Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| the aspergillus nidulans ccaat-binding factor ancp/ancf is a heteromeric protein analogous to the hap complex of saccharomyces cerevisiae. | the aspergillus nidulans hapc gene was expressed as a fusion protein with male or glutathione-s-transferase (gst) in escherichia coli, and used for the purification of hapc and the preparation of anti-hapc antiserum. the ccaat-binding factor ancp/ancf contains a component with an approximate molecular mass of 32 kda that cross-reacts with the antibody. the male-hapc fusion protein was able to replace authentic hapc in ancp when incubated under appropriate conditions. furthermore, reconstitution ... | 1998 | 9529521 |
| electrotransformation and expression of bacterial genes encoding hygromycin phosphotransferase and beta-galactosidase in the pathogenic fungus histoplasma capsulatum. | we developed an efficient electrotransformation system for the pathogenic fungus histoplasma capsulatum and used it to examine the effects of features of the transforming dna on transformation efficiency and fate of the transforming dna and to demonstrate fungal expression of two recombinant escherichia coli genes, hph and lacz. linearized dna and plasmids containing histoplasma telomeric sequences showed the greatest transformation efficiencies, while the plasmid vector had no significant effec ... | 1998 | 9529100 |
| facb, the aspergillus nidulans activator of acetate utilization genes, binds dissimilar dna sequences. | the facb gene is required for acetate induction of acetamidase (amds) and the acetate utilization enzymes acetyl-coa synthase (faca), isocitrate lyase (acud) and malate synthase (acue) in aspergillus nidulans. the facb gene encodes a transcriptional activator with a gal4-type zn(ii)2cys6 zinc binuclear cluster dna-binding domain which is shown to be required for dna binding. in vitro dna-binding sites for facb in the 5' regions of the amds, faca, acud and acue genes have been identified. mutatio ... | 1998 | 9524126 |
| the role of the dynactin complex in intracellular motility. | dynactin is a multisubunit complex that binds to the minus-end-directed microtubule motor cytoplasmic dynein and may provide a link between the motor and its cargo. results from genetic studies in saccharomyces cerevisiae, neurospora crassa, aspergillus nidulans, and drosophila have suggested that cytoplasmic dynein and dynactin function in the same cellular pathways. p150glued, a vertebrate homologue of the drosophila gene glued, is the largest polypeptide in the dynactin complex with multiple ... | 1998 | 9522459 |
| the aspergillus nidulans sulphur regulatory gene sconb encodes a protein with wd40 repeats and an f-box. | the aspergillus nidulans gene sconb, one of the four identified genes controlling sulphur metabolite repression, was cloned and analysed. it encodes a polypeptide of 678 amino acids containing seven wd repeats characteristic of the large wd40 family of eukaryotic regulatory proteins. the sconb protein has nuclear localisation signals and is very similar to the neurospora crassa scon2 and saccharomyces cerevisiae met30 proteins, both of which are involved in the regulation of sulphur metabolism. ... | 1998 | 9520259 |
| mapping of the nitrate-assimilation gene cluster (crna-niia-niad) and characterization of the nitrite reductase gene (niia) in the opportunistic fungal pathogen aspergillus fumigatus. | this study reports the molecular characterization of the nitrate-assimilation gene cluster from the opportunistic fungal pathogen aspergillus fumigatus. a genomic fragment was isolated which contained the entire structural gene encoding nitrite reductase (niia), plus segments of the nitrate reductase (niad) and the nitrate transporter (crna) genes. nitrate-assimilation genes in a. fumigatus are physically linked and transcribed in the same direction as in a. nidulans. the nitrate-assimilation ge ... | 1998 | 9508795 |
| genetic analysis of resistance to fenpropimorph in aspergillus niger. | resistance to the morpholine-fungicide fenpropimorph was studied in aspergillus niger and a. nidulans. mass selection of conidia of a. nidulans on agar amended with the fungicide at different concentrations did not yield of resistant mutants, even after uv-treatment of the conidia. in contrast, similar experiments with a. niger generated many fenpropimorph-resistant mutants. the mutants displayed cross-resistance to fenpropidin and generally showed wild-type sensitivity to the unrelated toxicant ... | 1998 | 9506903 |
| structure and regulation of cysd, the homocysteine synthase gene of aspergillus nidulans. | the a. nidulans cysd gene encoding homocysteine synthase (o-acetyl-l-homoserine sulphydrylase) has been isolated by functional complementation of a cysd11 mutation. the gene contains five short introns and codes for a protein of 437 amino acids. the protein shows homology with bacterial and yeast o-acetyl- and o-succinyl-homoserine sulphydrylases, particularly from schizosaccharomyces pombe, saccharomyces cerevisiae and kluyveromyces lactis. the cysd cdna is able to complement a s. cerevisiae mu ... | 1998 | 9506902 |
| hyp loci control cell pattern formation in the vegetative mycelium of aspergillus nidulans. | aspergillus nidulans grows by apical extension of multinucleate cells called hyphae that are subdivided by the insertion of crosswalls called septa. apical cells vary in length and number of nuclei, whereas subapical cells are typically 40 microm long with three to four nuclei. apical cells have active mitotic cycles, whereas subapical cells are arrested for growth and mitosis until branch formation reinitiates tip growth and nuclear divisions. this multicellular growth pattern requires coordina ... | 1998 | 9504915 |
| cloning and characterization of a chitinase-encoding gene (chia) from aspergillus nidulans, disruption of which decreases germination frequency and hyphal growth. | we cloned a chitinase-encoding gene from aspergillus nidulans by polymerase chain reaction using degenerated oligonucleotide primers designed from the conserved amino acid sequences among chitinases from yeasts and rhizopus spp. the cloned gene, named chia, encoded a polypeptide consisting of 660 amino acids. disruption of chia had no effect on hyphal or conidiophore morphology, but germination frequency and hyphal growth rate decreased substantially. expression of chia was investigated using es ... | 1998 | 9501518 |
| regulation of the aspergillus nidulans penicillin biosynthesis gene acva (pcbab) by amino acids: implication for involvement of transcription factor pacc. | the beta-lactam antibiotic penicillin is produced as an end product by some filamentous fungi only. it is synthesized from the amino acid precursors l-alpha-aminoadipic acid, l-cysteine, and l-valine. previous data suggested that certain amino acids play a role in the regulation of its biosynthesis. therefore, in this study the effects of externally added amino acids on both aspergillus (emericella) nidulans penicillin production and expression of the bidirectionally oriented biosynthesis genes ... | 1998 | 9501424 |
