PMID(sorted ascending)
genotoxic effects of niclosamide in aspergillus nidulans.a 2-5-month treatment with niclosamide, a widely used drug in developing countries, has been reported to induce lymphosarcomas in toad liver and kidney. the genotoxic effects of this drug have also been evaluated in salmonella typhimurium, in somatic and germinal cells of mice and in human lymphocytes exposed in vitro and in vivo. the present study shows that niclosamide is also capable of inducing mitotic crossing-over and non-disjunction in aspergillus nidulans, which points to the wide potent ...19892649793
identification of gamma-tubulin, a new member of the tubulin superfamily encoded by mipa gene of aspergillus nidulans.microtubules, which are essential for mitosis and many other cytoskeletal functions, are composed primarily of alpha- and beta-tubulin. the properties of microtubules are due, in part, to proteins other than tubulins that are part of, or interact with, microtubules and the identification and characterization of such proteins is important to understanding how microtubules function. analyses of mutations at the mipa (microtubule interacting protein) locus of aspergillus nidulans have suggested tha ...19892649796
transformation in fungi.transformation with exogenous deoxyribonucleic acid (dna) now appears to be possible with all fungal species, or at least all that can be grown in culture. this field of research is at present dominated by saccharomyces cerevisiae and two filamentous members of the class ascomycetes, aspergillus nidulans and neurospora crassa, with substantial contributions also from fission yeast (schizosaccharomyces pombe) and another filamentous member of the class ascomycetes, podospora anserina. however, tr ...19892651864
a translocation associated, loss-of-function mutation in the nitrogen metabolite repression regulatory gene of aspergillus nidulans can revert intracistronically.the arear-18 mutation is a loss-of-function mutation in area, the positive acting regulatory gene mediating nitrogen metabolite repression in aspergillus nidulans. it results from a reciprocal translocation which splits the coding region into 5' and 3' moieties. surprisingly, we have selected rare intracistronic revertants of arear-18. from crosses heterozygous for arear-18 revertant alleles, duplication-deficiency progeny containing two copies of a substantial portion of chromosome iv but lacki ...19892651886
regulatory genes in aspergillus nidulans.a major area for the study of gene regulation in lower eukaryotes has been the coordinated control of catabolic enzyme synthesis. studies of catabolic gene regulation aim to define how interactions between input signals and regulatory proteins are transmitted to the transcription machinery to bring about changes in gene expression. in the past, mutants altered in the utilization of a wide variety of substrates have been characterized in aspergillus nidulans. recently, the development of a transf ...19892652389
interrelated regulation of sulphur-containing amino-acid biosynthetic enzymes and folate-metabolizing enzymes in aspergillus aspergillus nidulans homocysteine can be metabolized both to cysteine and methionine. mutants impaired in the main pathway of cysteine synthesis or in the sulphate assimilation pathway show a low pool of glutathione and elevated levels of homocysteine synthase and of the homocysteine-to-cysteine pathway enzymes. on the other hand, the level of methionine synthase and other enzymes of folate metabolism is depressed in these mutants. this anticoordinated regulation provides a mechanism controll ...19892653822
beta-lactam biosynthetic genes. 19892654524
different action of mms and ems in uv-sensitive strains of aspergillus nidulans.the repair of methyl methanesulfonate (mms) and ethyl methanesulfonate (ems) damages has been investigated in the fungus aspergillus nidulans. 4 uv-sensitive mutants, namely uvsb, uvsd, uvsf and uvsh have been tested for their sensitivity and mutability to the above-mentioned agents. the results obtained show that: (1) uvsb and uvsd mutants are no more sensitive than the wild-type strain to the lethal action of ems. in contrast, they are more sensitive to mms; (2) uvsf and uvsh mutants are more ...19892654626
interactions of three sequentially expressed genes control temporal and spatial specificity in aspergillus development.aspergillus nidulans brla, abaa, and weta form a dependent pathway that regulates asexual reproductive development. the order in which these genes are expressed determines the outcome of development. expression of brla in vegetative cells leads to activation of abaa and weta, cessation of vegetative growth, cellular vacuolization, and spore formation. by contrast, expression of abaa in vegetative cells does not result in conidial differentiation but does lead to activation of brla and weta, cess ...19892655931
the mitochondrial ribosomal rna molecules of aspergillus nidulans.the 16s and 23s mitochondrial rrnas of aspergillus nidulans have been identified by northern hybridisation and the ends of the molecules mapped onto the mitochondrial genome by s1 nuclease analysis. the results show that both the rrna molecules are longer than originally reported, forcing a reassessment of the potential secondary structures that can form in the terminal regions. in particular, structures resembling the 5.8s- and 4.5s-like domains of the bacterial large rrna can now be recognised ...19892656406
molecular characterization of the aspergillus nidulans ya locus.we investigated the molecular organization of the region of aspergillus nidulans chromosome i containing ya, a gene encoding the developmentally regulated enzyme conidial laccase. dna fragments were identified that complemented the ya2 mutation and were shown to correspond to ya by genetic mapping and gene disruption experiments. the molecular map of the region was oriented to the genetic map by testing dna fragments for their ability to complement a mutation in the tightly linked ade gene. the ...19892659435
isolation of a sexual sporulation hormone from aspergillus nidulans.psi factor is a substance produced by aspergillus nidulans that induces premature sexual sporulation. chromatographic analysis of psi-active extracts showed that psi activity resides in several different forms. two of the forms, psia1 and psib1, have been isolated and have been shown to have closely similar compositions. the most abundant form, psia1, reacts with alcohols in acidic solution by the addition of one entire molecule of the alcohol. this reaction, which is reversible, suggests that p ...19892661541
sterigmatocystin production on complex and defined substrates. 19892662007
nucleotide sequence of the aspergillus nidulans mitochondrial gene for subunit 5 of nadh dehydrogenase. 19892662141
