| bioconversion of drimenol into 3 beta-hydroxydrimanes by aspergillus niger. effect of culture additives. | the bioconversion of (-)-drimenol [1] and drimenyl acetate [2] into the corresponding 3 beta-hydroxydrimanes by aspergillus niger in agitated liquid cultures was investigated. initial hydroxylation yields of 2% and 10%, respectively, were obtained. however, drimenyl acetate hydroxylation increased to 18% when carbopol-934 was added. the highest transformation yield (33%) was reached when an inclusion complex of drimenyl acetate to beta-cyclodextrin (1:1 w/w) was added to the cultures, after 48 h ... | 1993 | 8326324 |
| [frequency of bronchopulmonary isolation of aspergillus species in patients infected with human immunodeficiency virus: pathogenic role?]. | prevalence of aspergillosis in patients infected with the human immunodeficiency virus (hiv) is unknown. mycologic findings in bronchopulmonary specimens from 614 hiv-positive patients sent to a parasitology laboratory between june 1, 1989 and may 31, 1991 were analyzed retrospectively; medical records of aspergillus sp--positive patients were studied to evaluate the potential pathogenic role of this organism. prevalence of aspergillus sp. was 2.7% in bronchoalveolar lavage (bal) specimens, (21/ ... | 1993 | 8332393 |
| isolation and characterization of urease from aspergillus niger. | urease was purified (4126-fold) from aspergillus niger (nrrl 003) to a homologous enzyme preparation with a specific activity of 1341 mumol min-1 (mg protein)-1. one species of urease was detected in a. niger, with km = 3.0 mm, native molecular mass 250,000 da, ph optimum of 8.0 and a high specificity for urea. hydroxyurea was a strong competitive inhibitor of urease activity, while n-methylurea acted as a weak uncompetitive inhibitor, based on lineweaver-burk and eadie-hoftstee plots. the activ ... | 1993 | 8336111 |
| ferulic acid esterase from aspergillus niger: purification and partial characterization of two forms from a commercial source of pectinase. | two forms of ferulic acid esterase from aspergillus niger have been isolated from a commercial source of pectinase. one, designated i, has a m(r) of 132,000, is probably dimeric, and has a pi of 3.0. the second, designated ii, was partially purified and is monomeric (m(r) 29,000), with a pi of 3.6. both enzymes were free of pectinase and xylanase activity and released ferulic acid from methyl ferulate. in association with a xylanase, they also released ferulic acid from destarched wheat bran. fe ... | 1993 | 8338641 |
| synthesis and antifungal activity of medicagenic acid saponins on plant pathogens: modification of the saccharide moiety and the 23 alpha substitution. | the study of structure-antifungal activity relationships of medicagenic acid saponins was widened to include synthetic glycosides of mannose, galactose, cellobiose, and lactose as well as a 23 alpha-hydroxymethyl analog of medicagenic acid, namely, methyl 2 beta,3 beta-dihydroxy-23 alpha-hydroxymethyl-delta (12)-oleanene-28 beta-carboxylate, against sclerotium rolfsii, rhizoctonia solani, trichoderma viride, aspergillus niger, and fusarium oxysporum. the native glucose-containing saponin was a m ... | 1993 | 8339299 |
| expression of the glucose oxidase gene from aspergillus niger in hansenula polymorpha and its use as a reporter gene to isolate regulatory mutations. | the glucose oxidase gene (god) from aspergillus niger was expressed in hansenula polymorpha using the methanol oxidase promoter and transcription termination region and the mf-alpha leader sequence from saccharomyces cerevisiae to direct secretion. the expression cassette was cloned into the s. cerevisiae vector yep13 and used to transform h. polymorpha strain a16. in the initial transformants plasmid replication was unstable, but was stabilized by a growth regime consisting of alternating cycle ... | 1993 | 8346679 |
| immobilization of aspergillus niger nrc 107 xylanase and beta-xylosidase, and properties of the immobilzed enzymes. | aspergillus niger nrc 107 xylanase and beta-xylosidase were immobilized on various carriers by different methods of immobilization, including physical absorption, covalent binding, ionic binding, and entrapment. the immobilized enzymes were prepared by physical adsorption on tannin-chitosan, ionic binding onto dowex-50w, covalent binding on chitosan beads through glutaraldehyde, and entrapment in polyacrylamide had the highest activities. in most cases, the optimum ph of the immobilized enzymes ... | 1993 | 8346906 |
| the purification of commercially available endo-alpha-l-arabinanases and alpha-l-arabinosidase for use in the structural analysis of pectic polysaccharides. | | 1993 | 8348546 |
| fungal pathogens in etiology of septic shock in neutropenic patients with cancer (short communication). | during the 3 years from 1989 to 1991, we evaluated the etiology of septic shock cases and infection-associated mortality. a total number of 38 patients was included in the study, according to the criteria for septic shock (ss), (intensive care medicine society, 1989). in 1989, p. aeruginosa and enterobacteriaceae among the pathogens prevailed. in 1990 and 1991, s. aureus, enterococci and fungi were most frequent. from 8 patients with ss in 1990, the shock was due to candida albicans in 1 and to ... | 1993 | 8353326 |
| kinetics of glucose oxidase catalyzed electron transfer mediated by sulfur and selenium compounds. | unusually high electron transfer rates in aspergillus niger glucose oxidase catalyzed oxidation of glucose using 5,6:11,12-bis(dithio)tetracene (ttt), 1,2-dimethyltetraselenafulvalene (dmtsf) and tetrathiafulvalene (ttf) were observed. at ph 7.0 oxidation rate constants (tn/km) in the range from 1.0.10(7) to 8.7.10(7) m.s-1 were deduced from experimental data. one of the investigated mediators, dmtsf, has been used for electrocatalytical glucose oxidation on graphite at a potential of 0.3 v vs. ... | 1993 | 8354396 |
| the 3d structure of glucose oxidase from aspergillus niger. implications for the use of god as a biosensor enzyme. | the tertiary structure of glucose oxidase (god) from aspergillus niger was determined by x-ray crystallography (to be described elsewhere). the overall folding of the enzyme is described with regard to its application in biosensors, and conclusions are drawn from experiments on electrical communication between the enzyme and the electrodes. | 1993 | 8357574 |
| cloning of an aspergillus niger invertase gene by expression in trichoderma reesei. | the filamentous fungus aspergillus niger produces two glycosylated forms of the sucrose-hydrolysing enzyme, invertase. in contrast, some trichoderma species lack invertase and are unable to utilise sucrose as a sole carbon source. using an a. niger genomic library constructed in a cosmid vector containing the ura5 gene of podospora anserina as a selectable marker, and the t. reesei ura5- strain as a sucrose-minus recipient strain, an a. niger invertase gene (suc1) has been cloned by a sib select ... | 1993 | 8358832 |