| the crea repressor is the sole dna-binding protein responsible for carbon catabolite repression of the alca gene in aspergillus nidulans via its binding to a couple of specific sites. | carbon catabolite repression is mediated in aspergillus nidulans by the negative acting protein crea. the crea repressor plays a major role in the control of the expression of the alc regulon, encoding proteins required for the ethanol utilization pathway. it represses directly, at the transcriptional level, the specific transacting gene alcr, the two structural genes alca and alda, and other alc genes in all physiological growth conditions. among the seven putative crea sites identified in the ... | 1998 | 9497366 |
| opposite patterns of expression of two aspergillus nidulans xylanase genes with respect to ambient ph. | the aspergillus nidulans xylanase genes xlna and xlnb are subject to regulation by ambient ph via the zinc finger transcription factor pacc. in the presence of d-xylose, xlna is expressed under conditions of alkaline ambient ph while xlnb is expressed at acidic ambient ph. these data have been confirmed for acidity- and alkalinity-mimicking a. nidulans mutants. | 1998 | 9495775 |
| quantitative immuno-slot blot assay to measure acmpk protein in cell extracts of aspergillus nidulans. | 1998 | 9494720 | |
| the recombinant antigen aspnd1r from aspergillus nidulans is specifically recognized by sera from patients with aspergilloma. | a 996 bp aspergillus nidulans cdna encoding the aspnd1 immunodominant antigen was cloned and expressed in escherichia coli as a fusion protein with the enzyme glutathione s-transferase (gst) from schistosoma japonicum. the gst-aspnd1 fusion protein was purified from isolated bacterial inclusion bodies by preparative sds-page. after cleavage with thrombin, the aspnd1 recombinant antigen (aspnd1r) and the gst protein were separated by sds-page and immunoblotted with a number of different human ser ... | 1998 | 9493392 |
| purification and characterization of the nuclear ribonuclease p of aspergillus nidulans. | in aspergillus nidulans, the nuclear ribonuclease p was separated from its mitochondrial counterpart by q-sepharose chromatography, and a precursor-trna(his) processing assay system was used to discriminate nuclear ribonuclease p activity from the mitochondrial counterpart. the nuclear ribonuclease p was purified to near homogeneity from whole-cell extracts. a 2150-fold purification with a yield of 2.3% was achieved by five types of chromatography including trna affinity chromatography and glyce ... | 1998 | 9492290 |
| a nima homologue promotes chromatin condensation in fission yeast. | entry into mitosis requires p34(cdc2), which activates downstream mitotic events through phosphorylation of key target proteins. in aspergillus nidulans, the nima protein kinase has been identified as a potential downstream target and plays a role in regulating chromatin condensation at mitosis. nima- mutants arrest in a state that physically resembles interphase even though p34(cdc2) is fully active. despite evidence for the existence of nima-like activities in a variety of cell types, the only ... | 1998 | 9490640 |
| mutations in the bimc box of cut7 indicate divergence of regulation within the bimc family of kinesin related proteins. | members of the bimc family of kinesin related proteins (krps) play vital roles in the formation and function of the mitotic spindle. although they share little amino acid homology outside the highly conserved microtubule motor domain, several family members do contain a 'bimc box', a sequence motif around a p34(cdc2) consensus phosphorylation site in their carboxy-terminal 'tail' region. one family member, eg5, requires phosphorylation at this site for association with the mitotic spindle. we sh ... | 1998 | 9490630 |
| the penicillin regulator penr1 of aspergillus nidulans is a hap-like transcriptional complex. | in aspergillus nidulans, a dna-binding complex, penr1, was shown to bind to two ccaat-box-containing dna elements located in the promoter regions of the bidirectionally oriented penicillin biosynthesis genes acva and ipna, and of the aat promoter. here, partial purification of penr1 and western blotting using anti-hapc sera indicated that the previously identified hapc protein, which was suggested to be part of the ccaat-binding complex ancf, is also part of penr1. this was confirmed by band shi ... | 1998 | 9490049 |
| the regulator of nitrate assimilation in ascomycetes is a dimer which binds a nonrepeated, asymmetrical sequence. | the regulation of nitrate assimilation seems to follow the same pattern in all ascomycetes where this process has been studied. we show here by in vitro binding studies and a number of protection and interference techniques that the transcription factor mediating nitrate induction in aspergillus nidulans, a protein containing a binuclear zinc cluster dna binding domain, recognizes an asymmetrical sequence of the form ctcc ghgg. we further show that the protein binds to its consensus site as a di ... | 1998 | 9488449 |
| an ethanol inducible gene switch for plants used to manipulate carbon metabolism. | many transgenic plant studies use constitutive promoters to express transgenes. for certain genes, deleterious effects arise from constant expression in all tissues throughout development. we describe a chemically inducible plant gene expression system, with negligible background activity, that obviates this problem. we demonstrate its potential by showing inducible manipulation of carbon metabolism in transgenic plants. upon rapid induction of yeast cytosolic invertase, a marked phenotype appea ... | 1998 | 9487526 |
| an intoxicating switch for plant transgene expression. | 1998 | 9487515 | |
| conservation of the active site motif in aspergillus niger (ficuum) ph 6.0 optimum acid phosphatase and kidney bean purple acid phosphatase. | aspergillus niger (ficuum) and the kidney bean purple acid phosphatases retained all the essential amino acids in the active site despite a low degree of total sequence homology. this high degree of homology in the sequence motif of a. niger fungal acid phosphatase (apase6) active site with kidney bean metallo phosphoesterase (kbpap) and the absence of the rhg-xrxp sequence motif indicates apase6 to be a metallophosphoesterase rather than a histidine acid phosphatase. | 1998 | 9480832 |
| isolation and characterisation of cycloheximide-sensitive mutants of aspergillus nidulans. | aspergillus nidulans is a non-pathogenic fungus with well-developed genetics which provides an excellent model system for studying different aspects of drug resistance in filamentous fungi. as a preliminary step to characterizing genes that confer pleiotropic drug resistance in aspergillus, we isolated cycloheximide-sensitive mutants of a. nidulans, which is normally resistant to this drug. the rationale for this approach is to identify genes whose products are important for drug resistance by a ... | 1998 | 9472081 |