the genetic analysis of mitosis in aspergillus nidulans.we describe here recent work on the molecular genetics of mitosis in the filamentous fungus aspergillus nidulans. aspergillus is one of three simple eukaryotes with powerful genetic systems that have been used to analyze mitosis. the modern molecular biological techniques available with this organism have made it possible to use mutations to identify genes and proteins that play an important role in mitosis. three aspergillus genes that affect mitosis are described. one gene, nima, is specifical ...19892662965
chromosomal mapping and gene disruption of the adhiii gene in aspergillus nidulans.there are at least three alcohol dehydrogenases in aspergillus nidulans. adhiii has no obvious physiological function. we describe here the cloning of the adhiii gene (alcc), its mapping on linkage group vii by "reverse genetics", and the properties of multicopy transformants tested for their ability to grow on a range of alcohols (butan-1-ol being the best substrate tested for growth). we were unable to detect any obvious alteration in phenotype of a strain carrying a disrupted copy of the adhi ...19892663191
developmentally related changes in the production and expression of endo-beta-1,4-glucanases in aspergillus nidulans.the production and electrophoretic expression of endoglucanase(s) were compared in the wild-type and three developmental mutants of aspergillus nidulans. in the wild type, the production of endoglucanase and its distribution in extracellular and intracellular fractions varied with the age of the culture and the yield was better in stable cultures (production of conidia and cleistothecia) as compared with shake cultures (vegetative hyphae only). two developmental mutants, aco-t69 and aco-40, whic ...19892663642
the proline transport protein of aspergillus nidulans is very similar to amino acid transporters of saccharomyces aspergillus nidulans, the gene prnb encoding the major proline transport system is one of a cluster of four genes necessary and sufficient for the utilization of proline as sole nitrogen and/or carbon source. the prn cluster has been cloned and the sequence and transcript map of the prnb gene are presented in this paper. the predicted translated sequence consists of 570 amino acids, resulting in a molecular weight of 63,028 daltons. its hydropathy profile shows 10 hydrophobic segments typical ...19892664423
cloning and physical characterization of the l-proline catabolism gene cluster of aspergillus nidulans.the proline catabolism gene cluster of aspergillus nidulans was cloned using a 'brute force' technique which detects clones hybridizing to restriction fragments overlapping chromosomal rearrangements. a number of deletion mutations and a translocation mutation in the cluster have been physically mapped, and an excellent correlation between the genetic and physical maps was established. transcripts have been identified and orientated for each of the four genes of the cluster. all are monocistroni ...19892668692
nucleotide sequence of the only unidentified reading frame in the aspergillus nidulans mitochondrial genome. 19892668894
electrophoretic karyotype of aspergillus electrophoretic karyotype of aspergillus nidulans has been obtained using contour-clamped homogeneous electric field gel electrophoresis. six chromosomal bands were separated, with two of the bands migrating as doublets. using the schizosaccharomyces pombe and saccharomyces cerevisiae chromosomes as size standards, we estimate the sizes of the chromosomes to be between 2.9 and 5.0 megabase pairs (mb) with a total genome size of approximately 31 mb. four of the eight genetic linkage groups wer ...19892668960
isolation and characterization of the 3-phosphoglycerate kinase gene (pgk) from the filamentous fungus trichoderma reesei.the 3-phosphoglycerate kinase gene (pgk) from trichoderma reesei was isolated by hybridization with the corresponding saccharomyces cerevisiae pgk gene. the 1,545 nt long nucleotide sequence of the cloned gene codes for a 416 amino acid protein. the coding sequence contains two introns of 219 and 75 nt, respectively, at positions identical to those corresponding genes from the other filamentous fungi aspergillus nidulans and penicillum chrysogenum. this gene codes for two mrnas of about 1.65 kb ...19892670282
characterization of the amdr-controlled lama and lamb genes of aspergillus nidulans.four aspergillus nidulans genes are known to be under the control of the trans-acting regulatory gene amdr. we describe the isolation and initial characterization of one of these amdr-regulated genes, lama. the lam locus, however, was found to consist of two divergently transcribed genes, the lama gene, and a new gene, also under amdr control, which we have designated lamb. using recombinant dna techniques we have constructed a strain of a. nidulans lacking a functional lamb gene. experiments co ...19892670667
a gene coding for the uric acid-xanthine permease of aspergillus nidulans: inactivational cloning, characterization, and sequence of a cis-acting aspergillus nidulans, integration of transforming sequences can proceed through recombination with homologous sequences or at heterologous sites in the genome. in a strain with a large deletion in the gene coding for acetamidase (amds), a plasmid carrying this gene integrates into and inactivates uapa, the putative structural gene for uric acid-xanthine permease, with a frequency of 0.3%. the integration event occurs 3' to the open reading frame of amds. a 10-nucleotide sequence which occurs ...19892670668
cloning of the nitrate reductase gene (niad) of aspergillus nidulans and its use for transformation of fusarium heterologous transformation system for the phytopathogenic fungus fusarium oxysporum has been developed based on the use of the aspergillus nidulans nitrate reductase gene (niad). f. oxysporum nia- mutants were easily selected by chlorate resistance. the a. nidulans niad gene was isolated from a gene library by complementation of an a. nidulans niad mutant. the cloned gene is capable of transforming f. oxysporum nia- mutants at a frequency of up to ten transformants per microgram of dna. sout ...19892670677
gene function identified by interspecific transformation.aspergillus nidulans is able to utilize 2-pyrrolidinone as a nitrogen source while two related aspergillus species, a. niger and a. terreus, cannot. mutations in the lama gene of a. nidulans prevent growth on 2-pyrrolidinone. a plasmid (plam7) has been isolated containing the a. nidulans lama gene and a divergently transcribed adjacent gene of unknown function. transformation of a. terreus with subclones of plam7 showed that both genes are essential for the utilization of a new nitrogen source, ...19892670678
