Publications

aspergillus asexual reproduction and sexual reproduction are differentially affected by transcriptional and translational mechanisms regulating stunted gene expression.	the stunted protein (stuap) is a member of a family of transcription factors that regulate fungal development and cell cycle progression. regulated stua gene expression is required for correct cell pattern formation during asexual reproduction (conidiation) and for initiation of the sexual reproductive cycle in aspergillus nidulans. transcriptional initiation from two different promoters yields overlapping mrnas (stua alpha and stuabeta) that upon translation yield the same protein. here we show ...	1997	9315680
unusual lack of internal mobility and fast overall tumbling in oxidized flavodoxin from anacystis nidulans.	anacystis nidulans flavodoxin, an electron-transfer protein containing a flavin mononucleotide (fmn) molecule as its prosthetic group, has a redox potential for the oxidized/semiquinone equilibrium close to that of free flavin. whereas the redox potential for the semiquinone/hydroquinone equilibrium is more negative. to gain an understanding of the contribution of mobility to redox potential modulation, we studied the backbone mobility of the oxidized a. nidulans flavodoxin at ph 6.6, 303 k by 1 ...	1997	9325102
a model for the combined effects of temperature and salt concentration on growth rate of food spoilage molds.	we modeled mold growth on a solid culture medium at various temperatures and nacl concentrations by using five common food spoilage molds (penicillium roqueforti, trichoderma harzianum, paecilomyces variotii, aspergillus niger, and emericella nidulans). for the description of the growth rate (expressed as the increase in colony diameter per unit of time) as a function of temperature and nacl concentration, a six-parameter model has been developed. the model combines either the rosso-type or the ...	1997	9327540
studies on cellulases of aspergillus nidulans mutants.	mutants were characterized as to their morphology, auxotrophy and cellulase production. no apparent correlation was evident among these characters. the degree of repression or enhancement of the three components of the cellulase enzyme in the mutants varied considerably, indicating their separate genetic control. considerable variations in the enzyme profiles of the mutants were observed as compared to the wild type. enzyme production was also found to be related to development.	1997	9330668
dominant mutations affecting both sporulation and sterigmatocystin biosynthesis in aspergillus nidulans.	the initiation of conidiophore development in the filamentous fungus aspergillus nidulans is a complex process requiring the activities of several genes including flug, flba, flbb, flbc, flbd, and flbe. recessive mutations in any one of these genes result in greatly reduced expression of the brla developmental regulatory gene and a colony morphology described as fluffy. these fluffy mutants have somewhat diverse phenotypes but generally grow as undifferentiated masses of vegetative hyphae to for ...	1997	9339347
inducible expression of yeast mitochondrial citrate synthase in aspergillus nidulans.	the coding region of the mitochondrial citrate synthase gene (cit1) from saccharomyces cerevisiae was amplified by pcr and cloned into an expression vector (pal4) downstream of the alcohol dehydrogenase (alca) promoter of aspergillus nidulans to yield palcs1. transformation of a. nidulans a773 with this construct gave stable transformants, ayc#1 and ayc#2, that were phenotypically stable for several mitotic divisions. southern blot analysis showed that the cit1 gene was successfully integrated i ...	1997	9339892
trichoderma reesei sequences that bind to the nuclear matrix enhance transformation frequency.	three dna fragments, trs1, 2 and 3, were isolated from the trichoderma reesei genome on the basis of their ability to promote autonomous replication of plasmids in saccharomyces cerevisiae. each trs element bound specifically to the isolated t. reesei nuclear matrix in vitro, and two of them bound in vivo, indicating that they are matrix attachment regions (mars). a similar sequence previously isolated from aspergillus nidulans (ans1) was also shown to bind specifically to the t. reesei nuclear ...	1997	9341675
molecular genetics of sulfur assimilation in filamentous fungi and yeast.	the filamentous fungi aspergillus nidulans and neurospora crassa and the yeast saccharomyces cerevisiae each possess a global regulatory circuit that controls the expression of permeases and enzymes that function both in the acquisition of sulfur from the environment and in its assimilation. control of the structural genes that specify an array of enzymes that catalyze reactions of sulfur metabolism occurs at the transcriptional level and involves both positive-acting and negative-acting regulat ...	1997	9343344
the duplication cycle in aspergillus nidulans.	the duplication cycle encompasses the spectrum of events required for the growth and division of individual cells within a fungal hyphae. recent advances in understanding the mechanisms which underlie nuclear division and cellular morphogenesis in the filamentous fungus aspergillus nidulans have shown that in many respects, the duplication cycle differs significantly from the cell cycles of both budding and fission yeast. the purpose of this review is to summarize these advances and to highlight ...	1997	9344627