| purification and characterisation of an aspergillus niger invertase and its dna sequence. | a secreted invertase was purified 23-fold by ultrafiltration, ion-exchange, and gel filtration chromatography from the culture supernatant of 18 h sucrose-grown cultures of aspergillus niger. the purified enzyme hydrolysed sucrose and raffinose but there was no detectable hydrolysis of inulin, melezitose or pnpg. invertase activity was optimal at ph 5.5 and 50 degrees c. the molecular mass of reduced invertase was 115 kda, as determined by sds gel electrophoresis. the native molecular weight of ... | 1993 | 8358833 |
| structural features of a polygalacturonase gene cloned from aspergillus oryzae kbn616. | a genomic gene encoding a polygalacturonase from aspergillus oryzae, used in soy sauce production, was cloned and sequenced. the structural gene comprises 1227 bp coding for 363 amino acids with a putative prepropeptide of 28 amino acids and the open reading frame is disrupted by two short introns of 57 bp and 81 bp. the deduced amino acid sequence of the mature protein showed 63, 63, 63 and 64% homology with those of aspergillus niger polygalacturonase i, aspergillus niger polygalacturonase ii, ... | 1993 | 8359678 |
| the aspergillus niger carbon catabolite repressor encoding gene, crea. | in order to undertake a comparative analysis of carbon catabolite repression in two aspergillus species, the crea gene has been isolated from a. niger by cross hybridization, using the cloned a. nidulans gene. the a. niger gene has been shown to be functional in a. nidulans by heterologous complementation of the crea204 mutation of a. nidulans. overall, the genes show 90% sequence similarity (82% identity) at the amino acid (aa) level. there were some striking similarities between the aa sequenc ... | 1993 | 8359691 |
| characterization of the pyruvate kinase-encoding gene (pki1) of trichoderma reesei. | the pyruvate kinase-encoding gene (pki1) from trichoderma reesei was isolated by hybridization to the corresponding aspergillus nidulans pkia gene. the 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. the coding sequence contains a single intron of 246 nt at a position identical to that of intron e in the a. nidulans gene. the pki protein shows extensive homology to the pkis of a. nidulans and a. niger (67%) and saccharomyces cerevisiae (59%). the 5' non-co ... | 1993 | 8359694 |
| aspergillus niger isolated in an outbreak of rhinitis in rats. | | 1993 | 8362472 |
| the role of the proton-pumping and alternative respiratory chain nadh:ubiquinone oxidoreductases in overflow catabolism of aspergillus niger. | mitochondria of fungi contain two respiratory chain enzymes concerned with the oxidation of matrix nadh. these are the proton-pumping nadh:ubiquinone oxidoreductase, also called complex i, which has a high affinity for nadh, and a non-proton-pumping nadh:ubiquinone oxidoreductase, called alternative nadh dehydrogenase, which has a low affinity for nadh. the role of these two enzymes in normal and overflow catabolism has been studied in aspergillus niger. three strains were investigated, the wild ... | 1993 | 8365409 |
| mycoflora and natural occurrence of mycotoxins in tobacco from cigarettes in egypt. | forty-two species and 4 varieties belonging to 21 genera were collected from 40 tobacco samples on glucose- and cellulose-czapek's agar at 28 degrees c and 45 degrees c. the most common mesophiles (at 28 degrees c) in tobacco on the two types of media were: aspergillus flavus, a. flavus var. columnaris, a. fumigatus, a. niger, penicillium chrysogenum and p. funiculosum. two samples were heavily contaminated with members of fusarium (f. moniliforme, f. oxysporum, f. solani). some fungi were encou ... | 1993 | 8368025 |
| the influence of heat and mass transfer on solid state fermentation. | | 1993 | 8372576 |
| immobilization of glucose oxidase on polyethylene film using a plasma induced graft copolymerization process. | an active glucose oxidase immobilized membrane was obtained via plasma induced graft copolymerization of acrylic acid on polyethylene film. plasma induced graft copolymerization of acrylic acid on polyethylene film has been prepared. this novel grafted polymer film for immobilizing glucose oxidase has been studied here. the carboxylic groups of the poly(acrylic acid) chains incorporated onto the polyethylene surface were utilized for further chemical immobilization of glucose oxidase by esterifi ... | 1993 | 8373750 |
| reaction mechanisms of trp120-->phe and wild-type glucoamylases from aspergillus niger. interactions with maltooligodextrins and acarbose. | interactions of wild-type and trp120-->phe glucoamylase with maltooligodextrin (gx) substrates and the tight-binding inhibitor acarbose (a) were investigated here using stopped-flow fluorescence spectroscopy and steady-state kinetic measurements. all wild-type and trp120-->phe glucoamylase reactions followed the three-step model e + gx(or a) (k1) <==> (k-1) egx (or a) (k2) <==> (k-2) e*gx(or a) (k3) --> e + p or e-a, previously shown to account for the glucoamylase-maltose system [olsen, k., sve ... | 1993 | 8373772 |
| alpha-galactosidase to prevent gas. | | 1993 | 8383798 |
| peritonitis due to aspergillus niger in a patient on continuous ambulatory peritoneal dialysis shortly after kidney graft rejection. | | 1993 | 8384344 |
| cloning, characterization and overexpression of the phytase-encoding gene (phya) of aspergillus niger. | phytase catalyzes the hydrolysis of phytate (myo-inositol hexakisphosphate) to myo-inositol and inorganic phosphate. a gene (phya) of aspergillus niger nrrl3135 coding for extracellular, glycosylated phytase was isolated using degenerate oligodeoxyribonucleotides deduced from phytase amino acid (aa) sequences. nucleotide (nt) sequence analysis of the cloned region revealed the presence of an open reading frame coding for 467 aa and interrupted once by an intron of 102 bp in the 5' part of the ge ... | 1993 | 8387447 |
| supplemental microbial phytase improves bioavailability of dietary zinc to weanling pigs. | two experiments were conducted to determine the effects of supplemental microbial phytase on utilization of dietary zinc by weanling pigs. experiment 1 was a 2 x 3 factorial arrangement of treatments with 24 pigs for 4 wk. two levels of phytase activity (0 and 1350 units/g) and three levels of zinc (0, 30 and 60 mg/kg as znso4.7h2o) were added to a corn-soybean meal basal diet. weekly measures included growth performance, plasma alkaline phosphatase activity and plasma mineral concentrations. in ... | 1993 | 8389400 |
| efficacy of phytase in improving the bioavailability of phosphorus in soybean meal and corn-soybean meal diets for pigs. | four experiments involving 225 pigs were conducted to assess the efficacy of a microbial phytase (finase, alko ltd. biotechnology, rajamäki, finland) produced by aspergillus niger in corn-soybean meal or dextrose-cornstarch-soybean meal-based diets. in two experiments with growing-finishing pigs, fortified corn-soybean meal diets were formulated to be adequate (.50%) or inadequate (.40 or .30%) in p during the growing phase followed by adequate (.40%) or inadequate (.30%) p in the finishing phas ... | 1993 | 8394307 |
