PMID(sorted ascending)
insertion into aspergillus nidulans of functional udp-glcnac: alpha 3-d- mannoside beta-1,2-n-acetylglucosaminyl-transferase i, the enzyme catalysing the first committed step from oligomannose to hybrid and complex n-glycans.filamentous fungi are capable of secreting relatively large amounts of heterologous recombinant proteins. recombinant human glycoproteins expressed in this system, however, carry only carbohydrates of the oligomannose type limiting their potential use in humans. one approach to the problem is genetic engineering of the fungal host to permit production of complex and hybrid n-glycans. udp-glcnac:alpha 3-d-mannoside beta- 1,2-n-acetylglucosaminyltransferase i (gnt i) is essential for the conversio ...19957496151
substrate specificity of nine nad(+)-dependent alcohol dehydrogenases in aspergillus aspergillus nidulans three alcohol dehydrogenases (adhs) have been described. adhi is induced by ethanol and is the physiological enzyme of ethanol utilization, adhii has not been attributed a function but is repressed by ethanol. the alcr regulatory protein acts positively to induce adhi, and negatively in its control of adhii. adhiii is specifically induced by anaerobic stress. we have characterized the substrate specificity of these three enzymes by looking at their staining profile on pol ...19957496541
an extreme crea mutation in aspergillus nidulans has severe effects on d-glucose utilization.aspergillus nidulans wild-type and the extreme carbon catabolite derepressed mutant cread-30 were characterized with respect to enzyme activities, metabolite concentrations and polyol pools all related to glycolysis, after growth on d-glucose. in the cread-30 strain the enzymes hexokinase and fructose-6-phosphate reductase showed a two- and threefold increase in activity, respectively, whereas phosphofructokinase and pyruvate kinase activity decreased two- and threefold, respectively, in compari ...19957496542
monoclonal antibodies against a 97-kilodalton antigen from aspergillus flavus.we prepared a panel of five monoclonal antibodies (mabs) directed against aspergillus flavus that all reacted against one 97-kda antigen by western blot (immunoblot). flow cytometry demonstrated that these antibodies bound (in increasing degrees) to all morphologic stages of a. flavus growth: conidia, swollen conidia, and hyphae. cross-reactivity among species was examined by enzyme-linked immunosorbent assay of fungal culture filtrates. four mabs reacted with 10 of 11 a. flavus isolates, and th ...19947496924
signaling of ambient ph in aspergillus involves a cysteine aspergillus nidulans, the regulation of gene expression in response to changes in ambient ph is mediated by the pacc zinc finger transcriptional regulator. at alkaline ambient ph, pacc is proteolytically processed to a functional form serving as an activator of alkaline-expressed genes and a repressor of acid-expressed genes. this activation of pacc occurs in response to a signal mediated by the products of the pal genes. thus, the products of the pala, -b, -c, -f, -h, and -i genes constitute ...19957499363
structural analysis of pks1, a polyketide synthase gene involved in melanin biosynthesis in colletotrichum lagenarium.albino mutants (pks-) of colletotrichum lagenarium form nonmelanized appressoria and possess little penetrating ability on the host plant. the defect in albino mutant 79215 (pks-) is considered to lie in pentaketide biosynthesis and/or pentaketide cyclization during melanin biosynthesis. the cosmid pac7, carrying the pks1 gene, when transformed into the albino mutant restores the wild-type melanin phenotype. we have determine the dna sequence and the transcriptional organization of the pks1 gene ...19957500937
two group i introns with a c.g basepair at the 5' splice-site instead of the very highly conserved u.g basepair: is selection post-translational?in virtually all of the 200 group i introns sequenced thus far, the specificity of 5' splice-site cleavage is determined by a basepair between a uracil base at the end of the 5' exon and a guanine in an intron guide sequence which pairs with the nucleotides flanking the splice-site. it has been reported that two introns in the cytochrome oxidase subunit i gene of aspergillus nidulans and podospora anserina are exceptions to this rule and have a c.g basepair in this position. we have confirmed th ...19957501471
mitotic catastrophe is the mechanism of lethality for mutations that confer mutagen sensitivity in aspergillus nidulans.we have examined the consequences of treatment with dna-damaging agents of uvs mutants and the bimd6 mutant of aspergillus nidulans. we first established that wild-type aspergillus undergoes a cell cycle delay following treatment with the dna-damaging agents methyl methanesulfonate (mms) or ultraviolet light (uv). we have also determined that strains carrying the bimd6, uvsb110, uvsh77, uvsf201 and the uvsc114 mutations, all of which cause an increased sensitivity to dna-damaging agents, undergo ...19947506362
metabolism of folate glutamates in aspergillus nidulans. 19937508173
genotoxic activity of mebendazole in aspergillus nidulans.mebendazole is an anthelmintic drug widely used in cuba and in mexico. its interaction with tubulin interferes with the assemblage of the mitotic apparatus in the parasite cells, thus suggesting a possible genotoxic activity leading to chromosomal malsegregation. the heterozygous diploid strain d30 of aspergillus nidulans was used to establish the ability of mebendazole to induce mitotic recombination and/or chromosomal non-disjunction, and the haploid strain fgsc #219 of a. nidulans was used to ...19947510023
the genetic activity of 6-n-hydroxylaminopurine in aspergillus nidulans.the activity of a base analog (6-n-hydroxylaminopurine, hap) has been tested on aspergillus nidulans. in germinating haploid conidia hap is a strong mutagen, while it does not have any activity in resting conidia. moreover, hap does not increase the frequency of recombination in germinating conidia. the mutagenic activity of this base analog has also been tested in diploid conidia of a. nidulans; in fact, it has been shown (pavlov et al., 1991) that the hap-induced frequency of heteroallelic rec ...19947510841
