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gfsa is a β1,5-galactofuranosyltransferase involved in the biosynthesis of the galactofuran side chain of fungal-type galactomannan inaspergillus fumigatus.previously, we reported that gfsa is a novel galactofuranosyltransferase involved in the biosynthesis of o-glycan, the proper maintenance of fungal morphology, the formation of conidia and anti-fungal resistance in aspergillus nidulans and a. fumigatus (komachi y et al., mol. microbiol. 90, 1054-1073, 2013). in the present paper, to gain an in depth-understanding of the enzymatic functions of gfsa in a. fumigatus (afgfsa), we established an in vitro assay to measure galactofuranosyltransferase a ...201728369326
cpsa regulates mycotoxin production, morphogenesis and cell wall biosynthesis in the fungus aspergillus nidulans.the model fungus aspergillus nidulans synthesizes numerous secondary metabolites, including sterigmatocystin (st). the production of this toxin is positively controlled by the global regulator vea. in the absence of vea (δvea), st biosynthesis is blocked. previously we performed random mutagenesis in a δvea strain and identified revertant mutants able to synthesize st, among them rm1. complementation of rm1 with a genomic library revealed that the mutation occurred in a gene designated as cpsa. ...201728370587
evaluation of the in vitro activity of isavuconazole and comparator voriconazole against 2635 contemporary clinical candida and aspergillus isolates.the in vitro activity of isavuconazole was determined for 1677 candida and 958 aspergillus isolates from 2012 to 2014 with voriconazole as comparator.201728373148
genetic studies on the physiological role of corvet in aspergillus nidulans.corvet and hops are protein complexes mediating the maturation of early endosomes (ees) into late endosomes (les)/vacuoles. these hetero-hexamers share four 'core' components, vps11, vps16, vps18 and vps33, and differ in two specific subunits, corvet vps8 and vps3 and hops vps39 and vps41. whereas ablating hops-specific components has minor growth effects, ablating any corvet constituent severely debilitates aspergillus nidulans growth, buttressing previous work indicating that maturation of ees ...201728379362
elucidation of biosynthetic pathways of natural products.during the last decade, we have revealed biosynthetic pathways responsible for the formation of important and chemically complex natural products isolated from various organisms through genetic manipulation. detailed in vivo and in vitro characterizations enabled elucidation of unexpected mechanisms of secondary metabolite biosynthesis. this personal account focuses on our recent efforts in identifying the genes responsible for the biosynthesis of spirotryprostatin, aspoquinolone, sch 210972, py ...201728387469
involvement of a velvet protein clvelb in the regulation of vegetative differentiation, oxidative stress response, secondary metabolism, and virulence in curvularia lunata.the ortholog of aspergillus nidulans velb, which is known as clvelb, was studied to gain a broader insight into the functions of a velvet protein in curvularia lunata. with the expected common and specific functions of clvelb, the deletion of clvelb results in similar though not identical phenotypes. the pathogenicity assays revealed that δclvelb was impaired in colonizing the host tissue, which corresponds to the finding that clvelb controls the production of conidia and the methyl 5-(hydroxyme ...201728393907
comparative transcriptome sequence analysis of sporulation-related genes of aspergillus cristatus in response to low and high osmolarity.aspergillus cristatus undergoes sexual and asexual development under conditions of low and high osmotic pressure, respectively. in this study, the expression levels of 107 genes associated with sexual and asexual development were analysed under conditions of low and high osmotic pressure by rna sequencing. the results showed that 37 genes were up-regulated and other genes were down-regulated under conditions of high osmotic pressure, with most of the up-regulated genes associated with asexual de ...201728417188
sporulation: how to survive on planet earth (and beyond).sporulation is a strategy widely utilized by a wide variety of organisms to adapt to changes in their individual environmental niches and survive in time and/or space until they encounter conditions acceptable for vegetative growth. the spores produced by bacteria have been the subjects of extensive studies, and several systems such as bacillus subtilis have provided ample opportunities to understand the molecular basis of spore biogenesis and germination. in contrast, the spores of other microb ...201728421279
