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regulation of development in aspergillus nidulans and aspergillus fumigatus.members of the genus aspergillus are the most common fungi and all reproduce asexually by forming long chains of conidiospores (or conidia). the impact of various aspergillus species on humans ranges from beneficial to harmful. for example, several species including aspergillus oryzae and aspergillus niger are used in industry for enzyme production and food processing. in contrast, aspergillus flavus produce the most potent naturally present carcinogen aflatoxins, which contaminate various plant ...201023956662
strategies of xylanase supplementation for an efficient saccharification and cofermentation process from pretreated wheat straw.ethanol production from lignocellulosic raw materials includes a pretreatment step before enzymatic hydrolysis (eh). pretreated substrates contain complex hemicelluloses in the solid fraction that can protect the cellulose from enzymatic attack. in addition, soluble xylooligomers are contained in the pretreated materials and may have an inhibitory effect on cellulase activity. in this context, several approaches for xylanase supplementation have been studied to increase eh yields. in this study, ...201121567993
characterization of melanin pigment produced by aspergillus nidulans.although most of the ascomycetes present dhn-melanin, some reports suggest that a. nidulans does not produce this type of melanin. in this study, we analyzed the pigment extracted from highly melanized strains (mel1 and mel2) of aspergillus nidulans to determine the type of melanin present in this fungus. our results showed that the pigment produced by mel1 and mel2 mutants possesses physical and chemical properties and uv- and ir-spectra very similar to synthetic dopa-melanin. the characterizat ...201122805928
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
fungal photobiology: a synopsis.fungi respond and adapt to many environmental signals including light. the photobiology of fungi has been extensively investigated, but in recent years the identification of the first fungal photoreceptor, wc-1 in the ascomycete neurospora crassa, and the discovery that similar photoreceptors are required for photoreception in other ascomycete, basidiomycete and zygomycete fungi has allowed the molecular characterization of light reception and the early steps of signal transduction in a number o ...201122679584
allergens/antigens, toxins and polyketides of important aspergillus species.the medical, agricultural and biotechnological importance of the primitive eukaryotic microorganisms, the fungi was recognized way back in 1920. among various groups of fungi, the aspergillus species are studied in great detail using advances in genomics and proteomics to unravel biological and molecular mechanisms in these fungi. aspergillus fumigatus, aspergillus flavus, aspergillus niger, aspergillus parasiticus, aspergillus nidulans and aspergillus terreus are some of the important species r ...201122468035
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
definition and characterization of enzymes for maximal biocatalytic solubilization of prebiotic polysaccharides from potato pulp.potato pulp is a high-volume co-processing product resulting from industrial potato starch manufacturing. potato pulp is particularly rich in pectin, notably galactan branched rhamnogalacturonan i polysaccharides, which are highly bifidogenic when solubilized. the objective of the present study was to characterize and compare four homogalacturonan degrading enzymes capable of catalyzing the required solubilization of these pectinaceous polysaccharides from potato pulp in a 1 min reaction. an add ...201122112514
studies on differential nuclear translocation mechanism and assembly of the three subunits of the arabidopsis thaliana transcription factor nf-y.the eukaryotic transcription factor nf-y consists of three subunits (a, b, and c), which are encoded in arabidopsis thaliana in multigene families consisting of 10, 13, and 13 genes, respectively. in principle, all potential combinations of the subunits are possible for the assembly of the heterotrimeric complex. we aimed at assessing the probability of each subunit to participate in the assembly of nf-y. the evaluation of physical interactions among all members of the nf-y subunit families indi ...201122199235
recombinant production and characterisation of two related gh5 endo-β-1,4-mannanases from aspergillus nidulans fgsc a4 showing distinctly different transglycosylation capacity.the glycoside hydrolase family 5 (gh5) endo-β-1,4-mannanases mana and manc from aspergillus nidulans fgsc a4 were produced in pichia pastoris x33 and purified in high yields of 120 and 145mg/l, respectively, from the culture supernatants. both enzymes showed increasing catalytic efficiency (k(cat)/k(m)) towards β-1,4 manno-oligosaccharides with the degree of polymerisation (dp) from 4 to 6 and also hydrolysed konjac glucomannan, guar gum and locust bean gum galactomannans. manc had up to two-fol ...201121867780
nuclear transporters in a multinucleated organism: functional and localization analyses in aspergillus nidulans.nuclear transporters mediate bidirectional macromolecule traffic through the nuclear pore complex (npc), thus participating in vital processes of eukaryotic cells. a systematic functional analysis in aspergillus nidulans permitted the identification of 4 essential nuclear transport pathways of a hypothetical number of 14. the absence of phenotypes for most deletants indicates redundant roles for these nuclear receptors. subcellular distribution studies of these carriers show three main distribut ...201121880896
