PMID(sorted ascending)
onset of carbon catabolite repression in aspergillus nidulans. parallel involvement of hexokinase and glucokinase in sugar signaling.the role of hexose phosphorylating enzymes in the signaling of carbon catabolite repression was investigated in the filamentous fungus aspergillus nidulans. a d-fructose non-utilizing, hexokinase-deficient (hxka1, formerly designated fra1) strain was utilized to obtain new mutants lacking either glucokinase (glka4) or both hexose kinases (hxka1/glka4). d-glucose and d-fructose phosphorylation is completely abolished in the double mutant, which consequently cannot grow on either sugar. the glucok ...200312519784
carbon and ph modulate the expression of the fungal glucose repressor encoding genes.the phytopathogenic necrotrophic fungus sclerotinia sclerotiorum secretes large amounts of oxalic acid and cell wall-degrading enzymes (cwde). enzyme synthesis is ph dependent and subject to carbon catabolite repression. because of the possible involvement of the glucose repressor cre1 in the transcriptional control of the cwde encoding genes, we studied crel expression with respect to the nature of the extracellular carbon source and the value of the external ph. comparative analysis of the cre ...200312520371
a cellulose-binding module of the trichoderma reesei beta-mannanase man5a increases the mannan-hydrolysis of complex substrates.endo-beta-1,4-d-mannanases (beta-mannanase; ec are endohydrolases that participate in the degradation of hemicellulose, which is closely associated with cellulose in plant cell walls. the beta-mannanase from trichoderma reesei (man5a) is composed of an n-terminal catalytic module and a c-terminal carbohydrate-binding module (cbm). in order to study the properties of the cbm, a construct encoding a mutant of man5a lacking the part encoding the cbm (man5adeltacbm), was expressed in t. re ...200312523968
interaction of the mitotic inhibitor monastrol with human kinesin eg5.the microtubule-dependent kinesin-like protein eg5 from homo sapiens is involved in the assembly of the mitotic spindle. it shows a three-domain structure with an n-terminal motor domain, a central coiled coil, and a c-terminal tail domain. in vivo hseg5 is reversibly inhibited by monastrol, a small cell-permeable molecule that causes cells to be arrested in mitosis. both monomeric and dimeric eg5 constructs have been examined in order to define the minimal monastrol binding domain on hseg5. nmr ...200312525161
a new identity for mlk3 as an nima-related, cell cycle-regulated kinase that is localized near centrosomes and influences microtubule organization.although conserved counterparts for most proteins involved in the g(2)/m transition of the cell cycle have been found in all eukaryotes, a notable exception is the essential but functionally enigmatic fungal kinase nima. while a number of vertebrate kinases have been identified with catalytic domain homology to nima, none of these resemble nima within its extensive noncatalytic region, a region critical for nima function in aspergillus nidulans. we used a bioinformatics approach to search for pr ...200312529434
the antifungal protein from aspergillus giganteus causes membrane permeabilization.we investigated the inhibitory effects of the antifungal protein (afp) from aspergillus giganteus on the growth of several filamentous fungi. for this purpose, the mics of afp were determined and ranged from 0.1 micro g/ml for fusarium oxysporum to 200 micro g/ml for aspergillus nidulans. the antifungal activity of afp was diminished in the presence of cations. we were able to show that incubation of afp-sensitive fungi with the protein resulted in membrane permeabilization using an assay based ...200312543664
[research on the regulation of glucoamylase gene(glaa) expression in a. niger. ii. analysis of the function of 5'-regulatory region of a. niger t21 and 3.795 glaa gene].two plasmid vectors pxh2 and pgh1 were constructed through the fusion of e. coli hph gene, the report gene and the 5' upstream regions of a. niger t21 and 3.795 respectively, as well as the terminator of a. nidulans trpc gene. the plasmid vectors were than used to transform a. niger t21 to functionally identify those different basic groups between the two 5' upstream regions responsible for high-level expression of the glaa gene. southern analysis of two transformants xh2c and gh1c revealed that ...199812549385
sequence comparison of aflr from different aspergillus species provides evidence for variability in regulation of aflatoxin production.aflatoxin contamination of foods and feeds is a world-wide agricultural problem. aflatoxin production requires expression of the biosynthetic pathway regulatory gene, aflr, which encodes a cys6zn2-type dna-binding protein. homologs of aflr from aspergillus nomius, bombycis, parasiticus, flavus, and pseudotamarii were compared to investigate the molecular basis for variation among aflatoxin-producing taxa in the regulation of aflatoxin production. variability was found in putative promoter consen ...200312553937
testing the limits of biological tolerance to arsenic in a fungus isolated from the river tinto.the tinto river in spain, with its high acidity and heavy metal concentrations (as, cu, cr, zn), is an example of an environment hostile to life. yet despite these extreme conditions, the site possesses a great diversity of eukaryotic life forms. we report the isolation of a filamentous fungus able to grow at 200 mm arsenic ( approximately 15 000 p.p.m.), i.e. a concentration 20-fold above that withstood by the reference microorganisms escherichia coli, saccharomyces cerevisiae and aspergillus n ...200312558596
in plants the alc gene expression system responds more rapidly following induction with acetaldehyde than with has recently been proposed that acetaldehyde is the physiological inducer of the alc gene system and hence indirectly the activator of the alca promoter in aspergillus nidulans. here we show that this chemical induces expression of a gus (beta-d-glucuronidase) reporter under the control of the alc gene system in transgenic potato tubers more rapidly than ethanol allowing tighter control of transgene expression. furthermore by analysis of metabolite levels we demonstrate that the application o ...200312560092
cloning and expression analysis of the pcbab-pcbc beta-lactam genes in the marine fungus kallichroma we report the identification of the beta-lactam biosynthesis genes pcbab and pcbc from a cosmid genomic dna library of the marine fungus kallichroma tethys. a blast homology search showed that they share high sequence identity with the delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) synthetases and isopenicillin n synthases, respectively, of various fungal and bacterial beta-lactam producers, while phylogenetic analysis indicated a close relationship with homologous genes of the ceph ...200312571064
sex and the single gene: meiotic silencing by unpaired dna. 200212571367
area directly mediates nitrogen regulation of gibberellin biosynthesis in gibberella fujikuroi, but its activity is not affected by nmr.area (nit2) is a general transcription factor involved in derepression of numerous genes responsible for nitrogen utilization in gibberella fujikuroi and many other fungi. we have previously shown that the deletion of area-gf resulted in mutants with significantly reduced gibberellin (ga) production. here we demonstrate that the expression level of six of the seven ga biosynthesis genes is drastically reduced in mutants lacking area. furthermore, we show that, despite the fact that gas are nitro ...200312581353
