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in vitro activity of 1,3-beta-d-glucan synthase requires the gtp-binding protein rho1.in the yeast saccharomyces cerevisiae, the family of rho genes are implicated in the control of morphogenetic events although the molecular targets of these gtp-binding proteins remain largely unknown. the activity of 1,3-beta-d-glucan synthase, the product of which is essential for cell wall integrity, is regulated by a gtp-binding protein, which we here present evidence to be rho1p. rho1p was found to copurify with fks1p, a glucan synthase subunit, in preparations of the enzyme purified by pro ...19968662910
the glucose repressor gene cre1 of trichoderma: isolation and expression of a full-length and a truncated mutant form.the cre1 genes of the filamentous fungi trichoderma reesei and t. harzianum were isolated and characterized. the deduced crei proteins are 46% identical to the product of the glucose repressor gene crea of aspergillus nidulans, encoding a dna-binding protein with zinc fingers of the c2h2 type. the cre1 promoters contain several sequence elements that are identical to the previously identified binding sites for a. nidulans crea. steady-state mrna levels for cre1 of the t. reesei strain qm9414 var ...19968709949
control of metabolic flux through the quinate pathway in aspergillus nidulans.the quinic acid ulitization (qut) pathway in aspergillus nidulans is a dispensable carbon utilization pathway that catabolizes quinate to protocatechuate via dehydroquinate and dehydroshikimate(dhs). at the usual in vitro growth ph of 6.5, quinate enters the mycelium by means of a specific permease and is converted into pca by the sequential action of the enzymes quinate dehydrogenase, 3-dehydroquinase and dhs dehydratase. the extent of control on metabolic flux exerted by the permease and the t ...19968670107
regulation of acid phosphatases in an aspergillus niger pacc disruption strain.an aspergillus niger strain has been constructed in which the ph-dependent regulatory gene, pacc, was disrupted. the pacc gene of a. niger, like that of a. nidulans, is involved in the regulation of acid phosphatase expression. disruptants were identified by a reduction in acid phosphatase staining of colonies. southern analysis demonstrated integration of the disruption plasmid at the pacc locus and northern analysis showed that the disruption strain produced a truncated pacc mrna of 2.2 kb (as ...19968709960
two s-phase checkpoint systems, one involving the function of both bime and tyr15 phosphorylation of p34cdc2, inhibit nima and prevent premature mitosis.we demonstrate that there are at least two s-phase checkpoint mechanisms controlling mitosis in aspergillus. the first responds to the rate of dna replication and inhibits mitosis via tyrosine phosphorylation of p34cdc2. cells unable to tyrosine phosphorylate p34cdc2 are therefore viable but are unable to tolerate low levels of hydroxyurea and prematurely enter lethal mitosis when s-phase is slowed. however, if the nima mitosis-promoting kinase is inactivated then non-tyrosine-phosphorylated p34 ...19968670863
quantitative analysis of gene expression in sexual structures of aspergillus nidulans by sequencing of 3'-directed cdna clones.we constructed a 3'-directed cdna library of cleistothecia and hülle cells of aspergillus nidulans to examine gene expression patterns of the sexual structures and to have probes necessary to isolate sexual structure-specific genes. sequencing of 360 randomly selected cdna clones yielded 272 expressed sequence tags (ests), most of which probably represent frequently or less expressed genes in sexual structures of a. nidulans. among the 272 ests, 33 ests (87 cdna clones) appeared more than once a ...19968674973
characterisation of the aspergillus nidulans fra1 mutant: hexose phosphorylation and apparent lack of involvement of hexokinase in glucose repression.hexose phosphorylation was studied in aspergillus nidulans wild-type and in a fructose non-utilising mutant (fra). the data indicate the presence of at least one hexokinase and one glucokinase in wild-type a. nidulans, while the fra1 mutant lacks hexokinase activity. the a. nidulans gene encoding hexokinase was isolated by complementation of the fra1 mutation. the absence of hexokinase activity in the fra1 mutant did not interfere with glucose repression of the enzymes involved in alcohol and l- ...19968674991
identification of a major cis-acting dna element controlling the bidirectionally transcribed penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) of aspergillus nidulans.the beta-lactam antibiotic penicillin is produced as a secondary metabolite by some filamentous fungi. in this study, the molecular regulation of the aspergillus (emericella) nidulans penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) was analyzed. acva and ipna are divergently oriented and separated by an intergenic region of 872 bp. translational fusions of acva and ipna with the two escherichia coli reporter genes lacz and uida enabled us to measure the regulation of both genes simult ...19968682797
nucleotide sequence and expression of the gene encoding nadp+- dependent glutamate dehydrogenase (gdha) from agaricus bisporus.the gene encoding nadp+-dependent glutamate dehydrogenase (gdha) was isolated from an agaricus bisporus recombinant phage lambda library. the deduced amino acid sequence would specify a 457-amino acid protein that is highly homologous in sequence to those derived from previously isolated and characterized genes coding for microbial nadp+-gdh. the open reading frame is interrupted by six introns. none of the introns is located at either one of the positions of the two introns conserved in the cor ...19968602149
purification and properties of beta-galactosidase from aspergillus nidulans.beta-galactosidase from mycelial extract of aspergillus nidulans has been purified by substrate affinity chromatography and used to obtain anti-beta-galactosidase polyclonal antibodies. a. nidulans growing in lactose as carbon source synthesizes one active form of beta-galactosidase which seems to be a multimeric enzyme of 450 kda composed of monomers with 120 and 97 kda. although the enzyme was not released to the culture medium, some enzymatic activity was detected in a cell-wall extract, thus ...19969018692
influence of zinc oxide on aspergillus species: a possible cause of local, non-invasive aspergillosis of the maxillary sinus.recently the appearance of radiopaque 'concrements' in the maxillary sinus was reported. these radiodense objects could be identified as root-filling material for teeth of the upper jaw containing zinc oxide. this suggested that excess root-filling material containing zinc oxide in the maxillary sinus could favour the formation of a local, non-invasive aspergillosis. to verify this hypothesis in vitro, we tested the influence of zinc oxide on aspergillus fumigatus, a. flavus, a. terreus, a. nidu ...19969009659
separation and partial purification of beta-glucosidase and two endoglucanases in aspergillus niveus.the thermotolerant aspergillus niveus strain rmf 7883 was grown in czapek medium, with filter paper cellulose. the proportion of mycelial-bound to extracellular enzymes was studied. most of the beta-glucosidase (80.9%) and endoglucanases (78.3%) activities were extracellular. the extracellular endoglucanases and beta-glucosidase were separated and partially purified by sephadex g-100 gel filtration, followed by ion exchange chromatography on cm-trisacryl m. two extracellular endoglucanases, eg i ...19969019140