the length of adaptive walks is insensitive to starting fitness in aspergillus nidulans.adaptation involves the successive substitution of beneficial mutations by selection, a process known as an adaptive walk. gradualist models of adaptation, which assume that all mutations are small relative to the distance to a fitness optimum, predict that adaptive walks should be longer when the founding genotype is less well adapted. more recent work modeling adaptation as a sequence of moves in phenotype or genotype space predicts, by contrast, much shorter adaptive walks irrespective of the ...201122023575
conserved and specific responses to hypoxia in aspergillus oryzae and aspergillus nidulans determined by comparative transcriptomics.hypoxia imposes stress on filamentous fungi that require oxygen to proliferate. global transcription analysis of aspergillus oryzae grown under hypoxic conditions found that the expression of about 50% of 4,244 affected genes was either induced or repressed more than 2-fold. a comparison of these genes with the hypoxically regulated genes of aspergillus nidulans based on their predicted amino acid sequences classified them as bi-directional best hit (bbh), one-way best hit (extra homolog, eh), a ...201122170104
a new class of imp dehydrogenase with a role in self-resistance of mycophenolic acid producing fungi.many secondary metabolites produced by filamentous fungi have potent biological activities, to which the producer organism must be resistant. an example of pharmaceutical interest is mycophenolic acid (mpa), an immunosuppressant molecule produced by several penicillium species. the target of mpa is inosine-5'-monophosphate dehydrogenase (impdh), which catalyses the rate limiting step in the synthesis of guanine nucleotides. the recent discovery of the mpa biosynthetic gene cluster from penicilli ...201121923907
wild-type mic distributions and epidemiological cutoff values for amphotericin b and aspergillus spp. for the clsi broth microdilution method (m38-a2 document).although clinical breakpoints have not been established for mold testing, epidemiological cutoff values (ecvs) are available for aspergillus spp. versus the triazoles and caspofungin. wild-type (wt) mic distributions (organisms in a species-drug combination with no acquired resistance mechanisms) were defined in order to establish ecvs for six aspergillus spp. and amphotericin b. two sets (clsi/eucast broth microdilution) of available mics were evaluated: those for a. fumigatus (3,988/833), a. f ...201121876047
identification of the galactitol dehydrogenase, ladb, that is part of the oxido-reductive d-galactose catabolic pathway in aspergillus niger.for the catabolism of d-galactose three different metabolic pathways have been described in filamentous fungi. apart from the leloir pathway and the oxidative pathway, there is an alternative oxido-reductive pathway. this oxido-reductive pathway has similarities to the metabolic pathway of l-arabinose, and in trichoderma reesei (hypocrea jecorina) and aspergillus nidulans the same enzyme is employed for the oxidation of l-arabitol and galactitol. here we show evidence that in aspergillus nigerl- ...201122155165
in vivo roles of the basic domain of dynactin p150 in microtubule plus-end tracking and dynein function.microtubule (mt) plus-end-tracking proteins accumulate at mt plus ends for various cellular functions, but their targeting mechanisms are not fully understood (akhmanova a and steinmetz mo. tracking the ends: a dynamic protein network controls the fate of microtubule tips. nat rev mol cell biol 2008;9:309-322.). here, we tested in the filamentous fungus aspergillus nidulans the requirement for plus-end localization of dynactin p150, a protein essential for dynein function. deletion of the n-term ...201122106867
new resources for functional analysis of omics data for the genus aspergillus.detailed and comprehensive genome annotation can be considered a prerequisite for effective analysis and interpretation of omics data. as such, gene ontology (go) annotation has become a well accepted framework for functional annotation. the genus aspergillus comprises fungal species that are important model organisms, plant and human pathogens as well as industrial workhorses. however, go annotation based on both computational predictions and extended manual curation has so far only been availa ...201121974739
Putative stress sensors WscA and WscB are involved in hypo-osmotic and acidic pH stress tolerance in Aspergillus nidulans.Wsc proteins have been identified in fungi and are believed to be stress sensors in the cell wall integrity (CWI) signaling pathway. In this study, we characterized the sensor orthologs WscA and WscB in Aspergillus nidulans. Using hemagglutinin-tagged WscA and WscB, we showed both Wsc proteins to be N- and O-glycosylated and localized in the cell wall and membrane, implying that they are potential cell surface sensors. The wscA disruptant (?wscA) strain was characterized by reduced colony and co ...201121926329
association between indoor fungi in delhi homes and sensitization in children with respiratory allergy.indoor fungi are potential sensitizing agents in children and their detection and quantification in indoor air are important in the diagnosis and environmental management of fungal allergies. the objective of this investigation was to assess the prevalence of fungal allergies in children in delhi and to study the association between mold counts in the homes of children and their sensitization to respective fungal extracts. fungal concentrations and seasonality were studied at two-week intervals ...201122103346
farnesol-induced cell death in the filamentous fungus aspergillus nidulans.foh (farnesol), a non-sterol isoprenoid produced by dephosphorylation of farnesyl pyrophosphate, has been shown to inhibit proliferation and induce apoptosis. we have been using aspergillus nidulans and foh as a model system and cell death stimulus, respectively, aiming to understand by which means filamentous fungi are driven towards cell death. here, we review some of our findings about foh-induced cell death in a. nidulans.201121936849