activation mechanisms of the hac1-mediated unfolded protein response in filamentous fungi.the unfolded protein response (upr) is a regulatory pathway activating genes involved in multiple functions related to folding, quality control and transport of secreted proteins. characterization of the hac1/haca genes encoding the upr transcription factors from the filamentous fungi trichoderma reesei and aspergillus nidulans is described in this article. the corresponding gene in saccharomyces cerevisiae is activated through a non-spliceosomal intron-splicing reaction. the t. reesei hac1 and ...200312581366
expression of the ech42 (endochitinase) gene of trichoderma atroviride under carbon starvation is antagonized via a brla-like cis-acting element.expression of the endochitinase encoding ech42 gene of the mycoparasite trichoderma atroviride is subject to control by several environmental signals, including derepression by carbon starvation. in order to identify promoter areas involved in control by this condition, we prepared fusions of several mutant forms of the ech42 promoter to the aspergillus niger goxa gene as a reporter. removal of a 130-bp fragment comprising a binding site for the carbon catabolite repressor cre1, an agggg element ...200312586401
ypxl/i is a protein interaction motif recognized by aspergillus pala and its human homologue, aip1/alix.the zinc finger transcription factor pacc undergoes two-step proteolytic activation in response to alkaline ambient ph. pala is a component of the fungal ambient ph signal transduction pathway. its mammalian homologue aip1/alix interacts with the apoptosis-linked protein alg-2. we show that both pala and aip1/alix recognize a protein-protein binding motif that we denote ypxl/i, where tyr, pro, and leu/ile are crucial for its interactive properties. two such motifs flanking the signaling protease ...200312588984
deletion of aspergillus nidulans aroc using a novel blaster module that combines et cloning and marker rescue.blaster cassettes are of significant value in functional genomics, as they represent tools with which to inactivate duplicated or homologous genes in an individual organism. we have constructed a novel blaster module which allows repeated gene deletion in the filamentous fungus aspergillus nidulans. because bacterial resistance marker cassettes are employed as flanking repeats in direct orientation, the blaster cassette is suited for recombinogenic engineering by et cloning in escherichia coli. ...200312589442
impact of the cross-pathway control on the regulation of lysine and penicillin biosynthesis in aspergillus nidulans.the non-proteinogenic amino acid, alpha-aminoadipate, defines the biosynthetic branch-point of lysine and penicillin biosynthesis in the filamentous fungus, aspergillus nidulans. regulation of both pathways was analysed in response to amino acid limitation. the lysf-encoded homoaconitase acts upstream of the alpha-aminoadipate branch point, whereas the lysa gene product, saccharopine dehydrogenase, catalyses the ultimate step of the lysine-specific branch. the lysa gene from a. nidulans was iden ...200312589472
development of a transformation system for crinipellis perniciosa, the causal agent of witches' broom in cocoa plants.protoplasts of the pathogenic plant fungus, crinipellis perniciosa, were transformed to hygromycin b resistance using the pan7-1 plasmid, which contains the escherichia coli hph gene under the control of aspergillus nidulans regulatory sequences. the pan7-1 plasmid was introduced by peg/cacl(2) treatment. transformation frequencies of 1.6-2.5 transformants/microg of dna were achieved. about 54% of the transformants were abortive and 40 analyzed transformants were mitotically stable and showed di ...200312589475
broad and complex antifungal activity among environmental isolates of lactic acid bacteria.more than 1200 isolates of lactic acid bacteria isolated from different environments were screened for antifungal activity in a dual-culture agar plate assay. approximately 10% of the isolates showed inhibitory activity and 4% showed strong activity against the indicator mould aspergillus fumigatus. the antifungal spectra for 37 isolates with strong activity and five isolates with low or no activity were determined. several of the strains showed strong inhibitory activity against the moulds a. f ...200312594034
identification of the pathogenic aspergillus species by nested pcr using a mixture of specific primers to dna topoisomerase ii gene.for pcr-based identification of aspergillus species, a common primer of the dna topoisomerase ii genes of candida, aspergillus and penicillium, and species-specific primers of the genomic sequences of dna topoisomerase ii of a. fumigatus, a. niger, a. flavus (a. oryzae), a. nidulans and a. terreus were tested for their specificities in pcr amplifications. the method consisted of amplification of the genomic dna topoisomerase ii gene by a common primer set, followed by a second pcr with a primer ...200212597358
use of green fluorescent protein to quantify the growth of colletotrichum during infection of develop a quantitative assay of fungal growth inside plant tissues, strains of colletotrichum destructivum and colletotrichum orbiculare were transformed with a modified green fluorescent protein (gfp) gene fused with a glyceraldehyde-3-phosphate dehydrogenase promoter from aspergillus nidulans. transformants expressed gfp in culture and had the same growth rate and general appearance as the wild type. gfp was observed in all fungal structures during infection of leaves of nicotiana benthamia ...200312609730
ligand-induced conformational changes and a mechanism for domain closure in aspergillus nidulans dehydroquinate order to investigate systematically substrate and cofactor-induced conformational changes in the enzyme dehydroquinate synthase (dhqs), eight structures representing a series of differently liganded states have been determined in a total of six crystal forms. dhqs in the absence of the substrate analogue carbaphosphonate, either unliganded or in the presence of nad or adp, is in an open form where a relative rotation of 11-13 degrees between n and c-terminal domains occurs. analysis of torsio ...200312614613
control of morphogenesis and actin localization by the penicillium marneffei rac homolog.rac proteins control polarized growth in many organisms but the specific function of these proteins remains undefined. in this study, we describe the cloning and functional characterization of a rac homolog, cflb, from the dimorphic fungus penicillium marneffei. p. marneffei produces asexual spores on complex structures (conidiophores) and switches between hyphal and yeast growth. cflb colocalizes with actin at the tips of vegetative hyphal cells and at sites of cell division. deletion of cflb r ...200312615967
primary structure of cytochrome c gene from the white root rot fungus rosellinia necatrix.the nucleotide sequence of the cytochrome c (cytc) gene of the white root rot fungus rosellinia necatrix was analyzed. the structure of this gene, which had three introns in the coding region, was similar to that of aspergillus nidulans. the second intron of the r. necatrix cytc gene was not present in neurospora crassa or fusarium oxysporum. however, the amino acid sequence of r. necatrix was most similar to that of neurospora crassa. thus, it seemed that the second intron of the r. necatrix cy ...200312619691