a test for uniparental disomy in saccharomyces cerevisiae.uniparental disomy is a condition in a diploid organisms where one parental chromosome is absent and its homolog from the other parent duplicated. it can be a cause of genetic somatic disease in mammals because of imprinting. imprinting creates a sex-specific pattern of epigenetic gene inactivation at least in mammals and, consequently, a complete set of both maternal and paternal chromosomes is required for normal development. moreover, it has been shown for several types of tumors that recessi ...19947512218
mycoflora of post-harvest maize and wheat grains and the implication of their contamination by molds.thirteen fungi including toxigenic aspergillus nidulans and a. clavatus were isolated from the grains. the isolated fungi grew well at 25-30 degrees c. a. clavatus and a. nidulans were grown in liquid maize yeast extract medium and wheat yeast extract medium. both fungi produced amylases on the two media and on the basal medium at 30 degrees c. during incubation more total reducing sugars were detected in maize grains than in wheat while non-reducing sugars were detected than reducing sugars in ...19947518052
cell cycle-dependent expression of nek2, a novel human protein kinase related to the nima mitotic regulator of aspergillus nidulans.the serine/threonine protein kinase nima of aspergillus nidulans is required for entry into mitosis and may function in parallel to the universal mitotic inducer p34cdc2. here, we report the isolation of complementary dnas encoding nek2 and nek3, two novel human protein kinases structurally related to nima. sequence comparisons revealed several unique features which may define a family of nima-related protein kinases. nek2 was chosen for further study since it represents the closest known mammal ...19947522034
molecular and cellular parameters controlling the immunogenicity of foreign b- or t-cell epitopes expressed by recombinant vectors.extensive work is being performed to develop live recombinant bacterial vaccines. the use of non-pathogenic bacteria or attenuated strains derived from pathogens may allow protection against the pathogen and at the same time induce immunity against one or several foreign antigens expressed by the recombinant micro-organism. several bacteria such as attenuated salmonella or bcg have been used successfully in several experimental models to induce protective immune responses against several pathoge ...19947525391
nitrite reductase gene cloning of amycolatopsis mediterranei u-32.southern blot analysis showed great homology existed between niad (nr gene) of aspergillus nidulans and a. mediterranei u-32 chromosome dna. a 5.0kb psti fragment from a. mediterranei u-32 complementary to a. nidulans niad gene was cloned in e. coli nm522 using niad as a probe. an identical dna band was observed through back-hybridization of the cloned dna fragment to psti digest of a. mediterranei u-32 chromosome dna. its 2.1 kb smai-ecorv fragment can only hybridize with total rna from nitrate ...19947534488
based on biochemical and physiological behavior, where is aspergillus egyptiacus better placed?physiological and biochemical properties were tested in 45 isolates of aspergillus egyptiacus (16 isolates), emericella nidulans (16) and aspergillus versicolor (13). the three fungal species exhibited common and similar features. the big similarity between a. egyptiacus and e. nidulans was greater than between a. egyptiacus and a. versicolor. it included the inability to produce base either from sodium citrate or lactic acid media, growth at 45 degrees c (thermophilicity), and production of ver ...19947537240
salt sensitivity and arginine toxicity in aspergillus nidulans. 19957538946
copper-induced changes in the urea uptake and urease activity in the cyanobacteria anabaena doliolum and anacystis nidulans: interaction with sulphur containing amino acids.copper-induced changes in the urea uptake and urease activity have been investigated in the cyanobacteria anabaena doliolum and anacystis nidulans. copper, at and above 5 mumol/l concentration, inhibited urea uptake and urease activity systems in both the cyanobacteria in a concentration dependent manner. however, the urea uptake and urease activity systems in a. nidulans appeared slightly more tolerant to copper than than of a. doliolum. the inhibitory effect of copper on urea uptake and urease ...19957546344
analysis of a mycotoxin gene cluster in aspergillus nidulans.aspergillus nidulans has functioned as a model system for the study of fungal genetics since the 1950s. application of methodologies ranging from mendelian genetics to the most sophisticated molecular biological techniques have resulted in a detailed understanding of genes and pathways involved in primary metabolism, secondary metabolism and development in a. nidulans. we have taken advantage of this background in developing a. nidulans as a genetic system to study the molecular mechanisms regul ...19957546572
cloning and nucleotide sequence of the calmodulin-encoding gene (cmda) from aspergillus oryzae.a cdna and genomic gene encoding calmodulin were isolated from aspergillus oryzae using a part of the calmodulin gene from a. nidulans as a hybridization probe. the gene was in a 3.4-kb sphi fragment and southern-blot analysis of genomic dna suggested the existence of a single copy of the calmodulin gene in a. oryzae. the nucleotide sequence analysis showed that the gene consists of five introns and six exons. although the nucleotide sequence homology with that of a. nidulans was not so high (68 ...19957549095
a pre-induction sporulation gene from aspergillus nidulans.asexual sporulation in aspergillus nidulans is an inducible developmental process controlled by genes that act before and after the inductive stimulus is applied. genes that act before induction (pre-induction genes) potentially represent functions required for response to induction. this report describes the isolation and characterization of the acob pre-induction gene which was cloned by complementation of a thermosensitive aconidial mutant followed by gene rescue. genetic analysis and gene di ...19957551046