isolation of laccase gene-specific sequences from white rot and brown rot fungi by pcr.degenerate primers corresponding to the consensus sequences of the copper-binding regions in the n-terminal domains of known basidiomycete laccases were used to isolate laccase gene-specific sequences from strains representing nine genera of wood rot fungi. all except three gave the expected pcr product of about 200 bp. computer searches of the databases identified the sequence of each of the pcr products analyzed as a laccase gene sequence, suggesting the specificity of the primers. pcr product ...19968837429
cloning, molecular analysis and insertional mutagenesis of the bidirectional hydrogenase genes from the cyanobacterium anacystis nidulans.among cyanobacteria, the heterocystous, n2-fixing anabaena variabilis and the unicellular anacystis nidulans have recently been shown to possess an nad+-dependent, bidirectional hydrogenase. a 5.0 kb dna segment of the a. nidulans genome is now identified to harbor the structural genes hoxuyh coding for three subunits of the bidirectional hydrogenase. the gene arrangement in a. nidulans and in a. variabilis is remarkably dissimilar. in a. nidulans, but not in a. variabilis, the four accessory ge ...19968843154
conformational changes and the role of metals in the mechanism of type ii dehydroquinase from aspergillus nidulans.we have investigated the involvement of metal ions and conformational changes in the elimination reaction catalysed by type ii dehydroquinase from aspergillus nidulans. mechanistic comparisons between dehydroquinases and aldolases raised the possibility that, by analogy with type ii aldolases, type ii dehydroquinases may require bivalent metal ions for activity. this hypothesis was tested by a combination of metal analysis, effects of metal chelators and denaturation/renaturation experiments, al ...19968870678
isolation of two apsa suppressor strains in aspergillus nidulans.aspergillus nidulans reproduces asexually with single nucleated conidia. in apsa (anucleate primary sterigmata) strains, nuclear positioning is affected and conidiation is greatly reduced. to get further insights into the cellular functions of apsa, aconidial apsa strains were mutagenized and conidiating suppressor strains were isolated. the suppressors fell into two complementation groups, sama and samb (suppressor of anucleate metulae), sama mapped on linkage group 1 close to pyrg. the mutant ...19968889518
rna-mediated transformation in aspergillus nidulans recovers gene functions lost by deletion or by point mutations.this work presents the results on two different approaches of rna-mediated transformation in a. nidulans: a) the receptor strain was an argb2 (iii) mutant deficient in arginine (otcase deficient), and b) the receptor was an a. nidulans mutant defective in nitrate reductase synthesis due to a deletion in the niad gene (viii). the analyses of the arg+ and the nia+ retrotransformants allowed an insight on the fate and inheritance of the newly acquired characteristics. the occurrence and the study o ...19968891357
an extragenic suppressor of the mitosis-defective bimd6 mutation of aspergillus nidulans codes for a chromosome scaffold protein.we previously identified a gene, bimd, that functions in chromosome segregation and contains sequences suggesting that it may be a dna-binding protein. two conditionally lethal mutations in bimd arrest with aberrant mitotic spindles at restrictive temperature. these spindles have one-third the normal number of microtubules, and the chromosomes never attach to the remaining microtubules. for this reason, we hypothesized that bimd functioned in chromosome segregation, possibly as a component of th ...19968849887
ca(2+)/calmodulin-dependent kinase is essential for both growth and nuclear division in aspergillus nidulans.the calmodulin gene has been shown to be essential for cell cycle progression in a number of eukaryotic organisms. in vertebrates and aspergillus nidulans the calmodulin dependence also requires calcium. we demonstrate that the unique gene encoding a multifunctional calcium/calmodulin-dependent protein kinase (camk) is also essential in a. nidulans. this enzyme is required both for the nuclear division cycle and for hyphal growth, because spores containing the disrupted gene arrest with a single ...19968898358
cytokinesis in aspergillus nidulans is controlled by cell size, nuclear positioning and mitosis.the mycelium of aspergillus nidulans is composed of multinucleate cellular compartments delimited by crosswalls called septa. septum formation is dependent on mitosis and requires the recruitment of actin to the site of septum formation. employing a collection of temperature sensitive nuclear distribution (nuda2, nudc3 and nudf7), nuclear division (nima5, hfab3), and septation (sepd5, sepg1) mutants, we have investigated the interdependency among nuclear positioning, mitosis, and cell growth in ...19968856514
aspergillus nidulans stcp encodes an o-methyltransferase that is required for sterigmatocystin biosynthesis.the aspergillus nidulans stcp gene was previously identified as a transcribed region associated with a cluster of genes proposed to be involved in sterigmatocystin biosynthesis (d. w. brown, j.-h. yu, h. s. kelkar, m. fernandes, t. c. nesbitt, n. p. keller, t. h. adams, and t. j. leonard, proc. natl. acad. sci. usa 93:1418-1422, 1996). stcp was predicted to encode a methyltransferase responsible for conversion of demethylsterig-matocystin to sterigmatocystin. here we demonstrate that disruption ...19968900026
three binding sites for the aspergillus nidulans pacc zinc-finger transcription factor are necessary and sufficient for regulation by ambient ph of the isopenicillin n synthase gene promoter.the isopenicillin n synthase (ipna) gene, encoding a key penicillin biosynthetic enzyme in aspergillus nidulans, represents a prototype of an alkaline-expressed gene. ipna is under ambient ph regulation, and its promoter (ipnap) contains binding sites for the zinc-finger transcription factor pacc. we show here that three of these sites, denoted ipna2, ipna3, and ipna4ab, are efficiently recognized by the protein in an isolated sequence context. single, double, and triple inactivation of these si ...19968910527
identification, isolation and sequence of the aspergillus nidulans xlnc gene encoding the 34-kda xylanase.the xlnc gene encoding the 34-kda xylanase (x34) of aspergillus nidulans (an) has been cloned and sequenced, as has its corresponding cdna. xlnc contains nine introns and shows considerable similarity to the xyna and xylp xylanase-encoding genes of a. kawachii (ak) and penicillium chrysogenum (pc), respectively. analysis of xylanase production in an multicopy transformants showed elevated levels of x34 and increased total xylanase activity, but no elevated production of other xylanases. northern ...19968917072
molecular cloning of higher plant homologues of the high-affinity nitrate transporters of chlamydomonas reinhardtii and aspergillus nidulans.the crna nitrate transporter from aspergillus nidulans was identified as belonging to the major facilitator superfamily (mfs) of membrane transporters. degenerate oligonucleotides corresponding to the crna sequences at the locations of two conserved sequence motifs were designed and used in the polymerase chain reaction (pcr) to amplify related sequences from barley root poly(a)+ rna. a 130 bp cdna fragment with sequence similarities to crna was amplified and used as a probe to screen a barley r ...19968917103