regulation of expression of the rhizopus oryzae uricase and urease enzymes.the regulation of intracellular urease and uricase activities was examined in rhizopus oryzae. urease activity (2.4 u/mg protein) was present in r. oryzae mycelium grown in minimal medium containing nh4ci as sole nitrogen source. this activity increased threefold under nitrogen derepression conditions, but no induction by urea was detected. control of urease activity in r. oryzae differs from that found in neurospora crassa but resembles the situation in aspergillus nidulans. no uricase activity ...200212619824
specific induction and carbon/nitrogen repression of arginine catabolism gene of aspergillus nidulans--functional in vivo analysis of the otaa promoter.the arginine catabolism gene otaa encoding ornithine transaminase (otase) is specifically induced by arginine and is under the control of the broad-domain carbon and nitrogen repression systems. arginine induction is mediated by a product of arca gene coding for zn(2)c(6) activator. we have identified a region responsible for arginine induction in the otaa promoter (anuas(arg)). deletions within this region result in non-inducibility of otase by arginine, whether in an arca(+) strain or in the p ...200312620254
mutation in a calpain-like protease affects the posttranslational mannosylation of phosphatases in aspergillus this communication, we show that the palb7 mutation drastically reduced the mannose and n-acetylgalactosamine content of the paca-encoded acid phosphatase secreted by the fungus aspergillus nidulans at ph 5.0, compared to a control strain. by using mrna differential display reverse transcription and polymerase chain reaction, we isolated two cdnas from the control pabaa1 strain that were not detected in the palb7 mutant strain that encode a mannosyl transferase and a nadh-ubiquinone oxidoredu ...200312620258
expression of the mnpa gene that encodes the mannoprotein of aspergillus nidulans is dependent on fada and flba as well as vea.the single copy mnpa gene that encodes a mannoprotein of aspergillus nidulans and its cdna were isolated from the genomic and cdna libraries, respectively. the determined nucleotide sequences of the genomic dna and its cdna revealed that the gene has an open-reading frame of 261 amino acids without introns. the deduced amino acid sequence showed a 60% identity to that of aspegillus fumigatus galactomannoprotein mp1. the mnpa gene was expressed more abundantly in the wild-type than in the vea-nul ...200312620259
conidial hydrophobins of aspergillus fumigatus.the surface of aspergillus fumigatus conidia, the first structure recognized by the host immune system, is covered by rodlets. we report that this outer cell wall layer contains two hydrophobins, rodap and rodbp, which are found as highly insoluble complexes. the roda gene was previously characterized, and deltaroda conidia do not display a rodlet layer (n. thau, m. monod, b. crestani, c. rolland, g. tronchin, j. p. latgé, and s. paris, infect. immun. 62:4380-4388, 1994). the rodb gene was clone ...200312620846
the mapkk kinase stec regulates conidiophore morphology and is essential for heterokaryon formation and sexual development in the homothallic fungus aspergillus nidulans.environmental signals can be transduced into intracellular responses by the action of map kinase cascades. sequential phosphorylation results in the transient activation of a map kinase, which in turn activates certain transcription factors and thus a set of pathway-specific genes. many steps in this cascade are conserved, and homologues have been discovered from yeast to human. we have characterized the mapkk kinase, stec, a homologue of saccharomyces cerevisiae ste11, in the filamentous fungus ...200312622813
in vitro susceptibility testing of aspergillus spp.: comparison of etest and reference microdilution methods for determining voriconazole and itraconazole mics.the performance of the etest for voriconazole and for itraconazole susceptibility testing of 376 isolates of aspergillus spp. was assessed in comparison with the national committee for clinical laboratory standards (nccls) proposed standard microdilution broth method. the nccls method employed rpmi 1640 broth medium, and mics were read after incubation for 48 h at 35 degrees c. etest mics were determined with rpmi agar containing 2% glucose and were read after incubation for 48 h at 35 degrees c ...200312624040
roles of nude and nudf proteins of aspergillus nidulans: insights from intracellular localization and overexpression effects.the nudf protein of the filamentous fungus aspergillus nidulans functions in the cytoplasmic dynein pathway. it binds several proteins, including the nude protein. green fluorescent protein-tagged nudf and nuda (dynein heavy chain) localize to linearly moving dashes ("comets") that coincide with microtubule ends. herein, deletion of the nude gene did not eliminate the comets of nudf and nuda, but affected the behavior of nuda. comets were also observed with the green fluorescent protein-tagged n ...200312631710
fungistatic activity of semecarpus anacardium linn. f nut extract.alcoholic extract of dry nuts of s. anacardium showed dose dependent antifungal activity in vitro against aspergillus fumigatus and candida albicans. at 400 mg/ml concentration, growth of both the fungi was inhibited and considerable reduction in size of cells and hyphae was observed. sporulation also decreased.200212635702
primary structure of the histone 2b gene in the white root rot fungus, rosellinia necatrix.the nucleotide sequence of the histone 2b (h2b) gene in the white root rot fungus, rosellinia necatrix, was determined. the gene has two introns in the coding region at positions conserved in the neurospora crassa and aspergillus nidulans h2b genes, but the third intron present in the h2b gene from n. crassa and a. nidulans is absent in the r. necatrix h2b gene. the amino acid sequence of the coding region of the r. necatrix gene resembled that of n. crassa and a. nidulans. therefore, the third ...200212652911
in vitro analysis of the relationship between endonuclease and maturase activities in the bi-functional group i intron-encoded protein, i-anii.the ancob group i intron from aspergillus nidulans encodes a homing dna endonuclease called i-anii which also functions as a maturase, assisting in ancob intron rna splicing. in this investigation we biochemically characterized the endonuclease activity of i-anii in vitro and utilized competition assays to probe the relationship between the rna- and dna-binding sites. despite functioning as an rna maturase, i-anii still retains several characteristic properties of homing endonucleases including ...200312654010
tupa, the penicillium marneffei tup1p homologue, represses both yeast and spore development.fungal pathogenesis is frequently associated with dimorphism - morphological changes between yeast and filamentous forms. penicillium marneffei, an opportunistic human pathogen, exhibits temperature-dependent dimorphism, with growth at 25 degrees c as filamentous multinucleate hyphae switching at 37 degrees c to uninucleate yeast cells associated with intracellular pathogenesis. the filamentous hyphae also undergo asexual development generating uninucleate spores, the infectious propagules. both ...200312657047
