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control of reactive oxygen species (ros) production through histidine kinases in aspergillus nidulans under different growth conditions.sensor histidine kinases (hks) are important factors that control cellular growth in response to environmental conditions. the expression of 15 hks from aspergillus nidulans was analyzed by quantitative real-time pcr under vegetative, asexual, and sexual growth conditions. most hks were highly expressed during asexual growth. all hk gene-disrupted strains produced reactive oxygen species (ros). three hks are involved in the control of ros: hysa was the most abundant under the restricted oxygen c ...201424490133
cloning and characterization of a dynein light chain gene from puccinia striiformis f. sp. tritici.stripe rust is one of the most serious wheat diseases worldwide. the fungus puccinia striiformis f. sp. tritici (pst), the causal agent of this disease, is an obligate biotrophic basidiomycete fungus. numerous studies have shown that dyneins play important roles during fungal growth and propagation. however, knowledge is limited regarding the function of dyneins in pst. in this study, we cloned the dynein light chain gene psdlc1 from pst and characterized its expression. the function of psdlc1 w ...201424470306
mitotic regulation of fungal cell-to-cell connectivity through septal pores involves the nima kinase.intercellular bridges are a conserved feature of multicellular organisms. in multicellular fungi, cells are connected directly via intercellular bridges called septal pores. using aspergillus nidulans, we demonstrate for the first time that septal pores are regulated to be opened during interphase but closed during mitosis. septal pore-associated proteins display dynamic cell cycle-regulated locations at mature septa. of importance, the mitotic nima kinase locates to forming septa and surprising ...201424451264
inhibition of nitric oxide and tumour necrosis factor-α production in peritoneal macrophages by aspergillus nidulans melanin.the naturally occurring pigment, melanin is found in organisms of all phylogenetic kingdoms, including fungi, and exhibits a wide range of biological activities. our objective was to investigate the effects of melanin extracted from the fungus aspergillus nidulans on the production of the pro-inflammatory mediators nitric oxide (no) and tumour necrosis factor-α (tnf-α) in peritoneal macrophages and on the viability of mccoy mouse fibroblasts. the results showed that a. nidulans melanin did not s ...201324432378
the transcription factor bcltf1 regulates virulence and light responses in the necrotrophic plant pathogen botrytis cinerea.botrytis cinerea is the causal agent of gray mold diseases in a range of dicotyledonous plant species. the fungus can reproduce asexually by forming macroconidia for dispersal and sclerotia for survival; the latter also participate in sexual reproduction by bearing the apothecia after fertilization by microconidia. light induces the differentiation of conidia and apothecia, while sclerotia are exclusively formed in the absence of light. the relevance of light for virulence of the fungus is not o ...201424415947
inhibition of tau aggregation by three aspergillus nidulans secondary metabolites: 2,ω-dihydroxyemodin, asperthecin, and asperbenzaldehyde.the aggregation of the microtubule-associated protein tau is a significant event in many neurodegenerative diseases including alzheimer's disease. the inhibition or reversal of tau aggregation is therefore a potential therapeutic strategy for these diseases. fungal natural products have proven to be a rich source of useful compounds having wide varieties of biological activity. we have screened aspergillus nidulans secondary metabolites containing aromatic ring structures for their ability to in ...201424414310
a microscopy-based screen employing multiplex genome sequencing identifies cargo-specific requirements for dynein velocity.the timely delivery of membranous organelles and macromolecules to specific locations within the majority of eukaryotic cells depends on microtubule-based transport. here we describe a screening method to identify mutations that have a critical effect on intracellular transport and its regulation using mutagenesis, multicolor-fluorescence microscopy, and multiplex genome sequencing. this screen exploits the filamentous fungus aspergillus nidulans, which has many of the advantages of yeast molecu ...201424403603
assessing the effects of light on differentiation and virulence of the plant pathogen botrytis cinerea: characterization of the white collar complex.organisms are exposed to a tough environment, where acute daily challenges, like light, can strongly affect several aspects of an individual's physiology, including pathogenesis. while several fungal models have been widely employed to understand the physiological and molecular events associated with light perception, various other agricultural-relevant fungi still remain, in terms of their responsiveness to light, in the dark. the fungus botrytis cinerea is an aggressive pathogen able to cause ...201324391918
a putative apses transcription factor is necessary for normal growth and development of aspergillus nidulans.the nsdd gene encoding a gata type transcription factor positively controls sexual development in aspergillus nidulans. according to microarray data, 20 genes that were upregulated by deleting nsdd during various life cycle stages were randomly selected and deleted for functional analysis. none of the mutants showed apparent changes in growth or development compared with those of the wild-type except the an3154 gene that encodes a putative apses transcription factor and is an ortholog of sacchar ...201324385358
functional analysis of the c-ii subgroup killer toxin-like chitinases in the filamentous ascomycete aspergillus nidulans.chitinases are hydrolytic enzymes responsible for chitin polymer degradation. fungal chitinases belong exclusively to glycoside hydrolases family 18 and they are categorized into three phylogenetic groups (a, b and c), which are further divided into subgroups (a-ii to a-v, b-i to b-v and c-i to c-ii). subgroup c chitinases display similarity with the α/β-subunit of the zymocin yeast killer toxin produced by kluyveromyces lactis, suggesting a role of these enzymes in fungal-fungal interactions. i ...201424384382
development of a pyrg mutant of aspergillus oryzae strain s1 as a host for the production of heterologous proteins.the ease with which auxotrophic strains and genes that complement them can be manipulated, as well as the stability of auxotrophic selection systems, are amongst the advantages of using auxotrophic markers to produce heterologous proteins. most auxotrophic markers in aspergillus oryzae originate from chemical or physical mutagenesis that may yield undesirable mutations along with the mutation of interest. an auxotrophic a. oryzae strain s1 was generated by deleting the orotidine-5'-monophosphate ...201324381522
cytoplasmic dynamics of the general nuclear import machinery in apically growing syncytial cells.karyopherins are transporters involved in the bidirectional, selective and active transport of macromolecules through nuclear pores. importin-β1 is the paradigm of karyopherins and, together with its cargo-adapter importin-α, mediates the general nuclear import pathway. here we show the existence of different cellular pools of both importin-α and -β1 homologues, kapa and kapb, in the coenocytic ascomycete aspergillus nidulans. fluorescence analysis of haploid and diploid strains expressing kapb: ...201324376868
