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reduction of flatus-inducing factors in soymilk by immobilized alpha-galactosidase.alpha-galactosidase from aspergillus oryzae was immobilized on chitosan beads using glutaraldehyde as a cross-linking agent. the general properties of free and immobilized enzymes were determined. the optimum ph for the free and immobilized enzymes was 4.8 and 4.6 respectively. the optimum temperature for the free enzyme was 50 degrees c, whereas that of immobilized enzyme was increased to 56 degrees c. kinetic parameters were determined with synthetic substrate (p-nitrophenyl alpha-d-galactopyr ...200616780418
production of high-content galacto-oligosaccharide by enzyme catalysis and fermentation with kluyveromyces marxianus.of three beta-galactosidases from aspergillus oryzae, kluyveromyces lactis and bacillus sp., used for the production of low-content galacto- oligosaccharides (gos) from lactose, the latter produced the highest yield of trisaccharides and tetrasaccharides. gos production was enhanced by mixing beta-galactosidase glucose oxidase. the low-content gos syrups, produced either by beta-galactosidase alone or by the mixed enzyme system, were subjected to the fermentation by kluyveromyces marxianus, wher ...200616786243
impact of fermented brown rice with aspergillus oryzae intake and concentrations of organochlorine pesticides in blood of humans from japan. 200616786444
optimization of multienzyme production by two mixed strains in solid-state fermentation.f(3) and f(4) strains of aspergillus niger were screened from five strains of fungi to produce multienzyme preparations (containing cellulase, hemicellulase, glucoamylase, pectinase, and acidic proteinase) as dietary supplementation. enzyme activities indicated that 1:4 (f(3) to f(4)) was the optimum mixture proportion, and 0.3% (w/w) was the preferable pitching rate. in bran mash containing 54.5% (w/w) water, f(3) and f(4) could produce the supplementation better when cultured 30 to 36 h at 30 ...200616802152
proteomic methods applied to the analysis of immobilized biocatalysts.methods adapted from proteomics can directly characterize proteins present in immobilized biocatalysts. complete hydrolysis followed by hplc analysis of tyr and phe estimates total protein bound, and is preferable to conventional difference methods, as tested with subtilisin carlsberg on silica. this new method shows that various treatments give quantitative desorption of proteins immobilized by adsorption. intact desorbed proteins may be analyzed by electrospray mass spectrometry. the candida a ...200616807923
discovery, cloning and heterologous expression of secreted potato proteins reveal erroneous pre-mrna splicing in aspergillus oryzae.a novel transposon assisted signal trapping (tast) technology, developed to specifically select only the secreted proteins, was used to discover novel extracellular plant proteins from solarium tuberosum infected with phytophthora infestans. analysis of 384 hits provided 191 p. infestans and s. tuberosum sequences of secreted proteins, with an approx. 2/3 of these originating from potato. subsequent screening for interesting genes was carried out using bioinformatics. a selected variety of the d ...200616814894
rate of iodine volatilization and accumulation by filamentous fungi through laboratory cultures.five strains of basidiomycetes (lentinula edodes, coprinus phlyctidosporus, hebeloma vinosophyllum, pleurotus ostreatus and agaricus bisporus), one strain of ascomycete (hormoconis resinae) and six strains of imperfect fungi (penicillium chrysogenum, penicillium roquefortii, cladosporium cladosporioides, alternaria alternata, aspergillus niger and aspergillus oryzae) were cultured in a liquid medium containing a radioactive iodine tracer ((125)i), and were tested for their abilities to volatiliz ...200616828143
thermostability of native and pegylated myceliophthora thermophila laccase in aqueous and mixed solvents.a commercial preparation of laccase (ec 1.10.3.2), cloned from myceliophthora thermophila and expressed in aspergillus oryzae (mtl), was purified and modified by conjugation with poly(ethylene glycol) (m(r) = 5000) and is labeled peg-mtl. native enzyme was found to have a molecular mass of 80 kda, as determined by gel filtration, and 110 kda, by sds-page. the oxidative dimerization of 2,6-dimethoxyphenol (dmp) to produce the corresponding dibenzoquinone was catalyzed by mtl in a manner comparabl ...200616848420
aovps24, a homologue of vps24, is required for vacuolar formation which could maintain proper growth and development in the filamentous fungus aspergillus oryzae.vps24 (vacuolar protein sorting) is a component of escrt iii (endosomal sorting complex required for transport), which is required for the formation of mvb (multivesicular body). we have isolated the vps24 homologue gene, aovps24, from the filamentous fungus aspergillus oryzae, and analyzed the localization of aovps24 using egfp. aovps24 was localized in the cytoplasm and late endosome-like structures. furthermore, we constructed an aovps24 disruptant, which showed impaired growth, conidiation, ...200616857172
an efficient two step purification and molecular characterization of beta-galactosidases from aspergillus oryzae.beta-galactosidases (beta-d-galactoside-galactohydrolases (ec 3.2.1.23), lactases) are important industrial enzymes used for the hydrolysis of lactose from milk and milk whey. these enzymes are produced by different organisms and purified by multi-step procedures. the multi-step purification schemes are cost and time ineffective which can also lead to poor yield, denaturation and loss of enzymatic activity. in our study, extracellular beta-galactosidase from mutant strain aspergillus oryzaeh26-1 ...200616865665
possible involvement of pleiomorphic vacuolar networks in nutrient recycling in filamentous fungi.morphological analyses of vacuoles in filamentous fungi in the past decade have led to the remarkable finding that they are highly pleiomorphic organelles. among them, tubular vacuoles have been implicated in nutrient transport between hyphal tips and the host plant surface in mycorrhizal fungi. however, a series of works suggested the presence of tubular vacuoles in other fungi that are not mycorrhizal, including aspergillus oryzae, hinting at more general roles of the tubular vacuoles. recentl ...200616874107
development of a versatile expression plasmid construction system for aspergillus oryzae and its application to visualization of mitochondria.we report here a development of the multisite gateway(tm)-based versatile plasmid construction system applicable for the rapid and efficient preparation of aspergillus oryzae expression plasmids. this system allows the simultaneous connection of the three dna fragments inserted in entry clones along with a destination vector in a defined order and orientation. we prepared a variety of entry clones and destination vectors containing promoters, genes encoding carrier-proteins and fusion tags, and ...200616880596
