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fungal siderophore biosynthesis is partially localized in peroxisomes.siderophores play a central role in iron metabolism and virulence of most fungi. both aspergillus fumigatus and aspergillus nidulans excrete the siderophore triacetylfusarinine c (tafc) for iron acquisition. in a. fumigatus, green fluorescence protein-tagging revealed peroxisomal localization of the tafc biosynthetic enzymes sidi (mevalonyl-coa ligase), sidh (mevalonyl-coa hydratase) and sidf (anhydromevalonyl-coa transferase), while elimination of the peroxisomal targeting signal (pts) impaired ...201323617799
an efficient system for heterologous expression of secondary metabolite genes in aspergillus nidulans.fungal secondary metabolites (sms) are an important source of medically valuable compounds. genome projects have revealed that fungi have many sm biosynthetic gene clusters that are not normally expressed. to access these potentially valuable, cryptic clusters, we have developed a heterologous expression system in aspergillus nidulans . we have developed an efficient system for amplifying genes from a target fungus, placing them under control of a regulatable promoter, transferring them into a. ...201323621425
light sensing in aspergillus fumigatus highlights the case for establishing new models for fungal photobiology.microbes inhabit diverse environmental locations, and many species need to shift their physiology between different niches. to do this effectively requires the accurate sensing of and response to the environment. for pathogens, exposure to light is one major change between a free-living saprophyte lifestyle and causation of disease within the host. however, how light may act as a signal to influence pathogenesis, on the side of either the host or the pathogen, is poorly understood. research duri ...201323631920
pyrg is required for maintaining stable cellular uracil level and normal sporulation pattern under excess uracil stress in aspergillus nidulans.tight control of the intracellular uracil level is believed to be important to reduce the occurrence of uracil incorporation into dna. the pyrg gene of aspergillus nidulans encodes orotidine 5'-phosphate decarboxylase, which catalyzes the conversion of orotidine monophosphate (omp) to uridine monophosphate (ump). in this study, we found that pyrg is critical for maintaining uracil at a low concentration in a. nidulans cells in the presence of exogenous uracil. excess uracil and its derivatives h ...201323633078
β-glucan synthase gene overexpression and β-glucans overproduction in pleurotus ostreatus using promoter swapping.mushroom β-glucans are potent immunological stimulators in medicine, but their productivities are very low. in this study, we successfully improved its production by promoter engineering in pleurotus ostreatus. the promoter for β-1,3-glucan synthase gene (gls) was replaced by the promoter of glyceraldehyde-3-phosphate dehydrogenase gene of aspergillus nidulans. the homologous recombination fragment for swapping gls promoter comprised five segments, which were fused by two rounds of combined touc ...201323637884
loss of ccla, required for histone 3 lysine 4 methylation, decreases growth but increases secondary metabolite production in aspergillus fumigatus.secondary metabolite (sm) production in filamentous fungi is mechanistically associated with chromatin remodeling of specific sm clusters. one locus recently shown to be involved in sm suppression in aspergillus nidulans was ccla, a member of the histone 3 lysine 4 methylating compass complex. here we examine loss of ccla and a putative h3k4 demethylase, hdma, in the human pathogen aspergillus fumigatus. although deletion of hdma showed no phenotype under the conditions tested, the ccla deletant ...201323638376
conf and conj contribute to conidia germination and stress response in the filamentous fungus aspergillus nidulans.light induces various responses in fungi including formation of asexual and sexual reproductive structures. the formation of conidia in the filamentous fungus aspergillus nidulans is regulated by red and blue light receptors. expression of conidia associated con genes, which are widely spread in the fungal kingdom, increases upon exposure to light. we have characterized the light-inducible conf and conj genes of a. nidulans which are homologs of con-6 and con-10 of neurospora crassa. con genes a ...201323644150
invasive fungal infections in patients with chronic granulomatous disease.invasive fungal infections are a major threat for chronic granulomatous disease (cgd) patients. the present study provides a comprehensive overview of published invasive fungal infections in the cgd host through an extensive review of epidemiological, clinical, diagnostic and therapeutic data. in addition to the often mild clinical presentation, the currently used diagnostics for invasive aspergillosis have low sensitivity in cgd patients and cannot be easily translated to this non-neutropenic h ...201323654055
identification of metabolic pathways influenced by the g-protein coupled receptors gprb and gprd in aspergillus nidulans.heterotrimeric g-protein-mediated signaling pathways play a pivotal role in transmembrane signaling in eukaryotes. our main aim was to identify signaling pathways regulated by a. nidulans gprb and gprd g-protein coupled receptors (gpcrs). when these two null mutant strains were compared to the wild-type strain, the δgprb mutant showed an increased protein kinase a (pka) activity while growing in glucose 1% and during starvation. in contrast, the δgprd has a much lower pka activity upon starvatio ...201323658706
base composition and nucleosome density in exonic and intronic regions in genes of the filamentous ascomycetes aspergillus nidulans and aspergillus oryzae.we sequenced nucleosomal dna fragments of the filamentous ascomycetes aspergillus nidulans and aspergillus oryzae and then mapped those sequences on their genomes. we compared the gc content and nucleosome density in the exonic and intronic regions in the genes of a. nidulans and a. oryzae. although the gc content and nucleosome density in the exonic regions tended to be higher than those in the intronic regions, the difference in the distribution of the gc content was more notable than that of ...201323664982