null alleles of crea, the regulator of carbon catabolite repression in aspergillus nidulans.	crea is the major regulatory protein involved in carbon catabolite repression in aspergillus nidulans. previously we have reported the molecular characterization of a number of in vivo selected mutant alleles and showed that they were unlikely to represent total loss of function alleles (shroff et al., 1996) and that a deletion of the crea gene and surrounding dna has an extremely severe effect on morphology under both carbon catabolite repressing and carbon catabolite nonrepressing conditions ( ...	1997	9344629
chromosome rearrangements in neurospora and other filamentous fungi.	knowledge of fungal chromosome rearrangements comes primarily from n. crassa, but important information has also been obtained from a. nidulans and s. macrospora. rearrangements have been identified in other sordaria species and in cochliobolus, coprinus, magnaporthe, podospora, and ustilago. in neurospora, heterozygosity for most chromosome rearrangements is signaled by the appearance of unpigmented deficiency ascospores, with frequencies and ascus types that are characteristic of the type of r ...	1997	9348657
cloning of the phytases from emericella nidulans and the thermophilic fungus talaromyces thermophilus.	phytases (ec 3.1.3.8) belong to the family of histidine acid phosphatases. we have cloned the phytases of the fungi emericella nidulans and talaromyces thermophilus. the putative enzyme encoded by the e. nidulans sequence consists of 463 amino acids and has a mr of 51785. the protein deduced from the t. thermophilus sequence consists of 466 amino acids corresponding to a mr of 51450. both predicted amino acid sequences exhibited high identity (48% to 67%) to known phytases. this high level of id ...	1997	9349716
deletion of the n-terminal region of the area protein is correlated with a derepressed phenotype with respect to nitrogen metabolite repression.	the entire area gene and a truncated version lacking the sequence encoding the n-terminal 389 amino acids were expressed from the qute promoter and terminator in an aspergillus nidulans strain with the endogenous area gene deleted. this expression system was used to decouple the effects of transcription regulation and mrna stability mediated by the native promoter and terminator from any posttranslational modulation of area activity. both the full-length area protein and the truncated form were ...	1997	9352912
the aspergillus nidulans cnxabc locus is a single gene encoding two catalytic domains required for synthesis of precursor z, an intermediate in molybdenum cofactor biosynthesis.	the aspergillus nidulans complex locus, cnxabc, has been shown to be required for the synthesis of precursor z, an intermediate in the molybdopterin cofactor pathway. the locus was isolated by chromosome walking a physical distance of 65-kilobase pairs from the brla gene and defines a single transcript that encodes, most likely, a difunctional protein with two catalytic domains, cnxa and cnxc. mutations (cnxa) affecting the cnxa domain, mutants (cnxc) in the cnxc domain, and frameshift (cnxb) mu ...	1997	9353296
crystal structure of dna photolyase from anacystis nidulans.	the crystal structure at 1.8 a resolution of 8-hdf type photolyase from a. nidulans shows a backbone structure similar to that of mthf type e. coli photolyase but reveals a completely different binding site for the light-harvesting cofactor.	1997	9360600
molecular characterization of mutants of the acetate regulatory gene facb of aspergillus nidulans.	the facb gene of aspergillus nidulans encodes a dna binding transcriptional activator required for growth on acetate as a sole carbon source. facb contains n-terminal gal4-like zn(ii)2cys6 (or c6 zinc) binuclear cluster dna binding and leucine zipper-like heptad repeat motifs and central and c-terminal acidic alpha-helical regions. facb recessive loss of function mutants are deficient in acetate induction of acetyl-coa synthase, isocitrate lyase, malate synthase, acetamidase, and nadp-isocitrate ...	1997	9367656
6-n-hydroxylaminopurine (hap)-induced accumulation of variability in haploid and diploid strains of aspergillus nidulans.	haploid and diploid strains of aspergillus nidulans have been repeatedly treated with the strong mutagen 6-n-hydroxylaminopurine (hap) which causes only base substitutions. an enormous amount of variability may be rapidly accumulated in haploid or diploid strains of a. nidulans. in particular, in the diploids the analysis of the results shows that after 12 cycles of treatment the conidia differ from each other for about ten recessive lethals and therefore probably for several hundreds of mutatio ...	1997	9371884