functional analysis of the atg8 homologue aoatg8 and role of autophagy in differentiation and germination in aspergillus oryzae.autophagy is a well-known degradation system, induced by nutrient starvation, in which cytoplasmic components and organelles are digested via vacuoles/lysosomes. recently, it was reported that autophagy is involved in the turnover of cellular components, development, differentiation, immune responses, protection against pathogens, and cell death. in this study, we isolated the atg8 gene homologue aoatg8 from the filamentous fungus aspergillus oryzae and visualized autophagy by the expression of ...200616896216
expression of aspergillus oryzae phytase gene in aspergillus oryzae rib40 niad(-).aspergillus oryzae rib40 niad(-) was transformed using a plasmid constructed with the a. oryzae phytase gene and pnan8142 vector. the culture broth of the transformant, which was grown in a medium containing starch as a carbon source and polyvinylpyrrolidone showed phytase activity of a maximum of 2.0 units ml(-1) at 37 degrees c, ph 5.5.200617270723
high-throughput genotyping of filamentous fungus aspergillus oryzae based on colony direct polymerase chain reaction.high-throughput genotyping of aspergillus oryzae was achieved using an fta card for the extraction of a genomic dna template for polymerase chain reaction from a fungal colony growing on an agar plate. this method was then applied to detect other fungal species from agar slants and food materials. this method offers a convenient tool for the genotyping of filamentous fungi without using an organic solvent or specialized equipment.200617270725
identification of genes from aspergillus oryzae that are preferentially expressed in membrane-surface liquid culture.we identified 22 genes from aspergillus oryzae that are preferentially expressed in membrane-surface liquid culture (mslc), among which ser/thr protein kinase (aopk1) and phosphatase (aoppt) genes were cloned. we also revealed that aopk1 encodes a protein with an n-terminal sequence 150 amino acid residues longer than that predicted from the registered sequence in genbank.200617189178
chemical components, palatability, antioxidant activity and antimutagenicity of oncom miso using a mixture of fermented soybeans and okara with neurospora intermedia.the enzyme activities of aspergillus oryzae on koji (malted rice) and neurospora intermedia on s-oncom and o-oncom (fermented soybeans and okara with n. intermedia, respectively) were compared. the major enzymes of n. intermedia were different from those of a. oryzae, and the enzyme activities of o-oncom were extremely higher than those of s-oncom. s5-miso, s10-miso and s9o1-miso replacing 50% or 100% of steamed soybeans with s-oncom or a 9 : 1 mixture of s-oncom and o-oncom, respectively, were ...200616967767
a traditional japanese medicine mitigates tnbs-induced colitis in rats.differences in dietary habits may be one of the reasons that the incidence of inflammatory bowel disease has remained lower in japan than in western countries. we investigated whether a traditional japanese medicine (strong wakamto), based on aspergillus oryzae koji, would exert any effect on experimental colitis in rats.200616990203
innovative effect of illite on improved microbiological conversion of l-tyrosine to 3,4 dihydroxy phenyl l-alanine (l-dopa) by aspergillus oryzae me2 under acidic reaction conditions.in the present investigation, the previous ultraviolet irradiated mutant strain of aspergillus oryzae uv-7 was further improved in terms of 3,4 dihydroxy phenyl l-alanine (l-dopa) activity after chemical mutagenesis through 1-methyl 3-nitro 1-nitroso guanidine (mnng = 250-1500 microg/ml) treatment (0-30 min). among several mutant variants, the one that produced a larger amount of l-dopa from l-tyrosine was designated to as me2 and it was made 2-deoxy-d-glucose-resistant by growing it at various ...200617039388
evaluation of certain food additives.this report represents the conclusions of a joint fao/who expert committee convened to evaluate the safety of various food additives, with a view to recommending acceptable daily intakes (adis) and to prepare specifications for the identity and purity of food additives. the first part of the report contains a general discussion of the principles governing the toxicological evaluation of food additives (including flavouring agents), assessments of intake, and the establishment and revision of spe ...200617069402
in vivo expression of udp-n-acetylglucosamine: alpha-3-d-mannoside beta-1,2-n-acetylglucosaminyltransferase i (gnt-1) in aspergillus oryzae and effects on the sugar chain of alpha-amylase.udp-n-acetylglucosamine: alpha-3-d-mannoside beta-1,2-n-acetylglucosaminyltransferase i (gnt-i) is an essential enzyme in the conversion of high mannose type oligosaccharide to the hybrid or complex type. the full length of the rat gnt-i gene was expressed in the filamentous fungus aspergillus oryzae. a microsomal preparation from a recombinant fungus (strain ng) showed gnt-i activity that transferred n-acetylglucosamine residue to acceptor heptaose, man(5)glcnac(2). the n-linked sugar chain of ...200617090929
olive-mill wastewaters: a promising substrate for microbial lipase production.the present study investigated the valorization of olive-mill wastewater (omw) by its use as a possible growth medium for the microbial production of extra-cellular lipase. to this end, strains of geotrichum candidum (nrrl y-552 and y-553), rhizopus arrhizus (nrrl 2286 and isrim 383), rhizopus oryzae (nrrl 6431), aspergillus oryzae (nrrl 1988 and 495), aspergillus niger (nrrl 334), candida cylindracea (nrrl y-17506) and penicillium citrinum (nrrl 1841 and 3754, isrim 118) were screened. all stra ...200616236495
visualization of the endocytic pathway in the filamentous fungus aspergillus oryzae using an egfp-fused plasma membrane protein.endocytosis is an important process for cellular activities. however, in filamentous fungi, the existence of endocytosis has been so far elusive. in this study, we used aouapc-egfp, the fusion protein of a putative uric acid-xanthine permease with enhanced green fluorescent protein (egfp) in aspergillus oryzae, to examine whether the endocytic process occurs or not. upon the addition of ammonium into the medium the fusion protein was internalized from the plasma membrane. the internalization of ...200616380079
comparison of the aflr gene sequences of strains in aspergillus section flavi.aflatoxins are polyketide-derived secondary metabolites produced by aspergillus parasiticus, aspergillus flavus, aspergillus nomius and a few other species. the toxic effects of aflatoxins have adverse consequences for human health and agricultural economics. the aflr gene, a regulatory gene for aflatoxin biosynthesis, encodes a protein containing a zinc-finger dna-binding motif. although aspergillus oryzae and aspergillus sojae, which are used in fermented foods and in ingredient manufacture, h ...200616385126
molecular analysis of an inactive aflatoxin biosynthesis gene cluster in aspergillus oryzae rib strains.to help assess the potential for aflatoxin production by aspergillus oryzae, the structure of an aflatoxin biosynthesis gene homolog cluster in a. oryzae rib 40 was analyzed. although most genes in the corresponding cluster exhibited from 97 to 99% similarity to those of aspergillus flavus, three genes shared 93% similarity or less. a 257-bp deletion in the aflt region, a frameshift mutation in nora, and a base pair substitution in vera were found in a. oryzae rib 40. in the aflr promoter, two s ...200616391082
