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allele specific, gene unspecific suppressors in aspergillus nidulans.seven suppressor mutations have been isolated in aspergillus nidulans by coreversion of alleles in physiologically unrelated genes namely, alx, sb, alca, putative structural genes for allantoinase, sulphate permease and alcohol dehydrogenase respectively. the suppressors are allele specific, gene unspecific. those described map in four loci, suaa, b, c, d. suaa and suab are on linkage group iii, suac and suad on vii. suab111, suad103 and suad108 are semi-dominant in their suppression of alx4 and ...1979395416
phenotypes of double conidiation mutants of aspergillus nidulans.a series of strains, doubly mutant at conidiation loci, have been made. the phenotypes of these strains reflected the epistasy of earlier blocking mutants over later ones and confirmed the order of gene sequence predicted from the phenotypes of single mutants. oligosporogenous mutants gave complex interactions, especially between brl and med mutants. these results indicated that (i) gene action overlapped in time, (ii) several parts of the conidial apparatus were interchangeable and (iii) nuclei ...1979396353
evidence that p-fluorophenylalanine has a direct effect on tubulin in aspergillus nidulans.three temperature-sensitive alleles of bena (bena11, 17 and 21) confer resistance to growth inhibition by p-fluorophenylalanine (fpa). fpa resistance cosegregates with the bena gene. two back-mutations in bena which cause loss of temperature sensitivity cause loss of fpa resistance, and two indirect suppressors of bena temperature sensitivity also cause fpa resistance to be lost. these results indicate that fpa resistance is an intrinsic property of the bena mutations. the intracellular phenylal ...1979396355
protoplasts from aspergillus nidulans.a very effective lytic enzyme system for massive micro/macro-scale production of protoplasts from the filamentous fungus aspergillus nidulans is described. a striking coincidence was observed between maximal lytic activity towards aspergillus mycelium and the presece of both chitinase and alpha-(1 leads to 3)-glucanase activities. the release of protoplasts was greatly enhanced by preincubating the mycelium with 2-deoxy-d-glucose. furthermore, protoplast formation was influenced by fungal age, c ...1979399317
an iron-containing superoxide dismutase from anacystis nidulans.superoxide dismutase (sod) was isolated and purified from anacystis nidulans to near electrophoretic homogeneity. the enzyme has a molecular weight of 37,500, as determined by gel filtration and sds-gel electrophoresis. the enzyme molecule consists of two subunits of identical molecular weight. proton-induced x-ray elemental analysis (pixe) showed that the sod of a. nidulans is an iron-containing enzyme; the fe:enzyme mol ratio was found to be 1. the epr spectra indicated that the active center ...1979222743
the dark respiration of anacystis nidulans. production of hcn from histidine and oxidation of basic amino acids.the basic amino acids, l-arginine, l-lysine, lo-irnithine, and to a lesser extent l-histidine, strongly stimulate the o2 uptake of cell suspensions of the blue-green alga or cyanobacterium anacystis nidulans. in the case of l-histidine, the extra o2 consumption is associated with the formation in vivo of small amounts of hcn, particularly in an atmosphere of o2. the enzyme responsible for both the stimulated o2 uptake with the basic amino acids and the formation of hcn from histidine has been is ...1979223652
[metabolic pathways of exogenous pyrimidines in aspergillus nidulans].studies on the susceptibility of the wild-type strain of aspergillus nidulans to 6-azauracil suggest that it synthesizes pyrimidines using a by-pass pathway which is induced with 6-azauracil. the effect of a series of pyrimidines on the toxic action of 5-fluorouracil, 5-fluorouidine and 5-fluorodeoxyuridine has been investigated. as the result of these studies, a scheme is proposed for the metabolism of some pyrimidine bases and nucleosides in aso. nidulans.1979370519
induced quantitative variation for penicillin titre in clonal populations of aspergillus nidulans.the variation in penicillin titre within populations of cultures of aspergillus nidulans derived from untreated conidia and from conidia treated with ethyl methanesulphonate (ems), near-ultraviolet light in the presence of 8-methoxypsoralen (8mop) or n-methyl-n'-nitro-n-nitrosoguanidine (ntg), each at several dose levels, was determined. both mutagentreated and untreated populations showed a continuous distribution of pencillin titres. the population mean titre of the mutagenized populations was ...1979372487
induced segregation in interspecific hybrids of aspergillus nidulans and aspergillus rugulosus obtained by protoplast fusion.interspecific hybrids produced by polyethylene glycol induced fusion of protoplasts from auxotrophic mutants of aspergillus nidulans and aspergillus rugulosus were grown in the presence of the recombinogens benomyl and chloral hydrate to stimulate segregation. the a. nidulans parental strains used had a known genetic marker in each linkage group. hybrids grown on complete medium containing benomyl yielded more segregants. analysis of the segregants showed that the distribution of a. nidulans lin ...1979372762
cis-dominant regulatory mutations affecting the expression of gaba permease in aspergillus nidulans.in aspergillus nidulans expression of the gaba gene, the probable structural gene for the gamma-amino-n-butyrate (gaba) permease, is controlled by induction, via the inta gene, ammonium repression, mediated by the area gene, and probably carbon catabolite repression. regulatory mutations, tightly linked to gaba, were selected by reverting an arear-2 strain on gaba as nitrogen source. these mutations, gabi-1, gabi-2, and gabi-3 result in increased gaba expression and are cis-dominant in their eff ...1979375001
