PMID(sorted ascending)
efficient independent activity of a monomeric, monofunctional dehydroquinate synthase derived from the n-terminus of the pentafunctional arom protein of aspergillus nidulans.the dehydroquinate synthase (dhq synthase) functional domain from the pentafunctional arom protein of aspergillus nidulans has previously been overproduced in escherichia coli [van den hombergh, moore, charles and hawkins (1992) biochem j. 284, 861-867]. we now report the purification of this domain to homogeneity and subsequent characterization. the monofunctional dhq synthase was found to retain efficient catalytic activity when compared with the intact pentafunctional arom protein of neurospo ...19948037684
nitrate reductase of the ascomycetous fungus, leptosphaeria maculans: gene sequence and chromosomal location.the nitrate reductase (niad) gene was isolated from the phytopathogenic loculoascomycete leptosphaeria maculans by screening a genomic dna library with the aspergillus nidulans niad gene. the l. maculans niad gene is the first protein-encoding gene characterised from this fungus. it encodes a predicted protein of 893 amino acids and contains four putative introns at positions in the gene equivalent to those of four of the six introns in the a. nidulans niad gene. mutants defective in niad and mo ...19948041355
synthesis of sterigmatocystin on a chemically defined medium by species of aspergillus and chaetomium.sterigmatocystin (st) is a secondary metabolite and a principal mycotoxin known to be produced by over 30 species of filamentous fungi. it is also one of the late intermediates in aflatoxin biosynthesis. we have tested the ability of 7 species of aspergillus, including 4 strains of a. versicolor, one species of bipolaris, and two species of chaetomium, to produce st on a sucrose-salts-phenylalanine defined medium as well as on three complex substrates. highest st production in our survey was by ...19948047108
enhancers of conidiation mutants in aspergillus nidulans.mutants at a number of loci, designated sthenyo, have been isolated as enhancers of the oligoconidial mutations at the meda locus. two loci have been mapped: stha on linkage group i, and sthb on linkage group v. two probable alleles have been identified at each locus but two further mutants were unlinked to either stha or sthb. neither stha nor sthb mutants have conspicuous effects on morphology on their own, nor could the stha1 sthb2 double mutant be distinguished from wild type. mutants at bot ...19948056325
synechocystis sp. pcc6803 fusb gene, located outside of the str operon, encodes a polypeptide related to protein synthesis factor ef-g.synechocystis sp. pcc6803, a cyanobacterium, possesses an unusual gene (fusb) which encodes a protein with strong homology to protein synthesis elongation factor g (ef-g), although it is not linked to the classical str operon. the fusb gene is redundant, since a synechocystis gene similar to str operon-encoded fusa genes of other bacteria is also present (based on pcr and hybridization results). there is no evidence for the presence of a fusb homologue in other bacteria. the synechocystis fusb g ...19948061323
regulation of the xylanase-encoding xlna gene of aspergillus tubigensis.a gene encoding an endo-1,4-beta-xylanase from aspergillus tubigensis was cloned by oligonucleotide screening using oligonucleotides derived from amino acid sequence data obtained from the purified protein. the isolated gene was functional as it could be expressed in the very closely related fungus aspergillus niger. the xylanase encoded by this gene is synthesized as a protein of 211 amino acids. after cleavage of the presumed prepropeptide this results in a mature protein of 184 amino acids wi ...19948065265
hyphal tip extension in aspergillus nidulans requires the mana gene, which encodes phosphomannose isomerase.a strain of aspergillus nidulans carrying a temperature-sensitive mutation in the mana gene produces cell walls depleted of d-mannose and forms hyphal tip balloons at the restrictive temperature (b.p. valentine and b.w. bainbridge, j. gen. microbiol. 109:155-168, 1978). we have isolated and characterized the mana gene and physically located it between 3.5 and 5.5 kb centromere distal of the ribob locus on chromosome viii. the mana gene contains four introns and encodes a 50.6-kda protein which h ...19948065336
the calmodulin-dependent protein phosphatase catalytic subunit (calcineurin a) is an essential gene in aspergillus nidulans.the gene encoding the homologue of the catalytic subunit of the ca2+/calmodulin-regulated protein phosphatase 2b (calcineurin a) has been isolated from aspergillus nidulans. this gene, cnaa+, is essential in this fungal system. analysis of growth-arrested cells following gene disruption by homologous recombination reveals that they are blocked early in the cell cycle. the cnaa+ gene encodes a 2.5 kb mrna and the deduced protein sequence is highly homologous to the calcineurin a subunit of other ...19948070419
the aspergillus nidulans crea protein mediates glucose repression of the ethanol regulon at various levels through competition with the alcr-specific transactivator.carbon catabolite repression in aspergillus nidulans is mediated by a negative-acting protein coded by the crea gene. we have investigated how crea controls the expression of the ethanol regulon genes. crea is a major component of the control of this regulon. its presence in the cell results in a permanent, albeit partial, repression of the alc genes under all physiological growth conditions, even when the fungus is grown on carbon sources considered to be non-repressing. a crucial step in the c ...19948076597
evolution of transcription-regulating proteins by enzyme recruitment: molecular models for nitrogen metabolite repression and ethanol utilisation in eukaryotes.studies on the quinic acid utilisation gene (qut) cluster in aspergillus nidulans showed that the genes encoding transcriptional activator and repressor proteins evolved by co-opting duplicated copies of genes encoding metabolic enzymes. in order to test the hypothesis that this was a general route for the genesis of regulatory proteins, the origins of the major control protein mediating nitrogen metabolite repression (an example of inter-pathway regulation) and ethanol utilisation (an example o ...19948076813
cloning and characterization of the pda6-1 gene encoding a fungal cytochrome p-450 which detoxifies the phytoalexin pisatin from garden pea.the ability to detoxify pisatin, a phytoalexin produced by garden pea (pisum sativum), is controlled by a family of pda (pisatin demethylating ability) genes in the phytopathogenic fungus nectria haematococa, mp (mating population) vi. six known pda genes each encode characteristic levels of inducible enzyme activity and are associated with different degrees of virulence on pea. to elucidate the phenotypic differences associated with these genes, we have cloned and characterized the pda6-1 gene ...19948076822
the penicillium chrysogenum and aspergillus nidulans weta developmental regulatory genes are functionally equivalent.aspergillus nidulans and penicillium chrysogenum are related fungi that reproduce asexually by forming multicellular conidiophores and uninucleate conidia. in a. nidulans, spore maturation is controlled by the weta (aweta) regulatory gene. we cloned a homologous gene (pweta) from p. chrysogenum to determine if spore maturation is regulated by a similar mechanism in this species. the pweta and aweta genes are similar in structure and functional organization. the inferred polypeptides share 77% ov ...19948078481