| the efficacy of low temperature plasma (ltp) sterilization, a new sterilization technique. | the efficacy of low temperature plasma (ltp) sterilization, a newly developed sterilization procedure was tested. following experiments were carried out: determination of the most resistant test organism, influence of 10% and 20% defibrinated sheep blood or varying salt concentrations on the efficacy of the sterilization process, influence of the carrier position in the sterilization chamber and in the sterilization pouches, influence of a loaded sterilization chamber, comparative efficacy of eo ... | 1993 | 8397686 |
| screening of plants used in argentine folk medicine for antimicrobial activity. | screening of 132 extracts from argentine folk-medicinal plants for antimicrobial activity has been conducted using a penicillin g resistant strain of staphylococcus aureus, escherichia coli and aspergillus niger as test microorganisms. cephazolin, ampicillin and miconazole were used as standard antibiotics and concentration-response curves were obtained using the agar-well diffusion method. boiling water extracts of plant materials were tested and 12 species were active against staphylococcus au ... | 1993 | 8412245 |
| effects of antimycotics on the biosynthesis of cellular macromolecules in aspergillus niger protoplasts. | the effects of nine antimycotics on the biosynthesis of cellular macromolecules were analyzed using the regenerating system of protoplasts of aspergillus niger. the incorporation of several specific radioactive precursors into major cellular components were measured in the presence or in the absence of respective agents. miconazole, ketoconazole, and tolnaftate inhibited the lipid synthesis. 5-fluorocytosine strongly inhibited the dna and protein syntheses. griseofulvin, however, specifically in ... | 1993 | 8413497 |
| calcium oxalate crystal deposition in necrotizing otomycosis caused by aspergillus niger. | numerous calcium oxalate crystals were present within fruiting heads of aspergillus niger and among necrotic debris in a case of bilateral invasive otomycosis occurring in a diabetic female with end stage renal disease. this is the first report of in vivo calcium oxalate crystal deposition associated with aspergillus niger at this anatomic site. the presence of localized oxalate crystals within necrotic tissue from the external auditory canal is presumptive of otomycosis caused by aspergillus ni ... | 1993 | 8415598 |
| crystal structure of glucose oxidase from aspergillus niger refined at 2.3 a resolution. | glucose oxidase (beta-d-glucose: oxygen 1-oxidoreductase, ec 1.1.3.4) is an fad-dependent enzyme that catalyzes the oxidation of beta-d-glucose by molecular oxygen. the crystal structure of the partially deglycosylated enzyme from aspergillus niger has been determined by isomorphous replacement and refined to 2.3 a resolution. the final crystallographic r-value is 18.1% for reflections between 10.0 and 2.3 a resolution. the refined model includes 580 amino acid residues, the fad cofactor, six n- ... | 1993 | 8421298 |
| resonance raman spectroscopic evidence for an anionic flavin semiquinone in bovine liver monoamine oxidase. | the flavoprotein monoamine oxidase b (mao b) from bovine liver, as isolated, has an unusual additional absorption band at 412 nm, which is similar to the absorption of its anionic flavin semiquinone form, (fl.-), and other typical (fl.-) flavoproteins. denaturation of the enzyme results in the elimination of this anomalous absorption. the resonance raman (rr) spectrum of mao b as isolated is virtually identical to that of its dithionite-reduced (fl.-) form. both spectra show features similar to ... | 1993 | 8424650 |
| functional roles of the invariant aspartic acid 55, tyrosine 306, and aspartic acid 309 in glucoamylase from aspergillus awamori studied by mutagenesis. | three mutants, asp55-gly, tyr306-->phe, and asp309-->asn, of aspergillus awamori glucoamylase (identical to aspergillus niger glucoamylase) were constructed to elucidate the roles of two conserved regions within fungal glucoamylases. kinetic studies indicate that both of these regions are closely associated with activity. the asp55-->gly mutation decreases the kcat approximately 200 times toward maltose and isomaltose, while km values remain similar to the wild-type. this localizes asp55 to subs ... | 1993 | 8424940 |
| induction of extracellular arabinases on monomeric substrates in aspergillus niger. | the induction of extracellular arabinases by pentose sugars and polyols generated by the metabolic pathway of l-arabinose and d-xylose catabolism in aspergillus niger was investigated. induction occurred with l-arabinose and l-arabitol but not with d-xylose or xylitol. l-arabitol in particular was found to be a good inducer for alpha-l-arabinofuranosidase and endo-arabinase activities. western blotting analysis showed both alpha-l-arabinofuranosidase a and b to be present. no induction was obser ... | 1993 | 8427548 |
| cloning, characterization, and use in strain improvement of the cephalosporium acremonium gene cefg encoding acetyl transferase. | a long open reading frame (orf) closely linked to the cephalosporium acremonium gene cefef was identified by dna sequencing. the cefef gene encodes the enzyme involved in cephalosporin c (cpc) biosynthesis known as expandase/hydroxylase. complementation of a c. acremonium cefg mutant, as well as expression of the gene in aspergillus niger, showed this orf to be the cefg gene, encoding cephalosporin c acetyltransferase, which catalyzes the last step in cpc biosynthesis. analysis of transformants ... | 1993 | 8428381 |
| genetic maps of eight linkage groups of aspergillus niger based on mitotic mapping. | this paper provides a genetic map of aspergillus niger. at present 84 markers have been assigned to eight linkage groups. the chromosomal location of 60 markers is presented in this paper. the allocation of markers is based on recombination due to mitotic crossing over. various methods for selection and analysis of homozygous recombinants were applied, using colour, auxotrophic and resistance markers. in addition, transformants carrying the heterologous aspergillus nidulans gene coding for aceta ... | 1993 | 8428383 |
| refined structure for the complex of 1-deoxynojirimycin with glucoamylase from aspergillus awamori var. x100 to 2.4-a resolution. | the three-dimensional structure of the complex of 1-deoxynojirimycin with glucoamylase ii-(471) from aspergillus awamori var. x100 has been determined to 2.4-a resolution. the model includes residues corresponding to residues 1-471 of glucoamylase i from aspergillus niger, two molecules of bound 1-deoxynojirimycin and 605 sites for water molecules. the crystallographic r factor from refinement is 0.119, and the root-mean-squared deviation in bond distances is 0.012 a. the inhibitor complex confi ... | 1993 | 8431441 |
