PMID(sorted descending)
genetic and environmental modification of gene expression in the brla12 variegated position effect mutant of aspergillus nidulans. 19846378720
s-phase, g2, and nuclear division mutants of aspergillus nidulans.twenty-two temperature-sensitive cell cycle mutants of the fungus aspergillus nidulans, which block in interphase at restrictive temperature, were analyzed by the reciprocal shift method of jarvik and botstein (proc. nath acad. sci. u.s.a. 70:2046-2050, 1973) and hereford and hartwell (j. mol. biol. 84:445-461, 1974) to determine whether these mutations were blocked at the g1, s, or g2 phase of the cell cycle. we found five mutants to be blocked in s and nine to be blocked in g2. two of the g2 m ...19846376468
spontaneous duplications and transpositions of a large chromosome segment in aspergillus nidulans.spontaneous revertants of the leaky ade20 mutant of aspergillus nidulans were obtained as vigorous sectors emerging from stunted colonies on adenine-free medium. among the genetically heterogeneous sectors up to about 20% were recognized unequivocally as having an additional chromosome segment bearing ade20; two doses of this leaky allele permitted growth without added adenine. eleven spontaneous duplication strains of independent origin were analysed genetically. eight carried the duplicate seg ...19846374027
interactions of ribosomal antibiotics and informational suppressors of aspergillus nidulans.strains of aspergillus nidulans containing informational suppressors were grown on medium containing antibiotics known to affect protein synthesis at the ribosomal level. these strains reacted in the anticipated manner: presumed ribosomal suppressors suaa101, suaa105, suac109 and sua-115 were sensitive or even hypersensitive to aminoglycoside antibiotics, whereas presumed trna-like suppressors suab111, suad103 and d108 were only slightly sensitive or wild-type in response. hygromycin and paromom ...19846374026
evidence for two control genes regulating expression of the quinic acid utilization (qut) gene cluster in aspergillus nidulans.the first three steps in quinic acid degradation in aspergillus nidulans are catalysed by highly inducible enzymes encoded by a gene cluster regulated by an adjacent control region. analysis of two non-inducible mutants has been done in diploid strains, where quta8 is recessive and all three enzyme activities are fully induced in heterozygous quta8/quta+ diploids. in contrast, quta4/quta+ heterozygous diploids show semi-dominance of the mutant allele, giving markedly diminished growth on quinic ...19846374025
genotoxicity of the free-radical producers ccl4 and lipoperoxide in aspergillus nidulans.the false negative compounds, carbon tetrachloride and linoleic acid peroxide, induce somatic segregation in a. nidulans, but are negative or weak in inducing gene mutation in a haploid strain of the same organism. the other carcinogen tested, chcl3, was negative in both tests. a model involving free-radical formation is proposed to explain the results. finally, cysteamine, a free-radical scavenger, could partially counteract the genotoxicity of ccl4. the existence of carcinogens, predominantly ...19846371516
separation and characterization of pyrimidine deoxyribonucleoside 2'-hydroxylase and thymine 7-hydroxylase from aspergillus nidulans.partially purified preparations from aspergillus nidulans were shown to catalyze two alpha-ketoglutarate dependent dioxygenase reactions: the pyrimidine deoxyribonucleoside 2'-hydroxylase (ec and the thymine 7-hydroxylase (ec reactions. these reactions showed an absolute requirement for alpha-ketoglutarate and molecular oxygen and were stimulated by fe(ii), ascorbate and catalase. both reactions demonstrated a stoichiometry such that for each mole of substrate (deoxyribonuc ...19846370754
transformation by integration in aspergillus nidulans.dna-mediated genetic transformation of aspergillus nidulans has been achieved by incubating protoplasts from a strain of a. nidulans carrying a deletion in the acetamidase structural gene with dna of derivatives of plasmid pbr322 containing the cloned structural gene for acetamidase [hynes et al., mol. cell. biol. 3 (1983) 1430-1439; p3sr2] in the presence of polyethylene glycol and cacl2. the highest frequency obtained was 25 transformants per microgram of dna. no enhancement of the transformat ...19836368319
purification and properties of purine hydroxylase ii from aspergillus nidulans.purine hydroxylase ii from aspergillus nidulans has been purified to near homogeneity. the enzyme has a pi of 5.7, a molecular weight of 300,000, and two subunits with molecular weight of 153,000 each. the enzyme contains 2 fad, 2 molybdenum atoms, and 4 (2 fe-2s) iron-sulfur centers per molecule and exhibits broad specificity for reducing and oxidizing substrates. among the more notable characteristics are the ability to oxidize hypoxanthine and nicotinic acid but not xanthine and virtually com ...19846367661
a chromosome assay method for the detection of heterokaryon incompatibility (het) genes operating between members of different heterokaryon compatibility (h-c) groups in aspergillus nidulans.protoplast fusion has made possible the isolation of a diploid strain from haploid parents belonging to heterokaryon compatibility (h-c) groups q and gl of aspergillus nidulans. this diploid was not fully heterokaryon compatibility tests conducted between selected pairs of parasexually derived progeny strains facilitated a chromosome assay method for the detection of heterokaryon incompatibility (het) genes. despite the lack of segregation for the linkage group vi marker, it proved possible to l ...19836366117
the location and analysis of two heterokaryon incompatibility (het) loci in strains of aspergillus nidulans.the heterokaryon incompatibility system in aspergillus nidulans has been investigated by parasexual methods. the use of complementary auxotrophs with a repeated serial transfer method or with a protoplast fusion technique has enabled heterokaryons and diploid strains to be recovered from heterokaryon incompatible combinations of strains. the effects of allelic interaction at heterokaryon incompatibility (het) loci on the morphologies of the heterokaryon and diploid colonies isolated are describe ...19836366116
induced mutation developing delta 9-desaturase defective unsaturated fatty acid requiring mutants of aspergillus nidulans imi 72731. 19836365749