identification and analysis of ku70 and ku80 homologs in the koji molds aspergillus sojae and aspergillus oryzae.ku genes play a key role in the non-homologous end-joining pathway. we have identified ku70 and ku80 homologs in the koji molds aspergillus sojae and aspergillus oryzae, and have constructed the disruption mutants of ku70, ku80, and ku70-80 to characterize the phenotypic change in these mutants. neither ku70- nor ku80-disrupted strains show hypersensitivity to the dna damaging agents methylmethane sulfonate (mms) and phleomycin. moreover, undesirable phenotypes, such as poor growth or repressed ...200616428831
cladal relatedness among aspergillus oryzae isolates and aspergillus flavus s and l morphotype isolates.aspergillus flavus is the main etiological agent for aflatoxin contamination of crops. its close relative, a. oryzae, does not produce aflatoxins and has been widely used to produce fermented foods. we compared the phylogeny of a. oryzae isolates and l- and s-type sclerotial isolates of a. flavus using single nucleotide polymorphisms in the omta gene in the aflatoxin biosynthesis gene cluster and deletions in and distal to the norb-cypa intergenic region as phylogenetic signals. aflatoxin-produc ...200616430983
an enzymatically produced novel cyclomaltopentaose cyclized from amylose by an alpha-(1-->6)-linkage, cyclo-{-->6)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->}.a bacterial strain am7, isolated from soil and identified as bacillus circulans, produced two kinds of novel cyclic oligosaccharides. the cyclic oligosaccharides were produced from amylose using a culture supernatant of the strain as the enzyme preparation. the major product was a cyclomaltopentaose cyclized by an alpha-(1-->6)-linkage, cyclo-{-->6)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->4)-alpha-d-glcp-(1-->}. the other minor product was cyclomaltohexao ...200616545346
g-protein and camp-mediated signaling in aspergilli: a genomic perspective.we have carried out an in silico exploration of the genomes of aspergillus nidulans, aspergillus fumigatus, and aspergillus oryzae, and identified components of g-protein/camp-mediated signaling. putative g-protein coupled receptors (gpcrs) were distributed over nine classes. the gpcrs within classes were well conserved among aspergilli but varied in other ascomycetes. as previously observed in a. nidulans and other fungi, three galpha, one gbeta, and one ggamma subunits of g proteins were ident ...200616546420
deletion analysis of the superoxide dismutase (sodm) promoter from aspergillus oryzae.the manganese superoxide dismutase gene (sodm) is very highly expressed in aspergillus oryzae. to elucidate the basis for this high-level expression, deletion analysis of the promoter was undertaken using beta-glucuronidase (gus) as a reporter. deletion of a 63-bp sequence from -200 to -138 in the 1,038-bp sodm promoter caused a drastic decrease in gus activity. in addition, an electrophoretic gel mobility shift assay (emsa) implicated a 30-bp element from -209 to -178 containing cis-element(s) ...200616547700
suppression on the mutagenicity of 4-nitroquinoline-n-oxide by the methanol extracts of soybean koji prepared with various filamentous fungi.in this study, solid fermentation of soybean with various gras filamentous fungi including aspergillus sojae bcrc 30103, aspergillus oryzae bcrc 30222, aspergillus awamori, actinomucor taiwanesis and rhizopus sp. was performed to prepare various soybean kojis. toxicity, mutagenicity and suppression on the mutagenesis induced by a direct mutagen, 4-nitroquinoline-n-oxide (4-nqo) on salmonella typhimurium ta 100, by the various methanol extracts of the prepared soybean koji and unfermented soybean ...200616580082
novel hydrophobic surface binding protein, hsba, produced by aspergillus oryzae.hydrophobic surface binding protein a (hsba) is a secreted protein (14.5 kda) isolated from the culture broth of aspergillus oryzae rib40 grown in a medium containing polybutylene succinate-co-adipate (pbsa) as a sole carbon source. we purified hsba from the culture broth and determined its n-terminal amino acid sequence. we found a dna sequence encoding a protein whose n terminus matched that of purified hsba in the a. ozyzae genomic sequence. we cloned the hsba genomic dna and cdna from a. ory ...200616597938
enhancement of enantioselectivity in the bacillus subtilis protease-catalyzed hydrolysis of n-free amino acid esters using the ester grouping-modification approach.the generality of enantioselectivity enhancement through the modification of the alcohol moiety of a substrate ester was ascertained, for in the bacillus subtilis protease-catalyzed hydrolysis of n-unprotected amino acid esters the enantioselectivity was enhanced largely by switching the conventional methyl ester to esters with a longer alkyl chain such as the isobutyl ester (from e = 3 to e = 130-170 in the case of 4-fluorophenylalanine esters) as in the enzymatic hydrolysis mediated by aspergi ...200616614915
the region in a subunit of the aspergillus ccaat-binding protein similar to the hap4p-recruiting domain of saccharomyces cerevisiae hap5p is not essential for transcriptional enhancement.the ccaat-binding complex in aspergillus species, known as the hap complex, consists of at least three subunits, hapb, hapc, and hape. each hap subunit contains an evolutionarily conserved core domain. in this study, a series of the truncated gene, which encodes the hape subunit of aspergillus oryzae, was constructed to survey the regions essential for the transcriptional enhancement of fungal genes. it was revealed that the non-conserved regions and the conserved region similar to the hap4p rec ...200616636442
lentinula edodes tlg1 encodes a thaumatin-like protein that is involved in lentinan degradation and fruiting body senescence.lentinan is an antitumor product that is purified from fresh lentinula edodes fruiting bodies. it is a cell wall component, comprising beta-1,3-glucan with beta-1,6-linked branches, which becomes degraded during postharvest preservation as a result of increased glucanase activity. in this study, we used n-terminal amino acid sequence to isolate tlg1, a gene encoding a thaumatin-like (tl) protein in l. edodes. the cdna clone was approximately 1.0 kb whereas the genomic sequence was 2.1 kb, and co ...200616648221
substrate specificity of aspergillus oryzae family 3 beta-glucosidase.among glycoside hydrolases, beta-glucosidase plays a unique role in many physiological and biocatalytical processes that involve the beta-linked o-glycosyl bond of various oligomeric saccharides or glycosides. structurally, the enzyme can be grouped into glycoside hydrolase family 1 and 3. although the basic ("retaining, double-displacement") mechanism for the catalysis of family 3 beta-glucosidase has been established, in-depth understanding of its structure-function relationship, particularly ...200616650812
