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photosynthetic fractionation of the stable isotopes of oxygen and carbon.isotope discrimination during photosynthetic exchange of o2 and co2 was measured using enzyme, thylakoid, and whole cell preparations. evolved oxygen from isolated spinach thylakoids was isotopically identical (within analytical error) to its source water. similar results were obtained with anacystis nidulans richter and phaeodactylum tricornutum bohlin cultures purged with helium. for consumptive reactions, discrimination ([delta], where 1 + [delta]/1000 equals the isotope effect, k16/k18 or k1 ...199312231663
disruption of the aspergillus niger argb gene: a tool for transformation.we disrupted the aspergillus niger gene argb, encoding ornithine transcarbamylase. full characterisation of the argb deletion was performed by southern blot analysis, growth tests and by means of mitotic recombination, complementation and transformation. the argb locus was found to be physically removed, thus creating an auxotrophic mutation. the latter can be supplemented by addition of arginine into the culture medium. the argb gene and its disruption do not correlate to the argi13 (formerly a ...200212228812
heterologous expression of the aspergillus nidulans alcr-alca system in aspergillus niger.the inducible and strongly expressed alca gene encoding alcohol dehydrogenase i from aspergillus nidulans was transferred together with the activator gene alcr, in the industrial fungus aspergillus niger. this latter organism does not possess an inducible alc system but has an endogenously constitutive lowly expressed alcohol dehydrogenase activity. the overall induced expression of the alca gene was of the same order in both fungi, as monitored by alca transcription, alcohol dehydrogenase activ ...200212223193
the vea gene activates sexual development in aspergillus nidulans.the previously isolated gene complementing the vea1 mutation was confirmed to be the vea gene. the determined nucleotide sequence of the gene demonstrated that there is an open reading frame (orf) of a 573 amino acid polypeptide. the nucleotide sequence matched some clones of which functions were not assigned yet and the amino acid sequence matched that of neurospora crassa vea-related protein with 61% similarity. the nucleotide sequence of the vea1 mutant gene differed from that of the wild typ ...200212223191
visualization of vacuoles in aspergillus oryzae by expression of cpy-egfp.vacuolar carboxypeptidase y (cpy) from aspergillus nidulans was used to construct a cpy-egfp fusion protein and expressed in a. oryzae to study vacuolar morphology and functions in a. oryzae. while the fluorescence of egfp was barely detectable in a. oryzae expressing cpy-egfp grown under normal conditions at ph 5-6, the increase in ph of the growth medium towards alkalinity restored the fluorescence. in accordance with such an observation, the fluorescence of cpy-egfp fusion protein in cell ext ...200212223187
the nek2 protein kinase: a novel regulator of centrosome structure.regulation of the centrosome, the major microtubule organizing centre in an animal cell, is in large part controlled by cell cycle-dependent protein phosphorylation. along with cyclin dependent kinases, polo kinases and aurora kinases, nima-related kinases are emerging as critical regulators of centrosome structure and function. nek2 is the most closely related vertebrate protein by sequence to the essential mitotic regulator nima of aspergillus nidulans. nek2 is highly enriched at the centrosom ...200212214248
a single fks homologue in yarrowia lipolytica is essential for viability.the synthesis of beta-1,3-glucan, the structural component of the yeast cell wall which gives shape to the cell, occurs at the plasma membrane and is the result of the activity of at least a two-component complex. fks1p is the catalytic subunit directly responsible for the synthesis of beta-1,3-glucan, whilst the second subunit, rho1p, has a gtp-dependent regulatory role. fks1 has been characterized in saccharomyces cerevisiae, where its function is at least partially redundant with that of fks2 ...200212210896
relationship between secondary metabolism and fungal development.filamentous fungi are unique organisms-rivaled only by actinomycetes and plants-in producing a wide range of natural products called secondary metabolites. these compounds are very diverse in structure and perform functions that are not always known. however, most secondary metabolites are produced after the fungus has completed its initial growth phase and is beginning a stage of development represented by the formation of spores. in this review, we describe secondary metabolites produced by fu ...200212208999
dynamic distribution of bimg(pp1) in living hyphae of aspergillus indicates a novel role in septum formation.mutation of bimg, the major protein phosphatase 1 gene in aspergillus nidulans, causes multiple cell cycle and hyphal growth defects that are associated with overphosphorylation of subcellular components. we have used functional translational fusions with the green fluorescent protein (gfp) to show that bimg has at least four discrete locations within growing hyphae. three of these locations, the hyphal tip, the spindle pole body and the nucleus, correlate with previously known requirements for ...200212207691
proteome analysis of aspergillus nidulans reveals proteins associated with the response to the antibiotic concanamycin a, produced by streptomyces species.competition between microbes is common to all ecosystems, but the exact nature of the competition is in most cases unknown. we have previously studied the antagonism between streptomyces halstedii and several fungi at both the organismal and gene expression levels. here we analysed the effect of an antibiotic produced by streptomyces, concanamycin a, on protein levels in the filamentous fungus aspergillus nidulans. two-dimensional gel electrophoresis revealed that 20 proteins either increased or ...200212207217
identification of members of the aspergillus nidulans srea regulon: genes involved in siderophore biosynthesis and utilization.iron is an essential trace element for almost all organisms. however, an excess of this metal within cells can be deleterious on account of catalysis of cell-damaging hydroxyl radicals. therefore, the concentration of iron within cells is tightly regulated and the primary control occurs by regulating its uptake. under conditions of low iron availability, most fungi mobilize extracellular iron by excretion of low-molecular-mass ferric iron chelators, termed siderophores. due to the potential impa ...200212196195
identification of genes involved in terbinafine resistance in aspergillus nidulans.to determine the pattern and the genetic basis of resistance to terbinafine, a drug extensively used for the treatment of fungal infections in humans.200212180946