a single, phosphate-repressible deoxyribonuclease, dnase a, secreted in aspergillus nidulans.high levels of nuclease activities were identified in filtrates of aspergillus cultures after growth in low-but not in high-phosphate media. deoxyribonuclease activities, characterized extensively by column chromatography, showed a coincident single peak for ss- and ds-dnase which was distinct from the peak for rnase. both ss-dnase and ds-dnase are endonucleolytic and showed the highest activity in the presence of ca2+ and mn2+ (at ph 8.0). they also showed identical heat sensitivities suggestin ...19892673210
transformation of seven species of filamentous fungi using the nitrate reductase gene of aspergillus nidulans.a gene transfer system originally developed for fusarium oxysporum has been applied to seven species of filamentous fungi of agricultural and industrial importance. this transformation system relies on the selection of mutants deficient in nitrate reductase by positive screening. such mutants were recovered easily in all the fungi tested--without mutagenic treatments--through their resistance to chlorate. they were transformed by a plasmid vector (pan301) carrying the aspergillus nidulans wild-t ...19892673557
cloning of the crea gene from aspergillus nidulans: a gene involved in carbon catabolite repression.the crea gene from a. nidulans has been cloned by complementation of a non-revertable mutant allele using a genomic library and marker rescue techniques. the rescued sequence was subcloned and a 2.3 kb fragment identified which complements several crea mutant alleles. northern analyses showed that crea encodes a transcript of approximately 1.8 kb in length and that the levels of this transcript varied by up to two fold depending on the carbon source. transformants containing more than two extra ...19892673558
characterization of an inducible expression system in aspergillus nidulans using alca and tubulin-coding genes.plasmids have been constructed in which expression of a gene can be placed under the control of the inducible promoter of the alca gene encoding alcohol dehydrogenase i in aspergillus nidulans. simplified shuttle vectors carrying pyr4 which complements pyrg89 mutations have also been constructed. these are based on puc19 and retain alpha-peptide expression. the beta-tubulin genes, tubc and bena, have been placed under the control of alca and their expression studied. levels of expression can be ...19892673931
disparate evolution of yeasts and filamentous fungi indicated by phylogenetic analysis of glyceraldehyde-3-phosphate dehydrogenase genes.genes encoding glyceraldehyde-3-phosphate dehydrogenase (ec from several evolutionarily disparate organisms were used to construct a phylogenetic tree by evolutionary parsimony. the gapdh tree indicates that, in contrast to the presently accepted taxonomy of fungi, the yeasts saccharomyces cerevisiae and zygosaccharomyces rouxii evolved separately from the filamentous ascomycetes (such as aspergillus nidulans) with which these yeasts are classified. according to this tree, the saccharo ...19892674943
endochitinase from aspergillus nidulans implicated in the autolysis of its cell endochitinase from centrifuged autolyzed cultures of aspergillus nidulans has been purified 100 times. the enzyme has mw 27,000, pi of 4.8 units, ph optimum around 5 ph units. it is unstable at temperature greater than 70 degrees c and does not have a cation requirement. it is inhibited by hg2+, cu2+, ca2+ and ag+ and it does not have muramidase activity. the enzyme depolymerizes chitin rapidly with production of high molecular weight polysaccharides, and then slowly degrades these with produ ...19892676705
the highly divergent beta-tubulins of aspergillus nidulans are functionally internal 1.4-kb bst eii fragment was used to disrupt the bena gene and establish heterokaryons. the heterokaryons demonstrated that the molecular disruption of bena results in a recessive bena null mutation. conidia from a heterokaryon swell and germinate but cannot undergo nuclear division and are thus inviable. a chimeric beta-tubulin gene was constructed with the bena promoter driving the tubc structural gene. this chimeric gene construction was placed on a plasmid containing a selectable ...19892681229
isolation and analysis of the acetate regulatory gene, facb, from aspergillus nidulans.the facb gene of aspergillus nidulans is thought to be involved in acetate induction of enzymes required for acetate utilization and of the acetamidase encoded by the multiply regulated amds gene. in addition, some evidence suggests that the facb gene has a structural as well as a regulatory role in acetate metabolism. the facb gene was cloned from a cosmid library by complementation of the facb101 loss-of-function mutation. transformants receiving multiple copies of facb displayed stronger grow ...19892685573
aspergillus findings in aids patients suffering from cryptococcosis.because of the known pathogenicity of cryptococcus neoformans and of aspergilli depending on defined but different immunodeficiencies of the host, the evaluation of their simultaneous cultural detection in specimens of the respiratory tract of aids patients is of epidemiological, diagnostic, pathogenetic and therapeutic interest. in 10 out of 15 aids patients the following species of the genus aspergillus could be isolated either once or repeatedly during the course of cr. neoformans infections ...19892685598
a gene transfer system based on the homologous pyrg gene and efficient expression of bacterial genes in aspergillus oryzae.a homologous transformation system for aspergillus oryzae is described. the system is based on an a. oryzae strain deficient in orotidine-5'-phosphate decarboxylase (pyrg) and the vector pao4-2, which contains a functional a. oryzae pyrg gene as selection marker. transformation of the a. oryzae pyrg mutant with circular pao4-2 resulted in the appearance of pyr+ transformants at a frequency of up to 20 per micrograms of dna, whereas with linear pao4-2 up to 200 transformants per micrograms dna we ...19892688930
a comparative study on ethanol and acetaldehyde as inducers of chromosome malsegregation in aspergillus nidulans.the activity of ethyl alcohol and acetaldehyde on mitotic chromosome segregation and conidial germination in aspergillus nidulans was studied. ethanol effectively induced malsegregation in a narrow range of concentrations (4.5-5.5%, v/v) and was inactive at doses which arrested conidial germination (above 6%). the same bell-shaped dose-response curve was shown by the spindle poison chloral hydrate, which was active in the range 6-10 mm. acetaldehyde displayed a diphasic dose-response curve. gene ...19892689879
