TitleAbstractYear(sorted ascending)
development of a homologous transformation system for aspergillus parasiticus with the gene encoding nitrate reductase.the nitrate reductase structural gene (niad) and an niad mutant strain were isolated from aspergillus parasiticus and used to develop a homologous transformation system. a transformation frequency of 110 to 120 transformants per microgram linear dna was obtained with the 10.9 kb plasmid psl82, which contained the niad gene of a. parasiticus. plasmid psl82 was also capable of complementing aspergillus nidulans fgsc a691, a niad mutant, though at lower frequencies. southern hybridization analyses ...19902277647
investigation of the het genes that control heterokaryon incompatibility between members of heterokaryon-compatibility (h-c) groups a and g1 of aspergillus nidulans.a chromosome assay method was used to determine the heterokaryon compatibility relationships between strains belonging to heterokaryon-compatibility (h-c) groups a and g1 of aspergillus nidulans. a hybrid strain (rd15) was isolated following protoplast fusion of strains 65-5 (h-ca) and 7-141 (h-cg1). the morphology of rd15 was severely abnormal compared to diploid strains of a. nidulans produced from heterokaryon-compatible haploid parents. inocula of rd15 were induced to haploidize on medium co ...19902283501
the genetics of conidiophore pigmentation in aspergillus nidulans.the grey-brown pigmentation of aspergillus nidulans conidiophores depends on the functions of two 'ivory' loci. ivob codes for a developmental specific phenol oxidase, and mutants accumulate its substrate n-acetyl-6-hydroxytryptophan. ivoa mutants are unable to make this substrate. yga mutants are also poorly pigmented, and extracts require copper salts to activate both the phenol oxidase and conidial laccase. ivoa and ivob mutants partially suppress the spore colour phenotype of yga mutants. co ...19902283502
an evolutionary comparison of acinetobacter calcoaceticus trpf with trpf genes of several organisms.the deduced amino acid sequence of acinetobacter calcoaceticus n-(5'-phosphoribosyl) anthranilate isomerase (prai), which is coded by trpf, was compared with trpf of caulobacter crescentus, escherichia coli, bacillus subtilis, saccharomyces cerevisiae, neurospora crassa, and aspergillus nidulans. sixty percent of identical or similar amino acids were located in alpha/beta tim (triose-phosphate isomerase) barrels and in residues important in substrate binding and catalysis. in addition, the analy ...19902299982
the purification and characterization of 3-dehydroquinase from streptomyces coelicolor.the enzyme 3-dehydroquinase was purified over 4000-fold to homogeneity from streptomyces coelicolor. the subunit mr estimated from polyacrylamide-gel electrophoresis in the presence of sds was 16,000. the native mr estimated by gel filtration on a superose 6 column was 209,000, indicating that the enzyme is a large oligomer. the enzyme was found to be extremely thermostable. this stability, along with the structural and kinetic properties of the enzyme, suggest that it is very similar to the qui ...19902306211
how does the cell count the number of ectopic copies of a gene in the premeiotic inactivation process acting in ascobolus immersus?repeated genes, artificially introduced in ascobolus immersus by integrative transformation, are frequently inactivated during the sexual phase. inactivation is observed in about 50% of meioses if duplicated genes are at ectopic chromosomal locations, and in 90% of meioses if genes are tandemly repeated. inactivation is associated with extensive methylation of the cytosine residues of the duplicated sequences and is induced in the still haploid nuclei of the dikaryotic cell which will undergo ka ...19902311917
studies on the mycoflora of aswan high dam lake, egypt: monthly variations.fifty-one species and one variety appertaining to twenty one genera of mesophilic fungi were recovered from the monthly samples of marginal water (44 species, 1 variety and 18 genera) and submerged mud (78 species, 1 variety and 30 genera) of aswan high dam lake during the period from july 1985 to december 1986. the most common species were aspergillus fumigatus, a. flavus, a. terreus, a. niger and penicillium funiculosum. the highest fungal populations were almost detected either in october, in ...19902352135
the complete dna sequence of the mitochondrial genome of podospora anserina.the complete 94,192 bp sequence of the mitochondrial genome from race s of podospora anserina is presented (1 kb = 10(3) base pairs). three regions unique to race a are also presented bringing the size of this genome to 100,314 bp. race s contains 31 group i introns (33 in race a) and 2 group ii introns (3 in race a). analysis shows that the group i introns can be categorized according to families both with regard to secondary structure and their open reading frames. all identified genes are tra ...19902357736
transformation of the rice blast fungus magnaporthe grisea to hygromycin b resistance.low frequency, integrative transformation of three fertile hermaphroditic strains of magnaporthe grisea has been achieved using plasmid pan7-1 and cosmid pan7-2, which contain an escherichia coli hygromycin b phosphotransferase gene linked to aspergillus nidulans regulatory sequences.19902357737
nucleases in the autolysis of filamentous fungi.rnase and dnase activities were studied in seven fungi of the subdivisions ascomycotina, zygomycotina and basidiomycotina during their autolysis, and extracellular and intracellular rnase and dnase were found. rnase specific activity reached higher levels than dnase specific activity in the culture liquid and mycelial extract, except in aspergillus nidulans. generally maximal rnase specific activities were observed at the onset of autolysis in the culture liquid. in the mycelial extract an incre ...19902379813
genetic analysis of aspergillus niger: isolation of chlorate resistance mutants, their use in mitotic mapping and evidence for an eighth linkage group.this paper describes the use of chlorate resistant mutants in genetic analysis of aspergillus niger. the isolated mutants could be divided into three phenotypic classes on the basis of nitrogen utilization. these were designated nia, nir and cnx as for aspergillus nidulans. all mutations were recessive to their wild-type allele in heterokaryons as well as in heterozygous diploids. the mutations belong to nine different complementation groups. in addition a complex overlapping complementation gro ...19902381424
localization of pyruvate carboxylase in organic acid-producing aspergillus strains.the localization of pyruvate carboxylase (cytosolic or mitochondrial) was studied in nine different aspergillus species (14 strains). in some species (a. aculeatus, a. flavus, a. foetidus, a. nidulans, a. ochraceus, and a. sojae), the pyruvate carboxylase activity could be detected only in the cytosolic fraction of the cells. pyruvate carboxylase has been found only in the mitochondrial fraction of two strains of aspergillus wentii. in aspergillus oryzae and in five strains of aspergillus niger, ...19902383004