figa, a putative homolog of low-affinity calcium system member fig1 in saccharomyces cerevisiae, is involved in growth and asexual and sexual development in aspergillus nidulans.calcium-mediated signaling pathways are widely employed in eukaryotes and are implicated in the regulation of diverse biological processes. in saccharomyces cerevisiae, at least two different calcium uptake systems have been identified: the high-affinity calcium influx system (hacs) and the low-affinity calcium influx system (lacs). compared to the hacs, the lacs in fungi is not well known. in this study, figa, a homolog of the lacs member fig1 from s. cerevisiae, was functionally characterized ...201424376003
down-regulation of sidb gene by use of rna interference in aspergillus nidulans.introduction of the rna interference (rnai) machinery has guided the researchers to discover the function of essential vital or virulence factor genes in the microorganisms such as fungi. in the filamentous fungus aspergillus nidulans, the gene sidb plays an essential role in septation, conidiation and vegetative hyphal growth. in the present study, we benefited from the rnai strategy for down-regulating a vital gene, sidb, in the fungus a. nidulans.201424375164
a novel thermostable xylanase gh10 from malbranchea pulchella expressed in aspergillus nidulans with potential applications in biotechnology.the search for novel thermostable xylanases for industrial use has intensified in recent years, and thermophilic fungi are a promising source of useful enzymes. the present work reports the heterologous expression and biochemical characterization of a novel thermostable xylanase (gh10) from the thermophilic fungus malbranchea pulchella, the influence of glycosylation on its stability, and a potential application in sugarcane bagasse hydrolysis.201425788980
using aspergillus nidulans to identify antifungal drug resistance mutations.systemic fungal infections contribute to at least 10% of deaths in hospital settings. most antifungal drugs target ergosterol (polyenes) or its biosynthetic pathway (azoles and allylamines), or beta-glucan synthesis (echinocandins). antifungal drugs that target proteins are prone to the emergence of resistant strains. identification of genes whose mutations lead to targeted resistance can provide new information on those pathways. we used aspergillus nidulans as a model system to exploit its tra ...201424363365
in vitro photodynamic inactivation of plant-pathogenic fungi colletotrichum acutatum and colletotrichum gloeosporioides with novel phenothiazinium photosensitizers.the increasing tolerance to currently used fungicides in both clinical and agricultural areas is of great concern. the nonconventional light-based approach of antimicrobial photodynamic treatment (apdt) is a promising alternative to conventional fungicides. we evaluated the effects of apdt with four phenothiazinium derivatives (methylene blue [mb], new methylene blue n [nmbn], toluidine blue o [tbo], and the novel pentacyclic phenothiazinium photosensitizer [ps] s137) on conidia of three fungal ...201424362436
a p53-like transcription factor similar to ndt80 controls the response to nutrient stress in the filamentous fungus, aspergillus nidulans.the aspergillus nidulans xprg gene encodes a putative transcriptional activator that is a member of the ndt80 family in the p53-like superfamily of proteins. previous studies have shown that xprg controls the production of extracellular proteases in response to starvation. we undertook transcriptional profiling to investigate whether xprg has a wider role as a global regulator of the carbon nutrient stress response. our microarray data showed that the expression of a large number of genes, inclu ...201324358888
transport assays in filamentous fungi: kinetic characterization of the uapc purine transporter of aspergillus nidulans.transport assays allow the direct kinetic analysis of a specific transporter by measuring apparent km and vmax values, and permit the characterization of substrate specificity profiles through competition assays. in this protocol we describe a rapid and easy method for performing uptake assays in the model filamentous ascomycete aspergillus nidulans. our method makes use of a. nidulans germinating conidiospores at a defined morphological stage in which most transporters show maximal expression, ...201424355588
linkage of oxidative stress and mitochondrial dysfunctions to spontaneous culture degeneration in aspergillus nidulans.filamentous fungi including mushrooms frequently and spontaneously degenerate during subsequent culture maintenance on artificial media, which shows the loss or reduction abilities of asexual sporulation, sexuality, fruiting, and production of secondary metabolites, thus leading to economic losses during mass production. to better understand the underlying mechanisms of fungal degeneration, the model fungus aspergillus nidulans was employed in this study for comprehensive analyses. first, linkag ...201424345786
recent advances in genome mining of secondary metabolite biosynthetic gene clusters and the development of heterologous expression systems in aspergillus nidulans.fungi are prolific producers of secondary metabolites (sms) that show a variety of biological activities. recent advances in genome sequencing have shown that fungal genomes harbor far more sm gene clusters than are expressed under conventional laboratory conditions. activation of these "silent" gene clusters is a major challenge, and many approaches have been taken to attempt to activate them and, thus, unlock the vast treasure chest of fungal sms. this review will cover recent advances in geno ...201424342965
investigating aspergillus nidulans secretome during colonisation of cork cell walls.cork, the outer bark of quercus suber, shows a unique compositional structure, a set of remarkable properties, including high recalcitrance. cork colonisation by ascomycota remains largely overlooked. herein, aspergillus nidulans secretome on cork was analysed (2de). proteomic data were further complemented by microscopic (sem) and spectroscopic (atr-ftir) evaluation of the colonised substrate and by targeted analysis of lignin degradation compounds (uplc-hrms). data showed that the fungus forme ...201424316358
sensitivity of aspergillus nidulans to the cellulose synthase inhibitor dichlobenil: insights from wall-related genes' expression and ultrastructural hyphal morphologies.the fungal cell wall constitutes an important target for the development of antifungal drugs, because of its central role in morphogenesis, development and determination of fungal-specific molecular features. fungal walls are characterized by a network of interconnected glycoproteins and polysaccharides, namely α-, β-glucans and chitin. cell walls promptly and dynamically respond to environmental stimuli by a signaling mechanism, which triggers, among other responses, modulations in wall biosynt ...201324312197
intestinal retransplant in a patient after fungal sepsis: considerations and issues.an adolescent female received an isolated intestinal transplant. she developed severe exfoliative rejection and required complete enterectomy. the patient developed a septic hip and lung lesions with biopsy-proven aspergillus nidulans and was treated with caspofungin, ambiosome, and voriconizole. after completing a year of treatment and extensive physical therapy, the patient requested retransplant. the case was presented to the ethics committee, which determined that the patient demonstrated un ...201324311401
characterization of aspergillus nidulans α-glucan synthesis: roles for two synthases and two amylases.cell walls are essential for fungal survival and growth. fungal walls are ∼ 90% carbohydrate, mostly types not found in humans, making them promising targets for anti-fungal drug development. echinocandins, which inhibit the essential β-glucan synthase, are already clinically available. in contrast, α-glucan, another abundant fungal cell wall component has attracted relatively little research attention because it is not essential for most fungi. aspergillus nidulans has two α-glucan synthases (a ...201424308872