the aspergillus parasiticus polyketide synthase gene pksa, a homolog of aspergillus nidulans wa, is required for aflatoxin b1 biosynthesis.aflatoxins comprise a group of polyketide-derived carcinogenic mycotoxins produced by aspergillus parasiticus and aspergillus flavus. by transformation with a disruption construct, pxx, we disrupted the aflatoxin pathway in a. parasiticus srrc 2043, resulting in the inability of this strain to produce aflatoxin intermediates as well as a major yellow pigment in the transformants. the disruption was attributed to a single-crossover, homologous integration event between pxx and the recipient a. pa ...19957565588
the intergenic region between the divergently transcribed niia and niad genes of aspergillus nidulans contains multiple nira binding sites which act bidirectionally.the niad and niia genes of aspergillus nidulans, which code, respectively, for nitrate and nitrite reductases, are divergently transcribed, and their atgs are separated by 1,200 bp. the genes are under the control of the positively acting nira transcription factor, which mediates nitrate induction. the dna binding domain of nira was expressed as a fusion protein with the glutathione s-transferase of schistosoma japonicum. gel shift and footprint experiments have shown that in the intergenic regi ...19957565720
fungal metabolic model for human type i hereditary tyrosinaemia.type i hereditary tyrosinaemia (ht1) is a severe human inborn disease resulting from loss of fumaryl-acetoacetate hydrolase (fah). homozygous disruption of the gene encoding fah in mice causes neonatal lethality, seriously limiting use of this animal as a model. we report here that faha, the gene encoding fah in the fungus aspergillus nidulans, encodes a polypeptide showing 47.1% identity to its human homologue, faha disruption results in secretion of succinylacetone (a diagnostic compound for h ...19957568087
characterization and localization of the cytoplasmic dynein heavy chain in aspergillus nidulans.migration of nuclei throughout the mycelium is essential for the growth and differentiation of filamentous fungi. in aspergillus nidulans, the nuda gene, which is involved in nuclear migration, encodes a cytoplasmic dynein heavy chain. in this paper we use antibodies to characterize the aspergillus cytoplasmic dynein heavy chain (acdhc) and to show that the acdhc is concentrated at the growing tip of the fungal mycelium. we demonstrate that four temperature-sensitive mutations in the nuda gene r ...19957568239
does gene palb regulate the transcription or the post-translational modification of pi-repressible phosphatases of aspergillus nidulans?when grown on low-pi medium, the chaa1 pabaa1 palb7 mutant of aspergillus nidulans excretes an acid phosphatase with steady-state kinetic properties, temperature sensitivity and electrophoretic mobility different from those of the enzyme excreted by the pabaa1 strain. the enzyme excreted by the pabaa1 strain at ph 6.5 showed pnp-p activity with negative cooperativity (k0.5 = 0.87 +/- 0.06 mm, n = 0.68 +/- 0.03) whereas the enzyme excreted by the chaa1 pabaa1 palb7 mutant showed michaelian kineti ...19957581026
aspergillus fumigatus antigens.cytosolic fractions of mycelial extracts from aspergillus nidulans, a. flavus, and three different isolates of a. fumigatus, grown to stationary phase in czapek-dox-aoac medium, were tested by immunoblotting for the presence of antigens reactive to 80 serum samples from aspergilloma patients. fifty control serum samples were used to determine the specificity of the reactions. in the a. fumigatus cytosolic fraction a group of four main antigenic bands (p90, p60, p40 and p37) was consistently reco ...19957582030
design of an object-oriented database for reverse genetics.we present the design of an object-oriented database system for reverse genetics applications. such a database will encapsulate not only the data in the genetic and physical maps, but also the methods used to create the maps as well as methods to link them to other databases, such as genbank, pir, and medline. the purpose of this database is to provide the fungal genetics community with an electronic tool for identifying the biochemical function of any dna fragment in the database--electronic re ...19937584341
molecular biological analysis of a bidirectional hydrogenase from 8.9-kb segment with hydrogenase genes from the cyanobacterium anabaena variabilis has been cloned and sequenced. the sequences show homology to the methyl-viologen-reducing hydrogenases from archaebacteria and, even more striking, to the nad(+)-reducing enzymes from alcaligenes eutrophus and nocardia opaca as well as to the nadp(+)-dependent protein from desulfovibrio fructosovorans. the cluster from a. variabilis contains genes coding for both the hydrogenase heterodimer (hoxh and hoxy) and ...19957588754
post-transcriptional control and kinetic characterization of proline transport in germinating conidiospores of aspergillus the filamentous fungus aspergillus nidulans, l-proline uptake is mediated by the product of the prnb gene which codes for a member of a family of amino acid transporters found both in pro- and eukaryotes. regulation of prnb gene expression has previously been studied in great detail at the molecular level. however, no studies have addressed possible post-transcriptional controls or the kinetic characterisation of the prnb transporter. here we develop a rapid and efficient method for direct up ...19957590163
a lacz reporter fusion method for the genetic analysis of regulatory mutations in pathways of fungal secondary metabolism and its application to the aspergillus nidulans penicillin pathway.secondary metabolism, usually superfluous under laboratory conditions, is intrinsically elusive to genetic analysis of its regulation. we describe here a method of analyzing regulatory mutations affecting expression of secondary metabolic genes, with an aspergillus nidulans penicillin structural gene (ipna [encoding isopenicillin n-synthase]) as a model. the method is based on a targeted double integration of a lacz fusion reporter gene in a chromosome different from that containing the penicill ...19957592369
