TitleAbstractYear(sorted ascending)
a review of the coordinated research effort on the comparison of test systems for the detection of mutagenic effects, sponsored by the e.e.c.under the environmental research programme of the commission of the european communities a coordinated comparative test programme was started to assess the mutagenic effects of chemicals in as many different assay systems as possible. a preliminary report is given on the results for 5 compounds selected by the contact group "genetic effects of chemicals". 11 laboratories contributed data from tests in their expertise. the compounds were methyl methanesulfonate (mms), n-nitrosodiethylamine (den), ...19806769035
a possible rôle for acid phosphatase in gamma-amino-n-butyrate uptake in aspergillus nidulans.previously published work from another laboratory has shown that the mutation pacc-5 in the ascomycete aspergillus nidulans leads to loss of an acid phosphatase (ec activity and is probably located in the structural gene for this enzyme. here, we show that, pleiotropically, pacc-5 considerably reduces gamma-amino-n-butyrate transport levels as shown both by direct uptake measurements and two kinds of growth tests. a reduction in expression of the permease specified by the gaba gene is a ...19806992731
international commission for protection against environmental mutagens and carcinogens. icpemc publication no. 5: an evaluation of the genetic toxicity of dichlorvos. 19806782471
mutagenicity of halogenated aliphatic hydrocarbons in salmonella typhimurium, streptomyces coelicolor and aspergillus nidulans.eight structurally related halogenated aliphatic hydrocarbons mono-, di- and trichloroacetaldehyde (the last in the anhydrous and hydrate form), moni-, di- and trichloroethanol and allyl chloride, were tested for their ability to induce gene mutations in prokaryotic and eukaryotic microorganisms. the genetic systems employed were the salmonella reversion test with strain ta1535 and ta100, with and without metabolic activation, a forward and a back-mutation system in s. coelicolor and two forward ...19806991142
co-synthesis of penicillin following treatment of mutants of aspergillus nidulans impaired in antibiotic production with lytic enzymes.mycelia from four mutants of aspergillus nidulans impaired in penicillin production at separate genetic loci were treated with an enzyme complex capable of lysine cell walls, then mixed in all possible paired combinations and grown in osmotically buffered penicillin production media, containing 2-deoxyglucose and an unrefined mixture of polyoxins to prevent cell wall regeneration. the culture filtrates were assayed after 6 d and significant penicillin yields were observed in four of the six poss ...19806785377
nuclear movement is beta--tubulin-dependent in aspergillus nidulans. 19806986988
[antimitotic activity of methylbenzimidazol-2-yl-carbamate (mbc). i. light, electron microscopic and physiological studies of germinating conidia of aspergillus nidulans].in the presence of methylbenzimidazol-2-yl carbamate (mbc) swelling of conidia of aspergillus nidulans was not influenced. the total dna content per nucleus doubled only once, indicating that the first cell cycle was arrested in the g2-period. later rna as well as protein synthesis were inhibited. nuclear migration into the germ tube and tip growth were delayed. mbc-treatment induced nuclear enlargement and inhibited the first nuclear division in the germinating conidia. a characteristic nuclear ...19806990640
[structure of nucleosome (author's transl)]. 19806994083
nickel requirement of a urease-deficient mutant in aspergillus nidulans.the addition of nickel ions restored urease activity in vivo and ability to grow on urea in a mutant strain of aspergillus nidulans otherwise unable to utilize urea. this train carries a mutation in the ured locus, one of four loci involved in urea utilization. no other urease-deficient strains tested responded to the presence of nickel ions. the analogous characteristics of the ured mutant and the nitrate reductase and xanthine dehydrogenase associated cnxe mutants in aspergillus nidulans are d ...19806988544
bacteriophage infection interferes with guanosine 3'-diphosphate-5'-diphosphate accumulation induced by energy and nitrogen starvation in the cyanobacterium anacystis nidulans.anacystis nidulans accumulates large amounts of guanosine 3'-diphosphate-5'-diphosphate (ppgpp) upon nutritional or energy starvation induced by light-to-dark shift, treatment with carbonylcyanide-m-chlorophenylhydrazone (an uncoupler), or treatment with l-methionine-dl-sulfoximine (an inducer of nitrogen starvation). in contrast to healthy a. nidulans cells, those infected by as-1 cyanophage do not respond with ppgpp accumulation when starved after about one-third of the complete infection cyc ...19806777368
developmental gene regulation in aspergillus nidulans. 19806997115
developmental regulation of laccase levels in aspergillus nidulans.asexual spores (conidia) of aspergillus nidulans contain a dark green pigment which is not present in other cell types. synthesis of this pigment is catalyzed, in part, by a developmentally controlled p-diphenol oxidase, or laccase, encoded at the gamma a genetic locus (a. j. clutterbuck, j. gen. microbiol. 70:423-435, 1972). we have investigated the mechanisms regulating expression of the gamma a gene of a. nidulans. vegetative hyphae grown in submerged culture lacked detectable laccase enzyme ...19807000747