astpt catalyses both reverse n1- and regular c2 prenylation of a methylated bisindolyl benzoquinone.prenylated bisindolyl benzoquinones exhibit interesting biological activities, such as antidiabetic or anti-hiv activities. a number of these compounds, including asterriquinones, have been isolated from aspergillus terreus. in this study, we identified two putative genes by genome mining, ateg_09980 and ateg_00702, which share high sequence similarity with the known bisindolyl benzoquinone prenyltransferase tdib from aspergillus nidulans. the coding sequences were cloned and overexpressed in e. ...201424302698
transcriptome analysis of the filamentous fungus aspergillus nidulans directed to the global identification of promoters.the filamentous fungus aspergillus nidulans has been a tractable model organism for cell biology and genetics for over 60 years. it is among a large number of aspergilli whose genomes have been sequenced since 2005, including medically and industrially important species. in order to advance our knowledge of its biology and increase its utility as a genetic model by improving gene annotation we sequenced the transcriptome of a. nidulans with a focus on 5' end analysis.201324299161
the interplay between the gata transcription factors area, the global nitrogen regulator and areb in fusarium fujikuroi.nitrogen metabolite repression (nmr) in filamentous fungi is controlled by the gata transcription factors area and areb. while area mainly acts as a positive regulator of nmr-sensitive genes, the role of areb is not well understood. we report the characterization of areb and its interplay with area in the gibberellin-producing fungus fusarium fujikuroi. the areb locus produces three different transcripts that each code for functional proteins fully complementing the areb deletion mutant that inf ...201424286256
identification of glucose transporters in aspergillus nidulans.to characterize the mechanisms involved in glucose transport, in the filamentous fungus aspergillus nidulans, we have identified four glucose transporter encoding genes hxtb-e. we evaluated the ability of hxtb-e to functionally complement the saccharomyces cerevisiae eby.vw4000 strain that is unable to grow on glucose, fructose, mannose or galactose as single carbon source. in s. cerevisiae hxtb-e were targeted to the plasma membrane. the expression of hxtb, hxtc and hxte was able to restore gro ...201324282591
interplay of the fungal sumoylation network for control of multicellular development.the role of the complex network of the ubiquitin-like modifier sumo in fungal development was analysed. sumo is not only required for sexual development but also for accurate induction and light stimulation of asexual development. the aspergillus nidulans compass complex including its subunits ccla and the methyltransferase seta connects the sumo network to histone modification. seta is required for correct positioning of aerial hyphae for conidiophore and asexual spore formation. multicellular ...201324279728
secondary metabolites from the fungus emericella nidulans.a new polyketide derivative koninginin h (1), has been isolated from the fungus emericella nidulans, together with koninginin e (2), koninginin a (3), trichodermatide b (4), citrantifidiol (5), (4s,5r)-4-hydroxy-5-methylfuran-2-one (6), the glycerol derivatives gingerglycolipid b (7), (2s)-bis[9z,12z]-1-o, 2-o-dilinoleoyl-3-o-[alpha-d-galactopyranosyl-(1" --> 6') beta-d-galactopyranosyl]glycerol (8), (2s)-bis[9z,12z]-1-o, 2-o-dilinoleoyl-3-o-beta-d-galactopyranosylglycerol (9), the cerebroside f ...201324273867
phosphate solubilizing ability of emericella nidulans strain v1 isolated from vermicompost.phosphorus is one of the key factors that regulate soil fertility. its deficiencies in soil are largely replenished by chemical fertilizers. the present study was aimed to isolate efficient phosphate solubilizing fungal strains from eisenia fetida vermicompost. out of total 30 fungal strains the most efficient phosphate solubilizing one was emericella (aspergillus) nidulans v1 (mtcc 11044), identified by custom sequencing of beta-tubulin gene and blast analysis. this strain solubilized 13 to 36% ...201324266109
ambient ph sensing in filamentous fungi: pitfalls in elucidating regulatory hierarchical signaling networks.in this article, the experiments used to construct the ambient ph-signaling network involved in the secretion of enzymes by filamentous fungi have been reviewed, focusing on the phosphate-repressible phosphatases in aspergillus nidulans. classic and molecular genetics have been used to demonstrate that proteolysis of the transcription factor pacc at alkaline ambient ph is imperative for its action, implying that the full-length version is not an active molecular form of pacc. it has been hypothe ...201324265200
insights into dynamic mitotic chromatin organization through the nima kinase suppressor sonc, a chromatin-associated protein involved in the dna damage response.the nuclear pore complex proteins sona and sonb, the orthologs of mammalian rae1 and nup98, respectively, were identified in aspergillus nidulans as cold-sensitive suppressors of a temperature-sensitive allele of the essential mitotic nima kinase (nima1). subsequent analyses found that sonb1 mutants exhibit temperature-dependent dna damage sensitivity. to understand this pathway further, we performed a genetic screen to isolate additional conditional dna damage-sensitive suppressors of nima1. we ...201424214344
establishing a versatile golden gate cloning system for genetic engineering in fungi.the corn pathogen ustilago maydis is a well-studied fungal model organism. along with a broad set of experimental tools, versatile strategies for the generation of gene replacement mutants by homologous recombination in u. maydis have been developed. nevertheless, the production of corresponding linear dna constructs still constitutes a time-limiting step. to overcome this bottleneck, various resistance cassette modules were adopted for use with the so-called golden gate cloning strategy. these ...201424211735
the aspergillus nidulans atm kinase regulates mitochondrial function, glucose uptake and the carbon starvation response.mitochondria supply cellular energy and also perform a role in the adaptation to metabolic stress. in mammals, the ataxia-telangiectasia mutated (atm) kinase acts as a redox sensor controlling mitochondrial function. subsequently, transcriptomic and genetic studies were utilized to elucidate the role played by a fungal atm homolog during carbon starvation. in aspergillus nidulans, atma was shown to control mitochondrial function and glucose uptake. carbon starvation responses that are regulated ...201424192833
the nima kinase is required to execute stage-specific mitotic functions after initiation of mitosis.the g2-m transition in aspergillus nidulans requires the nima kinase, the founding member of the nek kinase family. inactivation of nima results in a late g2 arrest, while overexpression of nima is sufficient to promote mitotic events independently of cell cycle phase. endogenously tagged nima-gfp has dynamic mitotic localizations appearing first at the spindle pole body and then at nuclear pore complexes before transitioning to within nuclei and the mitotic spindle and back at the spindle pole ...201424186954
weta is required for conidiogenesis and conidium maturation in the ascomycete fungus fusarium graminearum.fusarium graminearum, a prominent fungal pathogen that infects major cereal crops, primarily utilizes asexual spores to spread disease. to understand the molecular mechanisms underlying conidiogenesis in f. graminearum, we functionally characterized the f. graminearum ortholog of aspergillus nidulans weta, which has been shown to be involved in conidiogenesis and conidium maturation. deletion of f. graminearum weta did not alter mycelial growth, sexual development, or virulence, but the weta del ...201424186953