| functional roles and subsite locations of leu177, trp178 and asn182 of aspergillus awamori glucoamylase determined by site-directed mutagenesis. | fungal glucoamylases contain four conserved regions. one region from the aspergillus niger enzyme contains three key carboxylic acid residues, the general acid catalytic group, glu179, along with asp176 and glu180. three site-directed mutations, leu177-->his, trp178-->arg and asn182-->ala, were constructed near these acidic groups to reveal the function of other conserved residues in this region. leu177 and trp178 are strictly conserved among fungal glucoamylases, while an amide, predominantly a ... | 1993 | 8433972 |
| characterization of the gene encoding alpha-sarcin, a ribosome-inactivating protein secreted by aspergillus giganteus. | the filamentous fungus, aspergillus giganteus, produces the extracellular ribosome-inactivating protein, alpha-sarcin (sar). the structural gene (sar) encoding sar was isolated and characterized by sequence analysis and expression in aspergillus niger. it codes for a precursor of 177 amino acids containing a secretion signal sequence that is absent in the mature protein. the nucleotide sequence contains several typical features of fungal genes, including a short intron of 65 bp. the transcriptio ... | 1993 | 8444347 |
| effect of formulation ph and storage temperatures on the preservative efficacy of some gases used as propellants in cosmetic aerosols. | the effects of changes in formulation ph and storage temperature on the preservative activities of some aerosol propellants--butane, carbon dioxide, dimethylether and their combinations were investigated. a preservative challenge test method was used to determine the survival rates of escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, candida albicans and aspergillus niger at formulation ph levels 5.80, 7.28 and 8.10 and storage temperatures of 20 degrees, 30 degrees and 40 degrees ... | 1993 | 8444651 |
| cloning and characterisation of pepc, a gene encoding a serine protease from aspergillus niger. | we have cloned a gene, pepc, encoding a serine proteinase, pepc, from aspergillus niger by screening a phage lambda genomic dna library with a gene (prb1) from saccharomyces cerevisiae which codes for proteinase yscb. the nucleotide (nt) sequence of pepc revealed that the gene is composed of two exons of 369 nt and 1230 nt separated by a single 70-nt intron. the deduced protein of 533 amino acids (aa) has a putative signal sequence for transport into the endoplasmic reticulum. based on the exten ... | 1993 | 8449413 |
| isolation and characterization of the aspergillus oryzae gene encoding aspergillopepsin o. | we have cloned and determined the nucleotide sequence of a genomic dna segment from aspergillus oryzae which contains pepo, the gene encoding the aspartic proteinase, aspergillopepsin o (pepo). the organization of pepo is strikingly similar to that of pepa from a. niger var. awamori (previously called a. awamori) in that both are composed of four exons and three introns with virtually identical lengths, and the positions of the introns are exactly conserved. from the deduced amino acid (aa) sequ ... | 1993 | 8462873 |
| release of volatile branched-chain and other fatty acids from ruminant milk fats by various lipases. | bovine, ovine, and caprine milk fats were treated with pregastric lipases (kid goat, calf, and lamb), microbial lipases (candida cylindracea, c. cylindracea ay30, aspergillus niger apf12, rhizopus arrhizus, penicillium roqueforti r10, and mucor zavanicus map 10), porcine pancreatic lipase, or milk lipase. all three pregastric lipases preferentially hydrolyzed volatile branched-chain and short n-chain fatty acids from each milk fat. pregastric lipases also released a relatively low proportion of ... | 1993 | 8463483 |
| [placental aspergillosis: myth or reality? apropos of a case with fetal death in utero]. | the authors report an original case-history of massive aspergillosis of the placenta that occurred in a 24 year old primigravida who had had no previous history or clinical changes in pregnancy. it caused fetal death in utero with retention and maceration of the fetus. macroscopic examination showed that the left lip was cleft and that the placenta was studded with isolated confluent diffuse whitish granulations. histologic examination made us think that these appearances were those of aspergill ... | 1993 | 8463573 |
| microbial reduction of aromatic carboxylic acids. | several benzoic, cinnamic and phenylacetic acid derivatives were screened with 20 micro-organisms, mainly fungi, for the reduction of their carboxylic function. for all organisms several compounds were reduced in fairly good yields up to 80% to the corresponding alcohol. no general rule could be established, concerning the substitution pattern, as to which compounds were transformed to the alcohol. generally the reactions were accomplished within 48-70 h. only minor, if any, side products were d ... | 1993 | 8471102 |
| subsite affinities of aspergillus niger glucoamylase ii determined with p-nitrophenylmaltooligosaccharides. | kinetic parameters were obtained for glucoamylase catalysed hydrolysis of substrates of an alpha-(1,4)-maltooligosaccharide series and of a p-nitro-phenyl-alpha-maltooligosaccharide series. p-nitrophenyl substrates of chain length 11 and 17 were synthesized in 97% and 95% purity, respectively, to test the significance of binding at remote subsites. the affinities of the subsites > 4 are demonstrated to be insignificant. the subsite binding contributions for d-glucopyranosyl and for p-nitrophenyl ... | 1993 | 8471180 |
| a truncated glucoamylase gene fusion for heterologous protein secretion from aspergillus niger. | the secreted yield of hen egg-white lysozyme (hewl) from the filamentous fungus aspergillus niger was increased 10-20-fold by constructing a novel gene fusion. the cdna sequence encoding mature hewl was fused in frame to part of the native a. niger gene encoding glucoamylase (glaa), separated by a proteolytic cleavage site for in vivo processing. using this construct, peak secreted hewl yields of 1 g/l were obtained in a. niger shake flask cultures compared to about 50 mg/l when using an express ... | 1993 | 8472909 |
| comparison of several new chromogenic galactosides as substrates for various beta-d-galactosidases. | the kinetic characteristics of beta-galactosidases from bovine liver and testes, escherichia coli, aspergillus niger and jack bean were studied using five newly-developed colorimetric substrates. all the chromophores released by enzyme hydrolysis had high extinction coefficients in the visible region of the spectrum. varying amounts of substrate inhibition were found with each of these substrates (vbztm-gal, vlm-gal, vlpr-gal, vqm-gal and vqpr-gal), but this was not a significant problem if the ... | 1993 | 8476929 |
| mycoflora and mycotoxin of hazelnut (corylus avellana l.) and walnut (juglans regia l.) seeds in egypt. | fifty-one species and 3 varieties appertaining to 20 genera were collected from 20 samples of each of hazelnut and walnut seeds on glucose- and 40% (w/v) sucrose-czapek's agar at 25 degrees c and 45 degrees c with the most common mesophiles were aspergillus flavus, a. fumigatus, a. niger, cladosporium cladosporioides, c. herbarum, penicillium chrysogenum, p. citrinum and p. oxalicum. fusarium (represented by f. equiseti, f. moniliforme and f. oxysporum) was recovered from walnut seeds in moderat ... | 1993 | 8480455 |