differential control of asexual development and sterigmatocystin biosynthesis by a novel regulator in aspergillus nidulans.the filamentous fungus aspergillus nidulans primarily reproduces by forming asexual spores called conidia and produces the mycotoxin sterigmatocystin (st), the penultimate precursor of aflatoxins. it has been known that asexual development and st production are tightly co-regulated by various regulatory inputs. here, we report that the novel regulator asla with a c2h2 domain oppositely regulates development and st biosynthesis. nullifying asla resulted in defective conidiation and reduced expres ...201728422127
interrelationships of vel1 and env1 in light response and development in trichoderma reesei.sexual development is regulated by a complex regulatory mechanism in fungi. for trichoderma reesei, the light response pathway was shown to impact sexual development, particularly through the photoreceptor envoy. moreover, t. reesei communicates chemically with a potential mating partner in its vicinity, a response which is mediated by the velvet family protein vel1 and its impact on secondary metabolism. we therefore studied the regulatory interactions of env1 and vel1 with a focus on sexual de ...201728423024
napa mediates a redox regulation of the antioxidant response, carbon utilization and development in aspergillus nidulans.the redox-regulated transcription factors (tfs) of the bzip ap1 family, such as yeast yap1 and fission yeast pap1, are activated by peroxiredoxin proteins (prxs) to regulate the antioxidant response. previously, aspergillus nidulans mutants lacking the yap1 ortholog napa have been characterized as sensitive to h2o2 and menadione. here we study napa roles in relation to tfs srra and atfa, also involved in oxidant detoxification, showing that these tfs play different roles in oxidative stress resi ...201728424666
aspergillus flavus aswa, a gene homolog of aspergillus nidulans oefc, regulates sclerotial development and biosynthesis of sclerotium-associated secondary metabolites.aspergillus flavus aswa (afla_085170) is a gene encoding a zn(ii)2cys6 dna-binding domain and a transcriptional activation domain, duf3468. disruption of aswa yielded strains that made a truncated gene transcript and generated a fungus that produced a greatly increased number of sclerotia. these sclerotia were odd-shaped and non-pigmented (white) and different from oval and pigmented (dark brown to black) mature sclerotia. transcriptomic analysis of the δaswa strain grown on potato dextrose agar ...201728442441
conservation and diversity of the regulators of cellulolytic enzyme genes in ascomycete fungi.in the past decade, various transcriptional activators of cellulolytic enzyme genes have been identified in ascomycete fungi. the regulatory system of cellulolytic enzymes is not only partially conserved, but also significantly diverse. for example, trichoderma reesei has a system distinct from those of aspergillus and neurospora crassa-the former utilizes xyr1 (the aspergillus xlnr ortholog) as the major regulator of cellulolytic enzyme genes, while the latter uses clr-2/clrb/manr orthologs. xl ...201728451846
rtfa controls development, secondary metabolism, and virulence in aspergillus fumigatus.invasive aspergillosis by aspergillus fumigatus is a leading cause of infection-related mortality in immune-compromised patients. in order to discover potential genetic targets to control a. fumigatus infections we characterized rtfa, a gene encoding a putative rna polymerase ii transcription elongation factor-like protein. our recent work has shown that the rtfa ortholog in the model fungus aspergillus nidulans regulates morphogenesis and secondary metabolism. the present study on the opportuni ...201728453536
sirtuin e is a fungal global transcriptional regulator that determines the transition from the primary growth to the stationary phase.in response to limited nutrients, fungal cells exit the primary growth phase, enter the stationary phase, and cease proliferation. although fundamental to microbial physiology in many environments, the regulation of this transition is poorly understood but likely involves many transcriptional regulators. these may include the sirtuins, which deacetylate acetyllysine residues of histones and epigenetically regulate global transcription. therefore, we investigated the role of a nuclear sirtuin, si ...201728465348
the quinoline bromoquinol exhibits broad-spectrum antifungal activity and induces oxidative stress and apoptosis in aspergillus fumigatus.over the last 30 years, the number of invasive fungal infections among immunosuppressed patients has increased significantly, while the number of effective systemic antifungal drugs remains low. the aim of this study was to identify and characterize antifungal compounds that inhibit fungus-specific metabolic pathways not conserved in humans.201728475687