membrane-damaging agents cause mitotic non-disjunction in aspergillus nidulans. 19807001225
response of aspergillus nidulans and physarum polycephalum to microwave irradiation.the influence of microwaves on genetic processes in aspergillus nidulans and physarum polycephalum was investigated. suspensions of organisms were exposed in the far zone to 2450-mhz waves at 10 mw/cm2 for one hour in both cw and pulsed (1 microsecond, 600 pps) fields. spores of a. nidulans were irradiated before and during germination. no changes in survival rate or in frequency of morphological mutation were found. polycephalum under the influence of cw microwaves incorporated 3h-thymine into ...19807003154
genetic analysis of resistant mutants to antimitotic benzimidazole compounds in schizosaccharomyces pombe.mutants resistant to the antimitotic compounds thiabendazole and methyl-2-benzimidazole-carbamate were isolated and analyzed genetically in the fission yeast. schizosaccharomyces pombe. they comprised three groups in terms of genetic linkage. mutants in one linkage group (ben1) differed phenotypically from those in the other two (ben2 and ben3). the former were resistant to the compounds at any physiological temperature tested, whereas the latter exhibited temperature dependent resistance. throu ...19807003311
high sensitivity of deoxyribonuclease 4 of aspergillus nidulans to inhibition by orthophosphate. 19807004941
neutral proteinases in germinating conidia and hyphae of aspergillus nidulans. 19807004944
[mutagenic effect of combined exposure to 8-methoxypsoralen or angelicin and long-wave ultraviolet light in uvs-strains of aspergillus nidulans].combined mutagenic effect of near ultraviolet irradiation (nuv, lambda > 320 nm) and angelicin, which forms monoadducts, or 8-methoxypsoralen (8-mop), which forms monoadducts and cross-links in dna, were studied in uvs and uvs+ strains of aspergillus nidulans. mutations were induced intensively by both kinds of furocumarins. the induction of mutations by angelicin testifies the significance of psoralen-pyrimidine monoadducts in mutagenesis. using the method of fractionating nuv-irradiation and s ...19807005024
[x-ray-induced dna degradation in aspergillus nidulans cells. comparative analysis of uv- and xray-induced dna degradation].x-ray irradiation of aspergillus nidulans wild strain cells from logarithmic phase of growth lead to delay of dna synthesis. insignificant enzymatic dna degradation accomplished with its repair takes place. there is no direct dependence between doses of irradiation and levels of dna degradation. investigation of x-ray induced dna degradation in the number of uvs-mutants has demonstrated the existence of two branches of dna degradation: dependent and independent on external source of energy. depe ...19807005025
sorbitol dehydrogenase activity in some galactose non-utilizing mutants of aspergillus nidulans. 19807007224
genetic evidence for a second asparaginase in aspergillus nidulans.the apna1 mutation strongly reduces l-asparagine utilization in aspergillus nidulans. the ahra1 mutation, leading to loss of an l-asparaginase (drainas et al., 1977), eliminates residual l-asparagine utilization in double mutant strains also carrying apna1. this additivity suggests that a. nidulans, like saccharomyces cerevisiae (jones, 1977; dunlop et al., 1978), has two l-asparaginases specified by apna and ahr a, respectively, apna has been mapped to a position on the left arm of linkage grou ...19807019388
genetics of penicillin titre in lines of aspergillus nidulans selected through recurrent mutagenesis.genetic analyses of mutations for increased penicillin titre were carried out on two strains of aspergillus nidulans isolated after independent programmes of recurrent mutation and selection, similar to those used industrially for strain improvement. both selected strains were stable in terms of colony morphology and penicillins titre. backcrosses to the unselected ancestor indicated that the increased yield of each strain was due to an induced polygenic system with both additive and non-additiv ...19807019390
genetic regulation of isocitrate lyase activity in aspergillus nidulans. 19807012277
mutagenicity of pesticides evaluated by means of gene-conversion in saccharomyces cerevisiae and in aspergillus nidulans.nine pesticides, afugan, atrazine, benomyl, captan, daconil, melthaumittel, plantvax, saprol, and wepsin were tested for the induction of mitotic gene-conversion in two different eucaryotic microorganisms, saccharomyces cerevisae and aspergillus nidulans. in s cerevisiae the pesticides were also tested after mouse liver microsomal activation; in a nidulans all tests were performed using both resting and germinating conidia. among the tested pesticides, only captan revealed a consistent genetic a ...19807032901
aspergillus nidulans and aspergillus fumigatus as causal agents of bovine mastitis.five cases of bovine udder aspergillosis diagnosed clinically and confirmed by repeated demonstration of fungal hyphae in koh preparations and isolation of the organism from milk sediments are described. in one case the fungus was identified as aspergillus nidulans, in the other 4 cases as a. fumigatus. the most pronounced features in altered udders were multiple abscesses with distinctive colonies of fungal hyphae in the centres, embedded in cell detritus, neutrophils and macrophages. these pur ...19806988991