genetic bypass of aspergillus nidulans crza function in calcium homeostasis.after dephosphorylation by the phosphatase calcineurin, the fungal transcription factor crza enters the nucleus and activates the transcription of genes responsible for calcium homeostasis and many other calcium-regulated activities. a lack of crza confers calcium-sensitivity to the filamentous fungus aspergillus nidulans. to further understand calcium signaling in filamentous fungi and to identify genes that interact genetically with crza, we selected for mutations that were able to suppress cr ...201323665873
rsma regulates aspergillus fumigatus gliotoxin cluster metabolites including cyclo(l-phe-l-ser), a potential new diagnostic marker for invasive aspergillosis.dimeric basic leucine zipper (bzip) proteins are conserved transcriptional enhancers found in all eukaryotes. a recently reported and novel function for bzips is association of these proteins with secondary metabolite production in filamentous fungi. in particular a yap-like bzip termed rsma (restorer of secondary metabolism a) was identified in aspergillus nidulans that positively regulates the carcinogen sterigmatocystin. to assess for conserved function for rsma, we examined a role of this pr ...201323671611
differences in composition of honey samples and their impact on the antimicrobial activities against drug multiresistant bacteria and pathogenic fungi.antibiotic multiresistant microbes represent a challenging problem. because honey has a potent antibacterial property, the antimicrobial effects of different honey samples against multiresistant pathogens and their compositions were investigated.201323684665
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
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
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
multicenter study of isavuconazole mic distributions and epidemiological cutoff values for aspergillus spp. for the clsi m38-a2 broth microdilution method.epidemiological cutoff values (ecvs) were established for the new triazole isavuconazole and aspergillus species wild-type (wt) mic distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) that were defined with 855 aspergillus fumigatus, 444 a. flavus, 106 a. nidulans, 207 a. niger, 384 a. terreus, and 75 a. versicolor species complex isolates; 22 aspergillus section usti isolates were also included. clsi broth microdilution mic data gathered in ...201323716059
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
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
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
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
genetic and structural validation of aspergillus fumigatus udp-n-acetylglucosamine pyrophosphorylase as an antifungal target.the sugar nucleotide udp-n-acetylglucosamine (udp-glcnac) is an essential metabolite in both prokaryotes and eukaryotes. in fungi, it is the precursor for the synthesis of chitin, an essential component of the fungal cell wall. udp-n-acetylglucosamine pyrophosphorylase (uap) is the final enzyme in eukaryotic udp-glcnac biosynthesis, converting utp and n-acetylglucosamine-1-phosphate (glcnac-1p) to udp-glcnac. as such, this enzyme may provide an attractive target against pathogenic fungi. here, w ...201323750903
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
discovery of cryptic polyketide metabolites from dermatophytes using heterologous expression in aspergillus nidulans.dermatophytes belonging to the trichophyton and arthroderma genera cause skin infections in humans and animals. from genome sequencing data, we mined a conserved gene cluster among dermatophytes that are homologous to one that produces an immunosuppressive polyketide in aspergillus fumigatus. using a recombination-based cloning strategy in yeast, we constructed fungal heterologous expression vectors that encode the cryptic clusters. when integrated into the model aspergillus nidulans host, a str ...201323758576
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
gβ-like cpcb plays a crucial role for growth and development of aspergillus nidulans and aspergillus fumigatus.growth, development, virulence and secondary metabolism in fungi are governed by heterotrimeric g proteins (g proteins). a gβ-like protein called gib2 has been shown to function as an atypical gβ in gpa1-camp signaling in cryptococcus neoformans. we found that the previously reported cpcb (cross pathway control b) protein is the ortholog of gib2 in aspergillus nidulans and aspergillus fumigatus. in this report, we further characterize the roles of cpcb in governing growth, development and toxige ...201323936193
an acidic thermostable recombinant aspergillus nidulans endoglucanase is active towards distinct agriculture residues.aspergillus nidulans is poorly exploited as a source of enzymes for lignocellulosic residues degradation for biotechnological purposes. this work describes the a. nidulans endoglucanase a heterologous expression in pichia pastoris, the purification and biochemical characterization of the recombinant enzyme. active recombinant endoglucanase a (reg a) was efficiently secreted as a 35 kda protein which was purified through a two-step chromatography procedure. the highest enzyme activity was detecte ...201323936633
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
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