the npga/ cfwa gene encodes a putative 4'-phosphopantetheinyl transferase which is essential for penicillin biosynthesis in aspergillus nidulans.non-ribosomal peptide synthetases, polyketides and fatty acid synthetases have a modular organisation of multi-enzymatic activities. in all of them, the acyl or peptidyl carrier proteins have 4'-phosphopantetheine (p-pant) as an essential prosthetic group. this is added by 4'-phosphopantetheinyl transferases (pptases) that derive the p-pant group from coenzyme a. while many pptases of varying specificity have now been isolated from a number of bacteria, a filamentous fungal pptase has yet to be ...200312664133
activation of chsc transcription by abaa during asexual development of aspergillus nidulans.the temporal and spatial regulation of chitin synthesis plays an important role in morphogenesis during fungal growth and development. northern blot analysis showed that the transcription level of chsa, chsc, and chsd was significantly decreased in an aspergillus nidulans abaa mutant. electrophoretic mobility shift assays revealed that abaa bound tightly to all three ares (abaa response elements) in the chsc promoter region. experiments with the saccharomyces cerevisiae heterologous expression s ...200312670687
role for nudc, a dynein-associated nuclear movement protein, in mitosis and cytokinesis.nudc, a nuclear movement protein that associates with dynein, was originally cloned as a mitogen-inducible early growth response gene. nudc forms a biochemical complex with components of the dynein/dynactin complex and is suggested to play a role in translocation of nuclei in proliferating neuronal progenitors as well as in migrating neurons in culture. here, we show that nudc plays multiple roles in mitosis and cytokinesis in cultured mammalian cells. altering nudc levels by either small interf ...200312679384
femoral osteomyelitis due to aspergillus nidulans in a patient with chronic granulomatous disease.13 cases of osteomyelitis caused by aspergillus nidulans have been previously reported in patients with chronic granulomatous disease (cgd). all of them have been associated with simultaneous pulmonary infection and have had an extremely poor outcome. we report an unusual case of femoral osteomyelitis due to a. nidulans in a 16-year-old male with cgd, without pulmonary involvement. treatment with liposomal amphotericin b and granulocyte colony-stimulating factor as well as extensive surgical deb ...200312682820
ph regulation in aspergillus and parallels with higher eukaryotic regulatory systems.all organisms respond to their environment to some extent, and for many microbes the variation in environment can be enormous. an important asset for coping with environmental variation is physiological versatility--a hallmark of many fungi. the ability of fungi to thrive over a wide range of ph is partly due to a genetic regulatory system that tailors gene expression to the ambient ph. here we focus on the ph regulatory system of aspergillus nidulans, where a novel signal transduction (pal) pat ...200312683976
circadian and light-induced expression of luciferase in neurospora crassa.we have constructed a plasmid vector for expressing firefly luciferase in neurospora crassa under control of the light- and clock-regulated ccg-2 (eas) promoter. the sequence of the luciferase gene in the vector has been modified to reflect the n. crassa codon bias. both light-induced activity and circadian activity are demonstrated. expression of luciferase in strains carrying mutant frequency alleles shows appropriate period length alterations. these data demonstrate that luciferase is a sensi ...200312684022
nuclear import of zinc binuclear cluster proteins proceeds through multiple, overlapping transport aspergillus nidulans, the high transcriptional level of the ethanol utilization pathway genes (alc) is regulated by the specific activator alcr. here we have analyzed the mechanism of the nuclear import of alcr, as well as that of other proteins belonging to the zn(2)cys(6) binuclear cluster family. the nuclear localization signal of alcr maps within the n-terminal 75 amino acid residues and overlaps with its dna-binding domain. it consists of five clusters rich in basic residues. four of the ...200312684370
a circadian oscillator in aspergillus spp. regulates daily development and gene expression.we have established the presence of a circadian clock in aspergillus flavus and aspergillus nidulans by morphological and molecular assays, respectively. in a. flavus, the clock regulates an easily assayable rhythm in the development of sclerotia, which are large survival structures produced by many fungi. this developmental rhythm exhibits all of the principal clock properties. the rhythm is maintained in constant environmental conditions with a period of 33 h at 30 degrees c, it can be entrain ...200312684372
accumulation of cytoplasmic dynein and dynactin at microtubule plus ends in aspergillus nidulans is kinesin dependent.the mechanism(s) by which microtubule plus-end tracking proteins are targeted is unknown. in the filamentous fungus aspergillus nidulans, both cytoplasmic dynein and nudf, the homolog of the lis1 protein, localize to microtubule plus ends as comet-like structures. herein, we show that nudm, the p150 subunit of dynactin, also forms dynamic comet-like structures at microtubule plus ends. by examining proteins tagged with green fluorescent protein in different loss-of-function mutants, we demonstra ...200312686603
clnr1, the area/nit2-like global nitrogen regulator of the plant fungal pathogen colletotrichum lindemuthianum is required for the infection cycle.nitrogen starvation is generally assumed to be encountered by biotrophic and hemibiotrophic plant fungal pathogens at the beginning of their infection cycle. we tested whether nitrogen starvation constitutes a cue regulating genes that are required for pathogenicity of colletotrichum lindemuthianum, a fungal pathogen of common bean. the clnr1 (c. lindemuthianumnitrogen regulator 1) gene, the area/nit-2 orthologue of c. lindemuthianum, was isolated. the predicted clnr1 protein exhibits high amino ...200312694611
the ph signalling transcription factor pacc controls virulence in the plant pathogen fusarium oxysporum.gene expression in fungi by ambient ph is regulated via a conserved signalling cascade whose terminal component is the zinc finger transcription factor pacc/rim1p. we have identified a pacc orthologue in the vascular wilt pathogen fusarium oxysporum that binds the consensus 5'-gccaag-3' sequence and is proteolytically processed in a similar way to pacc from aspergillus nidulans. pacc transcript levels were elevated in f. oxysporum grown in alkaline conditions and almost undetectable at extreme a ...200312694620
promoter analysis of the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum in the model filamentous fungus aspergillus nidulans.the promoter of avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum contains 12 sequences within a region of 0.6 kb that are reminiscent of the binding sequences of the gata-type regulator involved in nitrogen utilisation of the filamentous fungi aspergillus nidulans and neurospora crassa. mutational analysis of this 0.6-kb promoter region, fused to the beta-glucuronidase reporter gene, revealed that two regions, each containing two tagata boxes in inverted orientation and ove ...200312695849
