TitleAbstractYear(sorted ascending)
growth characteristics of aspergillus nidulans mutans defective in carbohydrate metabolism.several mutants aspergillus nidulans defective in carbohydrate metabolism were tested for growth on different carbon sources. d-galacturonate was found to be a substrate, useful to discriminate between mutants in pyruvate kinase, pyruvate dehydrogenase complex or pyruvate carboxylase. the results of these tests indicate how particular classes of mutants can be obtained and which substrates can be used preferentially for a rapid phenotypical screening of unknown mutants.19826751221
isoelectric focusing and two-dimensional analysis of purified nitrate reductase from aspergillus nidulans.the assimilatory nadph-nitrate oxidoreductase (ec from aspergillus nidulans was purified by means of affinity chromatography and analyzed by agarose isoelectric focusing and two-dimensional electrophoresis. nadph-nitrate reductase activity was not activated by oxidation with potassium ferricyanide and was irreversibly inhibited by acrylamide. electrophoresis of nitrate reductase in 7% polyacrylamide gels resulted in rapid loss of enzyme activity. isoelectric focusing of purified enzyme ...19826751405
mitochondrial l-rrna from aspergillus nidulans: potential secondary structure and evolution.the alignment of gene sequences coding for a. nidulans mitochondrial l-rrna and e. coli 23s rrna indicates a strong conservation of primary and potential secondary structure of both rrna molecules, except that homologies to the 5'-terminal 5.8s-like region and the 3'-terminal 4.5s-like region of bacterial rrna are not detectable on mtdna. the structural organization of the a. nidulans mt l-rrna gene corresponds to that of yeast omega + strains: both genes are interrupted by a large intron sequen ...19826752884
the regulation of urease activity in aspergillus nidulans.aspergillus nidulans can utilize urea as a sole source of nitrogen but not as a carbon source. urea is degraded by a urease. mutation at any one of three genes, ureb, urec, and ured, may result in deficient urease activity. the ureb gene is closely linked to urea, the structural gene for the urea transport protein. the heat lability of ureb- revertant strain, intragenic complementation tests, and the linkage of ureb to urea suggest that ureb is the urease structural gene. the ured gene is probab ...19826753831
internal structure of a mitochondrial intron of aspergillus nidulans.the intron of the mitochondrial apocytochrome b gene, coba, of aspergillus nidulans has been subjected to sequence analysis. it contains an open reading frame of 957 base pairs contiguous with the preceding exon. regions of the translated open reading frames of coba and the third intron of the cob gene in yeast show high amino acid homology. comparison of the coba intron with this and other yeast introns indicates that coba codes for a maturase protein that splices out the intron encoding it and ...19826755468
making ends meet: a model for rna splicing in fungal mitochondria.on the basis of available nucleotide sequence and genetic data; we present a model for rna splicing in fungal mitochondria. seven intron rnas of two fungal species can form identical secondary structures, involving four conserved sequences, which bring the ends of each intron together and allow an internal guide rna sequence to pair with exon bases adjacent to the splice junctions. the splicing sites are thus aligned precisely within a conserved structure, which we suggest could present specific ...19826757759
a cis-dominant mutation in aspergillus nidulans affecting the expression of the amds gene in the presence of mutations in the unlinked gene, amda.a mutant producing very high levels of the acetamidase enzyme encoded by the amds gene has been isolated in a strain containing the amda7 mutation, which itself causes high levels of this enzyme. genetic analysis has shown that this mutation, designated amdi66, is adjacent to the amds gene and is cis-dominant in its effect. the amdi66 mutation has little effect on amds expression when present in strains not containing the amda7 mutation. two other amda mutations investigated also interact with t ...19826759305
studies on air-borne fungi at qena. iii. thermophilic fungi. 19826759940
meiosis in aspergillus nidulans: another example for lacking synaptonemal complexes in the absence of crossover interference. 19826761318
a near terminal pericentric inversion leads to nitrogen metabolite derepression in aspergillus nidulans.the mutation xprd-1, previously shown to be an allele of the area gene and to lead to nitrogen metabolite derepression in aspergillus nidulans, is shown to be associated with a near terminal pericentric inversion in linkage group iii. the left arm break-point is between the adi and sc genes, and the right arm break-point is between the ornc and area genes but just centromere proximal to area. in crosses of xprd-1 strains to inversion-free strains one class of duplication-deficiency progeny is re ...19826761550
in vitro mutational studies with trifluralin and trifluorotoluene derivatives. 19826763485
modification of chromosome instability in aspergillus nidulans.strains of aspergillus nidulans with a chromosome segment in duplicate show instability at mitosis; their colonies produce faster-growing sectors which arise from nuclei with spontaneous deletions in either duplicate segment. in an attempt to probe the deletion process, the effects of mutations causing sensitivity to uv treatment, and those of manganous ions, have been studied in strains carrying either dp(i,ii) or dp(iii,viii). for comparison, the effects of mn2+ on balanced and unbalanced dipl ...19826763939
clustering of spore-specific genes in aspergillus nidulans.we have investigated the chromosomal organization of genes that are expressed specifically in the asexual spores (conidia) of the ascomycete fungus aspergillus nidulans, using two experimental approaches. in the first, 30 different recombinant clones, containing long nuclear dna inserts and at least one spore-specific gene, were selected randomly. the total number of spore-specific genes present in each clone was then determined by rna blot analysis. in the second approach, several chromosomal r ...19826764535
l-histidine utilization in aspergillus nidulans.histidase activity rather than uptake of l-histidine is the limiting factor for the utilization of histidine as the sole nitrogen source for aspergillus nidulans. histidine cannot act as the sole carbon source, and evidence is presented indicating that this is attributable to an inability to convert histidine to l-glutamate in vivo. it has been shown that this fungus lacks an active urocanase enzyme and that histidine is quantitatively converted to urocanate, which accumulates in the extracellul ...19826120926