proteomic analysis of extracellular proteins from aspergillus oryzae grown under submerged and solid-state culture conditions.filamentous fungi are widely used for the production of homologous and heterologous proteins. recently, there has been increasing interest in aspergillus oryzae because of its ability to produce heterologous proteins in solid-state culture. to provide an overview of protein secretion by a. oryzae in solid-state culture, we carried out a comparative proteome analysis of extracellular proteins in solid-state and submerged (liquid) cultures. extracellular proteins prepared from both cultures sequen ...200616672490
extracellular production of neoculin, a sweet-tasting heterodimeric protein with taste-modifying activity, by aspergillus oryzae.neoculin (ncl), a protein with sweetness approximately 500-fold that of sugar, can be utilized as a nonglycemic sweetener. it also has taste-modifying activity to convert sourness to sweetness. ncl is a heterodimer composed of an n-glycosylated acidic subunit (nas) and a basic subunit (nbs), which are conjugated by disulfide bonds. for the production of recombinant ncl (rncl) by aspergillus oryzae, alpha-amylase with a kex2 cleavage site, -k-r-, was fused upstream of each of nas and nbs and the ...200616672522
aspergillus oryzae strains with a large deletion of the aflatoxin biosynthetic homologous gene cluster differentiated by chromosomal breakage.recently we divided aspergillus oryzae rib strains into group 1, having seven aflatoxin biosynthesis homologous genes (aflt, nor-1, aflr, nora, avna, verb, and vbs), and group 2, having three homologues (avna, verb, and vbs). here, partial aflatoxin homologous gene cluster of rib62 from group 2 was sequenced and compared with that of rib40 from group 1. rib62 showed a large deletion upstream of ver-1 with more than half of the aflatoxin homologous gene cluster missing including aflr, a positive ...200616673111
[production of antitumor substances from shochu distillation remnants].this study aimed to develop a new processing method for the effective use of rice shochu distillation remnants. we examined the inhibitory effects on the growth of human lung carcinoma cells in the medium of rice shochu distillation remnants with various fungi. interestingly, high inhibitory effects on the growth of human lung carcinoma cells in the medium of rice shochu distillation remnants with aspergillus oryzae were obtained, although no inhibitory effect was observed in the case of synthet ...200616679744
[genome sequencing of aspergillus oryzae]. 200616686348
development of aflp-derived, functionally specific markers for environmental persistence studies of fungal strains.the ability to rapidly identify and quantify a microbial strain in a complex environmental sample has widespread applications in ecology, epidemiology, and industry. in this study, we describe a rapid method to obtain functionally specific genetic markers that can be used in conjunction with standard or real-time polymerase chain reaction (pcr) to determine the abundance of target fungal strains in selected environmental samples. the method involves sequencing of randomly cloned aflp (amplified ...200616699570
square-plate culture method allows detection of differential gene expression and screening of novel, region-specific genes in aspergillus oryzae.when grown on solid agar medium, the mycelium of a filamentous fungus, aspergillus oryzae, forms three morphologically distinct regions: the tip (t), white (w), and basal (b) regions. in this study, we developed the square-plate culture method, a novel culture method that enabled the extraction of mrna samples from the three regions and analyzed the differential gene expression of the a. oryzae mycelium in concert with the microarray technique. expression of genes involved in protein synthesis w ...200616708193
functional expression of candida antarctica lipase b in eschericha coli.candida antarctica lipase b (calb) is an important catalyst in bio-organic synthesis. to optimize its performance, either the reaction medium is changed or the lipase itself is modified. in the latter case, mutants are generated in eschericha coli and subsequently expressed in fungal hosts for their characterization. here we present the functional expression of calb in the periplasm of e. coli. by step-wise deletion of the calb signal and propeptide we were able to express and purify two differe ...200616713003
5' untranslated region of the hsp12 gene contributes to efficient translation in aspergillus oryzae.we describe a 5' untranslated region (5'utr) that dramatically increases the expression level of an exogenous gene in aspergillus oryzae. using a series of 5'utr::gus (uida) fusion constructs, we analyzed the translation efficiency of chimeric mrnas with different 5'utrs at different temperatures. we found that the 5'utr of a heat-shock protein gene, hsp12, greatly enhanced the translation efficiency of the chimeric gus mrna at normal temperature (30 degrees c). moreover, at high temperature (37 ...200616059686
hydrolase-catalyzed michael addition of imidazoles to acrylic monomers in organic medium.hydrolase-catalyzed michael addition of imidazole derivatives to acrylic monomers in organic medium was described. a serial of n-substituted imidazole derivatives were successfully synthesized in moderate yields by the catalysis of hydrolases in organic medium. nine commercially available hydrolases from different sources were screened and all of them were found to be able to catalyze this type of addition reaction. the reaction yields depended on the solvent properties and the solvents with hig ...200616099065
an aspergillus oryzae acetyl xylan esterase: molecular cloning and characteristics of recombinant enzyme expressed in pichia pastoris.we screened 20,000 clones of an expressed sequence tag (est) library from aspergillus oryzae (http://www.nrib.go.jp/ken/est/db/index.html) and obtained one cdna clone encoding a protein with similarity to fungal acetyl xylan esterase. we also cloned the corresponding gene, designated as aoaxe, from the genomic dna. the deduced amino acid sequence consisted of a putative signal peptide of 31-amino acids and a mature protein of 276-amino acids. we engineered aoaxe for heterologous expression in p. ...200616129506
change in hyphal morphology of aspergillus oryzae during fed-batch cultivation.industrial enzymes are often produced by filamentous fungi in fed-batch cultivations. during cultivation, the different morphological forms displayed by the fungi have an impact on the overall production. the morphology of a recombinant lipase producing aspergillus oryzae strain was investigated during fed-batch cultivations. during the exponential batch phase of the fed-batch cultivations, the average hyphal length increased as did the number of tips per hyphal element. most striking was the fi ...200616133324
functional characterization of delta9 and omega9 desaturase genes in mortierella alpina 1s-4 and its derivative mutants.cloning and characterization of the delta9 desaturase (delta9i) gene of a fungus, mortierella alpina 1s-4, was previously reported. in this study, two genes encoding delta9 desaturase homologs were isolated from this fungus. one is a delta9 desaturase (delta9ii) that exhibits 86% amino acid sequence similarity to delta9i. functional analysis involving expression of the encoding gene in aspergillus oryzae revealed that delta9ii exhibits delta9 desaturase activity, 18:0 being converted to 18:1delt ...200616133334
