| identification of claisen cyclase domain in fungal polyketide synthase wa, a naphthopyrone synthase of aspergillus nidulans. | based on the homology with fatty acid synthases and bacterial polyketide synthases (pkss), thioesterase domains have been assigned at the c-terminus regions of fungal iterative type i pkss. we previously overexpressed aspergillus nidulans wa pks gene in a heterologous fungal host and identified it to encode a heptaketide naphthopyrone synthase. in addition, expression of c-terminus-modified wa pks gave heptaketide isocoumarins suggesting that the c-terminus region of wa pks is involved in the cy ... | 2001 | 11251292 |
| heterologous transposition in aspergillus nidulans. | aspergillus nidulans is one of the model ascomycete fungi. transposition events have never been described in this organism. we have determined that this organism has at least 13 copies of a fot1-related element. these copies are transcribed, non-methylated and polymorphic in various wild isolates. in spite of this, we have failed to isolate transposon insertions when the resident niad gene is used as a transposon trap. this contrasts with the situation described previously in fusarium oxysporum. ... | 2001 | 11251848 |
| characterization of the reverse transsulfuration gene mecb of acremonium chrysogenum, which encodes a functional cystathionine-gamma-lyase. | in acremonium chrysogenum, biosynthesis of cysteine for the formation of cephalosporin has been proposed to occur through the reverse transsulfuration pathway. a gene, named mecb, has been cloned from an a. chrysogenum c10 genomic library in lambdaembl3-ble. the cloned dna fragment encodes a protein of 423 amino acids with a deduced molecular mass of 45 kda that shows great similarity to cystathionine-gamma-lyases from saccharomyces cerevisiae and other eukaryotic organisms. the protein was show ... | 2001 | 11254121 |
| expression of pleurotus eryngii aryl-alcohol oxidase in aspergillus nidulans: purification and characterization of the recombinant enzyme. | aryl-alcohol oxidase (aao) is an extracellular flavoenzyme involved in lignin biodegradation by some white-rot fungi. the enzyme catalyzes the extracellular oxidation of aromatic alcohols to the corresponding aldehydes. the electron acceptor is molecular oxygen yielding h(2)o(2) as the product. herein we describe, for the first time, the expression of aao from pleurotus eryngii in the ascomycete aspergillus nidulans. the activity of the recombinant enzyme in a. nidulans cultures is much higher t ... | 2001 | 11257513 |
| rcoa has pleiotropic effects on aspergillus nidulans cellular development. | aspergillus nidulans rcoa encodes a member of the wd repeat family of proteins. the rcoa protein shares sequence similarity with other members of this protein family, including the saccharomyces cerevisiae tup1p and neurospora crassa rco1. tup1p is involved in negative regulation of an array of functions including carbon catabolite repression. rco1 functions in regulating pleiotropic developmental processes, but not carbon catabolite repression. in a. nidulans, deletion of rcoa (deltarcoa), a re ... | 2001 | 11260466 |
| genetically engineered peptide fusions for improved protein partitioning in aqueous two-phase systems. effect of fusion localization on endoglucanase i of trichoderma reesei. | genetic engineering has been used for fusion of the peptide tag, trp-pro-trp-pro, on a protein to study the effect on partitioning in aqueous two-phase systems. as target protein for the fusions the cellulase, endoglucanase i (endo-1,4-beta-dglucan-4-glucanohydrolase, ec 3.2.1.4, egi, cel7b) of trichoderma reesei was used. for the first time a glycosylated two-domain enzyme has been utilized for addition of peptide tags to change partitioning in aqueous two-phase systems. the aim was to find an ... | 2001 | 11261722 |
| differential chemical labeling of the alcr dna-binding domain from aspergillas nidulans versus its complex with a 16-mer dna target: identification of an essential tryptophan involved in the recognition and the interaction with the nucleic acid. | dna binding of the ethanol regulon transcription factor alcr from aspergillus nidulans was shown to involve a consensus basic region as in the other zinc cluster proteins. however, additional interactions between some residues and dna were suspected, among which were a hypothetic hydrophobic interaction between trp45 and the t residue of the consensus tgcgg sequence. in the present study, the differential chemical labeling of both the free protein and the protein/dna complex showed significantly ... | 2001 | 11266598 |
| regulation of the aspergillus nidulans hisb gene by histidine starvation. | the hisb gene of the filamentous fungus aspergillus nidulans encodes imidazole glycerol-phosphate dehydratase (e.c. 4.2.1.19), which catalyses the seventh enzymatic step in histidine biosynthesis. the gene was isolated and its deduced peptide sequence of 247 amino acids showed up to 54% identity with the igpd enzymes of organisms comprising all three kingdoms. expression of hisb cdna in a saccharomyces cerevisiae his3delta mutant strain functionally complemented the growth phenotype under histid ... | 2001 | 11270573 |
| polarity-defective mutants of aspergillus nidulans. | we have identified two polarity-defective (pod) mutants in aspergillus nidulans from a collection of heat-sensitive lethal mutants. at restrictive temperature, these mutants are capable of nuclear division but are unable to establish polar hyphal growth. we cloned the two pod genes by complementation of their heat-sensitive lethal phenotypes. the libraries used to clone the pod genes are under the control of the bidirectional niad and niia promoters. complementation of the pod mutants is depende ... | 2000 | 11273680 |
| lis1 and dynein motor function in neuronal migration and development. | | 2001 | 11274050 |
| transposon impala, a novel tool for gene tagging in the rice blast fungus magnaporthe grisea. | impala, a tc1-mariner transposable element from fusarium oxysporum, was introduced into the rice blast fungus magnaporthe grisea to develop transposon-based insertional mutagenesis. a construct (pnil160) containing an autonomous impala copy inserted in the promoter of niad encoding aspergillus nidulans nitrate reductase was introduced by transformation into a m. grisea nitrate reductase-deficient mutant. impala excision was monitored by restoration of prototrophy for nitrate. southern analysis o ... | 2001 | 11277428 |
| expression of the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum is regulated by the global nitrogen response factor nrf1. | here we describe the role of the cladosporium fulvum nitrogen response factor 1 (nrf1) gene in regulation of the expression of avirulence gene avr9 and virulence on tomato. the nrf1 gene, which was isolated by a polymerase chain reaction-based strategy, is predicted to encode a protein of 918 amino acid residues. the protein contains a putative zinc finger dna-binding domain that shares 98% amino acid identity with the zinc finger of the major nitrogen regulatory proteins area and nit2 of asperg ... | 2001 | 11277429 |
| regulation of hishf transcription of aspergillus nidulans by adenine and amino acid limitation. | the hishf gene of aspergillus nidulans encodes imidazole-glycerole-phosphate (igp) synthase, consisting of a glutamine amidotransferase and a cyclase domain. the enzyme catalyzes the fifth and sixth steps of histidine biosynthesis, which results in an intermediate of the amino acid and an additional intermediate of purine biosynthesis. an a. nidulans hishf cdna complemented a saccharomyces cerevisiae his7delta strain and escherichia coli hish and hisf mutant strains. the genomic dna encoding the ... | 2001 | 11277623 |