the regulation of nadp-linked isocitrate dehydrogenase in aspergillus nidulans.the regulation of nadp-linked isocitrate dehydrogenase (nadp-idh) has been studied in wild-type and mutant strains of aspergillus nidulans. in the wild-type strain studied, the levels of nadp-idh vary in a similar way to those of acetamidase, acetyl-coa synthase, isocitrate lyase and malate synthase under all growth conditions used. similarly, fac mutants, which are altered in the regulation of these enzymes of acetate utilization, are affected in nadp-idh levels in a parallel fashion, as are cr ...19826123545
intron within the large rrna gene of n. crassa mitochondria: a long open reading frame and a consensus sequence possibly important in splicing.we describe the sequence of the 2295 nucleotide long intron and 245 nucleotides of the flanking exon sequences within the large (24s) rrna gene of neurospora crassa mitochondria. the intron contains a long open reading frame, which could correspond to ribosomal protein s5. comparison with the corresponding intron of the large rrna gene of yeast mitochondria reveals a single highly homologous 57 nucleotide long sequence, including the sequence (formula; see text), which is present in virtually al ...19826218884
cell wall degradation in the autolysis of filamentous fungi.a systematic study on autolysis of the cell walls of fungi has been made on neurospora crassa, botrytis cinerea, polystictus versicolor, aspergillus nidulans, schizophyllum commune, aspergillus niger, and mucor mucedo. during autolysis each fungus produces the necessary lytic enzymes for its autodegradation. from autolyzed cultures of each fungus enzymatic precipitates were obtained. the degree of lysis of the cell walls, obtained from non-autolyzed mycelia, was studied by incubating these cell ...19826219290
the effect of the synergy between sterigmatocystin and a fungal metabolite on bacillus subtilis. 19826175614
recombinogenic and mutagenic effects of the antitumor antibiotic bleomycin in aspergillus nidulans.bleomycin, an antibiotic and antineoplastic drug that inhibits dna synthesis and causes several types of chromosomal aberration, was found to increase mitotic recombination in aspergillus nidulans. heterozygous prototrophic diploid strains grown on media containing bleomycin produced significant increases of yellow and white sectors compared with controls. further, the increased colour segregants were due to mitotic crossing-over, whereas the non-dis junctional segregants remained at the control ...19826181398
dna sequence of the region adjacent to the oxi1 and oxi2 genes from aspergillus nidulans mitochondrial dna. 19826184922
effect of alpha-amanitin and actinomycin d on rna synthesis in the protoplasts of aspergillus nidulans.rna synthesis was studied in protoplasts from aspergillus nidulans, which remained metabolically active for several days under the appropriate conditions. it is concluded, that at certain actinomycin d concentrations the ribosomal rna synthesis can be selectively inhibited. however, alpha-amanitin at concentrations up to 400 micrograms/ml neither influenced the total nor the rna polymerase ii directed rna synthesis. it was possible to discriminate between the rna polymerase i or ii directed rna ...19826186893
mitotic aneuploidy induced by sodium deoxycholate in aspergillus nidulans.sodium deoxycholate is shown to induce aneuploidy in a heterozygous diploid strain of aspergillus nidulans. it is suggested that this is the result of interference with the normal functioning of the mitotic apparatus through disruption of the nuclear membrane. this effect limits the value of sodium deoxycholate as a paramorphogenic agent in the estimation of the genotoxic effects of environmental and genetic factors.19827038466
aspergillus nidulans: systems and results of tests for chemical induction of mitotic segregation and mutation. i. diploid and duplication assay systems. a report of the u.s. epa gene-tox program. 19827038472
aspergillus nidulans: systems and results of tests for induction of mitotic segregation and mutation. ii. haploid assay systems and overall response of all systems. a report of the u.s. epa gene-tox program. 19827038473
hydrolysis of vegetable oils and triglycerides by thermotolerant and zoopathogenic species of aspergillus from nigerian palm produce.the ability of aspergillus fumigatus fres. and aspergillus nidulans (eidam) wint obtained from nigerian palm produce to degrade vegetable oils and triglycerides and the production and activity of their extracellular lipases were studied. both species readily hydrolysed palm oil and palm kernel oil among others liberating free fatty acids in the process. good growth with mycelia production of both fungi were also recorded on the triglycerides used as sources of carbon at 37 degrees c with the bes ...19827040975
purification and characterization of the assimilatory nadph-nitrate reductase of aspergillus nidulans.nadph-nitrate reductase [nadph : nitrate oxidoreductase, ec] was purified 500-fold from aspergillus nidulans with an overall yield of about 20%. the purified enzyme catalyzed nadph-nitrate, nadph-cytochrome c, fadh2-nitrate and reduced methyl viologen-nitrate reductase activities. its molecular weight was estimated to be 180,000 from the stokes radius and sedimentation coefficient. the oxidized enzyme exhibited an absorption spectrum having a peak at 412 nm and a broad shoulder at about ...19827042701
polyamine transport in aspergillus nidulans.the uptake of putrescine, spermidine and spermine was studied in aspergillus nidulans using 14c-labelled polyamines. active transport systems, inhibited by azide and regulated by nitrogen availability, exist at least for putrescine and spermidine. putrescine is taken up two to three times more rapidly than spermidine, reflecting a lower km for the former substrate. the two uptake systems appear to be independent, spermidine uptake being inhibited by both putrescine and spermine, while putrescine ...19827042908