disruptive effects of ethyl alcohol on mitotic chromosome segregation in diploid and haploid strains of aspergillus identify, with certainty, the primary genotoxic effects of ethanol, condidia from diploid strains of aspergillus nidulans were treated during early germination with ethyl alcohol, and all the resulting segregants from large samples were analysed in detail. results were identical whether technical grade (95%), or highly purified 'absolute', alcohol was diluted to obtain the effective low levels of ethanol (3-6%). this makes it unlikely that trace contaminants, rather than ethanol itself, cause ...19846363912
bifunctionality and polarized infidelity at the hisb locus of aspergillus nidulans.the histidine (hisb) locus of aspergillus nidulans is unusual in two ways. firstly, it is bifunctional; besides coding for imidazole glycerol phosphate (igp) dehydrase, it is required for the production of ascospores (fertility). it appears, therefore, to be partly homologous to the hisb locus of salmonella typhimurium, which codes for igp dehydrase and histidinol phosphate phosphatase. secondly, during meiosis it is often inaccurately transmitted to the progeny (infidelity). this phenomenon may ...19846363882
developmental defects resulting from arginine auxotrophy in aspergillus nidulans.a mutant of aspergillus nidulans, isolated for inability to form asexual spores (conidia) on complete medium, was found to regain the ability to conidiate if the medium was supplemented with arginine. on minimal medium the mutant required arginine for growth but at a much lower concentration than that required for conidiation. this mutant, designated argb12, thus defines a phase-critical gene, i.e. a gene whose function is in greater demand for development than for growth. in addition to its aco ...19836363619
aspects of genetic interaction in hybrids of aspergillus nidulans and aspergillus rugulosus obtained by protoplast fusion.hybrids were produced by protoplast fusion between strains of aspergillus rugulosus and mitotic master strains of aspergillus nidulans with a genetic marker on each linkage group. analysis of segregants induced by growth on benomyl revealed recombination between every pair of unlinked markers. parental combinations of markers were often recovered at significantly higher frequencies than expected. this aberrant segregation was not correlated with any particular pair of linkage-groups and was attr ...19836363618
cloning and characterization of the ornithine carbamoyltransferase gene from aspergillus aspergillus nidulans dna fragment composed of two adjacent sali subfragments (1.8 and 0.85 kb) that carries an argb gene complementing the yeast arg3 mutation has been isolated from two different gene libraries. hybridization results and immunological tests indicate that the cloned fragment contains the a. nidulans structural gene coding for ornithine carbamoyltransferase (otcase). using the cloned gene as a probe, the specific mrna was identified. the level of this rna observed in a. nidulan ...19836363209
the intron of the mitochondrial 21s rrna gene: distribution in different yeast species and sequence comparison between kluyveromyces thermotolerans and saccharomyces cerevisiae.we have screened numerous different yeast species for the presence of sequences homologous to the intron of the mitochondrial 21s rrna gene of saccharomyces cerevisiae (intron r1) and found them in all kluyveromyces species, some of the saccharomyces species and none of the other yeasts tested. we have determined the nucleotide sequence of the r1-intron in k. thermotolerans and compared it with that of s. cerevisiae. the two introns are inserted at the same position within the 21s rrna gene. the ...19836361491
the genetic location of three mutations impairing penicillin production in aspergillus nidulans.three mutations impairing penicillin production in aspergillus nidulans, npeb, npec and nped, have been located on linkage groups iii, iv and ii, respectively, and positioned relative to other loci on these chromosomes.19836361214
genotoxic activity of plant growth-regulating hormones in aspergillus nidulans.three plant growth-regulating hormones, indole-3-acetic acid (iaa), indole-3-butyric acid (iba), and kinetin (6-furfuryl-aminopurine), were tested for their genetic activity in aspergillus nidulans in a plate test. the first two hormones were found to greatly increase somatic segregation in the fungus whereas kinetin was not effective. several concentrations of the plant hormones were used and it was found that increasing concentrations of iaa and iba increased mitotic segregation of the fungus ...19836357521
a polyamine-sensitive mutant of aspergillus nidulans.a mutation designated spsa1 has been induced in the putrescine (pua2) auxotroph of aspergillus nidulans which enables this mutant to grow on low concentrations of spermidine in place of putrescine. in addition, the spsa1 mutant, irrespective of putrescine requirement, is abnormally sensitive to high concentrations of spermidine, spermine or the polyamine analogue methylglyoxal bis(guanylhydrazone). when spsa1 strains are grown on medium containing spermidine, uptake of the polyamine continues at ...19836355384
purification and properties of two neutral proteinases from aspergillus nidulans.two proteinases have been purified from mycelial extracts of aspergillus nidulans. both enzymes have ph optima between 6.5 and 7.5 and are inhibited by phenylmethane sulphonyl fluoride and by di-isopropyl fluorophosphate. the molecular weights and isoelectric points of proteinase i and proteinase ii are 30 900 and 30 000, and 4.6 and 4.3, respectively. both enzymes have a similar range of substrate specificities. the principal differences in their properties are that proteinase i is sensitive to ...19836355383
isolation of genomic clones containing the amds gene of aspergillus nidulans and their use in the analysis of structural and regulatory mutations.previous analysis of the amds gene of aspergillus nidulans has identified multiple regulatory circuits mediated by trans-acting regulatory genes, cis-acting mutations have been identified and shown to specifically affect individual regulatory circuits. fine-structure genetic mapping of the amds regions showed that these cis-acting mutations occur in a complex controlling region adjacent to the amds structural gene. the amds gene was cloned by differential hybridization, using cdna probes derived ...19836353203
kinetics of the nuclear division cycle of aspergillus nidulans.we have analyzed the cell cycle kinetics of aspergillus nidulans by using the dna synthesis inhibitor hydroxyurea (hu) and a temperature-sensitive cell cycle mutant nimt that blocks in g2. hu rapidly inhibits dna synthesis (s), and as a consequence progression beyond s to mitosis (m) is blocked. upon removal of hu the inhibition is rapidly reversible. conidia (asexual spores) of nimt were germinated at restrictive temperature to synchronize germlings in g2 and then downshifted to permissive temp ...19836352675