| adhii in aspergillus nidulans is induced by carbon starvation stress. | in aspergillus nidulans there are three nad(+)-dependent alcohol dehydrogenases (adhs) that are capable of utilizing ethanol as a substrate. adhi is the physiological enzyme of ethanol catabolism and adhiii is induced under conditions of anaerobiosis. the physiological role of adhii (structural gene alcb) is unknown. we have measured beta-galactosidase in a transformant with an alcb::lacz fusion and have shown that alcb is maximally expressed under conditions of carbon starvation. the behavior o ... | 2001 | 11277624 |
| genetic and physical mapping of two centromere-proximal regions of chromosome iv in aspergillus nidulans. | chromosome iv is the smallest chromosome of aspergillus nidulans. the centromere-proximal portion of the chromosome was mapped physically using overlapping clones of a cosmid genomic library. two contiguous segments of a physical map, based on restriction mapping of cosmid clones, were generated, together covering more than 0.4 mb dna. a reverse genetic mapping approach was used to establish a correlation between physical and genetic maps; i.e., marker genes were integrated into physically mappe ... | 2001 | 11277625 |
| genetic engineering of the trichoderma reesei endoglucanase i (cel7b) for enhanced partitioning in aqueous two-phase systems containing thermoseparating ethylene oxide--propylene oxide copolymers. | endoglucanases (endo-1,4-beta-d-glucan-4-glucanohydrolase, ec 3.2.1.4) are industrially important enzymes. in this study endoglucanase i (egi or cel7b) of the filamentous fungi trichoderma reesei has been genetically engineered to investigate the influence of tryptophan rich peptide extensions (tags) on partitioning in an aqueous two-phase model system. egi is a two-domain enzyme and is composed of a n-terminal catalytic domain and a c-terminal cellulose binding domain, separated by a linker. th ... | 2001 | 11278040 |
| comparison of the e-test with the nccls m38-p method for antifungal susceptibility testing of common and emerging pathogenic filamentous fungi. | the national committee for clinical laboratory standards (nccls) m38-p method describes standard parameters for testing the fungistatic antifungal activities (mics) of established agents against filamentous fungi (molds). the present study evaluated the in vitro fungistatic activities of itraconazole and amphotericin b by the e-test and the nccls m38-p microdilution method against 186 common and emerging pathogenic molds (123 isolates of aspergillus spp. [five species], 16 isolates of fusarium s ... | 2001 | 11283057 |
| functional characterization of a maize purine transporter by expression in aspergillus nidulans. | we have characterized the function of leaf permease1 (lpe1), a protein that is necessary for proper chloroplast development in maize, by functional expression in the filamentous fungus aspergillus nidulans. the choice of this ascomycete was dictated by the similarity of its endogenous purine transporters to lpe1 and by particular genetic and physiological features of purine transport and metabolism in a. nidulans. when lpe1 was expressed in a purine transport-deficient a. nidulans strain, the ca ... | 2001 | 11283348 |
| regulative fine-tuning of the two novel dahp isoenzymes arofp and arogp of the filamentous fungus aspergillus nidulans. | two novel genes, arof and arog, from the filamentous fungus aspergillus nidulans were isolated and the regulative fine-tuning between the encoded, differentially regulated 3-deoxy-d-arabino-heptulosonate-7-phosphate (dahp) synthases was analyzed. a wide range of dahp synthase isoenzymes of various organisms are known, but only a few have been characterized further. dahp synthases (ec 4.1.2.15) catalyze the first committed step of the shikimate pathway, which is a putative target for anti-weed dr ... | 2001 | 11285739 |
| the aspergillus nidulans homoaconitase gene lysf is negatively regulated by the multimeric ccaat-binding complex ancf and positively regulated by gata sites. | in beta-lactam-antibiotic-producing fungi, such as aspergillus (emericella) nidulans, l-alpha-aminoadipic acid is the branching point of the lysine and penicillin biosynthesis pathways. to obtain a deeper insight into the regulation of lysine biosynthesis genes, the regulation of the a. nidulans lysf gene, which encodes homoaconitase, was studied. band-shift assays indicated that the a. nidulans multimeric ccaat-binding complex ancf binds to two of four ccaat motifs present in the lysf promoter ... | 2001 | 11285740 |
| histone acetyltransferase complexes stabilize swi/snf binding to promoter nucleosomes. | to investigate the function of swi/snf in site-specific chromatin remodeling at promoters, we have used a purified system to analyze its distribution, function, and retention following recruitment by a sequence-specific transcription activator. activator recruitment of swi/snf bound the complex to promoter proximal nucleosomes and led to localized nucleosome disruption. however, retention of swi/snf on the promoter required either the continued binding of the transcription activator or acetylate ... | 2001 | 11290320 |
| physical mapping with automatic capture of hybridization data. | motivation: contig maps are a type of physical map that show the native order of a set of overlapping genomic clones. overlaps between clones can be detected by finding common sequences using a number of experimental protocols including hybridization of probes. all current mapping algorithms of which we are aware require that hybridizations be scored using a fixed number of discrete values (typically 0/1 or high/medium/low). when hybridization data is captured automatically using digital equipme ... | 2001 | 11294786 |
| cloning of two pectate lyase genes from the marine antarctic bacterium pseudoalteromonas haloplanktis strain ant/505 and characterization of the enzymes. | a marine antarctic psychrotolerant bacterium (strain ant/505), isolated from sea ice-covered surface water from the southern ocean, showed pectinolytic activity on citrus pectin agar. the sequencing of the 16s rrna of isolate ant/505 indicates a taxonomic affiliation to pseudoalteromonas haloplanktis. the supernatant of this strain showed three different pectinolytic activities after growth on citrus pectin. by activity screening of a genomic dna library of isolate ant/505 in escherichia coli, t ... | 2001 | 11302501 |
| the aspergillus nidulans gata transcription factor gene areb encodes at least three proteins and features three classes of mutation. | in aspergillus nidulans, the principal transcription factor regulating nitrogen metabolism, area, belongs to the gata family of dna-binding proteins. in seeking additional gata factors, we have cloned areb, which was originally identified via a genetic screen for suppressors of area loss-of-function mutations. based on our analysis, areb is predicted to encode at least three distinct protein products. these arise from the use of two promoters, differential splicing and translation initiating at ... | 2001 | 11309119 |
| characterization of the amyr gene encoding a transcriptional activator for the amylase genes in aspergillus nidulans. | the aspergillus nidulans amyr gene and its cdna were cloned and sequenced. the genomic gene comprised 2,092 bp, interrupted by two short introns, and encoded a cys-6 zinc transcriptional activator (amyr) of 662 amino acid residues with a calculated molecular mass of 72,862 da. disruption of the amyr gene caused defects in the utilization of maltose and starch and abolished expression of the taag2 gene encoding a. oryzae taka-amylase a, which is inducibly and abundantly expressed in the wild-type ... | 2001 | 11318101 |
| a type 2a protein phosphatase gene from aspergillus nidulans is involved in hyphal morphogenesis. | a pcr-based approach, using degenerate oligonucleotide primers, was used to isolate fragments of two genes encoding type 2a protein phosphatases from the filamentous fungus, aspergillus nidulans. the complete genomic sequence of one of these genes, ppha, was isolated and characterised. the ppha gene was predicted to encode a 329-residue protein which is about 85% identical to mammalian protein phosphatase 2a. ectopic expression of the wild-type ppha+ gene slightly inhibited growth in some transf ... | 2001 | 11318104 |