a new selection method for isolating mutants defective in acetate utilisation in aspergillus nidulans.propionate medium is normally toxic for the growth of aspergillus nidulans. spontaneous mutations relieving the toxicity to propionate, which arose on propionate medium, have been shown to be mutations in acetate metabolism. one acu- mutant is allelic with acua (the structural gene for acetyl-coa synthetase), another with acub (the regulatory gene involved in the induction of enzymes concerned with acetate metabolism, including acetyl-coa synthetase), and a third mutant, acuo, represents a new a ...19948082165
transformation of trichoderma reesei based on hygromycin b resistance using homologous expression signals.trichoderma reesei was transformed to hygromycin b resistance using a novel vector, which contains the e. coli hygromycin b phosphotransferase gene (hph) fused between promoter and terminator elements of the homologous trichoderma pki1 (coding for pyruvate kinase) and cbh2 (coding for cellobiohydrolase ii) genes, respectively. transformation frequencies of over 1,800--2,500 transformants/micrograms dna were obtained, which is a 15--20-fold increase over that with pan7-1, which contains hph betwe ...19948082210
biolistic transformation of conidia of botryotinia fuckeliana.botryotinia fuckeliana, the causal agent of grey mould, was biolistically transformed to hygromycin b resistance using a plasmid (poht) containing a bacterial hygromycin phosphotransferase gene fused to regulatory sequences from aspergillus nidulans. multiple copies of the plasmid, precipitated onto tungsten particles, were delivered into the conidia by a helium-driven gene gun. southern analysis showed that the plasmid was integrated into the fungal genome at one single locus. after five subseq ...19948087880
toxin-deficient mutants from a toxin-sensitive transformant of cochliobolus heterostrophus.tox1 is the only genetic element identified which controls production of t-toxin, a linear polyketide involved in the virulence of cochliobolus heterostrophus to its host plant, corn. previous attempts to induce toxin-deficient (tox-) mutants, using conventional mutagenesis and screening procedures, have been unsuccessful. as a strategy to enrich for tox- mutants, we constructed a tox1+ strain that carried the corn t-urf13 gene (which confers t-toxin sensitivity) fused to a fungal mitochondrial ...19948088521
characterisation of the gene encoding acetyl-coa synthetase in penicillium chrysogenum: conservation of intron position in plectomycetes.acetyl-coenzyme a synthetase (acs; ec from some plectomycete fungi is possibly involved in an accessory step of penicillin biosynthesis, in addition to its role in primary metabolism. we present the characterisation of the gene encoding this enzyme in penicillium chrysogenum, which we designated acua. sequencing of genomic and cdna clones showed that the coding region was interrupted by five introns, located at the same positions as those present in the aspergillus nidulans homologue. t ...19938103029
two novel deduced serine/threonine protein kinases from saccharomyces cerevisiae.we have cloned genes for two closely related protein kinase (pk) homologues from saccharomyces cerevisiae. sequence alignment of the kinase domain with previously characterized pk reveals the highest degree of similarity with second messenger-regulated kinases. rck1 encodes a 58-kda protein, and is weakly expressed. rck2 encodes a 65-kda protein, and transcripts from this gene are readily detected. rck1 has been mapped to the l arm of chromosome vii, and rck2 to chromosome xii. disruption of the ...19948112585
induction of pseudohyphal growth by overexpression of phd1, a saccharomyces cerevisiae gene related to transcriptional regulators of fungal development.when starved for nitrogen, mata/mat alpha cells of the budding yeast saccharomyces cerevisiae undergo a dimorphic transition to pseudohyphal growth. a visual genetic screen, called phd (pseudohyphal determinant), for s. cerevisiae pseudohyphal growth mutants was developed. the phd screen was used to identify seven s. cerevisiae genes that when overexpressed in mata/mat alpha cells growing on nitrogen starvation medium cause precocious and unusually vigorous pseudohyphal growth. phd1, a gene whos ...19948114741
fungal catabolic gene regulation: molecular genetic analysis of the amds gene of aspergillus nidulans.aspergillus nidulans is an excellent experimental organism for the study of gene regulation. genetic and molecular analyses of trans-acting and cis-acting mutations have revealed a complex pattern of regulation involving multiple independent controls. expression of the amds gene is regulated by the facb and amda genes which encode positively acting regulatory proteins mediating a major and a minor form of acetate induction respectively. the product of the amdr gene mediates omega amino acid indu ...19938119589
identification of substrate specificity determinants for the cell cycle-regulated nima protein kinase.nima is a cell cycle-regulated protein kinase required for the g2/m transition in the filamentous fungus aspergillus nidulans. previous biochemical characterization of the recombinant enzyme indicated that nima is a protein serine/threonine specific kinase with beta-casein being the best substrate from the many proteins and peptides tested (lu, k.p., osmani, s.a., and means, a.r. (1993) j. biol. chem. 268, 8769-8776). however, substrate specificity or physiologically relevant substrates for nima ...19948120013
an "instant gene bank" method for heterologous gene cloning: complementation of two aspergillus nidulans mutants with gaeumannomyces graminis dna.we present a novel technique for gene cloning by complementation of mutations in aspergillus nidulans with dna from a heterologous organism, gaeumannomyces graminis. this technique bypasses the time-consuming and difficult construction of gene libraries, making it both rapid and simple. the method relies on recombination between a fungal replicating vector phelp1 and linear g. graminis genomic dna during co-transformation. we were able to complement two out of seven a. nidulans mutants tested an ...19948121400
an 'instant gene bank' method for gene cloning by mutant complementation.we describe a new method of gene cloning by complementation of mutant alleles which obviates the need for construction of a gene library in a plasmid vector in vitro and its amplification in escherichia coli. the method involves simultaneous transformation of mutant strains of the fungus aspergillus nidulans with (i) fragmented chromosomal dna from a donor species and (ii) dna of a plasmid without a selectable marker gene, but with a fungal origin of dna replication ('helper plasmid'). transform ...19948121403
regulation of the expression of the isocitrate lyase gene (acud) of aspergillus nidulans.analysis of the promoter region of the acetate-induced isocitrate lyase gene (acud) of aspergillus nidulans is described. transcription start sites were detected at positions -163, -170 and approximately -281 upstream of the atg. transcription analysis showed that the acud gene is transcribed during growth on acetate but not on hexoses or glycerol. expression of the acud gene was studied under inducing and repressing conditions in cre+, crea, creb and crec mutant strains, showing that the crea(d ...19948121406