telomeric repeat sequence of aspergillus oryzae consists of dodeca-nucleotides.four telomeres in the chromosomes of aspergillus oryzae nfri1599 were cloned and sequenced. the telomeric repeat sequence of a. oryzae consisted of dodeca-nucleotides: ttagggtcaaca. the length of the telomeric repeat tract was 114-136 bp, which corresponds to 9-11 repeats of the dodeca-nucleotide sequence. compared to a chromosome internal control (18s rdna), the telomeric sequences were found to be sensitive to bal31 exonuclease digestion, thus proving that the identified telomeric repeat seque ...200312698283
mycotoxins of aspergilli: exposure and health effects.mycotoxins derived from aspergilli can be encountered both in domestic and occupational environments, and the exposure may lead to severe health hazards. several aspergillus species are associated with mycotoxin production: a. ochraceus with ochratoxin a, a. fumigatus with fumitremorgins, gliotoxin and verrucologen, a. versicolor with sterigmatocystin, and a. flavus and a. parasiticus with aflatoxins. sterigmatocystin may also be produced by a. flavus, a. nidulans, a. rugulosus, and a. unguis. e ...200312700107
the isopenicillin n acyltransferases of aspergillus nidulans and penicillium chrysogenum differ in their ability to maintain the 40-kda alphabeta heterodimer in an undissociated form.the isopenicillin n acyltransferases (iats) of aspergillus nidulans and penicillium chrysogenum differed in their ability to maintain the 40-kda proacyltransferase alphabeta heterodimer in an undissociated form. the native a. nidulans iat exhibited a molecular mass of 40 kda by gel filtration. the p. chrysogenum iat showed a molecular mass of 29 kda by gel filtration (corresponding to the beta subunit of the enzyme) but the undissociated 40-kda heterodimer was never observed even in crude extrac ...200312709055
in vitro susceptibility of aspergillus spp. clinical isolates to albendazole.the in vitro antifungal activity of albendazole, a benzimidazole widely used as an antihelmintic drug in humans, was investigated and assessed for its activity against aspergillus spp. forty-eight isolates, representing the most frequent species found in human pathology [aspergillus fumigatus (n = 27), aspergillus flavus (n = 10), aspergillus terreus (n = 7), aspergillus nidulans (n = 3) and aspergillus niger (n = 1)], and one quality control strain (a. niger atcc 9804 83435) were tested accordi ...200312716778
heterologous expression of laccase cdna from ceriporiopsis subvermispora yields copper-activated apoprotein and complex isoform patterns.analysis of genomic clones encoding a putative laccase in homokaryon strains of ceriporiopsis subvermispora led to the identification of an allelic variant of the previously described lcs-1 gene. a cdna clone corresponding to this gene was expressed in aspergillus nidulans and in aspergillus niger. enzyme assays and western blots showed that both hosts secreted active laccase. relative to the isozymic forms of the native c. subvermispora enzyme, the a. niger-produced laccase had a higher molecul ...200312724379
in vitro susceptibility testing of filamentous fungi: comparison of etest and reference m38-a microdilution methods for determining posaconazole mics.the performance of the etest for posaconazole susceptibility testing of 72 isolates of filamentous fungi was assessed in comparison with the national committee for clinical laboratory standards (nccls) approved standard broth microdilution method (m38-a). the nccls method employed rpmi 1640 broth medium, and mics were read after incubation for 48h at 35 degrees c. etest mics were determined with rpmi agar containing 2% glucose and were read after incubation for 48h at 35 degrees c. the isolates ...200312729993
deletion of mdmb impairs mitochondrial distribution and morphology in aspergillus nidulans.mitochondria form a dynamic network of interconnected tubes in the cells of saccharomyces cerevisiae or filamentous fungi such as aspergillus nidulans, neurospora crassa, or podospora anserina. the dynamics depends on the separation of mitochondrial fragments, their movement throughout the cell, and their subsequent fusion with the other parts of the organelle. interestingly, the microtubule network is required for the distribution in n. crassa and s. pombe, while s. cerevisiae and a. nidulans a ...200312740872
never say never. the nima-related protein kinases in mitotic control.mitosis sees a massive reorganization of cellular architecture. the microtubule cytoskeleton is reorganized to form a bipolar spindle between duplicated microtubule organizing centers, the chromosomes are condensed, attached to the spindle at their kinetochores, and, through the action of multiple molecular motors, the chromosomes are segregated into two daughter cells. mitosis also sees a substantial wave of protein phosphorylation, controlling signaling events that coordinate mitotic processes ...200312742165
cloning and functional expression of an esterase gene in aspergillus parasitcus.within the 80 kb aflatoxin pathway gene cluster characterized earlier, and between adha and nora genes, we have identified an esta gene encoding an esterase from wild type strain aspergillus parasiticus srrc 143. the 1,500 bp genomic dna and 945 bp cdna sequences were determined for esta. outside of the aflatoxin pathway gene cluster, an additional copy of the esta gene (named esta2) was also cloned from the same a. parasiticus strain. comparison of the esta and esta2 sequences showed 9 substitu ...200212749588
molecular characterization and analysis of the acrb gene of aspergillus nidulans: a gene identified by genetic interaction as a component of the regulatory network that includes the creb deubiquitination enzyme.mutations in the acrb gene, which were originally selected through their resistance to acriflavine, also result in reduced growth on a range of sole carbon sources, including fructose, cellobiose, raffinose, and starch, and reduced utilization of omega-amino acids, including gaba and beta-alanine, as sole carbon and nitrogen sources. the acrb2 mutation suppresses the phenotypic effects of mutations in the creb gene that encodes a regulatory deubiquitinating enzyme, and in the crec gene that enco ...200312750323
functionally distinct nucleic acid binding sites for a group i intron encoded rna maturase/dna homing endonuclease.a large number of group i introns encode a family of homologous proteins that either promote intron splicing (maturases) or are site-specific dna endonucleases that function in intron mobility (a process called "homing"). genetic studies have shown that some of these proteins have both activities, yet how a single protein carries out both functions remains obscure. the similarity between respective dna-binding sites and the rna structure near the 5' and 3' splice sites has fueled speculation tha ...200312758073
structural and functional characterisation of the dna binding domain of the aspergillus nidulans gene regulatory protein area.the 876-aa protein area regulates the expression of numerous genes involved in nitrogen metabolism in aspergillus nidulans, and interacts with gata sequences upstream of the relevant genes. we have carried out limited proteolysis of the c-terminal domain of the area protein in order to identify possible structural domains within the protein. a stable 156-amino-acid fragment was identified that contained the zinc finger region, and this sequence was cloned and expressed in e. coli. fluorescence s ...200312758150