the role of vosa/velb-activated developmental gene vada in aspergillus nidulans.the filamentous fungus aspergillus nidulans primarily reproduces by forming asexual spores called conidia, the integrity of which is governed by the nf-κb type velvet regulators vosa and velb. the vosa-velb hetero-complex regulates the expression of spore-specific structural and regulatory genes during conidiogenesis. here, we characterize one of the vosa/velb-activated developmental genes, called vada, the expression of which in conidia requires activity of both vosa and velb. vada (an5709) is ...201728481894
proteomics as a tool to identify new targets against aspergillus and scedosporium in the context of cystic fibrosis.cystic fibrosis (cf) is a genetic disorder that increases the risk of suffering microbial, including fungal, infections. in this paper, proteomics-based information was collated relating to secreted and cell wall proteins with potential medical applications from the most common filamentous fungi in cf, i.e., aspergillus and scedosporium/lomentospora species. among the aspergillus fumigatus secreted allergens, β-1,3-endoglucanase, the alkaline protease 1 (alp1/oryzin), asp f 2, asp f 13/15, chiti ...201728484941
structure and function of a broad-specificity chitin deacetylase from aspergillus nidulans fgsc a4.enzymatic conversion of chitin, a β-1,4 linked polymer of n-acetylglucosamine, is of major interest in areas varying from the biorefining of chitin-rich waste streams to understanding how medically relevant fungi remodel their chitin-containing cell walls. although numerous chitinolytic enzymes have been studied in detail, relatively little is known about enzymes capable of deacetylating chitin. we describe the structural and functional characterization of a 237 residue deacetylase (ancda) from ...201728496100
pulses of ca(2+) coordinate actin assembly and exocytosis for stepwise cell extension.many eukaryotic cells grow by extending their cell periphery in pulses. the molecular mechanisms underlying this process are not yet fully understood. here we present a comprehensive model of stepwise cell extension by using the unique tip growth system of filamentous fungi. live-cell imaging analysis, including superresolution microscopy, revealed that the fungus aspergillus nidulans extends the hyphal tip in an oscillatory manner. the amount of f-actin and secretory vesicles (sv) accumulating ...201728507141
nmea, a novel efflux transporter specific for nucleobases and nucleosides, contributes to metal resistance in aspergillus nidulans.through minos transposon mutagenesis we obtained a. nidulans mutants resistant to 5-fluorouracil due to insertions into the upstream region of the uncharacterized gene nmea, encoding a major facilitator superfamily (mfs) transporter. minos transpositions increased nmea transcription, which is otherwise extremely low under all conditions tested. to dissect the function of nmea we used strains overexpressing or genetically lacking the nmea gene. strains overexpressing nmea are resistant to toxic p ...201728509393
a cryptic pigment biosynthetic pathway uncovered by heterologous expression is essential for conidial development in pestalotiopsis fici.spore pigmentation is very common in the fungal kingdom. the best studied pigment in fungi is melanin which coats the surface of single cell spores. what and how pigments function in a fungal species with multiple cell conidia is poorly understood. here, we identified and deleted a polyketide synthase (pks) gene pfmae and showed that it is essential for multicellular conidial pigmentation and development in a plant endophytic fungus, pestalotiopsis fici. to further characterize the melanin pathw ...201728517364
erratum: differential control of asexual development and sterigmatocystin biosynthesis by a novel regulator in aspergillus nidulans. 201728548131
the lectin chaperone calnexin is involved in the endoplasmic reticulum stress response by regulating ca(2+) homeostasis in aspergillus nidulans.the ca(2+)-mediated signaling pathway is crucial for environmental adaptation in fungi. here we show that calnexin, a molecular chaperone located in the endoplasmic reticulum (er), plays an important role in regulating the cytosolic free calcium concentration ([ca(2+)]c) in aspergillus nidulans inactivation of calnexin (clxa) in a. nidulans caused severe defects in hyphal growth and conidiation under er stress caused by the er stress-inducing agent dithiothreitol (dtt) or high temperature. impor ...201728550061
cop9 signalosome subunit pfcsne regulates secondary metabolism and conidial formation in pestalotiopsis fici.the cop9 signalosome (csn) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. in filamentous fungi, several lines of evidence indicate that fungal development and secondary metabolism (sm) are mediated by the fifth subunit of csn, called csne. here we uncover a connection with csne and conidial formation as well as sm regulation in the plant endophytic fungus pestalotiopsis fici. a homology search of the p. fici genome with csne, invo ...201728550524