a temperature-sensitive splicing mutation in the bimg gene of aspergillus produces an n-terminal fragment which interferes with type 1 protein phosphatase function.progression through anaphase requires high levels of type 1 protein phosphatase (pp1) activity in a variety of eukaryotes, including aspergillus nidulans. a conditional lethal, temperature-sensitive mutant in one of the aspergillus pp1 genes, bimg, prevents the normal completion of anaphase when cells are grown at restrictive temperature and this has been shown to be due to a reduction in type 1 phosphatase activity. we show that the bimg11 allele is recessive to the wild-type allele in heterozy ...19968887549
identification of bime as a subunit of the anaphase-promoting complex.the initiation of anaphase and exit from mitosis require the activation of a proteolytic system that ubiquitinates and degrades cyclin b. the regulated component of this system is a large ubiquitin ligase complex, termed the anaphase-promoting complex (apc) or cyclosome. purified xenopus laevis apc was found to be composed of eight major subunits, at least four of which became phosphorylated in mitosis. in addition to cdc27, cdc16, and cdc23, apc contained a homolog of aspergillus nidulans bime, ...19968895470
identification of subunits of the anaphase-promoting complex of saccharomyces cerevisiae.entry into anaphase and proteolysis of b-type cyclins depend on a complex containing the tetratricopeptide repeat proteins cdc16p, cdc23p, and cdc27p. this particle, called the anaphase-promoting complex (apc) or cyclosome, functions as a cell cycle-regulated ubiquitin-protein ligase. two additional subunits of the budding yeast apc were identified: the largest subunit, encoded by the apc1 gene, is conserved between fungi and vertebrates and shows similarity to bimep from aspergillus nidulans. a ...19968895471
the aspergillus flba rgs domain protein antagonizes g protein signaling to block proliferation and allow development.flba encodes an aspergillus nidulans rgs (regulator of g protein signaling) domain protein that is required for control of mycelial proliferation and activation of asexual sporulation. we identified a dominant mutation in a second gene, fada, that resulted in a very similar phenotype to flba loss-of-function mutants. analysis of fada showed that it encodes the alpha-subunit of a heterotrimeric g protein, and the dominant phenotype resulted from conversion of glycine 42 to arginine (fada(g42r)). ...19968895563
parods--a study of parallel algorithms for ordering dna sequences.a suite of parallel algorithms for ordering dna sequences (termed parods) is presented. the algorithms in parods are based on an earlier serial algorithm, ods, which is a physical mapping algorithm based on simulated annealing. parallel algorithms for simulated annealing based on markov chain decomposition are proposed and applied to the problem of physical mapping. perturbation methods and problem-specific annealing heuristics are proposed and described. implementations of parallel single instr ...19968902353
delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase is a rate limiting enzyme for penicillin production in aspergillus nidulans.the acva gene from aspergillus nidulans encoding delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) synthetase was overexpressed by replacing the wild-type acva promoter with the ethanol dehydrogenase promoter, alcap, from a. nidulans. the expression level of alcap was determined using a strain in which the reporter gene, lacz, is under the control of alcap, and was found to be up to 100 times greater than that from the acva promoter when induced in fermentation conditions. penicillin yields ...19969003303
20s cyclosome complex formation and proteolytic activity inhibited by the camp/pka pathway.the 20s cyclosome complex (also known as the anaphase-promoting complex) has ubiquitin ligase activity and is required for mitotic cyclin destruction and sister chromatid separation. the formation and activation of the 20s cyclosome complex is regulated by an unknown mechanism. here we show that cut4 (ref. 6) is an essential component of the cyclosome in fission yeast. cut4 shares sequence similarity with bime, a protein that regulates mitosis in aspergillus nidulans. mutations in cut4 result in ...19968918880
induction of beta-oxidation enzymes and microbody proliferation in aspergillus nidulans.aspergillus nidulans is able to grow on oleic acid as sole carbon source. characterization of the oleate-induced beta-oxidation pathway showed the presence of the two enzyme activities involved in the first step of this catabolic system: acyl-coa oxidase and acyl-coa dehydrogenase. after isopicnic centrifugation in a linear sucrose gradient, microbodies (peroxisomes) housing the beta-oxidation enzymes, isocitrate lyase and catalase were clearly resolved from the mitochondrial fraction, which con ...19968929280
asm-1+, a neurospora crassa gene related to transcriptional regulators of fungal development.this report describes the identification, cloning, and molecular analysis of asm-1+ (ascospore maturation 1), the neurospora crassa homologue of the aspergillus nidulans stua (stunted a) gene. the asm-1+ gene is constitutively transcribed and encodes an abundant, nucleus-localized 68.5-kd protein. the protein product of asm-1+ (asm-1), contains a potential dna-binding motif present in related proteins from a. nidulans (stua), candida albicans (efgtf-1), and saccharomyces cerevisiae (phd1 and sok ...19968913744
sequence analysis and expression of the penicillium chrysogenum nitrate reductase encoding gene (niad).the nitrate reductase gene (niad) of the filamentous fungus penicillium chrysogenum encodes a protein of 864 amino acids. the derived protein sequence shows 78% and 72% sequence identity to the corresponding aspergillus niger and a. nidulans proteins, respectively. the coding region of the penicillium gene is interrupted by six small introns, as deduced by comparison with the niad sequences of a. niger and a. nidulans, whereby the positions of the introns are perfectly conserved between these th ...19968950182
the chsb gene of aspergillus nidulans is necessary for normal hyphal growth and development.the chsb gene from aspergillus nidulans encodes a class iii chitin synthase, an enzyme class found in filamentous fungi but not in yeast-like organisms. using a novel method, we isolated haploid segregants carrying a disrupted chsb allele from heterozygous diploid disruptants. the haploid disruptants grow as minute colonies that do not conidiate. hyphae from the disruptants have enlarged tips, a high degree of branching, and disorganized lateral walls. the mycelium is not deficient in chitin con ...19968953267
gene expression from replicating plasmids in aspergillus nidulans.plasmids bearing the ama1 replicator from aspergillus nidulans are capable of extrachromosomal replication in this fungus as well as in other species. synthetic plasmids bearing the moderately expressed argb gene and the highly expressed, inducible beta-galactosidase gene (bgas) were introduced into fungal cells. expression of both genes was monitored by northern hybridization. it was demonstrated that transcription of bgas is induced and repressed normally, irrespective of whether the gene is i ...19969003309
expression of human recombinant beta 2-microglobulin by aspergillus nidulans and its activity.the light chain of hla class i protein (beta 2m) has been expressed in aspergillus nidulans. the cdna of beta 2m was modified using the polymerase chain reaction to include overlapping extensions for its subsequent fusion into an aspergillus vector. this fusion resulted in beta 2m cdna being flanked by the aspergillus awamori glucoamylase promoter and the aspergillus niger glucoamylase terminator. expression of beta 2m was induced by the addition of starch to the culture medium. in preliminary m ...19968960907