| emericella nidulans as an agent of guttural pouch mycosis in a horse. | a case is reported in a 9-year-old anglo-arab horse with guttural pouch mycosis caused by emericella nidulans. acute death occurred by exsanguination following erosion of the external carotid artery. histopathological examination of the mycotic plaque demonstrated septate hyphae, conidial heads, hülle cells and mature cleistothecia containing characteristic ascospores. specific identification was confirmed by culture. in accordance with previous reports, emericella nidulans should be considered ... | 1997 | 9467112 |
| plant-adapted green fluorescent protein is a versatile vital reporter for gene expression, protein localization and mitosis in the filamentous fungus, aspergillus nidulans. | green fluorescent protein (gfp) is a useful reporter to follow the in vivo behaviour of proteins, but the wild-type gfp gene does not function in many organisms, including many plants and filamentous fungi. we show that codon-modified forms of gfp, produced for use in plants, function effectively in aspergillus nidulans both as gene expression reporters and as vital reporters for protein location. to demonstrate the use of these modified gfps as reporter genes we have used fluorescence to follow ... | 1998 | 9466261 |
| identification of new regulatory genes controlling synthesis of folate-dependent enzymes in aspergillus nidulans. | prototrophic revertants of a meth2 strain of aspergillus nidulans which is impaired in the regulation of synthesis of folate-dependent enzymes were isolated and six of them analysed. in three of the isolates reversion was the result of an intragenic suppressor mutation in the meth locus. in the remaining strains suppressor mutations occurred in independent genes. these genes, designated fola, folb and folc, are linked and located in chromosome vi. mutations in these genes render synthesis of som ... | 1997 | 9462964 |
| detection of aspergillus ribosomal rna using biotinylated oligonucleotide probes. | aspergillosis continues to be a devastating disease entity that results in significant mortality in immunosuppressed patients. rapid diagnosis is often required to initiate appropriate therapy. although the histopathologist may be able to visualize fungal organisms in tissue specimens, the histology of aspergillus species may overlap with a variety of fungi, so diagnosis often relies on fungal cultures that can take weeks to complete. recently, an in situ hybridization assay targeting aspergillu ... | 1997 | 9458383 |
| expression of rnudc, a potential nuclear movement protein, in mammalian cells: localization to the golgi apparatus. | prolactin and other cytokines regulate lymphocyte proliferation through the activation of a number of genes, one of which was identified as rnudc from a prolactin-dependent rat t cell line, nb2. rnudc encodes a 45-kda protein whose carboxy terminal 94 amino acids are similar to the carboxy terminus of the aspergillus nidulans nuclear movement protein nudc. in nb2 t cells, rnudc protein levels are induced two- to threefold by prolactin stimulation. this prolactin-inducible increase in rnudc prote ... | 1998 | 9457053 |
| umchs5, a gene coding for a class iv chitin synthase in ustilago maydis. | a fragment corresponding to a conserved region of a fifth gene coding for chitin synthase in the plant pathogenic fungus ustilago maydis was amplified by means of the polymerase chain reaction (pcr). the amplified fragment was utilized as a probe for the identification of the whole gene in a genomic library of the fungus. the predicted gene product of umchs5 has highest similarity with class iv chitin synthases encoded by the chs3 genes from saccharomyces cerevisiae and candida albicans, chs-4 f ... | 1997 | 9454647 |
| microbial models of soil metabolism: biotransformations of danofloxacin. | danofloxacin is a new synthetic fluoroquinolone antibacterial agent under development for exclusive use in veterinary medicine. such use could lead to deposition of low levels of danofloxacin residues in the environment in manure from treated livestock. this study was conducted to evaluate the potential for indigenous soil microorganisms to metabolize danofloxacin. cultures of 72 soil microorganisms representing a diverse panel of bacteria, fungi and yeast were incubated with danofloxacin mesyla ... | 1997 | 9451835 |
| identification and analysis of a class 2 alpha-mannosidase from aspergillus nidulans. | a class 2 alpha-mannosidase gene was cloned and sequenced from the filamentous fungus aspergillus nidulans. a portion of the gene was amplified using degenerate oligonucleotide primers which were designed based on similarity between the saccharomyces cerevisiae vacuolar and rat er/cytosolic class 2 protein sequences. the pcr amplification product was used to isolate the full length gene, and dna sequencing revealed a 3383 bp coding region containing three introns. the predicted 1049 amino acid r ... | 1998 | 9451011 |
| atp: citrate lyase from aspergillus nidulans. | 1997 | 9450098 | |
| malic enzyme: a lipogenic enzyme in fungi. | 1997 | 9450097 | |
| dehydroquinate synthase binds divalent and trivalent cations: role of metal binding in catalysis. | 1997 | 9450037 | |
| direct sulfhydrylation for methionine biosynthesis in leptospira meyeri. | a gene library of the leptospira meyeri serovar semaranga strain veldrat s.173 dna has been constructed in a mobilizable cosmid with inserts of up to 40 kb. it was demonstrated that a leptospira dna fragment carrying mety complemented escherichia coli strains carrying mutations in metb. the latter gene encodes cystathionine gamma-synthase, an enzyme which catalyzes the second step of the methionine biosynthetic pathway. the mety gene is 1,304 bp long and encodes a 443-amino-acid protein with a m ... | 1998 | 9440513 |
| the myosin i sh3 domain and teds rule phosphorylation site are required for in vivo function. | the class i myosins play important roles in controlling many different types of actin-based cell movements. dictyostelium cells either lacking or overexpressing amoeboid myosin is have significant defects in cortical activities such as pseudopod extension, cell migration, and macropinocytosis. the existence of dictyostelium null mutants with strong phenotypic defects permits complementation analysis as a means of exploring important functional features of the myosin i heavy chain. mutant dictyos ... | 1998 | 9436992 |
| the in vivo expression pattern of mouse nek2, a nima-related kinase, indicates a role in both mitosis and meiosis. | the human protein kinase nek2 is related to the nima cell cycle regulatory kinase of aspergillus nidulans. whereas nima has been shown to be essential for cell cycle progression into mitosis in this fungus, the function of mammalian nek2 remains to be elucidated. in this study, we isolated a cdna coding for a mouse ortholog of human nek2 and analyzed the expression of this kinase in different organs. rnase protection assays performed on rnas from mouse adult organs showed very high expression of ... | 1997 | 9434622 |