the cop9 signalosome is involved in the regulation of lipid metabolism and of transition metals uptake in saccharomyces cerevisiae.the cop9 signalosome (csn) is a highly conserved eukaryotic protein complex which regulates the cullin ring family of ubiquitin ligases and carries out a deneddylase activity that resides in subunit 5 (csn5). whereas csn activity is essential for the development of higher eukaryotes, several unicellular fungi including the budding yeast saccharomyces cerevisiae can survive without a functional csn. nevertheless, the budding yeast csn is biochemically active and deletion mutants of each of its su ...201424164706
the n-terminus region of the putative c2h2 transcription factor ada1 harbors a species-specific activation motif that regulates asexual reproduction in fusarium verticillioides.fusarium verticillioides is an important plant pathogenic fungus causing maize ear and stalk rots. in addition, the fungus is directly associated with fumonisin contamination of food and feeds. here, we report the functional characterization of ada1, a putative cys2-his2 zinc finger transcription factor with a high level of similarity to aspergillus nidulans flbc, which is required for the activation of the key regulator of conidiation brla. ada1 is predicted to encode a protein with two dna bin ...201424161731
the mpkb map kinase plays a role in autolysis and conidiation of aspergillus nidulans.the mpkb gene of aspergillus nidulans encodes a map kinase homologous to fus3p of saccharomyces cerevisiae which is involved in conjugation process. mpkb is required for completing the sexual development at the anastomosis and post-karyogamy stages. the mpkb deletion strain could produce conidia under the repression condition of conidiation such as sealing and even in the submerged culture concomitant with persistent brla expression, implying that mpkb might have a role in timely regulation of b ...201324161728
fatty acids with in vitro binding affinity for human opioid receptors from the fungus emericella nidulans.bioassay-guided fractionation of the etoac extracts of the epiphytic fungus emericella nidulans resulted in the isolation of a mixture of two fatty acids. this mixture showed 98% binding affinity to human δ opioid receptor. these two fatty acids were identified as palmitic (pam), 1, and linoleic acids (lna), 2, by 1d nmr as well as by gc/ms analysis, after their methylation. we found that different ratio mixtures of 1 and 2 showed variations in selective binding activities to human δ opioid rece ...201324147790
cost-effective isobaric tagging for quantitative phosphoproteomics using diart reagents.we describe the use of an isobaric tagging reagent, deuterium isobaric amine reactive tag (diart), for quantitative phosphoproteomic experiments. using diart tagged custom mixtures of two phosphorylated peptides from alpha casein and their non-phosphorylated counterparts, we demonstrate the compatibility of diart with tio2 affinity purification of phosphorylated peptides. comparison of theoretical vs. experimental reporter ion ratios reveals accurate quantification of phosphorylated peptides ove ...201324129742
in vitro and in silico analysis of the aspergillus nidulans dna-crea repressor interactions.the crea protein mediates carbon catabolite repression in the fungus aspergillus nidulans. its dna-binding domain belongs to the cys2-his2 class, binding specifically to a 5' syggrg 3' nucleotide sequence. emsa experiments showed that the crea(g27d) mutation resulted in a 30-fold increase of the kdiss, and footprinting revealed a altered pattern of protein/dna contacts. we modeled the crea and the crea(g27d) complexes in silico. a 15 ns molecular dynamics simulation of the solvated crea(g27d) an ...201424125468
proteomic alterations induced by ionic liquids in aspergillus nidulans and neurospora crassa.this study constitutes the first attempt to understand at the proteomic level the fungal response to ionic liquid stress. ascomycota are able to grow in media supplemented with high concentrations of an ionic liquid, which, in turn, lead to major alterations in the fungal metabolic footprint. herein, we analysed the differential accumulation of mycelial proteins in aspergillus nidulans and neurospora crassa after their exposure to two of the most commonly used ionic liquids: 1-ethyl-3-methylimid ...201324120530
involvement of the anucleate primary sterigmata protein fgapsb in vegetative differentiation, asexual development, nuclear migration, and virulence in fusarium graminearum.the protein apsb has been shown to play critical roles in the migration and positioning of nuclei and in the development of conidiophores in aspergillus nidulans. the functions of apsb in fusarium graminearum, a causal agent of fusarium head blight in china, are largely unknown. in this study, we used the blastp program at the broad institute to identify fgapsb, an f. graminearum homolog of a. nidulansapsb. the functions of fgapsb were evaluated by constructing a deletion mutant of fgapsb, desig ...201324117691
elucidation of substrate specificity in aspergillus nidulans udp-galactose-4-epimerase.the frequency of invasive fungal infections has rapidly increased in recent years. current clinical treatments are experiencing decreased potency due to severe host toxicity and the emergence of fungal drug resistance. as such, new targets and their corresponding synthetic pathways need to be explored for drug development purposes. in this context, galactofuranose residues, which are employed in fungal cell wall construction, but are notably absent in animals, represent an appealing target. here ...201324116166
penicillium decumbens brla extensively regulates secondary metabolism and functionally associates with the expression of cellulase genes.penicillium decumbens has been used in the industrial production of lignocellulolytic enzymes in china for more than 15 years. conidiation is essential for most industrial fungi because conidia are used as starters in the first step of fermentation. to investigate the mechanism of conidiation in p. decumbens, we generated mutants defective in two central regulators of conidiation, flug and brla. deletion of flug resulted in neither "fluffy" phenotype nor alteration in conidiation, indicating pos ...201324113825
the cell-end marker teaa and the microtubule polymerase alpa contribute to microtubule guidance at the hyphal tip cortex of aspergillus nidulans to provide polarity maintenance.in the absence of landmark proteins, hyphae of aspergillus nidulans lose their direction of growth and show a zigzag growth pattern. here, we show that the cell-end marker protein teaa is important for localizing the growth machinery at hyphal tips. the central position of teaa at the tip correlated with the convergence of the microtubule (mt) ends to a single point. conversely, in the absence of teaa, the mts often failed to converge to a single point at the cortex. further analysis suggested a ...201324101725
4-phenyl-3,4-dihydroquinolone derivatives from aspergillus nidulans ma-143, an endophytic fungus isolated from the mangrove plant rhizophora stylosa.six new 4-phenyl-3,4-dihydroquinolone derivatives (1-6) along with the related aflaquinolone a (7) were isolated and identified from the cultures of aspergillus nidulans ma-143, an endophytic fungus obtained from the fresh leaves of the marine mangrove plant rhizophora stylosa. their structures including absolute configurations were determined by spectroscopic analysis and electronic circular dichroism experiments, and the structure of compound 1 was confirmed by single-crystal x-ray crystallogr ...201324099304