phanerochaete chrysosporium glyoxal oxidase is encoded by two allelic variants: structure, genomic organization, and heterologous expression of glx1 and glx2.a cdna clone (glx-2c) encoding glyoxal oxidase (glox) was isolated from a phanerochaete chrysosporium lambda gt11 library, and its nucleotide sequence was shown to be distinct from that of the previously described clone glx-1c (p. j. kersten and d. cullen, proc. natl. acad. sci. usa 90:7411-7413, 1993). genomic clones corresponding to both cdnas were also isolated and sequenced. overall nucleotide sequence identity was 98%, and the predicted proteins differed by a single residue: lys-308<==>thr- ...19957592374
a novel nitrite reductase gene from the cyanobacterium plectonema boryanum.the gene (nira) for nitrite reductase was cloned from the nonheterocystous, filamentous cyanobacterium plectonema boryanum. the predicted protein consists of 654 amino acids and has a calculated molecular weight of 72,135. the deduced amino acid sequence from positions 1 to 511 is strongly similar to the entire sequence of the ferredoxin-dependent nitrite reductases from other phototrophs, while the remainder of the protein is unique to the plectonema nitrite reductase. the c-terminal portion of ...19957592378
nucleotide sequence and characterization of the large mitochondrial rrna gene of penicillium urticae, and its comparison with those of other filamentous fungi.the nucleotide sequence of a large rrna gene and its flanking regions in cloned fragments of mitochondrial dna from a patulin producer, penicillium urticae nrrl2159a, was determined by dideoxy sequencing, and the 5' end and intron-exon border of the 1-rrna gene were determined by primer extension analysis and rna sequencing, respectively. in addition to the extensive sequence homology of the 3' end of the p. urticae mt 1-rrna gene with those of aspergillus nidulans and neurospora crassa, the p. ...19957592555
the positively acting amda gene of aspergillus nidulans encodes a protein with two c2h2 zinc-finger motifs.semi-dominant mutations in the amda gene lead to elevated expression of the gene encoding acetamidase, amds. these mutations also cause constitutive expression of the acetate-inducible gene, acia. in the amds 5' regulatory region, two cis-acting mutations, amdl66 and amdl666, have been isolated which specifically affect amda activation of amds. these mutations are a duplication and a triplication of an 18 bp ga-rich sequence, thought to define the amda site of action within the amds promoter reg ...19957596297
a single amino acid change in a pathway-specific transcription factor results in differing degrees of constitutivity, hyperinducibility and derepression of several structural genes.unyc462 is a gain-of-function mutation in the purine catabolism positive regulatory gene of aspergillus nidulans. this allele leads to a constitutive, hyperinducible and derepressed expression of a least three genes controlled by uay, and this occurs at different levels depending on the target gene. the uayc462 allele was mapped physically in relation to known loss-of-function alleles and sequenced. uayc462 is a one-base change in codon 222, resulting in a serine to leucine change. we propose th ...19957602582
nudf, a nuclear migration gene in aspergillus nidulans, is similar to the human lis-1 gene required for neuronal migration.during a study of the genetics of nuclear migration in the filamentous fungus aspergillus nidulans, we cloned a gene, nudf, which is required for nuclear migration during vegetative growth as well as development. the nudf protein level is controlled by another protein nudc, and extra copies of the nudf gene can suppress the nudc3 mutation. nudf encodes a protein with 42% sequence identity to the human lis-1 (miller-dieker lissencephaly-1) gene, which is required for proper neuronal migration dur ...19957612965
aspergillus nidulans mutants affected in acetate metabolism isolated as lipid nonutilizers.interest in extracellular fungal lipases has increased mainly because of their industrial applications. however, no studies have been done on a genetically well characterized filamentous fungus like aspergillus nidulans. here we show that a. nidulans produces an extracellular lipase when grown in solid or liquid cultures containing lipids as carbon source. this lipase is glucose-repressed in a crea-independent fashion. seven mutants isolated by their inability to utilize lipids as sole carbon so ...19957614370
niaa, the structural nitrate reductase gene of phytophthora infestans: isolation, characterization and expression analysis in aspergillus nidulans.the nitrate reductase (nr) gene niaa of the oomycete phytophthora infestans was selected from a gene library by heterologous hybridization. niaa occurs as a single-copy gene ant its expression is regulated by the nitrogen source. the nucleotide sequence of niaa was determined and comparison of the deduced amino-acid sequence of 902 residues with nrs of higher fungi and plants revealed a significant homology, particularly within the three cofactor-binding domains for molybdenum, heme and fad. the ...19957614559
malvolio, the drosophila homologue of mouse nramp-1 (bcg), is expressed in macrophages and in the nervous system and is required for normal taste behaviour.we report the sequence, expression pattern and mutant phenotype of malvolio (mvl), the drosophila homologue of mammalian natural resistance-associated macrophage proteins (nramps). in the mouse, this novel transporter is encoded by bcg, a dominant gene that confers natural resistance to intracellular parasites. mvl was identified in a screen for mutants that affect taste behaviour. we show that loss-of-function as well as insertional mutants in mvl display defects in taste behaviour with no alte ...19957621816
activation of the aspergillus pacc transcription factor in response to alkaline ambient ph requires proteolysis of the carboxy-terminal moiety.extremes of ph are an occupational hazard for many microorganisms. in addition to efficient ph homeostasis, survival effectively requires a regulatory system tailoring the syntheses of molecules functioning beyond the cell boundaries (permeases, secreted enzymes, and exported metabolites) to the ph of the growth environment. our previous work established that the zinc finger pacc transcription factor mediates such ph regulation in the fungus aspergillus nidulans in response to a signal provided ...19957628696