alpha-l-arabinofuranosidase production by aspergillus nidulans.the effects of some physico-chemical parameters on production of extracellular alpha-l-arabinofuranosidase by aspergillus nidulans were examined. highest levels of alpha-l-arabinofuranosidase were generated with cultures grown on 1% (w/v) purified beet pulp arabinan at 30 degrees c and at an initial ph of 7.0. the enzyme was shown to be very sensitive to the action of proteases. zymogram overlay of a protein profile obtained by sds-page revealed the occurrence of a band (m(r) 36,000) exhibiting ...19948125239
at least three genes are responsible for benomyl-resistance in metarhizium anisopliae.four benomyl-resistant mutants isolated from metarhizium anisopliae were 10 to 500 times more resistant than the original mt strain. the resistance markers analysed in three of these mutants were due to three different mutations and no additive effect of these genes was observed in double mutants. the four mutants presented normal conidiation in the presence or absence of benomyl and no sensitivity or resistance to temperature. probably m. anisopliae has a mechanism of benomyl resistance differi ...19948127229
cytoplasmic dynein is involved in nuclear migration in aspergillus nidulans.nuclear migration plays an important role in the growth and development of many organisms including the multinuclear fungus aspergillus nidulans. we have identified four genes, nuda, nudc, nudf, and nudg, in which temperature-sensitive mutations affect nuclear distribution. in this report, we describe the cloning of the nuda gene by complementation of the mutant phenotype by using a chromosome viii-specific cosmid library. a genomic fragment of nuda hybridized to an mrna of approximately 14 kb. ...19948134356
the alcohol dehydrogenase gene adh1 is induced in aspergillus flavus grown on medium conducive to aflatoxin aspergillus flavus cdna library was screened by differential hybridization to isolate clones corresponding to genes that are actively transcribed under culture conditions conducive to aflatoxin biosynthesis. one clone with a 1.28-kb insert was isolated, and its nucleotide sequence was determined. the nucleotide sequence of this clone had 75% dna identity to those of the alcohol dehydrogenase genes from aspergillus nidulans, and the putative polypeptide translated from the cdna sequence had 82 ...19948135521
the aspergillus nidulans abaa gene encodes a transcriptional activator that acts as a genetic switch to control development.the aspergillus nidulans abaa gene encodes a protein containing an atts dna-binding motif and is required for the terminal stages of conidiophore development. results from gel mobility shift and protection, missing-contact, and interference footprint assays showed that abaa binds to the sequence 5'-cattcy-3', where y is a pyrimidine, making both major- and minor-groove contacts. multiple abaa binding sites are present in the cis-acting regulatory regions of several developmentally controlled str ...19948139553
sulfur amino acid metabolism and its regulation in fungi: studies with aspergillus nidulans. 19938140816
in vitro binding of the two-finger repressor crea to several consensus and non-consensus sites at the ipna upstream region is context dependent.the two zinc-fingers of the aspergillus nidulans repressor crea recognize the consensus hexanucleotide 5'-syggrg-3'. we have determined all the crea binding sites in a approximately 2 kb region upstream the ipna gene. our analysis shows that (i) crea binds to certain consensus sites in a context-dependent manner; (ii) five non-consensus 6-bp sequences are also recognized by crea; this non-canonical binding correlates with the presence of a second, neighbouring crea binding site, suggesting that ...19948143847
identification and characterization of aspergillus nidulans mutants defective in cytokinesis.filamentous fungi undergo cytokinesis by forming crosswalls termed septa. here, we describe the genetic and physiological controls governing septation in aspergillus nidulans. germinating conidia do not form septa until the completion of their third nuclear division. the first septum is invariantly positioned at the basal end of the germ tube. block-and-release experiments of nuclear division with benomyl or hydroxyurea, and analysis of various nuclear division mutants demonstrated that septum f ...19948150280
homologs of the yeast neck filament associated genes: isolation and sequence analysis of candida albicans cdc3 and cdc10.morphogenesis in the yeast saccharomyces cerevisiae consists primarily of bud formation. certain cell division cycle (cdc) genes, cdc3, cdc10, cdc11, cdc12, are known to be involved in events critical to the pattern of bud growth and the completion of cytokinesis. their products are associated with the formation of a ring of neck filaments that forms at the region of the mother cell-bud junction during mitosis. morphogenesis in candida albicans, a major fungal pathogen of humans, consists of bot ...19948152419
homology at the amino acid level between plant phytochromes and a regulator of asexual sporulation in emericella (= aspergillus) nidulans.protein sequence comparison between the n-terminal regions of the brla (bristle a) protein of the ascomycete fungus aspergillus nidulans and a number of plant phytochromes has demonstrated a moderate level of sequence similarity. the region of similarity corresponds to the phytochrome domains believed to be responsible for photoreception and which undergo light-induced conformational changes, although a putative chromophore-binding site is not evident. over 22% of residues are conserved and 24% ...19948165242
microtubule organizing centers and gamma-tubulin.the polar assembly of cellular microtubules is organized by microtubule organizing centers (mtocs). eukaryotic cells across different species, and different cell types within single species, have morphologically diverse mtocs, which have the common function of organizing microtubule arrays by initiating microtubule assembly and anchoring microtubules by their slow-growing 'minus' ends, thus ensuring that the rapidly growing 'plus' ends extend distally. the past few years have witnessed a variety ...19948167026
characterization of a 3-dehydroquinase gene from actinobacillus pleuropneumoniae with homology to the eukaryotic genes qa-2 and qute.a gene was cloned from actinobacillus pleuropneumoniae strain 4074 by complementation of an arod strain of escherichia coli. the e. coli gene arod codes for a 3-dehydroquinase enzyme of type i, active in the aromatic biosynthesis pathway. the a. pleuropneumoniae gene, termed aroq, displays no base or amino acid sequence homology to arod of e. coli. it is instead homologous to the qute and qa-2 genes, respectively of aspergillus nidulans and neurospora crassa. these genes code for 3-dehydroquinas ...19948170389