[comparative study of the oxygen reduction in photosystem ii of the cyanobacteria, anacystis nidulans and anabaena variabilis].oxygen reduction in the photosystem ii (ps ii) of thylakoid membranes from the cyanobacteria anacystis nidulans and anabaena variabilis was studied in the system simo + dcmu in whose presence competitive electron transport to simo and o2 in possible. the reagents of the mehler reaction were used; these reagents activate oxygen uptake by interacting with the reduced forms of oxygen (malonate and oxalate with o2; glyoxylate and catalase + ethanol with h2o2). the use of the reagents as shown that t ...19806782430
a third gene affecting gaba transaminase levels in aspergillus nidulans. 19807007164
light harvesting in anacystis nidulans studied in pigment mutants.spontaneous pigment mutants of anacystis nidulans were self-selected for improved growth in far red light (> 650 nanometers). questions were asked about those features of the light-harvesting mechanism which altered to give the mutants improved photosynthetic performance in far red. answers were sought by comparing pigment and reaction center concentrations for the parent and six mutants grown in gold fluorescent and in far red light. three significant results emerged. the ratio of reaction cent ...198016661593
cloning of aspergillus nidulans dna. i. selection and analysis of recombinant plasmids capable of complementing pyrf, argif and proab mutations in escherichia coli.fragments of aspergillus nidulans dna obtained after digestion with ecori, bamhi and hindiii endonucleases were cloned in escherichia coli in plasmid pbr322. these gene banks were used for transformation of 15 e. coli auxotrophic mutants and in 5 cases prototrophic clones containing recombinant plasmids were selected. three different recombinant plasmids conferring prototrophy to pyrf, proab and argif mutants were analyzed. hybridization experiments indicated that in two of these plasmids the in ...198019852107
cloning and analysis of recombinant plasmids containing genes for aspergillus nidulans 5 s rrna.genes coding for 5s rrna were found to be dispersed in the aspergillus nidulans genome. three different recombinant plasmids hybridizing to 5s rrna were isolated and their restriction enzyme maps were established.198124185988
mutations to constitutivity and derepression are separate and separable in a regulatory gene of aspergillus nidulans.previous work has shown that expression of the structural genes for the enzymes of nitrate and nitrite assimilation in aspergillus nidulans requires the products of two positively acting regulatory genes - nira, mediating induction, and area, mediating nitrogen metabolite repression. here we show that, in addition to previously described mutations in nira leading to constitutivity, other mutations can be selected in nira leading to nitrogen metabolite derepression. these constitutivity and depre ...198124185869
high frequency transfer of species specific mitochondrial dna sequences between members of the aspergillaceae.the mitochondrial genome of aspergillus nidulans var. echinulatus is approximately 20% larger than that of the closely related species aspergillus nidulans (eidam) winter. restriction enzyme mapping and electron microscopy has revealed that the size difference is due to the presence of six inserted sequences in the former. with the exception of a small number of species specific restriction sites and the six insertions/deletions, the two mitochondrial genomes appear identical. protoplast fusion ...198124190134
gene roles in the prn cluster of aspergillus nidulans.the roles of the four genes of the prn gene cluster involved in l-proline catabolism in aspergillus nidulans have been investigated. prnd and prnc encode, respectively, proline exidase and δ(i)-pyrroline-5-carboxylate (p5c) dehydrogenase. prnb is almost certainly the structural gene for the proline-inducible major proline permease. the prna product has no structural role in these activities but is a positive acting regulatory molecule necessary for the expression of prnd, prnc and, to a lesser e ...198124189952
chilling susceptibility of the blue-green alga anacystis nidulans: ii. stimulation of the passive permeability of cytoplasmic membrane at chilling temperatures.potassium ions and amino acids were found to leak from the cytoplasm to the outer medium when the blue-green alga, anacystis nidulans, was exposed to the chilling temperatures. the leakage was marked below the critical temperature regions, the midpoint values for which were around 5 and 14 c in cells grown at 28 and 38 c, respectively. these temperature regions coincided with those critical for the susceptibility of the photosynthetic activities and the carotenoid absorption spectrum previously ...198116661623
a method for the selection of deletion mutations in the l-proline catabolism gene cluster of aspergillus nidulans. 19817035292
induced gene mutation and mitotic non-disjunction in a. nidulans.toxicants of different classes were analysed for capacity to induce gene mutation and mitotic non-disjunction in aspergillus nidulans, using selective and permissive tests, respectively. ethanol, amphotericin b and micanozole, all affecting membrane integrity, induced only non-disjunction, emphasizing the röle of the membrane in mitosis. benomyl and isopropyl-3-chlorophenyl carbamate (cipc), two pesticides which interfere with spindle system, induced only non-disjunction. conversely, mitomycin c ...19817036415