[genetic control of recombination processes in aspergillus nidulans. iv. the effect of uvs mutations on the frequency of spontaneous and nitrosomethylurea-induced intragenic mitotic recombination].effects of three uvs mutations were studied on spontaneous and nitrosomethyl-induced intragenic mitotic segregation in the metha region of the chromosome ii in aspergillus diploids homozygous for uvs and heteroallelic for metha mutation. the reversion frequencies of metha alleles in parent haploid strains were also determined. all the mutations increased the frequency of spontaneous and decreased that of induced intragenic mitotic recombination. the frequency of spontaneous reversions was decrea ...19827047300
genetical and biochemical aspects of quinate breakdown in the filamentous fungus aspergillus the ascomycetous fungus aspergillus nidulans, the expression of two inducible, contiguous or closely linked genes (qutb and qutc) which encode enzymes for quinate breakdown to protocatechuate, appears to be controlled by the product of a tightly linked third genet (quta). the qut gene cluster locates on chromosome viii. the catalytic steps required for this conversion are dehydrogenase, dehydroquinase, and dehydratase, and these activities are induced by the presence of quinate in a similar m ...19827049157
positive regulation in a eukaryote, a study of the uay gene of aspergillus nidulans: i. characterization of alleles, dominance and complementation studies, and a fine structure map of the uay--oxpa this paper we characterize genetically a positive eukaryotic regulatory gene: the uay gene of the ascomycete aspergillus nidulans. several steps in the uptake and degradation of purines are under the control of the uay gene (summarized in scazzocchio and gorton 1977). in the present paper 12 uay-mutations are characterized with respect to their inducibility for adenine deaminase, xanthine dehydrogenase (purine hydroxylase i) and urate oxidase and by the absence of the uric acid-xanthine perme ...19827049832
purification and characterization of the conidial laccase of aspergillus nidulans.conidial laccase of aspergillus nidulans was purified by standard protein purification methods. although the purified material showed a cluster of several protein bands on a nondenaturing gel, each of these protein bands had laccase activity. all bands of activity, however, were absent in a strain carrying a mutation in the structural gene for laccase. concentrated solutions (greater than 1 mg/ml) were bright blue, suggesting that, like other laccases, this enzyme contains copper. the enzyme con ...19827050088
ergosterol and lanosterol from aspergillus nidulans.ergosterol was identified as the major free sterol of aspergillus nidulans by thin-layer chromatography, alumina column chromatography, gas-liquid chromatography, high-performance liquid chromatography, uv spectroscopy, proton magnetic resonance spectroscopy and mass spectral analysis. lanosterol, the initial cyclized precursor of ergosterol, was identified as a minor component of the free sterols. in the steryl ester material, however, lanosterol was usually more abundant than ergosterol, sugge ...19827050295
a possible regulatory gene for the molybdenum-containing cofactor in aspergillus nidulans.aspergillus nidulans has three molybdoenzymes, nitrate reductase, purine hydroxylase i and purine hydroxylase ii. these three enzymes share a molybdenum-containing cofactor whose synthesis requires the integrity of five loci, designated cnxabc, cnxe, cnxf, cnxg and cnxh. here we report the existence of a sixth locus, designated cnxj, which might be involved inthe regulation of cofactor levels. when grown in the presence, but not in the absence, of tungstate or methylammonium, strains carrying cn ...19827050297
molecular and genetic methods for studying mitosis and spindle proteins in aspergillus nidulans. 19827050618
metabolism of 5'-methylthioadenosine in aspergillus nidulans. an alternative pathway for methionine synthesis via utilization of the nucleoside methylthio group.experiments in which 5'-methylthioadenosine was used as a culture supplement for methionine-requiring mutants of aspergillus nidulans with various enzymatic lesions indicated that the methylthio group derived from the nucleoside can be recycled to methionine. the results strongly suggest that methionine may be synthesized in the reaction catalyzed by homocysteine synthase (ec in which o-acetylhomoserine is an acceptor of the methylthio group. the first step on the salvage pathway of t ...19827052140
aspergillus nidulans as a test organism for chemical the 3 strains of aspergillus nidulans used, bc reduced survival most and 4hmb least. similar trends were found when the effect on gene conversion was studied in a diploid strain and point mutation was scored in a haploid strain. none of the compounds had any effect on mitotic segregation.19827035880
testing for mitotic crossing over and induced aneuploidy using aspergillus nidulans as part of the ukems test programme. 19827035881
nitrogen metabolite repression in aspergillus nidulans: a farewell to tama?previous work has established that nitrogen metabolite repression in aspergillus nidulans is mediated by the positive acting regulatory gene area. pateman and kinghorn (1977) proposed that the gene tama plays an equally important regulatory role in nitrogen metabolite repression as the result of work with "tama(r)-50," an "allele" leading to inability to utilise nitrogen sources other than ammonium, and "tama(d)-1," an "allele" leading to nitrogen metabolite derepression. both "tama(r)-50" and " ...198224186552
a single mutation leads to loss of glutamine synthetase and relief of ammonium repression in aspergillus.glutamine synthetase activity in the ascomycete fungus aspergillus nidulans is regulated by nitrogen source. the lowest activities are obtained when the fungus is grown on l-glutamine, and the highest activities when grown on l-glutamate + arabinose. glutamine auxotrophs of the fungus have been isolated, and one of these mutant strains, glna-1, has been shown to lack the enzyme glutamine synthetase. the mutation is recessive, and is located on the right arm of chromosome ii. in addition to aboli ...198224186546
domain-wide, locus-specific suppression of nitrogen metabolite repressed mutations in aspergillus nidulans.previous work has shown that loss of function mutations (designated are a(r)) in area, a positive acting regulatory gene mediating nitrogen metabolite repression in aspergillus nidulans, lead to inability to utilise nitrogen sources other than ammonium. this work establishes the existence of a gene designated areb where mutations can suppress area(r) mutations in a locus-specific manner for expression of apparently all of the genes under area control. areb mutations are partially dominant in dip ...198224186375