aspergillus has distinct fatty acid synthases for primary and secondary metabolism.aspergillus nidulans contains two functionally distinct fatty acid synthases (fass): one required for primary fatty acid metabolism (fas) and the other required for secondary metabolism (sfas). fas mutants require long-chain fatty acids for growth, whereas sfas mutants grow normally but cannot synthesize sterigmatocystin (st), a carcinogenic secondary metabolite structurally and biosynthetically related to aflatoxin. sfas mutants regain the ability to synthesize st when provided with hexanoic ac ...19968962148
allotopic expression of mitochondrial atp synthase genes in nucleus of saccharomyces cerevisiae. 19968965711
hyma (hypha-like metulae), a new developmental mutant of aspergillus nidulans.asexual fruiting body development in aspergillus nidulans requires a precise spatial and temporal coordinated expression of many genes. insertional mutagenesis was used to isolate and characterize a new mutant of a. nidulans in which hyphal growth was slightly reduced and conidiophore development was specifically blocked at the metula stage. in contrast to the uninucleate metulae of the wild-type, in the mutant these structures were elongated, multinucleate and septate. further differentiation a ...19968969518
aspergillus fabm encodes an essential product that is related to poly(a)-binding proteins and activates development when overexpressed.overexpression of several different aspergillus nidulans developmental regulatory genes has been shown to cause inappropriate developmental activation and growth inhibition. we previously exploited this observation that induced development caused growth inhibition in designing a screen to identify other genes that could activate development when overexpressed. we identified 16 mutants in which induced expression of different random genomic dna sequences caused growth inhibition, accumulation of ...19968978035
analysis of cre1 binding sites in the trichoderma reesei cbh1 upstream region.a 1.5-kb xbai-sacii fragment containing the upstream region of the trichoderma reesei cellobiohydrolase i gene (cbh1) has been sequenced. the 1.5-kb fragment contains eight 6-bp sites having an identical or similar sequence to the consensus sequence for binding a catabolite repressor, aspergillus nidulans crea. results of binding assays with the maltose-binding protein::cre1(10-131) fusion protein (cre1 is a catabolite repressor of t. reesei) and the cbh1 upstream region revealed that a 504-bp x ...19968978090
characterization of a protease deficient strain of penicillium roqueforti generated by heterologous plasmid integration: potential use for protein production.a strain of penicillium roqueforti was transformed with a plasmid which confers resistance to phleomycin. stable transformants were selected. they all present a high resistance to the antibiotic. their proteolytic activity was tested. one transformant is a proteolytic deficient strain unable to degrade casein. it is characterized by a tandem integration of the transformant vector in one site of the genome. the extracellular proteins profile of the strain reveals the absence of a 43 kda polypepti ...19968987631
sequence-specific binding sites in the taka-amylase a g2 promoter for the crea repressor mediating carbon catabolite repression.the n-terminal part of the crea protein encompassing two zinc fingers was expressed in escherichia coli as a fusion protein with the maltose binding protein (male) of e. coli. our results show that crea binds to the promoter of the taa-g2 gene encoding taka-amylase a of aspergillus oryzae. dnase i footprinting experiments showed that crea bound to three sites with high affinity and to one site with low affinity within the first 401-bp region upstream of the transcription initiation site. all of ...19968987852
molecular characterisation of meab, a novel gene affecting nitrogen metabolite repression in aspergillus nidulans.mutations within the meab gene elicit the inappropriate expression of several activities subject to nitrogen metabolite repression in aspergillus nidulans and also have some unrelated phenotypic effects. we have cloned meab and isolated a full length cdna clone. northern analysis has shown that meab expression is not subject to nitrogen metabolite repression. meab encodes a novel protein of 418 amino acids and contains a significantly high number of s/tpxx motifs, a motif common in transcription ...19968690087
the detection and evaluation of aneugenic chemicals.although aneuploidy makes a significant contribution to both somatic and inherited disease the mechanisms by which environmental chemicals may induce numerical chromosome aberrations are only poorly defined. the european union project was aimed to further our understanding of those chemical interactions with the components of the mitotic and meiotic cell division cycle which may lead to aneuploidy and to characterise the parameters such as cellular metabolism which may influence the activity of ...19968692188
the genes yni1 and ynr1, encoding nitrite reductase and nitrate reductase respectively in the yeast hansenula polymorpha, are clustered and co-ordinately regulated.the nitrite reductase-encoding gene (yni1) from the yeast hansenula polymorpha was isolated from a lambda embl3 h. polymorpha genomic dna library, using as a probe a 481 bp dna fragment from the gene of aspergillus nidulans encoding nitrite reductase (niia). an open reading frame of 3132 bp, encoding a putative protein of 1044 amino acids with high similarity with nitrite reductases from fungi, was located by dna sequencing in the phages lambdanb5 and lambdaja13. genes yni1 and ynr1 (encoding ni ...19968694791
transformation of aspergillus nidulans by rna from rat macrophages stimulated with lipopolysaccharide.exogenous rna molecules can be incorporated into eukaryotic cells and can exert a variety of biological effects. we have previously described a model system for correcting genetic alterations of an aspergillus nidulans mutant using homologous rna and this phenomenon was named retrotransformation. in the present study, the retrotransformation of a. nidulans was performed with heterologous rna which was extracted from rat macrophages stimulated with lipopolysaccharide (lps). protoplasts of a. nidu ...19968696260
a novel family of developmentally regulated mammalian transcription factors containing the tea/atts dna binding domain.we describe the molecular cloning of two novel human and murine transcription factors containing the tea/atts dna binding domain and related to transcriptional enhancer factor-1 (tef-1). these factors bind to the consensus tea/atts cognate binding site exemplified by the gt-iic and sph enhansons of the sv40 enhancer but differ in their ability to bind cooperatively to tandemly repeated sites. the human tefs are differentially expressed in cultured cell lines and the mouse (m)tefs are differentia ...19968702974
the quta activator and qutr repressor proteins of aspergillus nidulans interact to regulate transcription of the quinate utilization pathway genese.genetic evidence suggests that the activity of the native quta transcription activator protein is negated by the action of the qutr transcription repressor protein. when aspergillus nidulans was transformed with plasmids containing the wild-type quta gene, transformants that constitutively expressed the quinate pathway enzymes were isolated. the constitutive phenotype of these transformants was associated with an increased copy number of the transforming quta gene and elevated quta mrna levels. ...19968704987