bzip transcription factor smjlb1 regulates autophagy-related genes smatg8 and smatg4 and is required for fruiting-body development and vegetative growth in sordaria macrospora.autophagy is a precisely controlled degradation process in eukaryotic cells, during which the bulk of the cytoplasm is engulfed by a double membrane vesicle, the autophagosome. fusion of the autophagosome with the vacuole leads to breakdown of its contents, such as proteins and organelles, and the recycling of nutrients. earlier studies of autophagic genes of the core autophagic machinery in the filamentous ascomycete sordaria macrospora elucidated the impact of autophagy on fungal viability, ve ...201324095659
novel and cost-effective 6-plex isobaric tagging reagent, diart, is effective for identification and relative quantification of complex protein mixtures using pqd fragmentation.deuterium isobaric amine reactive tag (diart) reagents facilitate relative quantification during proteomic analysis in a functionally similar manner to commercially available isobaric tag for relative and absolute quantitation (itraq) and tandem mass tag (tmt) reagents. in contrast to itraq and tmt, diart reagents incorporate deuterium isotopes which significantly reduce the number of required synthesis steps and hence have potential to significantly reduce reagent production cost. we examined t ...201324078244
fungal metabolic plasticity and sexual development mediate induced resistance to arthropod fungivory.prey organisms do not tolerate predator attack passively but react with a multitude of inducible defensive strategies. although inducible defence strategies are well known in plants attacked by herbivorous insects, induced resistance of fungi against fungivorous animals is largely unknown. resistance to fungivory is thought to be mediated by chemical properties of fungal tissue, i.e. by production of toxic secondary metabolites. however, whether fungi change their secondary metabolite compositio ...201324068353
the putative c2h2 transcription factor mtfa is a novel regulator of secondary metabolism and morphogenesis in aspergillus nidulans.secondary metabolism in the model fungus aspergillus nidulans is controlled by the conserved global regulator vea, which also governs morphological differentiation. among the secondary metabolites regulated by vea is the mycotoxin sterigmatocystin (st). the presence of vea is necessary for the biosynthesis of this carcinogenic compound. we identified a revertant mutant able to synthesize st intermediates in the absence of vea. the point mutation occurred at the coding region of a gene encoding a ...201324066102
in situ analysis of apoptosis in aspergillus nidulans with ethidium bromide and acridine orange.apoptosis and necrosis are among several types of cell death. we stained the nuclei of aspergillus nidulans grown in micro-colonies with ethidium bromide and acridine orange to detect in situ apoptosis. suspensions of conidia from 5-day-old colonies of the a. nidulans strains bia1methg1, g422, clc100, and clb3 were each put into two tubes. the suspension of one tube was irradiated with ultraviolet light for 20 s, whereas the other tube was not exposed to irradiation. the two suspensions were ino ...201324065645
abaa regulates conidiogenesis in the ascomycete fungus fusarium graminearum.fusarium graminearum (teleomorph gibberella zeae) is a prominent pathogen that infects major cereal crops such as wheat, barley, and maize. both sexual (ascospores) and asexual (conidia) spores are produced in f. graminearum. since conidia are responsible for secondary infection in disease development, our objective of the present study was to reveal the molecular mechanisms underlying conidiogenesis in f. graminearum based on the framework previously described in aspergillus nidulans. in this s ...201324039821
recombinant aspergillus β-galactosidases as a robust glycomic and biotechnological tool.galactosidases are widespread enzymes that are used for manifold applications, including production of prebiotics, biosynthesis of different transgalactosylated products, improving lactose tolerance and in various analytical approaches. the nature of these applications often require galactosidases to be present in a purified form with clearly defined properties, including precisely determined substrate specificities, low sensitivity to inhibitors, and high efficiency and stability under distinct ...201424037406
regulation of the nadp-glutamate dehydrogenase gene gdha in aspergillus nidulans by the zn(ii)2cys6 transcription factor leub.nadp-dependent glutamate dehydrogenase (nadp-gdh) is a key enzyme in the assimilation of alternative nitrogen nutrient sources through ammonium in fungi. in aspergillus nidulans, nadp-gdh is encoded by gdha. several transcription factors are known to regulate gdha expression, including area, the major transcription activator of nitrogen metabolic genes, and tama, a co-activator of area. tama also interacts with leub, the regulator of leucine biosynthesis. we have investigated the effects of leuc ...201324025604
induced fungal resistance to insect grazing: reciprocal fitness consequences and fungal gene expression in the drosophila-aspergillus model system.fungi are key dietary resources for many animals. fungi, in consequence, have evolved sophisticated physical and chemical defences for repelling and impairing fungivores. expression of such defences may entail costs, requiring diversion of energy and nutrients away from fungal growth and reproduction. inducible resistance that is mounted after attack by fungivores may allow fungi to circumvent the potential costs of defence when not needed. however, no information exists on whether fungi display ...201324023705
phylogenetic analysis and substrate specificity of gh2 β-mannosidases from aspergillus species.phylogenetic analysis of glycoside hydrolase family 2 including aspergillus sequences and characterised β-mannosidases from other organisms, clusters putative aspergillus β-mannosidases in two distinct clades (a and b). aspergillus species have at least one paralog in each of the two clades. it appears that clade a members are extracellular and clade b members intracellular. substrate specificity analysis of mnda of aspergillus niger (clade a) and mndb of aspergillus nidulans (clade b) show that ...201324021641
nudix hydrolase controls nucleotides and glycolytic mechanisms in hypoxic aspergillus nidulans.nucleoside diphosphates linked to moiety x (nudix) hydrolase functions were investigated in hypoxic aspergillus nidulans cells. among three nudix hydrolase isozymes, ndxa transcription was up-regulated under oxygen (o2)-limited conditions. a gene disruptant of the ndxa-encoding gene (ndxaδ) accumulated more nadh and adp-ribose than the wild type (wt) under the same conditions. these results indicate that ndxa hydrolyzes these nucleotides in hypoxic fungal cells, which accords with the thesis tha ...201324018665
inhibition of cereal rust fungi by both class i and ii defensins derived from the flowers of nicotiana alata.defensins are a large family of small, cysteine-rich, basic proteins, produced by most plants and plant tissues. they have a primary function in defence against fungal disease, although other functions have been described. this study reports the isolation and characterization of a class i secreted defensin (nad2) from the flowers of nicotiana alata, and compares its antifungal activity with the class ii defensin (nad1) from n. alata flowers, which is stored in the vacuole. nad2, like all other c ...201424015961
