TitleAbstractYear(sorted ascending)
[relation of bronchial asthma and allergic bronchopulmonary aspergillosis].an allergological examination was conducted in 30 out of 83 (36.07%) patients showing symptoms of bronchial asthma. it was found that skin hypersensitivity to aspergilla allergens coupled with a high serum ige level. the appropriateness of such affection referral to a separate nosological entity (allergic bronchopulmonary aspergillosis) is under discussion.19892697785
aspergillus nidulans as a test organism for the detection of chemically-induced mitotic crossing-over and chromosome malsegregation.the genetic systems developed in the mould aspergillus nidulans to study the chemical induction of mitotic genetic segregation were used to investigate the mechanism of aneuploidy induction by the main benzene hydroxy metabolites. detailed genetic analysis of mitotic segregants produced by individual colonies revealed the simultaneous occurrence of both whole chromosome segregants and mitotic cross-overs, i.e. a pattern not compatible with the induction of numerical abnormalities as the primary ...19892698601
keratinolytic fungi of wadi qena in egypt.forty-six soil samples collected from different sites of wadi qena were examined for keratinophilic fungi using the hair baiting technique. thirty-two species in addition to one variety of each of a. nidulans and a. flavus which belong to eighteen genera were recovered. aspergillus, chrysosporium, penicillium, microsporum and fusarium were the most frequent genera developed from baited soils.19892707686
partial characterization of the gene coding for subunit iv of soybean mitochondrial nadh using the spinach chloroplast atpe gene (epsilon-subunit coding gene) as a probe we have isolated, from a soybean mitochondrial dna library, a sequence containing a 405 base-pairs (bp) open-reading frame (orf). this orf, which is unique in the soybean mitochondrial genome, is probably part of an exon of the gene coding for subunit iv of the nadh dehydrogenase complex. the predicted protein shows 42% sequence similarity with the c-terminal region the aspergillus nidulans nad4 protein. the gene ...19892743433
improved transformation efficiency of aspergillus niger using the homologous niad gene for nitrate reductase.aspergillus niger transformation frequencies of up to 1,176 transformants per micrograms dna were achieved using the plasmid vector psta10 containing the a. niger nitrate reductase structural gene. analysis of genomic endonuclease cleaved dna from nitrate utilising transformants by dna hybridisation, showed that most integration events are as a result of homologous recombination. the niad transformation system was used successfully for the introduction of the unselected escherichia coli fusion g ...19892791035
botran and bleomycin induce crossing-over, and bleomycin also increases aneuploidy in diploid strains of aspergillus.both bleomycin, an antineoplastic drug, and botran (2,6-dichloro-4-nitro-aniline), a fungicide, are known to inhibit growth and induce genetic segregation in diploid tester strains of aspergillus nidulans when present in agar media. to identify primary effects, samples of induced apparent crossover types were analysed in detail. for both compounds, coincident and consecutive events of mitotic crossing-over were found to be very frequent and such events showed a random distribution among isolated ...19901692105
characterization and comparison of mitochondrial dnas and rrnas from penicillium urticae and p. chrysogenum.mitochondrial dna (mt dna) from a patulin producer, penicillium urticae (synonym p. griseofulvum), was 27.8 kb +/- 0.6 kb in size by electron microscopy and 27.2 kb by agarose gel electrophoresis. restriction endonuclease maps for nine restriction enzymes were constructed, and eleven fragments which covered the total range of the mt dna were cloned into the escherichia coli plasmid vector puc19. southern analysis of the native genomes of p. urticae and p. chrysogenum with six of the cloned fragm ...19901697325
a negative regulator of mitosis in aspergillus is a putative membrane-spanning protein.the temperature-sensitive cell cycle mutation bime7 of aspergillus nidulans causes cells to become blocked in mitosis at a restrictive temperature. previous work has shown that this mitotic block is induced even when cells are arrested in the s or g2 phase. the mitotic block is also observed in cells carrying a null mutation in bime, obtained by molecular disruption of the gene (osmani, s.a., engle, d.b., doonan, j.h., and morris, n.r. (1988) cell 52, 241-251), indicating that a lack of bime fun ...19901697851
optimized vectors and selection for transformation of neurospora crassa and aspergillus nidulans to bleomycin and phleomycin provide a dominant selectable marker for transformation of neurospora crassa strains lacking specific auxotrophic mutations, we have engineered the bleomycin (bm) resistance-encoding gene (ble) from the bacterial transposon tn5 for expression in n. crassa. the coding region of the ble gene was fused to the promoter and terminator regions of the n. crassa am gene. in some vectors, multiple cloning sites were placed flanking the ble gene to provide a versatile ble cassette. when introduced into ...19901699844
keratinophilic fungi and other moulds associated with air-dust particles from and eleven species and three species varieties belonging to 39 genera were collected from 50 dust samples on the five media used at 28 degrees c. using the hair-baiting technique with horse hair, 10 species of chrysosporium were isolated: c. asperatum, c. state of arthroderma tuberculatum, c. indicum, c. inops, c. keratinophilum, c. merdarium, c. pannorum, c. queenslandicum, c. tropicum and c. xerophilum. true dermatophytes were isolated: trichophyton verrucosum and trichophyton sp. ...19901702081
the regulatory gene area mediating nitrogen metabolite repression in aspergillus nidulans. mutations affecting specificity of gene activation alter a loop residue of a putative zinc finger.the regulatory gene area mediating nitrogen metabolite repression in aspergillus nidulans has been sequenced and its transcript mapped and orientated. a single orf can encode a protein of 719 amino acids. a 52 amino acid region including a putative 'zinc finger' strongly resembles putative dna binding regions of the major regulatory protein of erythroid cells. the derived protein sequence also contains a highly acidic region possibly involved in gene activation and 22 copies of the motif s(t)pxx ...19901970293
comparison and cross-species expression of the acetyl-coa synthetase genes of the ascomycete fungi, aspergillus nidulans and neurospora crassa.the genes encoding the acetate-inducible enzyme acetyl-coenzyme a synthetase from neurospora crassa and aspergillus nidulans (acu-5 and faca, respectively) have been cloned and their sequences compared. the predicted amino acid sequence of the aspergillus enzyme has 670 amino acid residues and that of the neurospora enzyme either 626 or 606 residues, depending upon which of the two possible initiation codons is used. the amino acid sequences following the second alternative aug show 86% homology ...19901972535