growth characteristics of saccharomyces cerevisiae and aspergillus nidulans when biotin is replaced by aspartic and fatty acids.when either aerobic or anaerobic cultures of saccharomyces cerevisiae were supplemented with aspartic and fatty acids in place of biotin, stationary phase populations were very small compared with those obtained in the presence of biotin. similarly, these acids failed to fulfil the role of biotin-requiring strain of aspergillus nidulans. furthermore, a requirement for saturated fatty acid was found with anaerobically cultured s. cerevisiae. cells were fragmented when biotin was replaced by aspar ...19817033444
induction of point mutations by benomyl in dna-repair-deficient aspergillus nidulans. 19817019695
the microbiology of spent mushroom compost and its dust.microorganisms in spent steamed mushroom compost and its dust were enumerated, and identified. some phase ii (indoor composting) compost samples were also examined. steaming of spent compost resulted in a 70-76% reduction in microbial numbers. total counts made with compost fusion agar were approximately two logs greater than those for nutrient agar. the most common bacterial isolate was bacillus licheniformis. the most common actinomycete isolates were streptomyces diastaticus and thermoactinom ...19817197578
the regulation of phosphoenolpyruvate carboxykinase and the nadp-linked malic enzyme in aspergillus has previously been suggested that the synthesis of phosphoenolpyruvate carboxykinase (ec in aspergillus nidulans is regulated by a repression-derepression mechanism involving a glycolytic intermediate, and not by induction. results obtained using compounds that enter the tricarboxylic acid cycle via 2-oxoglutarate, and that can supply both a carbon and a nitrogen source for a. nidulans, suggest it is more likely that the synthesis of phosphoenolpyruvate carboxykinase is inducible, ...19817033461
mitotic processes which restore genome balance in aspergillus nidulans.previous work had shown that haploid strains of aspergillus nidulans with a duplicate chromosome segment (one in normal position, one translocated to another chromosome) were unstable at mitosis; genome balance was restored by spontaneous deletion of either duplicate segment. diploids with an extra, translocated segment showed high instability which was confined to the excess segments; loss of one of these, usually that in translocated position, gave balanced diploid nuclei and the loss was assu ...19817033469
organization of a gene cluster expressed specifically in the asexual spores of a. nidulans.we have investigated the organization and regulation of a 13.3 kb region of the aspergillus nidulans genome that is preferentially expressed during conidiophore development. this cloned dna segment codes for six polysomal poly(a)rnas present in dormant asexual spores (conidia) at from 8 to 50 copies per cell. the genes encoding these rnas occur once per haploid genome, are separate and distinct, appear to be colinear with their mature rna products and are present in both polarities. two of the g ...19817034956
splice points of the third intron in the yeast mitochondrial cytochrome b gene.we report the nucleotide sequences at the splicing junctions of intron 13 of the cytochrome b (box) "long" gene of the mitochondrion of saccharomyces cerevisiae and compare them with the homologous sequences in aspergillus nidulans. the two introns occupy exactly the same position and display an open reading frame in phase with the preceding exon at the 5' end and a blocked region at the 3' end.19817034963
the mosaic organization of the apocytochrome b gene of aspergillus nidulans revealed by dna sequencing.the coding section of the apocytochrome b gene (coba) of the mitochondrial dna of aspergillus nidulans has been completely sequenced. the gene comprises two exons of 507 and 654 bp separated by one intron of approximately 1.1 kb. the derived amino acid sequence shows 61% homology with that of saccharomyces cerevisiae and 51% homology with the cognate human sequence. comparison of these sequences indicates that uga codes for tryptophan in the a. nidulans mitochondrial system. the intron is in exa ...19817034966
induction of fenarimol-efflux activity in aspergillus nidulans by fungicides inhibiting sterol biosynthesis.fungicides inhibiting sterol biosynthesis belong to chemically distinct classes such as imidazole, morpholine, pyridine, pyrimidine and triazole derivatives. incubation of mycelium of aspergillus nidulans for 90 min with representatives of these fungicides induced an efflux activity which prevented accumulation of fenarimol, a pyrimidine derivative, into the mycelium. induction of this efflux activity reduced the fungitoxicity of fenarimol. addition of oligomycin to mycelium in which fenarimol-e ...19817040601
positive regulation in a eukaryote, a study of the uay gene of aspergillus nidulans. ii. identification of the effector binding this publication we report the identification of a protein likely to be coded by uay, a regulatory gene in the ascomycete aspergillus nidulans. uay is a positive control gene necessary for the expression of at least eight unlinked structural genes involved in purine uptake and degradation (scazzocchio and gorton 1977). the physiological effector of the uay system is uric acid, while some of its thioanalogs serve as gratuitous inducers. effector binding proteins were detected by binding to 2-t ...19817012545