identification of nitrate transporter genes in chlamydomonas reinhardtii.the chlamydomonas reinhardtii nar-2, nar-3, and nar-4 genes, which are within a nitrate-regulated gene cluster containing the nitrate reductase structural gene nit-1, have been related to nitrate transport. mutant strains defective in nitrate transport and having an active nitrate reductase have been genetically constructed. their nitrate non-utilizing phenotype has been directly complemented by transformation using the pco-5 plasmid which carries the nar-2, nar-3, and nar-4 clustered genes. int ...19948180624
expression of the noncatalytic domain of the nima kinase causes a g2 arrest in aspergillus nidulans.temperature-sensitive mutation of the nima gene of aspergillus nidulans causes a reversible g2 arrest, whereas overexpression of nima causes premature entry into mitosis from which the cells cannot exit. the nima gene encodes a ser/thr-specific protein kinase (nima) which contains an extended cooh-terminal noncatalytic domain. to evaluate the role of this enzyme in nuclear division control, we introduced various mutant nima cdnas under the control of the inducible alcohol dehydrogenase gene prom ...19948187763
variability of aspergillus nidulans antigens with media and time and temperature of growth.the influence of culture medium and time and temperature of growth on the appearance of aspergillus nidulans antigens was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, followed by silver staining or western blot (immunoblot), of the proteins present in total cellular extracts or culture supernatants. samples in the exponential, deceleration, and stationary growth phases were selected by biochemical, morphological, and ultrastructural criteria. protein and antigen patte ...19948188355
expression of the 3-phosphoglycerate kinase gene (pgka) of penicillium chrysogenum.the sequence of the penicillium chrysogenum pgka gene promoter was determined up to 952 nucleotides (nt) 5' to the major transcriptional start point (position +1), and contains a 38 bp pyrimidine-rich region within which transcription initiates at this and two minor sites (-11, -23). a 21 bp segment (-99 to -79) closely matches a region which is essential for the expression of the aspergillus nidulans pgka gene. a further region was found with similarity to sequences in other a. nidulans promote ...19948190080
the avr9 race-specific elicitor of cladosporium fulvum is processed by endogenous and plant proteases.the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum encodes a race-specific peptide elicitor that induces a hypersensitive response in tomato plants carrying the complementary resistance gene cf9. the avr9 gene is highly expressed when c. fulvum is growing in the plant and the elicitor accumulates in infected leaves as a 28-amino acid (aa) peptide. in c. fulvum grown in vitro, the peptide elicitor is not produced in detectable amounts. to produce significant amounts of the ...19938208859
heat resistance of fungi from soil.the survival of fungi from soil samples has been investigated after exposure to temperatures of 60, 70, 80 and 90 degrees c in sabouraud agar. the least resistant fungi surviving 60 degrees c for 60 min were the aspergillus (a.) niger group, chaetomium spp, penicillium spp, and scytalidium lignicola. none of these survived 70 degrees c for 10 min. the next group surviving 70 degrees c for 60 min included the a. glaucus group, byssochlamys nivea, dichotomomyces cejpii, gelasinospora spp, rhizocto ...19938217516
preliminary studies of two active site mutants of galactose oxidase. 19938224464
galactose oxidase: molecular analysis and mutagenesis studies. 19938224504
characterisation, cloning and integrative properties of the gene encoding urate oxidase in aspergillus nidulans.a number of mutations have been obtained which define the structural gene (uaz) coding for urate oxidase in linkage group i of aspergillus nidulans. this gene has been cloned by transformation of a uaz- null mutant. a chromosome i/viii translocation which splits the gene has been defined both genetically and physically. all known mutations are contained in a 1-kb fragment, itself contained in the probe which recognizes a 1.2-kb inducible message. plasmids carrying uaz show a strict bias towards ...19938224862
heterologous protein secretion directed by a repressible acid phosphatase system of aspergillus niger.a new expression-secretion system of aspergillus niger which directs the secretion of heterologous proteins is described. the promoter and signal peptide-encoding region of the phosphate-repressible apha gene of a. niger, when fused to the coding region of the human interferon alpha 2 (hifn alpha 2)-encoding gene (hifn alpha 2), drives the expression of this gene and the secretion of the hifn alpha 2 protein. synthesis of hifn alpha 2 in either a. niger or a. nidulans transformants carrying thes ...19938224863
a novel phage lambda replacement cre-lox vector that has automatic subcloning capabilities.we have developed a novel phage lambda replacement cloning vector, lambda pan. lambda pan allows one to automatically subclone the insert as a plasmid using the cre-loxp site-specific recombination system. this eliminates the need to subclone insert fragments and permits the rapid structural analysis of insert dna. lambda pan is similar to other phage lambda replacement vectors taking inserts ranging in size from 5 to 19 kb. we have placed the pyrg gene of aspergillus nidulans on the vector as a ...19938224901
sequence and regulation of the uapa gene encoding a uric acid-xanthine permease in the fungus aspergillus nidulans.the nucleotide sequence of the uapa gene, coding for the uric acid-xanthine permease of aspergillus nidulans, has been determined. the predicted uapa gene product comprises 595 amino acids (m(r) 63,365); it is a highly hydrophobic protein with 12-14 putative transmembrane segments and shows no striking similarity to any other membrane protein of either prokaryotes or eukaryotes, except for a short highly hydrophobic amino acid sequence conserved in a number of different permeases. the presence o ...19938226862
sequence, regulation, and mutational analysis of the gene encoding urate oxidase in aspergillus nidulans.the uaz gene of aspergillus nidulans codes for a protein of 301 amino acids. the open reading frame is interrupted by two introns. a comparison with the open reading frames of 10 other urate oxidases reveals a number of scattered universally conserved residues and four clusters of high similarity. two of these are of unknown function, and the other two are the putative sites for copper binding and the signal sequence for peroxisomal entry, respectively. this comparison also reveals that there ar ...19938226863
molecular characterization of a fungal secondary metabolism promoter: transcription of the aspergillus nidulans isopenicillin n synthetase gene is modulated by upstream negative elements.the aspergillus nidulans ipns gene, encoding isopenicillin n synthetase, is a secondary metabolism gene. it is contiguous to, but divergently transcribed from, the acvs gene at the penicillin gene cluster. the untranslated region between both orfs is 872bp long. here we present the physical and functional characterization of the ipns transcriptional unit. transcriptional start point (tsp) mapping reveals heterogeneity at the 5'-end of the mrna, with a major start at -106 relative to the initiati ...19938231816
brushing up on bristles: complex genes and morphogenesis in molds. 19938236455