the regulation of hexokinase and phosphoglucomutase activity in aspergillus nidulans.the levels of glucose-6-phosphate and 6-phosphogluconate dehydrogenase in wildtype cells of aspergillus nidulans varied with the carbon and nitrogen source. in general, hexokinase activity did not vary with carbon or nitrogen source. the ammonium derepressed mutant amra1 had only 50% of the wildtype level of hexokinase. phosphoglucomutase activity was low in wildtype cells grown with nitrate, but high in cells grown with ammonium when glucose was the carbon source. a non-inducible mutant, nira-1 ...1979375022
molecular cloning of the 4.2 md ecori fragment of aspergillus nidulans mitochondrial dna.the 4.2 md ecori fragment of aspergillus nidulans mitochondrial dna was cloned using the plasmid pbr 332 as vector and e. coli as host. hitherto unknown sequence of hindiii sites within this region of mitochondrial genome was established.1979375024
the ability of ionizing radiations of different let to induce chromosomal deletions in aspergillus nidulans.conidia, derived from a strain of aspergillus nidulans known to carry a specific chromosomal duplication, were irradiated. the duplicated segment had genetic markers, which, when eliminated from the genome, allowed the easy detection of deletion mutants. survival curves derived following 15 mev electron and gamma-ray irradiation were characterised by the presence of an appreciable shoulder, whilst 50 kvp x-rays gave a much smaller shoulder. irradiation with beta-particles and alpha-particles gav ...1979375074
studies on saprozoonosis. i. a survey on aspergillus species with special reference to occupational habits.a comprehensive survey of aspergillus species has been carried out among different cattle and donkey handlers. a total of 300 pharyngeal swabs of different subjects including 100 control and 100 each from cattle and donkey handlers was investigated. all the subjects were found healthy. among the species of aspergillus, the number of a. flavus appeared higher followed by a. fumigatus, still lower number was encountered with other species like a. nidulans and a. glaucus. in order to establish the ...1979429763
toxic aspergilli from pistachio nuts.pistachio nut samples taken during various stages of development from orchards in iran, showed that contamination with fungi occurred mainly during the later stages of nut development. members of the genera aspergillus and penicillium occurred most frequently. of the aspergilli, the species a. niger, a. flavus and a. fischeri var. spinosus occurred most frequently, followed by a. terreus, a. tamarii and a. nidulans. twenty-two isolates comprising 13 species were tested for toxicity to ducklings. ...1979481560
a new in vitro method for testing plant metabolism in mutagenicity studies.a rapid method was proposed to detect whether a harmless agricultural chemical can be converted into a mutagenic one by plant metabolism. the method is based on the use of nicotiana alata cell cultures. results obtained with five pesticides (atrazine, dichlorvos, tetrachlorvinphos, kelevan, and maleic hydrazide) suggest that the proposed method simulates the metabolism of the whole plant. this procedure was also successfully applied to the genetic system of aspergillus nidulans. one pesticide, a ...1979513148
[the effectiveness of an (aspergillus) differential medium in the course of the mycological examination of foods].the effectiveness of aspergillus differential medium (adm) for the identification of aspergillus strains was tested. the bright yellow-orange pigment was produced by 205 (88,7%) of 231 strains and resp. 97 (61,3%) of 158 strains, which during routine mycologic diagnostic as a.flavus and a.oryzae, respectively. strains of the groups a.clavatus (76), a.glacus (100), a.fumigatus-(9), a.niger-(6), a.candidus-(3), a.wentii-(1), a.versicolor (23), a.nidulans (6), a.ustus (1) and a.terreus (1) gave neg ...1978706813
characterization of a new choline locus in aspergillus nidulans and its significance for choline metabolism. 1978376401
virulence genetics of aspergillus nidulans eidam: a review.studies of the influence of genotypic alterations on the murine virulence of aspergillus nidulans eidam are reviewed to emphasize the potential of this fungus for genetic studies of virulence.1978370604
polyamine stimulation of in vivo rates of macromolecular synthesis in a putrescine auxotroph of aspergillus nidulans. 1978340271
preparation of large molecular weight dna from the fungus aspergillus nidulans. 1978353226
multiple independent control mechanisms affecting the acetamidase of aspergillus nidulans.the acetamidase of aspergillus nidulans is induced by sources of acetyl coa, benzoate and benzamide and by beta-alanine and other omega-amino acids. the effects of these groups of inducers are appromimately additive. the cis-acting control site mutant, amdi9, affects induction by sources of acetyl-coa specifically. lesions in the amdr and gata genes affect induction by omega-amino acids specifically. mutations in the amda gene can lead to elevated acetamidase levels which still respond to the va ...1978353500
detection of mutagens produced by fungi with the salmonella typhimurium assay.forty-one fungal isolates (one isolate per species) representing common plant pathogens and food crop contaminants were grown on sterile, polished rice and assayed for mutagenic activity in the salmonella typhimurium-microsome system. initially, single doses of aqueous and chloroform extracts of the moldy rice were assayed against the ta100 tester strain by incorporating extracts into the growth medium and by applying small quantities on disks placed on the agar surface. suspected activity was e ...1978354528
