PMID(sorted ascending)
specific components of the saga complex are required for gcn4- and gcr1-mediated activation of the his4-912delta promoter in saccharomyces cerevisiae.mutations selected as suppressors of ty or solo delta insertion mutations in saccharomyces cerevisiae have identified several genes, spt3, spt7, spt8, and spt20, that encode components of the saga complex. however, the mechanism by which saga activates transcription of specific rna polymerase ii-dependent genes is unknown. we have conducted a fine-structure mutagenesis of one widely used saga-dependent promoter, the delta element of his4-912delta, to identify sequence elements important for its ...199910101163
cloning and characterisation of the saga gene of aspergillus nidulans: a gene which affects sensitivity to dna-damaging agents.mutations within the saga gene of aspergillus nidulans cause sensitisation to dna-damaging chemicals but have no effect upon spontaneous or damage-induced mutation frequency. the saga gene was cloned on a 19-kb cosmid-derived fragment by functional complementation of a saga1 sagc3 double mutant; subsequently, a fragment of the gene was also isolated on a 3.9-kb genomic subclone. initial sequencing of a small section of the 19-kb fragment allowed the design of primers that were subsequently used ...199910102359
an aureobasidin a resistance gene isolated from aspergillus is a homolog of yeast aur1, a gene responsible for inositol phosphorylceramide (ipc) synthase activity.the aur1 gene of saccharomyces cerevisiae, mutations in which confer resistance to the antibiotic aureobasidin a, is necessary for inositol phosphorylceramide (ipc) synthase activity. we report the molecular cloning and characterization of the aspergillus nidulans aura gene, which is homologous to aur1. a single point mutation in the aura gene of a. nidulans confers a high level of resistance to aureobasidin a. the a. nidulans aura gene was used to identify its homologs in other aspergillus spec ...199910102364
nimo, an aspergillus gene related to budding yeast dbf4, is required for dna synthesis and mitotic checkpoint control.the nimo predicted protein of aspergillus nidulans is related structurally and functionally to dbf4p, the regulatory subunit of cdc7p kinase in budding yeast. nimop and dbf4p are most similar in their c-termini, which contain a pest motif and a novel, short-looped cys2-his2 zinc finger-like motif. dna labelling and reciprocal shift assays using ts-lethal nimo18 mutants showed that nimo is required for initiation of dna synthesis and for efficient progression through s phase. nimo18 mutants abrog ...199910194410
alix, a novel mouse protein undergoing calcium-dependent interaction with the apoptosis-linked-gene 2 (alg-2) protein.alg-2 is a ef hand calcium binding protein with sequence homologies to calmodulin. vito et al have shown that alg-2 expression is required for apoptosis following a number of death stimuli,1 although nothing is known about the effectors which underlie alg-2 function. here we have used alg-2 as bait in a yeast two hybrid screen of a mouse brain cdna library. we found that alg-2 binds to itself and to a novel protein that we call alg-2 interacting protein x, alix. using co-immunoprecipitation expe ...199910200558
the gene that determines resistance to tioconazole and to acridine derivatives in aspergillus nidulans may have a corresponding gene in trichophyton rubrum.understanding the genetic mechanisms involved in resistance to antifungal agents is important in the fight against pathogenic fungi. in the present investigation we studied a strain of the model fungus aspergillus nidulans which presents resistance to tioconazole and behaves as the wild strain in the presence of other azole derivatives. genetic analysis revealed that this resistance is due to a mutation in a single gene located on chromosome ii, closely linked to the allele responsible for resis ...199810205888
functional analysis of upstream regulating regions from the yarrowia lipolytica xpr2 promoter.the xpr2 gene from yarrowia lipolytica encodes an inducible alkaline extracellular protease. its complex regulation involves ph, carbon, nitrogen and peptones. two previously identified upstream activating sequence (uas) regions were analysed in a reporter system, outside the xpr2 context. fragments from the uas regions were inserted upstream of a minimal leu2 promoter directing the expression of a reporter gene. the activity of the hybrid promoters was assessed following integration into the y. ...199910206713
[fungal flora in chicken stalls and its etiopathogenic importance for humans and animals].in order to find out the mycoflora prevailing in chicken pens, and to appreciate the health hazards for employees (incl. veterinarians) and animals, twenty litter samples and 6 sedimented dust trials were analysed mycologically. the following results were found: bedding and dust samples all contained between 3.57 and 1.30 x 10(7) c.f.u./g dw. the commonest fungus is a. fumigatus with 3.41 x 10(4) - 1.30 x 10(7) c.f.u./g dw in bedding and 2.70 x 10(5) - 3.30 x 10(6) c.f.u./g dw in sedimented dust ...199910209909
ectopic expression of the aspergillus nidulans mitotic inducer, nima kinase, in megakaryocytes: effect on polyploidization.aspergillus nidulans nima gene encodes a serine/threonine protein kinase (nima) whose activity is essential for mitotic entry and chromatin condensation. both the activity and the abundance of nima protein increase at the g2/m transition of the fungal cell cycle. in this study, we report the effects elicited by ectopic expression of nima on polyploidization in a mouse megakaryocytic line, y10, which is undergoing an endomitotic cell cycle. a pool of y10 stable transfectants that have been induce ...199910210317
a homolog of the fungal nuclear migration gene nudc is involved in normal and malignant human hematopoiesis.the filamentous fungus aspergillus nidulans nudc gene has an essential function in movement of nuclei following mitosis and is required for normal colony growth. here, the molecular cloning and role in hematopoiesis of a human gene (designated hnudc) homologous to a. nidulans nudc is reported. the amino terminus of the larger human protein (hnudc = 45 kda) does not overlap with a. nidulans nudc (22 kda). however, nudc and the c-terminal 94 amino acids of hnudc are 67% identical. the c-terminal r ...199910210332
binding of the c6-zinc cluster protein, aflr, to the promoters of aflatoxin pathway biosynthesis genes in aspergillus parasiticus.aflr is a zn2cys6-type sequence-specific dna-binding protein that is thought to be necessary for expression of most of the genes in the aflatoxin pathway gene cluster in aspergillus parasiticus and a. flavus, and the sterigmatocystin gene cluster in a. nidulans. however, it was not known whether aflr bound to the promoter regions of each of the genes in the cluster. recently, a. nidulans aflr was shown to bind to the motif 5'-tcgn5cga-3'. in the present study, we examined the binding of aflr to ...199910216264
the function of crea, the carbon catabolite repressor of aspergillus nidulans, is regulated at the transcriptional and post-transcriptional level.the crea gene of a. nidulans encodes a wide-domain regulatory protein mediating carbon catabolite repression. northern blot analysis of crea mrna revealed a complex expression profile: the addition of monosaccharides to a carbon-starved culture of a. nidulans provoked a strong transient stimulation of crea transcript formation within a few minutes. in the case of repressing carbon sources, crea mrna levels were subsequently downregulated, whereas the high crea mrna levels were maintained in a cr ...199910216870