characterization of the mitochondrial cytochrome b gene from venturia inaequalis.	a new class of agricultural fungicides derived from the group of antifungal strobilurins acts as specific respiration inhibitors by binding to mitochondrial cytochrome b. the cytochrome b gene was cloned and sequenced from the mitochondrial genome of venturia inaequalis, the causal agent of apple scab. the gene was 10.65 kbp in size and contained seven exons and six introns. the exons encoded a protein of 393 amino acids. comparison of the deduced amino-acid sequence with cytochrome b proteins f ...	1997	9371888
a zinc finger protein required for stationary phase viability in fission yeast.	yeast cells exit the cell cycle and enter a metabolically inert stationary phase when starved for nutrients essential for normal proliferation. we have cloned a novel gene named rsv1+ (required for stationary phase viability) that is essential for fission yeast cell viability in a stationary phase induced by glucose starvation. rsv1+ encodes a 47 kda protein with two zinc finger motifs that are partially homologous with aspergillus nidulans crea, saccharomyces cerevisiae mig1 and mammalian egr-1 ...	1997	9372444
characterization of dnudc, the drosophila homolog of an aspergillus gene that functions in nuclear motility.	nuclear migration plays a prominent role in a broad range of developmental processes. we have cloned a drosophila gene, dnudc, encoding a protein that is evolutionarily conserved between humans and fungi. the aspergillus homolog, nudc, is one of a group of genes required for nuclear migration. dnudc encodes a 38.5-kda protein, and the carboxy terminal half of the protein shares 52% amino acid identity with aspergillus nudc. we show that the structural homology between dnudc and nudc extends to t ...	1997	9376324
nuclear traffic in fungal hyphae: in vivo study of nuclear migration and positioning in aspergillus nidulans.	nuclear migration and nuclear positioning are fundamental processes in all eukaryotic cells. they are easily monitored during hyphal growth of filamentous fungi. we expressed the green fluorescent protein (gfp) as a fusion protein with the putative nuclear localization domain of the transcriptional activator stua in nuclei of aspergillus nidulans and visualized these organelles in living cells. nuclear staining was observed in interphase nuclei but not during mitosis. nuclear division, nuclear m ...	1997	9379904
a rapid method for chromatin structure analysis in the filamentous fungus aspergillus nidulans.	a rapid method for nuclease digestion of aspergillus nidulans chromatin is described. it overcomes the need for nuclear purification or protoplast preparation. the method is valid for the analysis of the nucleosomal repeat length in bulk chromatin, and allows the analysis of nucleosome phasing at a specific locus.	1997	9380523
characterization of oleate-nonutilizing mutants of aspergillus nidulans isolated by the 3-amino-1,2,4-triazole positive selection method.	conidia of aspergillus nidulans were mutagenized with ultraviolet light and were incubated on a special selective medium containing the catalase inhibitor 3-amino-1,2,4-triazole. from approximately 5 x 10(7) viable uv-irradiated conidia tested, 423 stable mutants resistant to 3-amino-1,2,4-triazole were recovered, of which 40 were unable to grow on minimal medium with oleic acid as the sole carbon source. these oleate-nonutilizing (ole-) mutants did not grow on medium with carbon sources requiri ...	1997	9385142
self-splicing activity of the mitochondrial group-i introns from aspergillus nidulans and related introns from other species.	the mitochondrial genome of aspergillus nidulans contains several group-i introns. each one has been assayed for its ability to self-splice in vitro in the absence of proteins. the intron from the apocytochrome b gene is unusual among subgroup ib4 introns in being able to self-splice, unlike a similar intron from saccharomyces cerevisiae. the first intron in the cytochrome oxidase subunit-1 gene self-splices but only correctly completes the first step of splicing; cryptic 3' splice-sites are rec ...	1997	9388295
cloning and characterisation of the adenosyl phosphosulphate kinase gene from aspergillus nidulans.	the sd gene of aspergillus nidulans has been cloned by heterologous screening of rationally selected cosmids. co-transformation of the sd50 mutant jmp1 confirmed the presence of a functional gene. sequence analysis determined this gene to be 680 bp in length, containing a 59-bp intron and encoding a protein of 206 amino acids. a protein-sequence comparison revealed a similarity to the c-terminal region of atp sulphurylase, the sc gene product. further sequence comparison revealed differences in ...	1997	9388296
expression of wild-type and mutated drosophila melanogaster xanthine dehydrogenases in aspergillus nidulans.		1997	9388736
g protein alpha subunit genes control growth, development, and pathogenicity of magnaporthe grisea.	three g protein alpha subunit genes have been cloned and characterized from magnaporthe grisea: maga is very similar to cpg-2 of cryphonectria parasitica; magb is virtually identical to cpg-1 of cryphonectria parasitica, to gna1 of neurospora crassa, and to fada of emericella nidulans; and magc is most similar to gna2 of neurospora crassa. homologous recombination resulting in targeted deletion of maga had no effect on vegetative growth, conidiation, or appressorium formation. deletion of magc r ...	1997	9390422