reduced expression of a distal gene of the prn gene cluster in deletion mutants of aspergillus nidulans: genetic evidence for a dicistronic messenger in an eukaryote.the prn gene cluster involved in l-proline catabolism in aspergillus nidulans, has the gene order prna-prnd-regulatory region-prnb-prnc. prnb, prnd, and prnc specify proline permease, proline oxidase, and delta1-pyrroline-5-carboxylate (p5c) dehydrogenase, respectively. prna is probably a positive regulatory gene whose product is necessary for expression of the prn activities. proline induces proline permease and p5c dehydrogenase in prnd- mutants which lack proline oxidase, showing that proline ...1978355839
gaba transaminase provides an alternative route of beta-alanine synthesis in aspergillus nidulans.three unlinked genes where mutation can lead to d(+)-pantothenic acid auxotrophy in aspergillus nidulans have been identified. pantoa is probably the structural gene for pantothenate synthetase (ec 6.3.2.1) whilst pantob and pantoc are involved in the syntheses of d-pantoic acid and beta-alanine, respectively. a pantoc- mutant is tentatively considered to be blocked in conversion of 5,6-dihydrouracil to beta-ureidopropionate. an alternative route of beta-alanine biosynthesis occurs by the transa ...1978355840
distribution of autolysins in hyphae of aspergillus nidulans: evidence for a lipid-mediated attachment to hyphal walls.preparations of broken aspergillus nidulans hyphae contained both free and wall-bound autolysins. the bound enzymes were not solubilized by 8 m licl or neutral or anionic detergents; they were readily detached from walls by a cationic detergent or by autodigestion. once detached, the enzymes did not reassociate with wall to give salt-resistant complexes. six enzymes hydrolyzing wall polymers were bound to the envelope, and the same activities were also detected among soluble proteins in the cyto ...1978357422
on the mechanisms of induced somatic recombination by certain fungicides in aspergillus nidulans.four fungicides interfered with the segregation of chromosomes at mitosis of aspergillus nidulans by increasing the somatic recombination, shown as colour sectors in green colonies, in a strain heterozygous for spore colour mutations. in an attempt to discover the mechanisms by which these fungicides increased the somatic recombination, a prototrophic diploid strain, heterozygous for colour and several other appropriate markers in all chromosomes, was used which enabled the detection and classif ...1978357961
interaction of thiabendazole with fungal tubulin.thiabendazole, 2-(4'-thiazolyl)benzimidazole, at 80 micrometer completely inhibits mitosis in hyphae of aspergillus nidulans, growing in liquid culture. dna and rna synthesis and mycelial growth are only partially inhibited at this concentration. binding studies with cell-free mycelial extracts from penicillium expansum showed that thiabendazole competitively inhibits [14c]carbendazim binding to tubulin, which suggests that the antimitotic activity of thiabendazole is based on interference with ...1978361093
pyridoxine and its relation to lipids. studies with pyridoxineless mutants of aspergillus nidulans.the effect of pyridoxine deficiency on fat metabolism was studied using mutant strains of aspergillus nidulans requiring pyridoxine for growth. under pyridoxine deficiency the mutants exhibited increased levels of total lipid, sterols, phospholipids, and triacylglycerols. total fatty acids were found to decrease with pyridoxine deficiency. an increase in saturated fatty acids and decrease in unsaturated fatty acids were seen with deficiency. pyridoxine deficiency also increased lower carbon chai ...1978361929
reversion in variants from a duplication strain of aspergillus nidulans.strains of aspergillus nidulans with a chromosome segment in duplicate, one in normal position and one translocated to another chromosome, are unstable at mitosis. in addition to variants which result from deletions in either of the duplicate segments, which usually have improved morphology, they produce variants with deteriorated morphology. three deteriorated variants reverted frequently to parental type morphology, both spontaneously and after ultra-violet treatment. of six reversions analyse ...1978362154
a mutation defective in the xanthine alternative pathway of aspergillus nidulans: its use to investigate the specificity of uay mediated induction.in aspergillus nidulans uric acid can be produced from xanthine via purine hydroxylase i (xanthine dehydrogenase) or via the xanthine alternative pathway (darlington and scazzocchio, biochem. biophys. acta, 166, 569--571; 1968). a mutation defective in the xanthine alternative pathway of aspergillus nidulans is described. by combining this mutation with hxb-20 which results in complete loss of purine hydroxylase i and ii activities, but which conserves cross-reacting material, it is possible to ...1978362158
a quick method for testing recessive lethal damage with a diploid strain of aspergillus nidulans.a simple method capable of detecting recessive lethal damage in a diploid strain of aspergillus nidulans is described. the method scores the recessive lethals on the 1st, the 3rd and the 5th chromosomes, which represent about 40% of the total map of a. nidulans. two examples of induced lethals, with ultraviolet irradiation and methyl methanesulfonate are shown. the frequency of lethals may reach 36% of the total population with uv irradiation.1978362184