| isoenzyme multiplicity and characterization of recombinant manganese peroxidases from ceriporiopsis subvermispora and phanerochaete chrysosporium. | we expressed cdnas coding for manganese peroxidases (mnps) from the basidiomycetes ceriporiopsis subvermispora (mnp1) and phanerochaete chrysosporium (h4) under control of the alpha-amylase promoter from aspergillus oryzae in aspergillus nidulans. the recombinant proteins (rmnp1 and rh4) were expressed at similar levels and had molecular masses, both before and after deglycosylation, that were the same as those described for the mnps isolated from the corresponding parental strains. isoelectric ... | 2001 | 11319083 |
| characterization of an echinocandin b-producing strain blocked for sterigmatocystin biosynthesis reveals a translocation in the stcw gene of the aflatoxin biosynthetic pathway. | echinocandin b (ecb), a lipopolypeptide used as a starting material for chemical manufacture of the anti-candida agent ly303366, is produced by fermentation using a strain of aspergillus nidulans. in addition to ecb, the wild-type strain also produces a significant level of sterigmatocystin (st), a potent carcinogen structurally related to the aflatoxins. characterization of a mutant designated a42355-oc-1 (oc-1), which is blocked in st biosynthesis, was the result of a chromosomal translocation ... | 2000 | 11320421 |
| dimerization and folding of lc8, a highly conserved light chain of cytoplasmic dynein. | cytoplasmic dynein is a multisubunit atpase that transforms chemical energy into motion along microtubules. lc8, a 10 kda light chain subunit of the dynein complex, is highly conserved with 94% sequence identity between drosophila and human. the precise function of this protein is unknown, but its ubiquitous expression and conservation suggest a critical role in the function of the dynein motor complex. we have overexpressed lc8 from drosophila melanogaster and characterized its dimerization and ... | 2001 | 11327818 |
| isolation and characterization of a symbiosis-regulated ras from the ectomycorrhizal fungus laccaria bicolor. | ectomycorrhizae formed by the symbiotic interaction between ectomycorrhizal fungi and plant roots play a key role in maintaining and improving the health of a wide range of plants. mycorrhizal initiation, development, and functional maintenance involve morphological changes that are mediated by activation and suppression of several fungal and plant genes. we identified a gene, lbras, in the ectomycorrhizal fungus laccaria bicolor that belongs to the ras family of genes, which has been shown in o ... | 2001 | 11332726 |
| molecular cloning of palbh, a mammalian homologue of the aspergillus atypical calpain palb. | a mammalian homologue of the aspergillus atypical calpain palb, palbh, was identified and its cdna sequences were determined in human and mouse. the palbh mrna was expressed nearly ubiquitously throughout mammalian tissues. when expressed in cos cells, palbh was enriched in the nucleus, suggesting its role is distinct from that of conventional calpains. | 2001 | 11342116 |
| the nuclear migration gene nudc and human hematopoiesis. | the filamentous fungus aspergillus nidulans nudc (nuclear distribution c) gene is required for movement of nuclei following mitosis and for normal colony growth. it is highly conserved, structurally and functionally, throughout most of evolution. the human homolog, called hnudc, has been cloned and has an important role in cell proliferation. in hematopoiesis, hnudc is highly expressed in early hematopoietic precursors and declines during normal differentiation. stimulation of proliferation of t ... | 2000 | 11342328 |
| the cdc42 homolog of the dimorphic fungus penicillium marneffei is required for correct cell polarization during growth but not development. | the opportunistic human pathogenic fungus penicillium marneffei is dimorphic and is thereby capable of growth either as filamentous multinucleate hyphae or as uninucleate yeast cells which divide by fission. the dimorphic switch is temperature dependent and requires regulated changes in morphology and cell shape. cdc42p is a rho family gtpase which in saccharomyces cerevisiae is required for changes in polarized growth during mating and pseudohyphal development. cdc42p homologs in higher organis ... | 2001 | 11344153 |
| airborne fungal ecological niche determination as one of the possibilities for indirect mycotoxin risk assessment in indoor air. | based on the microbiological analysis of air samples from occupied spaces, some possibilities for indirect risk assessment of mycotoxin-related health problems are proposed. airborne fungi could be classified on the basis of the relationship between the two environmental factors and their combinations, i.e., temperature and water requirements (water activity aw). one type involves three different groups of molds, selected on the basis of the quantitative and qualitative information about the abi ... | 2001 | 11345539 |
| a comprehensive characterization of a group ib intron and its encoded maturase reveals that protein-assisted splicing requires an almost intact intron rna. | the group i intron (ancob) of the mitochondrial apocytochrome b gene from aspergillus nidulans encodes a bi-functional maturase protein that is also a dna endonuclease. although the ancob intron self-splices, the encoded maturase protein greatly facilitates splicing, in part, by stabilizing rna tertiary structure. to determine their role in self-splicing and in protein-assisted splicing, several peripheral rna sub-domains in the 313 nucleotide intron were deleted (p2, p9, p9.1) or truncated (p5a ... | 2001 | 11350164 |
| the aspergillus nidulans pyrg89 mutation alters glycosylation of secreted acid phosphatase. | the glycosylation level of the paca-encoded acid phosphatase secreted by aspergillus nidulans was reduced in strains pabaa1 pyroa4and pabaa1 pyroa4 pyrg89, compared to strains carrying these mutations singly. the molecular mass of the enzyme secreted by the triple mutant grown at ph 5.0 was 105 and 45 kda as determined by exclusion chromatography and sds-page, respectively. in contrast, the pabaa1 strain secreted acid phosphatases of 119 and 62 kda. the enzyme also had an altered electrophoretic ... | 2001 | 11352532 |
| genetic connection between fatty acid metabolism and sporulation in aspergillus nidulans. | in the ascomycete fungus aspergillus nidulans, the ratio of conidia (asexual spores) to ascospores (sexual spores) is affected by linoleic acid moieties including endogenous sporogenic factors called psi factors. deletion of odea (delta odea), encoding a delta-12 desaturase that converts oleic acid to linoleic acid, resulted in a strain depleted of polyunsaturated fatty acids (18:2 and 18:3) but increased in oleic acid (18:1) and total percent fatty acid content. linoleic acid-derived psi factor ... | 2001 | 11352908 |
| bimd/spo76 is at the interface of cell cycle progression, chromosome morphogenesis, and recombination. | bimd of aspergillus nidulans belongs to a highly conserved protein family implicated, in filamentous fungi, in sister-chromatid cohesion and dna repair. we show here that bimd is chromosome associated at all stages, except from late prophase through anaphase, during mitosis and meiosis, and is involved in several aspects of both programs. first, bimd(+) function must be executed during s through m. second, in bimd6 germlings, mitotic nuclear divisions and overall cellular program occur more rapi ... | 2001 | 11353817 |