expression system for heterologous protein expression in the filamentous fungus aspergillus unguis.heterologous protein expression in filamentous fungi is advantageous, especially in the context of large scale production of high volume low value recombinant proteins. however, such systems are rare and not available in public domain. a novel filamentous fungus - aspergillus unguis nii 08123 was used as host for developing a protein expression system. an expression cassette was assembled using a. nidulans glyceraldehyde 3 phosphate dehydrogenase promoter (pgapd), tryptophan synthase transcripti ...201728578805
a mechanism for a single nucleotide intron shift.spliceosomal introns can occupy nearby rather than identical positions in orthologous genes (intron sliding or shifting). stwintrons are complex intervening sequences, where an 'internal' intron interrupts one of the sequences essential for splicing, generating after its excision, a newly formed canonical intron defined as 'external'. in one experimentally demonstrated configuration, two alternatively excised internal introns, overlapping by one g, disrupt respectively the donor and the acceptor ...201728595329
a scalable platform to identify fungal secondary metabolites and their gene clusters.the genomes of filamentous fungi contain up to 90 biosynthetic gene clusters (bgcs) encoding diverse secondary metabolites-an enormous reservoir of untapped chemical potential. however, the recalcitrant genetics, cryptic expression, and unculturability of these fungi prevent scientists from systematically exploiting these gene clusters and harvesting their products. as heterologous expression of fungal bgcs is largely limited to the expression of single or partial clusters, we established a scal ...201728604695
in vitro activity of the novel antifungal compound f901318 against difficult-to-treat aspergillus isolates.f901318 is a new antifungal agent with a novel mechanism of action with activity against aspergillus species. we investigated the in vitro activity of f901318 against a collection of aspergillus isolates.201728605488
identification and heterologous production of a benzoyl-primed tricarboxylic acid polyketide intermediate from the zaragozic acid a biosynthetic pathway.zaragozic acid a (1) is a potent cholesterol lowering, polyketide natural product made by various filamentous fungi. the reconstitution of enzymes responsible for the initial steps of the biosynthetic pathway of 1 is accomplished using an engineered fungal heterologous host. these initial steps feature the priming of a benzoic acid starter unit onto a highly reducing polyketide synthase (hrpks), followed by oxaloacetate extension and product release to generate a tricarboxylic acid containing pr ...201728605916
copper resistance in aspergillus nidulans relies on the pi-type atpase crpa, regulated by the transcription factor acea.copper homeostasis has been extensively studied in mammals, bacteria, and yeast, but it has not been well-documented in filamentous fungi. in this report, we investigated the basis of copper tolerance in the model fungus aspergillus nidulans. three genes involved in copper homeostasis have been characterized. first, crpa the a. nidulans ortholog of candida albicans cacrp1 gene encoding a pi-type atpase was identified. the phenotype of crpa deletion led to a severe sensitivity to cu(+2) toxicity ...201728611736
antifungal activity against filamentous fungi of ts1, a multifunctional toxin from tityus serrulatus scorpion venom.antimicrobial peptides (amps) are ubiquitous and multipotent components of the innate immune defense arsenal used by both prokaryotic and eukaryotic organisms. the search for new amps has increased in recent years, due to the growing development of microbial resistance to therapeutical drugs. in this work, we evaluate the effects of tityus serrulatus venom (tsv), its fractions and its major toxin ts1, a beta-neurotoxin, on fungi growth. the fractions were obtained by ion-exchange chromatography ...201728634472
the aspergillus nidulans velvet-interacting protein, vipa, is involved in light-stimulated heme biosynthesis.filamentous fungi are able to differentiate morphologically and adapt the metabolism to internal and external cues. one major regulator is the so-called velvet protein, vea, best studied in aspergillus nidulans. the protein interacts with several other proteins to regulate light sensing, the balance between asexual and sexual development, penicillin biosynthesis or mycotoxin production. here, we characterized a novel vea-interacting protein, vipa. the 334 amino acid long protein comprises a far1 ...201728657694