low repetitive dna content in aspergillus nidulans.dna-dna reassociation experiments show that the genome of aspergillus nidulans consists of approximately 97 to 98 percent unique and 2 to 3 percent reiterated sequences. the reiterated dna sequences have a complexity of about 11,000 base pairs and are repeated approximately 60 times per haploid genome. ribosomal rna-dna hybridization experiments indicate that most of the repetitive dna codes for ribosomal rna.1978362530
[methodological approaches to the study of ultraviolet irradiation--induced dna degradation in mycelial fungi using the example of aspergillus nidulans]. 1978363179
identification of a gene for beta-tubulin in aspergillus nidulans. 1978363278
the genetic control of the molybdoflavoproteins in aspergillus nidulans. iv. a comparison between purine hydroxylase i and ii.the purine hydroxylases i and ii of aspergillus nidulans [previously called xanthine dehydrogenases i and ii: scazzocchio, holl and foguelman, eur. j. biochem. 36, 428--445 (1973)] have been studied in crude extracts. the two enzymes differ in their substrate specificities, purine hydroxylase ii being able to accept nicotinate as a substrate and unable to hydroxylate xanthine. the kinetics of inhibition with allopurinol and oxypurinol are also different, the two analogues being pseudo-irreversib ...1978363427
a mutation in the xanthine dehydrogenase (purine hydroxylase i) of aspergillus nidulans resulting in altered specificity. implications for the geometry of the active site.a point mutation in the structural gene for purine hydroxylase i (xanthine dehydrogenase) of aspergillus nidulans results in several dramatic pleiotropic effects. the mutant enzyme oxidises 2-hydroxypurine at position 6 rather than 8, shows a 70-fold reduction in the v for hypoxanthine, and loses the ability to accept xanthine as a substrate. allopurinol, a powerful pseudoirreversible inhibitor of the wild type enzyme, behaves as a good substrate of the mutant enzyme. we propose that the substra ...1978363429
[isolation and genetic study of aspergillus nidulans mutants defective in pyrimidine biosynthesis].8 uridine-requiring pyr mutants were isolated from aspergillus nidulans under nitrosoguanidine treatment. all the mutants are capable to grow on the medium containing 20 mkg/ml of uridine or cytidine, or 100 mkg/ml of uracil, and they do not utilize thymidine, thymine, cytosine and deoxyuridine. their ability to grow in the presence of orotic acid demonstrates that the pyrimidine synthesis in all the mutants is blocked at stages preceding the conversion of orotic acid into orotidine monophosphat ...1978363504
a hydroxamic acid from aspergillus nidulans with antibiotic activity against proteus species.an iron-complexing antibiotic with a narrow spectrum of biological activity was produced by several strains of aspergillus nidulans when grown in a low-iron, chemically defined medium. its chemical and biological properties closely resembled those of desferritriacetylfusigen, a metabolite of several other aspergilli and penicillia.1978363670
isolation of dna from aspergillus nidulans.a procedure for isolation of dna from aspergillus nidulans on a preparative scale is described. mechanical disruption of lyophilized material in high-salt medium and treatment with proteinase k, followed by sedimentation of the lysate into saturated csc1 solution yielded pure, highly polymerized dna.1978364902
[presence of sexual forms (cleistothecia and hülle cells) in a case of human maxillary sinus aspergillosis caused by aspergillus nidulans in association with aspergillus fumigatus].the authors observed, in a biopsic sample from a human maxillary sinus, the coexistence, in parasitic stages, of two different aspergillus species: a. fumigatus and a. nidulans. after having described the morphologies of each species, in sections on slides, and particularly those of cleistothecia and hülle-cells for the second, they draw attention to the three interests of such an observation: -- rarety of observing aspergillus nidulans in a parasitic stage, in spite of its particular thermotole ...1978366429
aspects of the molecular biology of lipoamide dehydrogenase. 1978367117
an "up-promotor" mutation affecting the acetamidase of aspergillus nidulans.a derivative of an area200 strain of aspergillus nidulans selected for strong growth on acetamide as the sole nitrogen source was found to have a mutation, amd-18, closely linked to amds, the acetamidase structural gene. this mutation results in 2--3 fold higher acetamidase activities than wildtype strains in uninduced as well as induced cultures. the effects of the amd-18 mutation are superimposed on the effects of other regulatory mutations affecting the acetamidase. the amd-18 mutation is cis ...1978368568
lactam utilisation in aspergillus nidulans: evidence for a fourth gene under the control of the integrator gene inta.mutations in the lama gene of aspergillus nidulans prevent the conversion of exogenous 2-pyrrolidone (gamma-butyrolactam) to gamma-amino-n-butyrate (gaba) and also prevent the (probably analogous) utilisation of 2-piperidone (sigma-valerolactam). the lama gene, in linkage group viii, probably specifies a lactamase but a rôle in lactam uptake cannot be ruled out. lama is probably under the control of the positive acting regulatory gene inta, which can integrate its expression with the expression ...1978368580
regulatory properties of pyruvate carboxylase from aspergillus nidulans: evidence for the presence of a masked activator site [proceedings]. 1978369914
[use of a pyrimidine-dependent mutant for effective labeling of the dna of aspergillus nidulans].incorporation of the radioactive label from pyrimidines into rna and dna of an aspergillus nidulans pyrimidine-dependent mutant was studied. the label from [14c2]uridine was incorporated at the highest rate into both fractions of nucleic acids from a. nidulans of the wild type and pyr-mutant. the content of the label in the dna of the pyr-mutant was several times higher than that in the wild type dna. therefore, pyr-mutants can be used in order to study molecular-genetic processes in the cells o ...1978370508