saka map kinase is involved in stress signal transduction, sexual development and spore viability in aspergillus nidulans.in eukaryotic cells, environmental stress signals are transmitted by evolutionarily conserved mapks, such as hog1 in the budding yeast saccharomyces cerevisiae, spc1 in the fission yeast schizosaccharomyces pombe and p38/jnk in mammalian cells. here, we report the identification of the aspergillus nidulans saka gene, which encodes a member of the stress mapk family. the saka gene is able to complement the s. pombe spc1- defects in both osmo-regulation and cell cycle progression. moreover, saka m ...200212180932
a novel method used to delete a new aspergillus fumigatus abc transporter-encoding gene.aspergillus fumigatus is an important opportunistic human pathogenic fungus. in severely immunocompromised patients, the fungus causes life-threatening diseases, such as pneumonia and invasive aspergillosis. in order to obtain a better understanding of the key elements involved in a. fumigatus virulence and for identifying possible drug targets, it is essential to be able to generate gene-deletion strains. until recently, the molecular techniques available did not provide a rapid method for gene ...200212172968
chsz, a gene for a novel class of chitin synthase from aspergillus oryzae.we cloned and characterized a novel aspergillus oryzae chitin synthase gene, chsz, encoding a polypeptide containing a new myosin motor-like domain in its n-terminal half. alignment analysis revealed that chsz was less homologous to known class v enzymes, except for its probable chitin synthase conserved region in the c-terminal half. we also found a chsy gene and found that chsy showed higher similarity to the class v enzymes than did chsz. phylogenetic analysis clearly demonstrated that the a. ...200212172967
the absence of molybdenum cofactor sulfuration is the primary cause of the flacca phenotype in tomato plants.the molybdenum cofactor (moco)-containing enzymes aldehyde oxidase (ao; ec 1.2.3.1) and xanthine dehydrogenase (xdh; ec 1.2.1.37) require for activity a sulfuration step that inserts a terminal sulfur ligand into the moco. the tomato flacca mutation was originally isolated as a wilty phenotype due to a lack of abscisic acid (aba) that is related to simultaneous loss of ao and xdh activities. an expressed sequence tag candidate from tomato was selected on the basis of homology to sulfurases from ...200212164810
disruption of the glucosylceramide biosynthetic pathway in aspergillus nidulans and aspergillus fumigatus by inhibitors of udp-glc:ceramide glucosyltransferase strongly affects spore germination, cell cycle, and hyphal growth.the opportunistic mycopathogen aspergillus fumigatus expresses both glucosylceramide and galactosylceramide (glccer and galcer), but their functional significance in aspergillus species is unknown. we here identified and characterized a glccer from aspergillus nidulans, a non-pathogenic model fungus. involvement of glccer in fungal development was tested on both species using a family of compounds known to inhibit glccer synthase in mammals. two analogs, d-threo-1-phenyl-2-palmitoyl-3-pyrrolidin ...200212163162
comparison of the etest and the sensititre colorimetric methods with the nccls proposed standard for antifungal susceptibility testing of aspergillus species.the susceptibilities of 25 clinical isolates of aspergillus fumigatus, a. flavus, a. terreus, a. nidulans, and a. ustus to itraconazole and amphotericin b were determined by an agar diffusion-dilution method (the etest method) and a colorimetric broth microdilution method (the sensititre method); and the results were compared with those obtained by the nccls proposed standard m-38p method for antifungal susceptibility testing of filamentous fungi. various mic endpoints for the three methods were ...200212149345
properties and application of a partially purified alkaline xylanase from an alkalophilic fungus aspergillus nidulans kk-99.an alkalophilic aspergillus nidulans kk-99 produced an alkaline, thermostable xylanase (40 iu/ml) in a basal medium supplemented with wheat bran (2% w/v) and kno3 (at 0.15% n) ph 10.0 and 37 degrees c. the partially purified xylanase was optimally active at ph 8.0 and 55 degrees c. the xylanase was stable in a broad ph range of 4.0-9.5 for 1 h at 55 degrees c, retaining more than 80% of its activity. the enzyme exhibited greater binding affinity for xylan from hardwood than from softwood. the xy ...200212146641
improving extracellular production of food-use enzymes from aspergillus nidulans.filamentous fungi, and particularly those of the genus aspergillus, are major producers of enzymatic activities that have important applications in the food and beverage industries. prior to the availability of transformation systems improvement of industrial production strains was largely restricted to the strategy of mutagenesis, screening and selection. aspergillus nidulans is a genetically amenable filamentous fungus the ease of handling and analysis of which has led to its use as a model sy ...200212142142
functional characterization of 4'-phosphopantetheinyl transferase genes of bacterial and fungal origin by complementation of saccharomyces cerevisiae lys5.lysine biosynthesis in yeast requires the posttranslational conversion of the alpha-aminoadipate semialdehyde reductase lys2 by the 4'-phosphopantetheinyl transferase (pptase) lys5 from the inactive apo-form into the catalytically active holo-form. in this reaction, the peptidyl carrier domain of lys2 is modified at a conserved serine residue side chain with the 4'-phosphopantetheine moiety derived from coenzyme a. we have deleted the lys5 gene in saccharomyces cerevisiae to investigate the subs ...200212127488
vincristine induces somatic segregation, via mitotic crossing-over, in diploid cells of aspergillus nidulans.vincristine is an alkaloid widely used as an antineoplastic agent. in eukaryotic cells the drug causes blockage in the g2 phase of the cell cycle and an increase in the frequency of sister chromatid exchanges. due to the fact that germinating aspergillus nidulans cells spend most of their cycle in g2 phase, they provide an excellent system for the study of mitotic crossing-over. taking into account that mitotic crossing-over occurs during g2 period, the evaluation of recombinagenic and aneugenic ...200212125202
the aspergillus nidulans cyclin pcla accumulates in the nucleus and interacts with the central cell cycle regulator nimx(cdc2).the filamentous fungus aspergillus nidulans reproduces asexually through conidiospores, which are continuously generated at morphologically differentiated structures, the conidiophores. in contrast to vegetative, multinucleate cells, spore formation requires a strict coordination of mitosis and cytokinesis. it was shown recently that the key regulator of the cell cycle in a. nidulans nimx(cdc2) and a g(1)/s cyclin, pcla, are transcriptionally upregulated during development. here we show that pcl ...200212123821
gamma-tubulin. 200212123586
the soybean gmn6l gene encodes a late nodulin expressed in the infected zone of nitrogen-fixing nodules.previously, we determined the n-terminal amino acid sequences of a number of putative peribacteroid membrane proteins from soybean. here, we report the cloning of a gene, gmn6l, that encodes one of these proteins. the protein encoded by gmn6l is similar in sequence to mtn6, an early nodulin expressed in medicago truncatula roots in response to infection by sinorhizobium meliloti. the gmn6l gene was strongly expressed in mature nodules but not in other plant organs. gmn6l protein was first detect ...200212118878