| first experimental evidence of a zinc binuclear cluster in alcr protein, mutational and x-ray absorption studies. | alcr is the transcriptional activator of the ethanol utilization pathway in aspergillus nidulans. the zinc dna-binding domain contains ligands of zinc, six cysteines (zn2cys6) or five cysteines and one histidine (zn2cys5his). the utilisation of complementary approaches such as x-ray absorption spectroscopy, mutational analysis, zinc content evaluation, determination of specific binding connecting structural and biological data, have allowed to determine zinc environment and to analyse the involv ... | 1997 | 9434111 |
| a centrosomal function for the human nek2 protein kinase, a member of the nima family of cell cycle regulators. | nek2, a mammalian protein kinase of unknown function, is closely related to the mitotic regulator nima of aspergillus nidulans. here we show by both immunofluorescence microscopy and biochemical fractionation that human nek2 localizes to the centrosome. centrosome association occurs throughout the cell cycle, including all stages of mitosis, and is independent of microtubules. overexpression of active nek2 induces a striking splitting of centrosomes, whereas prolonged expression of either active ... | 1998 | 9430639 |
| integrity of a zn finger-like domain in samb is crucial for morphogenesis in ascomycetous fungi. | genetic features determine the site of polarized growth in filamentous fungi and lead to hyphal tip extension or subapical branching. we have isolated the samb gene (suppressor of anucleate metulae) of aspergillus nidulans which encodes a 66 kda protein carrying an atypical cys4 and an additional cys2/his/cys zn finger motif at the carboxy-terminus. such novel zn finger-like domains have recently been found in several other developmental regulators in organisms ranging from yeast to man. deletio ... | 1998 | 9427754 |
| cloning and characterization of the aspergillus nidulans dna topoisomerase i gene. | the topoisomerase i (top1) gene was cloned and sequenced from aspergillus nidulans using the polymerase chain reaction (pcr). genomic dna was used as a template to obtain a 2987-bp gene containing five small introns. pcr from a cdna library yielded a 2613-bp sequence which codes for an 871 amino acid protein. comparison of the deduced amino acid sequence with other dna topoisomerase i (topo i) protein sequences shows a somewhat higher degree of identity with other fungal amino acid sequences tha ... | 1997 | 9426247 |
| expression of the cefg gene is limiting for cephalosporin biosynthesis in acremonium chrysogenum. | the conversion of deacetylcephalosporin c to cephalosporin c is inefficient in most acremonium chrysogenum strains. the cefg gene, which encodes deacetylcephalosporin c acetyltransferase, is expressed very poorly in a. chrysogenum as compared to other genes of the cephalosporin pathway. introduction of additional copies of the cefg gene with its native promoter (in two different constructions with upstream regions of 1056 bp and 538 bp respectively) did not produce a significant increase of the ... | 1997 | 9421924 |
| specific dna recognition by the aspergillus nidulans three zinc finger transcription factor pacc. | the three zinc fingers of pacc, the transcription factor mediating ph regulation in aspergillus nidulans, are necessary and sufficient to recognise specifically the target ipna2 site. missing nucleoside footprints confirmed the core target (double-stranded) hexanucleotide 5'-gccaag-3'. any base substitution resulted in substantial or complete loss of binding, excepting a5 (partially replaceable by g). a t preceding the hexanucleotide enhanced binding. interference footprinting indicates that the ... | 1997 | 9417928 |
| characterization of a fungal maleylacetoacetate isomerase gene and identification of its human homologue. | we have previously used aspergillus nidulans as a fungal model for human phenylalanine catabolism. this model was crucial for our characterization of the human gene involved in alcaptonuria. we use here an identical approach to characterize at the cdna level the human gene for maleylacetoacetate isomerase (maai, ec 5.2.1.2), the only as yet unidentified structural gene of the phenylalanine catabolic pathway. we report here the first characterization of a gene encoding a maai enzyme from any orga ... | 1998 | 9417084 |
| relationship of actin, microtubules, and crosswall synthesis during septation in aspergillus nidulans. | studies of cytokinesis in animal cells demonstrate that microtubules play an important role in signaling the position of the actin-containing contractile ring and subsequent formation of the cleavage furrow. septation in several fungi closely resembles animal cell cytokinesis in that a circumferential ring of actin is visible at the incipient division site. however, this does not necessarily mean that division is contractile since actin may also serve to localize septal wall synthesis. in additi ... | 1997 | 9415379 |
| in vitro reconstruction of the aspergillus (= emericella) nidulans genome. | a physical map of the 31-megabase aspergillus nidulans genome is reported, in which 94% of 5,134 cosmids are assigned to 49 contiguous segments. the physical map is the result of a two-way ordering process, in which clones and probes were ordered simultaneously on a binary dna/dna hybridization matrix. compression by elimination of redundant clones resulted in a minimal map, which is a chromosome walk. repetitive dna is nonrandomly dispersed in the a. nidulans genome, reminiscent of heterochroma ... | 1997 | 9405653 |
| structure and physiological function of calpains. | for a long time now, two ubiquitously expressed mammalian calpain isoenzymes have been used to explore the structure and function of calpain. although these two calpains, mu- and m-calpains, still attract intensive interest because of their unique characteristics, various distinct homologues to the protease domain of mu- and m-calpains have been identified in a variety of organisms. some of these 'novel' calpain homologues are involved in important biological functions. for example, p94 (also ca ... | 1997 | 9396712 |
| g protein alpha subunit genes control growth, development, and pathogenicity of magnaporthe grisea. | three g protein alpha subunit genes have been cloned and characterized from magnaporthe grisea: maga is very similar to cpg-2 of cryphonectria parasitica; magb is virtually identical to cpg-1 of cryphonectria parasitica, to gna1 of neurospora crassa, and to fada of emericella nidulans; and magc is most similar to gna2 of neurospora crassa. homologous recombination resulting in targeted deletion of maga had no effect on vegetative growth, conidiation, or appressorium formation. deletion of magc r ... | 1997 | 9390422 |
| expression of wild-type and mutated drosophila melanogaster xanthine dehydrogenases in aspergillus nidulans. | 1997 | 9388736 | |
| cloning and characterisation of the adenosyl phosphosulphate kinase gene from aspergillus nidulans. | the sd gene of aspergillus nidulans has been cloned by heterologous screening of rationally selected cosmids. co-transformation of the sd50 mutant jmp1 confirmed the presence of a functional gene. sequence analysis determined this gene to be 680 bp in length, containing a 59-bp intron and encoding a protein of 206 amino acids. a protein-sequence comparison revealed a similarity to the c-terminal region of atp sulphurylase, the sc gene product. further sequence comparison revealed differences in ... | 1997 | 9388296 |