arabinan degrading enzymes from aspergillus nidulans: induction and purification.the presence in aspergillus nidulans of two enzymes related to the aspergillus niger endo-arabinase and alpha-l-arabinofuranosidase b has been established using antibodies against the purified a. niger enzymes. moreover, the absence of an equivalent in a. nidulans to the alpha-l-arabinofuranosidase a of a. niger has been confirmed both at the protein and at the dna level. both a. nidulans arabinases have been purified and physico-chemically and kinetically characterized. they have a much higher ...19938243977
comparative studies on o-acetylhomoserine sulfhydrylase: physiological role and characterization of the aspergillus nidulans enzyme.o-acetylhomoserine sulfhydrylase (oah shlase) from aspergillus nidulans is an oligomeric protein with a broad substrate specificity with regard to sulfhydryl compounds. as its saccharomyces cerevisiae counterpart the enzyme also reacts with o-acetylserine and is inhibited by carbonyl reagents but not by antiserum raised against the yeast enzyme. in contrast to saccharomyces cerevisiae the enzyme is not essential for aspergillus nidulans as indicated by the completely prototrophic phenotype of oa ...19938249501
regulation of sulfur and nitrogen metabolism in filamentous the filamentous fungi, n. crassa and a. nidulans, complex regulatory circuits control nitrogen metabolism and sulfur metabolism. the expression of entire sets of unlinked structural genes that encode metabolic enzymes is repressed when favored sulfur or nitrogen sources are available. these structural genes are coregulated by global positive-acting regulatory proteins and often are also controlled by metabolic inducers and pathway-specific regulatory proteins. the recent isolation of regulato ...19938257101
characterization of the 3-dehydroquinase domain of the pentafunctional arom protein, and the quinate dehydrogenase from aspergillus nidulans, and the overproduction of the type ii 3-dehydroquinase from neurospora crassa.the arom protein of aspergillus nidulans is a multidomain pentafunctional polypeptide that is active as a dimer and catalyses steps 2-6 in the prechorismate section of the shikimate pathway. the three c-terminal domains (including the type i 3-dehydroquinase) of the arom protein are homologous with the qutr-encoded qutr protein that represses transcription of the eight genes comprising the quinic acid utilization (qut) gene cluster, and the two n-terminal domains are homologous with the quta-enc ...19938257437
kinetic studies of nitrite uptake by aspergillus nidulans.1. in the filamentous mold aspergillus nidulans, net nitrite uptake is inducible by nitrate and nitrite, is probably different from the nitrate uptake system and is partially repressed by ammonium. 2. the concentration dependence of net nitrite uptake by the bia1 faca303 strain of a. nidulans shows a saturation kinetics with an apparent km value of 0.64 mm. 3. strains of a. nidulans carrying the niha1 and niha1 chla14 mutations considerably reduced the affinity of the nitrite uptake system for t ...19938257915
survey of mycoflora and mycotoxins in egyptian soybean seeds.after four months in commercial storage, 100 soybean samples from different places of egyptian governorates were assayed for filamentous fungal growth at two incubation temperatures (28 and 45 degrees c). 73 species and 8 varieties belonging to 32 genera were isolated by the dilution plate method. at 28 degrees c, the common species were aspergillus flavus, a. fumigatus, a. niger and a. alutaceus, followed by a. terreus, penicillium chrysogenum, p. citrinum, mucor hiemalis, m. racemosus, emerice ...19938271157
identification of 21 novel human protein kinases, including 3 members of a family related to the cell cycle regulator nima of aspergillus nidulans.the nima gene encodes a protein-serine/threonine kinase that is required along with the p34cdc2 kinase for mitosis in aspergillus nidulans. we have searched for human protein kinases that are related to the nima protein kinase using the polymerase chain reaction. different pairs of degenerate oligonucleotides specific for conserved amino acid motifs in the catalytic domain of nima were used as primers in the polymerase chain reaction to amplify partial complementary dnas (cdnas) of protein kinas ...19938274451
purification and characterization of glucose-6-phosphate dehydrogenase from aspergillus niger and aspergillus nidulans.glucose-6-phosphate dehydrogenase (g6pd; d-glucose 6-phosphate:nadp+ oxidoreductase, ec has been purified from aspergillus nidulans and aspergillus niger by a combination of affinity and anion exchange chromatography. a 500-1000-fold purification was obtained and the final enzyme preparations were shown to be pure but not homogeneous. for both fungi the purified enzyme preparation gave two bands on native and denaturing gels. the catalytically active form is a multimer. the molecular m ...19938277259
cloning and characterisation of the cytochrome c gene of aspergillus nidulans.the cytochrome c gene (cyca) of the filamentous fungus aspergillus nidulans has been isolated and sequenced. the gene is present in a single copy per haploid genome and encodes a polypeptide of 112 amino acid residues. the nucleotide sequence of the a. nidulans cyca gene shows 87% identity to the dna sequence of the neurospora crassa cytochrome c gene, and approximately 72% identity to the sequence of the saccharomyces cerevisiae iso-1-cytochrome c gene (cyc1). the s. cerevisiae cyc1 gene was us ...19948277943
relationship between zinc content and dna-binding activity of the dna-binding motif of the transcription factor alcr in aspergillus nidulans.the transcription factor alcr of the ethanol utilisation pathway in aspergillus nidulans contains a zinc binuclear motif (cysx2cysx6cysx16cysx2cysx6cys), within the dna-binding domain located in the n-terminal region of the alcr protein. specific targets have been localised in the promoter of the alcr gene, involved in the autoregulation process, and in the promoter of the structural gene alca (encoding alcohol dehydrogenase i), which is also under the control of alcr. the dna-binding domain has ...19948277945
analysis of the regulation of penicillin biosynthesis in aspergillus nidulans by targeted disruption of the acva analyse the regulation of the biosynthesis of the secondary metabolite penicillin in aspergillus nidulans, a strain with an inactivated acva gene produced by targeted disruption was used. acva encodes delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase (acvs), which catalyses the first step in the penicillin biosynthetic pathway. to study the effect of the inactivated acva gene on the expression of acva and the second gene, ipna, which encodes isopenicillin n synthase (ipns), a. nidul ...19948277946
the macronuclear gamma-tubulin-encoding gene of euplotes octocarinatus contains two introns and an in-frame tga.the gamma-tubulin (gamma-tub)-encoding gene (gamma-tub) of euplotes octocarinatus was amplified from macronuclear dna with the help of the polymerase chain reaction (pcr) and sequenced. the polypeptide deduced from the gene consists of 462 amino acids (aa). it shares 61% aa identity with the aspergillus nidulans gamma-tub. the gene contains an in-frame tga codon and two small pre-mrna introns (36 and 26 bp). we suggest that the tga, like tga codons in the pheromone-encoding genes of e. octocarin ...19938294024