molecular genetics of fungal siderophore biosynthesis and uptake: the role of siderophores in iron uptake and acquire iron, all species have to overcome the problems of iron insolubility and toxicity. in response to low iron availability in the environment, most fungi excrete ferric iron-specific chelators--siderophores--to mobilize this metal. siderophore-bound iron is subsequently utilized via the reductive iron assimilatory system or uptake of the siderophore-iron complex. furthermore, most fungi possess intracellular siderophores as iron storage compounds. molecular analysis of siderophore biosyn ...200312759789
catalases of aspergillus fumigatus.upon infection of a host, the pathogenic fungus aspergillus fumigatus is attacked by the reactive oxygen species produced by phagocytic cells. detoxification of hydrogen peroxide by catalases was proposed as a way to overcome this host response. a. fumigatus produces three active catalases; one is produced by conidia, and two are produced by mycelia. the mycelial catalase cat1p was studied previously. here we characterized the two other catalases, their genes, and the phenotypes of gene-disrupte ...200312761140
molecular characterisation and expression analysis of the first hemicellulase gene (bxl1) encoding beta-xylosidase from the thermophilic fungus talaromyces emersonii.the gene coding for beta-xylosidase, bxl1, has been cloned from the thermophilic filamentous fungus, talaromyces emersonii. this is the first report of a hemicellulase gene from this novel source. at the genomic level, bxl1 consists of an open reading frame of 2388 nucleotides with no introns that encodes a putative protein of 796 amino acids. the bxl1 translation product contains a signal peptide of 21 amino acids that yields a mature protein of 775 amino acids, with a predicted molecular mass ...200312763033
the negative transcriptional regulator nmra discriminates between oxidized and reduced dinucleotides.nmra, a transcription repressor involved in the regulation of nitrogen metabolism in aspergillus nidulans,is a member of the short-chain dehydrogenase reductase superfamily. isothermal titration calorimetry and differential scanning calorimetry have been used to show nmra binds nad+ and nadp+ with similar affinity (average kd 65 microm) but has a greatly reduced affinity for nadh and nadph (average kd 6.0 mm). the structure of nmra in a complex with nadp+ reveals how repositioning a his-37 side ...200312764138
biosynthesis of pyridoxine in saccharomyces cerevisiae--origin of the pyridoxine nitrogen atom differs under anaerobic and aerobic conditions.the amide nitrogen atom of glutamine is incorporated into pyridoxine in four eukaryotes (i.e., emericella nidulans, mucor racemosus, neurospora crassa and saccharomyces cerevisiae) and two prokaryotes (i.e., staphylococcus aureus and bacillus subtilis). however, in the prokaryotes pseudomonas putida, enterobacter aerogenes and escherichia coli, it is the nitrogen atom of glutamate that is incorporated into pyridoxine (j nutr sci vitaminol (2000) 46, 55-57). as these results were from experiments ...200212775110
male and female roles in crosses of aspergillus nidulans as revealed by vegetatively incompatible resolve the role of male and female nuclei and mitochondria in cleistothecium formation in the model organism aspergillus nidulans, we analysed the genetic constituents of cleistothecia from crosses between vegetatively compatible and incompatible parents. we used markers that enabled us to determine the nuclear genotype of the cleistothecial wall and the nuclear and mitochondrial genotype of the ascospores. in compatible parents, nuclear genomes and cytoplasm usually mix in the vegetative hy ...200312781672
alternative oxidase expression in neurospora crassa.when electron flow through the cytochrome-mediated electron transport chain is blocked by inhibitors or mutations, the mitochondria of neurospora crassa contain a kcn-insensitive alternative oxidase, encoded by the aod-1 gene, that transfers electrons directly from the ubiquinone pool to oxygen. the mechanism by which the enzyme is induced is unknown. comparison of the sequence upstream of the n. crassa aod-1 gene with the corresponding region of gelasinospora spp. and aspergillus nidulans revea ...200312781676
expression of a synthetic copy of the bovine chymosin gene in aspergillus awamori from constitutive and ph-regulated promoters and secretion using two different pre-pro sequences.a copy of the bovine chymosin gene (chy) with a codon usage optimized for its expression in aspergillus awamori was constructed starting from synthetic oligonucleotides. to study the ability of this filamentous fungus to secrete bovine prochymosin, two plasmids were constructed in which the transcriptional, translational, and secretory control regions of the a. nidulans gpda gene and pepb genes were coupled to either preprochymosin or prochymosin genes. secretion of a protein enzymatically and i ...200312783481
surface hydrophobicity of aspergillus nidulans conidiospores and its role in pellet formation.formation of pellets by aspergillus nidulans is primarily due to agglomeration of the fungal conidiospores. although agglomeration of conidiospores has been known for a long time, its mechanism has not been clearly elucidated. to study the influence of the fungal conidiospore wall hydrophobicity on conidiospore agglomeration, pellet formation of an a. nidulans wild type and strains deleted in the conidiospore-wall-associated hydrophobins dewa and roda was compared at different ph values. from co ...200312790678
different roles of the mre11 complex in the dna damage response in aspergillus nidulans.the mre11-rad50-nbs1 protein complex has emerged as a central player in the cellular dna damage response. mutations in scaanbs1, which encodes the apparent homologue of human nbs1 in aspergillus nidulans, inhibit growth in the presence of the anti-topoisomerase i drug camptothecin. we have used the scaanbs1 cdna as a bait in a yeast two-hybrid screening and report the identification of the a. nidulans mre11 homologue (mrea). the inactivated mrea strain was more sensitive to several dna damaging ...200312791148
expression of the red fluorescent protein dsred-express in filamentous ascomycete fungi.the recently reported red fluorescent protein dsred from the reef coral discosoma sp. represents a new marker that has been codon-optimized for high expression in mammalian cells. to facilitate expression of dsred in ascomycete fungi, we used the clone pdsred-express (clontech) for constructing a plasmid vector, ppgpd-dsred, containing the constitutive aspergillus nidulans glyceraldehyde 3-phosphate (gpd) promoter. this vector was used for co-transformation of penicillium paxilli, trichoderma ha ...200312799012
spindle formation in aspergillus is coupled to tubulin movement into the many important organisms, including many algae and most fungi, the nuclear envelope does not disassemble during mitosis. this fact raises the possibility that mitotic onset and/or exit might be regulated, in part, by movement of important mitotic proteins into and out of the nucleoplasm. we have used two methods to determine whether tubulin levels in the nucleoplasm are regulated in the fungus aspergillus nidulans. first, we have used benomyl to disassemble microtubules and create a pool of f ...200312802085
evaluation of aspergillus niger as host for virus-like particle production, using the hepatitis b surface antigen as a model.the filamentous fungus aspergillus niger was transformed with the hepatitis b virus s gene encoding the major viral envelope protein under control of the constitutive a. nidulans glyceraldehyde-3-phosphate dehydrogenase ( gpda) promoter. approximately seven copies of the expression cassette were integrated on the genome, resulting in high-level transcription of the s gene. production of the 24-kda s protein and a 48-kda s protein dimer in the membrane-associated protein fraction of the recombina ...200312802503