isolation of protoplasts from aspergillus nidulans conidiospores.protoplasts were prepared from conidiospores of aspergillus nidulans. the mononucleated conidia gave protoplasts of a uniform size, approximately 5-micron diameter, depending on the strain and the stabilizing medium used. conidia were preincubated with 2-deoxy-d-glucose in a minimal medium at 37 degrees c for 3 h. the swollen conidia were collected, resuspended in a buffer containing 0.4 m (nh4)2so4 as stabilizer, and incubated with oerskovia lytic enzymes at 30 degrees c for 3 or 4 h. approxima ...19817016284
a beta-tubulin mutation in aspergillus nidulans that blocks microtubule function without blocking assembly.we have isolated a heat-sensitive beta-tubulin mutation, bena33, that blocks nuclear division and nuclear movement at restrictive temperature. this blockage demonstrates that the beta tubulin encoded by the bena gene is essential to both processes. the blockage of both processes is suppressed by the alpha-tubulin mutation, tuba1; thus the alpha tubulin encoded by the tuba gene must also be involved in both processes. when bena33 is shifted from a permissive to restrictive temperature, nuclei are ...19817018696
lipid components variation among the temperature-sensitive mutants and wild strain of aspergillus nidulans.the fungus aspergillus nidulans and its two temperature-sensitive mutants were grown in synthetic media at permissive and restrictive temperatures. after seven days of growth, total lipids were extracted and characterised from the mycelia. in the case of the wild strain, an increase in the incubation temperature resulted in an increase in the ratio of unsaturated to saturated fatty acids and was inversely proportional to the ratio of short chain to long chain fatty acids. it was interesting to n ...19817021468
induction of extracellular proteases by egg-white in aspergillus nidulans.aspergillus nidulans when supplemented with egg-white protein (1 %) produced considerable amounts of proteases extracellularly. the order of the appearance of the proteolytic enzymes growth on untreated and heat-inactivated egg-white were studied. they showed ph optima of 5, 7.2 and 9 when assayed at 37 degrees c. it is proposed that one of the factors leading to higher cell mass of a. nidulans in the presence of egg-white is the availability of protease-catalyzed hydrolyzed products of egg-whit ...19817021371
pyruvate carboxylase from aspergillus nidulans. regulatory properties. 19817026241
mutagenicity of monoadducts and cross-links induced in aspergillus nidulans by 8-methoxypsoralen plus 365 nm radiation. 19817027284
a third unlinked gene controlling the pyruvate dehydrogenase complex in aspergillus nidulans.pyruvate dehydrogenase complex mutants of aspergillus nidulans were obtained by ultraviolet treatment and enrichment procedures. among 160 glycolytic mutants, 86 pyruvate dehydrogenase complex mutants (including some temperature-sensitive mutants) were found. in addition to genes pdha and pdhb, which are described in previous studies, a third gene, pdhc, controlling the function of the enzyme complex, was identified. the three genes were not linked and were mapped in the following linkage groups ...19817028719
dominant spore color mutants of aspergillus nidulans defective in germination and sexual development.the ascomycete aspergillus nidulans produces green conidia (asexual spores). recessive mutants which produce yellow conidia have been previously isolated from haploid strains and have been shown to be deficient in laccase (diphenol oxidase), an enzyme that requires copper for activity. using a diploid parent strain, we isolated dominant yellow conidial mutants which, in the haploid state, produced even less laccase activity than a recessive mutant. three isolates of such mutants behaved similarl ...19817028722
rna synthesis during the germination of conidia of aspergillus nidulans.rna accumulates most rapidly in germinating conidia of aspergillus nidulans between 6 h and 14 h after the initiation of germination. 3h-adenine is incorporated into all classes of rna before the emergence of the germ tube, but most of the label appears in rrna. there is an increase in total rna polymerase activity, which occurs in parallel with the increase in rna synthesis. three peaks of rna polymerase activity were separated on phosphocellulose columns and their properties investigated.19817031437
sensitive detection of tritium in southern blot and plaque hybridizations. 19817032353
an alpha-amanitin-resistant dna-dependent rna polymerase ii from the fungus aspergillus alpha-amanitin-resistant dna-dependent rna polymerase ii has been purified from the lower eukaryote aspergillus nidulans to apparent homogeneity by extraction of the enzyme at low salt concentration, polymin p (polyethylene imine) fractionation, binding to ion-exchangers and density gradient centrifugation. by this procedure 0.4 mg of rna polymerase ii can be purified over 6,000-fold from 500 g (wet weight) of starting material with a yield of 25% and a specific activity of 550 units/mg. the ...19817021153
