PMID(sorted descending)
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
genetic regulation of isocitrate lyase activity in aspergillus nidulans. 19807012277
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
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
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
mitochondrial trna gene clusters in aspergillus nidulans: organization and nucleotide sequence. 19817008953
sorbitol dehydrogenase activity in some galactose non-utilizing mutants of aspergillus nidulans. 19807007224
a third gene affecting gaba transaminase levels in aspergillus nidulans. 19807007164
[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
[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
neutral proteinases in germinating conidia and hyphae of aspergillus nidulans. 19807004944
high sensitivity of deoxyribonuclease 4 of aspergillus nidulans to inhibition by orthophosphate. 19807004941
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
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
membrane-damaging agents cause mitotic non-disjunction in aspergillus nidulans. 19807001225
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
developmental gene regulation in aspergillus nidulans. 19806997115
[structure of nucleosome (author's transl)]. 19806994083
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
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
[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
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
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
nuclear movement is beta--tubulin-dependent in aspergillus nidulans. 19806986988
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
de novo formation of the niad gene directed protomer in the nadph-nitrate reductase of aspergillus nidulans. 19826817753
urea and thiourea transport in aspergillus nidulans.wild-type aspergillus nidulans has an active transport system specific for urea which concentrates urea at least 50-fold relative to the extracellular concentration. it is substrate concentration dependent, with an apparent km of 3 x 10-(5) m for urea. competition studies and the properties of mutants indicate that thiourea is taken up by the same system as urea. thiourea is toxic at 5mm to wild-type cells of aspergillus nidulans. mutants, designated urea1 to urea16, resistant to thiourea have b ...19826814421
temperature-shift analysis of conidial development in aspergillus nidulans. 19826813166
the isolation of a fungal metabolite which exhibits antimicrobial synergy with sterigmatocystin. 19826802793
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
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
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
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
international commission for protection against environmental mutagens and carcinogens. icpemc publication no. 5: an evaluation of the genetic toxicity of dichlorvos. 19806782471
[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
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
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
air-borne fungi in the air of barcelona (spain). iii. the genus aspergillus link.during a survey on the presence of species of the genus aspergillus in the air of the city of barcelona (spain), the following species were identified: aspergillus flavus link, a. niger van tieghem, a. fumigatus fresenius, a. clavatus desmazières, a. terreus thom, a. chevalieri (mang.) thom et church, a. niveus bloch, emend. thom et church, a. ochraceus wilhelm, a. versicolor (vuillemin) tiraboschi, and a. amstelodami (mang.) church et thom.19806770271
a mutation, adjacent to gene amds, defining the site of action of positive-control gene amdr in aspergillus aspergillus nidulans the acetamidase enzyme is inducible by omega-amino acids, sources of acetyl-coenzyme a, and benzoate. the amdr (or inta) gene is a positive-control gene involved in omega-amino acid induction only. a cis-acting mutation amdi93 located in a complex controlling region adjacent to the acetamidase structural gene was found to abolish induction by omega-amino acids but not induction by other sources of induction. as predicted, this mutation was epistatic to constitutive amdr a ...19806769897
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
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
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
in vitro mutational studies with trifluralin and trifluorotoluene derivatives. 19826763485
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
meiosis in aspergillus nidulans: another example for lacking synaptonemal complexes in the absence of crossover interference. 19826761318
studies on air-borne fungi at qena. iii. thermophilic fungi. 19826759940
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
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
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
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
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
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
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