ethanol vapor is an efficient inducer of the alc gene expression system in model and crop plant species.we have demonstrated that low concentrations of ethanol vapor efficiently induce the alc gene expression system in tobacco (nicotiana tabacum cv samsun nn), potato (solanum tuberosum cv solara), and oilseed rape (brassica napus cv westar). for many situations, this may be the preferred method of induction because it avoids direct application of comparatively high concentrations of an ethanol solution. although induction was seen with less than 0.4 microm ethanol vapor, maximal induction of the c ...200212114549
kinetic analysis of the interaction between the quta and qutr transcription-regulating proteins.the qutr protein is a multidomain repressor protein that interacts with the quta activator protein. both proteins are active in the signal transduction pathway that regulates transcription of the quinic acid utilization (qut) gene cluster of the microbial eukaryote aspergillus nidulans. in the presence of quinate, production of mrna from the eight genes of the qut pathway is stimulated by the quta activator protein. the qutr protein plays a key role in signal recognition and transduction, and a ...200212112685
a regulator gene for acetate utilisation from neurospora crassa.the neurospora crassa homologue of the aspergillus nidulans regulatory gene facb has been cloned. the gene encodes a putative transcriptional activator of 865 amino acids that contains a dna-binding domain with a zn(ii)(2)cys(6) binuclear cluster, a linker region and a leucine zipper-like heptad repeat. two internal amino acid sequences are identical to peptide sequences determined from proteolytic fragments of a dna-binding protein complex specific for genes involved in acetate utilisation and ...200212111557
functional expression and cellular localization of cercosporin-resistance proteins fused with the gfp in cercospora nicotianae.the cercospora nicotianae pdx1 and crg1 genes were previously identified as genes required for resistance to the singlet oxygen ((1)o(2))-generating toxin cercosporin. the pdx1 gene has subsequently been shown to be required for pyridoxine biosynthesis, but both the precise biochemical function of the pdx1 protein and the function of the crg1 protein remain undefined, as both sequences lack defined enzymatic domains or cofactor-binding sites. the gfp gene encoding green fluorescent protein was t ...200212111097
carbon catabolite repression in the regulation of beta-galactosidase activity in aspergillus nidulans. 200212109156
cloning and characterization of a gene (avaa) from aspergillus nidulans encoding a small gtpase involved in vacuolar biogenesis.several genes that play roles in vacuolar biogenesis and targeting of proteins to vacuoles have been characterized in saccharomyces cerevisiae. although the vacuole is one of the most prominent compartments, little is known about molecular mechanism of vacuolar biogenesis in filamentous fungi. vam4/ypt7p, a small gtpase of the rab/ypt family in s. cerevisiae, plays a vital role in homotypic vacuole fusion. we describe the isolation of the avaa gene from aspergillus nidulans as a homologue of the ...200212095681
transcriptional control of nitric oxide reductase gene (cyp55) in the fungal denitrifier fusarium oxysporum.fungal denitrification is a dissimilating metabolic mechanism for nitrate and was first described in fusarium oxysporum. here we investigated regulatory systems of expression of cyp55, which encodes cytochrome p450 (p450nor) and is essential for the fungal denitrification. promoter-reporter analysis of f. oxysporum cyp55 using escherichia coli beta-galactosidase showed that the region between nucleotides -526 and -515 was critical for induction by nitrate. it contained a nucleotide sequence simi ...200212092813
isogamous, hermaphroditic inheritance of mitochondrion-encoded resistance to qo inhibitor fungicides in blumeria graminis f. sp. tritici.a mutation of glycine to alanine at position 143 in the mitochondrial cytochrome b amino acid sequence of blumeria graminis f. sp. tritici cosegregated with the qoi-resistant phenotype in a ratio of 1:1 in a cross between a sensitive and a resistant isolate. this mutation was used as a mitochondrial marker to determine whether mitochondrial inheritance in b. graminis was anisogamous, as in heterothallic neurospora sp., or isogamous and hermaphroditic, as in aspergillus nidulans. segregation of m ...200212081463
the importance of hydrophobicity and electrophilicity descriptors in mechanistically-based qsars for toxicological endpoints.quantitative structure-activity relationship (qsar) analysis of four toxicological data sets is described. the toxicological data include three data sets retrieved from the literature (the toxic and metabolic effects of 23 aliphatic alcohols on the perfused rat liver; the toxicity of 21 pyridines to mice; the lethality of 55 halogenated hydrocarbons to the mould aspergillus nidulans). in addition, the toxicity of 13 mono- and di-substituted nitrobenzenes in a 15 min assay using the alga chlorell ...200212074385
mutational analysis of the gephyrin-related molybdenum cofactor biosynthetic gene cnxe from the lower eukaryote aspergillus nidulans.we report the identification of a number of mutations that result in amino acid replacements (and their phenotypic characterization) in either the moga-like domain or domains 2 and 3 of the moea-like region of the aspergillus nidulans cnxe gene. these domains are functionally required since mutations that result in amino acid substitutions in any one domain lead to the loss or to a substantial reduction in all three identified molybdoenzyme activities (i.e., nitrate reductase, xanthine dehydroge ...200212072459
yeasts of the genus candida are the dominant cause of onychomycosis in libyan women but not men: results of a 2-year surveillance study.the reported frequency of recovery of fungi from infected nails varies according to the geographical area.200212072073
invasive aspergillus infections in hematologic malignancy patients.the incidence of invasive aspergillus (ia) infections in patients with hematologic malignancies continues to increase. the most common species include aspergillus fumigatus (approximately 90% of cases), a. flavus, a. niger, a. terreus, and a. nidulans. most infections involve the pulmonary parenchyma, though systemic dissemination of the fungus from a primary pulmonary focus or the paranasal sinuses after hyphal invasion into blood vessels is frequent. early diagnosis and initiation of appropria ...200212070828
