a modified minimal medium for aspergillus nidulans. 1975328
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
assimilation of ammonia and growth of biotin deficient aspergillus nidulans.biotin deficiency in aspergillus nidulans has been found to increase the uptake of ammonium ions, associated with a marked increase in the activity of nadp-linked glutamate dehydrogenase, which is found to be the major route of ammonia assimilation in this culture. the results obtained are discussed with respect to the growth of aspergillus nidulans during biotin deficiency.19765283
chlorate toxicity in aspergillus nidulans. studies of mutants altered in nitrate had previously been held that chlorate is not itself toxic, but is rendered toxic as a result of nitrate reductase-catalysed conversion to chlorite. this however cannot be the explanation of chlorate toxicity in aspergillus nidulans, even though nitrate reductase is known to have chlorate reductase activity. among other evidence against the classical theory for the mechanism of chlorate toxicity, is the finding that not all mutants lacking nitrate reductase are clorate resistant. both chlorat ...19768697
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
further characterization of the reduced nicotinamide adenine dinucleotide phosphate: nitrate oxidoreductase in aspergillus nidulans.the reduced nicotinamide adenine dinucleotide phosphate (nadph):nitrate oxidoreductase (ec from aspergillus nidulans wild-type bi-1 was purified by means of salt fractionation, gel filtration, affinity chromatography, and polyacrylamide gel electrophoresis. enzyme which was adsorbed on cibacron blue agarose could be eluted with 2 mm nadph or 2 mm oxidized nadp (nadp(+)), the former being about three times more effective than the latter. about half the total nadph:nitrate reductase activ ...197933144
factors affecting protein synthesis during biotin deficiency in aspergillus nidulans.biotin deficiency in aspergillus nidulans resulted in a 70% increase of the protein content and increased levels of free and bound aspartate, glutamate, serine, leucine and methionine. likewise, the activities of nadp+ glutamate dehydrogenase, nad+ gluatmate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were significantly increased. the total rna content increased while the dna content was unaffected. the rrna/trna ratio remained higher in biotin-deficient cells. supplem ...197943277
phenotypic changes in the chemistry of aspergillus nidulans: influence of culture conditions on mycelial composition.a quantitative study was made of macromolecular (nucleic acids, protein), carbohydrate and mineral (magnesium, potassium and phosphorus) components of aspergillus nidulans in glucose limited chemostat cultures, under varying conditions of dilution rate, temperature, ph and nacl concentration. the overall mineral content showed greatest variation in response to changes in culture salinity, which also affected the mycelial carbohydrate content. concomitant and opposite changes in the content of ca ...197944181
studies on the role of the area gene in the regulation of nitrogen catabolism in aspergillus nidulans.mutants of apergillus nidulans with lesions in a gene, area (formerly called amdt), have been isolated by a variety of different selection methods. the area mutants show a range of pleiotropic growth responses to a number of compounds as sole nitrogen sources, but are normal in utilization of carbon sources. the levels of two amidase enzymes as well as urease have been investigated in the mutants and have been shown to be affected by this gene. most of the area mutants have much lower amidase-sp ...197552352
effect of the area gene on regulation of arginine catabolism in aspergillus nidulans.the area gene which is known to be involved in ammonium repression in aspergillus nidulans was found to participate in regulation of arginine catabolism. mutations in this gene are hypostatic to mutations in arca, sudpro and suepro genes which are responsible for regulation of synthesis of arginine catabolic enzymes.197662492
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
characterization of antigens from aspergillus fumigatus. iii. comparison of antigenic relationships of clinically important aspergilli.antigenic relationships between strains of aspergillus fumigatus, aspergillus fumigatus var. elipticus, aspergillus phialiseptus, aspergillus flavus, and aspergillus niger were analyzed by fused rocket immunoelectrophoresis and by skin tests. seventy-three to 89 % of the numbers of antigens detected between strains and species of the a. fumigatus series were shared. the degree of sharing between antigens of a. flavus, a. fumigatus series, and a. niger was much lower and ranged from 19 to 35 %. i ...197992906
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
effect of growth temperature on lipid and fatty acid compositions in the blue-green algae, anabaena variabilis and anacystis nidulans.the lipid composition was affected by growth temperature in anacystis nidulans, but was not in anabaena variabilis. a. variabilis contained fatty acids of 18 and 16 carbon atoms, which were localized at 1- and 2-positions, respectively, of the glycerol moiety of lipids. desaturation of c18 acids was affected by the growth temperature. a. nidulans contained fatty acids of 14, 16 and 18 carbon atoms. monounsaturated and saturated acids were esterified mainly to 1- and 2-position, respectively. des ...1979104734
cell cycle mutants. 1978106766
photoreactivation of ultraviolet irradiated blue-green alga: anacystis nidulans and cyanophage as-1.ultraviolet (uv) inactivation and photoreactivation of anacystis nidulans and cyanophage as-1 was studied at different wavelengths. uv inactivation of free phage particles and one and two hour host-phage complexes (intracellular phages) were exponential. uv resistance of plaque forming units was attained at the latter phase of latent period. black, blue and white lights were able to photoreactivate the uv irradiated a. nidulans whereas green, yellow and red lights were not. however, incubation o ...1979110290