sex slows down the accumulation of deleterious mutations in the homothallic fungus aspergillus nidulans.coexistence of sexual and asexual reproduction within the same individual is an intriguing problem, especially when it concerns homothallic haplonts, like the fungus aspergillus nidulans. in this fungus asexual and sexual offspring have largely identical genotypes. this genetic model organism is an ideal tool to measure possible fitness effects of sex (compared to asex) resulting from causes other than recombination. in this article we show that slightly deleterious mutations accumulate at a low ...200312807769
adaptation to environmental ph in candida albicans and its relation to pathogenesis.for microorganisms that grow over a wide range of extracellular ph, systems must have evolved to sense and respond appropriately. the human opportunistic pathogen candida albicans colonizes and infects anatomical sites of diverse ph, including the oral and gastro-intestinal tracts and the vaginal cavity. the ability to sense and respond to neutral-alkaline environments is governed by signal transduction pathways, one of which culminates in the activation of the transcription factor, rim101p. the ...200312819929
glycerol dehydrogenase, encoded by gldb is essential for osmotolerance in aspergillus nidulans.we have characterized the aspergillus nidulans gldb gene encoding a nadp+-dependent glycerol dehydrogenase. a basal expression level was observed for gldb, which increased significantly under conditions of hyper-osmotic shock (1 m nacl). growth of strains in which gldb was disrupted was severely reduced on plates containing 1% glucose and 1 m nacl, but these strains were able to grow on plates containing 1 m nacl and 1% glycerol, arabitol, mannitol or erythritol. uptake of these polyols compensa ...200312823816
isolation of the carbon catabolite repressor (crea) gene from the plant-pathogenic fungus cochliobolus carbonum.the crea gene has been implicated in glucose repression in several fungi. the product of this gene, crea, binds to the promoter region of several enzymes and down-regulates gene expression. an ortholog of crea was isolated and characterized from the maize pathogenic fungus, cochliobolus carbonum. the deduced amino acid sequence of the c. carbonum crea gene is very similar to the crea proteins of aspergillus niger, gibberella fujikuroi, sclerotinia sclerotiorum and trichoderma reesei, as well as ...200312825351
[guttural pouch mycosis by emericella nidulans in a horse].a case of guttural pouch mycosis in a horse caused by emericella nidulans is reported for the first time in spain. the high incidence of e. nidulans in this special kind of mycoses is discussed.200212825984
the siderophore system is essential for viability of aspergillus nidulans: functional analysis of two genes encoding l-ornithine n 5-monooxygenase (sida) and a non-ribosomal peptide synthetase (sidc).the filamentous ascomycete a. nidulans produces two major siderophores: it excretes triacetylfusarinine c to capture iron and contains ferricrocin intracellularly. in this study we report the characterization of two siderophore biosynthetic genes, sida encoding l-ornithine n(5)-monooxygenase and sidc encoding a non-ribosomal peptide synthetase respectively. disruption of sidc eliminated synthesis of ferricrocin and deletion of sida completely blocked siderophore biosynthesis. siderophore-deficie ...200312828635
growth inhibition of the filamentous fungus aspergillus nidulans by cadmium: an antioxidant enzyme approach.the heavy metal cadmium is very toxic to biological systems. although its effect on the growth of microorganisms and plants has been investigated, the response of antioxidant enzymes of aspergillus nidulans to cadmium is not well documented. we have studied the effect of cadmium (supplied as cdcl(2)) on catalase (cat), superoxide dismutase (sod) and glutathione reductase (gr). 0.005 mm cdcl(2) had a very slight stimulatory effect on the growth rate of a. nidulans, but at concentrations above 0.0 ...200312833209
re: watts et al. proteins 2002;48:161-168. 200312833536
a blumeria graminis gene family encoding proteins with a c-terminal variable region with homologues in pathogenic a study aimed at characterising, at the molecular level, the obligate biotrophic fungus blumeria graminis f. sp. hordei (bgh), we have identified a novel group of genes, the egh16h genes, and shown that two of these are up-regulated during primary infection of barley leaves. the genes have partial homology to a previously characterised bgh gene family, egh16. egh16 and egh16h are subfamilies of a larger multigene family with presently about 15 members identified in bgh. egh16h has about ten m ...200312853153
histone deacetylases in fungi: novel members, new facts.acetylation is the most prominent modification on core histones that strongly affects nuclear processes such as dna replication, dna repair and transcription. enzymes responsible for the dynamic equilibrium of histone acetylation are histone acetyltransferases (hats) and histone deacetylases (hdacs). in this paper we describe the identification of novel hdacs from the filamentous fungi aspergillus nidulans and the maize pathogen cochliobolus carbonum. two of the enzymes are homologs of saccharom ...200312853613
the cop9 signalosome is an essential regulator of development in the filamentous fungus aspergillus nidulans.the cop9 signalosome (csn) is a conserved multiprotein complex involved in regulation of eukaryotic development. the deduced amino acid sequences of two aspergillus nidulans genes, csnd and csne, show high identities to the fourth and fifth csn subunits of higher eukaryotes. the csnd transcript is abundant during vegetative growth as well as development and the corresponding protein accumulates in the nucleus. strains deleted for either csn gene are viable and show identical mutant phenotypes at ...200312864854
faster genetic identification of medically important aspergilli by using gellan gum as gelling agent in mycological media.using gellan gum as a substitute for agar-agar in a mycological medium and sequencing of the its 1 and 2 regions resulted in an accurate identification of aspergillus fumigatus, aspergillus nidulans, aspergillus terreus and aspergillus ustus within 24 h of subculture.200312867558
monacolin n, a compound resulting from derailment of type i iterative polyketide synthase function en route to lovastatin.a novel compound, monacolin n, has been isolated from fermentation cultures of aspergillus nidulans in which the lovastatin polyketide synthase genes lovb and lovc are heterologously expressed.200312868719
antifungal activity of human polymorphonuclear and mononuclear phagocytes against non-fumigatus aspergillus species.human phagocytic defenses against non-fumigatus aspergilli were compared with those against aspergillus fumigatus. monocyte-derived macrophages exhibited lower phagocytic capacities against non-fumigatus aspergilli, particularly a. nidulans and a. niger, compared with a fumigatus (p < 0.05). non-opsonized hyphae suppressed oxidative burst (as measured by superoxide anion production) of polymorphonuclear leukocytes (pmns). further, these cells responded with less vigorous oxidative burst to serum ...200312870194