evaluation of 2 different genetic markers for the detection of frameshift and missense mutagens in a. nidulans.21 chemicals, known to induce missense and/or frameshift mutations directly, were assayed for their ability to forward mutate a haploid strain of a. nidulans. 2 genetic markers for forward mutations were used, namely 8-azaguanine resistance and induction of meth a1 suppressors. missense mutagens were usually active when tested with the plate-incorporation technique, whereas frameshift agents were ineffective; some of these, on the other hand, turned out to be positive when tested with a liquid-t ...19826750392
two-way selection of mutants and revertants to chloroneb resistance in aspergillus nidulans.5 mutants of aspergillus nidulans, selected for resistance to chloroneb, were also partially dependent on it. the resistance of these mutants to chloroneb was about 20-150 times higher than that of the original strain. the resistance marker was due to a mutation in a single gene, located in linkage group iii, and behaved as a recessive character. this genetic marker was distal in relation to galal with a recombination frequency of about 30-35%. the different levels of resistance were attributed ...19826750388
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
transhyphal electrical currents in fungi.representative mycelial fungi from the phycomycete, ascomycete and basidiomycete groups (achlya bisexualis, neurospora crassa, aspergillus nidulans, schizophyllum commune and coprinus cinereus) all generated steady electrical currents around their hyphal tips; the generation of a transhyphal ion current may therefore be a universal characteristic of hyphal growth. as with all other tip growing organisms, positive current always entered apically and left distally; non-growing hyphae did not drive ...19846520604
isolation of aneuploid-generating mutants of aspergillus nidulans, one of which is defective in interphase of the cell cycle.a method is described for isolating mutants potentially defective in loci involved in mitotic chromosome segregation. conditional lethal, heat-sensitive (42 degrees ) mutants were assayed at a subrestrictive temperature of 37 degrees for an inflated production of colonies displaying phenotypes and behavior patterns of whole chromosome aneuploids. of 14 mutants, three showed specificity for one disomic phenotype, whereas 11 generated colonies mosaic for different aneuploid phenotypes. this latter ...19846479583
nondisjunction induced in mouse spermatogenesis by chloral hydrate, a metabolite of trichloroethylene.the effects of chloral hydrate (ch), an in vivo metabolite of trichloroethylene, have been evaluated by cytogenetic observations of mouse secondary spermatocytes after ip treatment with 82.7, 165.4, or 413.5 mg/kg bw. hyper-haploid metaphases have been scored to determine whether previous observations in various nonmammalian organisms about an effect of this drug on the mitotic spindle could be confirmed in mice. at each dose, the frequencies of hyper-haploid cells have been estimated to assess ...19846479114
[in vitro comparative study of the sensitivity of aspergillus to antifungal agents].minimum inhibitory concentrations (mic) of amphotericin b, 5-fluorocytosine, miconazole, tioconazole, econazole and ketoconazole were determined for 310 aspergillus strains belonging to four different species isolated from clinical specimens. econazole exhibited the best in vitro activity with mic less than or equal to 3.12 micrograms/ml for 96% of strains and less than or equal to 1.56 micrograms/ml for 68%. for amphotericin b, 69% of strains were less than or equal to 1.56 micrograms/ml and, f ...19846462761
extracellular siderophores of rapidly growing aspergillus nidulans and penicillium chrysogenum.the highly active extracellular siderophores previously detected in young cultures of aspergillus nidulans and penicillium chrysogenum have been identified as the cyclic ester fusigen (fusarinine c), and its open-chain form, fusigen b (fusarinine b).19826461636
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
the genetic toxicology in fungi of 4-chloromethylbiphenyl (4cmb), 4-hydroxymethylbiphenyl (4hmb) and benzyl chloride (bc). survey of the results of the u.k.e.m.s. collaborative genotoxicity trial 1981. 19826460178
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
atpase activity in gal mutants of aspergillus nidulans. 19816458561
adenosine triphosphatase of aspergillus nidulans: variation of ca2+-atpase isoenzymes. 19816456218
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
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
mutagenesis assays with yeasts and moulds. 19806450173
[genetic control of pathways of pyrimidine metabolism in aspergillus nidulans. 1. isolation and genetic analysis of 6-azauracil resistant mutants].147 mutants exhibiting the resistance to toxic effect of 6 azauracil have been isolated by nitrosoguanidine treatment from the wild strain of aspergillus nidulans. this mutants have been divided into 11 phenotypic groups according to its cross-resistance to 5-fluoroderivatives of uracil, uridine and deoxyuridine. the genetic analysis has shown that all mutations of resistance are of nuclear origin and dominant nature, and they are distributed on six loci of the chromosome viii.19806450084
the isolation and characterization of mutants defective in nitrate assimilation in neurospora crassa.the isolation and characterization of mutants altered for nitrate assimilation in neurospora crassa is described. the mutants isolated can be subdivided into five classes on the basis of growth test that correspond to the growth patterns of existing mutants at six distinct loci. mutants with growth characteristics like those of nit-2, nit-3 and nit-6 are assigned to those loci on the basis of noncomplementation and lack of recombination. mutants that, from their growth patterns, appear to lack t ...19806449399