structure and physiological function of calpains.	for a long time now, two ubiquitously expressed mammalian calpain isoenzymes have been used to explore the structure and function of calpain. although these two calpains, mu- and m-calpains, still attract intensive interest because of their unique characteristics, various distinct homologues to the protease domain of mu- and m-calpains have been identified in a variety of organisms. some of these 'novel' calpain homologues are involved in important biological functions. for example, p94 (also ca ...	1997	9396712
in vitro reconstruction of the aspergillus (= emericella) nidulans genome.	a physical map of the 31-megabase aspergillus nidulans genome is reported, in which 94% of 5,134 cosmids are assigned to 49 contiguous segments. the physical map is the result of a two-way ordering process, in which clones and probes were ordered simultaneously on a binary dna/dna hybridization matrix. compression by elimination of redundant clones resulted in a minimal map, which is a chromosome walk. repetitive dna is nonrandomly dispersed in the a. nidulans genome, reminiscent of heterochroma ...	1997	9405653
relationship of actin, microtubules, and crosswall synthesis during septation in aspergillus nidulans.	studies of cytokinesis in animal cells demonstrate that microtubules play an important role in signaling the position of the actin-containing contractile ring and subsequent formation of the cleavage furrow. septation in several fungi closely resembles animal cell cytokinesis in that a circumferential ring of actin is visible at the incipient division site. however, this does not necessarily mean that division is contractile since actin may also serve to localize septal wall synthesis. in additi ...	1997	9415379
genetic and molecular characterization of murine gata-1 in aspergillus defines a critical role for the n-terminal finger.	we have utilized aspergillus nidulans as a model system for the characterization of the major vertebrate transcription factor gata-1. this has been achieved both by analysing the function of murine gata-1 directly and by using direct gene replacement to introduce chimaeric area::gata-1 derivatives at the area locus, which encodes a gata factor involved in regulating nitrogen metabolism in a. nidulans. although gata-1 shows only limited function when expressed in a. nidulans, the c-terminal gata ...	1997	9680327
microbial models of soil metabolism: biotransformations of danofloxacin.	danofloxacin is a new synthetic fluoroquinolone antibacterial agent under development for exclusive use in veterinary medicine. such use could lead to deposition of low levels of danofloxacin residues in the environment in manure from treated livestock. this study was conducted to evaluate the potential for indigenous soil microorganisms to metabolize danofloxacin. cultures of 72 soil microorganisms representing a diverse panel of bacteria, fungi and yeast were incubated with danofloxacin mesyla ...	1997	9451835
umchs5, a gene coding for a class iv chitin synthase in ustilago maydis.	a fragment corresponding to a conserved region of a fifth gene coding for chitin synthase in the plant pathogenic fungus ustilago maydis was amplified by means of the polymerase chain reaction (pcr). the amplified fragment was utilized as a probe for the identification of the whole gene in a genomic library of the fungus. the predicted gene product of umchs5 has highest similarity with class iv chitin synthases encoded by the chs3 genes from saccharomyces cerevisiae and candida albicans, chs-4 f ...	1997	9454647
the ynt1 gene encoding the nitrate transporter in the yeast hansenula polymorpha is clustered with genes yni1 and ynr1 encoding nitrite reductase and nitrate reductase, and its disruption causes inability to grow in nitrate.	dna sequencing in the phage lambda ja13 isolated from a lambda embl3 hansenula polymorpha genomic dna library containing the nitrate reductase-(ynr1) and nitrite reductase-(yni1) encoding genes revealed an open reading frame (ynt1) of 1524 nucleotides encoding a putative protein of 508 amino acids with great similarity to the nitrate transporters from aspergillus nidulans and chlamydomonas reinhardtii. disruption of the chromosomal ynt1 copy resulted in incapacity to grow in nitrate and a signif ...	1997	9020872
dehydroquinate synthase binds divalent and trivalent cations: role of metal binding in catalysis.		1997	9450037
malic enzyme: a lipogenic enzyme in fungi.		1997	9450097
atp: citrate lyase from aspergillus nidulans.		1997	9450098
emericella nidulans as an agent of guttural pouch mycosis in a horse.	a case is reported in a 9-year-old anglo-arab horse with guttural pouch mycosis caused by emericella nidulans. acute death occurred by exsanguination following erosion of the external carotid artery. histopathological examination of the mycotic plaque demonstrated septate hyphae, conidial heads, hülle cells and mature cleistothecia containing characteristic ascospores. specific identification was confirmed by culture. in accordance with previous reports, emericella nidulans should be considered ...	1997	9467112