identification of a topoisomerase i mutant, scsa1, as an extragenic suppressor of a mutation in scaa(nbs1), the apparent homolog of human nibrin in aspergillus nidulans.the mre11-rad50-nbs1 protein complex has emerged as a central player in the human cellular dna damage response, and recent observations suggest that these proteins are at least partially responsible for the linking of dna damage detection to dna repair and cell cycle checkpoint functions. mutations in scaa(nbs1), which encodes the apparent homolog of human nibrin in aspergillus nidulans, inhibit growth in the presence of the antitopoisomerase i drug camptothecin. this article describes the selec ...200312871905
does the detoxification of penicillin side-chain precursors depend on microsomal monooxygenase and glutathione s-transferase in penicillium chrysogenum?the glutathione (gsh) s-conjugation of 1,2-epoxy-3-(4'-nitrophenoxy)propane was catalysed predominantly by microsomal glutathione s-transferase (mgst) in penicillium chrysogenum. the specific mgst activity unlike the cytosolic gst (cgst) activity increased substantially when the penicillin side-chain precursor phenoxyacetic acid (poa) was included in the culture medium. therefore, a microsomal monooxygenase (causing possible release of epoxide intermediates) and mgst-dependent detoxification pat ...200312872310
the aspergillus nidulans metr gene encodes a bzip protein which activates transcription of sulphur metabolism genes.the identification, isolation and characterization of a new aspergillus nidulans positive-acting gene metr, which encodes a transcriptional activator of sulphur metabolism, is reported. metr mutants are tight auxotrophs requiring methionine or homocysteine for growth. mutations in the metr gene are epistatic to mutations in the negative-acting sulphur regulatory scon genes. the metr coding sequence is interrupted by a single intron of 492 bp which is unusually long for fungi. aspergillus nidulan ...200312890030
metabolic control analysis of xylose catabolism in aspergillus.a kinetic model for xylose catabolism in aspergillus is proposed. from a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. use of the kinetic model allowed metabolic control analysis (mca) of the xylose catabolic pathway to be carried out, and flux control was shown to be dependent on the metabolite levels. due to thermodynamic constraints, flux control may reside at the first step in the pathway, i.e., at the xylose reductase, even when ...200312892473
functional analysis of mutations in the human carnitine/acylcarnitine translocase in aspergillus nidulans.deficiency of the carnitine/acylcarnitine translocase (cact), the most severe disorder of fatty acid beta-oxidation, is usually lethal in both humans and animals, precluding the development of animal models of the disease. in contrast, cact deficiency is conditionally lethal in the fungus aspergillus nidulans, since loss-of-function mutations in acuh, the translocase structural gene, do not prevent growth on carbon sources other than ketogenic compounds, such as fatty acids. here, we describe th ...200312892634
the ph-induced glycosylation of secreted phosphatases is mediated in aspergillus nidulans by the regulatory gene pacc-dependent this communication, we show that the pacc(c)14 mutation drastically reduced the mannose and n-acetylglycosamine content of the paca-encoded acid phosphatase secreted by the fungus aspergillus nidulans when grown at 22 degrees c, ph 5.0, compared to a control strain. the staining after page was not observed for the paca-encoded acid phosphatase, while the pald-encoded pi-repressible alkaline phosphatase had an altered electrophoretic mobility. in addition, the secreted acid phosphatase also ha ...200312892641
molecular cloning of a phospholipase d gene from aspergillus nidulans and characterization of its deletion mutants.we cloned a gene plda encoding a protein containing phospholipase d (pld) motifs from a filamentous fungus aspergillus nidulans. the deduced protein product of plda consists of 833 amino acids and contains four conserved regions of a pld gene family. deletion mutants of plda grew and formed conidia in a normal manner. although pld and transphosphatidylation activities against phosphatidylcholine of the mutant cell extract did not change, the ca(2+)-dependent pld activity against phosphatidyletha ...200312892887
ura- host strains for genetic manipulation and heterologous expression of torulaspora delbrueckii.recently, the industrial and academic interest in the yeast torulaspora delbrueckii has increased notably due to its high resistance to several stresses. this characteristic has made of this organism a very attractive model to study the molecular basis of the stress response in yeast. however, very little is known about the physiology and genetics of this yeast, and the tools for its manipulation have not been developed. here, we have generated ura(-) strains of the baker's yeast t. delbrueckii ...200312892923
global nutritional profiling for mutant and chemical mode-of-action analysis in filamentous fungi.we describe a method for gene function discovery and chemical mode-of-action analysis via nutrient utilization using a high throughput nutritional profiling platform suitable for filamentous microorganisms. we have optimized the growth conditions for each fungal species to produce reproducible optical density growth measurements in microtiter plates. we validated the nutritional profiling platform using a nitrogen source utilization assay to analyze 21 aspergillus nidulans strains with mutations ...200312898394
glucose uptake in germinating aspergillus nidulans conidia: involvement of the crea and sora genes.d-glucose uptake in germinating wild-type aspergillus nidulans conidia is an energy-requiring process mediated by at least two transport systems of differing affinities for glucose: a low-affinity system (k(m) approximately 1.4 mm) and a high-affinity system (k(m) approximately 16 micro m). the low-affinity system is inducible by glucose; the high-affinity system is subject to glucose repression effected by the carbon catabolite repressor crea and is absent in sora3 mutant conidia, which exhibit ...200312904552
mannitol is required for stress tolerance in aspergillus niger conidiospores.d-mannitol is the predominant carbon compound in conidiospores of the filamentous fungus aspergillus niger and makes up 10 to 15% of the dry weight. a number of physiological functions have been ascribed to mannitol, including serving as a reserve carbon source, as an antioxidant, and to store reducing power. in this study, we cloned and characterized the a. niger mpda gene, which encodes mannitol 1-phosphate dehydrogenase (mpd), the first enzyme in the mannitol biosynthesis pathway. the mpda pr ...200312912888
diverged binding specificity of rim101p, the candida albicans ortholog of pacc.the biology of candida albicans, including dimorphism and virulence, is significantly influenced by environmental ph. the response to ambient ph includes the ph-conditional expression of several genes, which is directly or indirectly regulated by rim101p. rim101p is homologous to pacc, a transcription factor that regulates ph-conditional gene expression in aspergillus nidulans. pacc binds 5'-gccarg-3' sequences upstream of ph-responsive genes and either activates or represses transcription. the ...200312912891
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