restriction enzyme analysis of mitochondrial dna of the aspergillus flavus group: a. flavus, a. parasiticus, and a. nomius.mitochondrial dna restriction fragment length polymorphisms were identified that clearly distinguish aspergillus flavus, a. parasiticus, and a. nomius. mitochondrial dnas of a. flavus and a. parasiticus were found to be circular, and their size was estimated size to be 32 kilobases. a restriction map was constructed for the mitochondrial genome of an a. parasiticus isolate by using four restriction endonucleases. four genes tested were found to have the same order as in the mitochondrial genome ...19901976299
use of nuclear dna restriction fragment length polymorphisms to analyze the diversity of the aspergillus flavus group: a. flavus, a. parasiticus, and a. nomius.recombinant dna clones carrying high-copy or low-copy sequences from aspergillus nidulans and neurospora crassa were used to identify restriction fragment length polymorphisms (rflps) diagnostic for members of the a. flavus group: a. flavus, a. parasiticus, and a. nomius. these fungi were resolved into three distinct categories when they were grouped according to rflp patterns. subgroups within these categories were also evident. this limited rflp analysis of nuclear dna of members of the a. fla ...19901976300
premeiotic disruption of the neurospora crassa malate synthase gene by native and divergent dnas.repeat-induced point mutation (rip) has been used to generate new mutations in the previously uncharacterised gene for malate synthase in neurospora crassa. molecular clones carrying the am (nadp-glutamate dehydrogenase) gene and the malate synthase gene from either n. crassa or aspergillus nidulans have been introduced into neurospora as ectopic duplicate copies by transformation, selecting for the am+ function in a deletion host. a number of meiotic progeny derived from these transformants wer ...19901979142
sequences of isopenicillin n synthetase genes suggest horizontal gene transfer from prokaryotes to eukaryotes.evolutionary distances between bacterial and fungal isopenicillin n synthetase (ipns) genes have been compared to distances between the corresponding 5s rrna genes. the presence of sequences homologous to the ipns gene has been examined in dnas from representative prokaryotic organisms and ascomycotina. the results of both analyses strongly support two different events of horizontal transfer of the ipns gene from bacteria to filamentous fungi. this is the first example of such a type of transfer ...19901979440
restriction fragment length polymorphisms in isolates of aspergillus fumigatus probed with part of the intergenic spacer region from the ribosomal rna gene complex of aspergillus nidulans.differences in restriction fragment length polymorphisms (rflps) have been detected in isolates of aspergillus fumigatus. genomic dna from 11 isolates was digested with ecori, separated by electrophoresis, southern blotted and probed with dna from the intergenic spacer or non-transcribed spacer region of the rrna gene complex of aspergillus nidulans. three distinct rflp patterns were detected which differed from the control patterns observed with a. nidulans, aspergillus flavus and aspergillus n ...19901980128
expression of the aspergillus niger glucose oxidase gene in a. niger, a. nidulans and saccharomyces cerevisiae.we report the cloning of the aspergillus niger glucose oxidase gene and its use to elevate glucose oxidase productivity in a. niger by increasing the gene dosage. in addition, the gene has been introduced into a. nidulans where it provides the novel capacity to produce glucose oxidase. a plasmid, in which dna encoding the mature form of glucose oxidase was preceded by a saccharomyces cerevisiae secretion signal, effected high-level production of extracellular glucose oxidase in this yeast.19902076553
genetic analysis of suppressors of the vea1 mutation in aspergillus nidulans.light-dependent conidiation in the filamentous ascomycete, aspergillus nidulans, is contingent on the allelic state of the velvet (vea) gene. light dependence is abolished by a mutation in this gene (vea1), which allows conidiation to occur in the absence of light. we have isolated and characterized six extragenic suppressors of vea1 that restore the light-dependent conidiation phenotype. alleles of four genes, defined by complementation tests, were subjected to extensive genetic and phenotypic ...19902076818
fungi of virgin and cultivated soil of salhiah desert, egypt.27 species and 13 genera of fungi were identified from virgin and cultivated soil of salhiah. the most abundant species of phosphate solubilizing fungi were aspergillus nidulans, a. niger, a flavus, penicillium lilacinum, p. frequentans and fusarium moniliforme. on cellulose agar the most prevalent species were chaetomium bostrychodes, c. olivaceum, humicola fuscoatra, aspergillus flavus, a. nidulans, a. niger, a. ochraceus, fusarium solani and f. oxysporum. on xylan agar aspergillus fumigatus, ...19902077791
structure and molecular mechanics of ferrirhodin.c41h64fen9o17.7 1/2h2o, mr = 1146.0, orthorhombic, p2(1)2(1)2(1), a = 9.740 (7), b = 16.764 (10), c = 32.632 (17) a, v = 5328 (6) a3, z = 4, d chi = 1.43 g cm-3, mo k alpha, lambda = 0.71069 a, mu = 3.26 cm-1, f(000) = 2428, t = 138 (2) k, r = 0.0986 for 3543 observed reflections. ferrirhodin, a ferrichrome siderophore (iron transport agent) was isolated from low-iron cultures of aspergillus versicolor and a. nidulans. the compound is isomeric with another microbial siderophore, ferrirubin, but ...19902088417
beta-lactam antibiotic biosynthetic genes have been conserved in clusters in prokaryotes and eukaryotes.a cosmid clone containing closely linked beta-lactam antibiotic biosynthetic genes was isolated from a gene library of flavobacterium sp. sc 12,154. the location within the cluster of the dna thought to contain the gene for delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase (acvs), the first step in the beta-lactam antibiotic biosynthetic pathway, was identified by a novel method. this dna facilitated the isolation, by cross-hybridization, of the corresponding dna from streptomyces clav ...19902107074
a critical arginine in the large subunit of ribulose bisphosphate carboxylase/oxygenase identified by site-directed mutagenesis.rapid inactivation by phenylglyoxal of ribulose bisphosphate carboxylase/oxygenase (ribulose-p2 carboxylase) from the cyanobacterium anacystis nidulans suggests the presence of an essential arginine, the modification of which is reduced in the presence of the substrate ribulose bisphosphate. arginine 292 in the large subunit of ribulose-p2 carboxylase from a. nidulans was chosen for site-directed mutagenesis studies on the basis of the complete conservation of this residue in corresponding seque ...19902108139
brla requires both zinc fingers to induce development.expression of the aspergillus nidulans brla gene induces a developmental pathway leading to the production of asexual spores. we have introduced mutations into brla that are expected to disrupt either or both cys2-his2 zn(ii) coordination sites postulated to exist in the brla polypeptide. the resultant brla alleles fail to induce either the asexual reproductive pathway or the expression of development-specific genes. these data support the hypothesis that brla encodes a nucleic acid-binding prot ...19902108321