detection of aspergillus ribosomal rna using biotinylated oligonucleotide probes.	aspergillosis continues to be a devastating disease entity that results in significant mortality in immunosuppressed patients. rapid diagnosis is often required to initiate appropriate therapy. although the histopathologist may be able to visualize fungal organisms in tissue specimens, the histology of aspergillus species may overlap with a variety of fungi, so diagnosis often relies on fungal cultures that can take weeks to complete. recently, an in situ hybridization assay targeting aspergillu ...	1997	9458383
identification of new regulatory genes controlling synthesis of folate-dependent enzymes in aspergillus nidulans.	prototrophic revertants of a meth2 strain of aspergillus nidulans which is impaired in the regulation of synthesis of folate-dependent enzymes were isolated and six of them analysed. in three of the isolates reversion was the result of an intragenic suppressor mutation in the meth locus. in the remaining strains suppressor mutations occurred in independent genes. these genes, designated fola, folb and folc, are linked and located in chromosome vi. mutations in these genes render synthesis of som ...	1997	9462964
regulation of p34cdc2/cyclinb h1 and nima kinases during the g2/m transition and checkpoint responses in aspergillus nidulans.	in a. nidulans, activation of both p34cdc2/cyclinb h1 and nima kinases is required to initiate mitosis. these two kinases are regulated at several levels during interphase and are activated independently as protein kinases during g2. they are also targeted for negative regulation, to prevent mitosis by mitotic entry checkpoint controls, when dna is not replicated or is damaged. then, to initiate mitosis, they promote each other's mitotic functions to coordinately promote mitosis upon completion ...	1997	9552417
isocitrate lyase from aspergillus nidulans: crystallization and x-ray analysis of a glyoxylate cycle enzyme.	isocitrate lyase (icl) from the filamentous fungus aspergillus nidulans catalyzes the first committed step of the carbon-conserving glyoxylate bypass. this enzyme has been crystallized by the hanging-drop method of vapour diffusion using polyethylene glycol 2000 as the precipitant. diffraction patterns show that the crystals diffract to beyond 2.5 a and are probably in space group p4(2)2(1)2 with unit-cell dimensions of a = b = 91.9 and c = 152.7 a, with one molecule in the asymmetric unit. the ...	1997	15299923
ph regulation of sterigmatocystin and aflatoxin biosynthesis in aspergillus spp.	abstract aflatoxin (af) and sterigmatocystin (st) are toxic secondary metabolites produced by the same biochemical pathway found in several aspergillus spp. the expression of the homologous st/af structural gene, stcu in a. nidulans and ver-1 in a. parasiticus, was affected by external ph of liquid growth media. both stcu and ver-1 mrnas appeared earlier and were expressed at higher levels in cultures grown in acidic media (ph 4 to 6) versus neutral (ph 7) and alkali (ph 8) media. transcript lev ...	1997	18945083
expression of active spinach glycolate oxidase in aspergillus nidulans.	the biocatalytic production of glyoxylic acid from glycolic acid requires two enzymes: glycolate oxidase, which catalyzes the oxidation of glycolic acid by oxygen to produce glyoxylic acid and hydrogen peroxide, and catalase, which decomposes the byproduct hydrogen peroxide. as an alternative to isolation from the leaf peroxisomes of spinach, glycolate oxidase has now been cloned and expressed in transformants of aspergillus nidulans t580 at levels ranging from 1.7 to 36 iu/g dry wt. cells. the ...	1996	18626962
combined expression of aspergillus nidulans endoxylanase x24 and aspergillus oryzae (alpha)-amylase in industrial baker's yeasts and their use in bread making.	the aspergillus nidulans endoxylanase x24 and the aspergillus oryzae (alpha)-amylase cdnas were placed under the control of the saccharomyces cerevisiae actin promoter (pact1) and introduced into baker's yeast. bread made with transformants expressing both enzymes (yepact-amy-act-x24) showed a 30% increase in volume and reduced firmness in comparison with that produced with a commercial strain. endoxylanase x24 and (alpha)-amylase seem to act synergistically to improve the quality of bread in te ...	1996	16535419
photodynamic effects of hypericin on photosynthetic electron transport and fluorescence of anacystis nidulans (synechococcus 6301).	we investigated the photodynamic action of hypericin, a natural naphthodianthrone, on photosynthetic electron transport and fluorescence of the cyanobacterium anacystis nidulans (synechococcus 6301). the most drastic effect was the inactivation of photosynthetic oxygen evolution in the presence of the electron acceptor phenyl-p-benzoquinone in aerobic cells which required 1 hypericin/5 chlorophyll a for half-maximal effect. anaerobic a. nidulans was only partially inactivated and variable chloro ...	1996	24271302