schizosaccharomyces pombe nima-related kinase, fin1, regulates spindle formation and an affinity of polo for the spb.the aspergillus nidulans protein kinase nima regulates mitotic commitment, while the human and xenopus equivalents influence centrosome function. two recessive, temperature-sensitive mutations in the schizosaccharomyces pombe nima homologue, fin1, blocked spindle formation at 37 degrees c. one of the two spindle pole bodies (spbs) failed to nucleate microtubules. this phenotype was reduced by accelerating mitotic commitment through genetic inhibition of wee1 or activation of either cdc25 or cdc2 ...200212065422
molecular cloning and characterization of the human nima-related protein kinase 3 gene (nek3).neks (nima-related kinases) are a group of protein kinases sharing high amino acid sequence identities with nima (never in mitosis gene a) which control mitosis in aspergillus nidulans. we have cloned a cdna for human nek3, a novel human gene structurally related to nima, by rt-pcr. its open reading frame encodes a protein of 489 amino acid residues with the calculated molecular mass of 56.0 kda and a predicted pi of 6.58. phylogenetic analysis suggests that mouse and human nek3s constitute a su ...200112063396
yeast npi3/bro1 is involved in ubiquitin-dependent control of permease trafficking.the membrane traffic and stability of the general amino acid permease gap1 of saccharomyces cerevisiae are under nitrogen control. addition of a preferential nitrogen source such as ammonium to cells growing on a poor nitrogen source induces internalization of the permease and its subsequent degradation in the vacuole. this down-regulation requires ubiquitination of gap1 through a process involving ubiquitin ligase npi1/rsp5, ubiquitin hydrolase npi2/doa4, and bul1/2, two npi1/rsp5 interacting p ...200212062418
isolation of fluconazole-tolerant micromycetes onto different cultivation media.on studying the dependence of quality and/or quantity of environmental fluconazole-tolerant micromycetes on culture medium in vitro, the highest number of isolates was obtained in sabouraud agar (sa) without fluconazole (59 cfu/mg of soil sample at 25 degrees c and 31 cfu/mg at 37 degrees c). in the case of sa, fluconazole inhibited the growth of micromycetes to 83%. significant differences were found between the average concentration of cfu/mg for six cultivation media without and with fluconaz ...200212058387
identification and characterization of nek6 protein kinase, a potential human homolog of nima histone h3 kinase.in aspergillus nidulans, the kinase activity of nima (never in mitosis, gene a) is critical for the initiation of mitosis. nima regulates mitotic chromatin condensation through phosphorylation of histone h3 at serine 10. in the present study, we identified human nek6 (hnek6), a member of the mammalian nima-related kinases. the predicted hnek6 protein is comprised of 338 amino acids. northern blot analysis revealed that hnek6 transcripts are ubiquitously expressed with the highest expression foun ...200212054534
proteomics of the eukaryotic transcription machinery: identification of proteins associated with components of yeast tfiid by multidimensional mass spectrometry.the general transcription factor tfiid is a multisubunit complex of tata-binding protein (tbp) and 14 distinct tbp-associated factors (tafs). although tfiid constituents are required for transcription initiation of most mrna encoding genes, the mechanism of tfiid action remains unclear. to gain insight into tfiid function, we sought to generate a proteomic catalogue of proteins specifically interacting with tfiid subunits. toward this end, tfiid was systematically immunopurified by using polyclo ...200212052880
mutation and functional analysis of the aspergillus nidulans ammonium permease meaa and evidence for interaction with itself and mepa.the movement of ammonium across biological membranes is mediated in both prokaryotic and eukaryotic systems by ammonium transport proteins which constitute a family of related sequences (called the amt/mep family). interestingly, recent evidence suggests that human and mouse rhesus proteins which display significant relatedness to amt/mep sequences may function as ammonium transporters. to add to the functional understanding of ammonium transport proteins, the sequence changes in 37 loss-of-func ...200212051893
camp and ras signalling independently control spore germination in the filamentous fungus aspergillus nidulans.the role of camp signalling during germination of asexual spores (conidia) of the filamentous fungus aspergillus nidulans was investigated. a. nidulans strains defective for adenylate cyclase (cyaa) or for the functionally overlapping camp-dependent protein kinase (pkaa) and newly characterized scha protein kinase, homologous to saccharomyces cerevisiae sch9, show altered trehalose mobilization and kinetics of germ tube outgrowth, in addition to other defects in colony formation. camp-dependent ...200212046590
a gene from aspergillus nidulans with similarity to ure2 of saccharomyces cerevisiae encodes a glutathione s-transferase which contributes to heavy metal and xenobiotic resistance.aspergillus nidulans is a saprophytic ascomycete that utilizes a wide variety of nitrogen sources. we identified a sequence from a. nidulans similar to the glutathione s-transferase-like nitrogen regulatory domain of saccharomyces cerevisiae ure2. cloning and sequencing of the gene, designated gsta, revealed it to be more similar to ure2 than the s. cerevisiae glutathione s-transferases. however, creation and analysis of a gsta deletion mutant revealed that the gene does not participate in nitro ...200212039735
isomaltulose synthase from klebsiella sp. strain lx3: gene cloning and characterization and engineering of thermostability.the gene (pali) encoding isomaltulose synthase (pali) from a soil bacterial isolate, klebsiella sp. strain lx3, was cloned and characterized. pali converts sucrose into isomaltulose, trehalulose, and trace amounts of glucose and fructose. sequence domain analysis showed that pali contains an alpha-amylase domain and (beta/alpha)(8)-barrel structures, suggesting that it belongs to the alpha-amylase family. sequence alignment indicated that the five amino acid residues of catalytic importance in a ...200212039719
structurally and functionally conserved domains in the diverse hydrophilic carboxy-terminal halves of various yeast and fungal na+/h+ antiporters (nha1p).genes encoding the na(+)/h(+) antiporter (nha1p) from candida tropicalis (c.t.), hansenula anomala (h.a.) (also named pichia anomala), and aspergillus nidulans (a.n.) were cloned, and the nucleotide sequences were determined. the deduced primary sequences revealed highly conserved hydrophobic regions and rather diverse hydrophilic regions. among the seven known nha1p sequences, schizosaccharomyces pombe (s.p.) nha1p is exceptional in lacking the hydrophilic region. within the diverse hydrophilic ...200212038978
e-test method for testing susceptibilities of aspergillus spp. to the new triazoles voriconazole and posaconazole and to established antifungal agents: comparison with nccls broth microdilution method.nccls document m38-p describes standard parameters for testing the fungistatic activities (mics) of established agents against filamentous fungi (molds). this study evaluated the in vitro susceptibilities of 15 aspergillus flavus isolates, 62 a. fumigatus isolates, and 10 isolates each of a. niger, a. nidulans, and a. terreus to voriconazole, posaconazole, itraconazole, and amphotericin b by the e-test and nccls m38-p microdilution methods. the agreement (within 3 dilutions) between methods for ...200212037072