determination of isavuconazole susceptibility of aspergillus and candida species by the eucast method.isavuconazole is a novel expanded-spectrum triazole, which has recently been approved by the fda as an orphan drug to treat invasive aspergillosis and is currently being studied in phase iii clinical trials for invasive candidiasis. the susceptibility of relatively few clinical isolates has been reported. in this study, the isavuconazole susceptibilities of 1,237 aspergillus and 2,010 candida geographically diverse clinical isolates were determined by eucast methodology at four european mycology ...201323959309
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
molecular genetics of emericella nidulans sexual development.many aspergilli that belongs to ascomycetes have sexuality. in a homothallic or self-fertile fungus, a number of fruiting bodies or cleistothecia are formed in a thallus grown from a single haploid conidia or ascospores. genome-sequencing project revealed that two mating genes (mat) encoding the regulatory proteins that are necessary for controlling partner recognition in heterothallic fungi were conserved in most aspergilli. the mat gene products in some self-fertile species were not required f ...200923983529
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
aspergillus flavus velb acts distinctly from vea in conidiation and may coordinate with flug to modulate sclerotial production.the proteins vea, velb and laea of aspergillus nidulans form a heterotrimeric complex (the velvet complex) in the dark to coordinate sexual development and production of some secondary metabolites. vea and velb of a. nidulans and aspergillus fumigatus also are repressors of conidiation, but vea of aspergillus flavus in studied strains acts positively on conidiation. in the present study, we show via yeast-two hybrid assays that interactions among a. flavus vea, velb, and laea are conserved as in ...201323994319
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
ecological and physiological studies on soil fungi at western region, libya.sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-czapek's agar at 28℃. the most common genera were alternaria, aspergillus, emericella, fusarium, mycosphaerella, nectria and penicillium. the most prevalent species from the three types of soils on the three types of media ...200823997599
effect of some food preservatives on the lipolytic activity of beef luncheon fungi.beef luncheon meat is one of the most popular meals in several countries in the world including egypt. thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in qena. alternaria, aspergillus, emericella, mucor, mycosphaerella, penicillium and rhizopus were the most common genera on the two types of media. from the above genera, the most prevalent species were alternaria alternate, aspergillus flavus, a. fumigat ...200823997619
topical application of preparations containing dna repair enzymes prevents ultraviolet-induced telomere shortening and c-fos proto-oncogene hyperexpression in human skin: an experimental pilot study.the exposure to ultraviolet radiation (uvr) is one of the most important risk factors for skin aging and increases the risk of malignant transformation. telomere shortening and an altered expression of the proto-oncogene c-fos are among the key molecular mechanisms associated with photoaging and tumorigenesis. photolyase from a. nidulans and endonuclease from m. luteus are xenogenic dna repair enzymes which can reverse the molecular events associated with skin aging and carcinogenosis caused by ...201324002149
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
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
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
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
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
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
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
mechanism of sterigmatocystin biosynthesis regulation by ph in aspergillus nidulans.external ph constitutes one of the most important environmental factors that control growth, metabolism and differentiation in microorganisms, including fungi. we have analyzed the effect of external ph on sterigmatocystin biosynthesis in aspergillus nidulans. it was observed in repeated experiments that alkaline ph, in opposition to acid ph, increased sterigmatocystin production and the transcript levels of aflr, the master gene that regulates expression of the sterigmatocystin cluster in a. ni ...200924031444
cytological characterization of an aspergillus nidulans mutant from a strain with chromosomic duplication.a development mutant, named v103, was obtained spontaneously from the a strain of a. nidulans. the a strain contains a duplicated segment of chromosome i that has undergone translocation to chromosome ii (i ii). it is mitotically unstable and generates phenotypically deteriorated types, some with enhanced stability. the deteriorated variants of a. nidulans show abnormal development, exhibiting slower colony growth, variations in colony pigmentation and changes in conidiophore structure. the alte ...201024031489
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
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
occurrence of fungal species and mycotoxins from decayed sugarcane (saccharrum officinarum) in egypt.seventy-three fungal species belonging to forty-three genera were isolated from 40 samples of saccharrum officinarum (collected from naage-hamadi canal in qena governorate, egypt). aspergillus, trichoderma, mucor and pythium were the most common genera on the two isolation media. the dominant species of aspergillus were a. niger, a. flavus, a. ustus, a. terreus and a. wentii. some species were dominant on 40 g/l sucrose such as aspergillus niger, a. flavus, emericella nidulans, trichoderma virid ...200524049478
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
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
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
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
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
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
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
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