the abfb gene encoding the major alpha-l-arabinofuranosidase of aspergillus nidulans: nucleotide sequence, regulation and construction of a disrupted strain.using a dna fragment containing the aspergillus niger abfb gene as a probe, the homologous aspergillus nidulans gene, designated abfb, has been cloned from a genomic library containing size-selected hindiii fragments. the nucleotide sequence of the a. nidulans abfb gene shows strong homology with the a. niger abfb, trichoderma reesei abf-1 and trichoderma koningii alpha-l-arabinofuranosidase/beta-xylosidase genes. regulation of abfb expression has been investigated in cultures induced with l-ara ...199910217508
identification of a novel nutrient-deprivation-induced sinorhizobium meliloti gene (hmga) involved in the degradation of tyrosine.sinorhizobium meliloti strain n4 carries a tn5luxab insertion in a gene which is induced by nitrogen and carbon deprivation as well as in the presence of tyrosine. the tn5luxab-tagged locus was found to share significant similarity with the human hmga gene and the corresponding aspergillus nidulans gene, encoding the enzyme homogentisate dioxygenase, which is involved in the degradation of tyrosine. extended dna sequence analysis of the tagged locus revealed the presence of several orfs, includi ...199910220173
transformation of the nematode-trapping fungus arthrobotrys oligospora.the nematode-trapping fungus arthrobotrys oligospora was transformed to hygromycin resistance using the hygromycin-b phosphotransferase gene from escherichia coli under the control of various heterologous fungal promoters. plasmid dna was introduced into fungal protoplasts by polyethylene glycol/cacl2 treatment. transformation frequencies varied between 1-6 transformants per microgram dna. seven out of 13 integration events analyzed from transformants were single copy integrations, whereas the r ...199910220888
a mitogen-activated protein kinase (mpka) is involved in polarized growth in the filamentous fungus, aspergillus aspergillus nidulans kinase gene, which encodes a protein kinase with high similarity to mitogen-activated protein kinases involved in cell wall construction and morphogenesis in yeast species, was cloned and sequenced. targeted deletion of the aspergillus nidulans kinase gene indicates that this kinase is involved in germination of conidial spores and polarized growth. these defects were largely remedied on complex high osmolarity media, although abnormal swellings of hyphal tips were still ...199910220889
cloning and characterization of the murine nek3 protein kinase, a novel member of the nima family of putative cell cycle regulators.we have cloned and characterized murine nek3 (nima-related kinase 3), a novel mammalian gene product structurally related to the cell cycle-regulatory kinase nima of aspergillus nidulans. by rnase protection, low levels of nek3 expression could be detected in all organs examined, regardless of proliferative index. in contrast to nek1 and nek2, nek3 levels were not particularly elevated in either the male or the female germ line. nek3 levels showed at most marginal variations through the cell cyc ...199910224116
zinc-regulated biosynthesis of immunodominant antigens from aspergillus spp.aspnd1 and aspf2 are immunodominant antigens from aspergillus nidulans and a. fumigatus, respectively, that are readily synthesized in infections in the human host, as demonstrated by their reactivity with more than 80% of sera from patients with aspergilloma or allergic bronchopulmonary aspergillosis. we demonstrate here that both antigens are exclusively produced under situations of low bioavailability of free zn2+. addition of micromolar concentrations of zn2+ to the culture medium strongly s ...199910225898
neutral trehalases catalyse intracellular trehalose breakdown in the filamentous fungi aspergillus nidulans and neurospora crassa.a camp-activatable ca2+-dependent neutral trehalase was identified in germinating conidia of aspergillus nidulans and neurospora crassa. using a pcr approach, a. nidulans and n. crassa genes encoding homologues of the neutral trehalases found in several yeasts were cloned and sequenced. disruption of the antreb gene encoding a. nidulans neutral trehalase revealed that it is responsible for intracellular trehalose mobilization at the onset of conidial germination, and that this phenomenon is part ...199910320571
the multiply-regulated gaba gene encoding the gaba permease of aspergillus nidulans: a score of exons.we describe the cloning, sequence and expression of gaba, encoding the gamma-amino-n-butyrate (gaba) permease of the fungus aspergillus nidulans. sequence changes were determined for three up-promoter (gabi ) and six gaba loss-of-function mutations. the predicted protein contains 517 residues and shows 30.3% overall identity with a putative gaba permease of arabidopsis thaliana, 29.6% identity with the yeast choline transporter and 23.4% identity with the yeast uga4 gaba permease. structural pre ...199910320578
disruption of phaca, an aspergillus nidulans gene encoding a novel cytochrome p450 monooxygenase catalyzing phenylacetate 2-hydroxylation, results in penicillin overproduction.aspergillus nidulans utilizes phenylacetate as a carbon source via homogentisate, which is degraded to fumarate and acetoacetate. mutational evidence strongly suggested that phenylacetate is converted to homogentisate through two sequential hydroxylating reactions in positions 2 and 5 of the aromatic ring. using cdna substraction techniques, we have characterized a gene, denoted phaca, whose transcription is strongly induced by phenylacetate and which putatively encodes a cytochrome p450 protein ...199910329644
arabidopsis fusca5 encodes a novel phosphoprotein that is a component of the cop9 complex.the cop9 complex is a regulator essential for repression of light-mediated development in arabidopsis. using partial amino acid sequence data generated from purified cop9 complexes, we cloned the arabidopsis cdna encoding the 27-kd subunit of the cop9 complex and showed that it is encoded by the previously identified fusca5 (fus5) locus. fus5 mutants exhibit constitutive photomorphogenic phenotypes similar to those of cop9 and fus6. point mutations in fus5 that led to a loss of fus5 protein were ...199910330469
occlusion of the internal carotid artery by means of microcoils for preventing epistaxis caused by guttural pouch mycosis in horses.occlusion of the internal carotid artery by insertion of intravascular platinum microcoils for guttural pouch mycosis was experimentally evaluated in 9 healthy adult thoroughbred horses. the internal carotid artery was ligated to its origin, and an arteriotomy was made distal to the ligature, which was then occluded by insertion of the microcoil approximately 13 cm distal to its origin. cessation of blood flow was determined visually and by angiography at the arteriotomy site. six horses were ev ...199910331192
modulation of polyketide synthase activity by accessory proteins during lovastatin biosynthesis.polyketides, the ubiquitous products of secondary metabolism in microorganisms, are made by a process resembling fatty acid biosynthesis that allows the suppression of reduction or dehydration reactions at specific biosynthetic steps, giving rise to a wide range of often medically useful products. the lovastatin biosynthesis cluster contains two type i polyketide synthase genes. synthesis of the main nonaketide-derived skeleton was found to require the previously known iterative lovastatin nonak ...199910334994
stress signaling from the lumen of the endoplasmic reticulum: coordination of gene transcriptional and translational controls. 199910346810