cloning and characterization of the trpc gene from an aflatoxigenic strain of aspergillus parasiticus.the trpc gene in the tryptophan biosynthetic pathway was isolated from an aflatoxigenic aspergillus parasiticus by complementation of an escherichia coli trpc mutant lacking phosphoribosylanthranilate isomerase (prai) activity. the cloned gene complemented an e. coli trpc mutant deficient in indoleglycerolphosphate synthase (igps) activity as well as an aspergillus nidulans mutant strain that was defective in all three enzymatic activities of the trpc gene (glutamine amidotransferase, igps, and ...19892690735
rhizoxin resistant mutants with an altered beta-tubulin gene in aspergillus nidulans.rhizoxin and ansamitocin p-3 (a maytansinoid compound), potent inhibitors of mammalian brain tubulin assembly, inhibit growth of a variety of fungi including aspergillus nidulans. mutants of a. nidulans, bena10 which is a benomyl resistant beta-tubulin gene mutant and tuba1 which is a benomyl supersensitive alpha-tubulin gene mutant, were both sensitive to rhizoxin and ansamitocin p-3 to the same extent as wild-type strains. we isolated 18 rhizoxin resistant mutants of a. nidulans. all of these ...19892691873
rna-mediated genetic transformation in aspergillus nidulans.we developed a model-system for correcting genetic alterations of an aspergillus nidulans strain (ribo, paba, bio, w, acr) by treating protoplasts with total rna extracted from another a. nidulans strain bearing wild type alleles for the same genetic markers. the results revealed the occurrence of a true genetic transformation. the phenomenon was rna-dependent since it was abolished by pancreatic ribonuclease treatment. the term retrotransformation is proposed since the rna messages artificially ...19892692827
beta-n-acetylglucosaminidase from aspergillus nidulans which degrades chitin oligomers during autolysis.a hexosaminidase from autolyzed cultures of aspergillus nidulans was purified 196 fold and characterized as a beta-n-acetylglucosaminidase (ec the enzyme has a mw of 190000, a pi of 4.3, and optimum ph of 5.0 and is unstable at temperatures above 50 degrees c. the enzyme is a glycoprotein with 19.5% sugars, mannose being the principal component. it binds strongly to chitin. the enzyme hydrolyzes different substrates. the ki with the competitive inhibitor 2-acetamido-2-deoxy-d-gluconol ...19892693201
genetic transformation of the filamentous yeast, trichosporon cutaneum, using dominant selection efficient transformation system for the filamentous yeast, trichosporon cutaneum, has been developed. transformation was obtained with plasmids carrying either the escherichia coli hygromycin b phosphotransferase-encoding gene (hph) or the streptoalloteichus hindustanus phleomycin-resistance gene (ble), as dominant selection markers. expression of both resistance-conferring genes was controlled by the gpd promoter and the trpc terminator, from aspergillus nidulans. the transformation frequenc ...19892693213
characterization of purine hydroxylase i from aspergillus nidulans.purine hydroxylase i from aspergillus nidulans was purified 850-fold. the purified preparations exhibited the spectral and catalytic properties, including broad specificity for oxidizing and reducing substrates, typical of molybdenum/flavin/iron-sulphur-containing hydroxylases (oxotransferases).19892693595
immunochemical assay applied to mycotoxin biosynthesis: elisa comparison of sterigmatocystin production by aspergillus versicolor and aspergillus nidulans.conventional thin layer and instrumental methods for analyzing mycotoxins and their precursors are time-consuming and make the investigation of mycotoxin biosynthesis particularly difficult. as an alternative, sensitive enzyme-liked immunosorbent assays (elisas) can be utilized to analyze for these compounds. in this report, sterigmatocystin production in test tube cultures of aspergillus versicolor atcc 18643 and aspergillus nidulans atcc 32610 were compared using competitive elisa. polyclonal ...19892693965
on the mechanisms of induced aneuploidy in aspergillus nidulans and validation of tests for genomic mutations. 19892696976
[relation of bronchial asthma and allergic bronchopulmonary aspergillosis].an allergological examination was conducted in 30 out of 83 (36.07%) patients showing symptoms of bronchial asthma. it was found that skin hypersensitivity to aspergilla allergens coupled with a high serum ige level. the appropriateness of such affection referral to a separate nosological entity (allergic bronchopulmonary aspergillosis) is under discussion.19892697785
aspergillus nidulans as a test organism for the detection of chemically-induced mitotic crossing-over and chromosome malsegregation.the genetic systems developed in the mould aspergillus nidulans to study the chemical induction of mitotic genetic segregation were used to investigate the mechanism of aneuploidy induction by the main benzene hydroxy metabolites. detailed genetic analysis of mitotic segregants produced by individual colonies revealed the simultaneous occurrence of both whole chromosome segregants and mitotic cross-overs, i.e. a pattern not compatible with the induction of numerical abnormalities as the primary ...19892698601
keratinolytic fungi of wadi qena in egypt.forty-six soil samples collected from different sites of wadi qena were examined for keratinophilic fungi using the hair baiting technique. thirty-two species in addition to one variety of each of a. nidulans and a. flavus which belong to eighteen genera were recovered. aspergillus, chrysosporium, penicillium, microsporum and fusarium were the most frequent genera developed from baited soils.19892707686
partial characterization of the gene coding for subunit iv of soybean mitochondrial nadh using the spinach chloroplast atpe gene (epsilon-subunit coding gene) as a probe we have isolated, from a soybean mitochondrial dna library, a sequence containing a 405 base-pairs (bp) open-reading frame (orf). this orf, which is unique in the soybean mitochondrial genome, is probably part of an exon of the gene coding for subunit iv of the nadh dehydrogenase complex. the predicted protein shows 42% sequence similarity with the c-terminal region the aspergillus nidulans nad4 protein. the gene ...19892743433
improved transformation efficiency of aspergillus niger using the homologous niad gene for nitrate reductase.aspergillus niger transformation frequencies of up to 1,176 transformants per micrograms dna were achieved using the plasmid vector psta10 containing the a. niger nitrate reductase structural gene. analysis of genomic endonuclease cleaved dna from nitrate utilising transformants by dna hybridisation, showed that most integration events are as a result of homologous recombination. the niad transformation system was used successfully for the introduction of the unselected escherichia coli fusion g ...19892791035