| self-splicing activity of the mitochondrial group-i introns from aspergillus nidulans and related introns from other species. | the mitochondrial genome of aspergillus nidulans contains several group-i introns. each one has been assayed for its ability to self-splice in vitro in the absence of proteins. the intron from the apocytochrome b gene is unusual among subgroup ib4 introns in being able to self-splice, unlike a similar intron from saccharomyces cerevisiae. the first intron in the cytochrome oxidase subunit-1 gene self-splices but only correctly completes the first step of splicing; cryptic 3' splice-sites are rec ... | 1997 | 9388295 |
| characterization of oleate-nonutilizing mutants of aspergillus nidulans isolated by the 3-amino-1,2,4-triazole positive selection method. | conidia of aspergillus nidulans were mutagenized with ultraviolet light and were incubated on a special selective medium containing the catalase inhibitor 3-amino-1,2,4-triazole. from approximately 5 x 10(7) viable uv-irradiated conidia tested, 423 stable mutants resistant to 3-amino-1,2,4-triazole were recovered, of which 40 were unable to grow on minimal medium with oleic acid as the sole carbon source. these oleate-nonutilizing (ole-) mutants did not grow on medium with carbon sources requiri ... | 1997 | 9385142 |
| a rapid method for chromatin structure analysis in the filamentous fungus aspergillus nidulans. | a rapid method for nuclease digestion of aspergillus nidulans chromatin is described. it overcomes the need for nuclear purification or protoplast preparation. the method is valid for the analysis of the nucleosomal repeat length in bulk chromatin, and allows the analysis of nucleosome phasing at a specific locus. | 1997 | 9380523 |
| nuclear traffic in fungal hyphae: in vivo study of nuclear migration and positioning in aspergillus nidulans. | nuclear migration and nuclear positioning are fundamental processes in all eukaryotic cells. they are easily monitored during hyphal growth of filamentous fungi. we expressed the green fluorescent protein (gfp) as a fusion protein with the putative nuclear localization domain of the transcriptional activator stua in nuclei of aspergillus nidulans and visualized these organelles in living cells. nuclear staining was observed in interphase nuclei but not during mitosis. nuclear division, nuclear m ... | 1997 | 9379904 |
| characterization of dnudc, the drosophila homolog of an aspergillus gene that functions in nuclear motility. | nuclear migration plays a prominent role in a broad range of developmental processes. we have cloned a drosophila gene, dnudc, encoding a protein that is evolutionarily conserved between humans and fungi. the aspergillus homolog, nudc, is one of a group of genes required for nuclear migration. dnudc encodes a 38.5-kda protein, and the carboxy terminal half of the protein shares 52% amino acid identity with aspergillus nudc. we show that the structural homology between dnudc and nudc extends to t ... | 1997 | 9376324 |
| a zinc finger protein required for stationary phase viability in fission yeast. | yeast cells exit the cell cycle and enter a metabolically inert stationary phase when starved for nutrients essential for normal proliferation. we have cloned a novel gene named rsv1+ (required for stationary phase viability) that is essential for fission yeast cell viability in a stationary phase induced by glucose starvation. rsv1+ encodes a 47 kda protein with two zinc finger motifs that are partially homologous with aspergillus nidulans crea, saccharomyces cerevisiae mig1 and mammalian egr-1 ... | 1997 | 9372444 |
| characterization of the mitochondrial cytochrome b gene from venturia inaequalis. | a new class of agricultural fungicides derived from the group of antifungal strobilurins acts as specific respiration inhibitors by binding to mitochondrial cytochrome b. the cytochrome b gene was cloned and sequenced from the mitochondrial genome of venturia inaequalis, the causal agent of apple scab. the gene was 10.65 kbp in size and contained seven exons and six introns. the exons encoded a protein of 393 amino acids. comparison of the deduced amino-acid sequence with cytochrome b proteins f ... | 1997 | 9371888 |
| 6-n-hydroxylaminopurine (hap)-induced accumulation of variability in haploid and diploid strains of aspergillus nidulans. | haploid and diploid strains of aspergillus nidulans have been repeatedly treated with the strong mutagen 6-n-hydroxylaminopurine (hap) which causes only base substitutions. an enormous amount of variability may be rapidly accumulated in haploid or diploid strains of a. nidulans. in particular, in the diploids the analysis of the results shows that after 12 cycles of treatment the conidia differ from each other for about ten recessive lethals and therefore probably for several hundreds of mutatio ... | 1997 | 9371884 |
| molecular characterization of mutants of the acetate regulatory gene facb of aspergillus nidulans. | the facb gene of aspergillus nidulans encodes a dna binding transcriptional activator required for growth on acetate as a sole carbon source. facb contains n-terminal gal4-like zn(ii)2cys6 (or c6 zinc) binuclear cluster dna binding and leucine zipper-like heptad repeat motifs and central and c-terminal acidic alpha-helical regions. facb recessive loss of function mutants are deficient in acetate induction of acetyl-coa synthase, isocitrate lyase, malate synthase, acetamidase, and nadp-isocitrate ... | 1997 | 9367656 |
| crystal structure of dna photolyase from anacystis nidulans. | the crystal structure at 1.8 a resolution of 8-hdf type photolyase from a. nidulans shows a backbone structure similar to that of mthf type e. coli photolyase but reveals a completely different binding site for the light-harvesting cofactor. | 1997 | 9360600 |
| the aspergillus nidulans cnxabc locus is a single gene encoding two catalytic domains required for synthesis of precursor z, an intermediate in molybdenum cofactor biosynthesis. | the aspergillus nidulans complex locus, cnxabc, has been shown to be required for the synthesis of precursor z, an intermediate in the molybdopterin cofactor pathway. the locus was isolated by chromosome walking a physical distance of 65-kilobase pairs from the brla gene and defines a single transcript that encodes, most likely, a difunctional protein with two catalytic domains, cnxa and cnxc. mutations (cnxa) affecting the cnxa domain, mutants (cnxc) in the cnxc domain, and frameshift (cnxb) mu ... | 1997 | 9353296 |
| deletion of the n-terminal region of the area protein is correlated with a derepressed phenotype with respect to nitrogen metabolite repression. | the entire area gene and a truncated version lacking the sequence encoding the n-terminal 389 amino acids were expressed from the qute promoter and terminator in an aspergillus nidulans strain with the endogenous area gene deleted. this expression system was used to decouple the effects of transcription regulation and mrna stability mediated by the native promoter and terminator from any posttranslational modulation of area activity. both the full-length area protein and the truncated form were ... | 1997 | 9352912 |