Aspergillus Myosin-v supports polarized growth in the absence of microtubule-based transport.In the filamentous fungus Aspergillus nidulans, both microtubules and actin filaments are important for polarized growth at the hyphal tip. Less clear is how different microtubule-based and actin-based motors work together to support this growth. Here we examined the role of myosin-V (MYOV) in hyphal growth. MYOV-depleted cells form elongated hyphae, but the rate of hyphal elongation is significantly reduced. In addition, although wild type cells without microtubules still undergo polarized grow ...201122194856
Heterochromatin influences the secondary metabolite profile in the plant pathogen Fusarium graminearum.Chromatin modifications and heterochromatic marks have been shown to be involved in the regulation of secondary metabolism gene clusters in the fungal model system Aspergillus nidulans. We examine here the role of HEP1, the heterochromatin protein homolog of Fusarium graminearum, for the production of secondary metabolites. Deletion of Hep1 in a PH-1 background strongly influences expression of genes required for the production of aurofusarin and the main tricothecene metabolite DON. In the Hep1 ...201122100541
Disruption of Trichoderma reesei cre2, encoding an ubiquitin C-terminal hydrolase, results in increased cellulase activity.ABSTRACT:201122070776
structural analysis of fungal cerebrosides.of the ceramide monohexosides (cmhs), gluco- and galactosyl-ceramides are the main neutral glycosphingolipids expressed in fungal cells. their structural determination is greatly dependent on the use of mass spectrometric techniques, including fast atom bombardment-mass spectrometry, electrospray ionization, and energy collision-induced dissociation mass spectrometry. nuclear magnetic resonance has also been used successfully. such a combination of techniques, combined with classical analytical ...201122164155
Isolation and characterization of self-fertile suppressors from the sterile nsdD deletion mutant of Aspergillus nidulans.To identify downstream and/or interactive factors of the nsdD gene, which encodes a positive regulator of sexual development of Aspergillus nidulans, suppressor mutants displaying a self-fertile phenotype were isolated from a sterile nsdD deletion mutant. At least five different loci (sndA-E) were identified and genetically analyzed. In the nsdD (+) background, most of the suppressors showed a marked increment of sexual development, even under the stress conditions that n ...201122203574
the velvet gene, fgve1, affects fungal development and positively regulates trichothecene biosynthesis and pathogenicity in fusarium graminearum.trichothecenes are a group of toxic secondary metabolites produced mainly by fusarium graminearum (teleomorph: gibberella zeae) during the infection of crop plants, including wheat, maize, barley, oats, rye and rice. some fungal genes involved in trichothecene biosynthesis have been shown to encode regulatory proteins. however, the global regulation of toxin biosynthesis is still enigmatic. in addition to the production of secondary metabolites belonging to the trichothecene family, f. graminear ...201122013911
[general epidemiology of invasive fungal disease.]invasive mycoses associated with high morbidity and mortality rates are increasing among immunocompromised or severely ill patients. candida, cryptococcus, pneumocystis and aspergillus are most prevalent agents with varying distribution as regards geography, patient condition and hospital units. the latest multicentre candidaemia survey conducted in spain, showed c. albicans as the most frequently isolated species followed by c. parapsilosis, c. glabrata, c. tropicalis and c. krusei in contrast ...201122079232
constitutive expression, purification and characterization of a phosphoglucomutase from fusarium oxysporum.the phosphoglucomutase gene from a wild type fusarium oxysporum strain (f3), was homologously expressed, under the control of the constitutive promoter of gpda of aspergillus nidulans. the transformant produced elevated levels of phosphoglucomutase activity compared to the wild type, a fact that facilitated the subsequent purification procedure. the enzyme (fopgm) was purified to homogeneity applying three anion exchange and one gel filtration chromatography steps. the native enzyme revealed a m ...201122112903
heterologous expression system in aspergillus oryzae for fungal biosynthetic gene clusters of secondary metabolites.fungal secondary metabolites have been considered promising resources in the search for novel bioactive compounds. given the high potential of fungi as genetic resources, it is essential to find an efficient way to link biosynthetic genes to the product in a heterologous system, because many genes for the secondary metabolite in the original strain are silent under standard laboratory conditions. in a previous study, we constructed a heterologous expression system for a biosynthetic gene cluster ...201122083274
contributions of the peroxisome and β-oxidation cycle to biotin synthesis in fungi.the first step in the synthesis of the bicyclic rings of d-biotin is mediated by 8-amino-7-oxononanoate (aon) synthase, which catalyzes the decarboxylative condensation of l-alanine and pimelate thioester. we found that the aspergillus nidulans aon synthase, encoded by the biof gene, is a peroxisomal enzyme with a type 1 peroxisomal targeting sequence (pts1). localization of aon to the peroxisome was essential for biotin synthesis because expression of a cytosolic aon variant or deletion of pexe ...201121998305