selection for increased penicillin titre following hybridization of divergent lines of aspergillus nidulans.sexual hybridization of two divergent lines of aspergillus nidulans, which had been selected for increased penicillin titre through successive cycles of mutagenesis, released considerable variation for this character. the recovery of segregants with titres equivalent to that of the unselected ancestor suggested that mutations in different genes had been selected in the two lines. however, complementary segregants with substantially improved titres were not found, indicating interactions, probabl ...19817040598
mutagenicity of chemicals of industry and agricultural relevance in salmonella, streptomyces and aspergillus. 19817026896
thiram-induced abnormal chromosome segregation in aspergillus nidulans. 19817027033
evolution of rrna and origin of mitochondria. 19817027053
mitochondrial trna gene clusters in aspergillus nidulans: organization and nucleotide sequence. 19817008953
growth-mediated metabolic activation of promutagens in aspergillus nidulans.7 procarcinogens belonging to different chemical classes (nitrosamines, hydrazoalkanes, oxazaphosphorines and aromatic amines) were tested in a. nidulans for the induction of point mutations with two genetic systems (8-ag resistance and induction of methionine suppressors). dimethylnitrosamine, diethylnitrosamine, nitrosomorpholine, dimethylhydrazine, procarbazine and cyclophosphamide gave positive results with a good dose--effect relationship in the growth-mediated assay, whereas they gave nega ...19817010140
naturally occurring diploid isolates of aspergillus nidulans.six wild isolates belonging to heterokaryon compatibility group a of the birmingham aspergillus nidulans collection were shown to be diploid. five were proven heterozygous for a naturally occurring conditional lethal haploid genotype. it is considered unlikely that these diploids arose by mutation in storage. consequently, somatic diploidy is a regular occurrence in the natural population of this saprophytic species.19817033446
mutagenicity of methyl benzimidazole-2-yl carbamate (mbc) towards aspergillus nidulans (eidam) winter and cladosporium cucumerinum ellis & arth.the ability of methyl benzimidazol-2-yl carbamate (mbc) to induce point mutations to carboxin and mbc resistance was tested in aspergillus nidulans (eidam) winter and cladosporium cucumerinum ellis & arth. a sub-lethal concentration (e.d.50) of mbc, when incorporated into a complete agar medium, induced mbc resistance in germinating conidia of a. nidulans and carboxin resistance in germinating conidia of c. cucumerinum. the significance of these findings in relation to fungicide resistance in th ...19817010147
the ph dependence of the mutagenicity of methyl benzimidazol-2-yl carbamate (mbc) towards aspergillus nidulans (eidam) winter and cladosporium cucumerinum ellis & arth.the ability of methyl benzimidazol-2-yl carbamate (mbc) to induce point mutations to carboxin and mbc resistance in aspergillus nidulans (eidam) winter and cladosporium cucumerinum ellis & arth. was dependent upon the ph value of the agar medium into which it had been incorporated. the relevance of this in relation to testing chemicals for a possible mutagenic activity with microorganisms is discussed.19817010148
[otomycosis in the south of chile]. 19817034110
fatty acid composition of oil synthesized by aspergillus nidulans.the filamentous fungus aspergillus nidulans eidam strain 300 was found to be capable of synthesizing 24.9% oil or remarkably low free fatty acidity, in a chemically defined medium with 34% glucose as sole carbon source. although the total content of oil synthesized was less, utilization of the carbon source is better as shown by the high (8.4) fat coefficient. the major component fatty acids of the oil were palmitic, stearic, oleic and linoleic and are influenced by the source of carbon. palmito ...19817026394
cellular and extracellular siderophores of aspergillus nidulans and penicillium chrysogenum.aspergillus nidulans and penicillium chrysogenum produce specific cellular siderophores in addition to the well-known siderophores of the culture medium. since this was found previously in neurospora crassa, it is probably generally true for filamentous ascomycetes. the cellular siderophore of a. nidulans is ferricrocin; that of p. chrysogenum is ferrichrome. a. nidulans also contains triacetylfusigen, a siderophore without apparent biological activity. conidia of both species lose siderophores ...19816242827
anaplerotic metabolism of aspergillus nidulans and its effect on biomass synthesis in carbon limited chemostats.anaplerotic fixation of carbon dioxide by the fungus aspergillus nidulans when grown under carbon-limited conditions was mediated by pyruvate carboxylase and a phosphoenol pyruvate (pep)-metabolising enzyme which has been tentatively designated as pep carboxylase. the activities of both enzymes were growth rate dependent and measurements of h14co3 incorporation by growing mycelium indicated that they were responsible for almost all the assimilated carbon dioxide. in carbon-limited chemostats, th ...19816783000
picosecond energy transfer in porphyridium cruentum and anacystis nidulans.picosecond energy transfer is measured in anacystis nidulans and porphyridium cruentum. fluorescence is sensitized by a 6-ps laser flash, at 530 nm. the time dependence of fluorescence is measured with reference to the laser pulse. fluorescence is recorded from phycoerythrin (576 nm), r-phycocyanin (640 nm), allophycocyanin (666 nm), photosystem ii chlorophyll (690 nm) and long wave length chlorophyll (715 nm). energy transfer measurements are made at 37 degrees c, 23 degrees c, and 0 degrees c, ...19816788106