identification of secreted proteins of aspergillus oryzae associated with growth on solid cereal substrates.filamentous growth of aspergillus oryzae on solid cereal substrates involves secretion of substrate converting enzymes and a solid substrate specific polarised hyphal growth phenotype. to identify proteins produced under these specific conditions, the extracts of a. oryzae grown on wheat-based media were analysed using n-terminal sequence analysis. in a submerged wheat-based growth medium of a. oryzae, besides alpha-amylase, also an arabinosidase and xylanase were abundantly produced. in the ext ...200616226332
the fungal hydrophobin rola recruits polyesterase and laterally moves on hydrophobic surfaces.when fungi grow on plant or insect surfaces coated with wax polyesters that protect against pathogens, the fungi generally form aerial hyphae to contact the surfaces. aerial structures such as hyphae and conidiophores are coated with hydrophobins, which are surface-active proteins involved in adhesion to hydrophobic surfaces. when the industrial fungus aspergillus oryzae was cultivated in a liquid medium containing the biodegradable polyester polybutylene succinate-coadipate (pbsa), the rola gen ...200516135240
genotyping of madurella mycetomatis by selective amplification of restriction fragments (amplified fragment length polymorphism) and subtype correlation with geographical origin and lesion size.one of the causative organisms of mycetoma is the fungus madurella mycetomatis. previously, extensive molecular typing studies identified sudanese isolates of this fungus as clonal, but polymorphic genetic markers have not yet been identified. here, we report on the selective amplification of restriction fragment (aflp) analysis of 37 sudanese clinical isolates of m. mycetomatis. of 93 aflp fragments generated, 25 were polymorphic, and 12 of these 25 polymorphic fragments were found in a large f ...200516145076
thermostability of irreversible unfolding alpha-amylases analyzed by unfolding kinetics.for most multidomain proteins the thermal unfolding transitions are accompanied by an irreversible step, often related to aggregation at elevated temperatures. as a consequence the analysis of thermostabilities in terms of equilibrium thermodynamics is not applicable, at least not if the irreversible process is fast with respect the structural unfolding transition. in a comparative study we investigated aggregation effects and unfolding kinetics for five homologous alpha-amylases, all from mesop ...200516150692
nuclear translocation of the heterotrimeric ccaat binding factor of aspergillus oryzae is dependent on two redundant localising signals in a single subunit.the ccaat-binding complex in the aspergillus species, also known as the hap complex, consists of at least three subunits, namely hapb, hapc and hape. each hap subunit contains an evolutionary conserved core domain. recently, we have found that the hapc and hape subunits do not carry a nuclear localisation signal. furthermore, when in complex with hapb, they are transported into the nucleus via a 'piggy back mechanism' in a. nidulans. to extend our findings to other filamentous fungi, we examined ...200516163515
genomic evidences for the existence of a phenylpropanoid metabolic pathway in aspergillus oryzae.plants interact with their environment by producing a diverse array of secondary metabolites. a majority of these compounds are phenylpropanoids and flavonoids which are valued for their medicinal and agricultural properties. the phenylpropanoid biosynthesis pathway proceeds with the basic c6-c3 carbon skeleton of phenylalanine, and involves a wide range of enzymes viz., phenylalanine ammonia lyase, coumarate hydroxylase, coumarate ligase, chalcone synthase, chalcone reductase and chalcone isome ...200516182237
nonribosomal peptide synthetase genes in the genome of fusarium graminearum, causative agent of wheat head blight.fungal nonribosomal peptide synthetases (nrpss) are responsible for the biosynthesis of numerous metabolites which serve as virulence factors in several plant-pathogen interactions. the aim of our work was to investigate the diversity of these genes in a fusarium graminearum sequence database using bioinformatic techniques. our search identified 15 nrps sequences, among which two were found to be closely related to peptide synthetases of various fungi taking part in ferrichrome biosynthesis. ano ...200516196211
what the aspergillus genomes have told us.the sequencing and annotation of the genomes of the first strains of aspergillus nidulans, aspergillus oryzae, and aspergillus fumigatus will be seen in retrospect as a transformational event in aspergillus biology. with this event the entire genetic composition of a. nidulans, the sexual experimental model organism of the genus aspergillus, a. oryzae, the food biotechnology organism which is the product of centuries of cultivation, and a. fumigatus, the most common causative agent of invasive a ...200516110785
antihypertensive effect of casein hydrolysate in a placebo-controlled study in subjects with high-normal blood pressure and mild hypertension.we describe a clinical trial to study the efficacy of a casein hydrolysate, prepared using an aspergillus oryzae protease, containing the major angiotensin-i-converting enzyme inhibitory peptides val-pro-pro (vpp) and ile-pro-pro (ipp) in a single-blind, placebo-controlled study. a total of 131 volunteers with high-normal blood pressure and mild hypertension were randomly divided into four groups (n 32 or 33 in each group). each volunteer was given two tablets containing four different dosages o ...200516115337
isolation and characterization of aspergillus oryzae vacuolar protein sorting mutants.the vacuolar protein sorting (vps) system in the filamentous fungus aspergillus oryzae, which has unique cell polarity and the ability to secrete large amounts of proteins, was evaluated by using mutants that missort vacuolar proteins into the medium. vacuolar carboxypeptidase y (cpy) fused with enhanced green fluorescent protein (egfp) was used as a vacuolar marker. twenty dfc (dim egfp fluorescence in conidia) mutants with reduced intracellular egfp fluorescence in conidia were isolated by flu ...200516085884
enrichment of cheeses manufactured from cow's and sheep's milk blends with sheep-like species-related alkylphenols.enhancement of concentrations of species-related sheep-like alkylphenols, p- and m-cresols and 3- and 4-ethylphenols, in experimental manchego-type cheeses manufactured from cow's and sheep's milk blends (80:20) by using arylsulfatases was investigated. a food-grade arylsulfatase from aspergillus oryzae (atcc 20719) was produced using a stimulatory medium, and crude dried cells were used as the enzyme source. exogenous arylsulfatases from helix pomatia and a. oryzae were added to cheese curd, an ...200515740062