rescue of aspergillus nidulans severely debilitating null mutations in escrt-0, i, ii and iii genes by inactivation of a salt-tolerance pathway allows examination of escrt gene roles in ph signalling.the aspergillus pal pathway hijacks escrt proteins into ambient ph signalling complexes. we show that components of escrt-0, escrt-i, escrt-ii and escrt-iii are nearly essential for growth, precluding assessment of null mutants for ph signalling or trafficking. this severely debilitating effect is rescued by loss-of-function mutations in two cation tolerance genes, one of which, slta, encodes a transcription factor whose inactivation promotes hypervacuolation. exploiting a conditional expression ...201122135362
Polyphasic characterization of "Aspergillus nidulans var. roseus" ATCC 58397.Polyphasic characterization of the echinocandin B producer Aspergillus nidulans var. roseus ATCC 58397 strain was carried out to elucidate its taxonomical status. According to its carbon source utilization and secondary metabolite spectrum as well as the partial ß-tubulin, calmodulin, and ?-actin gene sequences, A. nidulans var. roseus belongs to the Emericella rugulosa species. Auxotroph mutants of A. nidulans var. roseus ATCC 58397 and E. rugulosa CBS 171.71 and CBS 133.60 formed stable hetero ...201121858538
engineering hydrophobin dewa to generate surfaces that enhance adhesion of human but not bacterial cells.hydrophobins are fungal proteins with the ability to form immunologically inert membranes of high stability, properties that makes them attractive candidates for orthopaedic implant coatings. cell adhesion on the surface of such implants is necessary for better integration with the neighbouring tissue; however, hydrophobin surfaces do not mediate cell adhesion. the aim of this project was therefore to investigate whether the class i hydrophobin dewa from aspergillus nidulans can be functionalize ...201122154865
complex mechanisms regulate developmental expression of the mata (hmg) mating type gene in homothallic aspergillus nidulans.sexual reproduction is a fundamental developmental process that allows for genetic diversity through the control of zygote formation, recombination, and gametogenesis. the correct regulation of these events is paramount. sexual reproduction in filamentous fungi, including mating strategy (self-fertilization/homothallism or outcrossing/heterothallism), is determined by the expression of mating type genes at mat loci. aspergillus nidulans mata encodes a critical regulator that is a fungal ortholog ...201121868608
cytotoxic pheofungins from an engineered fungus impaired in posttranslational protein modification. 201121913294
the anisin1 gene encodes a defensin-like protein and supports the fitness of aspergillus nidulans.in the genome of aspergillus nidulans, a defensin-like protein, anisin1, was annotated with high homology to the mosquito defensin aadefa1. so far, no studies exist on defensins from filamentous ascomycetes. therefore, we characterized the anisin1 gene in a. nidulans and generated a deletion mutant, which suffered from a defect in mitospore development and produced less conidia at 42°c compared to the reference strain. in surface cultures of a. nidulans wild type, the anisin1 expression correlat ...201122113351
Culture-positive invasive aspergillosis in a medical center in Taiwan, 2000-2009.We reviewed 776 patients who were culture positive for Aspergillus species at the hospital from 2000 to 2009. The isolates were collected for species identification by oligonucleotide hybridization and sequence analysis. A total of 96 cases of proven or probable IA were identified according to published criteria. The incidence of IA has increased significantly during the study period. Aspergillus fumigatus and A. flavus (41.7% each) were equally prevalent causative species. IA due to unusual spe ...201121997774
A strong promoter, PMagpd, provides a tool for high gene expression in entomopathogenic fungus, Metarhizium acridum.A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter (PMagpd) was obtained from Metarhizium acridum and its active region analyzed by 5'-deletion strategy using ß-glucuronidase (GUS) as a reporter. Sequence analysis revealed that typical regulatory elements of PMagpd were included in the 1.7 kb region upstream of the start codon of the Magpd gene. Deletion of the region from -1,691 bp to -1,463 bp, where the gpd box is harbored, did not significantly affect the PMagpd activity. Deletio ...201122109936
Invasive mold infections in chronic granulomatous disease: a 25-year retrospective survey.Invasive fungal infection (IFI) represents a life-threatening condition for patients with chronic granulomatous disease (CGD) and causes one-third of deaths in this population. This study offers a descriptive review of invasive mold infection (mIFI) in children with CGD over an extended period of time.201122080130
the vea gene of the pine needle pathogen dothistroma septosporum regulates sporulation and secondary metabolism.fungi possess genetic systems to regulate the expression of genes involved in complex processes such as development and secondary metabolite biosynthesis. the product of the velvet gene vea, first identified and characterized in aspergillus nidulans, is a key player in the regulation of both of these processes. since its discovery and characterization in many aspergillus species, vea has been found to have similar functions in other fungi, including the dothideomycete mycosphaerella graminicola. ...201122227160
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
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
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
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
effect of endoxylanase and a-l-arabinofuranosidase supplementation on the enzymatic hydrolysis of steam exploded wheat straw.the cost and hydrolytic efficiency of enzymes are major factors that restrict the commercialization of the bioethanol production process from lignocellulosic biomass. hemicellulases and other accessory enzymes are becoming crucial to increase enzymatic hydrolysis (eh) yields at low cellulase dosages. the aim of this work was to evaluate the effect of two recombinant hemicellulolytic enzymes on the eh of steam pretreated wheat straw. pretreatments at two severity conditions were performed and the ...201121262567