role of ca++/calmodulin binding proteins in aspergillus nidulans cell cycle regulation.	the goal of this review is to summarise the current knowledge concerning the targets of ca++/calmodulin that are essential for cell cycle progression in lower eukaryotes. emphasis is placed on aspergillus nidulans since this is the only organism to date shown to posses essential ca++ dependent calmodulin activated enzymes. two such enzymes are the calmodulin activated protein phosphatase, calcineurin and the calmodulin dependent protein kinase. these proteins, each the product of a unique gene, ...	1996	9552398
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 ...	1996	9022704
cloning of the polyketide synthase gene atx from aspergillus terreus and its identification as the 6-methylsalicylic acid synthase gene by heterologous expression.	southern blot analysis of genomic dnas of several fungi that produce polyketide compounds with the 6-methylsalicylic acid synthase (msas) gene of penicillium patulum as a probe indicated the presence of an msas-homologous gene in the (+)-geodin-producing strain imi 16,043 of aspergillus terreus. the gene, designated atx was cloned from an a. terreus genomic dna library and 7588 bp of the gene together with its flanking regions were sequenced to reveal the presence of a 5.5 kb open reading frame ...	1996	9003280
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 ...	1996	9003303
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 ...	1996	9003309
sorption of cadmium by filamentous soil fungi.	the article presents the evaluation of the short-term sorption of cd by selected soil fungi. the freundlich adsorption isotherm method for metal sorption modelling was applied. fungal strains belonging to two classes, zygomycetes and ascomycetes, were used. altogether, six species from ascomycetes (a. niger, a. nidulans, ps. boydii, t. koningii, p. janthinellum, p. verrucosum) and three from zygomycetes (r. rhizopodiformis, r. oryzae, r. pusillus) were examined. these fungi were selected for exp ...	1996	8997697
nitrogen metabolite signalling involves the c-terminus and the gata domain of the aspergillus transcription factor area and the 3' untranslated region of its mrna.	area is a gata transcription factor which mediates nitrogen metabolite repression in aspergillus nidulans in response to intracellular glutamine levels. we have identified and localized three elements important to modulation of area function: a region of 13 residues within the dna-binding gata domain which forms a putative extended loop structure, the 12 c-terminal residues, and sequences within a 218 nucleotide region of the 3' utr. the 12 c-terminal residues are also required for transcription ...	1996	8654376
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 ...	1996	8670107
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 ...	1996	8670863
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 ...	1996	8674973
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- ...	1996	8674991
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 ...	1996	8682797
a dictyostelium myosin i plays a crucial role in regulating the frequency of pseudopods formed on the substratum.	analysis of the motile behavior of a strain of dictyostelium lacking a myosin i, myoa, revealed that this mutant strain formed pseudopods and turned twice as frequently as wild type cells [titus et al., 1993: mol. biol. cell 4:233-246]. the basis for this aberrant behavior has been explored using three-dimensional reconstructions of translocating cells. wild type cells form approximately 40% of pseudopods on the substratum and 60% off the substratum. the majority of pseudopods formed on the subs ...	1996	8824735
the plasmid replicator ama1 in aspergillus nidulans is an inverted duplication of a low-copy-number dispersed genomic repeat.	the ama1 sequence was isolated from a genomic library of aspergillus nidulans on the basis of its ability to enhance transformation frequency and generate phenotypically unstable transformants in this fungus. these properties were previously shown to be the result of extrachromosomal replication of ama1-bearing plasmids. here we demonstrate that ama1 is an inverted duplication of a sequence which has other isolated genomic copies. these sequences (mobile aspergillus transformation enhancers, or ...	1996	8830247
translational initiation competence, 'leaky scanning' and translational reinitiation in area mrna of aspergillus nidulans.	(1) aug codons that either permit or prevent 'leaky scanning' of mrna encoding area, the transcriptional activator mediating nitrogen metabolite repression in aspergillus nidulans, have been identified. the consensus context for a strong initiation codon (i.e. one preventing 'leaky scanning') derived from this work is gxx aug c/ucx. however, aug codons which do not conform to this consensus are nevertheless able to initiate translation. (2) translational reinitiation can occur within area mrna, ...	1996	8830259
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 ...	1996	9018692
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 ...	1996	9019140
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 ...	1996	9009659