acyl coenzyme a: 6-aminopenicillanic acid acyltransferase from penicillium chrysogenum and aspergillus nidulans.a study of the final stages of the biosynthesis of the penicillins in penicillium chrysogenum has revealed two types of enzyme. one hydrolyses phenoxymethyl penicillin to 6-aminopenicillanic acid (6-apa). the other, also obtained from aspergillus nidulans, transfers a phenylacetyl group from phenylacetyl coa to 6-apa. the acyltransferase, purified to apparent homogeneity, had a molecular mass of 40 kda. it also catalyses the conversion of isopenicillin n (ipn) to benzylpenicillin (pen g) and hyd ...19902110531
cloning and expression of a hybrid streptomyces clavuligerus cefe gene in penicillium chrysogenum.a hybrid cefe gene was constructed by juxtaposing promoter sequences from the penicillium chrysogenum pcbc gene to the open reading frame of the streptomyces clavuligerus cefe gene. in s. clavuligerus the cefe gene codes for the enzyme penicillin n expandase [also known as deacetoxycephalosporin c synthetase (daocs)]. to insert the hybrid cefe gene into p. chrysogenum the vector pps65 was constructed; pps65 contains the hybrid cefe gene and the aspergillus nidulans amds gene. the amds gene encod ...19902111228
characterization of cryptic plasmids from marine cyanobacteria and construction of a hybrid plasmid potentially capable of transformation of marine cyanobacterium, synechococcus sp., and its transformation.among forty strains of marine cyanobacteria isolated in our laboratory, five strains had 1-3 different plasmids. the unicellular marine cyanobacterium, synechococcus sp. nkbg 042902, contains at least three plasmids (psy09, psy10, and psy11). however, these plasmids are cryptic. therefore, a hybrid plasmid pusy02 containing the 1.4-kb hindiii fragment of psy11 and escherichia coli plasmid puc18 was constructed. the plasmid pusy02 transformed both marine synechococcus sp. nkbg042902-yg1116, which ...19902112896
the upstream region of the ipns gene determines expression during secondary metabolism in aspergillus nidulans.we have constructed a translational fusion between the isopenicillin-n-synthetase-encoding gene (ipns) of aspergillus nidulans and the lacz gene of escherichia coli. recombinant strains carrying a single copy of the fusion integrated at the ipns locus produced beta-galactosidase (beta gal) during secondary metabolism. integration of the fusion at the argb locus results in a situation in which the only 5'-flanking sequences of the ipns gene upstream from the chimeric fused gene are those included ...19902115487
upstream elements repress premature expression of an aspergillus developmental regulatory gene.the aspergillus nidulans abaa gene regulates intermediate steps in asexual reproductive development and is itself developmentally regulated. an 822-base-pair dna fragment from the abaa 5'-flanking region is sufficient to drive developmentally appropriate expression of the escherichia coli lacz gene. deletion analysis showed that this fragment contains elements that repress transcription in vegetative cells and immature conidiophores and that activate transcription later during development. a 45- ...19902117702
a case of cerebral aspergillosis caused by aspergillus nidulans. clinical, pathologic and mycologic identifications.a case of cerebral aspergillosis is reported, the presenting symptom was numbness of right face, which worsened after one year. ct-scan showed two enhanced low-density patches in the anterior and basal parts of right temporal lobe. during operation, an abscess in the deep part of right temporal lobe was revealed. the patient gradually felt amaurosis and oculomotor palsy of right eye. about six months later, she died from intracranial hypertension. biopsy, as well as autopsy findings suggested fu ...19902119968
molecular characterization of the acyl-coenzyme a:isopenicillin n acyltransferase gene (pende) from penicillium chrysogenum and aspergillus nidulans and activity of recombinant enzyme in escherichia coli.the final step in the biosynthesis of beta-lactam antibiotics in penicillium chrysogenum and aspergillus nidulans involves removal of the l-alpha-aminoadipyl side chain from isopenicillin n (ipn) and exchange with a nonpolar side chain. the enzyme catalyzing this reaction, acyl-coenzyme a:isopenicillin n acyltransferase (acyltransferase), was purified from p. chrysogenum and a. nidulans. based on nh2-terminal amino acid sequence information, the acyltransferase gene (pende) from p. chrysogenum a ...19902120195
functional expression of 8-hydroxy-5-deazaflavin-dependent dna photolyase from anacystis nidulans in streptomyces coelicolor.the gene encoding anacystis nidulans 5-deazaflavin-dependent photolyase (phr) was inserted into the streptomyces vector pij385 to form a transcriptional fusion with the neomycin resistance (aph) gene. the resulting plasmid, panpl, was introduced into streptomyces coelicolor, a host which exhibits no detectable photolyase activity and provides 5-deazaflavins. transformants expressed functional photolyase and could be cultured at much higher cell densities than a. nidulans. a two-step affinity pro ...19902120199
analysis of delta-l-alpha-aminoadipyl-l-cysteinyl-d-valine by ion chromatography and pulsed amperometric detection.a novel high-performance liquid chromatography (hplc) method is presented for the detection and trace level determination of the tripeptide delta-l-alpha-aminoadipyl-l-cysteinyl-d-valine (acv). the tripeptide, an intermediate in penicillin production, is derived from fungal fermentation. the technique relies on ion-exchange separation of the tripeptide on an anion-exchange column followed by detection by reduction on a gold electrode using pulsed amperometry. the sensitivity of direct determinat ...19902120274
qualitative and quantitative changes in beta-1,4-glucosidase accompanying growth of aspergillus nidulans.a comparative study of the wild type a. nidulans and a mutant strain aco-t69 (lacking conidia and cleistothecia) revealed the better production of beta-1,4-glucosidase in the former. the relative distribution of the enzyme levels in various morphological structures viz. somatic hyphae, spores and cleistothecia also showed a variation. highest specific activity was found in the cleistothecial extracts. the electrophoretic analysis of the wild type strain demonstrated the presence of three isoenzy ...19902120420
functional elements in the promoter region of the aspergillus nidulans gpda gene encoding glyceraldehyde-3-phosphate dehydrogenase.analysis of the promoter region of the highly expressed aspergillus nidulans gpda gene is described. the nucleotide (nt) sequence of a 1.3-kb region upstream from the atg was determined. comparison with promoter regions of other aspergillus and neurospora genes revealed several regions of similar sequence. both random and site-specific mutations were introduced into the promoter region of the gpda gene, and the resulting mutant promoters were fused to the escherichia coli lacz gene. the construc ...19902121607