engineered fungal polyketide biosynthesis in pichia pastoris: a potential excellent host for polyketide production.polyketides are one of the most important classes of secondary metabolites and usually make good drugs. currently, heterologous production of fungal polyketides for developing a high potential industrial application system with high production capacity and pharmaceutical feasibility was still at its infancy. pichia pastoris is a highly successful system for the high production of a variety of heterologous proteins. in this work, we aim to develop a p. pastoris based in vivo fungal polyketide pro ...201324011431
heterologous reconstitution of the intact geodin gene cluster in aspergillus nidulans through a simple and versatile pcr based approach.fungal natural products are a rich resource for bioactive molecules. to fully exploit this potential it is necessary to link genes to metabolites. genetic information for numerous putative biosynthetic pathways has become available in recent years through genome sequencing. however, the lack of solid methodology for genetic manipulation of most species severely hampers pathway characterization. here we present a simple pcr based approach for heterologous reconstitution of intact gene clusters. s ...201324009710
characterization and identification of partial amino acid sequence of a novel elastase inhibitor, asnidin from aspergillus nidulans.a novel elastase inhibitor from aspergillus nidulans nbrc 4340, asnidin, was isolated, and biochemical properties and partial amino acid sequence were examined. column chromatography using diethylaminoethyl (de) 52-cellulose and reversed-phase hplc were used to purify the inhibitor. purified asnidin was found to be homogeneous as indicated by reversed-phase hplc and tof-ms (time of flight mass spectrometry). asnidin has a molecular weight of 4,181.63 as determined by tof-ms. the elastolytic acti ...201323995417
aspergillus nidulans synthesize insect juvenile hormones upon expression of a heterologous regulatory protein and in response to grazing by drosophila melanogaster larvae.secondary metabolites are known to serve a wide range of specialized functions including communication, developmental control and defense. genome sequencing of several fungal model species revealed that the majority of predicted secondary metabolite related genes are silent in laboratory strains, indicating that fungal secondary metabolites remain an underexplored resource of bioactive molecules. in this study, we combine heterologous expression of regulatory proteins in aspergillus nidulans wit ...201323991191
in praise of erroneous hypotheses.in the sixties cove and pateman discovered that mutants of aspergillus nidulans lacking nitrate reductase activity were constitutive for the expression of genes induced by nitrate and dependent on the transcription factor nira. they proposed that the nitrate protein acted as a repressor, preventing the transcription factor activity of nira. nitrate-mediated regulation behaved similarly in other organisms. this "autogenous regulation hypothesis" has recently shown to be erroneous, in the very org ...201323973960
no-inducible nitrosothionein mediates no removal in tandem with thioredoxin.nitric oxide (no) is a toxic reactive nitrogen species that induces microbial adaption mechanisms. screening a genomic dna library identified a new gene, ntpa, that conferred growth tolerance upon aspergillus nidulans against exogenous no. the gene encoded a cysteine-rich 23-amino-acid peptide that reacted with no and s-nitrosoglutathione to generate an s-nitrosated peptide. disrupting ntpa increased amounts of cellular s-nitrosothiol and no susceptibility. thioredoxin and its reductase denitros ...201323955366
spread and change in stress resistance of shiga toxin-producing escherichia coli o157 on fungal colonies.to elucidate the effect of fungal hyphae on the behaviour of shiga toxin-producing escherichia coli (stec) o157, the spread and change in stress resistance of the bacterium were evaluated after coculture with 11 species of food-related fungi including fermentation starters. spread distances of stec o157 varied depending on the co-cultured fungal species, and the motile bacterial strain spread for longer distances than the non-motile strain. the population of stec o157 increased when co-cultured ...201423919289
characterizations and functions of regulator of g protein signaling (rgs) in fungi.proteins that serve as regulator of g protein signaling (rgs) primarily function as gtpase accelerators that promote gtp hydrolysis by the gα subunits, thereby inactivating the g protein and rapidly switching off g protein-coupled signaling pathways. since the first rgs protein was identified from the budding yeast saccharomyces cerevisiae, more than 30 rgs and rgs-like proteins have been characterized from several model fungi, such as aspergillus nidulans, beauveria bassiana, candida albicans, ...201323917634
the binding of zinc ions to emericella nidulans endo-β-1,4-galactanase is essential for crystal formation.a novel emericella nidulans endo-β-1,4-galactanase (engal) demonstrates a strong capacity to generate high levels of very potent prebiotic oligosaccharides from potato pulp, a by-product of the agricultural potato-starch industry. engal belongs to glycoside hydrolase family 53 and shows high (72.5%) sequence identity to an endo-β-1,4-galactanase from aspergillus aculeatus. diffraction data extending to 2.0 å resolution were collected from a crystal of engal grown from conditions containing 0.2 m ...201323908026
a novel thermophilic endo-β-1,4-mannanase from aspergillus nidulans xz3: functional roles of carbohydrate-binding module and thr/ser-rich linker region.the gene man5xz3 from aspergillus nidulans xz3 encodes a multimodular β-mannanase of glycoside hydrolase family 5 that consists of a family 1 carbohydrate-binding module (cbm1), a thr/ser-rich linker region, and a catalytic domain. recombinant man5xz3 and its two truncated derivatives, man5δcbm (removing the cbm1) and man5δcl (removing both the cbm1 and linker region), were produced in pichia pastoris and showed significant variance in the secondary structure. the three enzymes had similar bioch ...201423900799
distinct amino acids of histone h3 control secondary metabolism in aspergillus nidulans.chromatin remodelling events play an important role in the secondary metabolism of filamentous fungi. previously, we showed that a bacterium, streptomyces rapamycinicus, is able to reprogram the histone-modifying spt-ada-gcn5-acetyltransferase/ada (saga/ada) complex of the model fungus aspergillus nidulans. consequently, the histone h3 amino acids lysine 9 and lysine 14 at distinct secondary metabolism genes were specifically acetylated during the bacterial fungal interaction, which, furthermore ...201323892751
aniquinazolines a-d, four new quinazolinone alkaloids from marine-derived endophytic fungus aspergillus nidulans.four new quinazolinone alkaloids, namely, aniquinazolines a-d (1-4), were isolated and identified from the culture of aspergillus nidulans ma-143, an endophytic fungus obtained from the leaves of marine mangrove plant rhizophora stylosa. the structures of the new compounds were elucidated by spectroscopic analysis, and their absolute configurations were determined on the basis of chiral hplc analysis of the acidic hydrolysates. the structure for 1 was confirmed by single-crystal x-ray diffractio ...201323880937
functional roles of fglaea in controlling secondary metabolism, sexual development, and virulence in fusarium graminearum.fusarium graminearum, the causal agent of fusarium head blight in cereal crops, produces mycotoxins such as trichothecenes and zearalenone in infected plants. here, we focused on the function of fglaea in f. graminearum, a homolog of aspergillus nidulans laea encoding the global regulator for both secondary metabolism and sexual development. prior to gene analysis, we constructed a novel luciferase reporter system consisting of a transgenic f. graminearum strain expressing a firefly luciferase g ...201323874628