the carboxy-terminal portion of the aflatoxin pathway regulatory protein aflr of aspergillus parasiticus activates gal1::lacz gene expression in saccharomyces cerevisiae.aflr, a dna-binding protein of 444 amino acids, transactivates the expression of aflatoxin biosynthesis genes in aspergillus parasiticus and aspergillus flavus, as well as the sterigmatocystin synthesis genes in aspergillus nidulans. we show here by fusion of various aflr coding regions to the gal4 dna-binding coding region that the aflr carboxyl terminus contained a region that activated gal1::lacz gene expression in saccharomyces cerevisiae and that the aflr internal region was required for th ...199910347035
activity of the human centrosomal kinase, nek2, depends on an unusual leucine zipper dimerization motif.nek2 is a human cell cycle-regulated kinase that is structurally related to the mitotic regulator, nima, of aspergillus nidulans. localization studies have shown that nek2 is a core component of the centrosome, the microtubule organizing center of the cell, and functional approaches suggest a possible role for nek2 in centrosome separation at the g2/m transition. here, we have investigated the importance of an unusual leucine zipper coiled-coil motif present in the c-terminal noncatalytic domain ...199910347187
genetic analysis of aspergillus nidulans unstable transformants obtained by the biolistic process.mitotically unstable aspergillus nidulans argb+ transformants obtained by the biolistic process were studied in the present work. hybridization signals from undigested dna and pulsed-field chromosomal bands of the transformants suggested the introduced plasmid occurred as free concatenated molecules. fifteen vigorous growth sectors released from the transformants were analysed in order to understand the mechanisms involved in their formation. all sectors showed the integration of exogenous genes ...199810347861
the early nodulin gene mtn6 is a novel marker for events preceding infection of medicago truncatula roots by sinorhizobium meliloti.mtn6 belongs to a series of cdna clones representing medicago truncatula genes transcriptionally activated during nodulation by sinorhizobium meliloti (p. gamas, f. de carvalho niebel, n. lescure, and j. v. cullimore, mol. plant-microbe interact. 9:233-242, 1996). we show here by in situ hybridization that mtn6 transcripts specifically accumulate first at very localized regions in the outer root cell layers, corresponding to outer cortical cells containing preinfection threads. at later stages, ...199910356802
aroma improving in microvinification processes by the use of a recombinant wine yeast strain expressing the aspergillus nidulans xlna gene.a recombinant wine yeast strain has been constructed expressing the gene coding for beta-(1,4)-endoxylanase from aspergillus nidulans under the control of the yeast actin gene promoter. the resulting recombinant strain is able to secrete active xylanase enzyme into the culture medium. wines obtained by microvinification with the control and the recombinant wine yeast strain did not differ in their physicochemical characteristics although an increase in fruity aroma was organoleptically detected ...199910359487
sodvic is an alpha-cop-related gene which is essential for establishing and maintaining polarized growth in aspergillus nidulans.strains of aspergillus nidulans carrying the conditional-lethal mutation sodvic1 (stabilization of disomy) are defective in nuclear division and hyphal extension. the mutation affects both the establishment and maintenance of polar growth, since mutant spores do not germinate at restrictive temperature and preexisting hyphae stop growing upon upshift. the defect is reversible within the first 3-4 h at restrictive temperature but longer periods of incubation are lethal due to cell lysis and morph ...199910361037
carbon regulation of ribosomal genes in neurospora crassa occurs by a mechanism which does not require cre-1, the homologue of the aspergillus carbon catabolite repressor, crea.transcription of the ribosomal protein and 40s rrna genes is coordinately regulated during steady state growth and carbon shifts in neurospora crassa. recognition sequences for the aspergillus nidulans carbon catabolite repressor, crea, overlap transcriptional elements of a 40s rrna gene and the crp-2 ribosomal protein gene. they also occur in similar locations in the promoters of several other ribosomal protein genes. substitutions encompassing the -74 and -167 crea consensus sequences in the c ...199910361038
intrabronchial aspergillus nidulans infection in an immunocompetent man.we describe the first report of intrabronchial aspergillus nidulans infection in an immunocompetent patient, which fit the description of bronchocentric granulomatosis. the patient had a history of accidental aspiration of light grade oil. fiberoptic bronchoscopy revealed that the right b4aii alpha was obstructed. endobronchial biopsy specimens contained fungal hyphae. the fungus was confirmed to be aspergillus nidulans by culture. we suspected that aspiration of light grade oil had injured the ...199910361913
proliferation of intrahyphal hyphae caused by disruption of csma, which encodes a class v chitin synthase with a myosin motor-like domain in aspergillus nidulans.we have found that the aspergillus nidulans csma gene encodes a novel protein which consists of an n-terminal myosin motor-like domain and a c-terminal chitin synthase domain (m. fujiwara, h. horiuchi, a. ohta, and m. takagi, biochem. biophys. res. commun. 236:75-78, 1997). to clarify the roles of csma in fungal morphogenesis, we constructed csma null mutants. the growth rate of the mutant colonies was almost the same as that of the wild-type strain, but hyphal growth was severely inhibited when ...199910368147
the acuh gene of aspergillus nidulans, required for growth on acetate and long-chain fatty acids, encodes a putative homologue of the mammalian carnitine/acylcarnitine carrier.the aspergillus nidulans acuh gene, required for growth on acetate and long-chain fatty acids, was cloned by complementation of the acuh13 mutation. northern blotting analysis showed that transcription of the acuh gene occurs in acetate-grown mycelium and at higher levels in oleate-grown mycelium, but not during growth on glucose minimal medium. the acuh gene encodes a protein of 326 amino acids that belongs to the mitochondrial carrier family. the acuh protein contains three related segments of ...199910369894
crea modulates the xlnr-induced expression on xylose of aspergillus niger genes involved in xylan degradation.the expression of the feruloyl esterase gene faea, the alpha-glucuronidase gene agua, the endoxylanase gene xlnb, and the beta-xylosidase gene xlnd from aspergillus niger on xylose was studied in a wild-type strain and in a crea mutant. a decrease in expression of all four genes was observed with increasing xylose concentrations in the wild-type strain, whereas expression levels in the crea mutant were not influenced. the results in the wild type indicated that xylose concentrations higher than ...199910376490
changes in aspergillus nidulans gene expression induced by bafilomycin, a streptomyces-produced natural environments bacteria and filamentous fungi often compete for the same resources. consequently, production of antibiotic secondary metabolites and defence mechanisms against these compounds have evolved in these organisms. an experimental model has been developed to study the response in fungi exposed to one such antibiotic. the filamentous fungus aspergillus nidulans was treated with bafilomycin b1, a streptomyces-produced antibiotic which reduces radial growth rate and induces morph ...199910376827