genetic map of mitochondrial dna in podospora order to develop an eukaryotic vector with the podospora plasmid, further characterization is required of the mitochondrial dna into which this plasmid is integrated, a physical map (restriction sites) of the podospora chondriome (size 95 kb) has been completed. as prerequisite for the establishment of a genetic (functional) map, 70% of the chondriome was cloned in e. coli vectors. using mitochondrial genes from saccharomyces cerevisiae, six structural genes were located on the podospora chon ...198224186230
chilling-susceptibility of the blue-green alga anacystis nidulans: iii. lipid phase of cytoplasmic membrane.the lipid phase of cytoplasmic membrane was studied by freeze-fracture electron microscopy in the chilling-susceptible blue-green alga, anacystis nidulans. at growth temperatures, intramembrane particles were distributed at random in the fracture faces of cytoplasmic membrane, whereas, at chilling temperatures, the fracture faces were composed of particle-free and particle-containing regions. these findings indicate that lipids of the cytoplasmic membrane were in the liquid-crystalline state at ...198216662143
molecular cloning and sequence analysis of the cyanobacterial gene for the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase.ribulose-1,5-bisphosphate carboxylase/oxygenase consists of large subunits (ls) and small subunits. in plants, the ls is encoded in chloroplast dna and the small subunit, in nuclear dna. in cyanobacteria, both subunits are thought to be encoded in chromosomal dna because of prokaryotes. the gene for the ls of ribulose-1,5-bisphosphate carboxylase/oxygenase from a cyanobacterium, anacystis nidulans 6301, has been cloned in pbr322 and subjected to sequence analysis. the coding region contains 1,41 ...198316593333
mitochondrial four-point crosses in aspergillus nidulans : mapping of a suppressor of a mitochondrially inherited cold-sensitive mutation.four-point mitochondrial crosses were conducted in heterokaryons of aspergillus nidulans. the mutations used were (olia1), conferring resistance to oligomycin, (cama112), conferring resistance to chloramphenicol; (cs-67), conferring cold-sensitivity, and ( sumd16), a suppressor of (cs-67). initially, the crosses were conducted by observing the segregation of extranuclear markers in heterokaryotic sectors emerging from the original point of heterokaryosis. this showed that (cama112), (cs-67) and ...198317246113
the mitochondnal genome of aspergillus nidulans contains reading frames homologous to the human urfs 1 and 4.a 2830-bp segment of the mitochondrial genome of the fungus aspergillus nidulans was sequenced and shown to contain two unidentified reading frames (urfs). these reading frames are 352 and 488 codons in length, and would specify unmodified proteins of mol. wts. 39,000 and 54,000, respectively. the derived amino acid sequences indicate that these genes are equivalent to the human mitochondrial urfs 1 and 4, with 39% amino acid homology for urf1 and 26% for urf4. both urfs were shown by secondary ...198311894959
transcription of the rrna gene cluster in aspergillus nidulanss.transcription of rdna in aspergillus nidulans was examined by hybridizing labeled cloned rdna fragments to blots of rna gels. one processing pathway was found.198324173152
nucleotide sequence and intron structure of the apocytochrome b gene of neurospora crassa mitochondria.the sequence of the apocytochrome b (cob) gene of neurospora crassa has been determined. the structural gene is interrupted by two intervening sequences of approximately 1260 bp each. the polypeptide encoded by the exons shows extensive homology with the cob proteins of aspergillus nidulans and saccharomyces cerevisiae (79% and 60%, respectively). the two introns are, however, located at sites different from those of introns in the cob genes of a. nidulans and s. cerevisiae (which contain highly ...198310872314
development of fluorescent-antibody reagents for demonstration of pseudallescheria boydii in tissues.we prepared fluorescent-antibody reagents to detect and identify pseudallescheria boydii in tissue. antisera to broken mycelium and condidia (particulate antigens) and to culture filtrates (soluble antigens) of p. boydii were produced in rabbits. antisera and globulin fractions of the antisera were labeled with fluorescein isothiocyanate and evaluated for their ability to stain p. boydii in tissues. the conjugates were first tested with cultures of 25 p. boydii isolates and 26 heterologous fungi ...19836195179
high-frequency conversion to a "fluffy" developmental phenotype in aspergillus spp. by 5-azacytidine treatment: evidence for involvement of a single nuclear gene.transient exposure of mycelia from aspergillus niger and aspergillus nidulans to the cytidine analog 5-azacytidine, leading to no more than 0.3 to 0.5% substitution for cytosine by 5-azacytosine in a. nidulans dna, resulted in the conversion of a high fraction of the cell population (more than 20%) to a mitotically and meiotically stable "fluffy" developmental phenotype. the phenotypic variants are characterized by the developmentally timed production of a profuse fluffy network of undifferentia ...19836197627
cloning of aspergillus nidulans ribosomal dna in shotgun experiments using the ek2 vector lambda gtwest.t5-622.ecori fragments of aspergillus nidulans dna were cloned in a shotgun type experiment using the ek2 vector lambda gtwest.t5-622. in situ plaque hybridization was used to screen for hybrid phage particles containing sequences coding for ribosomal rna. four clones selected from the whole gene bank were characterized further. two of them contain sequences homologous to a 3.6 kb fragment of a. nidulans rdna.19836198874
transformation of aspergillus nidulans by the orotidine-5'-phosphate decarboxylase gene of neurospora crassa.relief of an auxotrophic requirement for uridine in aspergillus nidulans strain g191 has been achieved by transformation with a segment of neurospora crassa dna containing the corresponding gene coding for orotidine-5'-phosphate decarboxylase. the mitotic stability of such transformants suggests that the dna has integrated into the genome. southern hybridisation analysis of dna isolated from transformants revealed the presence of pbr322 sequences which have integrated into the host genome along ...19836220717
regulation of alcohol dehydrogenase (adh) and aldehyde dehydrogenase (alddh) in aspergillus nidulans. 19836132393