instability of tn5 inserts in cyanobacterial cloning vectors.transposon tn5 was used to produce random insertions in two hybrid cloning vectors for the unicellular cyanobacterium anacystis nidulans. the transposon-containing plasmids were used to localize essential replication functions and to characterize the stability of large inserts in these vectors. the effect of the insertions on plasmid function was tested by transformation into a derivative of a. nidulans that had been cured of the endogenous plasmid used to construct the vectors. a region of appr ...19872820923
isolation and physical characterization of three essential conidiation genes from aspergillus nidulans.we cloned and characterized three genes from aspergillus nidulans, designated brla, abaa, and weta, whose activities are required to complete different stages of conidiophore development. inactivation of these genes causes major abnormalities in conidiophore morphology and prevents expression of many unrelated, developmentally regulated genes, without affecting the expression of nonregulated genes. the three genes code for poly(a)+ rnas that begin to accumulate at different times during conidiat ...19872823119
transformation of aspergillus based on the hygromycin b resistance marker from escherichia coli.a new, heterologous, dominant marker for selection of aspergillus transformants is described. this marker is based on the escherichia coli hygromycin b (hmb) phosphotransferase gene (hph). expression of the hph gene is controlled by a. nidulans gpd and trpc expression signals. an aspergillus transformation vector was constructed which contains this marker and confers hmb resistance to aspergillus species. with both a. niger and a. nidulans, transformation frequencies of 5-20 transformants per mi ...19872824287
sequence and centromere proximal location of a transformation enhancing fragment ans1 from aspergillus nidulans.the aspergillus nidulans sequence ans1, previously known to enhance transformation frequencies of pyr4-based vectors, was shown to enhance the efficiency of argb and trpc-based vectors. increased efficiencies could be obtained by constructing vectors containing argb and ans1 or by cotransforming selectable plasmids (containing argb, trpc, or pyr4) with the non-selectable ans1 sequence. the preponderance of evidence suggests that the mechanism of ans1 activity does not involve homologous recombin ...19872825130
the pentafunctional arom enzyme of saccharomyces cerevisiae is a mosaic of monofunctional domains.the nucleotide sequence of the saccharomyces cerevisiae aro1 gene which encodes the arom multifunctional enzyme has been determined. the protein sequence deduced for the pentafunctional arom polypeptide is 1588 amino acids in length and has a calculated mr of 174555. functional regions within the polypeptide chain have been identified by comparison with the sequences of the five monofunctional escherichia coli enzymes whose activities correspond with those of the arom multifunctional enzyme. the ...19872825635
isolation and identification of the aspergillus nidulans gdha gene encoding nadp-linked glutamate dehydrogenase.the neurospora crassa am gene was used as a heterologous probe to identify clones from two independently constructed aspergillus nidulans gene libraries. these clones have a common hindiii 1.85 kb fragment. this a. nidulans nucleotide stretch hybridises to a n. crassa 2.7 kb bamhi fragment of wild type dna but not to a co-migrating fragment from the dna of the n. crassa am132 deletion mutant. one a. nidulans clone was shown to complement the n. crasse am132 deletion strain. the n. crassa transfo ...19862834076
regulation of alcr, the positive regulatory gene of the ethanol utilization regulon of aspergillus nidulans.the alcr positive control gene is necessary for the expression of both alca (coding for alcohol dehydrogenase adh i), and alda (coding for aldehyde dehydrogenase, alddh) in aspergillus nidulans. using a cloned alcr probe and northern blots analysis we show that: (1) alcr itself is inducible; (2) alcr inducibility depends on the expression of the alcr gene itself; and (3) alcr is subject to carbon catabolite repression and its expression is controlled by the negatively acting crea wide specificit ...19872834622
multiple copies of the amds gene of aspergillus nidulans cause titration of trans-acting regulatory has been established that a plasmid containing the amds gene of aspergillus nidulans may be used to transform amds+ strains by selecting for increased utilization of acetamide as sole nitrogen source. analysis of transformants has shown that multiple tandem copies of the plasmid can be integrated into the chromosome, commonly at sites other than the amds locus. while the transformed phenotype was relatively stable through mitotic and meiotic divisions evidence was found for variation in plasm ...19872835171
identification and isolation of a putative permease gene in the quinic acid utilization (qut) gene cluster of aspergillus nidulans.mutations in the qutd gene of aspergillus nidulans cause the loss of ability to grow upon quinic acid as sole carbon source in media at normal ph 6.5 and failure to induce three enzyme activities specifically required for metabolism to protochatechuic acid. all 9 qutd mutants recovered are recessive and have been found to be ph sensitive, growing strongly on quinic acid media at ph 3.5 and producing significant induced enzyme activities. these properties are consistent with the hypothesis that t ...19872835177
calmodulin-dependent multifunctional protein kinase in aspergillus nidulans.a ca2+/calmodulin (cam)-dependent multifunctional protein kinase has been isolated from aspergillus nidulans and purified to homogeneity. unlike any cam-dependent multifunctional protein kinase described previously, the native enzyme from aspergillus behaves as a monomer. the calculated molecular weight is 41,200. nadodso4/page reveals a single protein band with an apparent mr of 51,000. two-dimensional isoelectric focusing/nadodso4/page of the purified enzyme showed one major and one minor more ...19882835766
the complex arom locus of aspergillus nidulans. evidence for multiple gene fusions and convergent evolution.the physical positions of the dna sequences encoding the five consecutive enzyme activities required to metabolise 3-deoxy-d-arabino-heptulosonic acid-7-phosphate to 5-enolpyruvyl-shikimate-3phosphate, which are encoded by the a. nidulans arom polypeptide have been determined. subfragments of the arom locus encoding epsp synthase and 3-dehydroquinase have been expressed in appropriate e. coli aro mutants. the dna sequence of the a. nidulans arom locus has been shown to have homology with the cor ...19872836080