| production of high concentrations of ethanol from inulin by simultaneous saccharification and fermentation using aspergillus niger and saccharomyces cerevisiae. | pure nonhydrolyzed inulin was directly converted to ethanol in a simultaneous saccharification and fermentation process. an inulinase-hyperproducing mutant, aspergillus niger 817, was grown in a submerged culture at 30 degrees c for 5 days. the inulin-digestive liquid culture (150 ml) was supplemented with 45 g of inulin, 0.45 g of (nh4)2so4, and 0.15 g of kh2po4. the medium (ph 5.0) was inoculated with an ethanol-tolerant strain, saccharomyces cerevisiae 1200, and fermentation was conducted at ... | 1993 | 8481000 |
| topical treatment of pulmonary aspergilloma by antifungals. relationship between duration of the disease and efficacy of therapy. | twelve patients with aspergilloma were treated with intracavitary or endobronchial administration of antifungals. patients with successful therapy had significantly shorter mean duration of the disease course (3.6 months) than the less effective group (44.4 months, p < 0.01). minimal inhibitory concentrations of antifungal agents against isolated strains of aspergilli were considerably lower than estimated intracavitary concentrations of the antifungals. a pathologic examination suggested that t ... | 1993 | 8486021 |
| antimicrobial activity determined in strains of bacillus circulans cluster. | wild-type strains of the genus bacillus were screened for antimicrobial activity. two strains exhibited antimicrobial activity against micrococcus luteus and were identified as bacillus polymyxa mir-23 and bacillus circulans mir-13. bacillus polymyxa mir-23 was active against escherichia coli, pseudomonas aeruginosa and aspergillus niger, whereas bacillus circulans mir-13 did not show activity against these microorganisms. bacillus subtilis atcc 6633 and b. polymyxa atcc 10401 were used as stand ... | 1993 | 8500778 |
| production, purification and characterization of the catalytic domain of glucoamylase from aspergillus niger. | the catalytic domain of glucoamylases g1 and g2 from aspergillus niger is produced in vitro in high yield by limited proteolysis using either subtilisin novo or subtilisin carlsberg. purification by affinity chromatography on an acarbose-sepharose column followed by ion-exchange chromatography on hiload q-sepharose leads to separation of a number of structurally closely related forms of domain. the cleavage occurs primarily between val-470 and ala-471 as indicated by c-terminal sequencing, where ... | 1993 | 8503847 |
| effect of processing on the mycoflora and aflatoxin b1 level of a cassava-based product. | cassava bread was prepared by pre-gelling, battering and baking cassava flour to which were added, in moderate amounts, sugar, yeast solution and edible oil. baking was at 215 degrees c for 40 min. no mould was isolated from the cassava bread and the mean value of aflatoxin b1 (afb1) for the three subsamples of cassava bread was 0.03 microgram/kg. the cassava tuber (manihot esculenta crantz), which was used for the production of cassava bread had an initial afb1 level of 1.91 micrograms/kg and t ... | 1993 | 8506233 |
| glucoamylase overexpression in aspergillus niger: molecular genetic analysis of strains containing multiple copies of the glaa gene. | a strategy, based on the usage of the amds selection marker and a cosmid vector containing four copies of the glucoamylase gene (glaa), was developed to obtain glucoamylase (gla)-overproducing a. niger strains. with this strategy, fungal strains carrying up to 200 copies of the glaa gene could be isolated at a relatively high frequency. in each transformant analysed, integration occurred in a single chromosome. a significant increase in the extracellular gla production was observed in most of th ... | 1993 | 8513339 |
| purification, characterization, and lytic activity against naegleria fowleri of two amoebicins produced by bacillus licheniformis a12. | bacillus licheniformis a12 produces two amoebolytic substances (amoebicins a12-a and a12-b) in liquid media during sporulation. both substances have been purified and characterized. they are heat- and protease-resistant peptides containing aspartic acid, glutamic acid, serine, proline, and tyrosine in a molar ratio of 5:2:2:2:2. no fatty acids or carbohydrates have been detected. their molecular weight is 1,430. purified amoebicins a12-a and a12-b exhibit amoebolytic action against naegleria fow ... | 1993 | 8517742 |
| synthesis of 2-deoxy-glucooligosaccharides through condensation of 2-deoxy-d-glucose by glucoamylase and alpha-glucosidase. | glucoamylases from aspergillus niger and rhizopus niveus catalyzed condensation of 2-deoxy-d-glucose (dglc) to yield deoxy-glucooligosaccharides with polymerization degrees of 2-5. the enzymes also gave a small amount of products from 3-deoxy-d-glucose, but no products from 6-deoxy-d-glucose. a. niger alpha-glucosidase also catalyzed condensation of dglc, while torula and saccharomyces alpha-glucosidases had low activity. alpha-1,4-, 1,6-, and 1,3-linked deoxy-glucobioses were isolated and ident ... | 1995 | 8520115 |
| purification and properties of endo-beta-1,4-d-galactanase from aspergillus niger. | an endo-beta-1,4-d-galactanase was purified 1735-fold from a commercial enzyme preparation of aspergillus niger. the endogalactanase was homogeneous by sds-page, having an apparent molecular weight of 32,000. it specifically hydrolyzed beta-1,4-d-galactan, and is shown to be capable of releasing galactosyl oligomers and galactose from the soybean pectic polysaccharides. | 1995 | 8520117 |
| the nitrate reductase gene from a shoyu koji mold, aspergillus oryzae kbn616. | a niad gene encoding nitrate reductase was isolated from aspergillus oryzae kbn616 and sequenced. the structural gene comprises 2973 bp and 868 amino acids, which showed a high degree of similarity to nitrate reductases from other filamentous fungi. the coding sequence is interrupted by six introns varying in size from 48 to 98 bp. the intron positions are all conserved among the niad genes from a. oryzae, aspergillus nidulans, and aspergillus niger. a homologous transformation system was develo ... | 1995 | 8520125 |
| cre1, the carbon catabolite repressor protein from trichoderma reesei. | in order to investigate the mechanism of carbon catabolite repression in the industrially important fungus trichoderma reesei, degenerated pcr-primers were designed to amplify a 0.7-bp fragment of the cre1 gene, which was used to clone the entire gene. it encodes a 402-amino acid protein with a calculated m(r) of 43.6 kda. its aa-sequence shows 55.6% and 54.7% overall similarity to the corresponding genes of aspergillus nidulans and a. niger, respectively. similarity was restricted to the aa-reg ... | 1995 | 8521952 |