[effect of lysozyme, ethylenediaminetetraacetate, magnesium and mannittol on spheroplast formation in anacystis nidulans].three periods (the lag period and periods of intensive and decelerated spheroplast formation) can be detected in the action of lysozyme on the cells of anacystis nidulans; this seems to be due to peculiarities in the cell wall structure of the cyanobacterium and heterogeneity of the culture. edta at concentrations of 0.175--0.7 mm has effect on the duration of the lag period but increases the rate of spheroplast formation during the subsequent periods. however, the action of edta in complex with ...1979113653
[fungi in pulmonary pathology].the author presents the most frequently observed pulmonary infections due to some opportunistic fungi (yeast, aspergillus, mucor). he describes the criterial for a correct diagnosis of pulmonary mycosis.1979114435
role of aspergillus and candida species in allergic bronchopulmonary mycoses. a comparative study.allergic bronchopulmonary aspergillosis (abpa) and allergic bronchopulmonary candidiasis (abpc) has been diagnosed in 20 and 13 cases respectively with one case in common, on the basis of laboratory and clinical findings. most of the abpa cases (60%) diagnosed had an early onset of respiratory symptoms, i.e. below the age of 30 years, while most of abpc cases (69%) had a late onset of respiratory symptoms, i.e. after the age of 30 years. the precipitin bands in abpa and abpc were r-type and h-ty ...1979118528
in vitro restoration of nitrate reductase: investigation of aspergillus nidulans and neurospora crassa nitrate reductase mutants.extracts of aspergillus nidulans wild type (bi-1) and the nitrate reductase mutant niad-17 were active in the in vitro restoration of nadph-dependent nitrate reductase when mixed with extracts of neurospora crassa, nit-1. among the a. nidulans cnx nitrate reductase mutants tested, only the molybdenum repair mutant, cnxe-14 grown in the presence of 10-minus 3 m na2 moo4 was active in the restoration assay. aspergillus extracts contained an inhibitor(s) which was measured by the decrease in nadph- ...1975123779
pyrimidine biosynthesis in aspergillus nidulans. isolation and characterisation of mutants resistant to fluoropyrimidines.mutants resistant to 5-fluorouracil, 5-fluorouridine and 5-fluorodeoxyuridine have been selected in aspergillus nidulans. growth tests combined with genetic analysis showed that mutations conferring resistance to fluoropyrimidines could occur in at least seven genes. three of these fule, fulf and fura were concerned with either the uptake of pyrimidines or their conversion to uridine monophosphate. the other four genes did not affect these functions. mutations in fula probably confer resistance ...1975127929
compartmentation and regulation of fungal metabolism: genetic approaches. 1975129029
atmospheric mutagens. i. sulfur oxides and nitrogen oxides. 1976134284
adenosine triphosphatase of aspergillus nidulans: effect of growth temperature. 1976140148
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
nitrate assimilation in fungi. 1978157059
mitochondrial atpase complex of aspergillus nidulans and the dicyclohexylcarbodiimide-binding protein.the dicyclohexylcarbodiimide-binding protein of aspergillus nidulans has been identified as the smallest subunit of the mitochondrial atpase complex, and has a molecular weight of approximately 8000. it is extractable from whole mitochondria and from the purified enzyme in neutral chloroform/methanol, contains 30% polar amino acids, and the n-terminal amino acid has been identified as tyrosine. using a double-labelling technique in the absence and presence of cycloheximide, followed by immunopre ...1979157278
adenosine triphosphatase of aspergillus nidulans: existence of isoenzymes of ca2+-atpase.ca2+-atpase activity increased five- to six fold when the cells were subjected to growth at 37 degrees c in protein hydrolysate-supplemented media as compared to that of the cells grown in minimal media. one major isoenzyme and one minor isoenzyme were present in minimal-medium-grown cells while two major isoenzymes were present in the cells grown in protein-supplemented media. when the cells were subjected to heat stress (43 degrees c), they exhibited significantly decreased activity as compare ...1979158522
short-term tests for carcinogens and mutagens. 1979159413
mechanism of action of monoketo-organomycin, cystaurimycin and their performic acid-oxidized modifications. ii. inhibition of mitochondrial atpase activity in aspergillus nidulans and identification of the performic acid-oxidized modifications-binding protein. 1979159889
regulation of mannitol-1-phosphate dehydrogenase in aspergillus nidulans. 1975163669
carbon catabolite repression in aspergillos nidulans. 1975168071
kinetics and morphology of glucose-limited cultures of moulds grown in a chemostat and on solid media.the affinity (ks value) of geotrichum candidum for glucose determined from chemostate cultures was ca. 1 mg/1. ks values for glucose was also estimated from the radial growth rates of colonies of g. candidum and neurospora crassa grown on media solidified with agar or silica gel. an assessment is made of the use of colony radial growth rate to determine substrate affinities. the length of apical and intercalary hyphal comparte ments, internode length and the diameter of leading hyphaat the margi ...1975168829