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
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
gfsa encodes a novel galactofuranosyltransferase involved in biosynthesis of galactofuranose antigen of o-glycan in aspergillus nidulans and aspergillus fumigatus.the cells walls of filamentous fungi in the genus aspergillus have galactofuranose (galf)-containing polysaccharides and glycoconjugates, including o-glycans, n-glycans, fungal-type galactomannan and glycosylinositolphosphoceramide, which are important for cell wall integrity. here, we attempted to identify galactofuranosyltransferases that couple galf monomers onto other wall components in aspergillus nidulans. using reverse-genetic and biochemical approaches, we identified that the an8677 gene ...201324118544
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
aspergillus collagen-like genes (acl): identification, sequence polymorphism, and assessment for pcr-based pathogen detection.the genus aspergillus is a burden to public health due to its ubiquitous presence in the environment, its production of allergens, and wide demographic susceptibility among cystic fibrosis, asthmatic, and immunosuppressed patients. current methods of detection of aspergillus colonization and infection rely on lengthy morphological characterization or nonstandardized serological assays that are restricted to identifying a fungal etiology. collagen-like genes have been shown to exhibit species-spe ...201324123732
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
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
targeting fungal genes by diced sirnas: a rapid tool to decipher gene function in aspergillus nidulans.gene silencing triggered by chemically synthesized small interfering rnas (sirnas) has become a powerful tool for deciphering gene function in many eukaryotes. however, prediction and validation of a single sirna duplex specific to a target gene is often ineffective. rna interference (rnai) with synthetic sirna suffers from lower silencing efficacy, off-target effects and is cost-intensive, especially for functional genomic studies. with the explosion of fungal genomic information, there is an i ...201324130711
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
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
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 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
transcription of the rrna gene cluster in aspergillus nidulanss.transcription of rdna in aspergillus nidulans was examined by hybridizing labeled cloned rdna fragments to blots of rna gels. one processing pathway was found.198324173152
suppressible alleles in a wide domain regulatory gene in aspergillus nidulans.the area gene of aspergillus nidulans is a one of the better studied eukaryotic wide domain regulatory genes, necessary for the expression of most structural genes involved in the utilization of a wide variety of nitrogen sources (arst and cove 1973; arst 1983). here we report the isolation and properties of area alleles suppressible by translational suppressors (roberts et al. 1979). thus we show formally that the area gene specifies a protein rather than an rna product and we show that it is p ...198424177791
regulation of two alcohol dehydrogenases in aspergillus nidulans.in aspergillus nidulans there are two alcohol dehydrogenases. in the presence of ethanol, alcohol dehydrogenase i (ahh i) is induced and alcohol dehydrogenase ii (adh ii) is repressed. adh i and adh ii have molecular weights of 39,000 and 36,000 respectively. at least adh i is under the control of alcr, a transacting regulatory gene that is adjacent to alca (the structural gene for adh i, pateman et al. 1983). mutations in the alcr regulatory gene result in non inducibility of adh i specific mrn ...198424177792
a mitochondrial reading frame which may code for a second form of atpase subunit 9 in aspergillus nidulans.the nucleotide sequence of a 74 codon reading frame from the aspergillus nidulans mitochondrial genome is presented. the derived amino acid sequence displays typical features of dicyclohexylcarbodiimide (dccd) binding proteins and is 84% homologous with a mitochondrial reading frame that potentially encodes an atpase subunit 9 polypeptide in neurospora crassa. however, in a. nidulans, as in n. crassa, there is strong biochemical and genetic evidence that this subunit is in fact nuclearly-encoded ...198424177948
mutations to constitutivity and derepression are separate and separable in a regulatory gene of aspergillus nidulans.previous work has shown that expression of the structural genes for the enzymes of nitrate and nitrite assimilation in aspergillus nidulans requires the products of two positively acting regulatory genes - nira, mediating induction, and area, mediating nitrogen metabolite repression. here we show that, in addition to previously described mutations in nira leading to constitutivity, other mutations can be selected in nira leading to nitrogen metabolite derepression. these constitutivity and depre ...198124185869
cloning and analysis of recombinant plasmids containing genes for aspergillus nidulans 5 s rrna.genes coding for 5s rrna were found to be dispersed in the aspergillus nidulans genome. three different recombinant plasmids hybridizing to 5s rrna were isolated and their restriction enzyme maps were established.198124185988
genetic map of mitochondrial dna in podospora anserina.in order to develop an eukaryotic vector with the podospora plasmid, further characterization is required of the mitochondrial dna into which this plasmid is integrated, a physical map (restriction sites) of the podospora chondriome (size 95 kb) has been completed. as prerequisite for the establishment of a genetic (functional) map, 70% of the chondriome was cloned in e. coli vectors. using mitochondrial genes from saccharomyces cerevisiae, six structural genes were located on the podospora chon ...198224186230
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