| [effect of a supplemental aspergillus niger phytase on the utilization of plant phosphorus by rainbow trout (oncorhynchus mykiss)]. | effects of a supplemental aspergillus niger-phytase on digestibility and utilization of dietary phosphorus (p) were studied in three experiments with rainbow trout. p concentration in the diets was 4.8 and 5.8 g/kg dm, respectively. the p contained in the diet originated solely from plants, mainly soy-products. digestibility of p was studied using the stripping method and hydrochloride insoluble ash as marker. utilization was studied in growth trials by use of the comparative body analysis. at a ... | 1995 | 8526727 |
| purification and characterization of a novel adp-dependent glucokinase from the hyperthermophilic archaeon pyrococcus furiosus. | pyrococcus furiosus uses a modified embden-meyerhof pathway during growth on poly- or disaccharides. instead of the usual atp-dependent glucokinase, this pathway involves a novel adp-dependent (amp-forming) glucokinase. the level of this enzyme and some other glycolytic enzymes appeared to be closely regulated by the substrate. growth on cellobiose resulted in a high specific activity of 0.96 units mg-1, whereas on pyruvate a 10-fold lower activity was found. the adp-dependent glucokinase was pu ... | 1995 | 8530474 |
| identification and elimination by site-directed mutagenesis of thermolabile aspartyl bonds in aspergillus awamori glucoamylase. | both native aspergillus niger glucoamylase and wild-type aspergillus awamori glucoamylase expressed in saccharomyces cerevisiae, which have identical primary structures, undergo hydrolysis at aspartyl bonds at low ph values and elevated temperatures. in native a.niger enzyme the asp126-gly127 bond was preferentially cleaved at ph 3.5, while at ph 4.5 cleavage of the asp257-pro258 and asp293-gly294 bonds was dominant. in wild-type a.awamori glucoamylase, cleavage of the latter was dominant at bot ... | 1995 | 8532682 |
| half-site reactivity with p-nitrophenylhydrazine and subunit separation of the dimeric copper-containing amine oxidase from aspergillus niger. | structural properties of dimeric (2 x 75 kda) copper-containing amine oxidase (ec 1.4.3.6) from aspergillus niger were studied. the enzyme treated with sds was dissociated into subunits which showed different mobility on polyacrylamide gel without sds. the separated subunits had no activity but a quinone moiety was detected in both by a redox-cyclic quinone staining. after titration of the enzyme with p-nitrophenylhydrazine, which showed half-site reactivity (1 mole per dimer), and sds treatment ... | 1995 | 8535292 |
| stable accumulation of aspergillus niger phytase in transgenic tobacco leaves. | phytase from aspergillus niger increases the availability of phosphorus from feed for monogastric animals by releasing phosphate from the substrate phytic acid. a phytase cdna was constitutively expressed in transgenic tobacco (nicotiana tabacum) plants. secretion of the protein to the extracellular fluid was established by use of the signal sequence from the tobacco pathogen-related protein s. the specific phytase activity in isolated extracellular fluid was found to be approximately 90-fold hi ... | 1995 | 8539288 |
| aspergillus niger var. macrosporus proteinase b. cdna cloning, expression, and activation of the proenzyme. | | 1995 | 8540377 |
| expression and secretion of recombinant aspartic proteinases by bacillus brevis. | | 1995 | 8540378 |
| expression in e. coli of aspergillus niger var. macrosporus proteinase a, a non-pepsin type acid proteinase. | | 1995 | 8540379 |
| x-ray crystallographic study of a non-pepsin-type acid proteinase, aspergillus niger proteinase a. | | 1995 | 8540380 |
| conformation analysis of non-pepsin-type acid proteinase a from the fungus aspergillus niger by nmr. | | 1995 | 8540381 |
| analysis of the regulation of the aspergillus nidulans penicillin biosynthesis gene aat (pende), which encodes acyl coenzyme a:6-aminopenicillanic acid acyltransferase. | the regulation of the aspergillus nidulans penicillin biosynthesis gene aat (pende), which encodes acyl coenzyme a:6-aminopenicillanic acid acyltransferase (aat), was analysed. major transcriptional start sites map within 100 nucleotides upstream from the aat initiation codon. to study the regulation of aat expression, various aat-lacz gene fusions were constructed, in which the aat promoter region was fused in frame with the escherichia coli lacz reporter gene. a. nidulans strains carrying reco ... | 1995 | 8544821 |
| phytase from aspergillus niger. | 132 microorganisms, isolates from soil and decayed fruits, were tested for phytase production. all isolates intensively producing active extracellular phytase were of fungal origin. the most active fungal isolates with phytase activity were identified as aspergillus niger. at the end of the growth phase, the extracellular phytase activity produced by a. niger strain 92 was 132 nkat/ml, with strain 89 it was 53 nkat/ml. in both strains the extracellular enzyme activity exhibited two marked activi ... | 1994 | 8549996 |
| the isolation of ant1, a transposable element from aspergillus niger. | a transposable element has been isolated from the industrially important fungus aspergillus niger (strain n402). the element was identified as an insertion sequence within the coding region of the nitrate reductase gene. it had inserted at a ta site and appeared to have duplicated the target site upon insertion. the isolated element was found to be 4798 bp in length and contained 37-bp inverted, imperfect, terminal repeats (itrs). the sequence of the central region of the element revealed an ope ... | 1995 | 8552048 |
| chemoenzymatic synthesis of 6 omega-s-alpha-d-glucopyranosyl-6 omega-thiomaltooligosaccharides: their binding to aspergillus niger glucoamylase g1 and its starch-binding domain. | a coupling reaction of cyclodextrin glucosyltransferase (cgtase) with glucose and 6-deoxy-6-iodo-cyclomaltoheptaose (1), in the presence of glucoamylase, followed by acetylation, led to a convenient synthesis of acetylated 6iii-deoxy-6iii-iodo-maltotriose (2) and 6iv-deoxy-6iv-iodomaltotraose (3). nucleophilic displacement of the iodine atom of these protected maltotriose and maltotetraose analogs by the activated form of 2,3,4,6-tetra-o-acetyl-1-s- acetyl-1-thio-alpha-d-glucose (4) afforded per ... | 1995 | 8556738 |
| production of feruloyl/rho-coumaroyl esterase activity by penicillium expansum, penicillium brevicompactum and aspergillus niger. | extracellular esterase production by penicillium expansum, penicillium brevicompactum and aspergillus niger was determined in both liquid and solid-state culture. methyl ferulate was used as the main carbon source in liquid culture whereas wheat bran and sugar beet pulp were used in solid-state culture. extracted enzyme for each fungus showed activity in the presence of onp butyrate, methyl ferulate, methyl coumarate and two 'natural' feruloylated carbohydrate esters. higher enzyme recoveries we ... | 1995 | 8557619 |