| enzymatic properties of the highly thermophilic and alkaline pectate lyase pel-4b from alkaliphilic bacillus sp. strain p-4-n and the entire nucleotide and amino acid sequences. | we cloned two genes for alkaline pectate lyase, pel-4a and pel-4b, from alkaline pectinase-producing alkaliphilic bacillus sp. strain p-4-n. the pel-4b gene product pel-4b was purified to homogeneity and characterized. the purified enzyme had an isoelectric point of ph 9.6 and a molecular mass of 35 kda, values close to those of the pel-4a gene product pel-4a. the ph and temperature optima for activity were as high as 11.5 and 70 degrees c, respectively, which are the highest among the pectate l ... | 2001 | 11354456 |
| a pcl-like cyclin of aspergillus nidulans is transcriptionally activated by developmental regulators and is involved in sporulation. | the filamentous fungus aspergillus nidulans reproduces asexually through the formation of spores on a multicellular aerial structure, called a conidiophore. a key regulator of asexual development is the tfiiia-type zinc finger containing transcriptional activator bristle (brla). besides brla, the transcription factor abaa, which is located downstream of brla in the developmental regulation cascade, is necessary to direct later gene expression during sporulation. we isolated a new developmental m ... | 2001 | 11359914 |
| sensitivity to camptothecin in aspergillus nidulans identifies a novel gene, scaa+, related to the cellular dna damage response. | the anti-cancer drug camptothecin targets eukaryotic dna topoisomerase i by trapping the covalent complex formed between the catalytically active enzyme and dna. we are interested in identifying factors, other than topoisomerase i, that are involved in mediating cellular sensitivity to camptothecin. to this end, we have isolated eighteen mutants that are sensitive to camptothecin (sca) in the filamentous fungus aspergillus nidulans and characterised one of them, sca299. the mutant sca299 is hype ... | 2001 | 11361337 |
| cloning and characterization of aspergillus nidulans vpsa gene which is involved in vacuolar biogenesis. | in saccharomyces cerevisiae, vacuoles play very important roles in ph and osmotic regulation, protein degradation and storage of amino acids, small ions as well as polyphosphates. in filamentous fungi, however, little is known about vacuolar functions at a molecular level. in this paper, we report the isolation of the vpsa gene from the filamentous fungus aspergillus nidulans as a homologue of the vps1 gene of s. cerevisiae which encodes a dynamin-related protein. the vpsa gene encodes a polypep ... | 2001 | 11368897 |
| the aspergillus cytoplasmic dynein heavy chain and nudf localize to microtubule ends and affect microtubule dynamics. | cytoplasmic dynein is a multisubunit, minus end-directed microtubule motor that uses dynactin as an accessory complex to perform various in vivo functions including vesicle transport, spindle assembly, and nuclear distribution [1]. we previously showed that in the filamentous fungus aspergillus nidulans, a gfp-tagged cytoplasmic dynein heavy chain (nuda) forms comet-like structures that exhibited microtubule-dependent movement toward and back from the hyphal tip [2]. here we demonstrate that ano ... | 2001 | 11369237 |
| identification of aspergillus fumigatus and related species by nested pcr targeting ribosomal dna internal transcribed spacer regions. | aspergillus fumigatus is the most common species that causes invasive aspergillosis. in order to identify a. fumigatus, partial ribosomal dna (rdna) from two to six strains of five different aspergillus species was sequenced. by comparing sequence data from genbank, we designed specific primer pairs targeting rdna internal transcribed spacer (its) regions of a. fumigatus. a nested pcr method for identification of other a. fumigatus-related species was established by using the primers. to evaluat ... | 2001 | 11376067 |
| molecular characterization of a blue-copper laccase, tila, of aspergillus nidulans. | laccases are blue-copper enzymes, which oxidize phenolic substrates and thereby reduce molecular oxygen. they are widespread within fungi and are involved in lignin degradation or secondary metabolism such as pigment biosynthesis. many fungi contain several laccases, not all of whose functions are known. in aspergillus nidulans one, ya, is expressed during asexual development and converts a yellow precursor to the green pigment. we identified a second laccase gene, which encodes a 66.3-kda prote ... | 2001 | 11377869 |
| molecular cloning of cgra, the gene encoding the aspergillus nidulans ortholog of saccharomyces cerevisiae cgr1. | saccharomyces cerevisiae cgr1 encodes a 120-amino acid protein with a predominant nucleolar localization. in this study we report the identification and cloning of the ortholog, cgra, from aspergillus nidulans. the cgra gene is comprised of three exons on a. nidulans chromosome 7. the cdna contains a single open reading frame (orf) that would encode a protein of 114 amino acids with 44% sequence identity to yeast cgr1p. a plasmid expressing cgra complemented the impaired growth phenotype of a ye ... | 2001 | 11381331 |
| effect of the raw extracts of arthrinium strains (hyphomycetes, dematiaceae) on the growth of some deleterious fungi in poultry feed. | in previous work the authors have shown that some species of the arthrinium genus are characterized by being able to produce secondary metabolites with antibiotic activity. the aim of this study was to evaluate the effect of raw extracts of the growth of three different arthrinium strains against aspergillus flavus, aspergillus nidulans, fusarium moniliforme and penicillium purpurogenum when they were present in poultry feed. the results showed that the extracts reduced the growth of aspergillus ... | 2001 | 11393747 |
| a new sterigmatocystin-producing emericella variant from agricultural desert soils. | an unusual, sterigmatocystin-producing taxon with characteristics of both emericella nidulans (anamorph aspergillus nidulans) and emericella rugulosa (anamorph aspergillus rugulovalvus, formerly a. rugulosus) was isolated repeatedly during a mycofloral survey of desert cotton field soils where aflatoxin is a chronic problem. members of this taxon had ascospores with smooth convex walls like e. nidulans but grew slowly like e. rugulosa; moreover, they were similar to an industrial echinocandin b- ... | 2001 | 11403392 |
| the aspergillus nidulans mete gene is regulated by a second system independent from sulphur metabolite repression. | mutations in the aspergillus nidulans mete gene lead to requirement for o-acetylhomoserine. the gene was cloned by complementation of the mete31 mutation. the coding sequence was found to be interrupted by two introns of 66 and 50 bp, respectively. mete codes for a peptide of 489 amino acids which belongs to the family of homoserine o-acetyltransferases and a well-defined superfamily of alpha/beta hydrolases. transcription of the mete gene is strongly up-regulated by a severe limitation of methi ... | 2001 | 11406274 |
| isolation and characterization of sexual sporulation mutants of aspergillus nidulans. | for the genetic dissection of sexual sporulation in aspergillus nidulans, we started a collection of ascosporeless mutants. after mutagenization of conidiospores with high doses of uv, we isolated 20 mutants with defects in ascospore formation. we crossed these mutants in two successive rounds with the wild-type strain. eighteen of the 20 isolated mutants produced progeny with the original mutant phenotype in these crosses, and these mutants were further analyzed. all 18 analyzed mutations were ... | 2001 | 11407883 |
| aohapb, aohapc and aohape, subunits of the aspergillus oryzae ccaat-binding complex, are functionally interchangeable with the corresponding subunits in aspergillus nidulans. | two genes, aohapb and aohape, encoding subunits of the aspergillus oryzae ccaat-binding complex were cloned and sequenced. the polypeptides encoded by aohapb and aohape were expressed in escherichia coli and used to reconstitute a dna-binding complex with recombinant aohapc. the dna-binding activity was observed only in the presence of all three subunits, indicating that aohapb, aohape and aohapc are essential for ccaat-binding. furthermore, introduction of the aohapb, aohapc and aohape genes in ... | 2001 | 11409179 |