sirtuin a regulates secondary metabolite production by aspergillus nidulans.late-stage cultures of filamentous fungi under nutrient starvation produce valuable secondary metabolites such as pharmaceuticals and pigments, as well as deleterious mycotoxins, all of which have remarkable structural diversity and wide-spectrum bioactivity. the fungal mechanisms regulating the synthesis of many of these compounds are not fully understood, but sirtuin a (sira) is a key factor that initiates production of the secondary metabolites, sterigmatocystin and penicillin g, by aspergill ...201728674377
the gata-type transcription factor csm1 regulates conidiation and secondary metabolism in fusarium fujikuroi.gata-type transcription factors (tfs) such as the nitrogen regulators area and areb, or the light-responsive tfs wc-1 and wc-2, play global roles in fungal growth and development. the conserved gata tf nsdd is known as an activator of sexual development and key repressor of conidiation in aspergillus nidulans, and as light-regulated repressor of macroconidia formation in botrytis cinerea. in the present study, we functionally characterized the nsdd ortholog in fusarium fujikuroi, named csm1. del ...201728694801
steroid 11-alpha-hydroxylation by the fungi aspergillus nidulans and aspergillus ochraceus.steroids are a group of natural compounds derived from the cyclopentane-perhydro-phenantrene nucleus that have a great interest for the pharmaceutical industries as a consequence of their physiological effects. among their functions are anti-inflammatory, immunosuppressive, or contraceptive activities. nowadays, microbial transformation of steroid precursors is winning relevance opposite to the chemical synthesis, since it allows for decreasing time, expenses, and environmental pollution. pharma ...201728710635
coupling the pretreatment and hydrolysis of lignocellulosic biomass by the expression of beta-xylosidases.thermochemical pretreatment and enzymatic hydrolysis are the areas contributing most to the operational costs of second generation ethanol in lignocellulosic biorefineries. the improvement of lignocellulosic enzyme cocktails has been significant in the recent years. although the needs for the reduction of the energy intensity and chemical consumption in the pretreatment step are well known, the reduction of the severity of the process strongly affects the enzymatic hydrolysis yield. to explore t ...201728710860
a robust high-throughput fungal biosensor assay for the detection of estrogen activity.estrogenic active compounds are present in a variety of sources and may alter biological functions in vertebrates. therefore, it is crucial to develop innovative analytical systems that allow us to screen a broad spectrum of matrices and deliver fast and reliable results. we present the adaptation and validation of a fungal biosensor for the detection of estrogen activity in cow derived samples and tested the clinical applicability for pregnancy diagnosis in 140 mares and 120 cows. as biosensor ...201728712952
deletion of the cela gene in aspergillus nidulans triggers overexpression of secondary metabolite biosynthetic genes.although much progress has been made in the study of cell wall biosynthetic genes in the model filamentous fungus aspergillus nidulans, there are still targets awaiting characterization. an example is the gene cela (ania_08444) encoding a putative mixed linkage glucan synthase. to characterize the role of cela, we deleted it in a. nidulans, analyzed the phenotype of the mycelium and performed rna-seq. the strain shows a very strong phenotype, namely "balloons" along the hyphae and aberrant conid ...201728729615
prevention of melanin formation during aryl alcohol oxidase production under growth-limited conditions using an aspergillus nidulans cell factory.an aspergillus nidulans cell factory was genetically engineered to produce an aryl alcohol oxidase (aao). the cell factory initiated production of melanin when growth-limited conditions were established using stationary plates and shaken flasks. this phenomenon was more pronounced when the strain was cultured in a trickle bed reactor (tbr). this study investigated different approaches to reduce melanin formation in fungal mycelia and liquid medium in order to increase the enzyme production yield ...201728738504
defensive repertoire of drosophila larvae in response to toxic fungi.chemical warfare including insecticidal secondary metabolites is a well-known strategy for environmental microbes to monopolize a food source. insects in turn have evolved behavioural and physiological defences to eradicate or neutralize the harmful microorganisms. we studied the defensive repertoire of insects in this interference competition by combining behavioural and developmental assays with whole-transcriptome time-series analysis. confrontation with the toxic filamentous fungus aspergill ...201728746736