| utilization of water hyacinth cellulose for production of cellobiase-rich preparation by aspergillus niger 1. | production of a cellobiase-rich preparation by aspergillus niger 1 was achieved using water hyacinth cellulose as the sole carbon source in the culture medium. production of cellobiase, carboxymethylcellulase (cmc-ase) and filter paper (fp)-cellulase was favoured by controlling the ph of the culture medium during fermentation at 5.0. sodium citrate (0.5%), sodium phytate (0.1%), tween-80 (0.2%, v/v) and asparagine (0.07%) had stimulating effects on the productivity of cellobiase, cmc-ase and fp- ... | 1995 | 8559082 |
| glucose oxidase mediation by soluble and immobilized electroactive detergents. | a series of novel, surface-active, inorganometallic complexes of osmium were synthesized and then characterized (using electrochemical techniques) as electron transfer mediators for glucose oxidase (ec 1.1.3.4, god) from aspergillus niger. the mediators contain a dipyridylamine ligand bearing (on the amine nitrogen) a saturated alkyl chain (typically c5 to c12), omega-terminated with either a methyl group or a functional group such as carboxyl or hydroxyl. such compounds displayed subtle differe ... | 1996 | 8562011 |
| evaluating the preservative effectiveness of rgp lens care solutions. | we examined the antimicrobial preservative efficacy of nine rigid gas permeable (rgp) contact lens care solutions by challenging them in a laboratory study with both standard test organisms and preservative-resistant strains. solutions containing polyhexamethylene biguanide (phmb), such as boston advance (15 ppm) and a boston advance enhanced comfort formula (5 ppm phmb + 30 ppm chlorhexidine gluconate [chg]) were most effective at rapidly killing vegetative cells, killing all bacteria and yeast ... | 1995 | 8565192 |
| nucleotide sequence of the aspergillus niger srpa gene. | the aspergillus niger (an) gene srpa, encoding a protein with homology to the signal recognition particle (srp) 54-kda protein from saccharomyces cerevisiae (sc), has been isolated and the nucleotide sequence determined. the putative an srpa gene is comprised of two exons of 78 and 1527 bp separated by a 49-bp intron, and encodes a protein of 534 amino acids that is 53% identical to sc srp54. | 1995 | 8566805 |
| cloning and characterisation of genes (pkc1 and pkca) encoding protein kinase c homologues from trichoderma reesei and aspergillus niger. | oligonucleotides, designed on the basis of conserved flanking amino acid sequence segments within the catalytic domain of eukaryotic protein kinase c (pkc) proteins, were used as primers for polymerase chain reactions to amplify a 427-bp chromosomal dna fragment from the filamentous fungus trichoderma reesei. this fragment was then used to isolate genes encoding pkc homologues of t. reesei and aspergillus niger (pkc1 and pkca, respectively). the genes contain six (t. reesei) and eight (a. niger) ... | 1996 | 8569684 |
| [a case of bronchial asthma complicated by mycosis]. | | 1995 | 8571247 |
| purification and characterization of copper-metallothionein from aspergillus niger by affinity chromatography. | biomass of aspergillus niger was obtained from a microbial culture and a copper (cu) induction was performed after 72 h of fermentation. the crude induced metallothionein extract was obtained by cell disruption and partly purified by a heat treatment and ultrafiltration. the purification of metallothionein by affinity chromatography resulted in three major fractions: fiva, fivb and fivc3. cu analysis demonstrated that only fraction fivc contained the cu-metallothionein. spectrophotometric analys ... | 1995 | 8573292 |
| integrative and replicative transformation of penicillium canescens with a heterologous nitrate-reductase gene. | a wild isolate of penicillium canescens was subjected to mutagenesis, and 150 chlorate-resistant mutants were isolated and classified in respect of their ability to utilize various nitrogen sources. strains supposedly deficient in nitrate reductase have been transformed with the nitrate-reductase gene from aspergillus niger. transformation probably occurred by non-homologous integration of the transforming vector into the chromosome. co-transformation with the ama 1 replicating element from a. n ... | 1995 | 8575022 |
| molecular probes for diagnosis of fungal infections. | we have developed 21 specific nucleic acid probes which target the large subunit rrna genes from aspergillus flavus, aspergillus fumigatus, aspergillus glaucus, aspergillus niger, aspergillus terreus, blastomyces dermatitidis, candida albicans, candida (torulopsis) glabrata, candida guilliermondii, candida kefyr, candida krusei, candida lusitaniae, candida parapsilosis, candida tropicalis, coccidioides immitis, cryptococcus neoformans var. gattii, cryptococcus neoformans var. neoformans, filobas ... | 1995 | 8576345 |
| efficient expression and secretion of aspergillus niger rh5344 polygalacturonase in saccharomyces cerevisiae. | an aspergillus niger endopolygalacturonase (ec 3.2.1.15) cdna was expressed in the yeast saccharomyces cerevisiae. secretion of the protein into the growth medium was efficiently directed by the fungal leader sequence, and processing occurred at the same site as in aspergillus. the expression level was significantly enhanced by using a "short" version of the yeast adhi promoter. an additional increase in the yield of heterologous protein was due to a higher plasmid stability and a rise in plasmi ... | 1995 | 8579828 |
| heterologous protein secretion by aspergillus niger growing in submerged culture as dispersed or aggregated mycelia. | the secreted production of a heterologous enzyme, hen egg-white lysozyme, by aspergillus niger was studied in shake flasks containing media of different initial viscosities. raising the viscosity of the medium by addition of polyvinylpyrrolidone (pvp) brought about a transition in the form of growth from aggregated mycelia (pellets) to dispersed mycelia. the specific yield of lysozyme in cultures containing an initial concentration of 5% (w/v) starch was 8 mg lysozyme/g dry weight. addition of 2 ... | 1995 | 8579829 |
| comparative effects of gamma and microwave irradiation on the quality of black pepper. | powdered black pepper from egyptian markets, was irradiated with different recommended doses of gamma rays (5.0 and 10.0 kgy) and with microwaves for different periods (20, 40 and 75 s) to improve its hygienic quality. the most common bacterial isolates were of three genera bacillus, clostridium and micrococcus (7.5 x 10(6)), whereas the predominant fungi (7.8 x 10(4)) were aspergillus species, a. glaucus, a. flavus, a. niger and a. ochraceus. doses of gamma irradiation used (5.0 and 10 kgy) wer ... | 1995 | 8585332 |
| aspergillus culture filtrates and sputum sols from patients with pulmonary aspergillosis cause damage to human respiratory ciliated epithelium in vitro. | aspergillus species frequently colonize lower respiratory tracts and lungs with localized underlying conditions (healed tuberculous cavity, cystic fibrosis, bronchiectasis, etc.) even in subjects without systemic predisposing factors. we investigated the in vitro effects of culture filtrates of aspergillus species and sputum sols from patients with pulmonary aspergillosis on ciliary beat frequency (cbf) and epithelial integrity of human respiratory ciliated epithelium. culture filtrates of 25 cl ... | 1995 | 8586122 |