n-acetyl-6-hydroxytryptophan oxidase, a developmentally controlled phenol oxidase from aspergillus nidulans.we have purified a specific phenol oxidase which is produced during conidiophore development in the fungus aspergillus nidulans. two active forms (a and b) have molecular masses of 50 and 48 kda respectively; they have identical n-termini (24 residues). we have analysed the metal ion content of the b form; it is unusual in consisting of one zinc and two copper atoms per molecule. a temperature-sensitive mutant (ivob192) produces a thermolabile enzyme, implying that ivob is the structural locus. ...19902126551
isolation and sequence analysis of a beta-tubulin gene from aspergillus flavus and its use as a selectable altered beta-tubulin gene that confers resistance to benomyl [whose active ingredient is 2-(methoxycarbonylamino)benzimidazole (mbc)] was isolated from a dna library of aspergillus flavus and used as a selectable marker for transformation. the beta-tubulin gene was cloned into a plasmid vector containing the pyr-4 gene of neurospora crassa, and transformants were selected either for uracil prototrophy or mbc resistance. transformants selected for uracil prototrophy were of three phenotypic cl ...19902128007
[lung mycoses caused by opportunistic fungi]. 19902128860
mutation of a gene that encodes a kinesin-like protein blocks nuclear division in a. a. nidulans, the temperature-sensitive cell cycle mutation bimc4 causes an elevated mitotic index at restrictive temperature. under restrictive conditions the mutation interferes with separation of the spindle pole bodies, causes abnormal spindle morphology, and prevents nuclear division. we have cloned and sequenced the wild-type bimc gene. the predicted protein product has homology to drosophila kinesin heavy chain. we conclude that this kinesin-like protein has an important role in nuclear ...19902138511
adenosine triphosphatases in p-fluorophenylalanine sensitive and resistant strains of aspergillus nidulans. 19902144842
immunoprecipitation distinguishes non-overlapping groups of snrnps in schizosaccharomyces pombe.the large number of snrnas in the fission yeast schizosaccharomyces pombe can be divided into four non-overlapping groups by immunoprecipitation with antibodies directed against mammalian snrnp proteins. 1) of the abundant snrnas, anti-sm sera precipitate only the spliceosomal snrnas u1, u2, u4, u5 and u6. surprisingly, three sm-sera tested distinguish between u2, u4 and u5 and u1 from s.pombe; one precipitating only u1 and two precipitating u2, u4 and u5 but not u1. 2) a group of 11 moderately ...19902144896
novel potential mitotic motor protein encoded by the fission yeast cut7+ gene.the structure equivalent to higher eukaryotic centrosomes in fission yeast, the nuclear membrane-bound spindle pole body, is inactive during interphase. on transition from g2 to m phase of the cell cycle, the spindle pole body duplicates; the daughter pole bodies seed microtubules which interdigitate to form a short spindle that elongates to span the nucleus at metaphase. we have identified two loci which, when mutated, block spindle formation. the predicted product of one of these genes, cut7+, ...19902145514
the beta-tubulin gene of epichloë typhina from perennial ryegrass (lolium perenne).epichloë typhina is a biotrophic fungal pathogen which causes choke disease of pooid grasses. the anamorphic state, acremonium typhinum, is placed in the section albo-lanosa along with related, mutualistic, seed-disseminated endophytes. as an initial study of gene structure and evolution in epichloë and related endophytes, the beta-tubulin gene, tub2, of the perennial ryegrass choke pathogen (etprg) was cloned and sequenced. the coding sequence and the predicted beta-tubulin amino acid sequence ...19902147581
[host-vector systems in filamentous fungi]. 19902148397
induced expression of the aspergillus nidulans qute gene introduced by transformation into neurospora crassa.the qa-2 gene of neurospora crassa encodes catabolic dehydroquinase which catabolizes dehydroquinic acid to dehydroshikimic acid. the qute gene of aspergillus nidulans corresponds to the qa-2 gene of n. crassa. the plasmid peh1 containing the qute gene from a. nidulans was used to transform a qa-2- strain of n. crassa. in southern blot analyses, dnas isolated from these transformants hybridized specifically to the qute gene probe. northern blot analyses indicated that qute mrna was produced in t ...19902148798
of moulds and men, or two fingers are not better than one. 19902149222
abaa controls phialide differentiation in aspergillus nidulans.aspergillus nidulans is an ascomycetous fungus that reproduces asexually by forming multicellular conidiophores and uninucleate spores called conidia. loss of function mutations in the abacus a (abaa) regulatory locus result in formation of aberrant conidiophores that fail to produce conidia. wild-type conidiophores form two tiers of sterigmata. the first tier, metulae, divide to produce the second tier, phialides. phialides are sporogenous cells that produce conidia through a specialized apical ...19902152124
cloned manganese superoxide dismutase reduces oxidative stress in escherichia coli and anacystis nidulans.the mn superoxide dismutase gene of escherichia coli was subcloned into the e. coli-anacystis nidulans shuttle vector psg111 to make the plasmid pmyg1. transformation of e. coli hb101 with pmyg1 resulted in a 6-fold increase in superoxide dismutase activity. there was also induction of mn superoxide dismutase in the transformants upon exposure to paraquat, as evidenced by dramatically increased levels of the mn superoxide dismutase polypeptide in cytoplasmic extracts and a 16-fold further increa ...19902157207
endo-exonuclease of aspergillus nidulans.endo-exonuclease (ee) has been found in both active and inactive, but trypsin-activatable, forms in aspergillus nidulans. active ee was present mainly in nuclei, mitochondria, and vacuoles, while trypsin-activatable ee was mainly in the cytosol. the active form accounts for over 90% of the neutral deoxyribonuclease activity extracted from mycelia. a single strand (ss) dna-binding ee associated with a 28 kilodalton (kda) polypeptide was partially purified and characterized. it was found to closel ...19902161674
regulation of inorganic sulfate activation in filamentous fungi. allosteric inhibition of atp sulfurylase by 3'-phosphoadenosine-5'-phosphosulfate.atp sulfurylases from penicillium chrysogenum, penicillium duponti, aspergillus nidulans, and neurospora crassa are strongly inhibited by 3'-phosphoadenosine-5'-phosphosulfate (paps), the product of the second (adenosine-5'-phosphosulfate kinase-catalyzed) reaction in the two-step activation of inorganic sulfate. the v versus [paps] plots are sigmoidal. at physiological concentrations of mgatp (0.17-3 mm) and so4(2-) (0.4-10 mm), the [i]0.5 for paps inhibition of the p. chrysogenum enzyme is 35- ...19902162344