high-efficiency transformation system for the biocontrol agents, trichoderma spp.we have developed an efficient transformation system based on the use of polyethylene glycol and cacl2 for the biocontrol agents, trichoderma spp. transformation was obtained with the plasmid pan7-1, carrying a bacterial hygromycin-resistance gene as a selectable marker, under the control of aspergillus nidulans heterologous expression signals. the system described here yielded 200-800 transformants per microgram of dna. transformants contained several copies of the plasmid integrated into their ...19902388561
survey of the mycoflora and mycotoxins of cotton seeds and cotton seed products in egypt.thirty-nine species and 16 fungal genera were isolated from egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-czapek's agar medium incubated at 28 degrees c. aspergillus was the most frequent genus and it emerged in 87-100% of the samples contributing 70-98% of total fungi in the three substrates tested. the most common species were a. niger, a. flavus, a. fumigatus, a. terreus and rhizopus stolonifer; a. niger, a. fumigatus and penicillium corylophilum; and a. niger, a. ...19902388680
cloning and analysis of beta-tubulin gene from a protoctist.we have isolated and characterized by restriction endonuclease mapping, transcription pattern, and dna sequencing a beta-tubulin gene from the coenocytic freshwater protoctist, achlya klebsiana. the gene is intronless and has a single open reading frame that encodes a 444-amino acid residue polypeptide of mr 49,856. the protein shows a high degree of homology to other beta-tubulins, 85% identity to human beta-tubulin and 89% identity to beta-tubulin of the sporozoan (also a protoctist) plasmodiu ...19902394720
homologous transformation of cephalosporium acremonium with the nitrate reductase-encoding gene (niad).we report the development of a homologous transformation system for cephalosporium acremonium using the niad gene of the nitrate assimilation (na) pathway. mutants in the na pathway were selected on the basis of chlorate resistance by conventional means. screening procedures were developed to differentiate between nitrate reductase apoprotein structural gene mutants (niad) and molybdenum cofactor gene mutants (cnx) as wt c. acremonium, unlike most filamentous fungi, fails to grow on minimal medi ...19902401400
the aspergillus nidulans npea locus consists of three contiguous genes required for penicillin biosynthesis.clones of aspergillus nidulans genomic dna spanning 20 kb have been isolated and shown by a combination of classical and molecular genetic means to represent the npea locus, previously found to be one of four loci (npea, npeb, npec and nped) involved in the synthesis of penicillin. as well as containing the gene encoding the second enzyme for penicillin biosynthesis, namely isopenicillin n synthetase (ipns) (designated ipna), our results show that these clones (psta200, psta201 and psta207) cont ...19902403928
selective overexpression of the qute gene encoding catabolic 3-dehydroquinase in multicopy transformants of aspergillus nidulans.the three enzymes necessary to catabolize quinate to protocatechuate are inducible by quinic acid, and transcription of their corresponding genes is controlled by the action of a positively acting activator gene and a negatively acting repressor gene. transformed strains of aspergillus nidulans containing multiple copies of the activator gene (quta) but single copies of the other qut genes retain normal regulation of the gene cluster and do not show any overexpression of the three quinic acid ca ...19902405841
hen egg white lysozyme expressed in, and secreted from, aspergillus niger is correctly processed and folded.we transformed aspergillus niger with the full length cdna gene encoding hen egg-white lysozyme (hewl) and its secretion signal sequence. lysozyme levels up to 12 mg/l were secreted when expression was controlled by the a. awamori glucoamylase (gam) promoter and 1 mg/l when controlled by the a. nidulans glyceraldehyde-3-phosphate dehydrogenase (gpd) promoter. n-terminal sequence analysis of the recombinant protein indicated that the signal peptide was correctly processed by the a. niger secretor ...19901366900
efficient kex2-like processing of a glucoamylase-interleukin-6 fusion protein by aspergillus nidulans and secretion of mature interleukin-6.we have designed an expression vector for the secretion of human interleukin-6 (hil-6) in which the mature protein is fused through a spacer peptide, containing a kex-2 like protein processing signal, to the entire aspergillus niger glucoamylase (glaa) gene. transformation of aspergillus nidulans with this vector results in fungal strains secreting equimolar amounts of the glucoamylase and il-6 proteins. the kex2-type processing signal, lys-arg, is recognized and cleaved efficiently by an enzyme ...19911367012
the ethanol utilization regulon of aspergillus nidulans: the alca-alcr system as a tool for the expression of recombinant proteins. 19911367013
expression of heterologous proteins in aspergillus.filamentous fungi, in particular those of the genus aspergillus have been well exploited for their ability to produce high levels of extracellular proteins in an inexpensive manner. since many human proteins with the potential to be used therapeutically are secreted and require post-translational modification for biological activity, eukaryotic expression-secretion systems have been targeted for development. recent developments in dna-mediated transformation systems have allowed the utilization ...19911367014
identification and expression of the acv synthetase gene.the gene coding for acv synthetase has recently been identified and cloned. analysis of its structure and expression, along with similar studies of other genes involved in beta-lactam biosynthesis, should lead to a better understanding of the molecular basis of regulation of the pathway and the possibility of modifying yield and diversity of fungal antibiotics.19911367017
construction and physiological characterization of glyceraldehyde-3-phosphate dehydrogenase overproducing transformants of aspergillus nidulans.the construction and characterization of glyceraldehyde-3-phosphate-dehydrogenase (gpd) overproducing transformants of aspergillus nidulans and their behaviour in acetate-limited continuous cultures and glucose-grown batch cultures are described. the a. nidulans acetamidase deletion strain mh1277 was transformed with the homologous gpda gene on a vector with the homologous acetamidase-gene (amds) as a selection marker. transformant a1 contains about nine integrated copies of the gpda gene, and s ...19911367201
integrative transformation of the ascomycete podospora anserina: identification of the mating-type locus on chromosome vii of electrophoretically separated chromosomes.protoplasts of wild-type strain s and a long-lived extrachromosomal mutant (al2) of the ascomycete podospora anserina were transformed using a plasmid (pan7-1) which contains the hygromycin b phosphotransferase gene (hph) of escherichia coli under the control of aspergillus nidulans regulatory sequences. after optimizing the transformation procedure, transformation efficiencies of 15-21 transformants/micrograms plasmid dna were obtained. using a second selectable vector (pbt3), which contains th ...19911367277