| phenotypic and genotypic characterization of reference strains of the genus aspergillus. | twenty-five culture collection strains from four aspergillus species (a. fumigatus n = 8, a. flavus n = 8, a. niger n = 4, a. nidulans n = 5) were characterized by four methods: (i) determination of patterns in an assimilation assay; (ii) protein pattern of whole mycelial cell lysates in the sodium dodecyl sulphate (sds)-polyacrylamide gel electrophoresis (page); (iii) reactivity of a pool serum obtained from cystic fibrosis patients with mycelial lysates in the immunoblot; and (iv) random ampli ... | 2001 | 11413925 |
| resistance to itraconazole in aspergillus nidulans and aspergillus fumigatus is conferred by extra copies of the a. nidulans p-450 14alpha-demethylase gene, pdma. | triazoles selectively inhibit the cytochrome p-450-dependent c-14 lanosterol alpha-demethylase (p-450 14 alpha dm), a key enzyme in ergosterol biosynthesis in fungi. to investigate mechanisms of triazole resistance in a mould, we used aspergillus nidulans, a genetically amenable model fungus closely related to more pathogenic members of the genus. we selected for genes that would give resistance to itraconazole following transformation with a high copy genomic library of a. nidulans. in all the ... | 2001 | 11418514 |
| site-directed mutagenesis of proline-285 to leucine in cephalosporium acremonium isopenicillin-n-synthase affects catalysis and increases soluble expression at higher temperatures. | the conversion of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) to isopenicillin n is dependant on the catalytic action of isopenicillin n-synthase (ipns), an important enzyme in the penicillin and cephalosporin biosynthetic pathway. one of the amino acid residues suggested by the aspergillus nidulans ipns crystal structure for interaction with the valine isopropyl group of acv is proline-283. site-directed mutagenesis of the corresponding proline-285 to leucine in cephalosporium acremo ... | 2001 | 11421458 |
| 2-methylisocitrate lyases from the bacterium escherichia coli and the filamentous fungus aspergillus nidulans: characterization and comparison of both enzymes. | in escherichia coli and aspergillus nidulans, propionate is oxidized to pyruvate via the methylcitrate cycle. the last step of this cycle, the cleavage of 2-methylisocitrate to succinate and pyruvate is catalysed by 2-methylisocitrate lyase. the enzymes from both organisms were assayed with chemically synthesized threo-2-methylisocitrate; the erythro-diastereomer was not active. 2-methylisocitrate lyase from e. coli corresponds to the prpb protein of the prp operon involved in propionate oxidati ... | 2001 | 11422389 |
| identification of two different 14-alpha sterol demethylase-related genes (cyp51a and cyp51b) in aspergillus fumigatus and other aspergillus species. | two cyp51-related genes (cyp51a and cyp51b) encoding 14-alpha sterol demethylase-like enzymes were identified in the opportunistic human pathogen aspergillus fumigatus. pcr amplification using degenerate oligonucleotides based on conserved areas of cytochrome p450 demethylases of other filamentous fungi and yeasts allowed the cloning and sequencing of two different homologue genes in a. fumigatus. southern analysis confirmed that both genes hybridized to distinct genomic loci and that both are r ... | 2001 | 11427550 |
| trehalose is required for the acquisition of tolerance to a variety of stresses in the filamentous fungus aspergillus nidulans. | trehalose is a non-reducing disaccharide found at high concentrations in aspergillus nidulans conidia and rapidly degraded upon induction of conidial germination. furthermore, trehalose is accumulated in response to a heat shock or to an oxidative shock. the authors have characterized the a. nidulans tpsa gene encoding trehalose-6-phosphate synthase, which catalyses the first step in trehalose biosynthesis. expression of tpsa in a saccharomyces cerevisiae tps1 mutant revealed that the tpsa gene ... | 2001 | 11429462 |
| cloning and characterization of the cpya gene encoding intracellular carboxypeptidase from aspergillus nidulans. | carboxypeptidase y (cpy) has been used as a maker enzyme for investigations on intracellular transport of vacuolar proteins and on vacuolar biogenesis in saccharomyces cerevisiae. we describe the cloning and characterization of the cpy homologue encoding gene (cpya) from the filamentous fungus aspergillus nidulans. the cpya gene has one intron and encodes a protein with 552 amino acids containing a putative signal sequence and pro-sequence. the predicted cpya protein is highly similar in sequenc ... | 2001 | 11440134 |
| carbon catabolite repression in aspergillus nidulans involves deubiquitination. | the best studied role of ubiquitination is to mark proteins for destruction by the proteasome but, in addition, it has recently been shown to promote macromolecular assembly and function, and alter protein function, thus playing a regulatory role distinct from protein degradation. deubiquinating enzymes, the ubiquitin-processing proteases (ubps) and the ubiquitin carboxy-terminal hydrolases (uchs), remove ubiquitin from ubiquitinated substrates. we show here that the creb gene involved in carbon ... | 2001 | 11442830 |
| alanine-scanning mutagenesis of aspergillus gamma-tubulin yields diverse and novel phenotypes. | we have created 41 clustered charged-to-alanine scanning mutations of the mipa, gamma-tubulin, gene of aspergillus nidulans and have created strains carrying these mutations by two-step gene replacement and by a new procedure, heterokaryon gene replacement. most mutant alleles confer a wild-type phenotype, but others are lethal or conditionally lethal. the conditionally lethal alleles exhibit a variety of phenotypes under restrictive conditions. most have robust but highly abnormal mitotic spind ... | 2001 | 11452008 |
| the isda gene is necessary for sexual development inhibition by a salt in aspergillus nidulans. | using one of 17 expressed sequence tags (ests) previously identified as specific to the late sexual developmental (lsd) stage of aspergillus nidulans, a gene for the subject est was isolated. the determined dna sequences revealed an open reading frame encoding a 356 amino acid polypeptide which does not share a sequence similarity to previously identified genes or proteins. the isolated gene was named lsda (late sexual development), since it was expressed abundantly at the lsd stage. the lsda ge ... | 2001 | 11453253 |
| characterization of the role of the flug protein in asexual development of aspergillus nidulans. | we showed previously that a deltaflug mutation results in a block in aspergillus nidulans asexual sporulation and that overexpression of flug activates sporulation in liquid-submerged culture, a condition that does not normally support sporulation of wild-type strains. here we demonstrate that the entire n-terminal region of flug ( approximately 400 amino acids) can be deleted without affecting sporulation, indicating that flug activity resides in the c-terminal half of the protein, which bears ... | 2001 | 11454752 |
| functional expression and cellular localization of a green fluorescent protein-tagged proline transporter in aspergillus nidulans. | the prnb protein is a highly specific proline transporter that belongs to an amino acid transporter family conserved in both prokaryotes and eukaryotes. in this work, we detected and analyzed the cellular localization of prnb in vivo by means of green fluorescent protein (gfp) fusions. several prnb-gfp gene fusions, driven by prnb native promoter sequences, were constructed and targeted to the genomic locus of a prnb null mutant. chimeric proteins containing gfp fused to the c terminus of prnb t ... | 2001 | 11456464 |