mitochondrial transfer rna genes from fungi (aspergillus nidulans) and plants (lupinus luteus) are transcribed in xenopus laevis oocyte nuclei.three plasmids containing aspergillus nidulans mitochondrial transfer rna genes were microinjected into the nucleus of xenopus laevis oocytes. plasmids that contained a single trnacys gene or two trna genes (arg and asn) yielded trna-sized transcripts. plasmids containing cloned lupinus mitochondrial trna genes were also transcribed and processed in x. laevis nuclei.19836350603
nitrate uptake in aspergillus nidulans and involvement of the third gene of the nitrate assimilation gene aspergillus nidulans, chlorate strongly inhibited net nitrate uptake, a process separate and distinct from, but dependent upon, the nitrate reductase reaction. uptake was inhibited by uncouplers, indicating that a proton gradient across the plasma membrane is required. cyanide, azide, and n-ethylmaleimide were also potent inhibitors of uptake, but these compounds also inhibited nitrate reductase. the net uptake kinetics were problematic, presumably due to the presence of more than one uptake ...19836350263
properties of deoxyribonuclease 4 from aspergillus nidulans.deoxyribonuclease 4 from aspergillus nidulans was purified to over 70% homogeneity. it contains a polypeptide of mr about 30000, and behaves as a dimer, but with some evidence of dissociation on gel filtration and ultracentrifugation. the ph optimum is 7-9. activity is supported by metal ions in the order (mn2+ + ca2+) greater than mn2+ approximately equal to (mg2+ + ca2+) much greater than mg2+. mn2+ is optimal at 10-20 mm. dnaase 4 strongly prefers native dna, for which the km is about 0.5 mm, ...19836349692
mutagenicity screening with fungal systems.several fungal species have been used for mutagenicity screening: aspergillus nidulans, saccharomyces cerevisiae, and neurospora crassa. the eukaryotic nature of these organisms with typical chromosomes in a nucleus and their mitotic and meiotic mode of nuclear division have been the basis for the development of test systems that cover the full spectrum of genetic changes typical for eukaryotes. it is possible to detect simple point mutations and also grosser structural chromosomal alterations. ...19836349475
nitrite toxicity in aspergillus nidulans: a new locus in a proa1 pabaa6 ya2 strain. 19836345269
the sub-cellular localisation of pyruvate carboxylase and of some other enzymes in aspergillus nidulans.the sub-cellular localisation of enzymes has been defined by latency analysis, and fractionation by differential centrifugation, in cell-free extracts prepared from the mycelium of aspergillus nidulans by growth in the presence of 2-deoxyglucose followed by treatment with a mixture of beta-glucuronidase, sulphatase and beta-glucanase and exposure to n2 cavitation at 5.2 pma. in such extracts pyruvate carboxylase and nad-dependent and nadp-dependent glutamate dehydrogenases are exclusively locali ...19836345155
short-cycle conidiation in aspergillus nidulans influence of glucose concentration and acetate or citrate supply.this paper considers the effects of the reduction of the glucose concentration in the medium or of its substitution by intermediates closely related to the tca cycle, namely acetate and citrate, on the balance between conidiation and mycelial growth in aspergillus nidulans. it is shown that in conditions of extreme depletion of glucose in the medium, or in the presence of citrate as the only source of organic carbon, the reduction of mycelial growth proceeds to such as extent that conidiophores ...19836341779
conditionally lethal tubulin mutations of aspergillus nidulans.conditionally lethal tubulin mutants are becoming an important tool for studying microtubule structure and function. in the filamentous fungus aspergillus nidulans it has been possible to isolate heat-sensitive beta-tubulin mutations by isolating mutants resistant to the anti-microtubule agent benomyl and screening these mutants for heat sensitivity. it has also been possible to isolate alpha-tubulin mutations, new beta-tubulin mutations and mutations in other genes whose products are likely to ...19836341617
laccase localized in hulle cells and cleistothecial primordia of aspergillus nidulans.several species of the genus aspergillus form sexual spores within minute (approximately 0.2 mm) spherical shells (cleisthothecia) which are woven from specialized hyphae. aspergillus nidulans cleistothecia are uniquely characterized by their dark red coloration and an envelope of thick-walled globose cells (hulle cells). by use of a new chromogenic substrate, we have shown that the constitutent hyphae of young cleistothecia and the hulle cells which surround the cleistothecia of a. nidulans exh ...19836341366
diagnosis of nonsense mutations in aspergillus nidulans.three genotypically suppressible alleles, a1x4, alca125, and niad500, are phenotypically suppressed by aminoglycoside antibiotics. unsuppressible alleles at these loci are unaffected as are known missense mutations at the ya and gdha loci. this is consistent with the premise that the suppressible mutations are nonsense and that this highly-allele-specific phenotypic suppression can be used to distinguish nonsense from missense mutations of aspergillus nidulans. paromomycin and tobramycin are rec ...19836340750
[lethal and mutagenic action of solar radiation on model microbiological test systems].lethal, mutagenic and recombonogenic action of the solar radiation on the model microorganisms--phage t4, bacteria escherichia coli and ascomycet aspergillus nidulans--has been studied. a considerable lethal effect of the solar radiation on phage t4 and e. coli was found. an increasing of mutation frequency in e. coli and a. nidulans by sunlight was also revealed. recombinogenic action of solar radiation has been demonstrated in the experiments with diploid a. nidulans strains. it was shown that ...19836340743
dna duplication has resulted in transfer of an amino-terminal peptide between two mitochondrial proteins.the mitochondrial genome of the ascomycete aspergillus nidulans possesses at least nine unidentified reading frames (urfs). two of these are particularly interesting in that the amino acid sequences of the derived translation products are very similar in the n-terminal regions. the first 36 residues of the urfx gene product are repeated at the start of a second reading frame, urfa3, with only six mismatches. despite this similarity in their amino-termini, the latter parts of urfx and urfa3 are c ...19836339955