cell cycle mutants. 1978106766
phycobiliprotein synthesis in protoplasts of the unicellular cyanophyte, anacystis nidulans.stable and metabolically active protoplasts were prepared from the unicellular cyanophyte, anacystis nidulans, by enzymatic digestion of the cell wall with 0.1% lysozyme. the yield of protoplasts from intact algal cells was approx. 50%. incorporation of l-[u-14c]leucine into cold trichloroacetic acid-insoluble material from protoplasts preparations was linear for 1.5 h and continued for an additional 2.5 h. incorporation of radiolabeled leucine into hot trichloroacetic acid-insoluble material fr ...197896857
catabolite repression in aspergillus nidulans; the role of glutamine synthetase.a mutant (nit8) with a lowered activity of glutamine synthetase (gs) was isolated in aspergillus nidulans. the levels of gs and of an arginine catabolic enzyme, ornithine transaminase (ota) were assayed under a variety of growth conditions leading to repression, depression and induction of ota in the wild type, nit8 and several regulatory mutants. the results obtained appear to exclude the possibility of involvement of gs in the regulation of arginine catabolism in a. nidulans.197886277
nitrate assimilation in fungi. 1978157059
meiotic recombination in a duplication strain of aspergillus nidulans. 1978344133
the effects of coumarin on the frequency of deletions in a duplication strain of aspergillus nidulans.strains of a. nidulans with a chromosome segment in duplicate show instability resulting from deletions in either of the duplicate segments. in dp (i, ii) strains, with the terminal segment of ir attached terminally to iir, spontaneous deletions occur most frequently, though not exclusively, from the translocated segment. coumarin, at concentrations which did not affect viability viability or growth rate, enhanced the instability of dp (i, ii) strains by selectively increasing only the deletion ...1978345093
supersuppressors in aspergillus nidulans.simultaneous reversion of mutations in two different aspergillus nidulans loci ada and metg was found to be due monogenic suppressor mutations. preliminary evidence for the existance of supersuppressors in a. nidulans is presented.1978345096
restriction endonuclease cleavage map of mitochondrial dna from aspergillus nidulans.mitochondrial dna of the ascomycete fungus aspergillus nidulans, a circular molecule of 31 500 base pairs, is cleaved by restriction endonucleases eco r i, hind ii, hind iii and bgl ii into 3, 7, 9 and 5 fragments, respectively. the relative positions of the cleavage sites could be mapped by analysis of fragments obtained by double enzyme digestions of whole dna and by complete and partial redigestion of isolated restriction fragments.1978345242
mutations in nira gene of aspergillus nidulans and nitrogen metabolism. 1978347305
sporulation competence in aspergillus nidulans: a role for iron in development.there is a difference in the response of dna from mycelial extracts of aspergillus nidulans to hot acid hydrolysis depending upon the state of sporulation competence. the dna in incompetent culture mycelia is not hydrolyzable while the dna in competent culture is hydrolyzable. the inhibition of dna hydrolysis is due to the presence of iron. although the concentration of iron decreases in mycelia during growth, there is sufficient iron present in competent mycelia to inhibit dna hydrolysis. the c ...1978350417
the nature of an initiator constitutive mutation in aspergillus nidulans. 1978351427
adsorption of cyanophage as-1 to unicellular cyanobacteria and isolation of receptor material from anacystis nidulans.cells of unicellular cyanobacteria of typological group ia, containing approximately 50 mol% guanine + cytosine (g+c) in their dna (r. y. stanier, r. kunisawa, m. mandel, and g. cohen-bazire, bacteriol. rev. 35:171-205, 1971), were susceptible to infection by the cyanophage as-1. cyanobacteria of the same typological group, containing approximately 65 mol% g+c in their dna, did not adsorb the cyanophage as-1 or adsorbed it at a low rate. as-1 was not propagated by any of the investigated strains ...1978413935
culture and antigen variants of aspergillus. 1978416063
[genetic control of the sensitivity of aspergillus nidulans to mutagenic factors. vii. inheritance of cross-sensitivity to different mutagenic factors by uvs-mutants].to study the inheritance of the sensitivity to uv, x-rays, methylmethanesulphonate (mms), nitrosoguanidine (ng) and nitrous acid (na) in five uvs mutants of aspergillus nidulans, having multiple sensitivity to these factors, the sensitivity of recombinants obtained from crossing uvs mutants with uvs+ strain, resistant to all the factors analysed, and uvs leads to uvs+ revertants is investigated. four uvs mutants (15, 17, 19 and 26) are found to have a nomogenic control of sensitivity to differen ...1977352800
identification of an intramitochondrially synthesized proteolipid associated with the mitochondrial atpase complex as the product of a mitochondrial gene determining oligomycin resistance in aspergillus nidulans. 1977142636
nuclear-extranuclear interactions affecting oligomycin resistance in aspergillus nidulans.the extranuclear mitochondrial oligomycin-resistant mutation of aspergillus nidulans, (olia1), was transferred asexually into four nuclear oligomycin-resistant strains of different phenotypes. in all four cases, the possession of the nuclear plus extranuclear mutation led to an increase in the in vivo level of oligomycin resistance. in two cases, the altered cytochrome spectrum and impaired growth ability determined by (olia1) were suppressed by the nuclear mutations. in the third case, the in v ...1977144864