molecular cloning and selection of genes regulated in aspergillus development.over 350 clones homologous to poly(a)+ rnas that are significantly more prevalent in conidiating cultures of aspergillus nidulans than in somatic cells have been selected from a recombinant dna library formed between nuclear dna and lambda charon 4a. the procedure used for this selection involved in situ hybridization to a cdna probe which had been selectively depleted of sequences represented in somatic cells by complement hybridization. five of these clones have been characterized further. all ...19806449291
effect of growth substrates on phosphatases of aspergillus nidulans under heat stress. 19806447107
[fatty acid composition of the lipids in fungi of the genus aspergillus developing on mineral media with different carbon sources].this work was aimed at studying the effect of different carbon sources in the composition of mineral media on the growth of fungi belonging to the aspergillus genus and on the fatty acid composition of their lipids. a chemically-defined medium with glucose was shown to be optimal for the growth of 18 aspergillus strains and for the synthesis of lipids by them. the fatty acid composition of lipids was studied when the fungi grew in media with different carbon sources. the lipids were shown to con ...19846442390
regulation of the nitrate reductase level in anacystis nidulans: activity decay under nitrogen stress.the in vivo stability of ferredoxin-nitrate reductase from the cyanobacterium anacystis nidulans under conditions of inhibited protein synthesis has been studied in nitrate-grown cells. a light-promoted rapid decay in cellular nitrate reductase activity took place in the absence of any added nitrogen source, but not in the presence of nitrate, nitrite, or ammonium. the inactivation process seemed to proceed in two sequential steps. the first step required both light and oxygen, and was inhibited ...19846437330
vanadate and dicyclohexylcarbodiimide insensitive proton extrusion from oxygen pulsed cells of the cyanobacterium anacystis nidulans.oxygen pulses applied to dark anaerobic suspensions of anacystis nidulans provoked immediate acidification of the external medium. the reaction was inhibited only 75% by dicyclohexylcarbodiimide and 7-chloro-4-nitrobenz-2-oxa-1,3-diazole at concentrations which completely arrested all oxidative phosphorylation. carbonyl cyanide m-chlorophenylhydrazone eliminated the acidification of oxygen pulsed cell suspensions while ortho-vanadate and diethylstilbestrol had no effect. no lag occurred between ...19846433918
the nucleotide sequences of the 5 s rrnas of seven molds and a yeast and their use in studying ascomycete phylogeny.the sequences of the 5 s rrnas isolated from 8 ascomycete species belonging to the genera aspergillus, penicillium, acremonium and candida are reported. two of the examined strains each yielded a mixture of 3 slightly different 5 s rnas, which were individually sequenced after fractionation. a previously published sequence for aspergillus nidulans 5 s rna was found to contain errors. reconstruction of an evolutionary tree based on 5 s rna sequences showed that the 16 presently examined ascomycet ...19846429642
aspergillic acids produced by mixed cultures of aspergillus flavus and aspergillus nidulans.a mixed culture of aspergillus nidulans (gh79) and aspergillus flavus (cmi 91019b) produced two antibiotics, designated vi and vii, which were not elaborated when either fungus was grown alone. chemical and spectroscopic analysis of vi, the major component, indicated that this compound was identical to hydroxyaspergillic acid. the minor component, vii, was produced in too low a yield for its identity to be established. however, partial characterization suggests that this antibiotic also belongs ...19846427396
a convener role for the cnxh gene specified component in the nadph-nitrate reductase fron aspergillus nidulans.the role of the cnxh+ gene specified polypeptide in the formation and function of the nadph-nitrate reductase in aspergillus nidulans was examined with the use of two complementing mutant strains which were grown as forced heterocaryons in the presence of nitrate. the niad-421 structural gene mutant and the cnxh-318 co-factor gene mutant produce two components of the nadph-cytochrome c reductase co-activity which can be distinguished by their enzymatic and physical behavior. this combination ena ...19846423961
pyruvate carboxylase from aspergillus nidulans. effects of regulatory modifiers on the structure of the enzyme.a method is described for purification of pyruvate carboxylase from aspergillus nidulans by affinity chromatography on monomeric avidin-sepharose. the purified enzyme is homogeneous as judged by electrophoretic and immunochemical analysis. the sub-unit mr determined by electrophoresis in the presence of sodium dodecyl sulphate is 133000 +/- 5000. electron microscopic analysis of purified a. nidulans pyruvate carboxylase after negative staining with uranyl acetate reveals the presence of molecule ...19846421580