a study of protein-water exchange through the off-resonance roesy experiment: application to the dna-binding domain of alcr.	in this communication a new nmr experiment for the safe observation and quantification of water-protein exchange phenomena is presented. it combines a water-selective pulse, offering chemical shift-based separation, and the off-resonance roesy dynamic filter, which permits the elimination of the unwanted intramolecular dipolar cross relaxation of protein protons. moreover, pulsed field gradients are used for the suppression of radiation damping and the solvent signal. the straightforward incorpo ...	1996	9008364
mutational analysis of the c-terminal region of area, the transcription factor mediating nitrogen metabolite repression in aspergillus nidulans.	in aspergillus nidulans the positive-acting, wide domain regulatory gene area mediates nitrogen metabolite repression. previous analysis demonstrated that the c-terminal 153 residues of the area product (area) are inessential for at least partial expression of most genes subject to regulation by area. paradoxically, arear2, a -1 frameshift replacing the wild-type 122 c-terminal residues with a mutant peptide of 117 amino acids, leads to general loss of function. to determine the basis for the ar ...	1996	8569680
domain structure and function within the quta protein of aspergillus nidulans: implications for the control of transcription.	quta is a positively acting regulatory protein that regulates the expression of the eight genes comprising the quinic acid utilization gene (qut) gene cluster in aspergillus nidulans. it has been proposed that the quta protein is composed of two domains that are related to the n-terminal two domains-dehydroquinate (dhq) synthase and 5-enolpyruvyl shikimate-3-phosphate (epsp) synthase-of the pentadomain arom protein. the arom protein is an enzyme catalysing five consecutive steps in the shikimate ...	1996	8581174
transformation of the cultivated mushroom, agaricus bisporus, to hygromycin b resistance.	application of biotechnology to the cultivated mushroom, agaricus bisporus, has been hampered thus far by the lack of a transformation system. here, transformation of both a homo- and a heterokaryotic strain of a. bisporus to hygromycin b resistance is described. transforming dna was integrated into the a. bisporus genome and stably maintained throughout vegetative growth. transformants of the heterokaryotic strain formed transgenic fruiting bodies. promoters derived from the unrelated ascomycet ...	1996	8602139
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 ...	1996	8602149
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 ...	1996	8602152
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.	1996	8602159
a human peptidyl-prolyl isomerase essential for regulation of mitosis.	the nima kinase is essential for progression through mitosis in aspergillus nidulans, and there is evidence for a similar pathway in other eukaryotic cells. here we describe the human protein pin1, a peptidyl-prolyl cis/trans isomerase (ppiase) that interacts with nima. ppiases are important in protein folding, assembly and/or transport, but none has so far been shown to be required for cell viability. pin1 is nuclear ppiase containing a ww protein interaction domain, and is structurally and fun ...	1996	8606777
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 ...	1996	8611179
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 ...	1996	8617205
the 3-phosphoglycerate kinase gene of the yeast yarrowia lipolytica de-represses on gluconeogenic substrates.	we have isolated the 3-phosphoglycerate kinase (pgk) gene of the yeast yarrowia lipolytica by probing a genomic library with a pcr fragment amplified with primers deduced from two highly conserved regions of various pgks. it is a unique sequence encoding a polypeptide of 417 residues with extensive homology to other pgks, especially to that of aspergillus nidulans (76% identity). the expression of the y. lipolytica pgk1 gene proved to be higher on gluconeogenic substrates than on glycolytic ones ...	1996	8625424
evidence for slta1 as a salt-sensitive allele of the arginase gene (agaa) in the ascomycete aspergillus nidulans.	strains of aspergillus nidulans carrying the slta1 mutation, conferring sensitivity to kcl and nacl, also showed an arginine-sensitive phenotype whereby concentrations of the l-amino acid at or above 10 mm were toxic to growth. sexual progeny of a cross between a slta1 mutant and a wild-type strain showed a co-segregation of salt and arginine sensitivity. similarly, revertants to salt tolerance showed a loss of arginine sensitivity as did slta1 strains that were transformed with a cosmid carryin ...	1996	8625426
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 ...	1996	8625427
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 ...	1996	8625428
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 ...	1996	8625429
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 ...	1996	8625430
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 ...	1996	8628232
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 ...	1996	8631344
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 ...	1996	8631345
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 ...	1996	8643646