independent duplications of a-amylase in different strains of aspergillus oryzae.aspergillus oryzae is a filamentous fungus that has arisen through the ancient domestication of aspergillus flavus for making traditional oriental foods and beverages. in the many centuries a. oryzae has been used for fermenting the starch in rice to simple sugars, it has undergone selection for increased secretion of starch-degrading enzymes. in particular, all a. oryzae strains investigated thus far have two or more copies of a gene encoding a-amylase, whereas a. flavus has only one. here we i ...201121277379
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
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
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
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
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
homologous overexpression of xylanase in fusarium oxysporum increases ethanol productivity during consolidated bioprocessing (cbp) of lignocellulosics.in an effort to increase ethanol productivity during the consolidated bioprocessing (cbp) of lignocellulosics by fusarium oxysporum, we attempted the constitutive homologous overexpression of one of the key process enzymes, namely an endo-xylanase. the endo-β-1,4-xylanase 2 gene was incorporated into the f. oxysporum genome under the regulation of the gpda promoter of aspergillus nidulans. the transformation was effected through agrobacterium tumefaciens and resulted in 12 transformants, two of ...201121237221
maximal release of highly bifidogenic soluble dietary fibers from industrial potato pulp by minimal enzymatic treatment.potato pulp is a poorly utilized, high-volume co-processing product resulting from industrial potato starch manufacturing. potato pulp mainly consists of the tuber plant cell wall material and is particularly rich in pectin, notably galactan branched rhamnogalacturonan i type pectin which has previously been shown to exhibit promising properties as dietary fiber. the objective of this study was to solubilize dietary fibers from potato pulp by a one-step minimal treatment procedure and evaluate t ...201121253720
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
onsite bio-detoxification of steam-exploded corn stover for cellulosic ethanol production.in the process of ethanol production from steam-exploded corn stover (secs), a cellulose-degradation strain of aspergillus nidulans (flz10) was investigated whether it could remove the inhibitors released from steam exploded pretreatment , and thereby be used for biological detoxification on saccharomycescerevisiae. the results showed that flz10 removed 75.2% formic acid, 53.6% acetic acid, and 100% hydroxymethyl furfural (5-hmf) and furfural from the hydrolysate washed from secs after 72h culti ...201121334878
quantifying the importance of galactofuranose in aspergillus nidulans hyphal wall surface organization by atomic force microscopy.the fungal wall mediates cell-environment interactions. galactofuranose (galf), the five-member ring form of galactose, has a relatively low abundance in aspergillus walls yet is important for fungal growth and fitness. aspergillus nidulans strains deleted for galf biosynthesis enzymes ugea (udp-glucose-4-epimerase) and ugma (udp-galactopyranose mutase) lacked immunolocalizable galf, had growth and sporulation defects, and had abnormal wall architecture. we used atomic force microscopy and force ...201121335527
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
immunomodulatory and therapeutic potential of a mycelial lectin from aspergillus nidulans.lectins bind to surface receptors on target cells, and activate a cascade of events, eventually leading to altered immune status of host. the immunomodulatory potential of purified lectin from aspergillus nidulans was evaluated in swiss albino mice treated intraperitoneally with seven different doses of purified lectin. lectin prevented bsa-induced arthus reaction and systemic anaphylaxis. the enhanced functional ability of macrophages was evident from respiratory burst activity and nitric oxide ...201121590306
characterisation of anbest1, a functional anion channel in the plasma membrane of the filamentous fungus, aspergillus nidulans.two distant homologues of the bestrophin gene family have been identified in the filamentous fungus, aspergillus nidulans (anbest1 and anbest2). anbest1 was functionally characterised using the patch clamp technique and was shown to be an anion selective channel permeable to citrate. furthermore, anbest1 restored the growth of the pdr12δ yeast mutant on inhibitory concentrations of extracellular propionate, benzoate and sorbate, also consistent with carboxylated organic anion permeation of anbes ...201121596151
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
structure and activity of aspergillus nidulans copper amine oxidase.aspergillus nidulans amine oxidase (anao) has the unusual ability among the family of copper and trihydroxyphenylalanine quinone-containing amine oxidases of being able to oxidize the amine side chains of lysine residues in large peptides and proteins. we show here that in common with the related enzyme from the yeast pichia pastoris, anao can promote the cross-linking of tropoelastin and oxidize the lysine residues in α-casein proteins and tropoelastin. the crystal structure of anao, the first ...201121604787