extrachromosomal genetic elements in fungi. 199910379401
taf25p, a non-histone-like subunit of tfiid and saga complexes, is essential for total mrna gene transcription in vivo.we demonstrate, utilizing a temperature conditional mutant allele of the gene encoding taf25p, that this non-histone-like tbp-associated factor, which is shared between the tfiid and saga complexes, is required for bulk mrna gene transcription by rna polymerase ii in vivo. immunoblotting experiments indicate that at the restrictive temperature, inactivation of taf25p function results in a reduction of the levels of numerous tfiid and saga subunits, indicating its loss of function, like the histo ...199910383379
eukaryotic molybdopterin synthase. biochemical and molecular studies of aspergillus nidulans cnxg and cnxh mutants.we describe the primary structure of eukaryotic molybdopterin synthase small and large subunits and compare the sequences of the lower eukaryote, aspergillus nidulans, and a higher eukaryote, homo sapiens. mutants in the a. nidulans cnxg (encoding small subunit) and cnxh (large subunit) genes have been analyzed at the biochemical and molecular level. chlorate-sensitive mutants, all the result of amino acid substitutions, were shown to produce low levels of molybdopterin, and growth tests suggest ...199910383438
structure and expression properties of the endo-beta-1,4-glucanase a gene from the filamentous fungus aspergillus nidulans.endo-beta-1,4-glucanase a (eg a) of aspergillus nidulans was purified to homogeneity, and its genomic gene (egla) was cloned based on partial amino acid sequences of the purified enzyme and sequenced. the egla gene comprised 1228 bp with four putative introns and encoded a polypeptide of 326 amino acids bearing high homology to the family a cellulases. the egla promoter activity in a. nidulans was examined using the a. oryzae taka-amylase a gene as a reporter. expression of the reporter gene was ...199910386374
transcription of the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum is regulated by a gata-type transcription factor in aspergillus nidulans.the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum is highly induced during infection of tomato plants. expression of the avr9 gene can also be induced in vitro when cells are grown on synthetic liquid medium containing little or no nitrogen. the avr9 promoter contains six copies of the sequence tagata and six additional copies of the core sequence gata within 0.4 kb upstream of the translation start site. in the filamentous fungi aspergillus nidulans and neurospora crass ...199910394902
the glucose repressor cre1 from sclerotinia sclerotiorum is functionally related to crea from aspergillus nidulans but not to the mig proteins from saccharomyces cerevisiae.we isolated the putative glucose repressor gene cre1 from the phytopathogenic fungus sclerotinia sclerotiorum. cre1 encodes a 429 amino acid protein 59% similar to the carbon catabolite repressor crea from aspergillus nidulans. in addition to the overall amino acid sequence relatedness between cre1 and crea proteins, cre1 can functionally complement the a. nidulans cread30 mutation as assessed by repression of the alcohol dehydrogenase i gene expression. the crei region carrying the two zinc fin ...199910403374
molecular cloning and characterization of aspergillus nidulans cyclophilin b.cyclophilins are an evolutionarily conserved family of proteins which serve as the intracellular receptors for the immunosuppressive drug cyclosporin a. here we report the characterization of the first cyclophilin cloned from the filamentous fungus aspergillus nidulans (cypb). sequence analysis of the cypb gene predicts an encoded protein with highest homology to the murine cyclophilin b protein. the sequence similarity includes an n-terminal sequence predicted to target the protein to the endop ...199910413615
structural and transcriptional analysis of the pyrabcn, pyrd and pyrf genes in aspergillus nidulans and the evolutionary origin of fungal dihydroorotases.the six biochemical steps of the de novo pyrimidine biosynthesis pathway are conserved in all known organisms. however, in animals and fungi, unlike prokaryotes, at least the first two activities are grouped on a multifunctional enzyme. here, we report cloning, mapping and transcriptional characterization of some pyrimidine biosynthesis genes in the filamentous fungus aspergillus nidulans. the first two steps of the pathway are performed by a multifunctional enzyme comprising the activities of c ...199910417650
penicillin and cephalosporin biosynthesis: mechanism of carbon catabolite regulation of penicillin production.penicillins and cephalosporins are synthesized by a series of enzymatic reactions that form the tripeptide delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine and convert this tripeptide into the final penicillin or cephalosporin molecules. one of the enzymes, isopenicillin n synthase has been crystallyzed and its active center identified. the three genes pcbab, pcbc and pende involved in penicillin biosynthesis are clustered in penicillium chrysogenum, aspergillus nidulans and penicillium nalgiove ...199910422579
compartmentalization and transport in beta-lactam antibiotic biosynthesis by filamentous fungi.a proper description of the biosynthesis of fungal beta-lactam antibiotics requires detailed knowledge of the cell biology of the producing organisms. this involves a delineation of the compartmentalization of the biosynthetic pathways, and of the consequential transport steps across the cell-boundary plasma membrane and across organellar membranes. of the enzymes of the penicillin biosynthetic pathway in penicillium chrysogenum and aspergillus nidulans, delta-(l-alpha-aminoadipyl)-l-cysteinyl-d ...199910422581
gene organization and plasticity of the beta-lactam genes in different filamentous fungi.the genes pcbab, pcbc and pende encoding enzymes that catalyze the three steps of the penicillin biosynthesis have been cloned from penicillium chrysogenum and aspergillus nidulans. they are located in a cluster in penicillium chrysogenum, penicillium notatum, aspergillus nidulans and penicillium nalgiovense. the three genes are clustered in chromosome i (10.4 mb) of p. chrysogenum, in chromosome ii of p. notatum (9.6 mb) and in chromosome vi (3.0 mb) of a. nidulans. the cluster of the penicilli ...199910422582
transcriptional control of expression of fungal beta-lactam biosynthesis genes.the most commonly used beta-lactam antibiotics for the therapy of infectious diseases are penicillin and cephalosporin. penicillin is produced as end product by some fungi most notably by aspergillus (emericella) nidulans and penicillium chrysogenum. cephalosporins are synthesised by several bacteria and fungi, e.g. by the fungus acremonium chrysogenum (syn. cephalosporium acremonium). the biosynthetic pathways leading to both secondary metabolites start from the same three amino acid precursors ...199910422583
[biological characteristics of emericella nidulans isolated from horse guttural pouch mycosis].seven strains of emericella nidulans were isolated from lesions in the guttural pouch of horses with mycosis of this pouch. all strains grew in a wide range of temperature, ph and in five kinds of culture media. the optimum temperature that supported their growth was 38 degrees c, and all seemed to prefer an acidic environment with a ph of 4.0. proliferative conidial formation was found to be induced by the aforementioned temperature and ph. moreover, detection of beta-haemolysis and protease pr ...199910423512