cloning, characterization of the acyl-coa:6-amino penicillanic acid acyltransferase gene of aspergillus nidulans and linkage to the isopenicillin n synthase gene.the pende gene encoding acyl-coa:6-amino penicillanic acid acyltransferase (aat), the last enzyme of the penicillin biosynthetic pathway, has been cloned from the dna of aspergillus nidulans. the gene contains three introns which are located in the 5' region of the open reading frame. it encodes a protein of 357 amino acids with a molecular weight of 39,240 da. the pende gene of a. nidulans shows 73% similarity at the nucleotide level with the pende gene of penicillium chrysogenum. the a. nidula ...19902166227
efficient integrative transformation of the phytopathogenic fungus alternaria alternata mediated by the repetitive rdna attempt was made to transform alternaria alternata protoplasts using a plasmid vector, pdh25, bearing the escherichia coli hygromycin b (hy) phosphotransferase gene (hph) under the control of the aspergillus nidulans trpc promoter. transformants arose on a selective medium containing 100 micrograms hy/ml. there were two types of transformants, forming large and small colonies on the selective medium. transformation with one microgram of the vector produced an average of 4.5 large colonies and ...19902169442
insertional inactivation and cloning of the wa gene of aspergillus nidulans.we describe examples of wa gene inactivation (resulting in white conidiospores) obtained during transformation of aspergillus nidulans. one wa- transformant was obtained by transformation with a prn+ plasmid of a strain with green conidia (wa+) which was unable to catabolize l-proline (prn-). this transformant contains a very large number of plasmid copies integrated at a single site inseparable from the wa locus. passage of this transformant through the sexual cycle generated a variety of novel ...19902172077
spatial and biological characterisation of the complete quinic acid utilisation gene cluster in aspergillus nidulans.heterologous probing of restriction digests of chromosomal dna from aspergillus nidulans with radioactively labelled probes encoding dehydroshikimate dehydratase (qa-4) and a repressor gene (qa1-s) from neurospora crassa revealed a pattern of hybridisation inconsistent with an equivalent single copy of each gene in a. nidulans. screening of size-selected and total genome a. nidulans dna libraries allowed the isolation of four unique classes of sequence, two of which hybridised to the qa-4 probe, ...19902175387
transformation of aspergillus giganteus to hygromycin b resistance.a wild strain of a. giganteus was transformed to hygromycin b resistance using a bacterial resistance gene under the control of a. nidulans sequences. stable transformants arose by heterogenous integration, mainly of tandem repeats of vector dna at various sites in the host genome. between 6 and 30 resistant colonies were obtained per microgram dna per 3 x 10(3) viable protoplasts. vector dna could be recovered by transformation of escherichia coli with undigested genomic dna from aspergillus gi ...19902178785
chromosomal mapping of an alcc disruption with respect to amda in aspergillus nidulans.we report the use of the ribob gene for a gene replacement in the alcc gene of aspergillus nidulans, and show by "reverse genetics" that the alcc gene is very closely linked to the amda gene.19902178787
purification and characterization of cellulolytic enzymes produced by aspergillus nidulans.three exo-glucanases, two endo-glucanases and two beta-glucosidases were separated and purified from the culture medium of aspergillus nidulans. the optimal assay conditions for all forms of cellulase components ranged from ph 5.0 to 6.0 and 50 degrees c and 65 degrees c for exo-glucanases and endo-glucanases but 35 degrees c and 65 degrees c for beta-glucosidases. a close relation of enzyme stability to their optimal ph range was observed. all the cellulase components were stable for 10 min at ...19902179198
genotoxicity studies on the organophosphorus insecticide chloracetophone.chloracetophone (o,o-dimethyl-2,2,2-trichloro-1-(chloroacetoxy)phosphonate), a new insecticide of the organophosphorus group of pesticides, was tested for genotoxicity in a variety of systems with different genetic end-points and varying parameters. the test systems included 2 microbial systems, salmonella and aspergillus for point mutations and mitotic segregation, respectively, and human lymphocyte cultures and mammalian bone marrow cells (from rats and hamsters treated acutely and subacutely) ...19902179715
conidium differentiation in aspergillus nidulans wild-type and wet-white (weta) mutant strains.conidium (asexual spore) differentiation in wild-type and the wet-white (weta) mutant of aspergillus nidulans was compared in intact chains of successively older conidia. carbohydrate cytochemistry helped define three stages (stages i, ii, and iii) of wild-type conidium maturation on the basis of changes in the ultrastructure and composition of the conidium wall. conidia of the weta6 mutant strain formed normally but failed to mature during stages ii and iii. specifically, the inner wall layer o ...19902180753
mutants of aspergillus nidulans able to grow at extremely acidic ph acidify the medium less than wild type when grown at more moderate ph.mutations conferring the ability to grow on extremely acidic media have been selected in the fungus aspergillus nidulans and map to at least four genes. the mutations fall into two classes: those that confer acid resistance in media of both high and low buffering capacity and those that confer resistance only in media of low buffering capacity. in growth media of more moderate ph mutations of both classes result in reduced acidification of the medium.19902182381
a mutation affecting amds expression in aspergillus nidulans contains a triplication of a cis-acting regulatory aspergillus nidulans expression of the acetamidase structural gene, amds, is under the control of at least four regulatory genes including the trans-acting amda regulatory gene. a cis-acting mutation (amdi66) consisting of an 18 bp duplication in the 5' region of the amds gene results in very high levels of acetamidase activity but only in strains carrying semi-dominant mutations in the amda gene. in selecting for increased amds expression in an amdi66 and a+ strain, an a. nidulans strain wit ...19902187153
chloroacetaldehyde is a powerful inducer of mitotic aneuploidy in aspergillus nidulans.the vinyl chloride metabolite chloroacetaldehyde (caa) was tested for the induction of mitotic chromosome malsegregation in aspergillus nidulans. exposure of germinating conidia to caa (16-64 microm) produced high rates of abnormal colonies with segregation of the whole first chromosome in the diploid strain p1, and abnormal, putative hyperploids in the haploid strain 35, indicating that caa primarily induces abnormal chromosome segregation. comparative assays with the known spindle poison chlor ...19902188069