intracellular and extracellular production of proteins in aspergillus under the control of expression signals of the highly expressed aspergillus nidulans gpda gene.the expression in aspergillus is described of genes, coding for intracellular and extracellular proteins controlled by the promoter region of the constitutively and efficiently expressed glyceraldehyde-3-phosphate dehydrogenase gene (gpda) of aspergillus nidulans. both the homologous gpda and the heterologous escherichia coli beta-galactosidase (lacz) and beta-glucuronidase (uida) genes could be expressed intracellularly at levels as high as 10-25% of total soluble protein. efficient extracellul ...19911367494
molecular characterization and functional analysis in aspergillus nidulans of the 5'-region of the penicillium chrysogenum isopenicillin n synthetase gene.the isopenicillin n synthetase gene (pcbc) was isolated from a genomic library of penicillium chrysogenum bc39813, a penicillin production strain. the nucleotide sequence, including 555 bp upstream of the translation start site was determined. various deletions within the pcbc 5'-region were constructed and linked to the escherichia coli lacz gene. an aspergillus nidulans argb strain was transformed with dna of these constructions. the region essential for promoter function could be localized be ...19911367495
cloning of the nitrate-nitrite reductase gene cluster of penicillium chrysogenum and use of the niad gene as a homologous selection marker.a new homologous transformation system for the filamentous fungus penicillium chrysogenum is described. the system is based on complementation of niad mutants using the nitrate reductase structural gene (niad) of p. chrysogenum. spontaneous niad mutants were identified after selection for chlorate resistance, in growth tests and subsequent complementation with the niad gene of aspergillus oryzae. the p. chrysogenum niad gene was isolated from a genomic library using the aspergillus nidulans niad ...19911367546
codon usage in aspergillus nidulans.synonymous codon usage in genes from the ascomycete (filamentous) fungus aspergillus nidulans has been investigated. a total of 45 gene sequences has been analysed. multivariate statistical analysis has been used to identify a single major trend among genes. at one end of this trend are lowly expressed genes, whereas at the other extreme lie genes known or expected to be highly expressed. the major trend is from nearly random codon usage (in the lowly expressed genes) to codon usage that is high ...19911745237
heterologous expression of the aspergillus nidulans regulatory gene nira in fusarium oxysporum.we have isolated strains of fusarium oxysporum carrying mutations conferring a phenotype characteristic of a loss of function in the regulatory gene of nitrate assimilation (nira in aspergillus nidulans, nit-4 in neurospora crassa). one of these nir- mutants was successfully transformed with a plasmid containing the nira gene of a. nidulans. the nitrate reductase of the transformants is still inducible, although the maximum activity is lower than in the wild type. single and multiple integration ...19911756977
isolation and nucleotide sequence of the ribosomal protein s16-encoding gene from aspergillus nidulans.a genomic clone has been isolated from aspergillus nidulans which is homologous to the ribosomal (r) protein s16-encoding gene of saccharomyces cerevisiae (s16a) and the r-protein s19-encoding gene of rat (s19). the amino acid (aa) sequences, deduced from nucleotide (nt) sequence analysis, show that in both cases more than 63% of the aa are conserved. the proposed a. nidulans r-protein s16 gene (rps16) differs from that of s. cerevisiae in that it occurs as a single copy in the haploid genome (r ...19911761226
regulatory functions of calmodulin.calmodulin is a ca2+ binding protein present in all eukaryotic cells that serves as the primary intracellular receptor for ca2+. this 148 amino acid protein is involved in activation of more than 20 enzymes which mediate a wide variety of physiological processes. many of these enzymes are inhibited in an intramolecular manner and the ca(2+)-calmodulin complex relieves this inhibition. calmodulin is essential for life as disruption of the gene in genetically tractable organisms is lethal. this pr ...19911763137
the uay positive control gene of aspergillus nidulans: fine structure, isolation of constitutive mutants and reversion patterns.the product of the uay gene of aspergillus nidulans is necessary for the expression of at least eight genes coding for enzymes and permeases of the purine utilisation pathway. a detailed fine structure map has been constructed of this gene involving 13 presumed point mutations and eight deletions. gene conversion of these deletions was demonstrated. a technique was devised to select for constitutive mutations and two were obtained which map within the uay gene. we have shown that the most centro ...19911766434
molecular cloning of the uay regulatory gene of aspergillus nidulans reveals a favoured region for dna insertions.the cloning of the positive regulatory gene, uay, which mediates uric acid induction of enzymes and permeases of the purine degradation pathway in the fungus aspergillus nidulans is described here. the 4 kb uay transcript is constitutively synthesised, it is not repressed by ammonia and its transcription does not require the area wide-domain transcription factor. we have determined that four deletions, which have been genetically characterised, are confined to a segment of 0.9 kb. two other dele ...19911766435
isolation of nuclei from aspergillus nidulans protoplasts.intact nuclei were isolated from the protoplasts of the filamentous fungus aspergillus nidulans. the large amounts of protoplasts required for such nuclear preparations were produced from young mycelia grown in liquid culture. for final purification of the crude nuclear fraction, a nycodenz density-gradient centrifugation was applied. the resulting nuclei were of good purity and morphological state, as demonstrated by fluorescence microscopy and electronmicroscopy. the weight ratio of dna:rna:pr ...19911769520
the fission yeast gamma-tubulin is essential for mitosis and is localized at microtubule organizing centers.gamma-tubulin exists in fission yeast as the product of an essential gene, encoding a 446 amino acid protein that is 77.3% identical to aspergillus nidulans gamma-tubulin. the gene disruption caused cell lethality, displaying condensed, undivided chromosomes with aberrant spindle structures. anti-gamma-tubulin staining showed that gamma-tubulin is located, throughout the wild-type cell cycle, at the spindle pole bodies (spbs), indicating that gamma-tubulin associates with interphase spb in the a ...19911770000