sporogenic effect of polyunsaturated fatty acids on development of aspergillus spp.aspergillus spp. are frequently occurring seed-colonizing fungi that complete their disease cycles through the development of asexual spores, which function as inocula, and through the formation of cleistothecia and sclerotia. we found that development of all three of these structures in aspergillus nidulans, aspergillus flavus, and aspergillus parasiticus is affected by linoleic acid and light. the specific morphological effects of linoleic acid include induction of precocious and increased ase ...199910427064
the aroc gene of aspergillus nidulans codes for a monofunctional, allosterically regulated chorismate mutase.the cdna and the chromosomal locus of the aroc gene of aspergillus nidulans were cloned and is the first representative of a filamentous fungal gene encoding chorismate mutase (ec, the enzyme at the first branch point of aromatic amino acid biosynthesis. the aroc gene complements the saccharomyces cerevisiae aro7delta as well as the a. nidulans aroc mutation. the gene consists of three exons interrupted by two short intron sequences. the expressed mrna is 0.96 kilobases in length and a ...199910428795
unusual antimicrotubule activity of the antifungal agent spongistatin 1.spongistatin 1, a macrocyclic lactone from the marine sponge hyrtios erecta, has broad-spectrum antifungal activity. since this compound is a potent antimicrotubule agent in mammalian cells, we examined its effects on the filamentous fungus aspergillus nidulans to determine if its antifungal effects are due to antimicrotubule activity. at 25 microg/ml (twice the mic), spongistatin 1 caused a greater-than-twofold elevation of the chromosome and spindle mitotic indices. immunofluorescence microsco ...199910428925
the extremely conserved pyroa gene of aspergillus nidulans is required for pyridoxine synthesis and is required indirectly for resistance to photosensitizers.numerous disparate studies in plants, filamentous fungi, yeast, archaea, and bacteria have identified one of the most highly conserved proteins (snz family) for which no function was previously defined. members have been implicated in the stress response of plants and yeast and resistance to singlet oxygen toxicity in the plant pathogen cercospora. however, it is found in some anaerobic bacteria and is absent in some aerobic bacteria. we have cloned the aspergillus nidulans homologue (pyroa) of ...199910438537
functional analysis of dna sequences required for conidium-specific expression of the spoc1-c1c gene of aspergillus nidulans.the spoc1-c1c gene is centrally located within the a. nidulans conidium-specific spoc1 gene cluster. with one exception, the 14 genes within the cluster are coordinately regulated. c1c transcript is first detected late in conidiation, coincidental with the appearance of mature conidia, and accumulates approximately 1000-fold in conidia. we show that c1c expression is restricted to conidia, with mrna abundance decreasing immediately after induction of germination. c1c transcription and translatio ...199910441449
hap-like ccaat-binding complexes in filamentous fungi: implications for biotechnology.regulatory ccaat boxes are found frequently in eukaryotic promoter regions. they are bound by different ccaat-binding factors. until now, a single ccaat-binding complex has been reported in fungi. it is also found in higher eukaryotes and is highly conserved among eukaryotic organisms. this multimeric protein complex is designated hap, ancf, cbf, or nf-y. the complex consists of at least three subunits. in fungi, only the hap complex of saccharomyces cerevisiae had been known for a long time. th ...199910441450
species-specific production of microbial volatile organic compounds (mvoc) by airborne fungi from a compost facility.thirteen airborne fungal species frequently isolated in composting plants were screened for microbial volatile organic compounds (mvoc), i.e., aspergillus candidus, a. fumigatus, a. versicolor, emericella nidulans, paecilomyces variotii, penicillium brevicompactum, penicillium clavigerum, penicillium crustosum, penicillium cyclopium, penicillium expansum, penicillium glabrum, penicillium verruculosum, and tritirachium oryzae. air samples from pure cultures were sorbed on tenax gr and analyzed by ...199910448558
cloning and characterization of the gene encoding aspergillus nidulans dna topoisomerase ii.we have determined the complete nucleotide sequence of a 5544bp genomic dna fragment from aspergillus nidulans that encodes dna topoisomerase ii (topo ii). it contains a single open reading frame of 4740bp that codes for 1579 amino acid residues with a molecular weight of 178kda; when expressed in escherichia coli and saccharomyces cerevisiae the molecular weight was 180kda. the gene (top2) is divided into three exons. two introns, 54bp and 60bp in length, are located at nucleotide positions 187 ...199910452949
molecular cloning and characterization of the human nudc both aspergillus nidulans and the mouse, studies of the nuclear distribution gene c (nudc) have strongly suggested that the nudc protein interacts with nudf, which is the product of nudf, a homologue of human lis1 (also know as pafah1b1), one of the causative genes for classical lissencephaly. we have isolated the human nudc gene and its two processed pseudogenes. the human nudc gene is highly conserved and its predicted amino acid sequence shows 94% identity to mouse nudc and 95% identity to ...199910453739
histone acetyltransferase complexes can mediate transcriptional activation by the major glucocorticoid receptor activation domain.previous studies have shown that the ada adapter proteins are important for glucocorticoid receptor (gr)-mediated gene activation in yeast. the n-terminal transactivation domain of gr, tau1, is dependent upon ada2, ada3, and gcn5 for transactivation in vitro and in vivo. using in vitro techniques, we demonstrate that the gr-tau1 interacts directly with the native ada containing histone acetyltransferase (hat) complex saga but not the related ada complex. mutations in tau1 that reduce tau1 transa ...199910454542
novel human and mouse homologs of saccharomyces cerevisiae dna polymerase eta.the saccharomyces cerevisiae rad30 gene encodes a novel eukaryotic dna polymerase, pol eta that is able to replicate across cis-syn cyclobutane pyrimidine dimers both accurately and efficiently. very recently, a human homolog of rad30 was identified, mutations in which result in the sunlight-sensitive, cancer-prone, xeroderma pigmentosum variant group phenotype. we report here the cloning and localization of a second human homolog of rad30. interestingly, rad30b is localized on chromosome 18q21. ...199910458907
electrotransformation of the human pathogenic fungus scedosporium prolificans mediated by repetitive rdna sequences.the regions encoding the 5.8s rrna and the flanking internal transcribed spacers (itsi and itsii) from two isolates of the human pathogenic fungus scedosporium prolificans and one isolate of the taxonomically related species pseudallescheria boydii (s. apiospermum) were sequenced. the sequences of the two s. prolificans isolates were identical. however, there were minor differences between both species. phylogenetic analysis of known fungal sequences confirmed a close relationship between s. pro ...199910459582
sexual development of aspergillus nidulans in tryptophan auxotrophic strains.the interplay between sexual development and amino acid biosynthesis in the ascomycete aspergillus nidulans was studied. the growth and differentiation of four tryptophan auxotrophic strains that are unable to regulate their tryptophan biosynthesis, were examined. these strains are sterile on medium containing low tryptophan concentrations. fruitbody formation was restored by supplementation with high concentrations of tryptophan and was promoted by supplementation with indole or auxin. tryptoph ...199910460886