sequence and functional analysis of the positively acting regulatory gene amdr from aspergillus nidulans.the positively acting regulatory gene amdr of aspergillus nidulans coordinately regulates the expression of five structural genes involved in the catabolism of certain amides (amds), omega amino acids (gata and gaba), and lactams (lama and lamb) in the presence of omega amino acid inducers. analysis of the amdr gene showed that it contains three small introns, heterogeneous 5' and 3' transcription sites, and multiple aug codons prior to the major aug initiator. the predicted amdr protein sequenc ...19902188110
isozyme polymorphism of endo-beta-1,4-glucanase in aspergillus electrophoretic survey of the natural populations of aspergillus nidulans, the a. nidulans group, and various species belonging to the genus aspergillus from diverse geographical areas of india was carried out to determine the isozyme polymorphism of endoglucanase. the data revealed the presence of three forms of endoglucanase designated eg i, eg ii, and eg iii. in some isolates, eg i and eg ii were present separately; in others, instead of two separate bands, one thick band was detected, whi ...19902188645
complementation of the aspergillus nidulans arg b1 mutation by ornithine transcarbamylase cdna from rat aspergillus nidulans strain which is deficient in ornithine transcarbamylase due to the arg b1 mutation was transformed with a plasmid containing the ornithine transcarbamylase cdna from rat liver under the control of the amd s promoter. stable transformants were obtained by selection on arginine free medium indicating complementation of the arg b mutation. proof of expression of the rat enzyme in transformants was obtained by immunoprecipitation of all ornithine transcarbamylase activity fro ...19902189407
sequence and molecular structure of the aspergillus nidulans ya (laccase i) gene. 19902192364
nucleotide sequences of the meta-cleavage pathway enzymes 2-hydroxymuconic semialdehyde dehydrogenase and 2-hydroxymuconic semialdehyde hydrolase from pseudomonas cf600.the nucleotide sequence of a 2493 base pair (bp) region, spanning the coding regions for the meta-cleavage pathway enzymes 2-hydroxymuconic semialdehyde dehydrogenase (hmsd) and 2-hydroxymuconic semialdehyde hydrolase (hmsh), was determined. the deduced protein sequence for hmsd is 486 amino acid residues long with an mr of 51,682. hmsd has homology with a number of aldehyde dehydrogenases from various eukaryotic sources. the deduced protein sequence for hmsh is 283 amino acids long with an mr o ...19902194577
gamma-tubulin is a component of the spindle pole body that is essential for microtubule function in aspergillus nidulans.we have recently discovered that the mipa gene of a. nidulans encodes gamma-tubulin, a new member of the tubulin superfamily. to determine the function of gamma-tubulin in vivo, we have created a mutation in the mipa gene by integrative transformation, maintained the mutation in a heterokaryon, and determined the phenotype of the mutation in spores produced by the heterokaryon. the mutation is lethal and recessive. it strongly inhibits nuclear division, less strongly inhibits nuclear migration, ...19902194669
increasing tubc beta-tubulin synthesis by placing it under the control of a bena beta-tubulin upstream sequence causes a reduction in bena beta-tubulin level but has no effect on microtubule function.we have constructed a chimeric beta-tubulin gene that places the structural gene for the tubc beta-tubulin of aspergillus nidulans under the control of the bena beta-tubulin promoter. introduction of either this chimeric gene or a second wild-type bena gene into a benomyl-resistant bena22 strain causes it to become benomyl sensitive, indicating that the introduced genes are functional. analysis of the tubulin proteins synthesized in bena22 strains into which a second wild-type bena beta-tubulin ...19902194681
developmental repression of growth and gene expression in aspergillus.asexual reproductive development can be initiated in aspergillus nidulans in the presence of excess nutrients through artificial induction of the developmental regulatory genes brla or abaa by fusing the genes to the promoter from the alcohol dehydrogenase i gene (alca) and culturing cells in the presence of an inducing alcohol. artificially induced development completely inhibits growth and represses expression of the endogenous alca gene and the coordinately controlled aldehyde dehydrogenase g ...19902196567
frequency of spontaneous and induced recessive mutations in a diploid strain of aspergillus nidulans.the spontaneous and uv-induced frequencies of recessive mutations have been studied in a diploid strain of aspergillus nidulans, by the p-fluoro-phenylalanine (fpa) and 8-azaguanine (8-aza) resistance tests, on either resting or germinating conidia. observed frequencies are in the order of magnitude of those expected, which have been calculated considering the observed mutation frequencies in the haploid strain as well as the mitotic recombination frequencies. we also review some papers which cl ...19902197553
cloning of the dna repair gene, uvsf, by transformation of aspergillus a first step in the cloning of the dna repair gene uvsf of aspergillus nidulans, uvsf pyrg double mutant strains were transformed with a genomic library which carried the complementing neurospora pyr-4 gene in the vector. rare pyr+ uvs+ cotransformants were obtained on media lacking pyrimidines, overlayed with mms (methyl-methane sulfonate) to which uvsf is hypersensitive. among mms-resistant transformants, southerns revealed two types which showed single bands of different sizes when bglii-d ...19902199316
characterization and expression of the unique calmodulin gene of aspergillus nidulans.complete cdna and genomic clones for the unique calmodulin (cam) gene of the filamentous fungus aspergillus nidulans have been isolated and characterized. the gene contains five introns, of which three are at unique positions relative to other cam genes. the a. nidulans cam gene is transcribed as a single, 0.85-kilobase mrna species that encodes a predicted protein 84% identical (93% similar if conservative changes are considered) to vertebrate cam. the complete cdna was ligated into a lambda pl ...19902199442
the molecular cloning and identification of a gene product specifically required for nuclear movement in aspergillus nidulans.a temperature-sensitive mutation in the nudc gene (nudc3) of aspergillus nidulans specifically prevents the microtubule-based movement of nuclei in this organism at the restrictive temperature. the mutation does not affect short term growth, nuclear division, or the movement of other subcellular organelles. immunofluorescence analysis of cells blocked at the restrictive temperature, using antitubulin antibodies, shows that the inability of nuclei to move under these conditions is not related to ...19902199460
purification and properties of nadp(+)-dependent glycerol dehydrogenases from aspergillus nidulans and a. niger.glycerol dehydrogenase, nadp(+)-specific (ec, was purified from mycelium of aspergillus nidulans and aspergillus niger using different purification procedures. both enzymes had an mr of approximately 38,000 and were immunologically cross-reactive, but had different amino acid compositions and isoelectric points. for both enzymes, the substrate specificity was limited to glycerol and erythritol for the oxidative reaction and to dihydroxyacetone (dha), diacetyl, methylglyoxal, erythrose ...19902200840