bima encodes a member of the tetratricopeptide repeat family of proteins and is required for the completion of mitosis in aspergillus nidulans.the recessive, temperature-sensitive bima1 mutation of aspergillus nidulans blocks nuclei in metaphase at restrictive temperature. to determine whether the bima product is essential, integrative transformation was used to create a mutation in the bima gene. the mutation was maintained in a heterokaryon and the phenotype of spores produced by the heterokaryon was analyzed. molecular disruption of the wild-type bima gene is recessive in the heterokaryon and causes a metaphase block, demonstrating ...19911770001
relationships between phosphatidylcholine content, chitin synthesis, growth, and morphology of aspergillus nidulans choc.the phosphatidylcholine (pc) content of aspergillus nidulans choc was varied by growing the auxotroph in medium containing various concentrations of choline chloride. direct linear correlations were observed between pc content and in vivo chitin synthase activity, between in vivo chitin synthase activity and mean hyphal extension rate, and between mean hyphal extension rate and hyphal growth unit length; hyphal growth unit length is a measure of hyphal branching. further, there was a correlation ...19911778430
the development of aspergillus niger var. awamori as a host for the expression and secretion of heterologous gene products. 19911783197
altered expression of the steroid bioconverting pathway in pan 7-1 transformants of cochliobolus lunatus.the filamentous fungus c. lunatus converts progesterone mainly to its 11 beta-hydroxy derivative. c. lunatus transformed with the plasmid pan 7-1, which contains the e. coli hph gene expressed under the control of the a. nidulans gpd and trpc expression signals, lacks this activity, but exhibits acetyl side chain degradation of progesterone through the reaction scheme progesterone----20 beta-hydroxy-progesterone----delta 4-androstene-3,17-dione---- testolactone + testosterone. the main part of t ...19911807829
mycofloral changes and aflatoxin contamination in stored chickpea seeds.chickpea seeds entering store carry a microflora of 'field' and 'storage' fungi. field fungi gradually disappear and storage fungi then predominate. these fungi especially aspergillus flavus, a. niger, a. nidulans, a. ochraceus and penicillium spp. grow vigorously and initiate grain spoilage and aflatoxin elaboration. the shift in mycofloral spectrum was more rapid in seeds stored in jute bags than those stored in metal bins. moisture content and aflatoxin contamination in seeds of jute bags was ...19911812019
role of the cell-cycle-regulated nima protein kinase during g2 and mitosis: evidence for two pathways of mitotic regulation. 19911819506
kinesin-like proteins of aspergillus nidulans. 19911819513
heterologous expression and regulation of the neurospora crassa nit-4 pathway-specific regulatory gene for nitrate assimilation in aspergillus nidulans.the nira gene of aspergillus nidulans and the nit-4 gene of neurospora crassa appear to be equivalent pathway-specific regulatory genes which mediate nitrate induction of nitrate reductase and nitrite reductase (nr and nir) activities. we have transformed the nit-4 wild-type (wt) gene into the a. nidulans loss-of-function (pleiotropic negative) nira 1 mutant strain. the nit-4 gene was found to complement the nira 1 mutation, thus permitting the nira 1 mutant strain to grow on nitrate or nitrite ...19911829047
[exogenous allergic alveolitis in tobacco industry workers]. 19911831935
molecular organisation of the malate synthase genes of aspergillus nidulans and neurospora crassa.the sequencing and comparison of the genes encoding the glyoxylate bypass enzyme malate synthase of aspergillus nidulans (acue) and neurospora crassa (acu-9) are presented. the predicted amino acid sequences of the a. nidulans and n. crassa enzymes are 538 and 542 residues respectively and the proteins are 87% homologous. in fungi, the malate synthase proteins are located in glyoxysomes and the deduced acue and acu-9 proteins both contain a c-terminal s-k-l sequence, which has been implicated in ...19911832736
sequence of the nuclear atp synthase subunit 9 gene of podospora anserina: lack of similarity to the mitochondrial genome.the nuclear gene coding for the mitochondrial subunit 9 of the f0f1-atp synthase complex was isolated from a genomic library of podospora anserina. nucleotide sequencing revealed an open reading frame capable to code for 144 amino acids including an amino-terminal pre-sequence of 63 amino acid residues for mitochondrial import of the pre-proteolipid. the p. anserina proteolipid shows extensive sequence identity with the corresponding gene products of the related filamentous fungi neurospora cras ...19911834355
cloning and molecular characterization of the acetamidase-encoding gene (amds) from aspergillus oryzae.we have isolated an acetamidase-encoding gene (amds) from aspergillus oryzae by heterologous hybridization using the corresponding aspergillus nidulans gene as a probe. the gene is located on a 3.5-kb saci fragment and its nucleotide (nt) sequence was determined. compared with the a. nidulans amds gene, the coding region of a. oryzae gene consists of seven exons interrupted by six introns and encodes 545 amino acid (aa) residues. the deduced aa sequence has a high degree of homology with that of ...19911840550
nit-4, a pathway-specific regulatory gene of neurospora crassa, encodes a protein with a putative binuclear zinc dna-binding domain.nit-4, a pathway-specific regulatory gene in the nitrogen circuit of neurospora crassa, is required for the expression of nit-3 and nit-6, the structural genes which encode nitrate and nitrite reductase, respectively. the complete nucleotide sequence of the nit-4 gene has been determined. the predicted nit4 protein contains 1,090 amino acids and appears to possess a single zn(ii)2cys6 binuclear-type zinc finger, which may mediate dna binding. site-directed mutagenesis studies demonstrated that c ...19911840634
temporal and spatial controls of aspergillus development.the mechanisms regulating elaboration of the multicellular asexual reproductive apparatus, the conidiophore, of the filamentous ascomycete aspergillus nidulans provide a model for the control of fungal development. recent advances have been made on three fronts. first, new physical and chemical signals have been discovered that control commitment of cells to the conidiation pathway. second, positively acting developmental regulatory genes have been cloned and characterized. in addition, evidence ...19911840892
domain structure and interaction within the pentafunctional arom polypeptide.the arom locus of aspergillus nidulans specifies a pentafunctional polypeptide catalysing five consecutive steps leading to the production of 5-enolpyruvylshikimate 3-phosphate in the shikimate pathway. aided by oligonucleotide-mediated site-directed mutagenesis, the whole arom locus and various overlapping subfragments from within it have been fused to the powerful hybrid trc promoter in the escherichia coli plasmid pkk233-2. expression of these subfragments in appropriate aro mutants of e. col ...19911849480