effect of growth temperature on the cell constituents of aspergillus nidulans. 1977202564
genetic damage induced by ethyl alcohol in aspergillus nidulans.heterozygous diploid conidia of aspergillus nidulans were treated during germination with ethyl alcohol in concentrations ranging from 0.25% to 20% (v/v). the diploid strain carried three recessive conidial color mutations, in addition to genetic markers on all eight pairs of linkage groups. it was thereby possible to detect events of crossing over, non-disjunction, and mutation. an increase in the dose of ethanol was associated with a decrease in conidial viability and an increase in the relati ...1977319353
pleiotropic mutants of aspergillus nidulans altered in carbon metabolism.mutants altered in carbon catabolite regulation have been isolated by selecting for mutants of the area217 strain capable of using acetamide as the sole nitrogen source in the presence of sucrose. in addition to crea mutants described previously be arst and cove, strains with mutations in two new genes, creb and cre c, have been found. the creb and crec mutants grow poorly on some sole carbon sources and have low levels of some enzymes of carbon catabolism e.g. beta-galactosidase and d-quinate d ...1977320455
interspecific protoplast fusion and complementation in aspergilli. 1977321242
two unlinked genes for the pyruvate dehydrogenase complex in aspergillus nidulans.the activity of the overall pyruvate dehydrogenase complex was found to be similar in extracts of aspergillus nidulans after growth on either sucrose or acetate. eight mutants lacking the activity of this complex were found among some 200 glycolytic mutants selected for their inability to grow on sucrose. the absence of pyruvate dehydrogenase complex activity was also confirmed for a mutant, g6 (pdha1), isolated previously. studies with the mutants supported the existence of two unlinked genes, ...1977321417
effects of ethidium bromide in diploid and duplication strains of aspergillus nidulans.unstable duplication and diploid strains of aspergillus nidulans were treated with ethidium bromide, and it was shown that this drug reduces the number of sectors produced by such strains. the mechanisms which could be responsible for the partial stabilization of the strains are discussed and it is suggested that a similar mechanism is responsible for the production of sectors in both strains. it is also suggested that ethidium bromide could be useful for the reduction of instability of industri ...1977323033
the effects of 1,4-diaminobutanone on polyamine synthesis in aspergillus nidulans. 1977323046
some genetical aspects of ornithine metabolism in aspergillus nidulans.a possible minor route of ornithine catabolism in aspergillus nidulans might begin with the ornithine decarboxylase reaction and end with the succinic semialdehyde dehydrogenase reaction. it is therefore of interest that the putative structural genes for these two enzymes, pua and ssua, respectively, are tightly linked group ii. however, this linkage is unlikely to have regulatory significance because ilea, the structural gene for threonine dehydratase, separates them. the gene order in this reg ...1977325361
resistance and mitotic instability to chloroneb and 1,4-oxathiin in aspergillus nidulans.mutants resistant to two fungicides, chloroneb (1,4-dichloro-2,5-dimethoxybenzene) and vitavax (2,3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin) were spontaneously obtained from a strain of aspergillus nidulans with frequencies of 12.5 and 1.1 respectively, in 10(8) conidia. one chloroneb-resistant mutant (chl 1) segregated as a single gene and was mapped in linkage group iv. it also caused a partial dependence of the strain on the fungicide and was semi-dominant. the mutant resistant to vitav ...1977327307
meiotic and mitotic recombination in aspergillus and its chromosomal aberrations. 1977327767
the genetic control of molybdoflavoproteins in aspergillus nidulans. a xanthine dehydrogenase i half-molecule in cnx- mutant strains of aspergillus nidulans.the cnx- group of mutants of aspergillus nidulans lacks xanthine dehydrogenase (xanthine: nad+ oxidoreductase, ec 1.2.1.37) and nitrate reductase (ec 1.6.6.3) activities and are thought to be defective in the synthesis of a molybdenum-containing cofactor, 'cnx', common to xanthine dehydrogenase and nitrate reductase [pateman, j.a., rever, b.m., cove, d.j. and roberts, d.b. (1964) nature (lond.) 201, 58-60]. the cnx cofactor has a role in maintaining the aggregated multimeric structure of nitrate ...1977330163
regulation of glucose transport in aspergillus nidulans.pyruvate and acetate inhibited the uptake of glucose by aspergillus nidulans; although there were significant variations in glucose uptake rate, the intracellular concentration of acetate was almost identical in biotin-supplemented, normal and deficient cells. the in vitro activity of glucose-binding protein was not affected by biotin, avidin, acetate or acetyl-coa.1977330193
l-asparaginase activity in the fungus aspergillus nidulans. 1977330277
[genetic control of recombination processes in aspergillus nidulans. i. effect of uvs-mutations on the frequency of spontaneous and ultraviolet ray-induced intergenic recombination].effect of 3 uvs mutations (uvs 12, 19 and 25) on recombination processes in aspergillus nidulans is studied. all the mutations are found either to affect the fertility of carp bodies and germination ability of askospores, or result in complete inability of heterokaryons to form cleistocarpia. two mutations change the frequency of spontaneous meitotic crossing-over at pro-paba region of the chromosome i and do not affect the rate of mitotic recombination at w-centromeric region of the chromosome ...1977330315