sequence and structure of penicillium chrysogenum phog, homologous to an acid phosphatase-encoding gene of aspergillus nidulans.a penicillium chrysogenum (pc) gene (phog), homologous to an aspergillus nidulans (an) gene which confers phosphate-non-repressible acid phosphatase (apase) activity, has been cloned and sequenced. the 2.9-kb genomic sequence corresponds to two orfs of 149 and 1630 bp encoding a protein of 593 amino acids (aa). as verified by cdna sequencing, the coding region is interrupted by an 85-bp intron. the deduced aa sequence of phog reveals 61% aa identity to the translated long orf of the an apase-enc ...19957628710
isolation of a functional homolog of the cell cycle-specific nima protein kinase of aspergillus nidulans and functional analysis of conserved investigate the degree of conservation of the cell cycle-specific nima protein kinase of aspergillus nidulans, and to help direct its functional analysis, we cloned a homolog (designated nim-1) from neurospora crassa. over the catalytic domain nim-1 is 75% identical to nima, but overall the identity drops to 52%. nim-1 was able to functionally complement nima5 in a. nidulans. mutational analysis of potential activating phosphorylation sites found in nima, nim-1, and related protein kinases wa ...19957629122
the basal level of transcription of the alc genes in the ethanol regulon in aspergillus nidulans is controlled both by the specific transactivator alcr and the general carbon catabolite repressor the a. nidulans ethanol utilization pathway, specific induction is mediated by the transactivator alcr which is subject to strong positive autogenous regulation and activates the transcription of the two structural genes alca and alda. carbon catabolite repression is mediated by crea which represses directly the transacting gene alcr and the two structural genes. we show here that the basal expression of the alcr and alca genes is also controlled by the two regulatory circuits, positively by ...19957635218
effects of leader sequences upon the heterologous expression of restrictocin in aspergillus nidulans and aspergillus niger.the effects of altered leader sequences on the secretion and localization of restrictiocin expression in aspergillus nidulans and aspergillus niger were investigated. the region encoding the leader sequence of the aspergillus restrictus restrictocin (res) gene was altered and variants were expressed under the glucoamylase (glaa) promoter in a. nidulans and a. niger. the entire restrictocin leader sequence was replaced by the glaa leader sequence in one variant. in another, the signal sequence of ...19957641142
structure, organization and promoter expression of the actin-encoding gene in trichoderma reesei.the single gene encoding actin (act) in the cellulolytic filamentous fungus trichoderma reesei (tr) has been isolated and characterized. the gene contains five introns located in identical positions when compared to the putative ancestral actin genes (act) present in thermomyces lanuginosus and aspergillus nidulans. the 5' untranslated region (utr) of the gene contains a tata-like sequence (taata), a c + t-rich region and a potential ccaat motif. this region was used as a homologous promoter to ...19957642121
carbon source-dependent regulation of the acetyl-coenzyme a synthetase-encoding gene acs1 from saccharomyces cerevisiae.the yeast acs1 gene, encoding acetyl-coenzyme a synthetase (acs), was cloned using colony hybridization and a faca probe from aspergillus nidulans. the complete sequence of 1.5 kb of the acs1 upstream region was determined. northern hybridization revealed a strong depression of acs1 transcripts in a strain grown on the nonfermentable carbon sources, acetate or ethanol. in contrast to a previous report, delta acs1 null mutants did not exhibit a growth defect on acetate medium. indeed, enzyme assa ...19957642141
sterigmatocystin biosynthesis in aspergillus nidulans requires a novel type i polyketide synthase.a filamentous fungus, aspergillus nidulans, produces the carcinogenic mycotoxin sterigmatocystin (st), which is a polyketide-derived secondary metabolite. a gene (pksst) encoding the st polyketide synthase (pksst) in a. nidulans was cloned, sequenced, and characterized. large induced deletion mutants, which did not make st or any st intermediates, were used to identify genes associated with st biosynthesis. among the transcripts detected within the deletion region, which showed developmental exp ...19957642507
dewa encodes a fungal hydrophobin component of the aspergillus spore anonymous cdna clone, pcan4, was shown previously to correspond to an mrna that accumulates preferentially during asexual sporulation of the filamentous fungus aspergillus nidulans. the peptide encoded by pcan4 is a fungal hydrophobin, a group of small, hydrophobic cell wall proteins. when the can4 gene was disrupted, conidia and conidiophores appeared to be normal, but sporulating colonies wetted more rapidly with detergent solutions than did the wild type. we renamed can4 dewa for the deter ...19957651135
the aspergillus uvsh gene encodes a product homologous to yeast rad18 and neurospora uvs-2.the uvsh dna repair gene of aspergillus nidulans has been cloned by complementation of the uvsh77 mutation with a cosmid library containing genomic dna inserts from a wild-type strain. methylmethane sulfonate (mms)-resistant transformants were obtained on medium containing 0.01% mms, to which uvsh mutants exhibit high sensitivity. retransformation of uvsh77 mutants with the rescued cosmids from the mms-resistant transformants resulted in restoration of both uv and mms resistance to wild-type lev ...19957651340
the fusarium solani gene encoding kievitone hydratase, a secreted enzyme that catalyzes detoxification of a bean phytoalexin.among the antimicrobial phytoalexins produced by phaseolus vulgaris (french bean) is the prenylated isoflavonoid, kievitone. the bean pathogen, fusarium solani f. sp. phaseoli, secretes a glycoenzyme, kievitone hydratase (ec, which catalyzes conversion of kievitone to a less toxic metabolite. among f. solani strains, those that are highly virulent to p. vulgaris also produce kievitone hydratase constitutively, suggesting that the enzyme is a virulence factor. based on the n-terminal am ...19957655061