isolation of beta-amyrin from the fungus aspergillus nidulans.the pentacyclic triterpene alcohol beta-amyrin, which is commonly found in plants, was isolated from wild-type cultures of the ascomycete fungus aspergillus nidulans. the isolated beta-amyrin was characterized by tlc, glc, and hplc and produced identical mass and 1h nmr spectra to those of authentic beta-amyrin. this material was isolated from static (non-shaking) cultures.19836875511
different biosynthetic pathways of the pyrimidine moiety of thiamin in procaryotes and eucaryotes.[14c]formate is incorporated into the c-2 of the pyrimidine moiety of thiamin by escherichia coli and salmonella typhimurium. in saccharomyces cerevisiae, it is incorporated into c-4. radioactive carbons of [1-14c]glycine and [2-14c]glycine are incorporated by s. typhimurium into the c-4 and c-6 of the pyrimidine, respectively, but not by s. cerevisiae. these facts suggest that procaryotes and eucaryotes have different biosynthetic pathways for pyrimidine. in this study, the procaryotes tested i ...19836218832
production of 2'-deoxycoformycin by the fungus emericella nidulans and its inhibitory effect on adenosine deaminase.isolation and characterization of 2'-deoxycoformycin from the culture filtrate of the fungus emericella nidulance is described. its inhibitory effect on adenosine deaminase (ada, adenosine aminohydrolase, ec is also described.19836607458
[characteristic features of protoplast formation and regeneration in fusidium coccineum].the methods for preparation and regeneration of protoplasts were tested with respect to the strains of f. coccineum markedly differing in their capacity for antibiotic production, sporulation and the growth rate. it was found that the substrate used for the culture growth had a significant effect on the cell wall and sensitivity of the mycelium to lytic enzymes. an enzyme from hellix pomatia and its combination with lysozyme were used for lysing the culture. the cytological investigation of the ...19836404216
structure of oxidized flavodoxin from anacystis nidulans.the structure of oxidized flavodoxin from the cyanobacterium anacystis nidulans has been determined at 2.5 a resolution with phases calculated from ethylmercury phosphate and dimercuriacetate derivatives. the determination of partial sequences, including a total of 85 residues, has assisted in the interpretation of the electron density. preliminary refinement of a partial model (1072 atoms) has reduced r to 0.349 for the 10.997 reflections between 2.0 and 5.0 a with 1 greater than 2 sigma. the p ...19836406674
determination of the sequence which spans the beginning of the insertion region in anacystis nidulans flavodoxin.anacystis nidulans flavodoxin is one of the long chain flavodoxins (mayhew & ludwig, 1975). comparisons of its structure with the structures of shorter chain species (main text: ludwig et al., 1982) show that in a. nidulans flavodoxin most of the extra residues occupy a region adjoining the third helix and the fifth strand of parallel sheet. the sequences of peptides isolated after cyanogen bromide cleavage and after digestion with staphylococcus aureus protease, reported here, fit into the elec ...19836406675
drift in ultraviolet sensitivity and expression of mutations during synchronous growth of cyanobacterium anacystis nidulans.synchrony with respect to cell division and dna synthesis in cultures of anacystis nidulans was induced by a light-dark-light regimen. at periodic intervals in the cell-division cycle, dna, rna, protein contents, uv sensitivity and induction of mutations were assayed. the dna, rna and protein syntheses were periodic and reached maximal values before the separation of cells. the dna content started to increase at about the 5th hour and doubled at about the 13th hour followed by a plateau of 4-6 h ...19836408466
the isocitrate dehydrogenase from cyanobacteria.the present communication describes the properties of isocitrate dehydrogenase in crude extracts from the unicellular anacystis nidulans and from heterocysts and vegetative cells of nostoc muscorum and anabaena cylindrica. the activity levels of this enzyme are much higher in heterocysts than in vegetative cells of n. muscorum and a. cylindrica. isocitrate dehydrogenase is virtually inactive in vegetative cells of a. cylindrica. the enzyme is negatively regulated by the reduction charge and scar ...19836409049
effects of mn2+, ca2+ and chlorpromazine on photosystem ii of anacystis nidulans. an attempt to establish a functional relationship of amino acid oxidase to photosystem ii.washing with edta changes the specificity of anacystis nidulans particles having photosystem ii activities for activation by cations. a specific requirement for mn2+ and a somewhat lower specificity for ca2+ can be demonstrated in the edta-washed particles. both ions must be added to reconstitute the system evolving o2 in the light. edta-washed particles retain the l-amino acid oxidase with high specificity for the basic l-amino acids [pistorius, e. k. and voss, h. (1980) biochem. biophys. acta, ...19836411470
the complete nucleotide sequence of a 16s ribosomal rna gene from a blue-green alga, anacystis nidulans.the complete nucleotide sequence of a 16s ribosomal rna gene from a blue-green alga, anacystis nidulans, has been determined. its coding region is estimated to be 1,487 base pairs long, which is nearly identical to those reported for chloroplast 16s rrna genes and is about 4% shorter than that of the escherichia coli gene. the 16s rrna sequence of a. nidulans has 83% homology with that of tobacco chloroplast and 74% homology with that of e. coli. possible stem and loop structures of a. nidulans ...19836412038
an evaluation of the mutagenic, carcinogenic and teratogenic potential of microwaves.a notable proportion of the population is exposed to an increasing number of devices emitting microwaves, a form of non-ionizing electromagnetic radiation in the range 300-30000 mhz. the activation energy of microwave radiations is too small to directly modify any chemical bonds in the irradiated matter. at microwave frequencies the macroscopic dielectric properties of tissues are strongly determined by their water content. tissues like muscle, brain, skin, with a high water content, have higher ...19836412137
mycologic identification of emericella nidulans and aspergillus flavus causing pulmonary infection. 19836413149
the gene for the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase is located close to the gene for the large subunit in the cyanobacterium anacystis nidulans 6301.the gene for the small subunit (ss) of ribulose-1,5-bisphosphate carboxylase/oxygenase from a cyanobacterium, anacystis nidulans 6301, has been cloned and subjected to sequence analysis. the ss coding region is located close to and downstream from the large subunit (ls) coding region on the same dna strand. the spacer region between the ls and the ss coding regions contains 93 base pairs (bp), and has no promoter-like sequences. the coding region of a. nidulans ss gene contains 333 bp (111 codon ...19836415615