intergeneric cosynthesis of penicillin by strains of penicillium chrysogenum, p. chrysogenum/notatum and aspergillus nidulans.a number of mutants impaired in penicillin production have previously been isolated from penicillium chrysogenum and aspergillus nidulans. during cofermentation of osmotically fragile mycelia derived from these strains, in the presence of inhibitors of cell wall regeneration, intergeneric cosynthesis has been demonstrated between mutants which are probably impaired in different parts of th penicillin biosynthetic pathway.19816798163
regulation of nitrate reductase levels in the cyanobacteria anacystis nidulans, anabaena sp. strain 7119, and nostoc sp. strain 6719.the effect of the nitrogen source on the cellular activity of ferredoxin-nitrate reductase in different cyanobacteria was examined. in the unicellular species anacystis nidulans, nitrate reductase was repressed in the presence of ammonium but de novo enzyme synthesis took place in media containing either nitrate or not nitrogen source, indicating that nitrate was not required as an obligate inducer. nitrate reductase in a. nidulans was freed from ammonium repression by l-methionine-d,l-sulfoximi ...19816780511
solubility of (1 leads to 3)-beta-d/(1 leads to 6)-beta-d-glucan in fungal walls: importance of presumed linkage between glucan and saccharomyces cerevisiae, neurospora crassa, aspergillus nidulans and coprinus cinereus most of the alkali-insoluble (1 leads to 3)-beta-d/(1 leads to 6)-beta-d-glucan of the wall can be extracted with dimethyl sulphoxide. the same fraction, and in saccharomyces cerevisiae a small additional fraction, can be extracted by a destructive procedure involving 40% naoh at 100 degrees c. the small fraction of the glucan which resists this treatment becomes soluble after a subsequent treatment with h ...19816460846
nucleotide sequence of 5s ribosomal rna from aspergillus nidulans and neurospora crassa.the nucleotide sequences of 5s rrna molecules isolated from the cytosol and the mitochondria of the ascomycetes a. nidulans and n. crassa were determined by partial chemical cleavage of 3'-terminally labelled rna. the sequence identity of the cytosolic and mitochondrial rna preparations confirms the absence of mitochondrion-specific 5s rrna in these fungi. the sequences of the two organisms differ in 35 positions, and each sequence differs from yeast 5s rrna in 44 positions. both molecules conta ...19816453331
microbial short-term assays with thiram in vitro.the fungicide thiram was assayed in the following tests in vitro, with and without metabolic activation: (1) prophage lambda induction of escherichia coli k12; (2) repair test in salmonella typhimurium (strains ta1538 and ta1978); (3) induction of gene mutations in aspergillus nidulans (metha1 suppressor induction). thiram was positive in the repair test and in the a. nidulans forward-mutation test (4-6 fold increase) in the absence of metabolic activation. a slight increase was observed in prop ...19816454074
adenosine triphosphatase of aspergillus nidulans: variation of ca2+-atpase isoenzymes. 19816456218
atpase activity in gal mutants of aspergillus nidulans. 19816458561
biochemical analysis of mutants defective in nitrate assimilation in neurospora crassa: evidence for autogenous control by nitrate reductase.a biochemical analysis of mutants altered for nitrate assimilation in neurospora crassa is described. mutant alleles at each of the nine nit (nitrate-nonutilizing) loci were assayed for nitrite reductase activity, for three partial activities of nitrate reductase, and for nitrite reductase activity. in each case, the enzyme deficiency was consistent with data obtained from growth tests and complementation tests in previous studies. the mutant strains at these nit loci were also examined for alte ...19816460156
the cloning of aspergillus nidulans mitochondrial dna in escherichia coli on plasmid pbr322. 19816270505
nucleotide sequence of the aspergillus nidulans mitochondrial gene coding for the small ribosomal subunit rna: homology to e. coli 16s rrna.the complete primary structure of the 1437 bp gene coding for mitochondrial 15s rrna and its flanking regions was determined by maxam-gilbert sequencing of cloned hindiii fragment h3 of a. nidulans mtdna. the gene product reveals significant homology (59%) to e. coli 16s rrna, and the potential secondary structures of both rrna molecules are very similar, except that the hairpin structures 7, 8 and 30 of the brimacombe 16s rrna model are deleted, and that two sequences of 8 and 31 nucleotides ar ...19816273804
vectors for cloning in cyanobacteria: construction and characterization of two recombinant plasmids capable of transformation of escherichia coli k12 and anacystis nidulans r2.two plasmids were constructed consisting of the e. coli vector pacyc184 and the cyanobacterial plasmid puc1. these recombinants, designated puc104 and puc105, can be transformed to e. coli k12 as well as to the cyanobacterium anacystis nidulans r2 and in both hosts they express their antibiotic markers. puc104 and puc105 differ with respect to the location and the orientation of the pacyc184 segment in puc1. puc104 was found to be stable under all circumstances. transformation of puc105 to a. ni ...19816276694