transformation of aspergillus niger using the homologous orotidine-5'-phosphate-decarboxylase gene.a homologous transformation system for the filamentous fungus aspergillus niger has been developed, based on the orotidine-5'-phosphate-decarboxylase gene. a. niger pyr- mutants have been selected from 5-fluoro-orotic acid resistant mutants. these mutants were found to comprise two complementation groups, pyra and pyrb. the a. niger omp-decarboxylase gene was isolated from a gene library by heterologous hybridization with the neurospora crassa pyr4 gene. the cloned gene is capable to transform a ...19872836081
nucleotide sequence of the aspergillus niger trpc gene: structural relationship with analogous genes of other organisms.the nucleotide sequence of the aspergillus niger tryptophan c (trpc) gene was determined. northern hybridization and s1-mapping experiments showed the presence of a 2.6 kb trpc poly(a)+ rna with two very short (5 and 6 nucleotides) noncoding 5'-regions. comparison of the predicted amino acid sequence with that of trp gene proteins of pro- and eukaryotic organisms revealed three functional domains (g, c, f) in the a. niger trpc protein which catalyse the glutamine amidotransferase reaction (gat), ...19882836085
an amds-lacz fusion for studying gene regulation in aspergillus.a translational fusion has been constructed between the amds gene of aspergillus nidulans and the lacz gene of escherichia coli. sequencing across the fusion junction confirmed the generation of an in-frame fusion at amino acid 34 of amds and a novel protein has been detected in transformants carrying the fusion plasmid. transformants of a. nidulans and aspergillus niger carrying the fusion plasmid were obtained by co-transformation with a second selectable plasmid. these transformants were read ...19882838387
isolation and transformation of the pyruvate kinase gene of aspergillus nidulans.the aspergillus nidulans pyruvate kinase gene was isolated by heterologous hybridization using the corresponding yeast gene as a probe. a 2.9 kb ecori/bamhi fragment, which exclusively hybridized to the yeast gene, was subcloned in pbr322. this clone was used to transform an a. nidulans pkia deletion mutant to pki+. the analysis of transformants with respect to the kind of integration revealed about 80% homologous integration--55% by a double cross-over event (type iii integration), 25% by a sin ...19882839306
do metal ions promote the re-activation of the 2,3-bisphosphoglycerate-independent phosphoglycerate mutases?it has been reported [smith, mcwilliams & hass (1986) biochem. biophys. res. commun. 136, 336-340] that addition of certain metal ions, notably co2+ and mn2+, promoted the refolding of denatured phosphoglycerate mutase from wheat germ. we have re-investigated these experiments and have shown that, when precautions are taken to avoid artefacts in the assay system, the metal ions do not promote any re-activation of the denatured wheat-germ or aspergillus nidulans enzymes. an alternative explanatio ...19882844142
differences in the regulation of aldehyde dehydrogenase genes in aspergillus niger and aspergillus order to study mechanisms of gene regulation in a. niger, and to compare these to similar systems in a. nidulans, a gene encoding an aldehyde dehydrogenase enzyme has been cloned. in wild-type strains of a. niger the gene shows expression which is regulated by induction and repression. levels of induction by various compounds and the extent of repression under various growth conditions differs from that seen for the a. nidulans alda gene. unlike the a. nidulans alda gene, the a. niger gene ha ...19882846191
the effect of sorbose on nad(p)ase production by aspergillus nidulans.1. nad(p)ase activity was stimulated when 1% sorbose was present in the culture medium of a. nidulans, and this effect was partially reversed by 1% glucose. 2. the level of extracellular nad(p)ase was more affected by sorbose in the culture medium than the intracellular enzyme and no morphological changes were obtained. 3. the sorbose effect on nad(p)ase activity appears to be specific since two other exoenzymes tested (beta-glucosidase and alkaline protease) show normal secretion patterns. 4. t ...19882853639
nitrogen catabolite repression in yeasts and filamentous fungi. 19852869649
the atp synthase subunit 9 gene of aspergillus nidulans: sequence and transcription.we have determined the nucleotide sequence of the aspergillus nidulans nuclear gene olic31, which encodes subunit 9 of mitochondrial atp synthase. the open reading frame contains no introns and specifies a predicted protein of 143 amino acids comprising a pre-sequence of 62 residues and a mature protein of 81 residues. the amino acid homology with the equivalent neurospora crassa protein is 50% for the pre-sequence and 80% for the mature protein. a comparison with this and other imported mitocho ...19862880279
the involvement of glutamine synthetase/glutamate synthase in ammonia assimilation by aspergillus nidulans.wild-type aspergillus nidulans grew equally well on nh4cl, kno3 or glutamine as the only nitrogen source. nadp+-dependent glutamate dehydrogenase (ec and glutamine synthetase (gs; ec activities varied with the type and concentration of nitrogen source supplied. glutamate synthase (gogat) activity (ec was detected but it was almost unaffected by the type and concentration of nitrogen source supplied. ion exchange chromatography showed that the gogat activity was due to ...19872888838
cloning and nucleotide sequence of the aroa gene of bordetella pertussis.the aroa locus of bordetella pertussis, encoding 5-enolpyruvylshikimate 3-phosphate synthase, has been cloned into escherichia coli by using a cosmid vector. the gene is expressed in e. coli and complemented an e. coli aroa mutant. the nucleotide sequence of the b. pertussis aroa gene was determined and contains an open reading frame encoding 442 amino acids, with a calculated molecular weight for 5-enolpyruvylshikimate 3-phosphate synthase of 46,688. the amino acid sequence derived from the nuc ...19882897356
isolation and characterization of the aspergillus niger trpc gene.the aspergillus niger trpc gene was isolated by complementation experiments with an escherichia coli trpc mutant. plasmid dna containing the a. niger trpc gene transforms an aspergillus nidulans mutant strain, defective in all three enzymatic activities of the trpc gene, to trp+, indicating the presence of a complete and functional trpc gene. southern blot analysis of dna from these trp+ transformants showed that plasmid dna was present but that this dna was not integrated at the site of the chr ...19852936650