an inversion truncating the crea gene of aspergillus nidulans results in carbon catabolite derepression.the cread-30 mutation leading to carbon catabolite derepression in aspergillus nidulans is a pericentric inversion, having one breakpoint within the crea gene on the left arm of chromosome i and the other breakpoint between bing and ya on the right arm. the left-arm breakpoint alters the crea transcript. the likelihood that the inversion truncates crea centrally strengthens a previous proposal that derepression is the phenotype of loss-of-function mutations in crea.19902201871
p-fluoro-phenylalanine resistance in aspergillus nidulans diploid cells: evidence that dominant, lethal mutations are unexpectedly large number of p-fluoro-phenylalanine (fpa)-resistant mutants have been recovered after uv-irradiation of wild type diploid conidia of aspergillus nidulans. at least five different classes of mutants, possibly corresponding to five different loci, have been identified. two of them may be the dominant loci which have already been described but the others (a minimum of three loci) are completely different. mutations in these loci confer high level fpa resistance in the heterozygou ...19902202526
on the validation of the system of aspergillus for testing environmental aneugens. 19902203009
isolation and characterisation of the crna-niia-niad gene cluster for nitrate assimilation in aspergillus nidulans.genomic clones containing the entire crna-niia-niad gene cluster of aspergillus nidulans have been isolated, and the structures of the niia and niad genes have been determined by nucleotide sequence analysis. this gene cluster is required for the assimilation of nitrate in a. nidulans, and the three genes encode a product required for nitrate uptake and the enzymes, nitrite reductase and nitrate reductase, respectively. the putative coding sequences, as deduced by comparison to cdna clones of bo ...19902205530
screening method for large numbers of dye-adsorbents for enzyme purification.a method is described by means of which 96 different dye-adsorbents can be tested simultaneously for their ability to bind enzymes and to test their biospecific elution. small amounts of cell-free extract are applied to dye-adsorbents which are packed in a 96-well transplate cartridge. after biospecific elution, the amount of the eluted enzyme is tested in a microtitre plate assay. the method is illustrated by the purification of glycerol dehydrogenase (e.c., 6-phosphogluconate dehydro ...19902205614
a mutation which modifies the activity of a translational suppressor in aspergillus nidulans.a third type of translational fidelity mutation has been induced in aspergillus nidulans. the new mutation enhances growth, in suppressing conditions, of a strain containing suppressor suac109 and antisuppressor asud14 and is called alob8 for its allosuppressor activity. compared with the progenitor strain (asud14, suac109), ribosomes from the new mutant (alob8, asud14, suac109) increase misincorporation of leucine in a poly(u)-dependent homologous cell-free assay. the misreading level is mainta ...19902207157
isolation and molecular characterization of the aspergillus nidulans wa gene.the walls of aspergillus nidulans conidia contain a green pigment that protects the spores from damage by ultraviolet light. at least two genes, wa and ya, are required for pigment synthesis: ya mutants produce yellow spores, wa mutants produce white spores, and wa mutations are epistatic to ya mutations. we cloned wa by genetic complementation of the wa3 mutation with a cosmid library containing nuclear dna inserts from the wild-type strain. the wa locus was mapped to an 8.5-10.5-kilobase regio ...19902227390
chromatography and generation of specific antisera to synthetic peptides from a protective boophilus microplus antigen.four oligopeptides corresponding to predicted antigenic regions of the protective bm86 glycoprotein of the cattle tick boophilus microplus were synthesized and purified. three were conjugated to carrier proteins and antisera raised in rabbits and cows. all elicited antipeptide antibodies that recognized bm86 and recombinant derived products in western blots; however, only one produced antiserum capable of recognizing native bm86 in an indirect immunofluorescence assay. ticks fed in vitro on this ...19902229227
characterization of a glycerol kinase mutant of aspergillus niger.a glycerol-kinase-deficient mutant of aspergillus niger was isolated. genetic analysis revealed that the mutation is located on linkage group vi. the phenotype of this mutant differed from that of a glycerol kinase mutant of aspergillus nidulans in its ability to utilize dihydroxyacetone (dha). the weak growth on glycerol of the a. niger glycerol kinase mutant showed that glycerol phosphorylation is an important step in glycerol catabolism. the mutant could still grow normally on dha because of ...19902230717
nucleotide and amino acid sequences of the conidium-specific spoc1-c1d gene from aspergillus nidulans. 19902243803
the identification of mutations in aspergillus nidulans that lead to increased levels of adhii.there are at least three alcohol dehydrogenases in aspergillus nidulans. adhii has been observed in polyacrylamide gels stained for adh activity but, unlike adhi and adhiii, no physiological function has been attributed to it. this paper describes mutations that have been isolated from strains carrying a deletion in the structural gene for adhi (alca) and its adjacent positively-acting regulatory gene (alcr) that restore some ability to utilise ethanol as a carbon source. the mutations map at th ...19902245474
light is required for conidiation in aspergillus nidulans.light is necessary for asexual sporulation in aspergillus nidulans but will elicit conidiation only if irradiation occurs during a critical period of development. we show that conidiation is induced by red light and suppressed by an immediate shift to far red light. conidiation-specific gene functions switch from light-independent to light-dependent activities coincident with the expression of brla, a regulator of conidiophore development. we also show that light dependence is abolished by a mut ...19902253875
nitrogen regulation in aspergillus: are two fingers better than one?the area gene, mediating nitrogen metabolite repression in aspergillus nidulans, encodes a positive-acting regulatory protein with a single putative dna-binding 'zinc finger' which is remarkably similar to the two 'zinc fingers' of the major regulatory protein of vertebrate erythroid cells (gf-1/eryf1/nf-e1). the area-300 mutation alters the specificity of gene activation in that it elevates expression of certain structural genes whilst reducing expression of certain others. it is an 'in-frame' ...19902253884