photoacoustic spectroscopy of anacystis nidulans. iii. detection of photosynthetic activities.photosynthetic activities of anacystis nidulans can be detected by photoacoustic spectroscopy. algae treated by a photosynthetic inhibitor are used to provide the signal from the photochemically inactive sample. the results of these measurements correspond well with the activities which can be monitored by conventional biochemical assays. acoustic data from a. nidulans are used to obtain the action spectrum for photochemical energy storage. it is concluded that phycocyanin harvests light for bot ...19846421239
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
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
mycologic identification of emericella nidulans and aspergillus flavus causing pulmonary infection. 19836413149
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
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
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 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
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
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
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
[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
regulation of pyrimidine salvage in aspergillus nidulans: a role for the major regulatory gene are a mediating nitrogen metabolite repression.the synthesis of thymine 7-hydroxylase, an alpha-ketoglutarate dependent dioxygenase, is subject both to nitrogen metabolite repression and to oxygen repression, while synthesis of the other pyrimidine salvage pathway dioxygenase, pyrimidine deoxyribonucleoside 2'-hydroxylase, is subject to neither. are a300, an allele of the positive acting regulatory gene are a mediating nitrogen metabolite repression in aspergillus nidulans, considerably elevates levels of thymine 7-hydroxylase, probably alle ...19846394961
structure and regulated expression of the spoc1 gene cluster from aspergillus nidulans.we have previously described the organization of a 13.3 kb region of the aspergillus nidulans genome, designated spoc1, coding for multiple poly(a)+ rnas that accumulate in asexual spores but not in somatic cells. we have determined the limits of the spoc1 gene cluster by investigating the transcriptional features of 53 kb of chromosomal dna. this segment of the genome codes for at least 19 poly(a)+ rnas, some of which are transcribed from overlapping regions. the area of developmental regulatio ...19846392570
further studies on protoplast fusion and interspecific hybridization within the aspergillus nidulans group.hybridization of eight species of the aspergillus nidulans group was attempted using auxotrophic mutants and protoplast fusion methods. viable fusion products were obtained from eight crosses. allodiploid hybrids were recovered from crosses involving a. nidulans with a. rugulosus, a. quadrilineatus, a. nidulans var. echinulatus and a. violaceus, although some mutants only gave heterokaryons. crosses involving these latter species also gave heterokaryons. crosses between a. nidulans and a. unguis ...19846389760
mutants of aspergillus nidulans blocked at an early stage of sporulation secrete an unusual metabolite.mutants of aspergillus nidulans defective in conidiation (asexual sporulation) can be classified according to whether they are blocked before or after induction of conidiation. mutants blocked before induction (preinduction mutants) appear to be unable to respond to the inducing stimulus and thus are defective in one of the earliest events in the sporulation process. three preinduction mutants have been isolated and characterized. each was found to exhibit the same pleiotropic phenotype: they al ...19846389494
induction of somatic segregation by halogenated aliphatic hydrocarbons in aspergillus nidulans.8 halogenated aliphatic hydrocarbons were assayed for their ability to induce somatic segregation in the mould aspergillus nidulans. induction of haploidization, mitotic non-disjunction and mitotic crossing-over was studied in heterozygous colonies exposed to the tested chemicals through the detection and phenotypic analysis of segregated sectors. the results obtained show that 1,2-dibromoethane induced all kinds of segregated sectors; 1,2-dichloroethane, allyl chloride, 2-chloroethanol, 2,2-dic ...19846387478
mutations affecting the sulphur assimilation pathway in aspergillus nidulans: their effect on sulphur amino acid metabolism.several sul-reg mutants of aspergillus nidulans isolated as constitutive for arylsulphatase were studied with respect to the regulation of enzymes involved in cysteine and homocysteine synthesis and to the pool of sulphur amino acids. all mutants examined showed a decreased concentration of glutathione as compared with the wild type, and all mutants, with one exception, had a decreased total pool of sulphur amino acids. the results suggest that the mutants are leaky in the sulphate assimilation ...19846381643
effects of mitotic and tubulin mutations on microtubule architecture in actively growing protoplasts of aspergillus nidulans.we used immunofluorescent microscopy to characterize microtubule (mt) architecture in wild-type and mutant protoplasts of aspergillus nidulans at interphase and at mitosis. because the visualization of mts by immunofluorescence is technically difficult in intact hyphae of a. nidulans, we developed a method for removing the cell wall under conditions that do not perturb cell physiology, as evidenced by the fact that the resulting protoplasts undergo nuclear division at a normal rate and that cell ...19846381507
evidence for a nonsense mutation at the niad locus of aspergillus nidulans. 19846381230
Displaying items 3701 - 3800 of 5149