| functional analysis of tama, a coactivator of nitrogen-regulated gene expression in aspergillus nidulans. | the tam a gene of aspergillus nidulans encodes a 739-amino acid protein with similarity to uga35p/dal81p/durlp of saccharomyces cerevisiae. it has been proposed that tama functions as a co-activator of area, the major nitrogen regulatory protein in a. nidulans. because area functions as a transcriptional activator under nitrogen-limiting conditions, we investigated whether tama was also present in the nucleus. we found that a gfp-tama fusion protein was predominantly localised to the nucleus in ... | 2001 | 11459183 |
| myosin i mutants with only 1% of wild-type actin-activated mgatpase activity retain essential in vivo function(s). | the single class i myosin (myoa) of aspergillus nidulans is essential for hyphal growth. it is generally assumed that the functions of all myosins depend on their actin-activated mgatpase activity. here we show that myoa mutants with no more than 1% of the actin-activated mgatpase activity of wild-type myoa in vitro and no detectable in vitro motility activity can support fungal cell growth, albeit with a delay in germination time and a reduction in hyphal elongation. from these and other data, ... | 2001 | 11459943 |
| the aspergillus nidulans carnitine carrier encoded by the acuh gene is exclusively located in the mitochondria. | the location of the aspergillus nidulans carnitine/acyl-carnitine carrier (acuh) was studied. acuh with a his-tag at its n-terminus was over-expressed in escherichia coli and purified by ni(2+) affinity chromatography. the purified protein was utilised to raise polyclonal antibodies which were characterised by western blotting. for localisation studies a. nidulans t1 strain, that contains the acuh gene under control of the strong promoter alca(p), was derived. results obtained demonstrate the ex ... | 2001 | 11470361 |
| development of a homologous transformation system for the opportunistic human pathogen aspergillus fumigatus based on the sc gene encoding atp sulfurylase. | the development of a homologous transformation system for the opportunistic human pathogenic fungus aspergillus fumigatus is described. the system is based on the sc gene encoding atp sulfurylase. several a. fumigatus sc mutant strains were readily isolated by strong selection for selenate resistance. the coding region plus upstream and downstream regulatory sequences of the a. fumigatus sc gene were cloned by inverse pcr and then sequenced. sequencing of the sc cdna revealed the presence of fiv ... | 2001 | 11479709 |
| a single gene produces mitochondrial, cytoplasmic, and peroxisomal nadp-dependent isocitrate dehydrogenase in aspergillus nidulans. | nadp-dependent isocitrate dehydrogenase enzymes catalyze the decarboxylation of isocitrate to 2-oxoglutarate accompanied by the production of nadph. in mammals two different genes encode mitochondrial and cytoplasmic/peroxisomal located enzymes, whereas in saccharomyces cerevisiae three separate genes specify compartment specific enzymes. we have identified a single gene, idpa, in the filamentous fungus aspergillus nidulans that specifies a protein with a high degree of identity to mammalian and ... | 2001 | 11483612 |
| the nsdd gene encodes a putative gata-type transcription factor necessary for sexual development of aspergillus nidulans. | the ability to reproduce both sexually and asexually is one of the characteristics of the homothalic ascomycete aspergillus nidulans. unlike the other aspergillus species, a. nidulans undergoes sexual development that seems to be regulated by internal and external stimuli. to begin to understand the sexual reproduction of a. nidulans we previously isolated and characterized several nsd (never in sexual development) mutants that failed to produce any sexual reproductive organs, and identified fou ... | 2001 | 11489119 |
| the lis1-related protein nudf of aspergillus nidulans and its interaction partner nude bind directly to specific subunits of dynein and dynactin and to alpha- and gamma-tubulin. | the nudf protein of aspergillus nidulans, which is required for nuclear migration through the fungal mycelium, closely resembles the lis1 protein required for migration of neurons to the cerebral cortex in humans. genetic experiments suggested that nudf influences nuclear migration by affecting cytoplasmic dynein. nudf interacts with another protein, nude, which also affects nuclear migration in a. nidulans. interactions among lis1, nude, dynein, and gamma-tubulin have been demonstrated in anima ... | 2001 | 11509576 |
| cell cycle progression and cell polarity require sphingolipid biosynthesis in aspergillus nidulans. | sphingolipids are major components of the plasma membrane of eukaryotic cells and were once thought of merely as structural components of the membrane. we have investigated effects of inhibiting sphingolipid biosynthesis, both in germinating spores and growing hyphae of aspergillus nidulans. in germinating spores, genetic or pharmacological inactivation of inositol phosphorylceramide (ipc) synthase arrests the cell cycle in g(1) and also prevents polarized growth during spore germination. howeve ... | 2001 | 11509663 |
| visualization of nuclei in aspergillus oryzae with egfp and analysis of the number of nuclei in each conidium by facs. | aspergillus oryzae has been reported to form conidia with multinuclei. in order to analyze nuclei in living cells, we developed an expression system of the a. nidutans histone h2b protein tagged by egfp (h2b::egfp). in both a. oryzae niad300 and a. nidulans fgsc89 transformants expressing h2b::egfp, fluorescence was detected in nuclear regions of hyphae and conidia. while a conidium contained only one fluorescent spot in the a. nidulans transformant, approximately 66% of conidia had two, 24% had ... | 2001 | 11515532 |
| in vivo and in vitro analyses of the amyr binding site of the aspergillus nidulans agda promoter; requirement of the cgg direct repeat for induction and high affinity binding of amyr. | the alpha-glucosidase gene (agda) of aspergillus nidulans has a single cggn8cgg type amyr binding site in its promoter region. the binding site is functional in vivo as a cis-element responsible for induction by starch, and mutational studies indicated that both the cgg triplets are required for high-level induction. a part of amyr (residues 1-411; amyr(1-411)), which was produced as a male fusion protein in e. coli, bound to the cggn8cgg site of the agda promoter. dna binding profiles to the mu ... | 2001 | 11515540 |
| a family of dna repeats in aspergillus nidulans has assimilated degenerated retrotransposons. | in the course of a chromosomal walk towards the centromere of chromosome iv of aspergillus nidulans, several cross-hybridizing genomic cosmid clones were isolated. restriction mapping of two such clones revealed that their restriction patterns were similar in a region of at least 15 kb, indicating the presence of a large repeat. the nature of the repeat was further investigated by sequencing and southern analysis. the study revealed a family of long dispersed repeats with a high degree of sequen ... | 2001 | 11523805 |
| induction of jlba mrna synthesis for a putative bzip protein of aspergillus nidulans by amino acid starvation. | the jlba (jun-like hzip) gene of aspergillus nidulans was isolated. the deduced amino acid motif of the c-terminal region of jlha encodes a putative dna-binding site composed of a basic amino acid domain and an adjacent leucine zipper motif. this region shares highest similarities to the c-terminal dna-binding domain and the basic zipper (bzip)-motifs of transcription factors like cpca from a. niger, gcn4p from saccharomyces cerevisiae, human junb and c-jun. the putative jlba protein contains a ... | 2001 | 11525406 |