purification, cloning, and primary structure of an enantiomer-selective amidase from brevibacterium sp. strain r312: structural evidence for genetic coupling with nitrile enantiomer-selective amidase active on several 2-aryl and 2-aryloxy propionamides was identified and purified from brevibacterium sp. strain r312. oligonucleotide probes were designed from limited peptide sequence information and were used to clone the corresponding gene, named amda. highly significant homologies were found at the amino acid level between the deduced sequence of the enantiomer-selective amidase and the sequences of known amidases such as indoleacetamide hydrolases from pseudo ...19902254253
identification of an amino acid substitution in the bena, beta-tubulin gene of aspergillus nidulans that confers thiabendazole resistance and benomyl supersensitivity.we are using molecular genetic techniques to identify sites of interaction of beta-tubulin with benzimidizole anti-microtubule agents. we have developed a marker-rescue technique for cloning mutant alleles of the bena, beta-tubulin gene of aspergillus nidulans and have used the technique to clone two mutant bena alleles, bena16 and bena19. these are the only a. nidulans alleles known to confer resistance to the benzimidazole antimicrotubule agent thiabendazole and supersensitivity to other benzi ...19902257633
heterologous gene expression by filamentous fungi: secretion of human interleukin-6 by aspergillus nidulans.expression vectors for human interleukin-6 (hil6) contain an expression cassette consisting of the aspergillus niger glaa promoter and the aspergillus nidulans argb terminator. the secretion signals were either those of glaa or that of the authentic hil6 peptide. the constructs under study were introduced into a. nidulans and a. niger by means of cotransformation. no il6 activity could be detected in the medium of a cotransformed a. niger strain, although transcripts corresponding with the il6 c ...19902258049
a translocation activating the cryptic nitrogen regulation gene areb inactivates a previously unidentified gene involved in glycerol utilisation in aspergillus nidulans.the chromosome viii translocation breakpoint of the areb-404 translocation, selected for its ability to activate the cryptic nitrogen metabolism regulatory gene areb, and the mutation glcd-100 both lead to loss of mitochondrial fad-dependent sn-glycerol-3-phosphate dehydrogenase in aspergillus nidulans. these two lesions therefore define glcd, a second gene (in addition to glcb) where mutation can result in loss of this enzyme. the glcd gene has been localised to a centromere-proximal region of ...19902259335
fungal flora associated with combine harvester wheat and sorghum dusts from egypt.107 species and 8 species varieties belonging to 44 genera were collected from combine harvester wheat and sorghum dusts (35 genera and 91 species + 4 varieties) and from the atmosphere of their hay sites (26 genera and 69 species + 4 varieties) on glucose- and cellulose-czapek's dox agar at 28 degrees c and 45 degrees c. the mycoflora of wheat and sorghum dusts were basically similar on the two types of media and the most common fungi were: alternaria alternata, aspergillus flavus, a. fumigatus ...19902266490
solubilisation of a cell wall bound invertase in aspergillus nidulans.aspergillus nidulans produces an extracellular invertase when incubated in the presence of sucrose and about half of the activity produced was found to be associated with the mycelium. sixty percent of this mycelial invertase could be solubilised by simple mechanical disruption. among the agents tested for solubilisation of invertase, proteinase k and dithiothreitol were the most effective.19902272493
molecular basis for determining the sensitivity of eucaryotes to the antimitotic drug rhizoxin.rhizoxin, an antibiotic, exhibits potent anti-mitotic activity against most eucaryotic cells including those of higher vertebrates, plants and fungi by binding to beta-tubulin. the bena gene of three independently isolated rhizoxin-resistant (rhir) mutants of aspergillus nidulans was cloned, sequenced and compared with that of the wild-type, rhizoxin-sensitive (rhis) strain. in all three rhir mutants, the aac codon for asn-100 of the bena beta-tubulin gene was altered to atc, coding for ile. seq ...19902274023
genetic analysis of amds transformants of aspergillus niger and their use in chromosome mapping.the aspergillus nidulans gene coding for acetamidase (amds) was introduced into a. niger by transformation. twelve amd+ transformants were analysed genetically. the amds inserts were located in seven different linkage groups. in each transformant the plasmid was integrated in only a single chromosome. our (non-transformed) a. niger strains do not grow on acetamide and are more resistant to fluoroacetamide than the transformants. diploids hemizygous for the amds insert have the amd+ phenotype. we ...19902274031
alcohol dehydrogenase iii in aspergillus nidulans is anaerobically induced and post-transcriptionally alcohol dehydrogenase was shown to be induced in aspergillus nidulans by periods of anaerobic stress. this alcohol dehydrogenase was shown to correspond to the previously described cryptic enzyme, alcohol dehydrogenase iii (mcknight et al. 1985), by analysis of a mutation in the structural gene of alcohol dehydrogenase iii, alcc, created by gene disruption. survival tests on agar plates showed that this enzyme is required for long-term survival under anaerobic conditions. northern blot analys ...19902274033
sequence, organization and expression of the core histone genes of aspergillus nidulans.the core histone gene family of aspergillus nidulans was characterized. the h2a, h2b and h3 genes are unique in the a. nidulans genome. in contrast there are two h4 genes, h4.1 and h4.2. as previously reported for the h2a gene (may and morris 1987) introns also interrupt the other core histone genes. the h2b gene, like the h2a gene, is interrupted by three introns, the h3 and h4.1 gene are each interrupted by two introns and the h4.2 gene contains one intron. the position of the single intron in ...19902274040
expression and secretion in aspergillus nidulans and aspergillus niger of a cell surface glycoprotein from the cattle tick, boophilus microplus, by using the fungal amds promoter system.a cell surface glycoprotein (bm86) from cells of the digestive tract of the cattle tick boophilus microplus, which has been shown to elicit a protective immunological response in vaccinated cattle, was expressed and secreted in the filamentous fungi aspergillus nidulans and aspergillus niger by using the fungal amds promoter system. the cloned gene coded for the bm86 secretory signal and all of the bm86 mature polypeptide except for the hydrophobic carboxy-terminal segment. high levels of bm86 m ...19902275533
an electrophoretic karyotype of aspergillus electrophoretic karyotype of aspergillus niger was obtained using contour-clamped homogeneous electric field (chef) gel electrophoresis. chromosome-sized dna was separated into four bands. seven of the eight linkage groups could be correlated with specific chromosomal bands. for this purpose dna preparations from seven transformant strains of a. niger each carrying the heterologous amds gene of aspergillus nidulans on a different chromosome were analysed. some of the assignments were confirme ...19902277644
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