a cloned tryptophan-synthesis gene from the ascomycete cochliobolus heterostrophus functions in escherichia coli, yeast and aspergillus nidulans.a gene (trp1) in the tryptophan biosynthetic pathway of the fungal plant pathogen cochliobolus heterostrophus was isolated by complementation of an escherichia coli trpf mutant which lacked phosphoribosylanthranilate isomerase (prai) activity. the cloned gene also complemented an e. coli trpc mutant lacking indoleglycerolphosphate synthase (igps) activity, a yeast trp1 mutant missing prai activity and an aspergillus nidulans trpc mutant. it functioned in e. coli and a. nidulans without apparent ...19862941339
genetics of filamentous fungi. 19862945991
amino acid transport in eucaryotic microorganisms. 19862947629
localization of alkaline phosphatase activity at microbody membranes of neurospora crassa and aspergillus nidulans.hyphal cells of neurospora crassa and aspergillus nidulans, grown in sabouraud glucose broth or in a defined medium with xanthine or its catabolites as the nitrogen source, contained single membrane-bound organelles cytochemically identified as microbodies. modified gomori procedures at the ultrastructural level revealed putative alkaline phosphatase activity sites in thin sections of cells of both species of fungi. microbody membranes displayed electron opaque deposits (lead phosphate) which we ...19862948778
sequence analysis and transformation by the catabolic 3-dehydroquinase (qute) gene from aspergillus nidulans.the induction of catabolic 3-dehydroquinase by quinic acid in aspergillus nidulans has been shown to involve transcriptional control and yields a single major 0.8 kb mrna. the nucleotide sequence of the catabolic 3-dehydroquinase qute gene has been determined and contains a single uninterrupted open reading frame of 462 bases encoding a 16,505 da protein of 153 residues. comparison with the corresponding qa2 gene of neurospora crassa reveals the absence of 75 nucleotides encoding 25 amino acids ...19862949740
fungal small nuclear ribonucleoproteins share properties with plant and vertebrate u-snrnps.snrnas with properties closely related to those of the major vertebrate u-snrnas are present in the fungi aspergillus nidulans, neurospora crassa and schizosaccharomyces pombe. these rnas possess a tri-methyl guanosine cap structure and a subset cross-hybridizes with human u1 and u2 clones. in the form of snrnps, snrnas from these fungi as well as from saccharomyces cerevisiae and pea plants are immunoprecipitated by human and anti-sm or anti-(u1)rnp autoimmune antibodies. on micro-injection int ...19872953599
complementation of area- regulatory gene mutations of aspergillus nidulans by the heterologous regulatory gene nit-2 of neurospora crassa.loss-of-function mutations in the regulatory gene area of aspergillus nidulans prevent the utilization of a wide variety of nitrogen sources. the phenotypes of nit-2 mutants of neurospora crassa suggest that this gene may be analogous to the area gene. transformation has been used to introduce a plasmid containing the nit-2 gene into a. nidulans. the nit-2 gene of neurospora complemented mutations in the area gene, restoring the ability to use a variety of nitrogen sources. this indicated that t ...19872954160
high level of complexity of small nuclear rnas in fungi and plants.the complexity of the trimethylguanosine-capped, small nuclear rna (snrna) populations in a number of organisms has been examined using immunoprecipitation and two-dimensional gels. from the fungi aspergillus nidulans and schizosaccharomyces pombe, over 30 major snrnas can be resolved. the most abundant of these correspond to the putative analogues of vertebrate u1, u2, u4 and u5, which have been reported to be precipitated by anti-sm antibodies, but other snrnas are little less abundant than th ...19872958638
aspergillus nidulans beta-tubulin genes are unusually divergent.aspergillus nidulans has two beta-tubulin genes: bena, which is involved in both vegetative growth and asexual sporulation, and tubc, which is involved mainly in asexual sporulation. both genes have now been cloned and sequenced. bena encodes a polypeptide of 447 amino acids (aa) and tubc encodes one of 449 aa. the two polypeptides differ by 78 aa residues but the net charge for the two proteins remains the same. the divergence between the amino acid sequences of the aspergillus beta-tubulins is ...19872959591
induction of multiple germ tubes in neurospora crassa by antitubulin agents.the antitubulin fungicide benomyl suppressed the linear growth of neurospora crassa wild type strain st. lawrence 74 at micromolar concentrations. the rate of germination of macroconidia was not affected. macroconidia exposed to 1.7 microm benomyl for 5 h formed multiple germ tubes. when germlings incubated for 4 h were exposed to 1.7 microm benomyl for 3 h, their germ tube stopped growing, swelled and emitted several branches. normal linear growth was restored after removal of the fungicide. li ...19882969337
molecular cloning vectors for aspergillus and neurospora. 19882974737
comparison of the orotidine 5'-monophosphate decarboxylase sequences of eight species.predicted amino acid sequences of the enzyme orotidine 5'-phosphate decarboxylase (ec from eight different organisms are compared. the comparisons are made on the basis of primary structural differences, primary amino acid sequence, hydropathy profiles, and secondary structure predictions. the organisms compared are mus musculus, aspergillus nidulans, neurospora crassa, kluyveromyces lactis, saccharomyces cerevisiae, schizosaccharomyces pombe, escherichia coli, and salmonella typhimuri ...19882974823
aspergillus nidulans contains a single actin gene which has unique intron locations and encodes a gamma-actin.the single actin gene from the filamentous fungus aspergillus nidulans has been isolated and characterized. the only other organism reported to contain just one actin gene is another ascomycete, the budding yeast saccharomyces. the nucleotide sequence of the a. nidulans actin gene predicts a polypeptide containing the n-terminal sequence identifying the gamma-actin isotype. until now this characteristic n terminus has only been reported to occur in vertebrate actin sequences. a monospecific anti ...19882975248
molecular organisation of the quinic acid utilization (qut) gene cluster in aspergillus nidulans.the functional integrity of the qutb gene (encoding quinate dehydrogenase) has been confirmed by transformation of a qutb mutant strain. the dna sequence of the contiguous genes qutd (quinate permease), qutb and qutg (function unknown) has been determined and analysed, together with that of qute (catabolic 3-dehydroquinase). the qutb sequence shows significant homology with the shikimate dehydrogenase function of the complex arom locus of aspergillus nidulans, and with the qa-3 quinate dehydroge ...19882976880