polyethylene glycol-induced internalization of bacteria into fungal protoplasts: electron microscopic study and optimization of experimental conditions.we studied the mechanism of internalization of escherichia coli into saccharomyces cerevisiae induced by polyethylene glycol (peg) and optimized the experimental conditions. transmission electron microscope studies revealed that the principal factor involved in the internalization was the degree of cell aggregation attained. internalization occurred mainly by an endocytosis-like mechanism and took place during the elimination of peg. the optimum conditions were to treat a mixed pellet of both mi ...19911854204
cell biology. abg of microtubule assembly. 19911865902
activation of the nima protein kinase plays a unique role during mitosis that cannot be bypassed by absence of the bime checkpoint.mutation of nima reversibly arrests cells in late g2 and nima overexpression promotes premature mitosis. here we demonstrate that the product of nima (designated nima) has protein kinase activity that can phosphorylate beta-casein but not histone proteins. nima kinase activity is cell cycle regulated being 20-fold higher at mitosis when compared to s-phase arrested cells. nima activation is normally required in g2 to initiate chromosome condensation, to nucleate spindle pole body microtubules, a ...19911868838
characterization of interspecific hybrids within the aspergillus nidulans group by isoenzyme analysis.a comparison of interspecific hybrids within the aspergillus nidulans species group was made by isoenzyme analysis. the gel electrophoretic patterns of the parental species were distinct for most of the enzymes tested. the hybrids were distinguishable from their parents by isoenzyme patterns. the appearance of novel bands in all the interspecific hybrids indicated that nuclear fusion could have occurred. in most hybrids the appearance of the parental bands showed nonpreferential, partial chromos ...19911878817
antisuppressor mutations reduce misreading of the genetic code in aspergillus nidulans.antisuppressor mutations were isolated in a strain containing the omnipotent suppressor suac109. the antisuppressors reduce the activity of translational suppressors in vivo and counteract most aspects of the pleiotropic phenotype associated with the suac and the suaa suppressor mutations. using an homologous system for cell-free translation, we have measured translational accuracy in two antisuppressor strains with the genotype suac109 and either the asub11 or the asud14 antisuppressor mutation ...19911878998
identification of a telomeric fragment from the right arm of chromosome iii of aspergillus nidulans.a minimum of 11 bands hybridising to an oligonucleotide complementary to the putative telomeric repeat sequence (ttaggg)n was visible in a southern blot of ecori-digested aspergillus nidulans genomic dna. all 11 were sensitive to bal 31 exonuclease digestion, consistent with telomeric locations. blots of dna from aneuploid strains deleted for a dispensable, extreme distal region on the right arm of chromosome iii lack a 1.3-kb ecori band, indicating that this fragment is located at or near the c ...19911884987
unusual metabolism of the yeast actin amino this paper we have examined the post-translational modifications of the nh2 terminus of actin from the yeast saccharomyces cerevisiae. like actins examined previously, this actin contains an acetylated nh2 terminus. actins in other organisms undergo a unique post-translational processing event in which the initial amino acid(s) are removed by an actin-specific processing enzyme in an acetylation-dependent reaction. this is defined as actin processing. in yeast, actin retains its initiator met ...19911885608
genetic transformation of auxotrophic mutants of the filamentous yeast trichosporon cutaneum using homologous and heterologous marker genes.a transformation system for the filamentous yeast trichosporon cutaneum based on auxotrophic markers is presented and techniques for the induction, isolation and characterization of mutants are described. a number of auxotrophic mutants were isolated and characterized by using biosynthetic precursors and/or inhibitors. a mutant unable to grow in the presence of ornithine could be complemented successfully by spheroplast transformation experiments using the cloned aspergillus nidulans ornithine t ...19911897316
isolation and developmentally regulated expression of an aspergillus nidulans phenol oxidase-encoding gene, ivob.ivory (ivo) mutants of aspergillus nidulans lack conidiophore pigmentation. we have cloned ivob which codes for a conidiophore-specific phenol oxidase (ahtase) via the adjacent selectable ured gene. gene-library transformants of a ured4 strain proved defective for the vector, but we recovered both ured and ivob from a lambda library of transformant dna. the ivob transcription unit was localized to a sali-xbai 3-kb fragment and its 5' end was located by hybridization with an oligodeoxyribonucleot ...19911901560
mutations in the small subunit of cyanobacterial ribulose-bisphosphate carboxylase/oxygenase that modulate interactions with large the cyanobacterium anacystis nidulans (synechococcus pcc6301), ribulose 1,5-bisphosphate carboxylase/oxygenase (rbu-p2 carboxylase) is composed of eight large subunits and eight small subunits. there are three regions of the small subunit that contain amino acids that are conserved throughout evolution, from bacteria to higher plants. since the function of the small subunit is not fully understood, site-directed mutagenesis was performed on highly conserved residues in the first and second co ...19911902220
gamma-tubulin is present in drosophila melanogaster and homo sapiens and is associated with the centrosome.the mipa gene of a. nidulans encodes a newly discovered member of the tubulin superfamily of proteins, gamma-tubulin. in a. nidulans, gamma-tubulin is essential for nuclear division and microtubule assembly and is associated with the spindle pole body, the fungal microtubule organizing center. by low stringency hybridizations we have cloned cdnas from d. melanogaster and h. sapiens, the predicted products of which share more than 66% amino acid identity with a. nidulans gamma-tubulin. gamma-tubu ...19911904010
isolation and characterisation of nuv11, a mutation affecting meiotic and mitotic recombination in aspergillus nidulans.a mutant of aspergillus nidulans, designated nuv11, has been isolated as hypersensitive to the monofunctional alkylating agent mnng and the quasi-uv-mimetic mutagen 4-nqo. the mutation was recessive, resulting from mutation of a single gene which mapped to chromosome iv, and was non-allelic to the previously characterised repair-deficient mutations uvsb and uvsh which are also located on this linkage group. the nuv11 mutation results in slow growth, deficient intragenic and intergenic meiotic re ...19911909187
parallel activation of the nima and p34cdc2 cell cycle-regulated protein kinases is required to initiate mitosis in a. nidulans.we show that in aspergillus nidulans, p34cdc2 tyrosine dephosphorylation accompanies activation of p34cdc2 as an h1 kinase at mitosis. however, the nima5 mutation arrests cells in g2 with p34cdc2 tyrosine dephosphorylated and fully active as an h1 kinase. activation of nima is therefore not required for p34cdc2 activation. furthermore, mutation of nimt, which encodes a protein with 50% similarity to fission yeast cdc25, causes a g2 arrest and prevents tyrosine dephosphorylation of p34cdc2 but do ...19911913824