kinetics of cyclobutane thymine dimer splitting by dna photolyase directly monitored in the uv.cpd photolyase uses light to repair cyclobutane pyrimidine dimers (cpds) formed between adjacent pyrimidines in uv-irradiated dna. the enzyme harbors an fad cofactor in fully reduced state (fadh(-)). the cpd repair mechanism involves electron transfer from photoexcited fadh(-) to the cpd, splitting of its intradimer bonds, and electron return to restore catalytically active fadh(-). the two electron transfer processes occur on time scales of 10(-10) and 10(-9) s, respectively. until now, cpd spl ...201121606324
osteomyelitis due to aspergillus species in chronic granulomatous disease: an update of the literature.chronic granulomatous disease (cgd) is a rare inherited disorder characterised by inability of phagocytes to kill catalase-positive organisms including certain fungi. aspergillus species are the most frequent fungal pathogens. this study is a systematic review of the reported cases of osteomyelitis due to aspergillus species in cgd patients. retrospective analysis of 46 osteomyelitis cases caused by aspergillus species in 43 cgd patients (three females) published in the english literature (pubme ...201121615532
autophagy induced by rapamycin and carbon-starvation have distinct proteome profiles in aspergillus nidulans.it is hypothesized that autophagy, a global catabolic pathway which is highly conserved from yeast to man, plays an important role in many bioprocesses. though autophagy is known to be induced by either nutrient starvation or treatment with the drug rapamycin, it is not clear whether the two modes of induction have the same long term impact in the cell, particularly in the biotechnologically important filamentous fungi. here, we compare the overall proteomes from the carbon-starved (g-) and rapa ...201121618477
chronic granulomatous disease of childhood: an unusual cause of recurrent uncommon infections in a 61-year-old man.chronic granulomatous disease (cgd) is a rare congenital immunodeficiency that affects 1 : 250 000 of the population, which is characterized by recurrent bacterial and fungal infections and by granuloma formation. we investigated a 61-year-old man presented with a 20-year history of a relapsing skin rash appearing as mildly pruritic and erythematous plaques affecting various body regions. cutaneous biopsies were taken and sent for histology and tissue culture. leucocyte function was assessed by ...201121623884
regulation of conidiation by light in aspergillus nidulans.light regulates several aspects of the biology of many organisms, including the balance between asexual and sexual development in some fungi. to understand how light regulates fungal development at the molecular level we have used aspergillus nidulans as a model. we have performed a genome-wide expression analysis that has allowed us to identify more than 400 genes upregulated, and more than 100 genes downregulated by light in developmentally competent mycelium. among the upregulated genes were ...201121624998
on the role of microtubules, cell end markers, and septal microtubule organizing centres on site selection for polar growth in aspergillus nidulans.tip growth of filamentous fungi depends on continuous polarized growth and requires the actin and microtubule (mt) cytoskeleton. cortical proteins at polarity sites, also known as cell end markers, play important roles in polarity maintenance. deletion of the cell end marker teaa results in zigzag hyphal morphologies, which is contrary to the normal rectilinear growth pattern. here we studied the role of teaa and mts in the establishment of polarity during tip growth of aspergillus nidulans, inc ...201121640315
role of nitric oxide and flavohemoglobin homologous genes in aspergillus nidulans sexual development and mycotoxin production.flavohemoglobins are widely distributed in both prokaryotes and eukaryotes. these proteins are involved in reducing nitric oxide levels. deletion of the aspergillus nidulans flavohemoglobin gene fhba induced sexual development and decreased sterigmatocystin production. supplementation with a nitric oxide-releasing compound promoted cleistothecial formation and increased nsdd and stea expression, indicating that nitric oxide induces sexual development. this is the first study on the effect of nit ...201121642398
regulated inactivation of the spindle assembly checkpoint without functional mitotic spindles.the spindle assembly checkpoint (sac) arrests mitosis until bipolar attachment of spindle microtubules to all chromosomes is accomplished. however, when spindle formation is prevented and the sac cannot be satisfied, mammalian cells can eventually overcome the mitotic arrest while the checkpoint is still activated. we find that aspergillus nidulans cells, which are unable to satisfy the sac, inactivate the checkpoint after a defined period of mitotic arrest. such sac inactivation allows normal n ...201121642954
analysis of aspergillus nidulans germination, initial growth and carbon source response by flow cytometry.in this work, flow cytometry was utilized to analyze the initial vegetative growth of the model fungus aspergillus nidulans as measured by the number of events increasing size and internal complexity. it was established the ideal parameters for the analysis of conidial populations, whose growth was followed after germination in glucose or sucrose. while glucose in culture increased growth several magnitudes in comparison to control cultures in saline, growth was less intense in cultures amended ...201121656795
coordination of secondary metabolism and development in fungi: the velvet family of regulatory proteins.filamentous fungi produce a number of small bioactive molecules as part of their secondary metabolism ranging from benign antibiotics such as penicillin to threatening mycotoxins such as aflatoxin. secondary metabolism can be linked to fungal developmental programs in response to various abiotic or biotic external triggers. the velvet family of regulatory proteins plays a key role in coordinating secondary metabolism and differentiation processes such as asexual or sexual sporulation and sclerot ...201121658084