| differential scanning calorimetric studies on the domain structure of aspergillus glucoamylase. | thermal unfolding of two forms of aspergillus niger glucoamylase was observed by adiabatic differential scanning calorimetry (dsc) at ph 7. the dsc traces of the larger form of the enzyme, g1, and the shorter form which lacks the c-terminal starch-binding domain of g1, g2, could be resolved by assuming two-state unfolding of five and four independent components, respectively. the thermal unfolding of the starch-binding domain was found to be reversible, but that of the catalytic domain was irrev ... | 1995 | 8586614 |
| the alpha-d-mannan core of a complex cell-wall heteroglycan of trichoderma reesei is responsible for beta-glucosidase activation. | a heteroglycan responsible for the binding of the enzyme beta-1,4-d-glucosidase (ec 3.2.1.21) to fungal cell walls was isolated from cell walls of the filamentous fungus trichoderma reesei. the heteroglycan, composed of mannose, galactose, glucose, and glucuronic acid, also activated beta-1,4-d-glucosidase, beta-1,4-d-xylosidase and n-acetyl-beta-1,4-d-glucosaminidase activity in vitro. the structural backbone of this heteroglycan was prepared by acid hydrolysis and gel filtration. the molecular ... | 1995 | 8588743 |
| new protease mutants in aspergillus niger result in strongly reduced in vitro degradation of target proteins; genetical and biochemical characterization of seven complementation groups. | several mutants of aspergillus niger, deficient in extracellular protease expression, have been isolated and characterized both genetically and biochemically. the mutant strains, obtained after in vivo uv-mutagenesis of conidiospores and selected by haloscreening on a new dual-substrate plate assay, belong to at least seven different complementation groups. these seven prt loci were assigned to linkage groups using master strains with marked chromosomes. one prt locus (prtc) could be assigned to ... | 1995 | 8590475 |
| release of ferulic acid from wheat bran by a ferulic acid esterase (fae-iii) from aspergillus niger. | ferulic acid was efficiently released from a wheat bran preparation by a ferulic acid esterase from aspergillus niger (fae-iii) when incubated together with a trichoderma viride xylanase (a maximum of 95% total ferulic acid released after 5 h incubation). fae-iii by itself could release ferulic acid but at a level almost 24-fold lower than that obtained in the presence of the xylanase (2 u). release of ferulic acid was proportional to the fae-iii concentration between 0.1 u and 1.3 u, but the pr ... | 1995 | 8590660 |
| optimization of glucose oxidase production by aspergillus niger using genetic- and process-engineering techniques. | wild-type aspergillus niger nrrl-3 was transformed with multiple copies of the glucose oxidase structural gene (god). the gene was placed under the control of the gpda promoter of a. nidulans. for more efficient secretion the alpha-amylase signal peptide from a. oryzae was inserted in front of god. compared to the wild type, the recombinant strain nrrl-3 (god3-18) produced up to four times more extracellular glucose oxidase under identical culture conditions. addition of yeast extract (2 gl-1) t ... | 1995 | 8590664 |
| polyol pools in aspergillus niger. | the accumulation and excretion of polyols was investigated under various growth conditions and at different stages of the life cycle of aspergillus niger. glycerol was found to be the major solute in osmotic adjustment of the hyphae. conidiospores contain large amounts of mannitol, which are rapidly metabolized during early germination, leading to the accumulation of glycerol. glycerol is the major polyol in young mycelium, whereas in older mycelium mannitol and erythritol predominate. in all ex ... | 1995 | 8593956 |
| cloning of corticium rolfsii glucoamylase cdna and its expression in saccharomyces cerevisiae. | a cdna coding for the glucoamylase of corticium rolfsii ahu 9627 was cloned using synthetic oligonucleotide probes that code for inner amino acid sequences of the purified enzyme. this clone (cg 15) is 1900 base pairs long and contains the entire coding region for a polypeptide of 579 residues. comparison with amino acid sequences of other fungal glucoamylases showed homologies of 35%-56%, and most homology with that of aspergillus niger. the expression plasmid pacg 115 was constructed by introd ... | 1995 | 8597548 |
| inhibition of copper/quinoprotein amine oxidases from aspergillus niger by benzophenanthridine alkaloids. | inhibition of copper/quinoprotein amine oxidases (ec 1.4.3.6), ao-i (dimer 2 x 75 kda) and ao-ii (monomer 80 kda), from the fungus aspergillus niger by benzophenanthridine alkaloids sanguinarine, chelerythrine, and fagaronine were studied. for both amine oxidases the alkaloids showed reversible noncompetitive inhibition of n-hexylamine oxidation with ki 0.6, 0.9 and 2.8 mm for sanguinarine, chelerythrine, and fagaronine, respectively. the values of the inhibition constants corresponded to pkr+ v ... | 1995 | 8598539 |
| identification, cloning and analysis of the aspergillus niger gene pacc, a wide domain regulatory gene responsive to ambient ph. | a wide domain regulatory gene implicated in modulating gene expression in response to ambient ph has been cloned and sequenced from the industrially useful filamentous fungus aspergillus niger. this gene, pacc, is able to restore a pacc+ phenotype to a. nidulans paccc11 and paccc14 mutants with respect to extent of conidiation, conidial pigment intensity and acid phosphatase regulation. the pacc gene of a. niger comprises three exons, encodes a three-zinc-finger protein of 677 amino acids, and s ... | 1996 | 8602152 |
| inversion of configuration during hydrolysis of alpha-1,4-galacturonidic linkage by three aspergillus polygalacturonases. | endopolygalacturonases i and ii (pgi and pgii) of aspergillus niger and an exopolygalacturonase (exopg) of a. tubingensis were investigated to reveal the stereochemistry of their hydrolytic action. reduced pentagalacturonic acid (pentagalu-ol) and reduced trigalacturonic acid (trigalu-ol) were used as non-reducing substrates for the enzymes. the configuration of the reducing ends in the products formed in d2o reaction mixtures was followed by 1h-nmr spectroscopy. it has been unambiguously establ ... | 1996 | 8605979 |
| unusual antimicrobial compounds from aeollanthus buchnerianus. | using bioassay guided isolation, three novel 12 carbon polyoxygenated fatty acids and a novel abietane diterpene have been isolated from the chloroform extract of aerial parts of aeollanthus buchnerianus (lamiaceae). rigorous spectroscopic methods were used for compound identification. (z,z)-8zeta-acetoxy-5zeta-hydroxydodeca-2,6-dienoic acid and (z,z)-5zeta, 8zeta-dihydroxydodeca-2,6-dienoic acid inhibited the spore germination of cladosporium cucumerinum (both with minimum inhibitory dose (mid) ... | 1996 | 8608820 |