quantitation of oligohistidine fusion proteins using 63ni2+ chelation. 19957659532
genetic nomenclature guide. aspergillus nidulans. 19957660460
crystallization and preliminary x-ray diffraction studies on recombinant isopenicillin n synthase from aspergillus nidulans.recombinant aspergillus nidulans isopenicillin n synthase was purified from an escherichia coli expression system. the apoenzyme in the presence of saturating concentrations of mncl2 could be crystallized by either macro- or microseeding, using the hanging drop vapor diffusion technique with polyethylene glycol 8000 as precipitant. the crystals (0.5-1.0 mm overall dimensions) diffract x-rays to at least 2.0 a resolution at synchrotrons and belong to space group p212121 with unit cell dimensions ...19957663335
molecular cloning and heterologous expression of the gene encoding dihydrogeodin oxidase, a multicopper blue enzyme from aspergillus terreus.aspergillus terreus dihydrogeodin oxidase (dhgo) is an enzyme catalyzing the stereospecific phenol oxidative coupling reaction converting dihydrogeodin to (+)- geodin. we previously reported the purification of dhgo from a. terreus and raised polyclonal antibody against dhgo. from the first cdna library constructed in lambda gt11 using mrna from 3-day-old mycelium of a. terreus, four clones were identified using anti-dhgo antibody, but all contained partial cdna inserts around 280 base pairs. th ...19957665560
phylogenetic relationships of five species of aspergillus and related taxa as deduced by comparison of sequences of small subunit ribosomal rna.the nucleotide sequences of the genes encoding the 18s rrna of aspergillus flavus, a. nidulans, a. terreus and a. niger were elucidated and aligned to the sequences of a. fumigatus. in addition, the 18s rrna sequences of the v4-v9 region of morphologically similar filamentous fungi, e.g. penicillium chrysogenum, p. marneffei and paecilomyces variotii, were elucidated. phylogenetic analysis and comparison showed a very close intergeneric relationship of the genus aspergillus to species of the gen ...19957666299
the mig1 repressor from kluyveromyces lactis: cloning, sequencing and functional analysis in saccharomyces cerevisiae.sequence comparisons between saccharomyces cerevisiae scmig1 and aspergillus nidulans crea proteins allowed us to design two sets of degenerate primers from the conserved zinc finger loops. pcr amplification on kluyveromyces marxianus and k. lactis genomic dna yielded single products with sequences closely related to each other and to the corresponding regions of scmig1 and crea. the kimig1 gene of k. lactis was cloned from a genomic library using the k. marxianus pcr fragment as probe. kimig1 e ...19957672126
molecular characterization of a gene encoding a homogentisate dioxygenase from aspergillus nidulans and identification of its human and plant homologues.we report here the first characterization of a gene encoding a homogentisate dioxygenase, the aspergillus nidulans hmga gene. the hmga protein catalyzes an essential step in phenylalanine catabolism, and disruption of the gene results in accumulation of homogentisate in broths containing phenylalanine. hmga putatively encodes a 448-residue polypeptide (mr = 50,168) containing 21 histidine and 23 tyrosine residues. this polypeptide has been expressed in escherichia coli as a fusion to glutathione ...19957673153
use of reporter genes to identify recessive trans-acting mutations specifically involved in the regulation of aspergillus nidulans penicillin biosynthesis genes.starting from three amino acid precursors, penicillin biosynthesis is catalyzed by three enzymes which are encoded by the following three genes: acva (pcbab), ipna (pcbc), and aat (pende). to identify trans-acting mutations which are specifically involved in the regulation of these secondary metabolism genes, a molecular approach was employed by using an aspergillus nidulans strain (axtii9) carrying acva-uida and ipna-lacz gene fusions integrated in double copies at the chromosomal argb gene. on ...19957677843
nucleotide sequence of the large mitochondrial rrna gene of penicillium chrysogenum.the nucleotide sequence of a large rrna (1-rrna) gene and its flanking regions in the cloned fragments of mitochondrial (mt) dna from penicillium chrysogenum nrrl1951 (sekiguchi j., ohsaki, t., yamamoto, h., koichi, k. and shida, t. (1990) j. gen. microbiol. 136, 535-543) was determined and compared with those in aspergillus nidulans and neurospora crassa mitochondrial dnas. the p. chrysogenum mt 1-rrna gene has a 1678 bp intron which intervenes between a 2835 bp 5' exon and a 581 bp 3' exon, an ...19937680578
an evaluation of the use of in vitro tubulin polymerisation, fungal and wheat assays to detect the activity of potential chemical aneugens.the test chemicals included in the ec aneuploidy project were evaluated for their ability to induce aneuploidy or aneuploidy related endpoints in assays using in vitro tubulin polymerisation, fungi and wheat. the results obtained demonstrated considerable qualitative and quantitative differences between the responses of the assays to the 10 test chemicals. fungal assays failed to respond to the potent mammalian spindle poisons colchicine and vinblastine and only three chemicals were positive in ...19937683381
production and characterization of sterigmatocystin.fourteen strains of aspergillus versicolor and 2 strains of a. nidulans were screened for sterigmatocystin (st) production on a semi-synthetic solid substrate by high performance liquid chromatography (hplc) analysis. two strains of a. versicolor producing st at 550.5 substrate and 1160.8 substrate were selected to inoculate 4 kg solid st-producing media. after 30 days stationary incubation at 28 degrees c in the dark, 2271.6 mg of pale-yellow needle-shaped crystals were isolated ...19947702759