detection of a proteinase inhibitor in aspergillus nidulans.the activity of proteinases in mycelial extracts of aspergillus nidulans increased during storage. the rate of activation increased with temperature. three separate proteinase activities, differing in their electrophoretic mobilities on polyacrylamide gels, were readily detected at ph 6.5. inhibitory activity, effective against all three proteinase activities, was also detected in fractions prepared from fresh mycelial extracts. the inhibitory factor(s) were heat-stable and non-dialysable. the i ...19836339674
a mutation in aspergillus nidulans that blocks the transition from interphase to order to develop a method for obtaining mitotic synchrony in aspergillus nidulans, we have characterized previously isolated heat-sensitive nim mutations that block the nuclear division cycle in interphase at restrictive temperature. after 3.5 h at restrictive temperature the mitotic index of a strain carrying one of these mutations, nima5, was 0, but when this strain was subsequently shifted from restrictive to permissive temperature the mitotic index increased rapidly, reaching a maximum of ...19836339527
cloning of nitrate reductase genes from the cyanobacterium anacystis nidulans.anacystis nidulans, a non-nitrogen-fixing cyanobacterium, can fulfill its nitrogen requirement by the assimilation of nitrate. the first step in the pathway, the reduction of nitrate to nitrite, is catalyzed by the molybdo-protein nitrate reductase. in this study, newly developed techniques for gene cloning in a. nidulans r2 were used for the isolation of two genes involved in nitrate reduction. one gene was cloned by complementation of the corresponding mutant; the other gene was picked up from ...19846330039
identification of the probable coding region for exon 2 of cytochrome oxidase polypeptide i from aspergillus nidulans mitochondrion.hypothetical protein urfe of aspergillus nidulans mitochondrion is homologous with the amino end of cytochrome oxidase (ec polypeptide i. unidentified reading frame urfe does not contain a suitable initiation codon and codes for a protein with a length of only 91 residues, corresponding to about 20% of cytochrome oxidase polypeptide i. it is proposed that this region codes for the second exon of the cox 1 gene of aspergillus mitochondrion. possible candidates for the 2- to 3-residue ami ...19846324773
transformation of aspergillus nidulans by using a trpc plasmid.we constructed a chimeric plasmid carrying a complete copy of the trifunctional trpc gene from the ascomycete fungus aspergillus nidulans. this plasmid, designated phy201, replicates in escherichia coli, where it confers resistance to ampicillin and chloramphenicol and complements trpc mutants lacking phosphoribosylanthranilate isomerase activity. we used phy201 to transform an a. nidulans trpc- strain to trpc+ at frequencies of greater than 20 stable transformants per microgram of dna. southern ...19846324193
developmental regulation of the aspergillus nidulans trpc gene.we have cloned the trifunctional trpc gene from aspergillus nidulans by hybrid phage lambda complementation of an escherichia coli trpc mutant lacking phosphoribosylanthranilate isomerase activity. four different phages sharing a 4.3-kilobase region were obtained. plasmid subclones containing this region also complemented the e. coli trpc mutant. we determined that a 1.8-kilobase dna fragment was minimally required for complementation. the fragment hybridized with two poly(a)+ rnas, 3.0 and 3.2 ...19836324178
amino acid sequence of a new mitochondrially synthesized proteolipid of the atp synthase of saccharomyces cerevisiae.the purification and the amino acid sequence of a proteolipid translated on ribosomes in yeast mitochondria is reported. this protein, which is a subunit of the atp synthase, was purified by extraction with chloroform/methanol (2/1) and subsequent chromatography on phosphocellulose and reverse phase h.p.l.c. a mol. wt. of 5500 was estimated by chromatography on bio-gel p-30 in 80% formic acid. the complete amino acid sequence of this protein was determined by automated solid phase edman degradat ...19846323165
optical and electron paramagnetic resonance spectroscopic studies on purine hydroxylase ii from aspergillus nidulans.purine hydroxylase ii from aspergillus nidulans contains a molybdenum cofactor very similar to that found in a number of other molybdenum-containing hydroxylases. (a. nidulans contains two purine hydroxylases, i and ii, related to each other by possession of a common cofactor and overlapping substrate specificity.) addition of reducing substrates effects bleaching of the visible absorption spectrum of the enzyme, the decrease in absorbance at 450 nm being linearly proportional to that at 550 nm. ...19846322698
sequence homology and structural similarity between cytochrome b of mitochondrial complex iii and the chloroplast b6-f complex: position of the cytochrome b hemes in the membrane.the amino acid sequences of cytochrome b of complex iii from five different mitochondrial sources (human, bovine, mouse, yeast, and aspergillus nidulans) and the chloroplast cytochrome b6 from spinach show a high degree of homology. calculation of the distribution of hydrophobic residues with a "hydropathy" function that is conserved in this family of proteins implies that the membrane-folding pattern of the 42-kilodalton (kda) mitochondrial cytochromes involves 8-9 membrane-spanning domains. th ...19846322162
distinction between cofactor-dependent and -independent phosphoglycerate mutases by chromatography on cibacron blue-sepharose.the binding of phosphoglycerate mutases from a variety of sources to cibacron blue-sepharose has been examined. those enzymes which are dependent on 2,3-bisphosphoglycerate (bpg) for activity bind to the immobilized dye and can be eluted by bpg. those enzymes which are independent of bpg do not bind to the immobilized dye. the possible structural significance of this distinction is discussed.19836315103
a host-vector system for gene cloning in the cyanobacterium anacystis nidulans r2.we describe the construction of a series of vectors suitable for gene cloning in the cyanobacterium anacystis nidulans r2. from the indigenous plasmid puh24, derivatives were constructed with streptomycin as the selective marker; one of these plasmids was used to construct puc303, a shuttle vector capable of replication in a. nidulans r2 as well as in escherichia coli k12. it has two markers, streptomycin and chloramphenicol resistance, and three unique restriction sites. instability of recombin ...19836314409