recent advances in basic mutation research. 1977331099
the metabolism of phenylacetic acid by aspergillus fumigatus atcc 28282: identification of 2,6-dihydroxyphenylacetic acid.aspergillus fumigatus atcc 28282 converted phenylacetic acid into a new dihydroxylated compound (2,6-dihydroxyphenylacetic acid) which was identified as 2,6-dimethoxyphenylacetic acid methyl ester. two other new metabolites have been isolated also and identified as orthohydroxyphenylacetic acid and meta-hydroxyphenylacetic acid.1977332293
[ultrastructural investigations on antimitotic activity of methylbenzimidazol-2-ylcarbamate (mbc) and its influence on replication of the nucleus-associated organelle ("centriolar plaque", "mtoc", "kce") in aspergillus nidulans (author's transl)]. 1977333514
aspergillus nidulans mutant lacking alpha-(1,3)-glucan, melanin, and cleistothecia.a mutation in aspergillus nidulans led to a loss of both melanin and alpha-(1,3)-glucan, a major wall polysaccharide. in addition, the mutation prevented the formation of cleistothecia. mutant walls contained increased amounts of beta-(1,3)-glucan and galactose polymers, and electron micrographs indicated that they had lost the outermost wall layer. such walls were more readily digested by lytic enzymes, and this increased susceptibility to hydrolysis was due to the absence of alpha-(1,3)-glucan ...1977334748
the induction of mutations to 2-thioxanthine resistance in inhibitor depleted conidia of aspergillus nidulans by gamma-radiation in the presence of oxygen or nitrogen.a strain of aspergillus nidulans has been used to study the inactivating and mutagenic effect of 60cogamma-rays in the presence of oxygen or nitrogen. mutation was studied by the 2-thioxanthine system which selectively detects forward mutation at a number of gene loci (at least 16). mutants resistant to conidial pigmentation effects of 2-thioxanthine can be divided into four main classes (2txr, hx, uay and cnx) and three of these classes (hx, uay and cnx) can be further characterized at the gene ...1977335238
the basis for an apparent auxotrophy for reduced sulphur metabolites in sf- mutants of aspergillus nidulans. 1977336463
a mutation in aspergillus nidulans which affects the regulation of nitrite reductase and is tightly linked to its structural gene. 1977337118
regulation of ammonia uptake in aspergillus nidulans.the ammonia uptake in a. nidulans was found to be linear for about 20 min, and was proportional up to 1.5 mg/ml dry cell density. the transport of ammonia does not involve energy. normal and biotin deficient a. nidulans showed an identical km-values of 10.26 x 10(-5) m ammonia for uptake. the uptake of ammonium ion has been shown to be regulated by the intracellular concentration of ammonia.1977338337
the effect of 1,4-diaminobutanone on the stability of ornithine decarboxylase from aspergillus nidulans.1,4-diaminobutanone, a competitive inhibitor of ornithine decarboxylase in aspergillus nidulans, is able to increase the half-life of this enzyme and thus stimulate an increase in its activity in vivo. it also protects ornithine decarboxylase against proteolysis by chymotrypsin in vitro.1977339910
differential binding of methyl benzimidazol-2-yl carbamate to fungal tubulin as a mechanism of resistance to this antimitotic agent in mutant strains of aspergillus nidulans.the antimitotic compound methyl benzimidazol-2-yl carbamate (mbc) formed a complex in vitro with a protein present in mycelial extracts of fungi. the binding protein of aspergillus nidulans showed a set of properties which is unique for tubulin. binding occurred rapidly at 4 degrees c and was competitively inhibited by oncodazole and colchicine. other inhibitors of microtubule function such as podophyllotoxin, vinblastine sulfate, melatonin, and griseofulvin did not interfere with binding of mbc ...197712184
in vivo and in vitro studies of nitrate reductase regulation in asperillus nidulans.induced wildtype cells of a. nidulans rapidly lost nadph--linked nitrate reductase activity when subjected to carbon and or nitrogen starvation. a constitutive mutant at the regulatory gene for nitrate reductase, nir ac 1, rapidly lost nitrate reductase activity upon carbon starvation. this loss of activity is thought to be due to a decrease in the nadph concentration in the cells. cell free extracts from wildtype cells grown in the presence of nitrate, rapidly lost their nitrate reductase activ ...197717826
induction of the acetamidase of aspergillus nidulans by acetate metabolism.growth tests and enzyme determinations strongly suggest that the acetamidase of aspergillus nidulans is induced by a product of acetate metabolism rather than the substrate, acetamide. the cis-dominant mutation, amdi9, which is closely linked to amds, the structural gene for the acetamidase, results in greatly increased sensitivity to induction by acetate metabolism. propionate, l-threonine, and ethanol also result in acetamidase induction. mutations in the faca, facb, and facc genes, which lead ...197719418
mutagenic and recombinogenic action of pesticides in aspergillus nidulans.thirteen pesticides, aminotriazole, benomyl, captafol, captan, dalapon-na, dichlorvos, dinobuton, dodine, ioxynil, mecoprop, neburon, picloram and tordon were tested for ability to induce (1) point mutations to 8-azaguanine resistance, (2) mitotic crossing-over, and (3) mitotic non-disjunction and haploidization in aspergillus nidulans. tests were performed at three different phs, i.e. 4.5, 7, 8.2. three of the pesticides, captan , captafol and dichlorvos induced point mutations; dichlorvos also ...197722812