mitotic nuclear pore complex segregation involves nup2 in aspergillus nidulans.transport through nuclear pore complexes (npcs) during interphase is facilitated by the nucleoporin nup2 via its importin α- and ran-binding domains. however, aspergillus nidulans and vertebrate nup2 also locate to chromatin during mitosis, suggestive of mitotic functions. in this study, we report that nup2 is required for mitotic npc inheritance in a. nidulans interestingly, the role of nup2 during mitotic npc segregation is independent of its importin α- and ran-binding domains but relies on a ...201728747316
a matter of scale and dimensions: chromatin of chromosome landmarks in the fungi.chromatin and chromosomes of fungi are highly diverse and dynamic, even within species. much of what we know about histone modification enzymes, rna interference, dna methylation, and cell cycle control was first addressed in saccharomyces cerevisiae, schizosaccharomyces pombe, aspergillus nidulans, and neurospora crassa. here, we examine the three landmark regions that are required for maintenance of stable chromosomes and their faithful inheritance, namely, origins of dna replication, telomere ...201728752814
boron tolerance in aspergillus nidulans is sustained by the slta pathway through the slc-family transporters sbta and sbtb.microbial cells interact with the environment by adapting to external changes. signal transduction pathways participate in both sensing and responding in the form of modification of gene expression patterns, enabling cell survival. the filamentous fungal-specific slta pathway regulates tolerance to alkalinity, elevated cation concentrations and, as shown in this work, also stress conditions induced by borates. growth of slta(-) mutants is inhibited by increasing millimolar concentrations of bori ...201728753996
molecular basis for the unusual ring reconstruction in fungal meroterpenoid biogenesis.trt14 from aspergillus terreus is involved in unusual skeletal reconstruction during the biosynthesis of the fungal meroterpenoid terretonin. detailed in vitro characterization revealed that this novel multifunctional enzyme catalyzes not only the d-ring expansion via intramolecular methoxy rearrangement, but also the hydrolysis of the expanded d-ring. the x-ray crystal structures of trt14, in complex with substrate or product, and two trt14 homologs, aush and prhc from aspergillus nidulans and ...201728759016
transcriptome-based modeling reveals that oxidative stress induces modulation of the atfa-dependent signaling networks in aspergillus nidulans.to better understand the molecular functions of the master stress-response regulator atfa in aspergillus nidulans, transcriptomic analyses of the atfa null mutant and the appropriate control strains exposed to menadione sodium bisulfite- (msb-), t-butylhydroperoxide- and diamide-induced oxidative stresses were performed. several elements of oxidative stress response were differentially expressed. many of them, including the downregulation of the mitotic cell cycle, as the msb stress-specific upr ...201728770220
microtubule-organizing centers of aspergillus nidulans are anchored at septa by a disordered protein.microtubule-organizing centers (mtocs) are large, multi-subunit protein complexes. schizosaccharomyces pombe harbors mtocs at spindle pole bodies, transient mtocs in the division plane (emtocs) and nuclear-envelope associated mtocs in interphase cells (imtocs). in the filamentous fungus aspergillus nidulans spbs and septum-associated mtocs were described. although comparable to s. pombe emtocs, a. nidulans smtocs are permanent septum-associated structures. the composition of smtocs is poorly und ...201728787538
molecular cloning, structural modeling and production of recombinant aspergillus terreusl. asparaginase in escherichia coli.l-asparaginase (ec 3.5.1.1) is an important medical enzyme that catalysis the hydrolysis of l-asparagine to aspartic acid and ammonium. for over four decades l. asparaginase utic agent for the treatment of a variety of lymphoproliferative disorders and lymphoma such as acute lymphoblastic leukemia. in the present study a. terreus full length l. asparaginase gene, 1179bp was optimized for expression in escherichia coli bl21 (de3) plyss. the full length a. terreusl. asparaginase gene encoding a pr ...201728851634
aspergillus nidulans baph is a rab11 effector that connects membranes in the spitzenkörper with basal autophagy.using affinity chromatography we identified the aspergillus nidulans f-bar-and-ph domain-containing protein baph as a rabe(rab11) effector. baph localizes to the spitzenkörper (spk) in an f-actin- and sec7-dependent manner, becoming cytosolic after inactivation of trs120 in trappii, the oligomeric gef for rabe(rab11) . therefore rabe(rab11) contributes to the recruitment of baph to secretory vesicles in vivo. baph has a close homologue, slma, which is related to yeast slm1p/slm2p, localizes to e ...201728857357
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