the ribosome-inactivating protein restrictocin deters insect feeding on aspergillus restrictus.the fungus-feeding beetle, carpophilus freemani, consumed equal quantities of young mycelia, fewer phialides bearing mature spores and much fewer phialides bearing developing spores of aspergillus restrictus compared to those of aspergillus nidulans when tested in diet choice assays. the degree to which specific fungal structures were consumed was inversely related to the localization of high levels of restrictocin, a ribosome-inactivating protein, to those structures. pure restrictocin added to ...19968704996
the aspergillus nidulans penicillin-biosynthesis gene aat (pende) is controlled by a ccaat-containing dna element.analysis of the promoter of the penicillin biosynthesis aat (pende) gene of aspergillus nidulans using band-shift assays led to the identification of a ccaat-containing dna element which was specifically bound by a protein (complex). the identified dna element was localised about 250 bp upstream of the transcriptional-start sites of aat. substitution of the ccaat core sequence by gatcc led to a fourfold reduction of expression of an aat-lacz gene fusion. the identified binding site thus was func ...19968706667
the hapc gene of aspergillus nidulans is involved in the expression of ccaat-containing promoters.the 5' regulatory region of the amds gene of aspergillus nidulans, which encodes an acetamidase required for growth on acetamide as a carbon and nitrogen source, contains a ccaat sequence which is required for setting the basal level of amds expression. mobility shift studies have identified a factor in a. nidulans nuclear extracts which binds to this ccaat sequence. in saccharomyces cerevisiae the hap3 gene encodes one component of a multisubunit complex that binds ccaat sequences. a search of ...19968709944
the aspergillus nidulans genes chsa and chsd encode chitin synthases which have redundant functions in conidia formation.we previously isolated three chitin synthase genes (chsa, chsb, and chsc) from aspergillus nidulans. in the present work, we describe the isolation and characterization of another chitin synthase gene, named chsd, from a. nidulans. its deduced amino acid sequence shows 56.7% and 55.9% amino acid identity, respectively, with cal1 of saccharomyces cerevisiae and chs3 of candida albicans. disruption of chsd caused no defect in cell growth or morphology during the asexual cycle and caused no decreas ...19968709948
suppression and enhancement of the aspergillus nidulans medusa mutation by altered dosage of the bristle and stunted genes.asexual reproduction in aspergillus nidulans is characterized by the orderly differentiation of multicellular reproductive structures (conidiophores) and chains of uninucleate conidia (spores). mutations in the developmental modifier medusa (meda) result in aberrant conidiophores with branching chains of reiterated reproductive cells (metulae), delayed conidial differentiation and frequent reinitiation of secondary conidiophores. we show that incorrect morphology is in part a consequence of modi ...19968722771
saccharomyces cerevisiae tec1 is required for pseudohyphal growth.diverse eukaryotic organisms share developmental transcription factors with homologous dna-binding domains. we showed that the developmental regulator abaa, a member of the atts/tea (abaa, tef-1, tec1, scalloped/tef-1, tec1, abaa) class of transcription factors of the filamentous fungus aspergillus nidulans, induces pseudohyphal development in the yeast saccharomyces cerevisiae. the s. cerevisiae homologue of abaa, tec1p, is required for this morphological transition. we provide evidence that te ...19968730867
isolation of opportunistic fungi from bronchoalveolar lavage of compromised hosts in isfahan, iran.in this study, bronchoalveolar lavage (bal) specimens from 247 immunocompromised patients were investigated for the incidence of opportunistic fungi. in the direct examination and culture of the specimens, 5 (2.02%) of filamentous fungi and 55 (22.26%) yeasts were isolated and identified as follows: aspergillus fumigatus (2), a. terreus (1), a. nidulans (1), mucor sp. (1), candida albicans (29), c. glabrata (3), c. parapsilosis (1), trichosporon beigelii (1), candida sp. (13) and unknown yeasts ...19968751826
isolation of a gene involved in 1,3-beta-glucan synthesis in aspergillus nidulans and purification of the corresponding protein.saccharomyces cerevisiae has two highly homologous genes, fks1 and fks2, which encode interchangeable putative catalytic subunits of 1,3-beta-glucan synthase (gs), an enzyme that synthesizes an essential polymer of the fungal cell wall. to determine if gs in aspergillus species is similar, an fks homolog, fksa, was cloned from aspergillus nidulans by cross-hybridization, and the corresponding protein was purified. sequence analysis revealed a 5,716-nucleotide coding region interrupted by two 56- ...19968755864
the cyanobacterial thioredoxin gene is required for both photoautotrophic and heterotrophic growth.the gene encoding thioredoxin in the facultative heterotrophic cyanobacterium synechocytis sp. pcc 6803 (trxa) has been cloned by heterologous hybridization using the corresponding gene trxm from the cyanobacterium anacystis nidulans as a probe. the deduced amino acid sequence of trxa predicts a protein of relative molecular weight of 11,750 and has strong identity with its cyanobacterial counterparts and other m-type thioredoxins of photo-synthetic eukaryotes. the trxa gene has been expressed e ...19968756494
nut1, a major nitrogen regulatory gene in magnaporthe grisea, is dispensable for pathogenicity.nut1, a gene homologous to the major nitrogen regulatory genes nit-2 of neurospora crassa and area of aspergillus nidulans, was isolated from the rice blast fungus, magnaporthe grisea. nut1 encodes a protein of 956 amino acid residues and, like nit-2 and area, has a single putative zinc finger dna-binding domain. functional equivalence of nut1 to area was demonstrated by introducing the nut1 gene by dna-mediated transformation into an area loss-of-function mutant of a. nidulans. the introduced n ...19968757395
multiple copies of mate elements support autonomous plasmid replication in aspergillus nidulans.the ama1 sequence is an efficient plasmid replicator and transformation enhancer in aspergillus nidulans. it comprises two long perfect inverted repeats (mate elements) flanking a short, unique, central spacer. subclone analysis indicates that the complete inverted duplication, but not the unique central spacer, is necessary for efficient plasmid replication. the smallest fragments able to affect transformation efficiency lie within the at-rich portions of the inverted repeats. we demonstrate th ...19968733240
the cu,zn superoxide dismutases of aspergillus flavus, aspergillus niger, aspergillus nidulans, and aspergillus terreus: purification and biochemical comparison with the aspergillus fumigatus cu,zn superoxide dismutase.cu,zn superoxide dismutases (sods) have been purified to homogeneity from aspergillus flavus and a. niger, which are significant causative agents of aspergillosis, and from a. nidulans and a. terreus, which are much rarer causative agents of disease, using a combination of isoelectric focusing and gel filtration fast protein liquid chromatography. the purified enzymes have been compared with the previously described sod from the most important pathogen in the genus, a. fumigatus (m. d. holdom, r ...19968757871