genesis of eukaryotic transcriptional activator and repressor proteins by splitting a multidomain anabolic enzyme.the genes necessary for the correctly regulated catabolism of quinate in aspergillus nidulans and neurospora crassa are controlled at the level of transcription by a dna-binding activator protein and a repressor protein that directly interact with one another. the repressor protein is homologous throughout its length with the three c-terminal domains of a pentafunctional enzyme catalysing five consecutive steps in the related anabolic shikimate pathway. we now report that the activator protein i ...19938294040
molecular organization of the escherichia coli gab cluster: nucleotide sequence of the structural genes gabd and gabp and expression of the gaba permease gene.we have determined the nucleotide sequences of two structural genes of the escherichia coli gab cluster, which encodes the enzymes of the 4-aminobutyrate degradation pathway: gabd, coding for succinic semialdehyde dehydrogenase (ssdh, ec and gabp, coding for the 4-aminobutyrate (gaba) transport carrier (gaba permease). we have previously reported the nucleotide sequence of the third structural gene of the cluster, gabt, coding for glutamate: succinic semialdehyde transaminase (ec 2.6.1 ...19938297211
induction of glucose oxidase, catalase, and lactonase in aspergillus niger.the induction of glucose oxidase, catalase, and lactonase activities was studied both in wild-type and in glucose oxidase regulatory and structural mutants of aspergillus niger. the structural gene for glucose oxidase was isolated and used for northern analysis and in transformation experiments using various gox mutations. wild-type phenotype could be restored in the glucose oxidase-negative mutant (goxc) by transformation with the structural gene. we conclude, therefore, that the goxc marker wh ...19938299156
co-transformation with autonomously-replicating helper plasmids facilitates gene cloning from an aspergillus nidulans gene library.autonomously-replicating, marker-less "helper" plasmids were added to transformations of aspergillus nidulans with plasmids which normally transform by chromosomal integration. this resulted in as much as a 200-fold increase in transformation efficiency. recovery of autonomously-replicating plasmid co-integrates indicated that co-transformation involves recombination between integrating and helper plasmids, which occurs at a high frequency. increasing dna sequence-homology between pairs of plasm ...19938299174
cloning and characterization of the abfb gene coding for the major alpha-l-arabinofuranosidase (abf b) of aspergillus niger.based on amino-acid sequence data from aspergillus niger alpha-l-arabinofuranosidase b (abf b), and cyanogen bromide fragments derived thereof, deoxyoligonucleotide mixtures were designed to be employed as primers in a polymerase chain reaction (pcr) on a. niger genomic dna. this resulted in amplification of three related pcr products. the abfb gene encoding abf b was isolated from a genomic library using such an amplification product as a probe. a 5.1-kb bamhi fragment was subcloned to result i ...19938299175
two different, adjacent and divergent zinc finger binding sites are necessary for crea-mediated carbon catabolite repression in the proline gene cluster of aspergillus nidulans.crea is the negative regulator mediating carbon catabolism repression in aspergillus nidulans. we have determined all the sites in the dna region between the prnd and prnb genes of the proline degradation cluster of this organism which are able to bind a fusion protein containing the zinc finger domain of crea. the consensus sequence derived for crea binding is 5'-syggrg-3', but not all possible sites derived from this consensus do in fact bind. the binding of at least some sequences of the form ...19948313886
evidence for a multi-allelic heterokaryon incompatibility (het) locus detected by hybridization among three heterokaryon-compatibility (h-c) groups of aspergillus nidulans.a strain of heterokaryon-compatibility (h-c) group a was crossed sexually to strains of h-cb and h-cgl of aspergillus nidulans. a back-crossing programme established that there were seven hetero-allelic heterokaryon compatibility (het) genes controlling somatic incompatibility between strains of h-ca and h-cb. a similar back-crossing programme between strains of h-ca and h-cgl confirmed that these two groups differ at six het loci. previous work has shown that h-cb differs from h-cgl at two het ...19938314715
spatial and temporal controls of the aspergillus brla developmental regulatory gene.the aspergillus nidulans brla gene encodes a transcriptional regulator of central importance in controlling conidiophore development. i have determined the effects of mutations in other developmental regulatory genes on expression of a brla-lacz fusion gene. deletion of brla reduced beta-galactosidase levels by half and led to delocalization of enzyme accumulation. the meda26 and abaa2 developmental mutations led to overexpression of the fusion gene without altering spatial specificity. in contr ...19938316075
choline: its role in the growth of filamentous fungi and the regulation of mycelial morphology.choline is an essential metabolite for the growth of filamentous fungi. it occurs most notably as a component of the major membrane phospholipid, phosphatidyl choline (lecithin), and fulfills a major role in sulphate metabolism in the form of choline-o-sulphate in many species. choline is usually synthesised endogenously, but exogenous choline can also be taken up, either to compensate for metabolic deficiencies in choline-requiring mutants such as those of aspergillus nidulans and neurospora cr ...19938318261
isolation and nucleotide sequence of the 5-aminolevulinate synthase gene from aspergillus nidulans.the structural gene for 5-aminolevulinate (ala) synthase has been cloned and sequenced from the filamentous fungus aspergillus nidulans using an oligonucleotide probe based on a highly conserved-amino-acid sequence found in ala synthase genes of a wide range of species. the cloned gene, hema, has a 5' untranslated mrna of 92 nucleotides (nt) and one intron (64 nt). the deduced protein sequence (648 amino acids) shows 64% identity to the yeast ala synthase in the c-terminal region of 453 amino ac ...19938319309
complement binding to aspergillus conidia correlates with pathogenicity.complement has significant effects on the phagocytosis of aspergillus organisms. we examined the amount and type of complement component c3 bound to the resting conidia of 29 isolates from nine aspergillus species. the highly pathogenic species a. fumigatus and a. flavus bound fewer c3 molecules per unit of conidial surface area than did the less pathogenic species a. glaucus, a. nidulans, a. niger, a. ochraceus, a. terreus, a. versicolor, and a. wentii, as determined by quantitative flow cytome ...19938320488
the isolation of mutagen-sensitive nuv mutants of aspergillus nidulans and their effects on mitotic recombination.more than 200 mutants of aspergillus nidulans were isolated as hypersensitive to the monofunctional alkylating agent mnng and/or uv-irradiation (designated nuv mutants). of these, 23 were selected for further characterization. all were markedly hypersensitive to both mnng and the quasi-uv-mimetic mutagen 4-nqo. the hypersensitive phenotype of each mutant was shown to result from mutation of a single gene. the nuv mutants exhibited a diverse range of growth responses on solid media containing var ...19938325481