a genome-wide polyketide synthase deletion library uncovers novel genetic links to polyketides and meroterpenoids in aspergillus nidulans.fungi possess an advanced secondary metabolism that is regulated and coordinated in a complex manner depending on environmental challenges. to understand this complexity, a holistic approach is necessary. we initiated such an analysis in the important model fungus aspergillus nidulans by systematically deleting all 32 individual genes encoding polyketide synthases. wild-type and all mutant strains were challenged on different complex media to provoke induction of the secondary metabolism. screen ...201121658102
microtubule dynamics in mitosis in aspergillus nidulans.mitosis in aspergillus nidulans is very rapid, requiring less than 5min at 37°c in germlings (bergen and morris, 1983). in this time the cytoplasmic microtubules (mts) must disassemble, the mitotic spindle assemble, function and disassemble, and cytoplasmic mts reassemble. it follows that cytoplasmic mts must be extremely dynamic in this period and we were interested, in particular, in examining the processes of mt disassembly in prophase and reassembly in anaphase and telophase. we observed a d ...201121807107
dynamics and mechanism of cyclobutane pyrimidine dimer repair by dna photolyase.photolyase uses blue light to restore the major ultraviolet (uv)-induced dna damage, the cyclobutane pyrimidine dimer (cpd), to two normal bases by splitting the cyclobutane ring. our earlier studies showed that the overall repair is completed in 700 ps through a cyclic electron-transfer radical mechanism. however, the two fundamental processes, electron-tunneling pathways and cyclobutane ring splitting, were not resolved. here, we use ultrafast uv absorption spectroscopy to show that the cpd sp ...201121804035
the aspergillus nidulans cenp-e kinesin kipa is able to dimerize and to move processively along microtubules.kinesin molecular motors serve a variety of cellular functions usually in dynamic processes. one characteristic feature of many kinesins is their atp-dependent processive movement along polymerized microtubules. however, many kinesins work as stationary polymerases or depolymerases. therefore, it needs to be determined for each motor, whether it moves processively along microtubules or not. the schizosaccharomyces pombe kinesin-7, tea2, has been shown to be involved in cell end marker transporta ...201121785949
nudc is required for interkinetic nuclear migration and neuronal migration during neocortical development.nudc is a highly conserved protein necessary for cytoplasmic dynein-mediated nuclear migration in aspergillus nidulans. nudc interacts genetically with aspergillus nudf and physically with its mammalian orthologue lis1, which is crucial for nuclear and neuronal migration during brain development. to test for related roles for nudc, we performed in utero electroporation into embryonic rat brain of cdnas encoding shrnas as well as wild-type and mutant forms of nudc. we show here that nudc, like li ...201121771589
phosphatidylinositol phospholipase c mediates carbon sensing and vegetative nuclear duplication rates in aspergillus nidulans.in this work, we disrupted one of three putative phosphatidylinositol phospholipase c genes of aspergillus nidulans and studied its effect on carbon source sensing linked to vegetative mitotic nuclear division. we showed that glucose does not affect nuclear division rates during early vegetative conidial germination (6-7 h) in either the wild type or the plca-deficient mutant. only after 8 h of cultivation on glucose did the mutant strain present some decrease in nuclear duplication. however, de ...201121770720
[performance of locked nucleic acid probe real-time polymerase chain reaction in the detection of aspergillus fumigatus].to evaluate the performance of locked nucleic acid (lna) probe real-time polymerase chain reaction (pcr) in the detection of aspergillus fumigatus (a. fumigatus).201121756800
experimental evolution of defense against a competitive mold confers reduced sensitivity to fungal toxins but no increased resistance in drosophila larvae.abstract: background: fungal secondary metabolites have been suggested to function as chemical defenses against insect antagonists, i.e. predators and competitors. because insects and fungi often compete for dead organic material, insects may achieve protection against fungi by reducing sensitivity to fungal chemicals. this, in turn, may lead to increased resistance allowing insects better to suppress the spread of antagonistic but non-pathogenic microbes in their habitat. however, it remains co ...201121756302
ehd2 mediates trafficking from the plasma membrane by modulating rac1 activity.ehds, eh domain containing proteins, participate in different stages of endocytosis. ehd2 is a plasma membrane associated, ehd which regulates trafficking from the plasma membrane [1]and recycling [2]. ehd2 has a role in nucleotide dependent membrane remodeling and its atp binding domain is involved in dimerization, which creates a membrane binding region. nucleotide binding is important for association of ehd2 with the plasma membrane, since a nucleotide free mutant (ehd2 t72a) failed to do so ...201121756249
conidial dihydroxynaphthalene melanin of the human pathogenic fungus aspergillus fumigatus interferes with the host endocytosis pathway.aspergillus fumigatus is the most important air-borne fungal pathogen of humans. the interaction of the pathogen with the host's immune system represents a key process to understand pathogenicity. for elimination of invading microorganisms, they need to be efficiently phagocytosed and located in acidified phagolysosomes. however, as shown previously, a. fumigatus is able to manipulate the formation of functional phagolysosomes. here, we demonstrate that in contrast to pigmentless pksp mutant con ...201121747802