a newly identified gene cluster in aspergillus nidulans comprises five novel genes localized in the alc region that are controlled both by the specific transactivator alcr and the general carbon-catabolite repressor crea.ethanol-utilization in aspergillus nidulans is mediated by alcohol dehydrogenase i and aldehyde dehydrogenase encoded by alca and alda, respectively. both genes are under the transcriptional control of the specific activator alcr and the general carbon catabolite repressor crea. the alcr and alca genes are closely linked in chromosome vii; alda is located in chromosome viii. we have identified five other transcripts that are expressed from the same genomic region as alca and alcr. they are induc ...19968736527
cell cycle regulation in aspergillus by two protein kinases.great progress has recently been made in our understanding of the regulation of the eukaryotic cell cycle, and the central role of cyclin-dependent kinases is now clear. in aspergillus nidulans it has been established that a second class of cell-cycle-regulated protein kinases, typified by nima (encoded by the nima gene), is also required for cell cycle progression into mitosis. indeed, both p34cdc2/cyclin b and nima have to be correctly activated before mitosis can be initiated in this species, ...19968760343
the 2.8 a structure of a t = 4 animal virus and its implications for membrane translocation of rna.simple rna animal viruses generally enter cells through receptor-mediated endocytosis followed by acid ph dependent release and translocation of rna across the endosomal membrane. the t = 3 nodaviruses contain prefabricated pentameric helical bundles that are cleaved from the remainder of the subunits by an assembly-dependent auto-proteolysis and they are positioned for release through 5-fold axes of the particle. we previously proposed that these bundles may serve as conduits for rna membrane t ...19968760498
a study of the structural basis of the ability of chlorinated alkanes and alkenes to induce aneuploidy and toxicity in the mold aspergillus nidulans.a knowledge-based system (multicase) was applied to the elucidation of the structural basis of the induction of aneuploidy and growth inhibition by a group of chlorinated alkanes and alkenes in aspergillus nidulans. it was found that while there were commonalities in the structural determinants associated with fungicidal and fungostatic activities, there were none between these and the structures associated with the induction of aneuploidy. moreover, there did not appear to be a commonality betw ...19968764947
[effect of zinc oxide on aspergillus species: a possible cause of local noninvasive aspergillosis of the maxillary sinus].during the last years the appearance of radiopaque concrements in the maxillary sinus was reported. these could be identified as root-filling material for teeth of the upper jaw containing zinc oxide. this suggested that excess root-filling material containing zinc oxide in the maxillary sinus could favour the development of a local, non-invasive aspergillosis. therefore, we tested aspergillus fumigatus, a. flavus, a. terreus, a. nidulans and a. niveus for the influence of zinc oxide. cza-pek-do ...19968767264
mitochondrial inheritance in aspergillus nidulans.mitochondrial chloramphenicol and oligomycin resistance mutations were used to investigate mitochondrial inheritance in a. nidulans. mitochondrial rflps could not be used to distinguish between paternal and maternal mitochondria because none were detected in the 54 isolates investigated. several thousand ascospores from each of 111 hybrid cleistothecia from 21 different crosses between 7 heterokaryon incompatible isolates were tested for biparental inheritance. all mitochondrial inheritance was ...19968801189
characterization of a penicillium chrysogenum gene encoding a pacc transcription factor and its binding sites in the divergent pcbab-pcbc promoter of the penicillin biosynthetic cluster.previous work established that ph regulation of gene expression in aspergillus nidulans, a major determinant of penicillin biosynthesis, is mediated by the zinc-finger transcription factor pacc, an activator of transcription of the isopenicillin n synthase gene. we characterize here the pacc gene from the efficient penicillin producer penicillium chrysogenum, which functionally complements an a. nidulans pacc null mutation. it encodes a 641-residue polypeptide showing 64% identify to a. nidulans ...19968736532
the secondary structure and phylogenetic relationship deduced from complete nucleotide sequence of mitochondrial small subunit rrna in yeast hansenula wingei.we have accomplished the nucleotide sequence of the 1537 bp mitochondrial gene coding for small subunit (ssu) rrna of yeast hansenula wingei, and also determined the 5'- and 3'-termini by s1 nuclease mapping. eight universally conserved (u) elements of the ssu rrna were identified. comparison of u regions among five fungal mitochondrial ssu rrna shows the striking similarity between h. wingei and saccharomyces cerevisiae. the construction of the secondary structure revealed a core structure simi ...19968752867
expression of the sclerotinia sclerotiorum polygalacturonase pg1 gene: possible involvement of crea in glucose catabolite repression.northern-blot analysis of rna isolated from sclerotinia sclerotiorum grown on either glucose or polygalacturonate as the sole carbon source showed that pg1, encoding a neutral polygalacturonase, was not expressed during growth in both media. in contrast, transcripts of this gene were detected during infection of sunflower germlings. analysis of the promoter sequence revealed a number of cis-acting sequences known to regulate the expression of many fungal promoters. protein-dna-binding experiment ...19968753653
on the consistency of a physical mapping method to reconstruct a chromosome in vitro.during recent years considerable effort has been invested in creating physical maps for a variety of organisms as part of the human genome project and in creating various methods for physical mapping. the statistical consistency of a physical mapping method to reconstruct a chromosome, however, has not been investigated. in this paper, we first establish that a model of physical mapping by binary fingerprinting of dna fragments is identifiable using the key assumption-for a large randomly genera ...19968770604
screening of medicinal plants for induction of somatic segregation activity in aspergillus nidulans.knowledge about mutagenic properties of plants commonly used in traditional medicine is limited. a screening for genotoxic activity was carried out in aqueous or alcoholic extracts prepared from 13 medicinal plants widely used as folk medicine in cuba: lepidium virginicum l. (brassicaceae): plantago major l. and plantago lanceolata l. (plantaginaceae); ortosiphon aristatus blume, mentha x piperita l., melissa officinalis l. and plectranthus amboinicus (lour.) spreng. (lamiaceae); cymbopogon citr ...19968771452
isolation and characterization of the nuclease o gene (nuco) from aspergillus oryzae.nuclease o in the mycelia of aspergillus oryzae has been purified 55-fold by successive steps of chromatography from the filtrate of the autolyzate. the molecular mass of nuclease o was 32 kda, as estimated by sds polyacrylamide-gel electrophoresis. the nuclease o gene (nuco) encoding this enzyme was cloned and sequenced. the open reading frame is interrupted by four introns with conserved splice sites and contains 328 amino-acid residues of the mature enzyme. a. nidulans transformants obtained ...19968781174