either alpha-tubulin isogene product is sufficient for microtubule function during all stages of growth and differentiation in aspergillus nidulans.the filamentous fungus aspergillus nidulans has two genes encoding alpha-tubulin, tuba and tubb, which are differentially required at distinct stages during the life cycle. the tuba gene is required during vegetative growth for mitosis and nuclear migration (b. r. oakley, c. e. oakley, and j. e. rinehart, mol. gen. genet. 208:135-144, 1987; p. doshi, c. a. bossie, j. h. doonan, g. s. may, and n. r. morris, mol. gen. genet. 225:129-141, 1991). the tubb gene is not required for any detectable aspe ...19938336695
uvsi mutants defective in uv mutagenesis define a fourth epistatic group of uvs genes in aspergillus.three uv-sensitive mutations of a. nidulans, uvsi, uvsj and uvsa, were tested for epistatic relationships with members of the previously established groups, here called the "uvsf", "uvsc", and "uvsb" groups. uvsi mutants are defective for spontaneous and induced reversion of certain point mutations and differ also for other properties from previously analyzed uvs types. they are very sensitive to the killing effects of uv-light and 4-nqo (4-nitro-quinoline-n-oxide) but not to mms (methylmethane ...19938358834
the aspergillus niger carbon catabolite repressor encoding gene, order to undertake a comparative analysis of carbon catabolite repression in two aspergillus species, the crea gene has been isolated from a. niger by cross hybridization, using the cloned a. nidulans gene. the a. niger gene has been shown to be functional in a. nidulans by heterologous complementation of the crea204 mutation of a. nidulans. overall, the genes show 90% sequence similarity (82% identity) at the amino acid (aa) level. there were some striking similarities between the aa sequenc ...19938359691
characterization of the pyruvate kinase-encoding gene (pki1) of trichoderma reesei.the pyruvate kinase-encoding gene (pki1) from trichoderma reesei was isolated by hybridization to the corresponding aspergillus nidulans pkia gene. the 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. the coding sequence contains a single intron of 246 nt at a position identical to that of intron e in the a. nidulans gene. the pki protein shows extensive homology to the pkis of a. nidulans and a. niger (67%) and saccharomyces cerevisiae (59%). the 5' non-co ...19938359694
the gamma-tubulin gene of the malaria parasite plasmodium screening of cdna and genomic libraries of plasmodium falciparum with a dna probe derived from the cognate beta-tubulin gene, gene pf gamma tub has been identified that codes for gamma-tubulin, a newly discovered member of the tubulin superfamily that is indispensible for nuclear division and microtubule assembly [12]. gene pf gamma tub is not interrupted by introns and only present as a single-copy in the parasite genome. its encoded amino acid sequence (452 amino acids; m(r) 50,560) has a 6 ...19938366893
the nia gene of fusarium oxysporum: isolation, sequence and development of a homologous transformation system.the fusarium oxysporum gene nia, encoding nitrate reductase (nr), was isolated from a cosmid library by direct complementation of an f. oxysporum nia- mutant. the gene specifies a protein of 905 amino acids and contains a 57-bp intron. comparison of the deduced aa sequence with nr of other fungi revealed a high degree of similarity and conservation in the intron position. the cloned nia made it possible to develop the first homologous transformation system for this fungus. transformation frequen ...19938370541
analysis of heterokaryon incompatibility between heterokaryon-compatibility (h-c) groups r and gl provides evidence that at least eight het loci control somatic incompatibility in aspergillus nidulans.protoplast fusion was used to hybridize strains 99-6 (h-cr) and 7-141 (h-cgl) in the birmingham collection of aspergillus nidulans. a sparsely conidiating, brown-pigmented diploid strain (ma7) was isolated. inocula from ma7 were haploidized on medium containing benlate and a haploid progeny sample collected. heterokaryon compatibility testing of selected progeny strains assayed each linkage group in turn and established that h-cr and h-cgl were hetero-allelic for heterokaryon incompatibility (he ...19938371120
mutation in the bimd gene of aspergillus nidulans confers a conditional mitotic block and sensitivity to dna damaging agents.mutation in the bimd gene of aspergillus nidulans results in a mitotic block in anaphase characterized by a defective mitosis. mutation in bimd also confers, at temperatures permissive for the mitotic arrest phenotype, an increased sensitivity to dna damaging agents, including methyl methanesulfonate and ultraviolet light. in order to better understand the relationship between dna damage and mitotic progression, we cloned the bimd gene from aspergillus. a cosmid containing the bimd gene was iden ...19938375649
quantitative structure-activity relationship models correctly predict the toxic and aneuploidizing properties of six halogenated methanes in aspergillus a previous study, the relationships between the chemical structure and the ability of 35 chlorinated aliphatic hydrocarbons to induce aneuploidy and toxicity in aspergillus nidulans were analyzed. quantitative structure-activity relationships (qsar) were defined for each of the biological activities under study: arr (the dose able to block mitotic growth), d37 (the dose with 37% of survival) and lec (the lowest efficient concentration in aneuploidy induction). in this study, these qsar equati ...19938377647
development of a transformation system for the filamentous, ml-236b (compactin)--producing fungus penicillium citrinum.we present here the first report of a transformation system developed for the filamentous, ml-236b (compactin)-producing fungus penicillium citrinum. hygromycin b-resistant colonies were obtained after treatment of protoplasts with a vector containing an escherichia coli hygromycin b phosphotransferase gene fused to a 3-phosphoglycerate kinase promoter from aspergillus nidulans. the transformation rate was 194 transformants per microgram circular dna per 4 x 10(5) viable protoplasts under optimi ...19938381335
the molecular biology of the pentafunctional arom protein. 19938383607
overproduction of, and interaction within, bifunctional domains from the amino- and carboxy-termini of the pentafunctional arom protein of aspergillus nidulans.the pentafunctional arom protein in aspergillus nidulans and other fungi catalyses five consecutive enzymatic steps leading to the production of 5-enolpyruvylshikimate 3-phosphate (epsp) in the shikimate pathway. the arom protein has five separate enzymatic domains that have previously been shown to display a range of abilities to fold and function in isolation as monofunctional enzymes. in this communication, we report (1) the stable overproduction of a bifunctional protein containing the 3-deh ...19938393515