isolation of genes encoding novel transcription factors which interact with the hap complex from aspergillus species.the saccharomyces cerevisiae ccaat-binding factor is composed of four subunits hap2p, hap3p, hap4p and hap5p. three subunits, hap2/3/5p, are required for dna-binding and hap4p is involved in transcriptional activation. although homologues of hap2/3/5p (in the case of aspergillus nidulans; hapb/c/e, respectively) were found in many eukaryotes, no hap4p homologues have been found except for the other yeast, kluyveromyces lactis. with the lexa-hap2, -hapb, -hapc, or -hape fusion gene, we evaluated ...200212031499
promoter elements in the aflatoxin pathway polyketide synthase gene.pksa catalyzes the formation of the polyketide backbone necessary for aflatoxin biosynthesis. based on reporter assays and sequence comparisons of the nor1-pksa intergenic region in different aflatoxin-producing aspergillus species, cis-acting elements for the aflatoxin pathway-specific regulatory protein, aflr, and the global-acting regulatory proteins brla and pacc are involved in pksa promoter activity.200212031498
components of the saga histone acetyltransferase complex are required for repressed transcription of arg1 in rich medium.transcriptional regulation of the saccharomyces cerevisiae arg1 gene is controlled by positive and negative elements. the transactivator gcn4p is required for activation in minimal medium, while arginine repression requires the argr/mcm1 regulatory complex, which binds to two upstream arginine control elements. we have found that the coordinated regulation of arg1 requires components of the saga chromatin-remodeling complex. using gcn5 deletion strains and a gcn5 protein carrying the e173q mutat ...200212024017
characterization of the aspergillus nidulans 14-3-3 homologue, arta.the 14-3-3 family of proteins function as small adaptors that facilitate a diverse array of cellular processes by mediating specific protein interactions. one such process is the dna damage checkpoint, where these proteins prevent inappropriate activation of cyclin-dependent kinases. the filamentous fungus aspergillus nidulans possesses a highly conserved 14-3-3 homologue (arta) that may function in an analogous manner to prevent septum formation. however, instead of blocking septation, over-exp ...200212023078
transformation system of beauveria bassiana and metarhizium anisopliae using nitrate reductase gene of aspergillus nidulans.an heterologous transformation system for entomopathogenic fungi b. bassiana and m. anisopliae was developed based on the use of a. nidulans nitrate reductase gene (niad). b. bassiana and m. anisopliae niad stable mutants were selected by treatment of protoplast with ethane methane sulphonate (ems) and regenerated on chlorate medium. the cloned gene was capable of transforming b. bassiana and m. anisopliae at a frequency of 5.8 to 20 transformants per microg of dna. most of them were mitotically ...200112019757
method for measuring postantifungal effect in aspergillus species.an in vitro method for determination of postantifungal effect (pafe) in molds was developed by using three isolates each of aspergillus fumigatus, a. flavus, a. terreus, a. nidulans, and a. ustus. mics of amphotericin b and itraconazole were determined by using national committee for clinical laboratory standards guidelines (m38-p). the inoculum was prepared in rpmi 1640 broth buffered with mops (morpholinepropanesulfonic acid) at ph 7.0, and conidia were exposed to amphotericin b and itraconazo ...200212019115
the distinctiveness of atp:citrate lyase from aspergillus nidulans.atp:citrate lyase (acl), an important enzyme in lipid synthesis, has been purified from aspergillus nidulans to a specific activity of 19.6 micromol min(-1) mg(-1), almost twice that of any other purified acl and shown to be distinct from any previously purified acl. the enzyme is a 371+/-31 kda hexamer of 3 alpha, 3 beta proteins, unlike the 4 alpha tetramer found in rats or yeasts. the molecular weights of the alpha and beta protein subunits were determined by sds-page to be 70 and 55 kda. acl ...200212009400
transformation of aspergillus sp. and trichoderma reesei using the pyrithiamine resistance gene (ptra) of aspergillus oryzae.a pyrithiamine (pt) resistance gene (ptra) was cloned from a pt resistant mutant of aspergillus oryzae and was useful as a dominant selectable marker for transformation of all a. oryzae wild type strain as well as a. nidulans. for further study, we examined whether or not ptra could be used as the transformation marker in other species of filamentous fungi. two types of plasmid, which contain ptra as a selectable marker, were constructed, and the transformation experiments were done with them. o ...200211999416
refined molecular hinge between allosteric and catalytic domain determines allosteric regulation and stability of fungal chorismate mutase.the yeast chorismate mutase is regulated by tyrosine as feedback inhibitor and tryptophan as crosspathway activator. the monomer consists of a catalytic and a regulatory domain covalently linked by the loop l220s (212-226), which functions as a molecular hinge. two monomers form the active dimeric enzyme stabilized by hydrophobic interactions in the vicinity of loop l220s. the role of loop l220s and its environment for enzyme regulation, dimerization, and stability was analyzed. substitution of ...200211997452
a basic helix-loop-helix protein with similarity to the fungal morphological regulators, phd1p, efg1p and stua, controls conidiation but not dimorphic growth in penicillium marneffei.members of the apses protein group are basic helix-loop-helix (bhlh) proteins that regulate processes such as mating, asexual sporulation and dimorphic growth in fungi. penicillium marneffei is a human pathogen and is the only member of its genus to display a dimorphic growth transition. at 25 degrees c, p. marneffei grows with a filamentous morphology and produces asexual spores from multicellular con-idiophores. at 37 degrees c, the filamentous morphology is replaced by yeast cells that reprod ...200211994146
a novel mechanism for protein-assisted group i intron splicing.previously it was shown that the aspergillus nidulans (a.n.) mitochondrial cob intron maturase, i-anii, facilitates splicing of the cob intron in vitro. in this study, we apply kinetic analysis of binding and splicing along with rna deletion analysis to gain insight into the mechanism of i-anii facilitated splicing. our results are consistent with i-anii and a.n. cob pre-rna forming a specific but labile encounter complex that is resolved into the native, splicing-competent complex. significantl ...200211991637