shuttle cloning vectors for the cyanobacterium anacystis nidulans.hybrid plasmids capable of acting as shuttle cloning vectors in escherichia coli and the cyanobacterium anacystis nidulans r2 were constructed by in vitro ligation. dna from the small endogenous plasmid of a. nidulans was combined with two e. coli vectors, pbr325 and pdpl13, to create vectors containing either two selectable antibiotic resistance markers or a single marker linked to a flexible multisite polylinker. nonessential dna was deleted from the polylinker containing plasmid pplan b2 to p ...19836311795
a hybrid plasmid is a stable cloning vector for the cyanobacterium anacystis nidulans r2.anacystis nidulans r2 is a highly transformable strain which is suitable as a recipient for molecular cloning in cyanobacteria. in an effort to produce an appropriate cloning vector, we constructed a hybrid plasmid molecule, psg111, which contained pbr328 from escherichia coli and the native puh24 plasmid of a. nidulans. psg111 replicated in and conferred ampicillin and chloramphenicol resistance to both hosts. it contained unique sites for the restriction enzymes ecori, sali, sphi, and xhoi, wh ...19836309751
a new hybrid plasmid capable of transforming escherichia coli and anacystis nidulans.we have constructed a hybrid plasmid, pdf30, by combining the 8-kb pdf3 plasmid derived from the cyanobacterium anacystis nidulans 6311 with the escherichia coli vector pbr325. pdf30 transforms, replicates and confers chloramphenicol resistance (cmr) and ampicillin resistance (apr) on both a. nidulans and e. coli. the level of resistance to ampicillin in a. nidulans transformants, although low, is above background resistance and an apr activity was demonstrated in cell-free extracts of a. nidula ...19836307827
a physical map of the ribosomal dna repeat unit of aspergillus nidulans.the ribosomal dna repeat unit of aspergillus nidulans has been cloned in pbr322 and a restriction map constructed. the genes coding for the 17s, 5.8s and 25s rrnas are found in blocks separated by a 1.7 kb spacer region, with the 5.8s rna gene lying between the genes for the two larger rnas. the total length of the repeat unit is 7.7 kb. the 5s rrna is not present in the repeat unit.19826299883
a new approach for molecular cloning in cyanobacteria: cloning of an anacystis nidulans met gene using a tn901-induced mutant.a new strategy for molecular cloning in the cyanobacterium anacystis nidulans r-2 is described. this strategy involved the use of a transposon and was developed for the cloning of a gene encoding methionine biosynthesis. a met::tn901 mutant was isolated. chromosomal dna fragments were cloned in the escherichia coli plasmid vector pacyc184. a recombinant plasmid carrying the inactivated met::tn901 gene was selected after transformation to e. coli. the cloned met::tn901 dna fragment was used as a ...19826298064
genetic approaches to the analysis of microbial development. 19826297378
proton pump coupled to cytochrome c oxidase in the cyanobacterium anacystis nidulans.intact spheroplasts of the cyanobacterium anacystis nidulans were found to oxidize various exogenous c-type cytochromes with concomitant proton extrusion. in the coupled state, h+/e stoichiometries close to 1 were measured, regardless of absolute reaction rates. it is concluded that the proton translocation observed is an intrinsic property of the cytoplasmic membrane-bound cytochrome c oxidase of a. nidulans.19836294060
nucleotide sequence of aspergillus nidulans mitochondrial genes coding for atpase subunit 6, cytochrome oxidase subunit 3, seven unidentified proteins, four trnas and l-rrna.the complete nucleotide sequence of a 14 kb segment of a. nidulans mtdna reveals a rather compact organization of genes transcribed from the same strand and coding for two functionally known proteins, seven unidentified polypeptides (urfs), 24 trnas and two rrnas. one of the urfs is located in the intron of the l-rrna gene and codes for a basic protein of 410 residues. the other urfs are in spacer regions and code for hydrophobic proteins. urfa is homologous to human urf4, and urfb produces a po ...19826290989
cloning and expression in escherichia coli k-12 of the biosynthetic dehydroquinase function of the arom cluster gene from the eucaryote, aspergillus nidulans.a 1.35 md dna hindiii fragment containing part of the arom gene cluster or cluster gene of aspergillus nidulans encoding biosynthetic dehydroquinase (5-dehydroquinate hydrolyase) has been cloned in plasmid pbr322 on the basis of functional expression in escherichia coli. the fungal fragment on pbr322, designated phk29, complements a corresponding e. coli dehydroquinase structural gene (arod) mutation. phk29 contains one bamhi, hpaii, psti, smai, xhoi and surprisingly, one hindiii site since phk2 ...19826287167
nucleotide sequence of a region of the mitochondrial genome of aspergillus nidulans including the gene for atpase subunit 6.a 1500 bp fragment of the aspergillus nidulans mitochondrial genome contains genes for arginine and asparagine trnas, an unassigned reading frame, and the structural gene for atpase subunit 6. the trna genes possess 66% nucleotide homology and possibly originated by a relatively recent duplication event. the unassigned reading frame displays a low level of homology with the human urf a6l. the predicted amino acid sequence of the a-nidulans atpase subunit 6 gene is 40% homologous to the yeast pol ...19826285306
organization of the ribosomal rna gene cluster in aspergillus nidulans.dna coding for ribosomal rna in aspergillus nidulans was found to consist of a unit 7.8 kb in size which is tandemly repeated in the genome and codes for 5.8s, 18s and 26s rrna. the repeat unit has been cloned, and its restriction map and the location of the individual rrna coding sequences within the unit have been established.19826282710
restriction enzyme analysis of mitochondrial dna of members of the genus aspergillus as an aid in taxonomy.restriction endonuclease patterns of mitochondrial dna from seven species of the genus aspergillus (a. nidulans, a. wentii, a. awamori, a. niger, a. oryzae, a. tamarii and a. echinulatus) have been compared in order to test the phylogenetic relationships between these species. the fraction of restriction fragments common between all pairs of species from this set ranged from 0 to 1. the use of this approach for the taxonomy of the genus aspergillus is discussed. the postulated phylogenetic relat ...19826281364
construction of a hybrid plasmid capable of replication in the bacterium escherichia coli and the cyanobacterium anacystis nidulans.a hybrid plasmid was constructed between the 5.3-megadalton plasmid (puh24) of anacystis nidulans r2 and the escherichia coli plasmid pbr322. this was accomplished by adding a transposon to pbr322 and transforming this dna into a. nidulans. one resultant hybrid, pls103, had a molecular weight of 6.8 x 10(6), replicated in both organisms, had unique sites for two restriction endonucleases, conferred ampicillin resistance on both organisms, and could be used as a cloning vector in a. nidulans.19826277870