effect of low oxygen concentrations on growth and alpha-amylase production of aspergillus oryzae in model solid-state fermentation systems.oxygen transfer in the fungal mat is a major concern in solid-state fermentation (ssf). oxygen supply into the mycelial layers is hampered by diffusion limitation. for aerobic fungi, like aspergillus oryzae, this oxygen depletion can be a severely limiting factor for growth and metabolite production. this paper describes the effects of a low oxygen concentration on growth at the levels of individual hyphae, colonies and overcultures, and on alpha-amylase production in overcultures. pda medium wa ...200515748690
purification and characterization of a biodegradable plastic-degrading enzyme from aspergillus oryzae.we used biodegradable plastics as fermentation substrates for the filamentous fungus aspergillus oryzae. this fungus could grow under culture conditions that contained emulsified poly-(butylene succinate) (pbs) and emulsified poly-(butylene succinate-co-adipate) (pbsa) as the sole carbon source, and could digest pbs and pbsa, as indicated by clearing of the culture supernatant. we purified the pbs-degrading enzyme from the culture supernatant, and its molecular mass was determined as 21.6 kda. t ...200515968570
fructosyl-amino acid oxidases of aspergillus oryzae are induced by the reaction product, glucosone.aspergillus oryzae has two fructosyl-amino acid oxidase (faod) isozymes (aofao1 and aofao2), which are different in the substrate specificities. northern blot analysis showed both fao genes were induced by autoclave-browned medium containing l-lysine or l-valine. studies with a mutant, that had a disrupted aofao2 gene, revealed that the expression of aofao1 by fructosyl l-valine depended on the expression of aofao2. both genes were also induced by one of the faod-reaction products, glucosone. in ...200515972252
copper-dependent production of a pycnoporus coccineus extracellular laccase in aspergillus oryzae and saccharomyces cerevisiae.laccase is a multicopper-containing enzyme that catalyzes the oxidation of phenolic compounds. lcc1 cdna coding for a secretory laccase of pycnoporus coccineus was expressed under the maltose inducible amyb promoter in aspergillus oryzae and under the galactose inducible gal10 promoter in saccharomyces cerevisiae. laccase activities, which were undetectable in the absence of copper, were observed by increasing copper concentrations in the media for both systems. the amounts of secreted laccase p ...200515973039
[overexpression of aspergillus candidus lactase and analysis of enzymatic properties].the lactase gene lacb' from aspergillus candidus was fused behind alpha-factor signal sequence in the pichia pastoris expression vector ppic9, then integrated into the genome of p. pastoris by recombination events. the p. pastoris recombinants for lactase overexpression were screened by enzyme activity analysis and sds-page. the lactase expressed in p. pastoris was glycosylated protein with an apparent molecular weight of 130 kd, while the deglycosylated lactase treated with endo h had an appare ...200515989270
characterization of salt-tolerant glutaminase from stenotrophomonas maltophilia nyw-81 and its application in japanese soy sauce fermentation.glutaminase from stenotrophomonas maltophilia nyw-81 was purified to homogeneity with a final specific activity of 325 u/mg. the molecular mass of the native enzyme was estimated to be 41 kda by gel filtration. a subunit molecular mass of 36 kda was measured with sds-page, thus indicating that the native enzyme is a monomer. the n-terminal amino acid sequence of the enzyme was determined to be keaetqqklanvvilatggtia. besides l: -glutamine, which was hydrolyzed with the highest specific activity ...200516012776
synthesis of morphiceptin (tyr-pro-phe-pro-nh(2)) by dipeptidyl aminopeptidase iv derived from aspergillus oryzae.morphiceptin (tyr-pro-phe-pro-nh(2)), tetrapeptide, was synthesized using dipeptidyl aminopeptidase iv (dp iv, ec 3.4.14.5) derived from aspergillus oryzae rib 915 as a catalyst. tyr-pro-oet was incubated with phe-pro-nh(2) in the presence of dp iv under various conditions of temperature, concentrations of ethylene glycol, ph, reaction time, and others. morphiceptin was obtained at 40% yield under the optimal reaction conditions: substrate, 4 mm tyr-pro-oet.hcl and 20 mm phe-pro-nh(2).hcl; enzym ...200516029004
acidolysis between triolein and short-chain fatty acid by lipase in organic solvents.ten kinds of lipases were examined as biocatalysts for the incorporation of short-chain fatty acids (acetic, propionic, and butyric acids) into triolein in order to produce one kind of reduced-calorie structured lipids. trans-esterification (acidolysis) was successfully done in n-hexane by several microbial lipases. among them, lipase from aspergillus oryzae was used to investigate the effects of incubation time, substrate molar ratio, and water content on acidolysis. finally, more than 80% of t ...200516041127
significance of bed porosity, bran and specific surface area in solid-state cultivation of aspergillus oryzae.in this paper, the effects of bed porosity, bran and specific surface area on the oxygen uptake rate and alpha-amylase production during growth of aspergillus oryzae on wheat grain and wheat-flour substrate are reported. the high oxygen uptake rate found during cultivation of a. oryzae on wheat-flour substrate was not reached on wheat grain. this is mainly due to the bran of the wheat grain. using wheat-flour substrates, it was shown that extra bed porosity increased the alpha-amylase production ...200516046183
expression of the fusarium oxysporum lactonase gene in aspergillus oryzae: molecular properties of the recombinant enzyme and its application.the lactonase gene of fusarium oxysporum was expressed in aspergillus oryzae for optical resolution of dl-pantoyl lactone. when the chromosomal gene encoding the full-length form of the lactonase, which has its own nh2-terminal signal peptide, was introduced in the host cells, the resulting transformant produced an enzyme of 46,600 da, which corresponded to the wild-type enzyme. in contrast, a. oryzae transformed with the cdna coding the mature enzyme produced a protein of 41,300 da. deglycosyla ...200515503009
aspergillus oryzae produces compounds inhibiting cholesterol biosynthesis downstream of dihydrolanosterol.the formation of cholesterol synthesis inhibiting molecules by five different strains of the koji mold aspergillus oryzae was studied. after growing these strains on a complex liquid medium we found in crude organic phase extracts and specific fractions there from compounds inhibiting cholesterol synthesis in human hepatic t9a4 cells in vitro at enzyme sites downstream of dihydrolanosterol. this was evidenced by using different radioactively labeled precursors, namely acetate, mevalonate, 24,25- ...200515621432
effect of cycle time on fungal morphology, broth rheology, and recombinant enzyme productivity during pulsed addition of limiting carbon source.for many years, high broth viscosity has remained a key challenge in large-scale filamentous fungal fermentations. in previous studies, we showed that broth viscosity could be reduced by pulsed addition of limiting carbon during fed-batch fermentation. the objective in this study was to determine how changing the frequency of pulsed substrate addition affects fungal morphology, broth rheology, and recombinant enzyme productivity. to accomplish this, a series of duplicate fed-batch fermentations ...200515643626