repression of chsb expression reveals the functional importance of class iv chitin synthase gene chsd in hyphal growth and conidiation of aspergillus nidulans.the functions of two previously identified chitin synthase genes in aspergillus nidulans, chsb and chsd, were analysed. first, a conditional chsb mutant was constructed in which the expression of chsb is under the control of a repressible promoter, the alca promoter, of a. nidulans. under repressing conditions, the mutant grew slowly and produced highly branched hyphae, supporting the idea that chsb is involved in normal hyphal growth. the involvement of chsb in conidiation was also demonstrated ...200211988507
characteristics of physiological inducers of the ethanol utilization (alc) pathway in aspergillus nidulans.the ethanol utilization (alc) pathway in aspergillus nidulans is one of the strongest expressed gene systems in filamentous fungi. the pathway-specific activator alcr requires the presence of an inducing compound to activate transcription of genes under its control. we have demonstrated recently that acetaldehyde is the sole physiological inducer of ethanol catabolism. in the present study we show that compounds with catabolism related to that of ethanol, i.e. primary alcohols, primary monoamine ...200211988072
gal80 confers specificity on hat complex interactions with activators.several yeast transcription activators have been shown to interact with and recruit histone acetyltransferase complexes to promoters in chromatin. the promiscuity of activator/hat interactions suggests that additional factors temporally regulate these interactions in response to signaling pathways. in this study, we demonstrate that the negative regulator, gal80, blocks interactions between the saga and nua4 hat complexes and the gal4 activator. by contrast, gal80 did not inhibit saga and nua4 i ...200211986320
chiral discrimination by hplc and ce and antifungal activity of racemic fenticonazole and its enantiomers.fenticonazole is a chiral antifungal agent, used in therapy as the racemic mixture. the investigation on the chirality of fenticonazole is reported in this study. rac-fenticonazole was resolved by hplc and by capillary electrophoresis (ce). the chiral stationary phase (csp), used in hplc, was daicel od-h, a commercial phase, which allowed the separate collection of the two enantiomers. the chiral selectors used for ce were some cyclodextrin derivatives. the analysis time required from ce was abo ...200211984761
cloning of a prolidase gene from aspergillus nidulans and characterisation of its product.using est sequence information available from the filamentous fungus aspergillus nidulans as a starting point, we have cloned the prolidase-encoding gene, designated pepp. introduction of multiple copies of this gene into the a. nidulansgenome leads to overexpression of an intracellular prolidase activity. prolidase was subsequently purified and characterised from an overexpressing strain. the enzyme activity is dependent on manganese as a cofactor, is specific for dipeptides and hydrolyses only ...200211976965
a novel abc transporter gene, pmr5, is involved in multidrug resistance in the phytopathogenic fungus penicillium digitatum.we have cloned a novel abc transporter gene pmr5 from the phytopathogenic fungus penicillium digitatum by rt-pcr using degenerate primers. the deduced amino acid sequence of pmr5 showed 37% identity to pmr1 from the same fungus, 71% identity to atrb from aspergillus nidulans, and 65% identity to bcatrb from botrytis cinerea. disruption mutants for pmr5 were generated in two independent p. digitatum strains and their phenotypes were characterized. these mutants displayed increased sensitivity to ...200211976961
prna, a zn2cys6 activator with a unique dna recognition mode, requires inducer for in vivo binding.the prna transcriptional activator of aspergillus nidulans binds as a dimer to ccgg-n-ccgg inverted repeats and to ccgg-6/7n-ccgg direct repeats. the binding specificity of the prna zn cluster differs from that of the gal4p/ppr1p/uay/put3p group of proteins. chimeras with uay, a protein that strictly recognizes a cgg-6n-ccg motif, show that the recognition of the direct repeats necessitates the prna dimerization and linker elements, but the recognition of the ccgg-n-ccgg inverted repeats depends ...200211972793
nitrate and the gata factor area are necessary for in vivo binding of nira, the pathway-specific transcriptional activator of aspergillus nidulans.in aspergillus nidulans, the genes coding for nitrate reductase (niad) and nitrite reductase (niia), are transcribed divergently from a common promoter region of 1200 basepairs. we have previously characterized the relevant cis-acting elements for the two synergistically acting transcriptional activators nira and area. we have further shown that area is constitutively bound to a central cluster of four gata sites, and is involved in opening the chromatin structure over the promoter region thus m ...200211972792
cytoplasmic dynein intermediate chain and heavy chain are dependent upon each other for microtubule end localization in aspergillus nidulans.the multisubunit microtubule motor, cytoplasmic dynein, targets to various subcellular locations in eukaryotic cells for various functions. the cytoplasmic dynein heavy chain (hc) contains the microtubule binding and atp binding sites for motor function, whereas the intermediate chain (ic) is implicated in the in vivo targeting of the hc. concerning any targeting event, it is not known whether the ic has to form a complex with the hc for targeting or whether the ic can target to a site independe ...200211972777
aspergillus nidulans sod(vi)c1 mutation causes defects in cell wall biogenesis and protein secretion.growth at the restrictive temperature (42 degrees c) of aspergillus nidulans b120, carrying the conditional-lethal mutation sod(vi)c1, was partially improved by the addition of 1.0 m sorbitol to the medium. the mutant grown at 42 degrees c, with osmotic stabilizer, showed abnormal hyphal morphology, a decrease in beta-1,3-glucan synthase activity as well as cell wall sugar content, but an increase in chitin synthase activity and n-acetyl-glucosamine content. the mutation also affected the secret ...200211959445
interactions defining the specificity between fungal xylanases and the xylanase-inhibiting protein xip-i from wheat.we previously reported on the xylanase-inhibiting protein i (xip-i) from wheat [mclauchlan, garcia-conesa, williamson, roza, ravestein and maat (1999), biochem. j. 338, 441-446]. in the present study, we show that xip-i inhibits family-10 and -11 fungal xylanases. the k(i) values for fungal xylanases ranged from 3.4 to 610 nm, but bacterial family-10 and -11 xylanases were not inhibited. unlike many glycosidase inhibitors, xip-i was not a slow-binding inhibitor of the aspergillus niger xylanase. ...200211955286
the role of isocitrate lyase in aspergillus nidulans. 197011947479
differential transcription of t(4)-dna by dna-dependent rna-polymerase of e. coli and a. nidulans. 196911946973
mutants of aspergillus nidulans lacking pyruvate carboxylase. 197211946370
mutants of aspergillus nidulans lacking malate synthase. 197111945599
immunological differences between inducible and constitutive xanthine dehydrogenases in aspergillus nidulans. 197011945540