molecular cloning and expression in saccharomyces cerevisiae of two aspergillus nidulans xylanase genes.two aspergillus nidulans genes, xlna and xlnb, encoding the x22 and x24 xylanases from this fungus, respectively, have been cloned and sequenced. their cdnas have been expressed in a laboratory saccharomyces cerevisiae strain under the control of a constitutive yeast promoter, resulting in the construction of recombinant xylanolytic yeast strains.19968787417
the isolation of a dol-p-man synthase from ustilago maydis that functions in saccharomyces cerevisiae.genomic dnas from several fungi were screened for a homologous sequence to saccharomyces cerevisiae dpm1, an essential gene which encodes dolichyl phosphoryl mannose synthase. the fungi examined included aspergillus nidulans, neurospora crassa, schizophyllum commune and ustilago maydis. only u. maydis gave a significant signal after southern hybridization using dpm1 as a probe. the ustilago homolog was subsequently cloned and sequenced. the predicted protein of 294 amino acids has 60% identity t ...19968813763
isolation and characterization of a calmodulin-encoding cdna from the pathogenic fungus histoplasma capsulatum.we describe in this paper the isolation and complete sequence of a calmodulin (cam) encoding cdna from the dimorphic pathogenic fungus histoplasma capsulatum (genbank accession u12505). the deduced amino acid sequence was identical to the cam of aspergillus nidulans and had only one amino acid difference from the cam of neurospora crassa. saccharomyces cerevisiae cam, however, has only about 60% amino acid identity compared with h. capsulatum. these data further support the close relationship of ...19968803795
purification and partial characterization of the high and low molecular weight form (s- and f-form) of invertase secreted by aspergillus nidulans.two forms of secreted invertase have been purified from aspergillus nidulans by ion-exchange and gel-filtration chromatography. s-invertase gave a single, broad, glycoprotein band on page and sds-page corresponding in size to 185 and 78 kda, respectively, compared with 94 and 110 kda for f-invertase. the carbohydrate of s-invertase contained mainly mannose (14%) and less galactose (5%) whereas the f-form yielded mainly galactose (29%) and less mannose (12%). three sharp bands of enzymically acti ...19968814228
[regulation of folate metabolism in fungi: aspergillus nidulans as an experimental model]. 19968805185
the orla gene from aspergillus nidulans encodes a trehalose-6-phosphate phosphatase necessary for normal growth and chitin synthesis at elevated temperatures.a cosmid carrying the orla gene from aspergillus nidulans was identified by complementation of an orla1 mutant strain with dna from the pkby2 cosmid library. an orla1 complementing fragment from the cosmid was sequenced. orla encodes a predicted polypeptide of 227 amino acids (26360 da) that is homologous to a 211-amino-acid domain from the polypeptide encoded by the saccharomyces cerevisiae tps2 gene and to almost the entire escherichia coli otsb-encoded polypeptide. tps2 and otsb each specify ...19968809779
the chsd and chse genes of aspergillus nidulans and their roles in chitin synthesis.two chitin synthase genes, chsd and chse, were identified from the filamentous ascomycete aspergillus nidulans. in a region that is conserved among chitin synthases, the deduced amino acid sequences of chsd and chse have greater sequence identity to the polypeptides encoded by the saccharomyces cerevisiae chs3 gene (also named csd2, cal1, dit101, and kti1) and the candida albicans chse gene than to other chitin synthases. chse is more closely related to the chs3 genes, and this group constitutes ...19968810520
aspergillus endocarditis in chronic granulomatous disease.we report the first case, to our knowledge, of aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. a diagnosis was made on culture of the organism from the mass despite extensive prior investigation. the presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. we conclude that f ...19968816221
fast dissociation of phe-trna synthetase from aspergillus nidulans immobilized on sepharose-6b column by nacl.phenylalanyl-trna2) synthetase from aspergillus nidulans was efficiently immobilised to sepharose 6b column containing phenylalanine as the ligand. nacl was found to be a potent dissociating agent for the immobilised enzyme. while 0.5 m nacl in discontinuous elution showed a slow impetus on dissociation giving a plateaux profile, a solution of 0.8 m nacl made the elution rapid giving a sharp peak. on the other hand, in a gradient (continuous) elution the rapidity of dissociation was found to be ...19968819846
anaerobic crystallisation of an isopenicillin n synthase.fe(ii).substrate complex demonstrated by x-ray studies.isopenicillin n synthase (ipns) was cocrystallised with ferrous sulphate and its substrate, delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine (aad-cys-val). vital to the successful procedure was the maintenance of a rigorously anaerobic environment. hanging-drop vapour-diffusion crystallisation experiments, using lithium sulphate as the precipitant produced three crystal forms. form i crystals, with a plate habit, diffracted x-rays to at least 0.11-nm resolution at the european synchrotron radia ...19969022704
conservation of structure and function of the aflatoxin regulatory gene aflr from aspergillus nidulans and a. flavus.under limiting growth conditions, aspergillus nidulans produces a carcinogenic secondary metabolite related to aflatoxin and called sterigmatocystin (st). the genes for st biosynthesis are co-ordinately regulated and are all found within an approximately 60-kilobase segment of dna. one of the genes within this region is predicted to encode a cx2cx6cx6cx2cx6cx2 zinc binuclear cluster dna-binding protein that is related to the aspergillus flavus and aspergillus parasiticus aflatoxin regulatory gen ...19968662194
comparative analysis of the qutr transcription repressor protein and the three c-terminal domains of the pentafunctional arom enzyme.the arom protein is a pentadomain protein catalysing steps two to six in the prechorismate section of the shikimate pathway in microbial eukaryotes. on the basis of amino acid sequence alignments and the properties of mutants unable to utilize quinic acid as a carbon source, the arom protein has been proposed to be homologous throughout its length with the proteins regulating transcription of the genes necessary for quinate catabolism. the qutr transcription repressor protein has been proposed t ...19968611179
flug and flba function interdependently to initiate conidiophore development in aspergillus nidulans through brla beta activation.the aspergillus nidulans flug gene is necessary for the synthesis of a small diffusible factor that is required for the endogenously regulated induction of asexual sporulation that takes place during the development of an air-exposed colony. previous work established that flug is present at nearly constant levels throughout the aspergillus life cycle, leading to the hypothesis that flug factor is constitutively produced and development initiates after its concentration surpasses a fixed threshol ...19968617205