| colorimetric assay for antifungal susceptibility testing of aspergillus species. | a colorimetric assay for antifungal susceptibility testing of aspergillus species (aspergillus fumigatus, aspergillus flavus, aspergillus terreus, aspergillus nidulans, and aspergillus ustus) is described based on the reduction of the tetrazolium salt 2,3-bis(2-methoxy-4-nitro-5-[(sulphenylamino)carbonyl]-2h-tetrazolium-hydroxide (xtt) in the presence of menadione as an electron-coupling agent. the combination of 200 microg of xtt/ml with 25 microm menadione resulted in a high production of form ... | 2001 | 11526191 |
| the structure and domain organization of escherichia coli isocitrate lyase. | enzymes of the glyoxylate-bypass pathway are potential targets for the control of many human diseases caused by such pathogens as mycobacteria and leishmania. isocitrate lyase catalyses the first committed step in this pathway and the structure of this tetrameric enzyme from escherichia coli has been determined at 2.1 a resolution. e. coli isocitrate lyase, like the enzyme from other prokaryotes, is located in the cytoplasm, whereas in plants, protozoa, algae and fungi this enzyme is found local ... | 2001 | 11526312 |
| reduced function of a phenylacetate-oxidizing cytochrome p450 caused strong genetic improvement in early phylogeny of penicillin-producing strains. | the single-copy paha gene from penicillium chrysogenum encodes a phenylacetate 2-hydroxylase that catalyzes the first step of phenylacetate catabolism, an oxidative route that decreases the precursor availability for penicillin g biosynthesis. paha protein is homologous to cytochrome p450 monooxygenases involved in the detoxification of xenobiotic compounds, with 84% identity to the aspergillus nidulans homologue phaca. expression level of paha displays an inverse correlation with the penicillin ... | 2001 | 11544206 |
| a new class of glutaminase from aspergillus oryzae. | the koji mold aspergillus oryzae is able to produce glutaminase which converts glutamine to glutamic acid, one of the most important flavor components in soy sauce. we present here the isolation and the complete nucleotide sequence of the glutaminase- encoding gene from a. oryzae u212, an industrial strain used in thailand. n-terminal and internal amino acid sequences were determined from purified glutaminase. a 700-bp fragment was amplified by pcr using oligonucleotide primers designed from par ... | 2001 | 11545278 |
| ethanol catabolism in aspergillus nidulans: a model system for studying gene regulation. | this article reviews our knowledge of the ethanol utilization pathway (alc system) in the hyphal fungus aspergillus nidulans. we discuss the progress made over the past decade in elucidating the two regulatory circuits controlling ethanol catabolism at the level of transcription, specific induction, and carbon catabolite repression, and show how their interplay modulates the utilization of nutrient carbon sources. the mechanisms featuring in this regulation are presented and their modes of actio ... | 2001 | 11550794 |
| transcriptional autoregulation and inhibition of mrna translation of amino acid regulator gene cpca of filamentous fungus aspergillus nidulans. | the cpca protein of the filamentous fungus aspergillus nidulans is a member of the c-jun-like transcriptional activator family. it acts as central transcription factor of the cross-pathway regulatory network of amino acid biosynthesis and is functionally exchangeable for the general control transcriptional activator gcn4p of saccharomyces cerevisiae. in contrast to gcn4, expression of cpca is strongly regulated by two equally important mechanisms with additive effects that lead to a fivefold inc ... | 2001 | 11553722 |
| srea is involved in regulation of siderophore biosynthesis, utilization and uptake in aspergillus nidulans. | under conditions of low iron availability, most fungi excrete siderophores in order to mobilize extracellular iron. we show that lack of the gata-type transcription factor srea in aspergillus nidulans not only leads to derepression of siderophore biosynthesis but also to deregulation of siderophore-bound iron uptake and ornithine esterase expression. furthermore, srea deficiency causes increased accumulation of ferricrocin, the siderophore responsible for intracellular iron storage. in srea dele ... | 2001 | 11555288 |
| molecular cloning of kpca gene encoding a kex2p-like endoprotease from aspergillus nidulans. | we cloned and sequenced a gene, kpca (kex2p-like proprotein convertase a), from a genomic library of aspergillus nidulans. the kpca gene encodes an 820-residue protein, named kpca, which contains a putative subtilisin-like catalytic domain (residues 136-466) homologous to that of the subtilisin serine protease family. kpca shows 56, 73, and 47% amino acid identities with saccharomyces cerevisiae kex2p, aspergillus niger kexb, and mouse furin within the subtilisin-like catalytic domain, respectiv ... | 2001 | 11561725 |
| the solution structure of an alcr-dna complex sheds light onto the unique tight and monomeric dna binding of a zn(2)cys(6) protein. | in aspergillus nidulans, the transcription activator alcr mediates specific induction of a number of the genes of the alc cluster. this cluster includes genes involved in the oxidation of ethanol and other alcohols to acetate. the pattern of binding and of transactivation of alcr is unique within the zn(2)cys(6) family. the structural bases for these specificities have not been analyzed at the atomic level until now. | 2001 | 11566132 |
| role of glutamine synthetase in nitrogen metabolite repression in aspergillus nidulans. | glutamine synthetase (gs), ec 6.3.1.2, is a central enzyme in the assimilation of nitrogen and the biosynthesis of glutamine. we have isolated the aspergillus nidulans glna gene encoding gs and have shown that glna encodes a highly expressed but not highly regulated mrna. inactivation of glna results in an absolute glutamine requirement, indicating that gs is responsible for the synthesis of this essential amino acid. even when supplemented with high levels of glutamine, strains lacking a functi ... | 2001 | 11566979 |
| role of ntcb in activation of nitrate assimilation genes in the cyanobacterium synechocystis sp. strain pcc 6803. | in synechocystis sp. strain pcc 6803, the genes encoding the proteins involved in nitrate assimilation are organized into two transcription units, nrtabcd-narb and nira, the expression of which was repressed by ammonium and induced by inhibition of ammonium assimilation, suggesting involvement of ntca in the transcriptional regulation. under inducing conditions, expression of the two transcription units was enhanced by nitrite, suggesting regulation by ntcb, the nitrite-responsive transcriptiona ... | 2001 | 11566981 |
| a fungal perspective on human inborn errors of metabolism: alkaptonuria and beyond. | crucial for the establishment and development of biochemical genetics as a self-standing discipline was beadle and tatum's choice of neurospora crassa as experimental organism some 60 years ago. although garrod's insights on biochemical genetics and his astonishingly modern concepts of biochemical individuality and susceptibility to disease had been ignored by their contemporaries, beadle acknowledged on several occasions how close garrod had come to the "one-gene-one-enzyme" hypothesis. in an u ... | 2001 | 11567547 |
| isolation of uv-induced mutations in the area nitrogen regulatory gene of aspergillus niger, and construction of a disruption mutant. | the area gene of filamentous fungi encodes a positive-acting transcriptional factor required for the expression of genes involved in the utilisation of nitrogen sources other than ammonium and glutamine. in aspergillus niger we have isolated three uv-induced area mutants and constructed a well-defined disruption allele of the area gene. the area gene was genetically localised on linkage group iii, 3.6 map units (m.u.) from bioa1 and 4.5 m.u. from lysa7. analysis of the expression of the nitrate ... | 2001 | 11589576 |