reproductive competence: a recurrent logic module in eukaryotic development.developmental competence is the ability to differentiate in response to an appropriate stimulus, as first elaborated by waddington in relation to organs and tissues. competence thresholds operate at all levels of biological systems from the molecular (e.g. the cell cycle) to the ontological (e.g. metamorphosis and reproduction). reproductive competence, an organismal process, is well studied in mammals (sexual maturity) and plants (vegetative phase change), though far less than later stages of t ...201323864594
new interfacial microtubule inhibitors of marine origin, pm050489/pm060184, with potent antitumor activity and a distinct mechanism.we have investigated the target and mechanism of action of a new family of cytotoxic small molecules of marine origin. pm050489 and its dechlorinated analogue pm060184 inhibit the growth of relevant cancer cell lines at subnanomolar concentrations. we found that they are highly potent microtubule inhibitors that impair mitosis with a distinct molecular mechanism. they bind with nanomolar affinity to unassembled αβ-tubulin dimers, and pm050489 binding is inhibited by known vinca domain ligands. n ...201323859655
deleterious effects of recombination and possible nonrecombinatorial advantages of sex in a fungal model.why sexual reproduction is so prevalent in nature remains a major question in evolutionary biology. most of the proposed advantages of sex rely on the benefits obtained from recombination. however, it is still unclear whether the conditions under which these recombinatorial benefits would be sufficient to maintain sex in the short term are met in nature. our study addresses a largely overlooked hypothesis, proposing that sex could be maintained in the short term by advantages due to functions li ...201323848947
vea and mvla repression of the cryptic orsellinic acid gene cluster in aspergillus nidulans involves histone 3 acetylation.a perplexing aspect of fungal secondary metabolite gene clusters is that most clusters remain 'silent' under common laboratory growth conditions where activation is obtained through gene manipulation or encounters with environmental signals. few proteins have been found involved in repression of silent clusters. through multicopy suppressor mutagenesis, we have identified a novel cluster suppressor in aspergillus nidulans, mvla (modulator of vea loss). genetic assessment of mvla mutants revealed ...201323841751
rrma regulates the stability of specific transcripts in response to both nitrogen source and oxidative stress.differential regulation of transcript stability is an effective means by which an organism can modulate gene expression. a well-characterized example is glutamine signalled degradation of specific transcripts in aspergillus nidulans. in the case of area, which encodes a wide-domain transcription factor mediating nitrogen metabolite repression, the signal is mediated through a highly conserved region of the 3' utr. utilizing this rna sequence we isolated rrma, an rna recognition motif protein. di ...201323841692
role of the zinc finger transcription factor slta in morphogenesis and sterigmatocystin biosynthesis in the fungus aspergillus nidulans.potassium, a widely accepted macronutrient, is vital for many physiological processes such as regulation of cell volume, maintenance of intracellular ph, synthesis of proteins and activation of enzymes in filamentous fungi. another cation, calcium, plays an essential role in many signaling processes from lower to higher eukaryotes. imbalance in the intracellular ionic levels of potassium or calcium causes adverse effects on cell growth, morphology and development, and eventually death. previous ...201323840895
deletion of creb in aspergillus oryzae increases secreted hydrolytic enzyme activity.aspergillus oryzae has been used in the food and beverage industry for centuries, and industrial strains have been produced by multiple rounds of selection. targeted gene deletion technology is particularly useful for strain improvement in such strains, particularly when they do not have a well-characterized meiotic cycle. phenotypes of an aspergillus nidulans strain null for the creb deubiquitinating enzyme include effects on growth and repression, including increased activity levels of various ...201323835170
the aspergillus nidulans peripheral er: disorganization by er stress and persistence during mitosis.the genetically amenable fungus aspergillus nidulans is well suited for cell biology studies involving the secretory pathway and its relationship with hyphal tip growth by apical extension. we exploited live-cell epifluorescence microscopy of the er labeled with the translocon component sec63, endogenously tagged with gfp, to study the organization of 'secretory' er domains. the sec63 a. nidulans er network includes brightly fluorescent peripheral strands and more faintly labeled nuclear envelop ...201323826221
xylh encodes a xylose/h+ symporter from the highly related yeast species debaryomyces fabryi and debaryomyces hansenii.the closely related yeasts debaryomyces fabryi and debaryomyces hansenii are excellent xylose consumers. we previously described the activity of a high-affinity xylose/h(+) symport from an industrial strain of d. hansenii subsequently reclassified as d. fabryi. we now report the identification of the gene encoding this permease, ay347871.2. this was retrieved from d. fabryi gdna using a degenerate primer pcr strategy, based on conserved regions from the amino acid sequences of three well-charact ...201323809840
functional characterisation of the non-essential protein kinases and phosphatases regulating aspergillus nidulans hydrolytic enzyme production.despite recent advances in the understanding of lignocellulolytic enzyme regulation, less is known about how different carbon sources are sensed and the signaling cascades that result in the adaptation of cellular metabolism and hydrolase secretion. therefore, the role played by non-essential protein kinases (npk) and phosphatases (npp) in the sensing of carbon and/or energetic status was investigated in the model filamentous fungus aspergillus nidulans.201323800192
a structural model of ppoa derived from saxs-analysis-implications for substrate conversion.in plants and mammals, oxylipins may be synthesized via multi step processes that consist of dioxygenation and isomerization of the intermediately formed hydroperoxy fatty acid. these processes are typically catalyzed by two distinct enzyme classes: dioxygenases and cytochrome p450 enzymes. in ascomycetes biosynthesis of oxylipins may proceed by a similar two-step pathway. an important difference, however, is that both enzymatic activities may be combined in a single bifunctional enzyme. these t ...201323797010
allopurinol and xanthine use different translocation mechanisms and trajectories in the fungal uapa transporter.in aspergillus nidulans uapa is a h(+)-driven transporter specific for xanthine, uric acid and several analogues. here, genetic and physiological evidence is provided showing that allopurinol is a high-affinity, low-capacity, substrate for uapa. surprisingly however, transport kinetic measurements showed that, uniquely among all recognized uapa substrates, allopurinol is transported by apparent facilitated diffusion and exhibits a paradoxical effect on the transport of physiological substrates. ...201323791789
metformin's performance in in vitro and in vivo genetic toxicology studies.metformin is a hypoglycemiant drug prescribed for the treatment and control of the type 2 diabetes mellitus. recently, the potential efficacy of this antidiabetic drug as an anticancer agent has been demonstrated in various mammalian cancer cells. this report evaluates the mutagenic as well as the recombinogenic potentials of the metformin drug in therapeutically relevant plasma concentrations (12.5 µm, 25.0 µm or 50.0 µm). since the loss of heterozygosity is a process associated with carcinogen ...201323788173