cloning and nucleotide sequence of the genomic ribonuclease t2 gene (rntb) from aspergillus oryzae.using synthetic oligonucleotide probes, we have cloned a genomic dna sequence encoding a ribonuclease (rnase) t2 gene (rntb) from aspergillus oryzae on a 4.8 kb hindiii fragment. dna sequence analysis of the rnase t2 revealed the following: (1) the gene is arranged as five exons and four introns; (2) the deduced amino acid sequence contains 239 amino acid residues of the mature enzyme. in addition, there exist 17 amino acid residues thought to be a signal peptide sequence at the n-terminus and 2 ...19911913876
a twin-reporter vector for simultaneous analysis of expression signals of divergently transcribed, contiguous genes in filamentous analyze the promoter region(s) of divergently transcribed fungal genes, a twin-reporter vector was constructed. this vector contains two divergently oriented reported genes, encoding escherichia coli beta-glucuronidase (uida) and e. coli beta-galactosidase (lacz). terminator regions of the aspergillus nidulans nitrate and nitrite reductase-encoding genes, niad and niia, respectively, have been cloned 3' to the reporter genes to ensure proficient transcription termination of the reporter genes ...19911916271
structure and evolution of 5s rrna genes and pseudogenes in the genus aspergillus.we have cloned and determined the nucleotide sequence of 18 dna fragments hybridizing to 5s rrna from two aspergillus species--a. wentii and a. awamori. four of the analyzed sequences were pseudogenes. the gene sequences of these two species were very similar and differed from aspergillus nidulans at both constant and microheterogeneous sites.19911920453
pulsed field gel electrophoresis reveals chromosome length differences between strains of cladosporium fulvum (syn. fulvia fulva).methods are described for the electrophoretic separation of chromosome-sized dna molecules from the fungal tomato pathogen cladosporium fulvum (syn. fulvia fulva). using a hexagonal electrode array and switching times of 75 min at 45 v for 14 days, nine bands could be resolved. by comparison with co-electrophoresed aspergillus nidulans chromosomal dna (which was resolved into seven bands), the sizes of the c. fulvum bands are estimated to be between 1.9 mb and 5.4 mb. the two largest bands are b ...19911921976
analysis of the crea gene, a regulator of carbon catabolite repression in aspergillus nidulans.the complete nucleotide sequence derived from a genomic clone and two cdna clones of the crea gene of aspergillus nidulans is presented. the gene contains no introns. the derived polypeptide of 415 amino acids contains two zinc fingers of the c2h2 class, frequent s(t)pxx motifs, and an alanine-rich region indicative of a dna-binding repressor protein. the amino acid sequence of the zinc finger region has 84% similarity to the zinc finger region of mig1, a protein involved in carbon catabolite re ...19911922072
nira, the pathway-specific regulatory gene of nitrate assimilation in aspergillus nidulans, encodes a putative gal4-type zinc finger protein and contains four introns in highly conserved regions.the nucleotide sequence of nira, mediating nitrate induction in aspergillus nidulans, has been determined. alignment of the cdna and the genomic dna sequence indicates that the gene contains four introns and encodes a protein of 892 amino acids. the deduced nira protein displays all characteristics of a transcriptional activator. a putative double-stranded dna-binding domain in the amino-terminal part comprises six cysteine residues, characteristic for the gal4 family of zinc finger proteins. an ...19911922075
genome analysis of imperfect fungi: electrophoretic karyotyping and characterization of the nuclear gene coding for glyceraldehyde-3-phosphate dehydrogenase (gpd) of curvularia lunata.the gene coding for glyceraldehyde-3-phosphate dehydrogenase (gpd) has been isolated from a genomic library of the filamentous fungus curvularia lunata. the coding region of this gene consists of 1014 nucleotides and is interrupted by four introns. the gpd gene product shows a high degree of sequence identity with the corresponding proteins of various species belonging to both taxonomically related (e.g., aspergillus nidulans), as well as more divergent, taxa. using contour-clamped homogeneous e ...19911934112
hygromycin- and paromomycin-resistant mutants of aspergillus nidulans alter translational fidelity.mutants of aspergillus nidulans resistant to the aminoglycoside antibiotics paromomycin and hygromycin b have been isolated and their growth characteristics are described here. most paromomycin mutants were cross-resistant to hygromycin and geneticin. all the hygromycin-resistant mutants were slightly cross-resistant to geneticin. out of the 15 mutants tested 14 had drug-resistant ribosomes in vitro and all 12 of those investigated further had reduced levels of translational misreading. five new ...19911934127
cloning, sequencing and expression of the schwanniomyces occidentalis nadp-dependent glutamate dehydrogenase gene.the cloned nadp-specific glutamate dehydrogenase (gdh) genes of aspergillus nidulans (gdha) and neurospora crassa (am) have been shown to hybridize under reduced stringency conditions to genomic sequences of the yeast schwanniomyces occidentalis. using 5' and 3' gene-specific probes, a unique 5.1 kb bcli restriction fragment that encompasses the entire schwanniomyces sequence has been identified. a recombinant clone bearing the unique bcli fragment has been isolated from a pool of enriched clone ...19911934128
structure of the aspergillus niger pela gene and its expression in aspergillus niger and aspergillus nidulans.aspergillus niger pectin lyases are encoded by a multigene family. the complete nucleotide sequence of the pectin lyase pla-encoding gene pela has been determined. comparison of the deduced amino acid sequence with the deduced amino acid sequence of the other characterized pectin lyase, pld, shows that the proteins share 69% amino acid identity. when grown on media with pectin as the sole carbon source, a. niger transformants containing multiple copies of the pela gene show raised mrna levels an ...19911934134
transformation of aspergillus terreus with the hygromycin b resistance marker from escherichia coli.aspergillus terreus was transformed to hygromycin b resistance using a bacterial resistance gene under the control of aspergillus nidulans regulatory sequences. southern hybridization of transformants indicated that in most of the cases the vector dna was integrated into the recipient chromosome in the form of tandem arrays. transformants were mitotically stable in both selective and non-selective medium and retained their capacity to produce xylanase or glucoamylase activities.19911936947