proteomics of eukaryotic microorganisms: the medically and biotechnologically important fungal genus aspergillus.fungal species of the genus aspergillus play significant roles as model organisms in basic research, as "cell factories" for the production of organic acids, pharmaceuticals or industrially important enzymes and as pathogens causing superficial and invasive infections in animals and humans. the release of the genome sequences of several aspergillus sp. has paved the way for global analyses of protein expression in aspergilli including the characterisation of proteins, which have not designated a ...201121726053
a unique regulatory mechanism for d-galactose utilization in aspergillus nidulans.this study describes two novel regulators, galx and galr, that control d-galactose utilization in aspergillus nidulans. this system is unique for a. nidulans since no galr homologs were found in other ascomycetes. galr, but not galx, shares significant sequence identity with the arabinanolytic and xylanolytic regulators arar and xlnr, but galx is more distantly related.201121821745
backbone and sidechain (1)h, (13)c and (15)n chemical shift assignments of the hydrophobin dewa from aspergillus nidulans.hydrophobins are proteins secreted by filamentous fungi that are able to self-assemble into monolayers at hydrophobic:hydrophilic interfaces. the layers are amphipathic and can reverse the wettability of surfaces. hydrophobins have several roles in fungal development, including the formation of coatings on fungal structures to render them hydrophobic. here we report the backbone and sidechain assignments for the class i hydrophobin dewa from the fungus aspergillus nidulans.201121845363
two induced fungal polyketide pathways converge into antiproliferative spiroanthrones. 201121698737
redundant ability of phagocytes to kill aspergillus species. 201121689849
bacteria-induced natural product formation in the fungus aspergillus nidulans requires saga/ada-mediated histone acetylation.sequence analyses of fungal genomes have revealed that the potential of fungi to produce secondary metabolites is greatly underestimated. in fact, most gene clusters coding for the biosynthesis of antibiotics, toxins, or pigments are silent under standard laboratory conditions. hence, it is one of the major challenges in microbiology to uncover the mechanisms required for pathway activation. recently, we discovered that intimate physical interaction of the important model fungus aspergillus nidu ...201121825172
roles of the aspergillus nidulans udp-galactofuranose transporter, ugta in hyphal morphogenesis, cell wall architecture, conidiation, and drug sensitivity.galactofuranose (galf) is the 5-member-ring form of galactose found in the walls of fungi including aspergillus, but not in mammals. udp-galactofuranose mutase (ugma, anid_3112.1) generates udp-galf from udp-galactopyranose (6-member ring form). ugma-gfp is cytoplasmic, so the udp-galf residues it produces must be transported into an endomembrane compartment prior to incorporation into cell wall components. anid_3113.1 (which we call ugta) was identified as being likely to encode the a. nidulans ...201121693196
substrate specifity profiling of the aspergillus fumigatus proteolytic secretome reveals consensus motifs with predominance of ile/leu and phe/tyr.the filamentous fungus aspergillus fumigatus (af) can cause devastating infections in immunocompromised individuals. early diagnosis improves patient outcomes but remains challenging because of the limitations of current methods. to augment the clinician's toolkit for rapid diagnosis of af infections, we are investigating af secreted proteases as novel diagnostic targets. the af genome encodes up to 100 secreted proteases, but fewer than 15 of these enzymes have been characterized thus far. give ...201121695046
improved pectinase production in penicillium griseoroseum recombinant strains.aims:ôçé to obtain recombinant strains of penicillium griseoroseum that produce high levels of pectin lyase (pl) and polygalacturonase (pg) simultaneously. methods and results:ôçé a strain with high production of pl was transformed with the plasmid pan52pgg2, containing the gene encoding pg of p.-ágriseoroseum, under control of the gpd promoter gene from aspergillus nidulans. southern blot analysis demonstrated that all strain had at least one copy of pan52pgg2 integrated into the genome. the re ...201121726361
mutational analysis and modeling reveal functionally critical residues in transmembrane segments 1 and 3 of the uapa transporter.earlier, we identified mutations in the first transmembrane segment (tms1) of uapa, a uric acid-xanthine transporter in aspergillus nidulans, that affect its turnover and subcellular localization. here, we use one of these mutations (h86d) and a novel mutation (i74d) as well as genetic suppressors of them, to show that tms1 is a key domain for proper folding, trafficking and turnover. kinetic analysis of mutants further revealed that partial misfolding and deficient trafficking of uapa does not ...201121722649
the mpkb map kinase plays a role in post-karyogamy processes as well as in hyphal anastomosis during sexual development in aspergillus nidulans.two genes encoding map kinase homologs, designated as mpkb and mpkc, were isolated from aspergillus nidulans by pcr with degenerate primers. deletion and over-expression mutants of mpkc showed no detectable phenotypes under any external stress tested. deletion of mpkb caused pleiotropic phenotypes including a failure in forming cleistothecia under any induction conditions for sexual development, increased h++lle cell production, slow hyphal growth and aberrant conidiophore morphology. over-expre ...201121717328
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