isolation of a new set of aspergillus nidulans mutants defective in nuclear the filamentous fungus aspergillus nidulans, nuclear migration in the germ tube is mediated by cytoplasmic dynein. we have previously reported the characterization of four nud (nuclear distribution) genes, nuda, nudc, nudf and nudg, involved in this process. the nuda and nudg genes respectively encode for the heavy chain and the 8-kda light chain of cytoplasmic dynein. in this work, we describe an improved method for the isolation of nud mutants that has led to the identification of at least ...199910467007
the metg gene of aspergillus nidulans encoding cystathionine beta-lyase: cloning and analysis.the metg gene of aspergillus nidulans encoding cystathionine beta-lyase, an enzyme of the main pathway of methionine synthesis, was cloned by complementation of a metg mutation. a comparison of metg genomic dna and a cdna copy derived from different a. nidulans strains revealed a marked dna sequence polymorphism manifested mostly by silent point mutations. cdna of the a. nidulans metg gene complemented the escherichia coli metc69 mutation impairing cystathionine beta-lyase. this gene contains tw ...199910467009
transcription: common cofactors and cooperative recruitment.mammalian counterparts of the yeast srb/med transcriptional 'mediator' complex have recently been identified. these complexes define a common cofactor requirement for diverse transcriptional activators and underscore the conserved nature of the transcriptional machinery among eukaryotic organisms.199910469586
the tama protein fused to a dna-binding domain can recruit area, the major nitrogen regulatory protein, to activate gene expression in aspergillus nidulans.the area gene of aspergillus nidulans encodes a gata zinc finger transcription factor that activates the expression of a large number of genes subject to nitrogen metabolite repression. the amount and activity of the area protein under different nitrogen conditions is modulated by transcriptional, post-transcriptional, and post-translational controls. one of these controls of area activity has been proposed to involve the nmra protein interacting with the dna-binding domain and the extreme c ter ...199910471703
molecular cloning and analysis of a pleiotropic regulatory gene locus from the nystatin producer streptomyces noursei atcc11455.a regulatory gene locus from streptomyces noursei atcc14455, the producer of the antifungal antibiotic nystatin, was cloned in streptomyces lividans based on its ability to activate actinorhodin (act) production in this host. deletion and dna sequencing analyses showed that a small gene, designated ssma, located downstream of an afsr homologue (a known pleiotropic regulator) was responsible for the act overproduction in s. lividans. database searches for the ssma gene product revealed its limite ...199910474196
ambient ph signal transduction in aspergillus: completion of gene characterization.completing the molecular analysis of the six pal genes of the ambient ph signal transduction pathway in aspergillus nidulans, we report the characterization of palc and palh. the derived translation product of palh contains 760 amino acids with prediction of seven transmembrane domains in its n-terminal moiety. remarkably, a palh frameshift mutant lacking just over half the palh protein, including almost all of the long hydrophilic region c-terminal to the transmembrane domains, retains some pal ...199910476033
the aspergillus niger acua and acub genes correspond to the faca and facb genes in aspergillus nidulans.mutants in aspergillus niger unable to grow on acetate as a sole carbon source were previously isolated by resistance to 1.2% propionate medium containing 0.1% glucose. acua mutants lacked acetyl-coa synthetase (acs) activity and acub mutants lacked both acs and isocitrate lyase activity. an acua mutant was transformed to the acu+ phenotype with a clone of acs (faca) from aspergillus nidulans. the acub mutant was transformed with the a. niger facb clone which has been identified by cross-hybridi ...199910483720
fungal utilization of organophosphate pesticides and their degradation by aspergillus flavus and a. sydowii in soil.fungal species were isolated which utilize organophosphate pesticides, viz. phosphorothioic (pirimiphos-methyl and pyrazophos), phosphorodithioic (dimethoate and malathion), phosphonic (lancer) and phosphoric (profenfos) acid derivatives. pesticide degradation was studied in vitro and in vivo (soil). aspergillus flavus, a. fumigatus, a. niger, a. sydowii, a. terreus, emericella nidulans, fusarium oxysporum and penicillium chrysogenum were isolated from pesticide-treated wheat straw. the number o ...199910489696
ancf, the ccaat binding complex of aspergillus nidulans, is essential for the formation of a dnase i-hypersensitive site in the 5' region of the amds gene.the ccaat sequence in the amds promoter of aspergillus nidulans is recognized by ancf, a complex consisting of the three evolutionary conserved subunits hapb, hapc, and hape. in this study we have investigated the effect of ancf on the chromatin structure of the amds gene. the ancf complex and the ccaat sequence were found to be necessary for the formation of a nucleosome-free, dnase i-hypersensitive region in the 5' region of the amds gene. deletion of the hape gene results in loss of the dnase ...199910490592
purification and characterization of 40-kda sterigmatocystin o-methyltransferase involved in aflatoxin biosynthesis.sterigmatocystin-o-methyltransferase (st-omtase), an enzyme catalyzing o-methylation of sterigmatocystin with s-adenosylmethionine (sam), was purified to electrophoretic homogeneity by immunoaffinity chromatography. a novel spectrofluorometric method was established to quantitatively determine the enzymatic activity of st-omtase. the purified protein, with a molecular weight of 40 kda by sds-page, was sensitive to thiol reagents and low concentrations of heavy metal ions. using a nutritional shi ...199910495468
lis1, the drosophila homolog of a human lissencephaly disease gene, is required for germline cell division and oocyte differentiation.lissencephaly is a severe congenital brain malformation resulting from incomplete neuronal migration. one causal gene, lis1, is homologous to nudf, a gene required for nuclear migration in a. nidulans. we have characterized the drosophila homolog of lis1 (lis1) and show that lis1 is essential for fly development. analysis of ovarian lis1 mutant clones demonstrates that lis1 is required in the germline for synchronized germline cell division, fusome integrity and oocyte differentiation. abnormal ...199910498683
essential role of the iron-regulated outer membrane receptor faua in alcaligin siderophore-mediated iron uptake in bordetella species.phenotypic analysis using heterologous host systems localized putative bordetella pertussis ferric alcaligin transport genes and fur-binding sequences to a 3.8-kb genetic region downstream from the alcr regulator gene. nucleotide sequencing identified a tonb-dependent receptor family homolog gene, faua, predicted to encode a polypeptide with high amino acid sequence similarity with known bacterial ferric siderophore receptors. in escherichia coli, the faua genes of both b. pertussis and bordetel ...199910498707