ph regulation is a major determinant in expression of a fungal penicillin biosynthetic gene.transcription of the ipna gene encoding isopenicillin n synthetase, an enzyme of secondary metabolism, is under the control of the ph regulatory system in the fungus aspergillus nidulans. external alkaline ph or mutations in pacc, the wide domain regulatory gene which mediates ph regulation, override carbon regulation of ipna transcript levels, resulting in elevation of the levels of this message in sucrose broth. strains carrying these mutations, which mimic growth at alkaline ph, produce highe ...19938404862
purification and molecular properties of an alpha-galactosidase synthesized and secreted by aspergillus nidulans.alpha-galactosidases from mycelial extract and culture filtrate of aspergillus nidulans have been purified to homogeneity and utilised to obtain polyclonal antibodies anti-alpha-galactosidase. the enzymatic characteristics and the cross reactivity of the antibodies suggest that alpha-galactosidases isolated from the two sources were the same enzyme. thus, a. nidulans synthesized and secreted only one enzymatic form of alpha-galactosidase which is a multimeric enzyme of 370 kda composed of four m ...19938405947
biochemical characterization and molecular genetics of nine mutants of penicillium chrysogenum impaired in penicillin biosynthesis.nine mutants of penicillium chrysogenum (npe1 to npe8 and npe10) impaired in penicillin biosynthesis were screened after nitrosoguanidine mutation. mutants npe1, npe4, npe5, npe6, npe7, npe8, and npe10 failed to synthesize significant levels of penicillin, whereas strains npe2 and npe3 synthesized about 20% of the penicillin level produced by the parental strain. mutants npe5 and npe10 did not show alpha-aminoadipylcysteinyl-valine (acv) synthetase activity in vitro and did not form acv in vivo. ...19938416976
functional redundancy in mitotic force generation. 19938416980
suppression of the bimc4 mitotic spindle defect by deletion of klpa, a gene encoding a kar3-related kinesin-like protein in aspergillus investigate the relationship between structure and function of kinesin-like proteins, we have identified by polymerase chain reaction (pcr) a new kinesin-like protein in the filamentous fungus aspergillus nidulans, which we have designated klpa. dna sequence analysis showed that the predicted klpa protein contains a cooh terminal kinesin-like motor domain. despite the structural similarity of klpa to the kar3 and ncd kinesin-like proteins of saccharomyces cerevisiae and drosophila melanogaste ...19938416986
identification of aspergillus brla response elements (bres) by genetic selection in yeast.the brla gene of aspergillus nidulans plays a central role in controlling conidiophore development. to test the hypothesis that brla encodes a transcriptional regulator and to identify sites of interaction for the brla polypeptide, we expressed brla in saccharomyces cerevisiae (yeast) strains containing aspergillus dna sequences inserted upstream of a minimal yeast promoter fused to the escherichia coli lacz gene. initially, a dna fragment from the promoter region of the developmentally regulate ...19938417986
genetic maps of eight linkage groups of aspergillus niger based on mitotic mapping.this paper provides a genetic map of aspergillus niger. at present 84 markers have been assigned to eight linkage groups. the chromosomal location of 60 markers is presented in this paper. the allocation of markers is based on recombination due to mitotic crossing over. various methods for selection and analysis of homozygous recombinants were applied, using colour, auxotrophic and resistance markers. in addition, transformants carrying the heterologous aspergillus nidulans gene coding for aceta ...19938428383
disruption of the 3' phosphoglycerate kinase (pgk) gene in aspergillus nidulans.we report the isolation of a pgk- mutant strain of aspergillus nidulans by means of a gene disruption strategy, and demonstrate that the pgk gene is located on chromosome viii. the pgk- mutant conidiates poorly, will only grow on media supplemented with both a glycolytic and a gluconeogenic carbon source, and is inhibited by hexoses.19938431952
cloning and sequencing of the 3-phosphoglycerate kinase (pgk) gene from penicillium citrinum and its application to heterologous gene expression.the gene coding for 3-phosphoglycerate kinase (pgk) in ml-236b (compactin)-producing penicillium citrinum was isolated from the recombinant phage lambda library using the corresponding aspergillus nidulans pgk gene as a probe. the p. citrinum pgk gene has an open reading frame of 1,254 bp, encoding a protein of 417 amino acids with a predicted molecular weight of 44,079 daltons. the position of the two introns, 59 and 60 bp respectively, was deduced from an homology comparison with the sequence ...19938431954
bima, a tpr-containing protein required for mitosis, localizes to the spindle pole body in aspergillus nidulans.the aspergillus nidulans bima gene is required for mitosis. loss of function mutations in bima cause cells to arrest growth with condensed chromatin and a short, metaphaselike mitotic spindle. bima is a member of a gene family defined by a repeated motif called the tetratrico peptide repeat (tpr), which is found in genes from bacteria, yeast and insects. several yeast tpr genes are also required for mitosis, including saccharomyces cerevisiae cdc27 and schizosaccharomyces pombe nuc2+, which appe ...19938432735
c-terminal truncation of the transcriptional activator encoded by area in aspergillus nidulans results in both loss-of-function and gain-of-function phenotypes.mutations truncating as many as 143 c-terminal residues from the transcriptional activator encoded by the area gene, mediating nitrogen metabolite repression in aspergillus nidulans, do not significantly reduce the ability of the area product to activate expression of most genes under area control. such mutations can even have a gain-of-function, derepressed phenotype, consistent with a critical role for this region in modulating the activity of the area protein. however, expression of a few gen ...19938437521
operator derepressed mutations in the proline utilisation gene cluster of aspergillus nidulans.the proline utilisation gene cluster of aspergillus nidulans can be repressed efficiently only when both repressing nitrogen and repressing carbon sources are present. we show that two cis-acting mutations in this cluster permit the efficient transcription of the prnb gene under repressing conditions, resulting in direct or indirect derepression of two other transcripts of the pathway. these mutations are transitions that define a 5'gagacccc3' sequence. similar sequences are found upstream of ot ...19938437566
cloning of two isozymes of trichoderma koningii glyceraldehyde-3-phosphate dehydrogenase with different sensitivity to koningic acid.koningic acid inhibits glyceraldehyde-3-phosphate dehydrogenase (gapdh) by binding to the sh group in the active center. the fungus trichoderma koningii, the producer of koningic acid, contains two gapdh isozymes (gapdhs i and ii). gapdh i is inhibited 50% by 1.1.10(-3) m koningic acid, while gapdh ii is inhibited 50% at 6.8 x 10(-6) m. cdnas of the two isozymes were cloned from t. koningii and their nucleotide sequences were determined. the sequence of coding region and codon usage in both clon ...19938439569
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