vectors for cloning in cyanobacteria: construction and characterization of two recombinant plasmids capable of transformation of escherichia coli k12 and anacystis nidulans r2.two plasmids were constructed consisting of the e. coli vector pacyc184 and the cyanobacterial plasmid puc1. these recombinants, designated puc104 and puc105, can be transformed to e. coli k12 as well as to the cyanobacterium anacystis nidulans r2 and in both hosts they express their antibiotic markers. puc104 and puc105 differ with respect to the location and the orientation of the pacyc184 segment in puc1. puc104 was found to be stable under all circumstances. transformation of puc105 to a. ni ...19816276694
nucleotide sequence of the aspergillus nidulans mitochondrial gene coding for the small ribosomal subunit rna: homology to e. coli 16s rrna.the complete primary structure of the 1437 bp gene coding for mitochondrial 15s rrna and its flanking regions was determined by maxam-gilbert sequencing of cloned hindiii fragment h3 of a. nidulans mtdna. the gene product reveals significant homology (59%) to e. coli 16s rrna, and the potential secondary structures of both rrna molecules are very similar, except that the hairpin structures 7, 8 and 30 of the brimacombe 16s rrna model are deleted, and that two sequences of 8 and 31 nucleotides ar ...19816273804
the cloning of aspergillus nidulans mitochondrial dna in escherichia coli on plasmid pbr322. 19816270505
nuclear and mitochondrial suppression of a mitochondrially inherited cold-sensitive mutation in aspergillus nidulans.partial suppressors of a mitochondrially inherited mutation, [cs-67], conferring cold-sensitivity at 20 degrees c were identified. these mapped at one mitochondrial and four unlinked nuclear loci. most suppressors partially restored the cytochrome aa3 deficiency of the cold-sensitive strain at 20 degrees c. strains carrying two or more suppressors and [cs-67] showed considerably impaired growth. this effect was temperature-dependent, being more severe at 37 degrees c, and was not expressed in th ...19806262432
mitochondrial heterogeneity in aspergillus nidulans: in vivo protein biosynthetic activities of the mitochondrial populations.two mitochondrial populations with cytochrome c oxidase activity, and densities of 1.07 and 1.08 g/ml have been separated by means of a dextran-sucrose gradient. the highest enzymatic specific activity appeared in the 1.07 g/ml band. the mitochondria assayed by their in vivo cycloheximide resistant leucine incorporation appeared at the 1.08 g/ml density band of the gradient. some amount of activity of cytochrome c oxidase, and leucine incorporation appeared at the bottom of the gradient. the cyt ...19806261314
conservation and rearrangement of mitochondrial structural gene sequences.mitochondria contain the simplest dna molecules that are present in eukaryotes. mitochondrial dna (mtdna) is easily purified, and is an important model system for studying eukaryote gene structure and basic molecular processes. the protein sequences of mitochondrial gene products have been shown to be conserved from yeast to man, and there are definite similarities at the dna sequence level. in contrast, the overall organization of the mitochondrial genome is drastically different in these organ ...19806253835
mitochondrial heterogeneity in aspergillus nidulans: evidence of in vivo transformation among different mitochondrial populations.the distribution of mitochondria from aspergillus nidulans on a dextran-sucrose gradient resulted in the fractionation of three bands. the lightest band presented the highest respiratory and cytochrome c oxidase activities and was also the most active in the incorporation of tritiated glycerol. pulse-chase experiments with 3h-glycerol suggested that mitochondria from the light band was transformed to denser organelles as the organism grew.19806248928
introduction of transposon tn901 into a plasmid of anacystis nidulans: preparation for cloning in cyanobacteria.we have used the tem beta-lactamase transposon tn901, located on escherichia coli plasmid pri46, to introduce in vivo a genetic marker into plasmid puh24, present in the cyanobacterial strain anacystis nidulans r-2. restriction enzyme analysis and heteroduplex studies of the 8.3 x 10(6)-dalton plasmids pch1-pch5, present in the ampicillin-resistant a. nidulans r-2 colonies obtained after transformation with pri46, demonstrated that these plasmids consist of the complete sequence of tn901 inserte ...19806246495
physical map of aspergillus nidulans mitochondrial genes coding for ribosomal rna: an intervening sequence in the large rrna cistron.a detailed map of the 32 kb mitochondrial genome of aspergillus nidulans has been obtained by locating the cleavage sites for restriction endonucleases pst i, bam h i, hha i, pvu ii, hpa ii and hae iii relative to the previously determined sites for eco r i, hind ii and hind iii. the genes for the small and large ribosomal subunit rnas were mapped by gel transfer hybridization of in vitro labelled rrna to restriction fragments of mitochondrial dna and its cloned eco r i fragment e3, and by elect ...19806246396
cellular and extracellular siderophores of aspergillus nidulans and penicillium chrysogenum.aspergillus nidulans and penicillium chrysogenum produce specific cellular siderophores in addition to the well-known siderophores of the culture medium. since this was found previously in neurospora crassa, it is probably generally true for filamentous ascomycetes. the cellular siderophore of a. nidulans is ferricrocin; that of p. chrysogenum is ferrichrome. a. nidulans also contains triacetylfusigen, a siderophore without apparent biological activity. conidia of both species lose siderophores ...19816242827
genetic studies in micro-organisms producing beta-lactam antibiotics. 19846237946
cytochrome b gene of neurospora crassa mitochondria. partial sequence and location of introns at sites different from those in saccharomyces cerevisiae and aspergillus nidulans.we have sequenced a 2614-base pair fragment of the neurospora crassa mitochondrial dna which contains part of the structural gene for apocytochrome b. this gene is split by at least two introns. the sequence reported here begins within one intron, extends through the next exon, another intron 1276 base pairs long, and the last exon which encodes the cooh terminus of cytochrome b. within the 254 amino acids encoded by the two exons, there is a high degree of sequence conservation, 81%, with cytoc ...19846231283