a mutant of aspergillus nidulans defective in nad-linked glutamate dehydrogenase.a mutation leading to partial loss of nad-linked ("catabolic') glutamate dehydrogenase does not affect the regulation of ammonium-repressible activities in aspergillus nidulans. this mutation has been used to show that nad-linked glutamate dehydrogenase does not normally participate in ammonium assimilation. a mutation leading to loss of nadp-linked ("anabolic') glutamate dehydrogenase has been used to show that nadp-linked glutamate dehydrogenase is not normally involved in glutamate catabolism ...1975172777
sexual differentiation in aspergillus nidulans: the requirement for manganese and the correlation between phosphoglucomutase and the synthesis of reserve material.aspergillus nidulans was completely devoid of fruit bodies when grown on manganese deficient cultures. this result was shown earlier to be due to a lack of alpha-1,3 glucan in the cell wall. several enzymes of carbon and nitrogen metabolism were investigated in an attempt to explain the absence of this reserve material. synthesis of glucose-6-phosphate dehydrogenase, phosphoglucoisomerase and aldolase, were not strongly affected by manganese deficiency. however, phosphoglucomutase showed only 60 ...1975173248
mutants of aspergillus nidulans lacking nicotinamide adenine dinucleotide-specific glutamate dehydrogenase.ten mutants of aspergillus nidulans lacking nicotinamide adenine dinucleotide-specific glutamate dehydrogenase (nad-gdh) have been isolated, and their mutations (gdhb1 through gdhb10) have been shown to lie in the gdhb gene. in addition, a temperature-sensitive gdhb mutant (gdhb11) has been isolated. a revertant (designated r-5) of the mutant gdhb1 bears an additional lesion in the gdhb gene and has altered nad-gdh activity with altered km values for ammonia or ammonium ions and for alpha-ketogl ...1976173707
formation in the dark, of virus-induced deoxyribonuclease activity in anacystis nidulans, an obligate anacystis nidulans, upon infection with cyanophage as-1, after a lag period of 1 h the level of deoxyribonuclease (dnase) activity increaded rapidly up to 15- to 20-fold in 4 to 5 h in the light. in contrast, the ribonuclease and phosphomonoesterase activities increased significantly only 4 to 5 h after infection, i.e. as late as 1 h prior to lysis. in complete darkness, the nuclease levels remained unaltered. however, when the infected cells were exposed to light for 1 or 2 h after infection ...1976177400
three genes determine the carboxin sensitivity of mitochondrial succinate oxidation in aspergillus nidulans. 1975178574
the effect of glucose and manganese on adenosine-3',5'-monophosphate levels during growth and differentiation of aspergillus nidulans.the role of cyclic adenosine monophosphate (camp) during growth and development of aspergillus nidulans was investigated. in normal cultures the highest amount of camp, expressed on a dry weight basis, was found after 24 h of growth when still more than 5% glucose was present in the medium. after depletion of the medium even a slight fall in camp was noted. glucose concentrations ranging from 0.5-12% resulted in a slight decrease in the amount of camp as measured after 24 h of growth. cultures w ...1976179489
effect of growth temperature on the cell constituents of aspergillus nidulans. 1977202564
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
the structural gene for nadp l-glutamate dehydrogenase in aspergillus nidulans.a total of 41 mutants lacking nadp l-glutamate dehydrogenase (nadp-gdh) activity have been studied. all the mutations were located at the gdha locus within 0-1% recombination of gdhai. two mutants, gdhai and gdha2, out of five examined, produced cross-reacting material which neutralized nadp-gdh anti-serum. the mutant gdha9 has altered km values for all five substrates: ammonium, alpha-ketoglutarate, l-glutamate, nadph and nadp. the mutant gdha20 had temperature-sensitive growth, abnormal ammoni ...1975234511
analysis of results of catheter tip cultures in open-heart surgery patients.a statistical analysis of 628 consecutive catheter tip cultures is presented. all were from patients undergoing open-heart surgery. the previously noted effects of early removal are shown to be significant. the possible effects of stasis, flushing, handling, and place of insertion are discussed. the unresolved significance of isolations of aerobic sporing bacilli is noted, and a decreasing incidence of postoperative infective endocarditis in the same group of patients is an encouraging sign.1975235801
the regulation of nitrate reductase in the fungus aspergillus nidulans. 1975241670
enzymology and genetic regulation of a cyclic nucleotide-binding phosphodiesterase-phosphomonoesterase from aspergillus nidulans.a cyclic nucleotide-binding phosphohydrolase that possesses both a phosphomonoesterase and a phosphodiesterase catalytic function has been partially purified from aspergillus nidulans. the enzyme hydrolyzes both p-nitrophenylphosphate and bis-(p-nitrophenyl)-phosphate. o'-nucleoside monophosphates are the best physiological phosphomonesterase substrates but 5'- and 2'-nucleoside monophosphates are also hydrolyzed. the enzyme catalyzes the hydrolysis of adenosine 5'-triphosphate, adenosine 5'-dip ...1975241743
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 and nitrate reductase (ec 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
polyamine stimulation of in vivo rates of macromolecular synthesis in a putrescine auxotroph of aspergillus nidulans. 1978340271
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
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
[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
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 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 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
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