sequence around the 159 degree region of the bacillus subtilis genome: the pksx locus spans 33.6 kb.the nucleotide sequence of 20 kb contiguous to the pksx locus of bacillus subtilis was determined. six orfs were recognized, one of which extended for 13,341 nucleotides. their predicted products have significant similarities to proteins with known functions involved in the synthesis of polypeptides and polyketides or in fatty acid metabolism. at the nucleotide level, three regions with a high level of sequence identity (49-54%) to the aspergillus nidulans wa gene, responsible for the synthesis ...19957704258
cdna structure and characterization of a kinesin-like protein from the silkworm bombyx mori.we have isolated a 1224 bp cdna clone from a bombyx mori embryonic cdna library which contains sequences homologous to the kinesin-like protein gene, ncd, which is required for distribution of chromosomes at meiosis in drosophila melanogaster females. this clone includes both a microtubule motor and the atp-binding domains found in kinesin-like proteins. the motor domain is classified in the group of the bimc and cut7, which have a role in spindle formation during mitosis of aspergillus nidulans ...19947704303
cellular effects of misscheduled brla, abaa, and weta expression in aspergillus nidulans.asexual sporulation in the fungus aspergillus nidulans is controlled, in part, by a central regulatory pathway composed of the brla, abaa, and weta genes. the coding region of each of these genes was fused, in frame, to the threonine-inducible alcohol dehydrogenase promotor then stably incorporated into the a. nidulans genome at the argb locus. misscheduled expression of each of these developmental genes interfered with normal growth and sporulation. expression of brla or abaa terminated vegetat ...19947704830
identification of developmental regulatory genes in aspergillus nidulans by overexpression.overexpression of several aspergillus nidulans developmental regulatory genes has been shown to cause growth inhibition and development at inappropriate times. we set out to identify previously unknown developmental regulators by constructing a nutritionally inducible a. nidulans expression library containing small, random genomic dna fragments inserted next to the alca promoter [alca(p)] in an a. nidulans transformation vector. among 20,000 transformants containing random alca(p) genomic dna fu ...19957713416
genetic and molecular characterization of a gene encoding a wide specificity purine permease of aspergillus nidulans reveals a novel family of transporters conserved in prokaryotes and aspergillus nidulans, loss-of-function mutations in the uapa and azga genes, encoding the major uric acid-xanthine and hypoxanthine-adenine-guanine permeases, respectively, result in impaired utilization of these purines as sole nitrogen sources. the residual growth of the mutant strains is due to the activity of a broad specificity purine permease. we have identified uapc, the gene coding for this third permease through the isolation of both gain-of-function and loss-of-function mutations. u ...19957721763
molecular biological and biochemical aspects of fungal dimorphism. 19947722802
the sequence and binding specificity of uay, the specific regulator of the purine utilization pathway in aspergillus nidulans, suggest an evolutionary relationship with the ppr1 protein of saccharomyces cerevisiae.the uay gene codes for a transcriptional activator mediating the induction of a number of unlinked genes involved in purine utilization in aspergillus nidulans. here we present the complete genomic and cdna nucleotide sequence of this gene. the gene contains two introns. the derived polypeptide of 1060 residues contains a typical zinc binuclear cluster domain and shows a number of similarities with the ppr1 regulatory gene of saccharomyces cerevisiae. these similarities are most striking in the ...19957729421
how many 5s rrna genes and pseudogenes are there in aspergillus nidulans?we have estimated the number of 5s rrna genes in aspergillus nidulans using two-dimensional agarose gel electrophoresis and hybridization to appropriate probes, representing the 5'-halves, the 3'-halves of the 5s rrna sequence and a sequence found at the 3'-end of all known a. nidulans pseudogenes (block c). we have found 23 5s rrna genes, 15 pseudogenes consisting of the 5'-half of the 5s rrna sequence (of which 3 are flanked by block c) and 12 copies of block c which do not seem to be in the v ...19947732763
purification of arginase from aspergillus nidulans.arginase (ec of aspergillus nidulans, the enzyme which enables the fungus to use arginine as the sole nitrogen source was purified to homogeneity. molecular mass of the purified arginase subunit is 40 kda and is similar to that reported for the neurospora crassa (38.3 kda) and saccharomyces cerevisiae (39 kda) enzymes. the native molecular mass of arginase is 125 kda. the subunit/native molecular mass ratio suggests a trimeric form of the protein. the arginase protein was cleaved and pa ...19947732765
evidence for a nima-like mitotic pathway in vertebrate cells.nima is essential for entry into mitosis in aspergillus nidulans. to examine whether there is a nima-like pathway in other eukaryotic cell cycles, we expressed nima and its dominant negative mutants in two different eukaryotic systems. in xenopus oocytes, nima induced germinal vesicle breakdown without activating mos, cdc2, or map kinase. in hela cells, nima induced premature mitotic events without activating cdc2, whereas the mutants caused a specific g2 arrest but did not block mutant cdc2t14a ...19957736593
development of primer sets designed for use with the pcr to amplify conserved genes from filamentous ascomycetes.we constructed nine sets of oligonucleotide primers on the basis of the results of dna hybridization of cloned genes from neurospora crassa and aspergillus nidulans to the genomes of select filamentous ascomycetes and deuteromycetes (with filamentous ascomycete affiliations). nine sets of primers were designed to amplify segments of dna that span one or more introns in conserved genes. pcr dna amplification with the nine primer sets with genomic dna from ascomycetes, deuteromycetes, basidiomycet ...19957747954