cata, a new aspergillus nidulans gene encoding a developmentally regulated catalase.	aspergillus nidulans asexual sporulation (conidiation) is a model system for studying gene regulation and development. the can5 cdna is one of several clones isolated based on transcript induction during conidiation. here we present the molecular characterization of its corresponding gene, demonstrating that it encodes a developmentally regulated catalase, designated cata. the cata 744-amino-acid-residue polypeptide shows significant identity to other catalases. its similarity to prokaryotic cat ...	1996	8598056
characterization of the ugata gene of ustilago maydis, isolated by homology to the gata gene of aspergillus nidulans.	a gene encoding a putative gaba aminotransferase (ugata) was isolated from the basidiomycete ustilago maydis via heterologous hybridization to the gaba aminotransferase gene (gata) of aspergillus nidulans . the derived amino-acid sequence of ugata shows strong identity throughout the protein to the gaba aminotransferase enzymes from a. nidulans and saccharomyces cerevisiae. northern analysis in u. maydis indicated that the ugata transcript is inducible by the omega-amino acids gaba and beta-alan ...	1996	8598057
regulation of beta-glucosidase biosynthesis in aspergillus nidulans.	beta-glucosidase in aspergillus nidulans was found to be both intracellular and extracellular. the intracellular beta-glucosidase was synthesized after the exhaustion of carbon source in the medium. the extracellular enzyme appeared with autolysis of the mycelium. biosynthesis of beta-glucosidase was not induced by various carbohydrates but repressed to varying extents in the presence of glucose, glycerol, and 2-deoxyglucose. this repression was not relieved by addition of camp. the repression w ...	1996	8598280
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 ...	1996	8595677
regulation of folate-dependent enzyme levels in aspergillus nidulans: studies with regulatory mutants.	the synthesis of folate-dependent enzymes in aspergillus nidulans appears to be regulated by intracellular pools of homocysteine and methionine. the results are consistent with the view that homocysteine acts as an inducer and methionine as a corepressor, but the molecular mechanism of the regulation is still unknown. methionine-requiring mutants, meth2 and metd10, apparently allelic, show deregulation of folate-dependent enzymes. most characteristic of the mutants is a repressed level of folylp ...	1996	8645712
the tama gene of aspergillus nidulans contains a putative zinc cluster motif which is not required for gene function.	expression of many nitrogen catabolic enzymes is controlled by nitrogen metabolite repression in aspergillus nidulans. although the phenotypes of tama mutants have implicated this gene in nitrogen regulation, its function is unknown. we have cloned the tama gene by complementation of a new tama allele. the tama sequence shares significant homology with the uga35/dal81/durl gene of saccharomyces cerevisiae. in vitro mutagenesis of sequences encoding a putative zinc cluster dna binding domain indi ...	1996	8655534
[test for the effects of mutagenic toxic fungal metabolites originating from municipal landfill sites].	the purpose of the study is to assess the mutagenic effect of mycotoxins produced by moulds growing on municipal landfill sites. mutagenicity of toxic fungal metabolites was determined by the salmonella plate incorporation assay with two strains of bacteria: ta98 and ta100, with and without metabolic activation. the results obtained indicate that there is a severe hazard caused by these mycotoxins detected main by ta98 with metabolic activation. the most mutagenic mixture of mycotoxins acting di ...	1996	8656997
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 ...	1996	8660469
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 ...	1996	8662005
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 ...	1996	8662194
transformation of the plant pathogenic fungus, rhynchosporium secalis.	the barley leaf scald fungus, rhynchosporium secalis, was transformed to hygromycin-b and phleomycin resistance using the hph gene from e. coli and the ble gene from streptoalloteichus hindustanus under the control of aspergillus nidulans promoter and terminator sequences. plasmid dna was introduced into fungal protoplasts by peg/cacl2 treatment. transformation frequencies varied from 59 to 493 transformants per 10 microg of dna and 5 x 10(7) protoplasts. the antibiotic-resistant phenotype appea ...	1996	8662199
characterization of the aspergillus parasiticus niad and niia gene cluster.	the nitrate reductase gene (niad) and nitrite reductase gene (niia) of aspergillus parasiticus are clustered and are divergently transcribed from a 1.6-kb intergenic region (niad-niia). the deduced aminoacid sequence of the a. parasiticus nitrate reductase demonstrated a high degree of homology to those of other aspergillus species, as well as to leptosphaeria maculans, fusarium oxysporum, gibberella fujikuroi and neurospora crassa, particularly in the cofactor-binding domains for molybdenum, he ...	1996	8662212
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 ...	1996	8662910
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 ...	1996	8690087
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 ...	1996	8692188
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 ...	1996	8694791