the tubb alpha-tubulin gene is essential for sexual development in aspergillus nidulans.the filamentous fungus aspergillus nidulans has two genes encoding alpha-tubulin, tuba and tubb. mutational analysis of tuba has demonstrated that the tuba gene is essential for mitosis and nuclear migration. in this study we have deleted the tubb gene by replacing it with a selectable marker and have named this new allele tubb delta. the results demonstrate that the tubb gene is not required for vegetative growth or asexual reproduction, nor is it required for the initiation or early stages of ...19911936991
analysis of aspergillus nidulans conidial antigens and their prevalence in other aspergillus species.aspergillus nidulans is an ascomycetous fungus that reproduces asexually by forming multicellular conidiophores and uninucleate spores called conidia. these elements constitute the main vehicle for the transmission of this and other pathogenic aspergillus species and are the starting point of the different forms of aspergillosis. in order to use a. nidulans as a potential source of useful antigens for the immunodiagnosis of these diseases, we have examined the total protein composition of conidi ...19911937806
the influence of solvent stress on mms-induced genetic change in saccharomyces cerevisiae.mms induced mitotic recombination but not mitotic chromosome loss when tested in pure form in strain d61.m of saccharomyces cerevisiae, confirming previous results of albertini (1991), whereas in aspergillus nidulans it also induced chromosomal malsegregation in addition to mitotic recombination (käfer, 1988). however, induction of mitotic chromosome loss was observed in combination with strong inducers of chromosome loss such as the aprotic polar solvents ethyl acetate and to a lesser extent me ...19911944341
cell biology. never-in-mitosis in mitosis. 19911944528
aspergillus nidulans weta activates spore-specific gene expression.the aspergillus nidulans weta gene is required for synthesis of cell wall layers that make asexual spores (conidia) impermeable. in weta mutant strains, conidia take up water and autolyze rather than undergoing the final stages of maturation. weta is activated during conidiogenesis by sequential expression of the brla and abaa regulatory genes. to determine whether weta regulates expression of other sporulation-specific genes, its coding region was fused to a nutritionally regulated promoter tha ...19911986246
crna encodes a nitrate transporter in aspergillus nidulans.the nucleotide sequence of the aspergillus nidulans crna gene for the transport of the anion nitrate has been determined. the crna gene specifies a predicted polypeptide of 483 amino acids (molecular weight 51,769). a hydropathy plot suggests that this polypeptide has 10 membrane-spanning helices with an extensive hydrophilic region between helices six and seven. no striking homology was observed between the crna protein and other reported membrane proteins of either prokaryotic or eukaryotic or ...19911986367
molecular cloning and functional characterization of the pathway-specific regulatory gene nira, which controls nitrate assimilation in aspergillus nidulans.we have cloned an 11-kbp segment of the genomic dna of aspergillus nidulans which complements mutations in nira, the pathway-specific regulatory gene of the nitrate assimilation pathway. gene disruption in the corresponding region of the nuclear dna leads to a phenotype and a gene complementation pattern indistinguishable from that observed in known noninducible nira mutants. transformation studies with subclones of the 11-kbp genomic segment showed that a nonreverting null mutation nira87, maps ...19911990284
cloning and characterization of an amidase gene from rhodococcus species n-774 and its expression in escherichia coli.for investigation of an unknown open reading frame which is present upstream of the nitrile hydratase (nhase) gene from rhodococcus sp. n-774, a longer dna fragment covering the entire gene was cloned in escherichia coli. nucleotide sequencing and detailed subcloning experiments predicted a single open reading frame consisting of 521 amino acid residues of mr 54,671. the amino acid sequence, especially its nh2-terminal portion, showed significant homology with those of indoleacetamide hydrolases ...19912001397
an autonomously replicating plasmid transforms aspergillus nidulans at high frequency.from an unstable aspergillus nidulans colony, resulting from transformation with an a. nidulans gene bank, a plasmid was reisolated which transformed a. nidulans at a frequency of 20,000 transformants per 10(6) protoplasts at near saturation levels of transforming dna. this represents a 250-fold enhancement of transformation efficiency over that found for typical integrative vectors such as pilj16, the plasmid used in gene bank constructions. the plasmid, designated arp1, is 11.5 kb in size, and ...19912013411
ecotoxicological aspects of aspergilli present in the phylloplane of stored leaves of chewing tobacco (nicotiana tobaccum).nine different species of aspergillus were isolated from the phylloplane of stored chewing tobacco (nicotiana tobaccum) of different ages. the maximum number of species were isolated from 12 and 18 month old leaves. a. ruber, a. ochraceus, a. flavus and a. nidulans were usually associated with older leaves while a. niger, a. fumigatus and a. flavus were isolated from 6 month old leaves. approximately 18% of aspergilli were found to be mycotoxigenic. sterigmatocystin was produced by three differe ...19912014047
regulation of invertase in aspergillus nidulans: effect of different carbon sources.aspergillus nidulans produces an extracellular beta-d-fructofuranoside fructohydrolase (invertase) when grown on a medium containing the beta-fructofuranosides sucrose or raffinose, indicating that synthesis is subject to induction by the substrate. on a growth medium containing sucrose, production was maximal at 15 h in cultures incubated at 28 c degrees. after this time the level of detectable invertase in the cultures declined. a proportion of the enzyme was secreted during the linear growth ...19912016586
isolation and nucleotide sequence of the aspergillus restrictus gene coding for the ribonucleolytic toxin restrictocin and its expression in aspergillus nidulans: the leader sequence protects producing strains from suicide.we describe the cloning and characterization of the gene coding for the ribotoxin restrictocin, from aspergillus restrictus (gene res, embl accession number x56176). this toxin is a potent inhibitor of protein synthesis in eucaryotes and is of potential interest as a component of immunotoxins. to analyze the mechanism of self-protection in the producing organism, the res gene was cloned into the vector pfb39 and introduced into aspergillus nidulans. the secretion of active restrictocin from tran ...19912020539
glycerol catabolism in aspergillus nidulans.glycerol is catabolized in aspergillus nidulans by glycerol kinase and a mitochondrial fad-dependent sn-glycerol 3-phosphate dehydrogenase. the levels of both enzymes are controlled by carbon catabolite repression and by specific induction. biochemical and genetical analyses show that dihydroxyacetone and d-glyceraldehyde are converted into glycerol and then catabolized by the same pathway. d-glyceraldehyde can be reduced by nadp(+)-dependent glycerol dehydrogenase or by alcohol dehydrogenase i, ...19912033381