isolation and characterization of the mating-type idiomorphs from the wheat septoria leaf blotch fungus mycosphaerella graminicola.both mating-type loci from the wheat septoria leaf blotch pathogen mycosphaerella graminicola have been cloned and sequenced. the mat1-2 gene was identified by screening a genomic library from the mat1-2 isolate ipo94269 with a heterologous probe from tapesia yallundae. the mat1-2 idiomorph is 2772 bp and contains a single gene encoding a putative high-mobility-group protein of 394 amino acids. the opposite idiomorph was obtained from isolate ipo323, which has the complementary mating type, by l ...200211929216
the dna damage response in filamentous fungi.the mechanisms used by fungal cells to repair dna damage have been subjects of intensive investigation for almost 50 years. as a result, the model yeasts schizosaccharomyces pombe and saccharomyces cerevisiae have led the way in yielding critical insights into the nature of the dna damage response. at the same time, largely through the efforts of etta kafer, hirokazu inoue, and colleagues, a substantial collection of aspergillus nidulans and neurospora crassa dna repair mutants has been identifi ...200211929209
france. biologist wins battle over bureaucratic fungus. 200211923508
marker construction and cloning of a cut1-like sequence with ars activity in the fission yeast schizosaccharomyces japonicus.the dimorphic fission yeast schizosaccharomyces japonicus has proved to be an excellent experimental model for the investigation of the eukaryotic cell. here we show that it has a haplontic life cycle, in which the diploid phase is confined to the zygote. to make it amenable to genetic and molecular analysis, we generated genetic markers and cloned a genomic sequence which acts as ars when integrated into a plasmid. diploids suitable for testing complementation and recombination between markers ...200211921097
the fle1 gene encoding a c2h2 zinc finger protein co-ordinates male and female sexual differentiation in podospora anserina.the flexuosa (fle1-1) mutant, isolated in podospora anserina, displays vegetative defects and two antagonistic sexual phenotypes: it produces several 1000-fold fewer microconidia (male gametes) than the wild-type strain and, conversely, more abundant protoperithecia (female organs). cloning and sequencing of the fle1 gene and of cdna identified an open reading frame encoding a 382-amino-acid polypeptide with two c2h2 zinc finger motifs. the predicted fle1 protein shares 46% identity with the flb ...200211918811
the wd40-repeat protein crec interacts with and stabilizes the deubiquitinating enzyme creb in vivo in aspergillus nidulans.genetic dissection of carbon catabolite repression in aspergillus nidulans has identified two genes, creb and crec, which, when mutated, affect expression of many genes in both carbon catabolite repressing and derepressing conditions. the creb gene encodes a functional deubiquitinating enzyme and the crec gene encodes a protein that contains five wd40 repeat motifs, and a proline-rich region. these findings have allowed the in vivo molecular analysis of a cellular switch involving deubiquitinati ...200211918805
osmotic stress-coupled maintenance of polar growth in aspergillus nidulans.free-living cells monitor extracellular 'osmotic strength' and respond metabolically to offset unfavourable osmotic intracellular solute concentrations. here, we report the reconstruction of the aspergillus nidulans salt stress-controlling map kinase pathway, based on homology analysis with known yeast genes. in a. nidulans, salt stress hog genes, such as pbsa, hoga, ptpa and msna, are upregulated when exposed to high concentrations of salt and, in a hoga deletion mutant (sik1), the accumulation ...200211918796
eglc, a new endoglucanase from aspergillus niger with major activity towards xyloglucan.a novel gene, eglc, encoding an endoglucanase, was cloned from aspergillus niger. transcription of eglc is regulated by xlnr, a transcriptional activator that controls the degradation of polysaccharides in plant cell walls. eglc is an 858-amino-acid protein and contains a conserved c-terminal cellulose-binding domain. eglc can be classified in glycoside hydrolase family 74. no homology to any of the endoglucanases from trichoderma reesei was found. in the plant cell wall xyloglucan is closely li ...200211916668
cloning of aspergillus fumigatus histidine kinase gene fragment and its expression during invasive infection.it was demonstrated recently that three histidine kinases genes in candida albicans contributed to virulence, indicating the importance of signaling pathways regulated by histidine kinases. in the present study, using a set of degenerate primers, rt-pcr was performed with cdna of a. fumigatus as a template. pcr products were cloned and sequenced. after blast analysis, it was found that one fragment (named as afhk1), 305 bp, was highly homologous to the two-component histidine kinase tesa gene of ...200211913767
the regulation of nitrate and ammonium transport systems in plants.inorganic nitrogen concentrations in soil solutions vary across several orders of magnitude among different soils and as a result of seasonal changes. in order to respond to this heterogeneity, plants have evolved mechanisms to regulate and influx. in addition, efflux analysis using (13)n has revealed that there is a co-ordinated regulation of all component fluxes within the root, including biochemical fluxes. physiological studies have demonstrated the presence of two high-affinity transporter ...200211912228
the mitochondnal genome of aspergillus nidulans contains reading frames homologous to the human urfs 1 and 4.a 2830-bp segment of the mitochondrial genome of the fungus aspergillus nidulans was sequenced and shown to contain two unidentified reading frames (urfs). these reading frames are 352 and 488 codons in length, and would specify unmodified proteins of mol. wts. 39,000 and 54,000, respectively. the derived amino acid sequences indicate that these genes are equivalent to the human mitochondrial urfs 1 and 4, with 39% amino acid homology for urf1 and 26% for urf4. both urfs were shown by secondary ...198311894959
activation of the aspergillus pacc zinc finger transcription factor requires two proteolytic steps.the aspergillus pacc transcription factor undergoes proteolytic activation in response to alkaline ambient ph. in acidic environments, the 674 residue translation product adopts a 'closed' conformation, protected from activation through intramolecular interactions involving the < or = 150 residue c-terminal domain. ph signalling converts pacc to an accessible conformation enabling processing cleavage within residues 252--254. we demonstrate that activation of pacc requires two sequential proteol ...200211889040
oxidative stress-induced calcium signalling in aspergillus nidulans.the effects of oxidative stress on levels of calcium ion (ca(2+)) in aspergillus nidulans were measured using strains expressing aequorin in the cytoplasm (aeq(cyt)) and mitochondria (aeq(mt)). when oxidative stress was induced by exposure to 10-mm h(2)o(2), the mitochondrial calcium response (ca(mt)(2+)) was greater than the change in cytoplasmic calcium (ca(c)(2+)). the ca(mt)(2+) response to h(2)o(2) was dose dependent, while the increase in [ca(c)(2+)] did not change with increasing h(2)o(2) ...200211882388