the nadp-dependent glutamate dehydrogenase gene from penicillium chrysogenum and the construction of expression vectors for filamentous fungi.the gdha gene encoding the nadp-dependent glutamate dehydrogenase activity from penicillium chrysogenum has been isolated and characterized for its use in gene expression. the nucleotide sequence of a 2816-bp genomic fragment was determined, showing an open reading frame of 1600 bp interrupted by two introns, of 160 bp and 57 bp respectively, with fungal consensus splice-site junctions. the predicted amino acid sequence revealed a high degree of identity to glutamate dehydrogenase enzymes, espec ...199910499259
the nit2 nitrogen regulatory protein of neurospora: expression and stability of nit-2 mrna and neurospora crassa, nit2 is a global transcription factor that positively regulates the expression of up to 100 genes that are related to nitrogen metabolism. nit2 is responsible for the lifting of nitrogen catabolite repression when the cellular levels of glutamine or other favored nitrogen sources become limited. immunoprecipitation of the nit2 protein showed that it is constitutively expressed, although its expression level is elevated a few-fold when nitrate instead of glutamine is used as ...199910501938
promoter-tagged restriction enzyme-mediated insertion (pt-remi) mutagenesis in aspergillus niger.promoter-tagged restriction enzyme-mediated insertion (pt-remi) mutagenesis was performed in the fungus aspergillus niger, using a plasmid containing a strong transcriptional promoter. two dna-tagged mutants were analyzed in detail. a white-spored mutant was shown to contain a plasmid insertion that disrupted a gene that shows a high degree of homology to the polyketide synthase gene wa of a. nidulans. a morphological mutant was shown to contain a plasmid insertion in the 5' upstream region of a ...199910503533
the aspergillus nidulans panb gene encodes ketopantoate hydroxymethyltransferase, required for biosynthesis of pantothenate and coenzyme a.ketopantoate hydroxymethyltransferase, which is encoded by the panb gene in the lower eukaryote aspergillus nidulans, is essential for the biosynthesis of coenzyme a, while the pathway intermediate 4'-phosphopantetheine is required for penicillin production. ketopantoate hydroxymethyltransferase could also serve as a target for anti-fungal drugs, since it is not present in mammals. clones of panb were identified by complementation of the corresponding mutant, and the dna sequence of the gene was ...199910503542
heterologous expression of pleurotus eryngii peroxidase confirms its ability to oxidize mn(2+) and different aromatic substrates.a versatile ligninolytic peroxidase has been cloned from pleurotus eryngii and its allelic variant mnpl2 expressed in aspergillus nidulans, with properties similar to those of the mature enzyme from p. eryngii. these include the ability to oxidize mn(2+) and aromatic substrates, confirming that this is a new peroxidase type sharing catalytic properties of lignin peroxidase and manganese peroxidase.199910508113
aspergillus nidulans mutants defective in stc gene cluster regulation.the genes involved in the biosynthesis of sterigmatocystin (st), a toxic secondary metabolite produced by aspergillus nidulans and an aflatoxin (af) precursor in other aspergillus spp., are clustered on chromosome iv of a. nidulans. the sterigmatocystin gene cluster (stc gene cluster) is regulated by the pathway-specific transcription factor aflr. the function of aflr appears to be conserved between st- and af-producing aspergilli, as are most of the other genes in the cluster. we describe a nov ...199910511551
deletion of the trichodiene synthase gene of fusarium venenatum: two systems for repeated gene deletions.the trichodiene synthase (tri5) gene of fusarium venenatum was cloned from a genomic library. vectors were created in which the tri5 coding sequence was replaced with the neurospora crassa nitrate reductase (nit3) gene and with the aspergillus nidulans acetamidase (amds) gene flanked by direct repeats. the first vector was utilized to transform a nitrate reductase (niad) mutant of f. venenatum to prototrophy, and the second vector was utilized to confer acetamide utilization to the wild-type str ...199910512673
the maturase encoded by a group i intron from aspergillus nidulans stabilizes rna tertiary structure and promotes rapid splicing.the ancob group i intron from aspergillus nidulans self-splices, providing the mg2+ concentration is >/= 15 mm. the splicing reaction is greatly stimulated by a maturase protein encoded within the intron itself. an initial structural and biochemical analysis of the splicing reaction has now been performed. the maturase bound rapidly to the precursor rna (kon approximately 3 x 10(9) m(-1) min(-1)) and remained tightly bound (koff </= 0.04 min(-1)). the catalytic step of 5' splice-site cleavage oc ...199910512698
a developmentally regulated gene cluster involved in conidial pigment biosynthesis in aspergillus fumigatus.aspergillus fumigatus, a filamentous fungus producing bluish-green conidia, is an important opportunistic pathogen that primarily affects immunocompromised patients. conidial pigmentation of a. fumigatus significantly influences its virulence in a murine model. in the present study, six genes, forming a gene cluster spanning 19 kb, were identified as involved in conidial pigment biosynthesis in a. fumigatus. northern blot analyses showed the six genes to be developmentally regulated and expresse ...199910515939
site-directed mutagenesis of arginine-89 supports the role of its guanidino side-chain in substrate binding by cephalosporium acremonium isopenicillin n synthase.isopenicillin n synthase (ipns) catalyses a key step in the penicillin and cephalosporin biosynthetic pathway which involves the oxidative cyclisation of the acyclic peptide delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) to isopenicillin n. based on crystallographic evidence from the aspergillus nidulans ipns crystal structure complexed with the substrate acv (roach et al. (1997) nature 387, 827-830), we were able to provide mutational evidence for the critical involvement of the conserv ...199910518746
the aspergillus nidulans sfad gene encodes a g protein beta subunit that is required for normal growth and repression of sporulation.flba encodes an aspergillus nidulans rgs (regulator of g protein signaling) domain protein that antagonizes fada (g(i)alpha-subunit of heterotrimeric g protein)-mediated growth signaling to allow asexual development. we previously defined and characterized five suppressors of flba (sfa) loss-of-function mutations and showed that one suppressor (sfab) resulted from a novel dominant-negative allele of fada. in this report we show that a second suppressor gene (sfad) is predicted to encode the beta ...199910523303
sequence analysis of the chitin synthase a gene of the dutch elm pathogen ophiostoma novo-ulmi indicates a close association with the human pathogen sporothrix schenckii.degenerate oligonucleotide primers were designed according to conserved regions of the chitin synthase gene family and used to amplify a 621 basepair (bp) fragment from genomic dna of ophiostoma novo-ulmi, the causal agent of dutch elm disease. the amplification product was used as a hybridization probe to screen a library of genomic dna sequences and to retrieve a full-length chitin synthase gene (chsa). the putative coding region of the gene was 2619 bp long, lacked introns, and encoded a poly ...199910524253
activity and substrate specificity of the murine stk2 serine/threonine kinase that is structurally related to the mitotic regulator protein nima of aspergillus nidulans.we isolated a murine stk2 (mstk2) cdna that is homologous to murine nek1 serine/threonine kinase, a family member related to the cell cycle regulator kinase nima of aspergillus nidulans. structural comparison demonstrated that the kinase domain of mstk2 is highly similar to nima/nek family but the c-terminal region is not similar to any proteins except for human stk2 (hstk2). similarly to nek1, mstk2 is expressed ubiquitously among various organs and is upregulated in the testis. the expression ...199910529384