identification of a new antifungal target site through a dual biochemical and molecular-genetics approach.the target site of the antifungal compound ly214352 [8-chloro-4-(2-chloro-4-fluorophenoxy) quinoline] has been identified through a dual biochemical and molecular-genetics approach. in the molecular-genetics approach, a cosmid library was prepared from an aspergillus nidulans mutant that was resistant to ly214352 because of a dominant mutation in a single gene. a single cosmid (6a6-6) that could transform an ly214352-sensitive strain of a. nidulans to ly214352-resistance was isolated from the li ...19968660469
identification and cloning of a mobile transposon from aspergillus niger var. awamori.aspergillus niger var. awamori contains multiple copies of a transposable element, vader. this element was detected as a 437-bp insertion in four independently isolated spontaneous mutants of the niad (nitrate reductase) gene. the vader element is present in approximately 15 copies in both a. niger var. awamori and a. niger. a single copy of vader was detected from only one of the two laboratory strains of a. nidulans which were also examined. insertion of the vader element into the niad gene of ...19968625427
phylogenetic analysis of the isopenicillin-n-synthetase horizontal gene transfer.a phylogenetic study of the isopenicillin-n-synthetase (ipns) gene sequence from prokaryotic and lower eukaryotic producers of beta-lactam antibiotics by means of a maximum-likelihood approach has been carried out. after performing an extensive search, rather than invoking a global molecular clock, the results obtained are best explained by a model with three rates of evolution. grouped in decreasing order, these correspond to a. nidulans and then to the rest of the eukaryotes and prokaryotes, r ...19968662005
expression of an erwinia pectate lyase in three species of aspergillus.transgenic filamentous fungi of the species aspergillus niger, a. nidulans and a. awamori expressing and secreting erwinia carotovora subsp. atroseptica pectate lyase 3 (pl3) were generated. correct processing of the pre-enzyme was achieved using the a. niger pectin lyase a (pel a) signal peptide. with the prepro-peptide of a. niger polygalacturonase ii, secreted enzymes still possessed the 6- aa pro-sequence, indicating the importance of the conformation of the precursor protein for correct cle ...19968625428
autonomously replicating plasmids carrying the ama1 region in penicillium chrysogenum.plasmid vectors containing the ama1 sequence transformed with high efficiency and replicated autonomously in penicillium chrysogenum. the efficiency of transformation of p. chrysogenum was related to the length of the ama1 fragment used for constructing the different autonomously replicating plasmids. one of the two palindromic inverted repeats of ama1 (the 2.2-kb sali-hindiii fragment) is sufficient to confer autonomous replication and a high transformation efficiency. deletion of the 0.6-kb ce ...19968625429
endoglucanase ii (egii) of penicillium janthinellum: cdna sequence, heterologous expression and promotor analysis.the cdna coding for the endoglucanase egii of p. janthinellum was cloned and sequenced. the open reading frame comprises 1230 nucleotides and the deduced amino-acid sequence shows an overall homology of 63% with the t. reesei egl2. the cellulose-binding domain of egii represents a typical member of the a family of cellulases. the egl2 gene is only induced by cellulose or cellobiose and not by sophorose. a promotor fragment including 1 kb was cloned and sequenced. three major transcription startp ...19968625430
mutations affecting extracellular protease production in the filamentous fungus aspergillus nidulans.the extracellular proteases of aspergillus nidulans are known to be regulated by carbon, nitrogen and sulphur metabolite repression. in this study, a mutant with reduced levels of extracellular protease was isolated by screening for loss of halo production on milk plates. genetic analysis of the mutant showed that it contains a single, recessive mutation, in a gene which we have designated xpre, located on chromosome vi. the xpre1 mutation affected the production of extracellular proteases in re ...19968628232
purification and characterization of mitochondrial ribonuclease p from aspergillus nidulans.mitochondrial ribonuclease (rnase) p from aspergillus nidulans was purified to near homogeneity using whole-cell extract as the starting material. a 4400-fold purification with a yield of 5.2% was achieved by ammonium sulfate fractionation, heat treatment, and five types of column chromatography, including trna-affinity column chromatography. this enzyme, which has a molecular mass of 232 kda determined by glycerol gradient sedimentation analysis, appears to be composed of seven polypeptides and ...19968631344
the rna component of mitochondrial ribonuclease p from aspergillus nidulans.several rna molecules that copurified with aspergillus nidulans mitochondrial ribonuclease (rnase) p were identified [lee, y c., lee, b. j., hwang, d. s. & kang, h. s. (1996) eur j. biochem. 235, 289-296], and their partial sequences were determined. using an oligonucleotide probe, we cloned and mapped the gene encoding this putative rna component of rnase p (rnase p-rna), situated between urfa3 (unidentified reading frame a3) and coba (apocytochrome b) genes in the mitochondrial genome of a. ni ...19968631345
twenty-five coregulated transcripts define a sterigmatocystin gene cluster in aspergillus nidulans.sterigmatocystin (st) and the aflatoxins (afs), related fungal secondary metabolites, are among the most toxic, mutagenic, and carcinogenic natural products known. the st biosynthetic pathway in aspergillus nidulans is estimated to involve at least 15 enzymatic activities, while certain aspergillus parasiticus, aspergillus flavus, and aspergillus nomius strains contain additional activities that convert st to af. we have characterized a 60-kb region in the a. nidulans genome and find it contains ...19968643646
wild chromosomal variants in aspergillus nidulans.pulsed-field gel electrophoresis and a chromosome-specific cosmid dna library were used to determine the karyotypes of wild-type aspergillus nidulans isolates from around the world. overall, little structural variation was found, with a few major exceptions. one isolate possessed a non-essential b-chromosome of about 1.0 million base pairs (mb). another isolate had undergone a non-reciprocal translocation of about 1.6 mb of chromosome vi onto chromosome viii. other than these chromosomal differe ...19968595677
identification, cloning and analysis of the aspergillus niger gene pacc, a wide domain regulatory gene responsive to ambient ph.a wide domain regulatory gene implicated in modulating gene expression in response to ambient ph has been cloned and sequenced from the industrially useful filamentous fungus aspergillus niger. this gene, pacc, is able to restore a pacc+ phenotype to a. nidulans paccc11 and paccc14 mutants with respect to extent of conidiation, conidial pigment intensity and acid phosphatase regulation. the pacc gene of a. niger comprises three exons, encodes a three-zinc-finger protein of 677 amino acids, and s ...19968602152
gel mobility shift scanning of the acetate-inducible promoters from neurospora crassa reveals a common co-inducible dna-binding protein.the promoter regions of four acetate-inducible genes of neurospora crassa, acu-3, acu-5, acu-8 and acu-9, have been sequenced. using a scanning gel mobility shift assay particular dna regions in each promoter have been shown specifically to bind partially purified protein extracted from acetate-induced mycelia. the protein-binding regions so defined have common sequence motifs, elements of which are similar to those required for acetate induction in aspergillus nidulans.19968602159
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