immobilization and biochemical properties of the enantioselective recombinant nstci esterase of aspergillus nidulans.the recombinant nstci a. nidulans esterase was adsorbed on accurel mp1000, where protein yield and immobilization efficiency were 42.48% and 81.94%, respectively. storage stability test at 4°c and rt showed 100% of residual activity after 40 days at both temperatures. the biocatalyst retains more than 70% of its initial activity after 3 cycles of repeated use. biochemical properties of this new biocatalyst were obtained. maximum activity was achieved at ph 11 and 30°c, while the best stability w ...201323781330
phospho-regulation and nucleocytoplasmic trafficking of crza in response to calcium and alkaline-ph stress in aspergillus nidulans.tolerance to abiotic stresses by microorganisms require of appropriate signalling and regulatory pathways. calcineurin phosphatases mediate calcium-dependent signalling pathways which are widely distributed among phylogeny. in saccharomyces cerevisiae, calcineurin mediates the post-translational modification of downstream effectors, most of them transcription factors, being the best-characterized calcineurin-regulated zinc-finger factor 1, crz1p. here we study the signalling process of crza, a f ...201323772954
analysis of a conserved cellulase transcriptional regulator reveals inducer-independent production of cellulolytic enzymes in neurospora crassa.cellulose is recalcitrant to deconstruction to glucose for use in fermentation strategies for biofuels and chemicals derived from lignocellulose. in neurospora crassa, the transcriptional regulator, clr-2, is required for cellulolytic gene expression and cellulose deconstruction. to assess conservation and divergence of cellulase gene regulation between fungi from different ecological niches, we compared clr-2 function with its ortholog (clrb) in the distantly related species, aspergillus nidula ...201323766336
the spt-ada-gcn5 acetyltransferase (saga) complex in aspergillus nidulans.a mutation screen in aspergillus nidulans uncovered mutations in the acdx gene that led to altered repression by acetate, but not by glucose. acdx of a. nidulans is highly conserved with spt8p of saccharomyces cerevisiae, and since spt8p is a component of the spt-ada-gcn5 acetyltransferase (saga) complex, the saga complex may have a role in acetate repression in a. nidulans. we used a bioinformatic approach to identify genes encoding most members of the saga complex in a. nidulans, and a proteom ...201323762321
co-immobilization of fungal endo-xylanase and α-l-arabinofuranosidase in glyoxyl agarose for improved hydrolysis of arabinoxylan.plant cell-wall arabinoxylans have a complex structure that requires the action of a pool of debranching (arabinofuranosidases) and depolymerizing enzymes (endo-xylanase). two aspergillus nidulans strains over-secreting endo-xylanase and arabinofuranosidase were inoculated in defined 2% maltose-minimum medium resulting in the simultaneously production of these enzymes. to study the synergistic hydrolysis was used arabinoxylan with 41% of arabinose and 59% of xylose residues. thus, it was adopted ...201323756760
uridylation prevents 3' trimming of oligoadenylated mrnas.degradation of mrnas is usually initiated by deadenylation, the shortening of long poly(a) tails to oligo(a) tails of 12-15 as. deadenylation leads to decapping and to subsequent 5' to 3' degradation by xrn proteins, or alternatively 3' to 5' degradation by the exosome. decapping can also be induced by uridylation as shown for the non-polyadenylated histone mrnas in humans and for several mrnas in schizosaccharomyces pombe and aspergillus nidulans. here we report a novel role for uridylation in ...201323748567
highly glucose tolerant β-glucosidase from aspergillus unguis: nii 08123 for enhanced hydrolysis of biomass.aspergillus unguis nii-08123, a filamentous fungus isolated from soil, was found to produce β-glucosidase (bgl) activity with high glucose tolerance. cultivation of the fungus in different carbon sources resulted in the secretion of different isoforms of the enzyme. a low molecular weight isoform, which retained ~60 % activity in the presence of 1.5 m glucose, was purified to homogeneity and the purified enzyme exhibited a temperature and ph optima of 60 °c and 6, respectively. the k(m) and v(ma ...201323732694
strain improvement by overexpression of the laea gene in monascus pilosus for the production of monascus-fermented rice.monascus species have been used to produce fermented rice called monascus-fermented rice (mfr). to improve a monascus strain via activation of secondary metabolite (sm) gene clusters for use in the production of mfr, we overexpressed an ortholog of the laea gene, which encodes a global positive regulator of secondary metabolism under the control of the strong heterologous aspergillus nidulans alca promoter in monascus pilosus. the oe::laea transformant produced more sms, including those not dete ...201323727802
live-cell imaging of aspergillus nidulans autophagy: rab1 dependence, golgi independence and er involvement.we exploited the amenability of the fungus aspergillus nidulans to genetics and live-cell microscopy to investigate autophagy. upon nitrogen starvation, gfp-atg8-containing pre-autophagosomal puncta give rise to cup-shaped phagophores and circular (0.9-μm diameter) autophagosomes that disappear in the vicinity of the vacuoles after their shape becomes irregular and their gfp-atg8 fluorescence decays. this 'autophagosome cycle' gives rise to characteristic cone-shaped traces in kymographs. autoph ...201323722157
acute inactivation of the aspergillus nidulans golgi membrane fusion machinery: correlation of apical extension arrest and tip swelling with cisternal disorganization.the mechanisms governing traffic across the golgi are incompletely understood. we studied, by live-cell microscopy, the consequences of disorganizing the aspergillus nidulans golgi, using an extended set of fluorescent protein markers to resolve early from late cisternae. the early golgi syntaxin sedv(sed) (5) and the rabo(rab) (1) regulatory gtpase play essential roles in secretion, cooperating in the er-golgi interface. following a temperature shift-up 'on-the-stage', hyphae carrying engineere ...201323714354
molecular genetic characterization of the biosynthesis cluster of a prenylated isoindolinone alkaloid aspernidine a in aspergillus nidulans.aspernidine a is a prenylated isoindolinone alkaloid isolated from the model fungus aspergillus nidulans. a genome-wide kinase knockout library of a. nidulans was examined, and it was found that a mitogen-activated protein kinase gene, mpka, deletion strain produces aspernidine a. targeted gene deletions were performed in the kinase deletion background to identify the gene cluster for aspernidine a biosynthesis. intermediates were isolated from mutant strains which provided information about the ...201323706169
neurospora crassa nkin2, a kinesin-3 motor, transports early endosomes and is required for polarized growth.biological motors are molecular nanomachines, which convert chemical energy into mechanical forces. the combination of mechanoenzymes with structural components, such as the cytoskeleton, enables eukaryotic cells to overcome entropy, generate molecular gradients, and establish polarity. hyphae of filamentous fungi are among the most polarized cells, and polarity defects are most obvious. here, we studied the role of the kinesin-3 motor, nkin2, in neurospora crassa. we found that nkin2 localizes ...201323687116
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