genetic transformation and mutagenesis of the entomopathogenic fungus paecilomyces fumosoroseuswe have developed a dna-mediated transformation system for the entomopathogenic fungus paecilomyces fumosoroseus based on resistance to the herbicide glufosinate ammonium. the resistance is provided by the bar gene from streptomyces hygroscopicus and is under the control of the aspergillus nidulans trpc promoter and terminator sequences. frequencies of up to 110 transformants/&mgr;g of linearized plasmid dna were obtained aided by the addition of the nuclease inhibitor, aurintricarboxylic acid ( ...199910534416
morphogenesis is coordinated with nuclear division in germinating aspergillus nidulans conidiospores.germinating aspergillus nidulans conidiospores switch to polarized apical growth following an initial period of isotropic expansion. at the same time, they re-enter the nuclear division cycle. the relationship between spore polarization and nuclear division was investigated by testing the effect of cell cycle inhibitors and temperature-sensitive cell cycle mutations on spore morphogenesis. on rich media, it was found that spore polarization is delayed if completion of the first mitosis is blocke ...199910537196
expression and compartmentation of the glucose repressor cre1 from the phytopathogenic fungus sclerotinia sclerotiorum.the glucose repressor from the phytopathogenic fungus sclerotinia sclerotiorum is encoded by the cre1 gene. polyclonal antibodies were raised against a fusion protein (gluthathione s-transferase) gst-cre1 in order to study cre1 expression. western blot analyses revealed that cre1 synthesis is regulated by the nature of the extracellular carbon source. high cre1 levels are induced by glucose and remain stable after transfer into pectin medium, suggesting the existence of post-translational mechan ...199910542073
cloning and characterization of the o-methyltransferase i gene (dmta) from aspergillus parasiticus associated with the conversions of demethylsterigmatocystin to sterigmatocystin and dihydrodemethylsterigmatocystin to dihydrosterigmatocystin in aflatoxin biosynthesis.o-methyltransferase i catalyzes both the conversion of demethylsterigmatocystin to sterigmatocystin and the conversion of dihydrodemethylsterigmatocystin to dihydrosterigmatocystin during aflatoxin biosynthesis. in this study, both genomic cloning and cdna cloning of the gene encoding o-methyltransferase i were accomplished by using pcr strategies, such as conventional pcr based on the n-terminal amino acid sequence of the purified enzyme, 5' and 3' rapid amplification of cdna ends pcr, and ther ...199910543813
structure of the arginase coding gene and its transcript in aspergillus nidulans.the arginase structural gene (agaa) from aspergillus nidulans has been cloned and characterised. depending on the growth conditions of the mycelium, transcripts of this gene have different 5'ends. these differences could result either from the presence of multiple transcription initiation sites or from differential processing of mrna. the agaa mrna has a long 5'utr with a potentially complex secondary structure. putative arginine binding aptamers were found in this utr suggesting interesting pos ...199910547040
transcriptional activation by gcn4p involves independent interactions with the swi/snf complex and the srb/mediator.mutations in three subunits of the swi/snf complex and in the med2p subunit of the srb/mediator of pol ii holoenzyme impaired gcn4p-activated transcription of his3 without reducing gcn4p-independent transcription of this gene. recombinant gcn4p interacted with swi/snf and srb/mediator subunits in cell extracts in a manner dependent on the same hydrophobic clusters in the gcn4p activation domain; however, higher concentrations of gcn4p were required for binding to swi/snf versus srb/mediator subu ...199910549298
toxicological assessment of recombinant xylanase x(22) in wine.toxicological evaluation of xylanase x(22) from aspergillus nidulans expressed in a wine yeast strain was carried out. the safety of the x(22) intake was assessed by digestibility, bioinformatic, and mouse short-term repeated dosing studies, although x(22) shows resistance to proteolytic degradation in the gastrointestinal system, is a minority protein component (<0.5 10(-)(6) %) of the produced wine, and shows no significant amino acid sequence homology to any known food allergens. the 4-week o ...199910564023
checkpoint defects leading to premature mitosis also cause endoreplication of dna in aspergillus nidulans.the g2 dna damage and slowing of s-phase checkpoints over mitosis function through tyrosine phosphorylation of nimx(cdc2) in aspergillus nidulans. we demonstrate that breaking these checkpoints leads to a defective premature mitosis followed by dramatic rereplication of genomic dna. two additional checkpoint functions, uvsb and uvsd, also cause the rereplication phenotype after their mutation allows premature mitosis in the presence of low concentrations of hydroxyurea. uvsb is shown to encode a ...199910564263
inositol phosphoryl transferases from human pathogenic fungi.the ipc1 gene from saccharomyces cerevisiae, which encodes inositolphosphorylceramide (ipc) synthase, was first identified as a novel and essential gene encoding resistance to the natural product antifungal aureobasidin a (aur1). the formation of ipc in fungi is essential for viability, suggesting inhibitors of ipc1p function would make ideal antifungal drug candidates. homologs of the aur1/ipc1 gene were identified from a number of human pathogenic fungi, candida glabrata, candida krusei, candi ...200010564728
characterization of the n-linked glycosylation site of recombinant pectate lyase.recombinant pectate lyase from aspergillus niger was overexpressed in aspergillus nidulans. the two recombinant proteins produced differed in molecular mass by 1200 da, which suggested that the larger molecular weight protein was glycosylated. the deduced amino acid sequence was searched for potential n-linked glycosylation sites, and one potential site was identified at residue 64. the proteins were analyzed for their ability to bind various lectins as an assay for the presence of carbohydrates ...199910567938
sulfate transport in penicillium chrysogenum: cloning and characterization of the suta and sutb industrial fermentations, penicillium chrysogenum uses sulfate as the source of sulfur for the biosynthesis of penicillin. by a pcr-based approach, two genes, suta and sutb, whose encoded products belong to the sulp superfamily of sulfate permeases were isolated. transformation of a sulfate uptake-negative sb3 mutant of aspergillus nidulans with the sutb gene completely restored sulfate uptake activity. the suta gene did not complement the a. nidulans sb3 mutation, even when expressed under c ...199910572125
genetically structured modeling of protein production in filamentous fungi.a general framework for a genetically structured model is presented. the framework allows description of the interactions in a system of regulatory and structural genes. the model assumes equilibrium kinetics for the binding of regulatory proteins to the promoter regions of the genes and includes the possible activation of proteins following their synthesis. the model is evaluated by simulating the alca-expression (alcohol dehydrogenase i) in aspergillus nidulans which is an inducible system sub ...199910577470
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