genetic requirements for initiating asexual development in aspergillus nidulans.conidiation in the filamentous ascomycete aspergillus nidulans requires activation of brla, a well-characterized transcriptional regulator of genes that are induced specifically during asexual development. we have isolated and characterized developmental mutations in six loci, designated flug, flba, flbb, flbc, flbd, and flbe, that result in defective development and reduced brla expression. these mutants grow indeterminately to produce masses of aerial hyphae resulting in the formation of cotto ...19947750148
purification and characterization of assembly-competent tubulin from aspergillus nidulans.we have developed a procedure for purifying assembly-competent tubulin from aspergillus nidulans. to our knowledge, this is the first report of the purification of assembly-competent tubulin from a filamentous fungus, and the procedure should be of great value in analyzing the large number of alpha- and beta-tubulin mutations that have been isolated and characterized in a. nidulans. our procedure consists of overproduction of alpha- and beta-tubulin, partial purification by ion-exchange chromato ...19957756266
substrate specificity and cell cycle regulation of the nek2 protein kinase, a potential human homolog of the mitotic regulator nima of aspergillus nidulans.the human nek2 protein kinase is the closest known mammalian relative of the mitotic regulator nima of aspergillus nidulans. the two kinases share 47% sequence identity over their catalytic domains and display a similar cell cycle-dependent expression peaking at the g2 to m phase transition. hence, it is attractive to speculate that human nek2 and fungal nima may carry out similar functions at the onset of mitosis. to study the biochemical properties and substrate specificity of human nek2 and c ...19957759549
a glucose-derepressed promoter for expression of heterologous products in the filamentous fungus aspergillus nidulans.we describe a putative binding sequence (gcggggc) for the glucose-responsive repressor protein crea at two positions upstream of the transcription start site of the alcohol dehydrogenase i (alca) gene of aspergillus nidulans. to positively identify the putative binding sites as crea-specific, the gcggggc blocks were mutated at five internal nucleotide positions to gtactac and reintroduced into the wild type alca promoter driving expression of the endogenous alcohol dehydrogenase i gene. this cre ...19937763860
cloning of the aspergillus niger gene encoding alpha-l-arabinofuranosidase a.using l-arabitol as an inducer, simple induction conditions were established that resulted in high-level expression of alpha-l-arabinofuranosidase a by an aspergillus niger d-xylulose kinase mutant strain. these conditions were adapted to construct a cdna expression library from which an alpha-l-arabinofuranosidase a cdna clone was isolated using specific antiserum. the corresponding gene encoding alpha-l-arabinofuranosidase a (abfa) was isolated from a genomic library and cloned into a high cop ...19937764056
molecular cloning and sequence analysis of the cellobiohydrolase i gene from trichoderma koningii g-39.the cellobiohydrolase i gene, cbh1, has been cloned from an enhanced cellulase-producing strain, trichoderma koningii g-39. sequence comparisons show that t. koningii cbh1 is identical to that of t. reesei with the exception of 6 bp--two causing silent substitutions in the coding region, three differing in one of the introns, and one in 5'-noncoding region. thus, it should encode an identical cbhi to that of t. reesei despite the differences in morphological characters of the two species. analys ...19947764306
molecular cloning, expression and structure of the endo-1,5-alpha-l-arabinase gene of aspergillus niger.secretion of endo-1,5-alpha-l-arabinase a (abn a) by an aspergillus niger xylulose kinase mutant upon mycelium transfer to medium containing l-arabitol was immunochemically followed with time to monitor its induction profile. a cdna expression library was made from polya+ rna isolated from the induced mycelium. this library was immunochemically screened and one abn a specific clone emerged. the corresponding abna gene was isolated from an a. niger genomic library. upon southern blot analysis, a ...19937764386
expression of organophosphate hydrolase in the filamentous fungus gliocladium virens.the broad-spectrum organophosphate hydrolase (oph; ec encoded by the organophosphate-degrading gene (opd) from pseudomonas diminuta mg and flavobacterium sp. atcc 27551 possesses capabilities of both p-o bond hydrolysis (e.g. paraoxon) and p-f bond hydrolysis [e.g. sarin and diisopropylfluorophosphate (dfp)]. in the present study a 9.4-kb plasmid, pcl1, was used to transform the saprophytic fungus gliocladium virens. pcl1 was derived from pjs294 by placing the fungal promoter (prom1) fr ...19947764970
development of a transformation system for trichoderma longibrachiatum and its use for constructing multicopy transformants for the egl1 efficient transformation system for the fungus trichoderma longibrachiatum has been developed. transformation was obtained both by electroporation and polyethyleneglycol treatment, using a plasmid carrying the escherichia coli hygromycin b phosphotransferase gene as a dominant selectable marker. the transformation frequency was 0.5 to 5 transformants/micrograms plasmid dna. transformation normally occurred by tandem integration of the transforming dna. a high percentage of the transformants w ...19947765105
alcohol metabolism. 19947765123
inorganic nitrogen assimilation: molecular aspects. 19947765124
control of metabolic flux in the shikimate and quinate pathways. 19947765125
the purine degradation pathway, genetics, biochemistry and regulation. 19947765126
the proline utilisation pathway, history and beyond. 19947765127
regulation of acetamide utilization. 19947765128
sulphur metabolism. 19947765129
the early history. 19947765130
nitrogen metabolite repression. 19947765131
aspergillus nidulans as an experimental organism. 19947765132
carbon catabolite repression. 19947765133
regulation of gene expression by oxygen, phosphorus and ph. 19947765134
genetic regulation of conidiation. 19947765135
sexual sporulation. 19947765136
control of cell growth. 19947765137
ribosomes. 19947765138
mitochondria. 19947765139
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