| cytochrome c is not essential for viability of the fungus aspergillus nidulans. | the filamentous fungus aspergillus nidulans is an obligate aerobe, which is capable of anaerobic survival, but not anaerobic growth. since cytochrome c forms an essential part of the oxidative respiratory pathway it was expected that mutants lacking this component would be non-viable. gene replacement of one homologue of the cyca (cytochrome c) gene was carried out in a diploid strain. benomyl-induced haploidisation of this diploid yielded all cyca+ haploid colonies, initially suggesting that lo ... | 2001 | 11589577 |
| the hypocrea jecorina hap 2/3/5 protein complex binds to the inverted ccaat-box (attgg) within the cbh2 (cellobiohydrolase ii-gene) activating element. | the 5' regulatory region of the chh2 gene, encoding cellobiohydrolase ii, of the filamentous fungus hypocrea jecorina contains the cbh2 activating element (cae) which is essential for cbh2 expression. the cae consists of two separate, adjacent motifs, a ccaat box on the template strand (attgg) and a gtaata box on the coding strand, which co-operate in the induction of the gene by cellulose or sophorose. emsa supershift experiments using an antibody against aspergillus nidulans hapc suggested tha ... | 2001 | 11589578 |
| gamma-tubulin and the c-terminal motor domain kinesin-like protein, klpa, function in the establishment of spindle bipolarity in aspergillus nidulans. | previous research has found that a gamma-tubulin mutation in schizosaccharomyces pombe is synthetically lethal with a deletion of the c-terminal motor domain kinesin-like protein gene pkl1, but the lethality of the double mutant prevents a phenotypic analysis of the synthetic interaction. we have investigated interactions between klpa1, a deletion of an aspergillus nidulans homolog of pkl1, and mutations in the mipa, gamma-tubulin gene. we find that klpa1 dramatically increases the cold sensitiv ... | 2001 | 11598200 |
| stable transformation of pleurotus ostreatus to hygromycin b resistance using lentinus edodes gpd expression signals. | it was reported that pleurotus ostreatus was transformed unstably using recombinant plasmids containing a hygromycin b phosphotransferase gene (hph) under the control of aspergillus nidulans expression signals, and that the plasmids were maintained extrachromosomally in the transformants. here we report a stable and integrative transformation of the fungus to hygromycin b resistance, using a recombinant hph fused with lentinus edodes glyceraldehyde-3-phosphate dehydrogenase expression signals. r ... | 2001 | 11601618 |
| the aspergillus nidulans snt genes are required for the regulation of septum formation and cell cycle checkpoints. | in aspergillus nidulans, germinating conidia undergo multiple rounds of nuclear division before forming a septum. previous genetic results suggest that the ability to separate nuclear division and septum formation depends upon a threshold level of activity of the cyclin-dependent kinase nimx(cdk1). mutations in nimx and nimt, the gene encoding the nimx(cdk1)-activating phosphatase, have revealed that tyr-15 phosphorylation is important for determining the timing of the formation of the first sep ... | 2001 | 11606533 |
| an inhibitor-resistant histone deacetylase in the plant pathogenic fungus cochliobolus carbonum. | we have partially purified and characterized histone deacetylases of the plant pathogenic fungus cochliobolus carbonum. depending on growth conditions, this fungus produces hc-toxin, a specific histone deacetylase inhibitor. purified enzymes were analyzed by immunoblotting, by immunoprecipitation, and for toxin sensitivity. the results demonstrate the existence of at least two distinct histone deacetylase activities. a high molecular weight complex (430,000) is sensitive to hc-toxin and trichost ... | 2001 | 11669622 |
| seph, a cdc7p orthologue from aspergillus nidulans, functions upstream of actin ring formation during cytokinesis. | in the filamentous fungus, aspergillus nidulans, multiple rounds of nuclear division occur before cytokinesis, allowing an unambiguous identification of genes required specifically for cytokinesis. as in animal cells, both an intact microtubule cytoskeleton and progression through mitosis are required for actin ring formation and contraction. the seph gene from a. nidulans was discovered in a screen for temperature-sensitive cytokinesis mutants. sequence analysis showed that seph is 42% identica ... | 2001 | 11679062 |
| genetic evidence for a microtubule-destabilizing effect of conventional kinesin and analysis of its consequences for the control of nuclear distribution in aspergillus nidulans. | conventional kinesin is a microtubule-dependent motor protein believed to be involved in a variety of intracellular transport processes. in filamentous fungi, conventional kinesin has been implicated in different processes, such as vesicle migration, polarized growth, nuclear distribution, mitochondrial movement and vacuole formation. to gain further insights into the functions of this kinesin motor, we identified and characterized the conventional kinesin gene, kina, of the established model or ... | 2001 | 11679072 |
| mutation of luxs affects growth and virulence factor expression in streptococcus pyogenes. | adaptive responses of bacteria that involve sensing the presence of other bacteria are often critical for proliferation and the expression of virulence characteristics. the autoinducer ii (ai-2) pathway has recently been shown to be a mechanism for sensing other bacteria that is highly conserved among diverse bacterial species, including gram-positive pathogens. however, a role for this pathway in the regulation of virulence factors in gram-positive pathogens has yet to be established. in this s ... | 2001 | 11679074 |
| characterization of nitrogen metabolite signalling in aspergillus via the regulated degradation of area mrna. | area is the principal transcription factor involved in determining nitrogen utilization in aspergillus nidulans. nh4+ and gln are utilized preferentially but in their absence, area acts to facilitate the expression of genes involved in metabolizing alternative nitrogen sources. it is crucial to the function of area that its expression is tightly modulated by the quality and availability of nitrogen sources. one signalling mechanism involves regulated degradation of the area transcript in respons ... | 2001 | 11679084 |
| expression, purification and crystallization of aspergillus nidulans nmra, a negative regulatory protein involved in nitrogen-metabolite repression. | the nmra repressor protein of aspergillus nidulans was overproduced in escherichia coli and purified to homogeneity. gel-exclusion chromatography showed that nmra was monomeric in solution under the buffer conditions used. the protein was crystallized in three forms, belonging to trigonal, monoclinic and hexagonal space groups. two of these crystal forms (a and b) diffract to high resolution and thus appear suitable for structure determination. crystal form a belongs to space group p3((1))21, wi ... | 2001 | 11679757 |
| transcriptional regulation of the nitrate reductase gene in chlorella vulgaris: identification of regulatory elements controlling expression. | nitrate reductase (nr), the rate-limiting and primary control point of the nitrate assimilation pathway, is regulated at transcriptional and post-transcriptional levels. to better understand how nr is regulated at the transcriptional level in chlorella vulgaris, studies were performed to identify the factors regulating nr expression. sequence analysis of the nr promoter identified a number of potential sites that were investigated by mobility shift assays. of the protein-binding sites found, sev ... | 2001 | 11680822 |