the complete nucleotide sequence of a 23s rrna gene from a blue-green alga, anacystis nidulans.the complete nucleotide sequence of a 23s rrna gene from a blue-green alga, anacystis nidulans, has been determined. this nucleotide sequence has 78% and 68% homologies with those of the tobacco chloroplast and escherichia coli 23s rrna genes, respectively. the 3'-terminal region of the a. nidulans 23s rrna gene has strong homology with the chloroplast 4.5s rrna.19836416928
a new hybrid plasmid capable of transforming escherichia coli and anacystis nidulans.we have constructed a hybrid plasmid, pdf30, by combining the 8-kb pdf3 plasmid derived from the cyanobacterium anacystis nidulans 6311 with the escherichia coli vector pbr325. pdf30 transforms, replicates and confers chloramphenicol resistance (cmr) and ampicillin resistance (apr) on both a. nidulans and e. coli. the level of resistance to ampicillin in a. nidulans transformants, although low, is above background resistance and an apr activity was demonstrated in cell-free extracts of a. nidula ...19836307827
a hybrid plasmid is a stable cloning vector for the cyanobacterium anacystis nidulans r2.anacystis nidulans r2 is a highly transformable strain which is suitable as a recipient for molecular cloning in cyanobacteria. in an effort to produce an appropriate cloning vector, we constructed a hybrid plasmid molecule, psg111, which contained pbr328 from escherichia coli and the native puh24 plasmid of a. nidulans. psg111 replicated in and conferred ampicillin and chloramphenicol resistance to both hosts. it contained unique sites for the restriction enzymes ecori, sali, sphi, and xhoi, wh ...19836309751
shuttle cloning vectors for the cyanobacterium anacystis nidulans.hybrid plasmids capable of acting as shuttle cloning vectors in escherichia coli and the cyanobacterium anacystis nidulans r2 were constructed by in vitro ligation. dna from the small endogenous plasmid of a. nidulans was combined with two e. coli vectors, pbr325 and pdpl13, to create vectors containing either two selectable antibiotic resistance markers or a single marker linked to a flexible multisite polylinker. nonessential dna was deleted from the polylinker containing plasmid pplan b2 to p ...19836311795
a host-vector system for gene cloning in the cyanobacterium anacystis nidulans r2.we describe the construction of a series of vectors suitable for gene cloning in the cyanobacterium anacystis nidulans r2. from the indigenous plasmid puh24, derivatives were constructed with streptomycin as the selective marker; one of these plasmids was used to construct puc303, a shuttle vector capable of replication in a. nidulans r2 as well as in escherichia coli k12. it has two markers, streptomycin and chloramphenicol resistance, and three unique restriction sites. instability of recombin ...19836314409
distinction between cofactor-dependent and -independent phosphoglycerate mutases by chromatography on cibacron blue-sepharose.the binding of phosphoglycerate mutases from a variety of sources to cibacron blue-sepharose has been examined. those enzymes which are dependent on 2,3-bisphosphoglycerate (bpg) for activity bind to the immobilized dye and can be eluted by bpg. those enzymes which are independent of bpg do not bind to the immobilized dye. the possible structural significance of this distinction is discussed.19836315103
developmental regulation of the aspergillus nidulans trpc gene.we have cloned the trifunctional trpc gene from aspergillus nidulans by hybrid phage lambda complementation of an escherichia coli trpc mutant lacking phosphoribosylanthranilate isomerase activity. four different phages sharing a 4.3-kilobase region were obtained. plasmid subclones containing this region also complemented the e. coli trpc mutant. we determined that a 1.8-kilobase dna fragment was minimally required for complementation. the fragment hybridized with two poly(a)+ rnas, 3.0 and 3.2 ...19836324178
induced mutation developing delta 9-desaturase defective unsaturated fatty acid requiring mutants of aspergillus nidulans imi 72731. 19836365749
the location and analysis of two heterokaryon incompatibility (het) loci in strains of aspergillus nidulans.the heterokaryon incompatibility system in aspergillus nidulans has been investigated by parasexual methods. the use of complementary auxotrophs with a repeated serial transfer method or with a protoplast fusion technique has enabled heterokaryons and diploid strains to be recovered from heterokaryon incompatible combinations of strains. the effects of allelic interaction at heterokaryon incompatibility (het) loci on the morphologies of the heterokaryon and diploid colonies isolated are describe ...19836366116
a chromosome assay method for the detection of heterokaryon incompatibility (het) genes operating between members of different heterokaryon compatibility (h-c) groups in aspergillus nidulans.protoplast fusion has made possible the isolation of a diploid strain from haploid parents belonging to heterokaryon compatibility (h-c) groups q and gl of aspergillus nidulans. this diploid was not fully heterokaryon compatibility tests conducted between selected pairs of parasexually derived progeny strains facilitated a chromosome assay method for the detection of heterokaryon incompatibility (het) genes. despite the lack of segregation for the linkage group vi marker, it proved possible to l ...19836366117
transformation by integration in aspergillus nidulans.dna-mediated genetic transformation of aspergillus nidulans has been achieved by incubating protoplasts from a strain of a. nidulans carrying a deletion in the acetamidase structural gene with dna of derivatives of plasmid pbr322 containing the cloned structural gene for acetamidase [hynes et al., mol. cell. biol. 3 (1983) 1430-1439; p3sr2] in the presence of polyethylene glycol and cacl2. the highest frequency obtained was 25 transformants per microgram of dna. no enhancement of the transformat ...19836368319
proton pump coupled to cytochrome c oxidase in the cyanobacterium anacystis nidulans.intact spheroplasts of the cyanobacterium anacystis nidulans were found to oxidize various exogenous c-type cytochromes with concomitant proton extrusion. in the coupled state, h+/e stoichiometries close to 1 were measured, regardless of absolute reaction rates. it is concluded that the proton translocation observed is an intrinsic property of the cytoplasmic membrane-bound cytochrome c oxidase of a. nidulans.19836294060