quantitative analysis of the relative transcript levels of abc transporter atr genes in aspergillus nidulans by real-time reverse transcription-pcr assay.the development of assays for quantitative analysis of the relative transcript levels of abc transporter genes by real-time reverse transcription-pcr (rt-pcr) might provide important information about multidrug resistance in filamentous fungi. here, we evaluate the potential of real-time rt-pcr to quantify the relative transcript levels of abc transporter atr genes from aspergillus nidulans. the atra to atrd genes showed different and higher levels in the presence of structurally unrelated drugs ...200211872487
novel alpha-glucosidase from aspergillus nidulans with strong transglycosylation activity.aspergillus nidulans possessed an alpha-glucosidase with strong transglycosylation activity. the enzyme, designated alpha-glucosidase b (agdb), was purified and characterized. agdb was a heterodimeric protein comprising 74- and 55-kda subunits and catalyzed hydrolysis of maltose along with formation of isomaltose and panose. approximately 50% of maltose was converted to isomaltose, panose, and other minor transglycosylation products by agdb, even at low maltose concentrations. the agdb gene was ...200211872475
pcp1p, an spc110p-related calmodulin target at the centrosome of the fission yeast schizosaccharomyces pombe.in the budding yeast saccharomyces cerevisiae, the calmodulin-binding protein spc110p/nuf1p facilitates mitotic spindle formation from the fungal centrosome or spindle pole body (spb). the human spc110p orthologue kendrin is a centrosomal, calmodulin-binding pericentrin isoform that is specifically overexpressed in carcinoma cells. here we establish an evolutionary and functional link between spc110p and kendrin through identification and analysis of similar calmodulin-binding proteins in the fi ...200211864908
genetic control of extracellular protease synthesis in the yeast yarrowia lipolytica.depending on the ph of the growth medium, the yeast yarrowia lipolytica secretes an acidic protease or an alkaline protease, the synthesis of which is also controlled by carbon, nitrogen, and sulfur availability, as well as by the presence of extracellular proteins. previous results have indicated that the alkaline protease response to ph was dependent on ylrim101p, ylrim8p/ylpalf, and ylrim21p/ylpalh, three components of a conserved ph signaling pathway initially described in aspergillus nidula ...200211861549
differential esterase expression in developmental mutants of aspergillus nidulans.esterase isozymes were used to detect substrate-preference polymorphism in five strains of aspergillus nidulans, and to show differential gene expression in developmental mutants in response to 5-azacytidine treatment. the medusa mutants b116, sm23, and m25 were selected in the presence of 5-azacytidine (5ac); also the g839 bristle mutant obtained in the absence of 5ac as well as the ut196 master strain and the normal segregant sm24 were used for the esterase studies. the esterase isozyme patter ...200111860199
evidence that gamma-aminobutyric acid is a major nitrogen source during cladosporium fulvum infection of tomato.the growth of the biotrophic pathogen cladosporium fulvum within the tomato (lycopersicon esculentum mill.) leaf is restricted to the intercellular space. previous studies from this laboratory have demonstrated that gamma-aminobutyric acid (gaba) accumulates to millimolar concentrations in the apoplast during a compatible interaction. we decided to further investigate the role of gaba during infection. a gene encoding a required enzyme for gaba metabolism, gaba transaminase (gat1), was cloned an ...200211855646
functional characterization and localization of the aspergillus nidulans formin sepa.formins are a family of multidomain scaffold proteins involved in actin-dependent morphogenetic events. in aspergillus nidulans, the formin sepa participates in two actin-mediated processes, septum formation and polarized growth. in this study, we use a new null mutant to demonstrate that sepa is required for the formation of actin rings at septation sites. in addition, we find that a functional sepa::gfp fusion protein localizes simultaneously to septation sites and hyphal tips, and that sepa c ...200211854405
a quantity control mechanism regulating levels of the hape subunit of the hap complex in aspergillus nidulans: no accumulation of hape in hapc deletion mutants.the aspergillus nidulans ccaat-binding complex (hap complex) consists of at least three subunits, hapb, hapc and hape. to investigate the quantity control mechanisms of the subunits during assembly of the hap complex, reconstitution studies with the recombinant subunits and extracts prepared from the respective hap subunit deletion mutants were carried out. furthermore, western blot analysis of the hap subunits and northern blot analysis of the hap genes with the respective deletion mutants were ...200211852085
molecular evaluation of the plasma membrane proton pump from aspergillus fumigatus.the gene encoding the plasma membrane proton pump (h+ -atpase) of aspergillus fumigatus, pma1, was characterized from a. fumigatus strain nih 5233 and clinical isolate h11-20. an open reading frame of 3,109 nucleotides with two introns near the n terminus predicts a protein consisting of 989 amino acids with a molecular mass of approximately 108 kda. the predicted a. fumigatus enzyme is 89 and 51% identical to h+ - atpases of aspergillus nidulans and saccharomyces cerevisiae, respectively. the a ...200211850239
the genes gmda, encoding an amidase, and bzua, encoding a cytochrome p450, are required for benzamide utilization in aspergillus nidulans.two unlinked loci, gmda and bzua, have previously been identified as being required for the utilization of benzamide as the sole nitrogen source by aspergillus nidulans. we have cloned each of these genes via direct complementation. the gmda gene encodes a predicted product belonging to the amidase signature sequence family that displays similarity to amds from a. nidulans. however, identity is significantly higher to the amds gene from aspergillus niger. the bzua gene encodes a protein belongin ...200211848676
expression of drosophila melanogaster xanthine dehydrogenase in aspergillus nidulans and some properties of the recombinant enzyme.recent crystal structures of xanthine dehydrogenase, xanthine oxidase and related enzymes have paved the way for a detailed structural and functional analysis of these enzymes. one problem encountered when working with these proteins, especially with recombinant protein, is that the preparations tend to be heterogeneous, with only a fraction of the enzyme molecules being active. this is due to the incompleteness of post-translational modification, which for this protein is a complex, and incompl ...200211829759
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