| cloning of the phytases from emericella nidulans and the thermophilic fungus talaromyces thermophilus. | phytases (ec 3.1.3.8) belong to the family of histidine acid phosphatases. we have cloned the phytases of the fungi emericella nidulans and talaromyces thermophilus. the putative enzyme encoded by the e. nidulans sequence consists of 463 amino acids and has a mr of 51785. the protein deduced from the t. thermophilus sequence consists of 466 amino acids corresponding to a mr of 51450. both predicted amino acid sequences exhibited high identity (48% to 67%) to known phytases. this high level of id ... | 1997 | 9349716 |
| chromosome rearrangements in neurospora and other filamentous fungi. | knowledge of fungal chromosome rearrangements comes primarily from n. crassa, but important information has also been obtained from a. nidulans and s. macrospora. rearrangements have been identified in other sordaria species and in cochliobolus, coprinus, magnaporthe, podospora, and ustilago. in neurospora, heterozygosity for most chromosome rearrangements is signaled by the appearance of unpigmented deficiency ascospores, with frequencies and ascus types that are characteristic of the type of r ... | 1997 | 9348657 |
| null alleles of crea, the regulator of carbon catabolite repression in aspergillus nidulans. | crea is the major regulatory protein involved in carbon catabolite repression in aspergillus nidulans. previously we have reported the molecular characterization of a number of in vivo selected mutant alleles and showed that they were unlikely to represent total loss of function alleles (shroff et al., 1996) and that a deletion of the crea gene and surrounding dna has an extremely severe effect on morphology under both carbon catabolite repressing and carbon catabolite nonrepressing conditions ( ... | 1997 | 9344629 |
| the duplication cycle in aspergillus nidulans. | the duplication cycle encompasses the spectrum of events required for the growth and division of individual cells within a fungal hyphae. recent advances in understanding the mechanisms which underlie nuclear division and cellular morphogenesis in the filamentous fungus aspergillus nidulans have shown that in many respects, the duplication cycle differs significantly from the cell cycles of both budding and fission yeast. the purpose of this review is to summarize these advances and to highlight ... | 1997 | 9344627 |
| molecular genetics of sulfur assimilation in filamentous fungi and yeast. | the filamentous fungi aspergillus nidulans and neurospora crassa and the yeast saccharomyces cerevisiae each possess a global regulatory circuit that controls the expression of permeases and enzymes that function both in the acquisition of sulfur from the environment and in its assimilation. control of the structural genes that specify an array of enzymes that catalyze reactions of sulfur metabolism occurs at the transcriptional level and involves both positive-acting and negative-acting regulat ... | 1997 | 9343344 |
| trichoderma reesei sequences that bind to the nuclear matrix enhance transformation frequency. | three dna fragments, trs1, 2 and 3, were isolated from the trichoderma reesei genome on the basis of their ability to promote autonomous replication of plasmids in saccharomyces cerevisiae. each trs element bound specifically to the isolated t. reesei nuclear matrix in vitro, and two of them bound in vivo, indicating that they are matrix attachment regions (mars). a similar sequence previously isolated from aspergillus nidulans (ans1) was also shown to bind specifically to the t. reesei nuclear ... | 1997 | 9341675 |
| inducible expression of yeast mitochondrial citrate synthase in aspergillus nidulans. | the coding region of the mitochondrial citrate synthase gene (cit1) from saccharomyces cerevisiae was amplified by pcr and cloned into an expression vector (pal4) downstream of the alcohol dehydrogenase (alca) promoter of aspergillus nidulans to yield palcs1. transformation of a. nidulans a773 with this construct gave stable transformants, ayc#1 and ayc#2, that were phenotypically stable for several mitotic divisions. southern blot analysis showed that the cit1 gene was successfully integrated i ... | 1997 | 9339892 |
| dominant mutations affecting both sporulation and sterigmatocystin biosynthesis in aspergillus nidulans. | the initiation of conidiophore development in the filamentous fungus aspergillus nidulans is a complex process requiring the activities of several genes including flug, flba, flbb, flbc, flbd, and flbe. recessive mutations in any one of these genes result in greatly reduced expression of the brla developmental regulatory gene and a colony morphology described as fluffy. these fluffy mutants have somewhat diverse phenotypes but generally grow as undifferentiated masses of vegetative hyphae to for ... | 1997 | 9339347 |
| studies on cellulases of aspergillus nidulans mutants. | mutants were characterized as to their morphology, auxotrophy and cellulase production. no apparent correlation was evident among these characters. the degree of repression or enhancement of the three components of the cellulase enzyme in the mutants varied considerably, indicating their separate genetic control. considerable variations in the enzyme profiles of the mutants were observed as compared to the wild type. enzyme production was also found to be related to development. | 1997 | 9330668 |
| a model for the combined effects of temperature and salt concentration on growth rate of food spoilage molds. | we modeled mold growth on a solid culture medium at various temperatures and nacl concentrations by using five common food spoilage molds (penicillium roqueforti, trichoderma harzianum, paecilomyces variotii, aspergillus niger, and emericella nidulans). for the description of the growth rate (expressed as the increase in colony diameter per unit of time) as a function of temperature and nacl concentration, a six-parameter model has been developed. the model combines either the rosso-type or the ... | 1997 | 9327540 |
| unusual lack of internal mobility and fast overall tumbling in oxidized flavodoxin from anacystis nidulans. | anacystis nidulans flavodoxin, an electron-transfer protein containing a flavin mononucleotide (fmn) molecule as its prosthetic group, has a redox potential for the oxidized/semiquinone equilibrium close to that of free flavin. whereas the redox potential for the semiquinone/hydroquinone equilibrium is more negative. to gain an understanding of the contribution of mobility to redox potential modulation, we studied the backbone mobility of the oxidized a. nidulans flavodoxin at ph 6.6, 303 k by 1 ... | 1997 | 9325102 |
| aspergillus asexual reproduction and sexual reproduction are differentially affected by transcriptional and translational mechanisms regulating stunted gene expression. | the stunted protein (stuap) is a member of a family of transcription factors that regulate fungal development and cell cycle progression. regulated stua gene expression is required for correct cell pattern formation during asexual reproduction (conidiation) and for initiation of the sexual reproductive cycle in aspergillus nidulans. transcriptional initiation from two different promoters yields overlapping mrnas (stua alpha and stuabeta) that upon translation yield the same protein. here we show ... | 1997 | 9315680 |