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
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
international commission for protection against environmental mutagens and carcinogens. committee 2 final report. mutagenesis testing as an approach to carcinogenesis. 19826214712
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
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
a new approach for molecular cloning in cyanobacteria: cloning of an anacystis nidulans met gene using a tn901-induced mutant.a new strategy for molecular cloning in the cyanobacterium anacystis nidulans r-2 is described. this strategy involved the use of a transposon and was developed for the cloning of a gene encoding methionine biosynthesis. a met::tn901 mutant was isolated. chromosomal dna fragments were cloned in the escherichia coli plasmid vector pacyc184. a recombinant plasmid carrying the inactivated met::tn901 gene was selected after transformation to e. coli. the cloned met::tn901 dna fragment was used as a ...19826298064
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
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
construction of a hybrid plasmid capable of replication in the bacterium escherichia coli and the cyanobacterium anacystis nidulans.a hybrid plasmid was constructed between the 5.3-megadalton plasmid (puh24) of anacystis nidulans r2 and the escherichia coli plasmid pbr322. this was accomplished by adding a transposon to pbr322 and transforming this dna into a. nidulans. one resultant hybrid, pls103, had a molecular weight of 6.8 x 10(6), replicated in both organisms, had unique sites for two restriction endonucleases, conferred ampicillin resistance on both organisms, and could be used as a cloning vector in a. nidulans.19826277870
restriction enzyme analysis of mitochondrial dna of members of the genus aspergillus as an aid in taxonomy.restriction endonuclease patterns of mitochondrial dna from seven species of the genus aspergillus (a. nidulans, a. wentii, a. awamori, a. niger, a. oryzae, a. tamarii and a. echinulatus) have been compared in order to test the phylogenetic relationships between these species. the fraction of restriction fragments common between all pairs of species from this set ranged from 0 to 1. the use of this approach for the taxonomy of the genus aspergillus is discussed. the postulated phylogenetic relat ...19826281364
organization of the ribosomal rna gene cluster in aspergillus nidulans.dna coding for ribosomal rna in aspergillus nidulans was found to consist of a unit 7.8 kb in size which is tandemly repeated in the genome and codes for 5.8s, 18s and 26s rrna. the repeat unit has been cloned, and its restriction map and the location of the individual rrna coding sequences within the unit have been established.19826282710
nucleotide sequence of a region of the mitochondrial genome of aspergillus nidulans including the gene for atpase subunit 6.a 1500 bp fragment of the aspergillus nidulans mitochondrial genome contains genes for arginine and asparagine trnas, an unassigned reading frame, and the structural gene for atpase subunit 6. the trna genes possess 66% nucleotide homology and possibly originated by a relatively recent duplication event. the unassigned reading frame displays a low level of homology with the human urf a6l. the predicted amino acid sequence of the a-nidulans atpase subunit 6 gene is 40% homologous to the yeast pol ...19826285306
cloning and expression in escherichia coli k-12 of the biosynthetic dehydroquinase function of the arom cluster gene from the eucaryote, aspergillus nidulans.a 1.35 md dna hindiii fragment containing part of the arom gene cluster or cluster gene of aspergillus nidulans encoding biosynthetic dehydroquinase (5-dehydroquinate hydrolyase) has been cloned in plasmid pbr322 on the basis of functional expression in escherichia coli. the fungal fragment on pbr322, designated phk29, complements a corresponding e. coli dehydroquinase structural gene (arod) mutation. phk29 contains one bamhi, hpaii, psti, smai, xhoi and surprisingly, one hindiii site since phk2 ...19826287167
nucleotide sequence of aspergillus nidulans mitochondrial genes coding for atpase subunit 6, cytochrome oxidase subunit 3, seven unidentified proteins, four trnas and l-rrna.the complete nucleotide sequence of a 14 kb segment of a. nidulans mtdna reveals a rather compact organization of genes transcribed from the same strand and coding for two functionally known proteins, seven unidentified polypeptides (urfs), 24 trnas and two rrnas. one of the urfs is located in the intron of the l-rrna gene and codes for a basic protein of 410 residues. the other urfs are in spacer regions and code for hydrophobic proteins. urfa is homologous to human urf4, and urfb produces a po ...19826290989
genetic approaches to the analysis of microbial development. 19826297378
a physical map of the ribosomal dna repeat unit of aspergillus nidulans.the ribosomal dna repeat unit of aspergillus nidulans has been cloned in pbr322 and a restriction map constructed. the genes coding for the 17s, 5.8s and 25s rrnas are found in blocks separated by a 1.7 kb spacer region, with the 5.8s rna gene lying between the genes for the two larger rnas. the total length of the repeat unit is 7.7 kb. the 5s rrna is not present in the repeat unit.19826299883
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