synthesis of ethyl phenylacetate by lyophilized mycelium of aspergillus oryzae.lyophilized mycelia of aspergillus oryzae cbs 102.07, aspergillus oryzae mim, rhizopus oryzae cbs 112.07, rhizopus oryzae cbs 391.34, rhizopus oryzae cbs 260.28 and rhizopus oryzae cbs 328.47 were tested in this study to select the best biocatalysts for ethanol acylation with phenylacetic acid. the mycelium-bound carboxylesterase activity of a. oryzae mim, which exhibited the best performances, was initially investigated at 50 degrees c, either in 0.1 m phosphate buffer or in n-heptane to cataly ...200515650849
improvement of the aspergillus oryzae enolase promoter (p-enoa) by the introduction of cis-element repeats.we constructed a protein expression vector with an improved enoa promoter that harbored 12 tandem repeats of the cis-acting element (region iii) of aspergillus oryzae. the improved promoter yielded reporter beta-glucuronidase (gus) activity approximately 30-fold of the original promoter. northern blot analysis confirmed that gus expression was increased at the transcriptional level. the transformant harboring seven copies of the novel vector showed more than 100,000 u/mg gus protein, which was a ...200515665487
identification of growth phenotype-related genes in aspergillus oryzae by heterologous macroarray and suppression subtractive hybridization.aspergillus oryzae requires polarized growth for colonization of solid substrates, and this growth phenotype differs from that seen in liquid medium. various experimental approaches were used to identify genes that are differentially expressed when a. oryzae is grown on wheat kernels and in a wheat-based liquid medium. hybridization of a. oryzae rnas to a macroarray bearing cdnas isolated from a library representing at least 16% of the total number of a. niger genes identified 14 differentially ...200515678358
some properties of two aldolases in extracts of aspergillus oryzae.fructose 1,6-diphosphate (fdp) aldolase and 2-keto-3-deoxy-d-gluconate (kdg) aldolase the two key enzymes of embden-meyerhof-parnas (emp) and the nonphosphorolytic entner-doudoroff (ed) pathways respectively, were identified in cell-free extracts of four aspergillus oryzae strains grown on d-glucose as sole source of carbon. a. oryzae nrrl 3435 gave the highest enzymatic activity for the two enzymes and selected for further studies. studies on the properties of the two key enzymes indicated that ...200515678561
structural and mechanistic studies of chloride induced activation of human pancreatic alpha-amylase.the mechanism of allosteric activation of alpha-amylase by chloride has been studied through structural and kinetic experiments focusing on the chloride-dependent n298s variant of human pancreatic alpha-amylase (hpa) and a chloride-independent taka-amylase. kinetic analysis of the hpa variant clearly demonstrates the pronounced activating effect of chloride ion binding on reaction rates and its effect on the ph-dependence of catalysis. structural alterations observed in the n298s variant upon ch ...200515722449
double mutant of aspergillus oryzae for improved production of l-dopa (3,4-dihydroxyphenyl-l-alanine) from l-tyrosine.aspergillus oryzae mutant strain uv-7 was further improved for the production of l-dopa from l-tyrosine using chemical mutation. different putative mutant strains of the organism were tested for the production of l-dopa in triplicate shake-flask cultures. among these putative mutants, the strain designated si-12 gave a maximal production of l-dopa (444+/-14 mg of l-dopa/g of cells). the regulation of l-dopa from different carbon source solutions [initial substrate concentration (s(0))=30 g/l] by ...200515727563
development of aspergillus oryzae thia promoter as a tool for molecular biological studies.in filamentous fungi, the repertoire of promoters available for exogenous gene expression is limited. here, we report the development and application of the thiamine-regulatable thia promoter (pthia) in aspergillus oryzae as a tool for molecular biological studies. when pthia was used to express the enhanced green fluorescent protein (egfp) reporter, the fluorescence in the mycelia was either repressed or induced in the presence or absence of thiamine in the culture media, respectively. in addit ...200515727819
high-level expression of myrothecium verrucaria bilirubin oxidase in pichia pastoris, and its facile purification and characterization.bilirubin oxidase (bo) from myrothecium verrucaria (authentic bo) catalyzing the oxidation of bilirubin to biliverdine was overexpressed in the methylotrophic yeast, pichia pastoris. the cdna encoding bo was cloned into the p. pastoris expression vector ppic9k under the control of the alcohol oxidase 1 promoter and its protein product was secreted using the saccharomyces cerevisiae alpha-mating factor signal sequence. the productivity of recombinant bo (rbo) in p. pastoris was approximately 5000 ...200515802224
discovery of a novel superfamily of type iii polyketide synthases in aspergillus oryzae.identification of genes encoding type iii polyketide synthase (pks) superfamily members in the industrially useful filamentous fungus, aspergillus oryzae, revealed that their distribution is not specific to plants or bacteria. among other aspergilli (aspergillus nidulans and aspergillus fumigatus), a. oryzae was unique in possessing four chalcone synthase (chs)-like genes (csya, csyb, csyc, and csyd). expression of csya, csyb, and csyd genes was confirmed by rt-pcr. comparative genome analyses r ...200515845386
visualizing nuclear migration during conidiophore development in aspergillus nidulans and aspergillus oryzae: multinucleation of conidia occurs through direct migration of plural nuclei from phialides and confers greater viability and early germination in aspergillus oryzae.nuclear migration is indispensable for normal growth, differentiation, and development, and has been studied in several fungi including aspergillus nidulans and neurospora crassa. to better characterize nuclear movement and its consequences during conidiophore development, conidiation, and conidial germination, we performed confocal microscopy and time-lapse imaging on a. nidulans and aspergillus oryzae strains expressing the histone h2b-egfp fusion protein. active trafficking of nuclei from a v ...200515849413
allosteric nadp-glutamate dehydrogenase from aspergilli: purification, characterization and implications for metabolic regulation at the carbon-nitrogen interface.nadp-dependent glutamate dehydrogenase (nadp-gdh) mediates fungal ammonium assimilation through reductive synthesis of glutamate from 2-oxoglutarate. by virtue of its position at the interface of carbon and nitrogen metabolism, biosynthetic nadp-gdh is a potential candidate for metabolic control. in order to facilitate characterization, a new and effective dye-affinity method was devised to purify nadp-gdh from two aspergilli, aspergillus niger and aspergillus nidulans. the a. niger nadp-gdh was ...200515870451