a mutation in aspergillus nidulans that blocks the transition from interphase to order to develop a method for obtaining mitotic synchrony in aspergillus nidulans, we have characterized previously isolated heat-sensitive nim mutations that block the nuclear division cycle in interphase at restrictive temperature. after 3.5 h at restrictive temperature the mitotic index of a strain carrying one of these mutations, nima5, was 0, but when this strain was subsequently shifted from restrictive to permissive temperature the mitotic index increased rapidly, reaching a maximum of ...19836339527
detection of a proteinase inhibitor in aspergillus nidulans.the activity of proteinases in mycelial extracts of aspergillus nidulans increased during storage. the rate of activation increased with temperature. three separate proteinase activities, differing in their electrophoretic mobilities on polyacrylamide gels, were readily detected at ph 6.5. inhibitory activity, effective against all three proteinase activities, was also detected in fractions prepared from fresh mycelial extracts. the inhibitory factor(s) were heat-stable and non-dialysable. the i ...19836339674
dna duplication has resulted in transfer of an amino-terminal peptide between two mitochondrial proteins.the mitochondrial genome of the ascomycete aspergillus nidulans possesses at least nine unidentified reading frames (urfs). two of these are particularly interesting in that the amino acid sequences of the derived translation products are very similar in the n-terminal regions. the first 36 residues of the urfx gene product are repeated at the start of a second reading frame, urfa3, with only six mismatches. despite this similarity in their amino-termini, the latter parts of urfx and urfa3 are c ...19836339955
[lethal and mutagenic action of solar radiation on model microbiological test systems].lethal, mutagenic and recombonogenic action of the solar radiation on the model microorganisms--phage t4, bacteria escherichia coli and ascomycet aspergillus nidulans--has been studied. a considerable lethal effect of the solar radiation on phage t4 and e. coli was found. an increasing of mutation frequency in e. coli and a. nidulans by sunlight was also revealed. recombinogenic action of solar radiation has been demonstrated in the experiments with diploid a. nidulans strains. it was shown that ...19836340743
diagnosis of nonsense mutations in aspergillus nidulans.three genotypically suppressible alleles, a1x4, alca125, and niad500, are phenotypically suppressed by aminoglycoside antibiotics. unsuppressible alleles at these loci are unaffected as are known missense mutations at the ya and gdha loci. this is consistent with the premise that the suppressible mutations are nonsense and that this highly-allele-specific phenotypic suppression can be used to distinguish nonsense from missense mutations of aspergillus nidulans. paromomycin and tobramycin are rec ...19836340750
laccase localized in hulle cells and cleistothecial primordia of aspergillus nidulans.several species of the genus aspergillus form sexual spores within minute (approximately 0.2 mm) spherical shells (cleisthothecia) which are woven from specialized hyphae. aspergillus nidulans cleistothecia are uniquely characterized by their dark red coloration and an envelope of thick-walled globose cells (hulle cells). by use of a new chromogenic substrate, we have shown that the constitutent hyphae of young cleistothecia and the hulle cells which surround the cleistothecia of a. nidulans exh ...19836341366
conditionally lethal tubulin mutations of aspergillus nidulans.conditionally lethal tubulin mutants are becoming an important tool for studying microtubule structure and function. in the filamentous fungus aspergillus nidulans it has been possible to isolate heat-sensitive beta-tubulin mutations by isolating mutants resistant to the anti-microtubule agent benomyl and screening these mutants for heat sensitivity. it has also been possible to isolate alpha-tubulin mutations, new beta-tubulin mutations and mutations in other genes whose products are likely to ...19836341617
short-cycle conidiation in aspergillus nidulans influence of glucose concentration and acetate or citrate supply.this paper considers the effects of the reduction of the glucose concentration in the medium or of its substitution by intermediates closely related to the tca cycle, namely acetate and citrate, on the balance between conidiation and mycelial growth in aspergillus nidulans. it is shown that in conditions of extreme depletion of glucose in the medium, or in the presence of citrate as the only source of organic carbon, the reduction of mycelial growth proceeds to such as extent that conidiophores ...19836341779
the sub-cellular localisation of pyruvate carboxylase and of some other enzymes in aspergillus nidulans.the sub-cellular localisation of enzymes has been defined by latency analysis, and fractionation by differential centrifugation, in cell-free extracts prepared from the mycelium of aspergillus nidulans by growth in the presence of 2-deoxyglucose followed by treatment with a mixture of beta-glucuronidase, sulphatase and beta-glucanase and exposure to n2 cavitation at 5.2 pma. in such extracts pyruvate carboxylase and nad-dependent and nadp-dependent glutamate dehydrogenases are exclusively locali ...19836345155
nitrite toxicity in aspergillus nidulans: a new locus in a proa1 pabaa6 ya2 strain. 19836345269
mutagenicity screening with fungal systems.several fungal species have been used for mutagenicity screening: aspergillus nidulans, saccharomyces cerevisiae, and neurospora crassa. the eukaryotic nature of these organisms with typical chromosomes in a nucleus and their mitotic and meiotic mode of nuclear division have been the basis for the development of test systems that cover the full spectrum of genetic changes typical for eukaryotes. it is possible to detect simple point mutations and also grosser structural chromosomal alterations. ...19836349475
properties of deoxyribonuclease 4 from aspergillus nidulans.deoxyribonuclease 4 from aspergillus nidulans was purified to over 70% homogeneity. it contains a polypeptide of mr about 30000, and behaves as a dimer, but with some evidence of dissociation on gel filtration and ultracentrifugation. the ph optimum is 7-9. activity is supported by metal ions in the order (mn2+ + ca2+) greater than mn2+ approximately equal to (mg2+ + ca2+) much greater than mg2+. mn2+ is optimal at 10-20 mm. dnaase 4 strongly prefers native dna, for which the km is about 0.5 mm, ...19836349692