transformation of aspergillus nidulans by the orotidine-5'-phosphate decarboxylase gene of neurospora crassa.relief of an auxotrophic requirement for uridine in aspergillus nidulans strain g191 has been achieved by transformation with a segment of neurospora crassa dna containing the corresponding gene coding for orotidine-5'-phosphate decarboxylase. the mitotic stability of such transformants suggests that the dna has integrated into the genome. southern hybridisation analysis of dna isolated from transformants revealed the presence of pbr322 sequences which have integrated into the host genome along ...19836220717
cell wall degradation in the autolysis of filamentous fungi.a systematic study on autolysis of the cell walls of fungi has been made on neurospora crassa, botrytis cinerea, polystictus versicolor, aspergillus nidulans, schizophyllum commune, aspergillus niger, and mucor mucedo. during autolysis each fungus produces the necessary lytic enzymes for its autodegradation. from autolyzed cultures of each fungus enzymatic precipitates were obtained. the degree of lysis of the cell walls, obtained from non-autolyzed mycelia, was studied by incubating these cell ...19826219290
intron within the large rrna gene of n. crassa mitochondria: a long open reading frame and a consensus sequence possibly important in splicing.we describe the sequence of the 2295 nucleotide long intron and 245 nucleotides of the flanking exon sequences within the large (24s) rrna gene of neurospora crassa mitochondria. the intron contains a long open reading frame, which could correspond to ribosomal protein s5. comparison with the corresponding intron of the large rrna gene of yeast mitochondria reveals a single highly homologous 57 nucleotide long sequence, including the sequence (formula; see text), which is present in virtually al ...19826218884
different biosynthetic pathways of the pyrimidine moiety of thiamin in procaryotes and eucaryotes.[14c]formate is incorporated into the c-2 of the pyrimidine moiety of thiamin by escherichia coli and salmonella typhimurium. in saccharomyces cerevisiae, it is incorporated into c-4. radioactive carbons of [1-14c]glycine and [2-14c]glycine are incorporated by s. typhimurium into the c-4 and c-6 of the pyrimidine, respectively, but not by s. cerevisiae. these facts suggest that procaryotes and eucaryotes have different biosynthetic pathways for pyrimidine. in this study, the procaryotes tested i ...19836218832
international commission for protection against environmental mutagens and carcinogens. committee 2 final report. mutagenesis testing as an approach to carcinogenesis. 19826214712
aspergillus contains multiple tubulin genes.previous work with benomyl-resistant mutants of aspergillus nidulans has demonstrated that the bena locus is a structural gene for beta-tubulin. two of the bena mutants, bena22 and bena85, show altered electrophoretic mobilities on two-dimensional gels for two beta-tubulins (designated beta 1 and beta 2). these shifts of the beta 1- and beta 2-tubulins uncover a spot in the region where wild-type beta-tubulins migrate that is occluded on gels of wild-type extracts by the beta 1- and beta 2-tubul ...19846210290
active rna: rna enzymes in rna splicing and processing. 19846210116
specificity of antigens from pathogenic aspergillus species. ii. studies with line immunoelectrophoresis.somatic (mycelial) and metabolic (culture filtrate) antigens of aspergillus flavus, a. fumigatus, a. nidulans, a. niger and a. terreus were compared by line immunoelectrophoresis with sera from patients with allergic bronchopulmonary aspergillosis (abpa) or aspergilloma, or from immunized animals. number of lines observed when tested with human sera were similar for somatic and metabolic preparations of a. fumigatus, but up to 33 lines were present when both types of antigens were tested simulta ...19846209814
polyamines. 19846206782
cloning and mapping of fourteen different dna fragments containing aspergillus nidulans 5s rrna genes.fourteen different plasmids hybridizing to aspergillus nidulans 5s rrna were isolated from a gene bank obtained after cloning sau3a partial digests of a. nidulans dna in a yeast--escherichia coli vector, pbb29. the restriction maps of these plasmids were determined. the size of the cloned fragments was 2.7-9.5 kb, 12 of the plasmids were found to code for single 5s rrna genes and 2 coded for 2 genes. no similarity of the sequences surrounding the 5s rrna genes was found by restriction mapping.19846205550
cloning of aspergillus nidulans ribosomal dna in shotgun experiments using the ek2 vector lambda gtwest.t5-622.ecori fragments of aspergillus nidulans dna were cloned in a shotgun type experiment using the ek2 vector lambda gtwest.t5-622. in situ plaque hybridization was used to screen for hybrid phage particles containing sequences coding for ribosomal rna. four clones selected from the whole gene bank were characterized further. two of them contain sequences homologous to a 3.6 kb fragment of a. nidulans rdna.19836198874
high-frequency conversion to a "fluffy" developmental phenotype in aspergillus spp. by 5-azacytidine treatment: evidence for involvement of a single nuclear gene.transient exposure of mycelia from aspergillus niger and aspergillus nidulans to the cytidine analog 5-azacytidine, leading to no more than 0.3 to 0.5% substitution for cytosine by 5-azacytosine in a. nidulans dna, resulted in the conversion of a high fraction of the cell population (more than 20%) to a mitotically and meiotically stable "fluffy" developmental phenotype. the phenotypic variants are characterized by the developmentally timed production of a profuse fluffy network of undifferentia ...19836197627
development of fluorescent-antibody reagents for demonstration of pseudallescheria boydii in tissues.we prepared fluorescent-antibody reagents to detect and identify pseudallescheria boydii in tissue. antisera to broken mycelium and condidia (particulate antigens) and to culture filtrates (soluble antigens) of p. boydii were produced in rabbits. antisera and globulin fractions of the antisera were labeled with fluorescein isothiocyanate and evaluated for their ability to stain p. boydii in tissues. the conjugates were first tested with cultures of 25 p. boydii isolates and 26 heterologous fungi ...19836195179
effect of alpha-amanitin and actinomycin d on rna synthesis in the protoplasts of aspergillus nidulans.rna synthesis was studied in protoplasts from aspergillus nidulans, which remained metabolically active for several days under the appropriate conditions. it is concluded, that at certain actinomycin d concentrations the ribosomal rna synthesis can be selectively inhibited. however, alpha-amanitin at concentrations up to 400 micrograms/ml neither influenced the total nor the rna polymerase ii directed rna synthesis. it was possible to discriminate between the rna polymerase i or ii directed rna ...19826186893