| stuap is a sequence-specific transcription factor that regulates developmental complexity in aspergillus nidulans. | the aspergillus nidulans stunted protein (stuap) regulates multicellular complexity during asexual reproduction by moderating the core developmental program that directs differentiation of uninucleate, terminally differentiated spores from multinucleate, vegetative hyphae. stuap is also required for ascosporogenesis and multicellular development during sexual reproduction. stuap is a member of a family of fungal transcription factors that regulate development or cell cycle progression. further, ... | 1997 | 9312029 |
| isolation of aspergillus niger crea mutants and effects of the mutations on expression of arabinases and l-arabinose catabolic enzymes. | aspergillus niger mutants relieved of carbon repression were isolated from an area parental strain by selection of colonies that exhibited improved growth on a combination of 4-aminobutanoic acid (gaba) and d-glucose. in addition to derepression of the utilization of gaba as a nitrogen source in the presence of d-glucose, three of the four mutants also showed derepression of l-alanine and l-proline utilization. transformation of the mutants with the a. niger crea gene, encoding the repressor pro ... | 1997 | 9308182 |
| deletion of nudc, a nuclear migration gene of aspergillus nidulans, causes morphological and cell wall abnormalities and is lethal. | nuclear migration is required for normal development in both higher and lower eukaryotes. in fungi this process is mediated by cytoplasmic dynein. it is believed that this motor protein is anchored to the cell membrane and moves nuclei by capturing and pulling on spindle pole body microtubules. to date, four genes have been identified and shown to be required for this process in aspergillus nidulans. the nuda and nudg genes, respectively, encode the heavy and light chains of cytoplasmic dynein, ... | 1997 | 9307970 |
| aspergillus sporulation and mycotoxin production both require inactivation of the fada g alpha protein-dependent signaling pathway. | the filamentous fungus aspergillus nidulans contains a cluster of 25 genes that encode enzymes required to synthesize a toxic and carcinogenic secondary metabolite called sterigmatocystin (st), a precursor of the better known fungal toxin aflatoxin (af). one st cluster (stc) gene, aflr, functions as a pathway-specific transcriptional regulator for activation of other genes in the st pathway. however, the mechanisms controlling activation of aflr and synthesis of st and af are not understood. her ... | 1997 | 9305634 |
| the validity of the aspergillus nidulans linkage map. | the aspergillus nidulans linkage map is reviewed as a background to physical mapping by cosmid cross-hybridization and genome sequencing. dna-based methods depend on contiguity, so that the resulting maps are only as good as the weakest link, whereas each new marker added to a linkage map can provide independent confirmation of the positions of its neighbors. for all eight chromosomes of a. nidulans a reliable framework has been provided by analysis of mitotic crossing over, in many cases substa ... | 1997 | 9299197 |
| autonomous plasmid replication in aspergillus nidulans: ama1 and mate elements. | with few exceptions, in eukaryotic organisms the presence of a chromosomal replicator on a circular vector molecule is not sufficient to confer on it the ability to persist and replicate extrachromosomally. however, it is possible to isolate from genomes of some filamentous fungi dna fragments which can provide extrachromosomal maintenance of plasmids. in aspergillus nidulans, two functional classes of such sequences can be distinguished: effective plasmid replicators (e.g., ama1) and transforma ... | 1997 | 9290250 |
| multicellular ascomycetous fungal genomes contain more than 8000 genes. | fungi comprise a large monophyletic group of uni- and multicellular eukaryotic organisms in which many species are of economic or medical importance. fungal genomes are variable in size (13-42 mb), and multicellular species support true spatial and temporal cell-type-specific regulation of gene expression. in a 38.8-kb aspergillus nidulans contiguous genomic dna region, a transposable element and 12 potential genes were identified, 7 similar to genes in other organisms. this observation is consi ... | 1997 | 9290249 |
| the design of pooling experiments for screening a clone map. | we consider nonadaptive pooling designs for unique-sequence screening of a 1530-clone map of aspergillus nidulans. the map has the properties that the clones are, with possibly a few exceptions, ordered and no more than 2 of them cover any point on the genome. we propose two subdesigns of the steiner system s(3, 5, 65), one with 65 pools and approximately 118 clones per pool, the other with 54 pools and about 142 clones per pool. each design allows 1 or 2 positive clones to be detected, even in ... | 1997 | 9290242 |
| role of four major cellulases in triggering of cellulase gene expression by cellulose in trichoderma reesei. | the relative contributions of four major cellulases of trichoderma reesei (1,4-beta-d-glucan cellobiohydrolase i [cbh i], cbh ii, endo-1,4-beta-d-glucanase i [eg i], and eg ii) to the generation of the cellulase inducer from cellulose were studied with isogenic strains in which the corresponding genes (cbh1, cbh2, egl1, and egl2) had been deleted by insertion of the aspergillus nidulans amds marker gene. during growth on lactose (a soluble carbon source provoking cellulase gene expression), thes ... | 1997 | 9286982 |
| biotransformation of the flavonoid tiliroside to 7-methylether tiliroside: bioactivity of this metabolite and of its acetylated derivative. | incubation of kaempferol-3-o-beta-d-(6"-e-p-coumaroyl)-glucopyranoside (tiliroside) (1) with aspergillus nidulans gives the 7-methyl ether of tiliroside (2) which is a new compound. its structure is determined by spectroscopic methods. cytotoxic studies of 2 and of its acetylated derivative 2a were carried out in vitro against fourteen human leukemic cell lines. results clearly show that compound 2 is ineffective against all leukemic cell lines tested. on the contrary, compound 2a exhibited cyto ... | 1997 | 9284960 |
| lipases in autolysed cultures of filamentous fungi. | fifty-one fungi from different genera and strains were checked in plate to determine lipase activity in protein precipitates from their autolysed cultures. each of them was then analysed at 3.5, 6.5 and 9.2 ph units and, as a consequence, basic lipases with high activity at 9.2 ph were found after 1 h of incubation. only 25% of the studied fungi showed this lipase activity, among them the best producers were fungi from genus fusarium (47% of fungi had lipase activity). in addition to lipase acti ... | 1997 | 9281862 |
| evolution of transcription-regulating proteins: a brief, critical appraisal. | 1997 | 9280733 | |