heterologous transformation of cochliobolus lunatus.a dna mediated transformation system has been developed for the filamentous fungus cochliobolus lunatus. transformants were obtained by using plasmid pan 7-1 carrying the escherichia coli hygromycin b phosphotransferase gene (hph) fused to an aspergillus nidulans promoter. the integration of plasmid pan 7-1 into the fungal genome altered the ability of this microorganism to transform progesterone.19912037226
ph regulation of penicillin production in aspergillus shown by both bioassay and high-performance liquid chromatographic (hplc) analysis, penicillin g production by aspergillus nidulans is subject to regulation by the ph of the growth medium. penicillin titres were highest at alkaline ph and in strains carrying mutations in the regulatory gene pacc which mimics the effects of growth at alkaline ph. they were lowest at acid ph and in strains carrying mutations in the pala, palb, palc, pale or palf genes which mimic the effects of growth at acid p ...19912037230
adenylate kinase isoenzymes in aspergillus nidulans.adenylate kinase isoenzymes localised in the mitochondria and in the cytosol have been detected in extracts of glucose-grown aspergillus nidulans using specific staining after electrophoresis on cellulose acetate. the isoenzymes have similar km values for amp, adp and mgatp2- but may differ in the mechanism used for internucleotide phosphate transfer.19912040420
the amdr product and a ccaat-binding factor bind to adjacent, possibly overlapping dna sequences in the promoter region of the aspergillus nidulans amds gene.the amds gene of aspergillus nidulans is regulated by a number of positively acting regulatory genes which act additively and independently. using gel mobility shift assays with crude nuclear extracts we show here that the product of one of these regulatory genes, the amdr gene, binds to dna fragments containing part of the promoter region of the amds gene. this confirms the earlier prediction from dna sequence data that amdr encodes a dna-binding protein containing a cysteine-rich 'zinc finger' ...19912041742
molecular cloning and characterization of the arod gene encoding 3-dehydroquinase from salmonella typhi.the arod gene from salmonella typhi, encoding 5-dehydroquinate hydrolyase (3-dehydroquinase), has been cloned into escherichia coli and the dna sequence determined. the arod gene was isolated from a cosmid gene bank by complementation of an s. typhimurium arod mutant. analysis of the dna sequence revealed the presence of an open reading frame capable of encoding a protein of 252 amino acids with a calculated mr of 27706. comparison of the deduced s. typhi 3-dehydroquinase protein sequence with t ...19912045778
correct intron splicing generates a new type of a putative zinc-binding domain in a transcriptional activator of aspergillus nidulans.alcr is the pathway-specific transcriptional activator of the ethanol regulon in the filamentous fungus, aspergillus nidulans. the deduced amino acid sequence of a cdna clone, including the 5' part of the alcr-mrna, shows that a putative zn-binding domain of the all-cysteine class, exemplified by gal4 is present. this structure presents some striking features. at variance with other structures of this class, the binding domain is strongly asymmetrical. model building indicates that the zinc-bind ...19912053973
in vitro studies with nine known or suspected spindle poisons: results in tests for chromosome malsegregation in aspergillus nidulans.within the framework of a coordinated collaborative study for evaluating assays for aneuploidy, nine known or suspected spindle poisons were tested in mitotic segregation assays with aspergillus nidulans. experiments with a. nidulans diploid strain p1 revealed a statistically significant increase of whole chromosome segregants (non-disjunctional diploids and haploids) after treatments with chloral hydrate (ch), thiabendazole (tb), thimerosal (tm) econazole (ez) and hydroquinone (hq). the latter ...19912056914
chromosome-specific recombinant dna libraries from the fungus aspergillus nidulans.development of physical genomic maps is facilitated by identification of overlapping recombinant dna clones containing long chromosomal dna inserts. to simplify the analysis required to determine which clones in a genomic library overlap one another, we partitioned aspergillus nidulans cosmid libraries into chromosome-specific subcollections. the eight a. nidulans chromosomes were resolved by pulsed field gel electrophoresis and hybridized to filter replicas of cosmid libraries. the subcollectio ...19912057366
delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase from aspergillus nidulans. molecular characterization of the acva gene encoding the first enzyme of the penicillin biosynthetic pathway.the aspergillus nidulans gene (acva) encoding the first catalytic steps of penicillin biosynthesis that result in the formation of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv), has been positively identified by matching a 15-amino acid segment of sequence obtained from an internal cnbr fragment of the purified amino-terminally blocked protein with that predicted from the dna sequence. acva is transcribed in the opposite orientation to ipna (encoding isopenicillin n synthetase), with an ...19912061333
nitrate reactive structural gene mutants of aspergillus nidulans.two strains characterized as niad structural gene mutants in aspergillus nidulans produce a nitrate reductase which retains the ability to react with nitrate while lacking the ability to oxidize its naturally occurring substrate nadph. fifteen such nitrate reactive niad strains exhibited strong interallelic complementation when tested against strains bearing point mutations in eleven other loci essential to induction and synthesis of nitrate reductase in aspergillus. fourteen representatives of ...19912062247
isolation and transcriptional characterization of a morphological modifier: the aspergillus nidulans stunted (stua) gene.the functions of at least four potential regulatory genes are known to overlap temporally during elaboration of the multicellular asexual reproductive apparatus (conidiophore) of aspergillus nidulans. one of these, the stua (stunted) gene, has been previously classified as a morphological modifier essential for correct spatial organization of the conidiophore. the gene was cloned by complementation of a strain carrying the stua1 mutation and has been localized to a 5.0 kb kpni fragment that enco ...19912062309
rodletless, a new aspergillus developmental mutant induced by directed gene inactivation.the aspergillus nidulans can41 transcription unit is activated by the brla regulatory gene early during development of the asexual reproductive apparatus, the conidiophore. disruption of can41 results in a novel mutant phenotype in which conidiophore cells and spores lack an external wall layer, the rodlet layer, making them less hydrophobic than in the wild type and leading to inefficient spore dispersal. the rodletless mutation defines a new locus on chromosome iii, roda. roda encodes a small, ...19912065971
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