nitrate uptake in aspergillus nidulans and involvement of the third gene of the nitrate assimilation gene aspergillus nidulans, chlorate strongly inhibited net nitrate uptake, a process separate and distinct from, but dependent upon, the nitrate reductase reaction. uptake was inhibited by uncouplers, indicating that a proton gradient across the plasma membrane is required. cyanide, azide, and n-ethylmaleimide were also potent inhibitors of uptake, but these compounds also inhibited nitrate reductase. the net uptake kinetics were problematic, presumably due to the presence of more than one uptake ...19836350263
mitochondrial transfer rna genes from fungi (aspergillus nidulans) and plants (lupinus luteus) are transcribed in xenopus laevis oocyte nuclei.three plasmids containing aspergillus nidulans mitochondrial transfer rna genes were microinjected into the nucleus of xenopus laevis oocytes. plasmids that contained a single trnacys gene or two trna genes (arg and asn) yielded trna-sized transcripts. plasmids containing cloned lupinus mitochondrial trna genes were also transcribed and processed in x. laevis nuclei.19836350603
kinetics of the nuclear division cycle of aspergillus nidulans.we have analyzed the cell cycle kinetics of aspergillus nidulans by using the dna synthesis inhibitor hydroxyurea (hu) and a temperature-sensitive cell cycle mutant nimt that blocks in g2. hu rapidly inhibits dna synthesis (s), and as a consequence progression beyond s to mitosis (m) is blocked. upon removal of hu the inhibition is rapidly reversible. conidia (asexual spores) of nimt were germinated at restrictive temperature to synchronize germlings in g2 and then downshifted to permissive temp ...19836352675
isolation of genomic clones containing the amds gene of aspergillus nidulans and their use in the analysis of structural and regulatory mutations.previous analysis of the amds gene of aspergillus nidulans has identified multiple regulatory circuits mediated by trans-acting regulatory genes, cis-acting mutations have been identified and shown to specifically affect individual regulatory circuits. fine-structure genetic mapping of the amds regions showed that these cis-acting mutations occur in a complex controlling region adjacent to the amds structural gene. the amds gene was cloned by differential hybridization, using cdna probes derived ...19836353203
purification and properties of two neutral proteinases from aspergillus nidulans.two proteinases have been purified from mycelial extracts of aspergillus nidulans. both enzymes have ph optima between 6.5 and 7.5 and are inhibited by phenylmethane sulphonyl fluoride and by di-isopropyl fluorophosphate. the molecular weights and isoelectric points of proteinase i and proteinase ii are 30 900 and 30 000, and 4.6 and 4.3, respectively. both enzymes have a similar range of substrate specificities. the principal differences in their properties are that proteinase i is sensitive to ...19836355383
a polyamine-sensitive mutant of aspergillus nidulans.a mutation designated spsa1 has been induced in the putrescine (pua2) auxotroph of aspergillus nidulans which enables this mutant to grow on low concentrations of spermidine in place of putrescine. in addition, the spsa1 mutant, irrespective of putrescine requirement, is abnormally sensitive to high concentrations of spermidine, spermine or the polyamine analogue methylglyoxal bis(guanylhydrazone). when spsa1 strains are grown on medium containing spermidine, uptake of the polyamine continues at ...19836355384
genotoxic activity of plant growth-regulating hormones in aspergillus nidulans.three plant growth-regulating hormones, indole-3-acetic acid (iaa), indole-3-butyric acid (iba), and kinetin (6-furfuryl-aminopurine), were tested for their genetic activity in aspergillus nidulans in a plate test. the first two hormones were found to greatly increase somatic segregation in the fungus whereas kinetin was not effective. several concentrations of the plant hormones were used and it was found that increasing concentrations of iaa and iba increased mitotic segregation of the fungus ...19836357521
the genetic location of three mutations impairing penicillin production in aspergillus nidulans.three mutations impairing penicillin production in aspergillus nidulans, npeb, npec and nped, have been located on linkage groups iii, iv and ii, respectively, and positioned relative to other loci on these chromosomes.19836361214
the intron of the mitochondrial 21s rrna gene: distribution in different yeast species and sequence comparison between kluyveromyces thermotolerans and saccharomyces cerevisiae.we have screened numerous different yeast species for the presence of sequences homologous to the intron of the mitochondrial 21s rrna gene of saccharomyces cerevisiae (intron r1) and found them in all kluyveromyces species, some of the saccharomyces species and none of the other yeasts tested. we have determined the nucleotide sequence of the r1-intron in k. thermotolerans and compared it with that of s. cerevisiae. the two introns are inserted at the same position within the 21s rrna gene. the ...19836361491
cloning and characterization of the ornithine carbamoyltransferase gene from aspergillus aspergillus nidulans dna fragment composed of two adjacent sali subfragments (1.8 and 0.85 kb) that carries an argb gene complementing the yeast arg3 mutation has been isolated from two different gene libraries. hybridization results and immunological tests indicate that the cloned fragment contains the a. nidulans structural gene coding for ornithine carbamoyltransferase (otcase). using the cloned gene as a probe, the specific mrna was identified. the level of this rna observed in a. nidulan ...19836363209
aspects of genetic interaction in hybrids of aspergillus nidulans and aspergillus rugulosus obtained by protoplast fusion.hybrids were produced by protoplast fusion between strains of aspergillus rugulosus and mitotic master strains of aspergillus nidulans with a genetic marker on each linkage group. analysis of segregants induced by growth on benomyl revealed recombination between every pair of unlinked markers. parental combinations of markers were often recovered at significantly higher frequencies than expected. this aberrant segregation was not correlated with any particular pair of linkage-groups and was attr ...19836363618
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