| the zinc binuclear cluster activator alcr is able to bind to single sites but requires multiple repeated sites for synergistic activation of the alca gene in aspergillus nidulans. | the alca gene which is part of the recently identified ethanol regulon, is one of the most strongly inducible genes in aspergillus nidulans. its transcriptional activation is mediated by the alcr transactivator which contains a dna-binding domain belonging to the c6 zinc binuclear cluster family. alcr differs from the other members of this family by several features, the most striking characteristic being its binding to both symmetric and asymmetric dna sites with the same apparent affinity. how ... | 1997 | 9278448 |
| the sequence of palf, an environmental ph response gene in aspergillus nidulans. | to molecularly characterize the influence of external ph in the secretion of enzymes by filamentous fungi, we have cloned and sequenced the palf gene of aspergillus nidulans (an). an an wild-type (wt) chromosome vii-specific cosmid library was used to transform a palf15 mutant strain. selection for complementation was done on medium containing beta-glycerolphosphate as the sole pi source. two cosmids were identified (w2g08 and w4g12) and further subcloning of one cosmid (w2g08) defined a 5-kb ps ... | 1997 | 9272857 |
| the bimc family of kinesins: essential bipolar mitotic motors driving centrosome separation. | 1997 | 9268050 | |
| the aspergillus nidulans lysf gene encodes homoaconitase, an enzyme involved in the fungus-specific lysine biosynthesis pathway. | in filamentous fungi, lysine is synthesized via the alpha-aminoadipate pathway. in order to gain insight into this fungus-specific pathway (to date, no genes for enzymes of this pathway in filamentous fungi have been cloned) the lysine auxotrophic mutant lysf88 of aspergillus nidulans was studied. hplc and 1h-nmr analyses revealed that lysf88 accumulated homocitric acid in the culture supernatant. in addition, both the lysf88 mutant strain and lysf deletion strain (lysfko) described here showed ... | 1997 | 9268014 |
| acv synthetase: expression of amino acid activating domains of the penicillium chrysogenum enzyme in aspergillus nidulans. | fragments of acv synthetase of penicillium chrysogenum carrying partial activities of amino acid activation were expressed under the alca promoter in an acva-deletion mutant of aspergillus nidulans. the 210 kda domain a-beta-galactosidase fusion protein was partially cleaved to fragments of 200 and 97 kda. the domain a fragment and the 312 kda domain bc construct were identified by peptide specific antibodies and shown to catalyze alpha-aminoadipate-, cysteine-, and valine-dependent atp/[32p]ppi ... | 1997 | 9266851 |
| mycological and some physiological studies of keratinophilic and other moulds associated with sheep wool. | wool samples of 50 healthy sheep collected from different localities at ar' ar in saudi arabia were examined for the presence of keratinophilic and other fungi using the hair plate technique. forty-eight species and 2 varieties belonging to 20 genera were isolated on sabouraud's dextrose agar at 25 degrees c. two species of true dermatophytes were isolated: trichophyton terrestre and t. rubrum in low frequency of occurrence. chrysosporium, a well-know keratinophilic genus, was the predominant ge ... | 1997 | 9265769 |
| a protein encoded by a group i intron in aspergillus nidulans directly assists rna splicing and is a dna endonuclease. | some group i introns self-splice in vitro, but almost all are thought to be assisted by proteins in vivo. mutational analysis has shown that the splicing of certain group i introns depends upon a maturase protein encoded by the intron itself. however the effect of a protein on splicing can be indirect. we now provide evidence that a mitochondrial intron-encoded protein from aspergillus nidulans directly facilitates splicing in vitro. this demonstrates that a maturase is an rna splicing protein. ... | 1997 | 9256423 |
| evolution of transcription-regulating proteins: caveat lector! | the paper of hawkins et al. [gene 146 (1994) 145-158] reports incorrect descriptions of mutant phenotypes, omits mention of the absence of a highly relevant glutamine-binding site and contains sequence alignments which might mislead the reader. extensive sequence analysis reveals as untenable a central hypothesis of the paper concerning a possible evolutionary relationship between anthranilate synthetases and the transcription factors mediating nitrogen metabolite repression in fungi. | 1997 | 9253382 |
| fungal microflora biodiversity as a function of pollution in oued sebou (morocco). | an inventory of the fungal microflora present in sediments collected at 11 sites along oued sebou has been established. the influence of some climatic parameters (temperature, rainfall) and of pollution on the composition of the fungal communities has been questioned. emericella nidulans, eurotium amstelodami, neosartotya fisheri var. glabrum (ascomycetes), dreschslera biseptata (dematiaceae), penicillium citrinum (mucedinaceae) and phoma sp. (sphaeropsidale) can be considered as strains sensiti ... | 1997 | 9253167 |
| characterization of nima protein kinase in aspergillus nidulans. | 1997 | 9251045 | |
| aspergillus nidulans infection in a patient with chronic granulomatous disease. | aspergillus nidulans is one of the several species of aspergillus with low pathogenicity. the significant infections of a. nidulans in human have rarely been reported, almost exclusively in patients with chronic granulomatous disease (cgd). cgd is a primary immunodeficiency disease which results from the absence of the nadph oxidase in the phagocytic cells, leading to recurrent pyogenic infection and granuloma and abscess formation. here we report a fatal case a. nidulans infection in a six-year ... | 1997 | 9250922 |
| monoclonal antibodies as probes for fungal wall structure during morphogenesis. | three monoclonal antibodies (mabs), s4d1, s3b3 and s1e5, were produced from hybridoma cell lines raised from mice immunized with hyphal walls of neurospora crassa and one (pax-1) from mice immunized with hyphal walls of paxillus involutus. in immunofluorescence studies, the three n. crassa mabs recognized epitopes with different patterns of distribution at the hyphal surface of n. crassa. s4d1 recognized an epitope which was present on the surface of both conidia and hyphae; s3b3 recognized an e ... | 1997 | 9245814 |
| involvement of ntcb, a lysr family transcription factor, in nitrite activation of the nitrate assimilation operon in the cyanobacterium synechococcus sp. strain pcc 7942. | nitrite, either exogenously supplied or endogenously generated by nitrate reduction, activates transcription of the nitrate assimilation operon (nira-nrtabcd-narb) in synechococcus sp. strain pcc 7942 cells treated with l-methionine-dl-sulfoximine (an inhibitor of glutamine synthetase), in which there is no negative feedback resulting from fixation of the ammonium generated by nitrite reduction (kikuchi et al., j. bacteriol. 178:5822-5825, 1996). other transcription units related to nitrogen ass ... | 1997 | 9244251 |