increased and decreased sensitivity to carbon catabolite repression of enzymes of acetate metabolism in mutants of aspergillus nidulans.the crea204, creb15 and crec27 mutations have been shown to cause carbon catabolite derepression of acetly coa synthase and isocitrate lyase in aspergillus nidulans. a recessive mutation, cre-34, which is linked to the crec gene, results in these enzymes being more sensitive than cre or wildtype strains to catabolite repression. the acetamidase levels of strains containing cre mutations have been investigated and provide support for the hypothesis that an acetate metabolite, rather than acetamid ...197723491
genetic analysis of mutations of low (rec) and very high (pop) mitotic-recombination frequency in aspergillus nidulans. 1977340885
extranuclear recombination in aspergillus nidulans: closely-linked multiple chloramphenicol- and oligomycin-resistance loci.a nuclear, chloramphenicol-sensitive mutant cas-1 has been isolated which is cross sensitive to a number of drugs, including oligomycin and cycloheximide. approximately one-third of the chloramphenicol-resistant mutants isolated from mutagenized conidia of this strain were found to be extranuclear, and exhibited a variety of phenotypes. one of these mutants, designated (camb51), was slow growing on drug-free medium and recombined at low frequency with the previously described mutant (cama112) (g ...1977340908
growth, glucose metabolism and melanin formation in biotin-deficient aspergillus nidulans.biotin deficiency resulted in an increased growth rate of aspergillus nidulans. the activities of hexokinase and aldolase were not much changed during the growth cycle, but activities of glucose-6-phosphate dehydrogenase and nadp-linked glutamate dehydrogenase increased significantly during the exponential phase. this change was remarkable during biotin deficiency. in contrast to the higher growth rate and respiration rate during biotin deficiency the activities of nad(p)h oxidoreductases were l ...1977402307
glucan common to the microcyst walls of cyst-forming bacteria.chemical analysis indicated that d-glucose is tha major neutral monosaccharide present in the microcysts of a range of gram-negative bacteria. varying amounts of other neutral sugars were found. the glucose was mainly present as a glucan that could be extracted from microcysts of representative strains with alkali or mild acid treatment. the glucan could be identified as an alpha-1,3-linked polymer on the basis of (i) periodate resistance of the extracted polymer and the material present in micr ...1977402353
temperature dependence on the delayed fluorescence of chlorophyll a in blue-green algae.1. the delayed fluorescence of chlorophyll a was measured with a phosphoroscope by changing the temperature in a range of room temperatures in intact cells of blue-green algae, anacystis nidulans, two strains of anabaena variabilis and plectonema boryanum, and other kinds of algae, cyanidium caldarium and chlorella pyrenoidosa. the induction of delayed fluorescence remarkably depended on the temperature of measurment. nevertheless, the induction pattern was characterized by three levels of inten ...1977403943
interference of cellular ferric ions with dna extraction and the application to methods of dna determination. 1977405886
photosynthetic activity of diimidoester-modified cells, permeaplasts, and cell-free membrane fragments of the blue-green alga anacystis nidulans.on treating the blue green alga anacystis nidulans with dimethylsuberimidate up to 70% of the free nh2 of the photosynthetic membrane is amidinated, and presumably inter- and intramolecular cross-links are established in the membrane proteins. amidination destroys the ability of a. nidulans to photoreduce hco3(-) but leaves the photochemical activities of photosystems ii and i nearly intact. with added electron acceptors, photosynthetic o2 evolution can be demonstrated both with permeable cells ...1977409432
occurrence of a major protein associated with fruiting body development in neurospora and related ascomycetes.electrophoretic and immunological analysis of fruiting body (perithecial) extracts demonstrates the occurrence of a major phase-specific perithecial protein in all neurospora species and in the closely related gelasinospora cerealis and sordariafimicola. the perithecial proteins from these different species fall into a number of groups with different electrophoretic mobilities. they appear to be immunologically closely related but not identical to one another even within the same genus, with onl ...1977410027
basic and neutral amino acid transport in aspergillus nidulans.arginine and methionine transport by aspergillus nidulans mycelium was investigated. a single uptake system is responsible for the transport of arginine, lysine and ornithine. transport is energy-dependent and specific for these basic amino acids. the km value for arginine is 1 x 10(-5) m, and vmax is 2-8 nmol/mg dry wt/min; km for lysine is 8 x 10(-6) m; kt for lysine as inhibitor of arginine uptake is 12 mum, and ki for ornithine is mm. on minimal medium, methionine is transported with a km of ...19761466
analysis of acetate non-utilizing (acu) mutants in aspergillus nidulans.genetic analysis of 119 acetate non-utilizing (acu) mutants in aspergillus nidulans revealed ten new loci affecting acetate metabolism in addition to the three previously recognized on the basis of resistance to fluoroacetate and acetate non-utilization. the enzyme lesions associated with mutations at seven of the acu loci are described. these are: faca (= acua), acetyl-coa synthase; acud, isocitrate lyase; acue, malate synthase; acuf, phosphoenolpyruvate carboxykinase; acug, fructose 1,6-diphos ...19763622
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