidates involved in the formation of srds. here, we show that the flotillin/reggie orthologue floa tagged with gfp localized as stable dots along the plasma membrane except hyphal tips. de ...201222329814
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