cloning and characterization of the rdna repeat unit of podospora anserina.dna coding for ribosomal rna in podospora anserina has been cloned and was found as a tandemly repeated 8.3 kb sequence. the cloned rdna was characterized by restriction endonuclease mapping. the location of 5.8s, 18s and 28s rrna coding regions was established by dna-rna hybridization and s1 nuclease mapping. the organization of p. anserina rrna genes is similar to that of neurospora crassa and aspergillus nidulans. the rdna unit does not contain the sequence coding for 5s rna.19852987647
cloning of phosphoenolpyruvate carboxylase gene from a cyanobacterium, anacystis nidulans, in escherichia coli.the phosphoenolpyruvate carboxylase gene (ppc) from anacystis nidulans, a cyanobacterium (blue-green alga), was cloned in escherichia coli. chromosomal dna of a. nidulans was partially digested with sau3ai, and the obtained dna fragments were ligated in the bamhi site of pbr322. the hybrid plasmids were first transformed into e. coli k802 (hsdr-, hsdm+) to obtain the gene bank of a. nidulans. the bank consisted of about 12,000 clones. these hybrid plasmids were then transformed into e. coli pcr1 ...19852989256
helical packing in the hydrophobic sector of cytochrome c arrangement for the membrane-spanning segments of the three larger subunits of cytochrome c oxidase is proposed on the basis of sequence comparison and polarity distribution estimated from the data available for 11 different organisms.19852991455
direct and indirect gene replacements in aspergillus nidulans.we performed three sets of experiments to determine whether cloned dna fragments can be substituted for homologous regions of the aspergillus nidulans genome by dna-mediated transformation. a linear dna fragment containing a heteromorphic trpc+ allele was used to transform a trpc- strain to trpc+. blot analysis of dna from the transformants showed that the heteromorphic allele had replaced the trpc- allele in a minority of the strains. an a. nidulans trpc+ gene was inserted into the argb+ gene, ...19852991748
identification and molecular analysis of a third aspergillus nidulans alcohol dehydrogenase aspergillus nidulans functional cdna encoding an alcohol dehydrogenase (adh) was isolated by its ability to complement an adh1 mutation in saccharomyces cerevisiae. alignment of the cdna and cloned genomic dna sequences indicated that the adh gene contains two small introns. the presence of ethanol in the growth medium was shown to result in adh mrna accumulation presumably due to transcriptional induction of the gene. however, adh mrna accumulation was at most only partially repressed by the ...19852998782
nucleotide sequence of the phosphoenolpyruvate carboxylase gene of the cyanobacterium anacystis nidulans.nucleotide sequence of the open reading frame (orf) for the phosphoenolpyruvate carboxylase gene (ppc) of the cyanobacterium anacystis nidulans was determined. the orf consists of 3159 bp and codes for 1053 amino acid (aa) residues. the codon usage of the ppc of a. nidulans is not so markedly different from that of the escherichia coli ppc, yet, in a. nidulans the preferred codons are aag for lysine and ccc for proline, whereas those are seldom used in the e. coli ppc.19852998946
development of a high-frequency transforming vector for aspergillus nidulans.the pyr4 gene of neurospora crassa, which codes for orotidine-5'-phosphate decarboxylase, is capable of transforming an aspergillus nidulans pyrg mutant by chromosomal integration, despite low homology between the transforming dna and the recipient genome. integration of pfb6, a plasmid carrying pyr4 and capable of replication in escherichia coli, was not observed at the pyrg locus. the efficiency of transformation was considerably enhanced (50-100 fold) by inclusion in the transforming vector o ...19853000883
expression of an escherichia coli beta-galactosidase fusion gene in aspergillus nidulans.we inserted in frame the escherichia coli lacz gene into the protein-coding region of the aspergillus nidulans trpc gene and introduced the resultant fused gene into the a. nidulans genome. a functional beta gal fusion protein was produced. removal of the trpc transcription and translation initiation sequences from the fusion gene abolished production of the fusion protein, showing that expression is dependent on these sequences. thus, lacz fusions should be of use for estimating gene activity i ...19853005133
self-cloning in the cyanobacterium anacystis nidulans r2: fate of a cloned gene after reintroduction.functional analysis of cloned genes often makes use of complementation after introducing these genes into cells of a mutant strain. problems with this self-cloning step in the cyanobacterium anacystis nidulans r2 have been encountered, which were mainly due to recombinational instability of gene and vector after transformation. therefore, conditions determining the exchange of material between chromosome, insert and plasmids were studied to achieve the necessary stability. the fate of plasmid pm ...19853006100
transformation of aspergillus nidulans with a cloned, oligomycin-resistant atp synthase subunit 9 allele (olic31) of the a. nidulans olic gene has been cloned using homology with the equivalent gene from n. crassa. olic31 codes for an oligomycin-resistant, triethyltin-hypersensitive form of subunit 9 of the mitochondrial atp synthase complex. direct selection for oligomycin-resistance was possible following transformation of a. nidulans with the olic31 gene. the phenotypes of transformants cultured in the presence of oligomycin were indicative of the position of integration of the transfo ...19863010049
gene cloning in aspergillus nidulans: isolation of the isocitrate lyase gene (acud).an aspergillus nidulans gene library was constructed in a high-frequency transformation vector, pdjb3, based on the neurospora crassa pyr4 gene. this gene library was used to isolate the structural gene for isocitrate lyase (acud) by complementation of a deficiency mutation following transformation of a. nidulans. plasmids rescued in escherichia coli were able to transform five different a. nidulans acud mutants. transformation using plasmids containing the cloned fragment resulted in integratio ...19863010050
endogenous energy supply to the plasma membrane of dark aerobic cyanobacterium anacystis nidulans: atpase-independent efflux of h+ and na+ from respiring cells.the ejection of protons from oxygen-pulsed cells and the gradients of na+ concentration (na+o/na+i at 150 mm external nacl) and proton electrochemical potential (delta mu h+) across the plasma membrane of anacystis nidulans were studied in response to dark endogenous energy supply. saturating concentrations of the f0f1-atpase inhibitors dicyclohexylcarbodiimide (f0) and 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (f1) eliminated oxidative phosphorylation and lowered the atp level from 2.6 +/- 0.15 to ...19863010878
structural genes for phosphatases in aspergillus nidulans. 19863011590
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