dna sequence of the region adjacent to the oxi1 and oxi2 genes from aspergillus nidulans mitochondrial dna. 19826184922
recombinogenic and mutagenic effects of the antitumor antibiotic bleomycin in aspergillus nidulans.bleomycin, an antibiotic and antineoplastic drug that inhibits dna synthesis and causes several types of chromosomal aberration, was found to increase mitotic recombination in aspergillus nidulans. heterozygous prototrophic diploid strains grown on media containing bleomycin produced significant increases of yellow and white sectors compared with controls. further, the increased colour segregants were due to mitotic crossing-over, whereas the non-dis junctional segregants remained at the control ...19826181398
the effect of the synergy between sterigmatocystin and a fungal metabolite on bacillus subtilis. 19826175614
the preparation and partial characterization of antigenic fractions obtained from the mycelial walls of several aspergillus species.extracts with immunological activity were prepared from aspergillus fumigatus, a. flavus, a. terreus, a. niger and a. nidulans. in each case crude mycelial wall was extracted with an aqueous solution of triton x-100 giving detergent-soluble material. further fractionation was achieved by removing the detergent from this solution; the resultant precipitate was removed by centrifugation, and the aqueous supernatant was used as a source of soluble antigens. the sensitivity of these preparations was ...19806157778
new leucine auxotrophs of aspergillus nidulans.a series of aspergillus nidulans leucine auxotrophs were isolated after nitroquinoline-1-oxide treatment and analyzed. four complementation groups could be distinguished in addition to the previously known leua group. a putative mutant for isopropylmalate isomerase (leub) was mapped on chromosome i and found to be closely linked to leua.19806155050
regulation of alcohol dehydrogenase (adh) and aldehyde dehydrogenase (alddh) in aspergillus nidulans. 19836132393
the regulation of nadp-linked isocitrate dehydrogenase in aspergillus nidulans.the regulation of nadp-linked isocitrate dehydrogenase (nadp-idh) has been studied in wild-type and mutant strains of aspergillus nidulans. in the wild-type strain studied, the levels of nadp-idh vary in a similar way to those of acetamidase, acetyl-coa synthase, isocitrate lyase and malate synthase under all growth conditions used. similarly, fac mutants, which are altered in the regulation of these enzymes of acetate utilization, are affected in nadp-idh levels in a parallel fashion, as are cr ...19826123545
l-histidine utilization in aspergillus nidulans.histidase activity rather than uptake of l-histidine is the limiting factor for the utilization of histidine as the sole nitrogen source for aspergillus nidulans. histidine cannot act as the sole carbon source, and evidence is presented indicating that this is attributable to an inability to convert histidine to l-glutamate in vivo. it has been shown that this fungus lacks an active urocanase enzyme and that histidine is quantitatively converted to urocanate, which accumulates in the extracellul ...19826120926
[the cyclic nucleotide system of aspergillus nidulans under the influence of methylbenzimidazol-2-ylcarbamate (mbc). i. a hypothetical mitosis model].the influence of methylbenzimidazol-2-yl carbamate (mbc) on the cyclic nucleotide system of germinating aspergillus nidulans conidia has been investigated throughout the cell cycle. the content in cyclic adenosine 3',5'-monophosphate (camp) and cyclic guanosine 3',5'-monophosphate (cgmp) is rapidly decreased in the course of conidia swelling and has been found not to be influenced by mbc. on the other hand, influence of mbc leads, in inhibited nuclear division, to a significant increase of the i ...19806106987
regulation of gene expression in aspergillus nidulans. 19846101115
genetic analysis of mutants of aspergillus nidulans blocked at an early stage of sporulation.three mutants of aspergillus nidulans, selected to have a block at an early stage of conidiation (asexual sporulation), exhibit similar pleiotropic phenotypes. each of these mutants, termed preinduction mutants, also are blocked in sexual sporulation and secrete a set of phenolic metabolites at level much higher than wild type or mutants blocked at later stages of conidiation. backcrosses of these mutants to wild type showed that the three phenotypes always cosegregated. diploids containing the ...19846094473
triton x-114 phase fractionation of membrane proteins of the cyanobacterium anacystis nidulans r2.the thylakoid polypeptides of the cyanobacterium anacystis nidulans r2 were analyzed by triton x-114 phase fractionation [c. bordier (1981) j. biol. chem. 256, 1604-1607, as adapted for photosynthetic membranes by t.m. bricker and l.a. sherman (1982) febs lett. 149, 197-202]. in this procedure, polypeptides with extensive hydrophobic regions (i.e., intrinsic proteins) form mixed micelles with triton x-114, and are separated from extrinsic proteins by temperature-mediated precipitation of the mix ...19846093709
the mitochondrial genome of the fission yeast schizosaccharomyces pombe: highly homologous introns are inserted at the same position of the otherwise less conserved cox1 genes in schizosaccharomyces pombe and aspergillus nidulans.the dna sequence of the second intron in the mitochondrial gene for subunit 1 of cytochrome oxidase (cox1), and the 3' part of the structural gene have been determined in schizosaccharomyces pombe. comparing the presumptive amino acid sequence of the 3' regions of the cox1 genes in fungi reveals similarly large evolutionary distances between aspergillus nidulans, saccharomyces cerevisiae and s. pombe. the comparison of exon sequences also reveals a stretch of only low homology and of general siz ...19846092057
three variant introns of the same general class in the mitochondrial gene for cytochrome oxidase subunit 1 in aspergillus nidulans.the oxia gene of aspergillus nidulans, coding for cytochrome oxidase subunit 1, is shown by dna sequencing to contain three introns. an aug start codon is not present at the beginning of the sequence, suggesting that either another codon, possibly the four base codon auga, is used for initiation or there is a further short intron between the true start codon and the beginning of the recognisable coding region. the second and third introns have long open reading frames, which could code for matur ...19846092056
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