three-dimensional image analysis of plugging at the septal pore by woronin body during hypotonic shock inducing hyphal tip bursting in the filamentous fungus aspergillus oryzae.we observed that the filamentous fungus, aspergillus oryzae, grown on agar media burst out cytoplasmic constituents from the hyphal tip soon after flooding with water. woronin body is a specialized organelle known to plug the septal pore adjacent to the lysed compartment to prevent extensive loss of cytoplasm. a. oryzae aohex1 gene homologous to neurospora crassa hex1 gene encoding a major protein in woronin body was expressed as a fusion with dsred2, resulting in visualization of woronin body. ...200515882988
repeated-batch production of kojic acid in a cell-retention fermenter using aspergillus oryzae m3b9.a cell-retention fermenter was used for the pilot-scale production of kojic acid using an improved strain of aspergillus oryzae in repeated-batch fermentations. among the various carbon and nitrogen sources used, sucrose and yeast extract promoted pellet morphology of fungi and higher kojic acid production. repeated-batch culture using a medium replacement ratio of 75% gave a productivity of 5.3 gl(-1)day(-1) after 11.5 days of cultivation. while batch culture in shake-flasks resulted in a produ ...200515895266
grifolisin, a member of the sedolisin family produced by the fungus grifola frondosa.the pepstatin-insensitive carboxyl proteinase grifolisin was purified from fruiting bodies of the fungus grifola frondosa, a maitake mushroom. the enzyme had an optimum ph of 3.0 for the digestion of hemoglobin and 2.8 for milk casein digestion. its molecular mass was determined to be 43kda by sds-page and 40kda by gel chromatography on superose 12, and its isoelectric point was found to be 4.6 by isoelectric focusing. the enzyme hydrolyzed four major bonds in the oxidized insulin b-chain: phe1- ...200515896366
branching mutants of aspergillus oryzae with improved amylase and protease production on solid substrates.to study the relation between the number of hyphal tips and protein secretion during growth on a solid substrate, we have constructed two mutant strains of aspergillus oryzae with increased hyphal branching. we have analysed hydrolytic enzyme activities during growth on wheat kernels (wk) of a. oryzae strains carrying the disrupted allele of the pcla gene encoding a secretion pathway specific (kex2-like) endo-protease and the disrupted allele of the pg/pi-tp gene encoding a phosphatidylglycerol/ ...200515909137
identification and characterization of rns4/vps32 mutation in the rnase t1 expression-sensitive strain of saccharomyces cerevisiae: evidence for altered ambient response resulting in transportation of the secretory protein to vacuoles.we previously reported a genetic analysis of the growth-inhibitory effect caused by the overexpression of the aspergillus oryzae rnta gene, encoding rnase t1 (ribonuclease t1), in saccharomyces cerevisiae. subsequently, rns (ribonuclease t1 sensitive) mutants with mutations in the rns1 (dsl1), rns2 (ump1), and rns3 (sec17) genes, were identified. in the present study, rns4 (vps32/snf7) gene mutation was identified by complementation of tunicamycin sensitivity. while the rns4 mutant exhibited sen ...200515925308
xylanase production by fungal strains on spent sulphite liquor.xylanase production by seven fungal strains was investigated using concentrated spent sulphite liquor (sslc), xylan and d: -xylose as carbon substrates. an sslc-based medium induced xylanase production at varying levels in all of these strains, with aspergillus oryzae nrrl 3485 and aspergillus phoenicis atcc 13157 yielding activities of 164 and 146 u ml(-1), respectively; these values were higher than those obtained on xylan or d: -xylose with the same fungal strains. the highest xylanase activi ...200515944854
extraction of milk-clotting enzyme produced by solid state fermentation of aspergillus oryzae.studies on the extraction of milk-clotting enzyme after solid-state fermentation (ssf) of wheat bran by a local strain of aspergillus oryzae ls1 were done. the extraction of the enzyme was found to be depended on different parameters like nature of extractant, soaking time, temperature etc. from different inorganic and organic extractants, calcium chloride (0.05%) and glycerol (40%) were found to be the best solvents for leaching out milk-clotting enzyme. the optimum volume of calcium chloride w ...200516450841
growth and amylase production by aspergillus oryzae during solid state fermentation using banana waste as substrate.aspergillus oryzae, isolated from the starch rich litter soil, produced amylase when banana fruit stalk was used as substrate in a solid state fermentation system. the effects of incubation period, ph, temperature and various carbon sources on the production of amylase were studied. a maximum yield of 380u/mg was recorded on 96th hour of incubation. the amylase is tolerant to wide range of initial culture ph values (3 to 8) and temperature (25 to 35 degrees c), with an optimum ph of 5 and temper ...200516459551
genomics reveals traces of fungal phenylpropanoid-flavonoid metabolic pathway in the f ilamentous fungus aspergillus oryzae.fungal secondary metabolites constitute a wide variety of compounds which either play a vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. a majority of the funga ...200516410762
studies of the toxicological potential of tripeptides (l-valyl-l-prolyl-l-proline and l-isoleucyl-l-prolyl-l-proline): iii. single- and/or repeated-dose toxicity of tripeptides-containing lactobacillus helveticus-fermented milk powder and casein hydrolysate in rats.the objective of these studies was to assess the toxicological potential of orally administered tripeptides in rats. the studies employed powdered l-valyl-l-prolyl-l-proline (vpp)- and l-isoleucyl-l-prolyl-l-proline (ipp)-containing test articles, including (1) powdered lactobacillus helveticus-fermented milk (fm), (2) pasteurized casein hydrolysate (ch) generated by aspergillus oryzae protease, and (3) synthesized vpp. all test articles were administered by oral gavage to male and female spragu ...200516419576
studies of the toxicological potential of tripeptides (l-valyl-l-prolyl-l-proline and l-isoleucyl-l-prolyl-l-proline): v. a 13-week toxicity study of tripeptides-containing casein hydrolysate in male and female rats.the objective of this multiple-dose toxicity study was to assess the toxicological potential of two tripeptides, l-valyl-l-prolyl-l-proline (vpp) and l-isoleucyl-l-prolyl-l-proline (ipp), when administered once daily for 91 consecutive days to rats. the test article, powdered casein hydrolysate (ch) known to contain 0.6% vpp plus ipp, was prepared using aspergillus oryzae protease. prior to administration to the rats by oral gavage, the test article was suspended in sterile water. groups of 12 m ...200516419578
studies of the toxicological potential of tripeptides (l-valyl-l-prolyl-l-proline and l-isoleucyl-l-prolyl-l-proline): vii. micronucleus test of tripeptides-containing casein hydrolysate and lactobacillus helveticus-fermented milk powders in rats and mice.the objective of these in vivo experiments was to assess the mutagenic potential of tripeptides as reflected by the ability of the test compound to induce the formation of micronuclei in mouse polychromatic erythrocytes. the test agents used in these experiments were (1) powdered aspergillus oryzae protease casein hydrolysate (ch) and (2) powdered lactobacillus helveticus-fermented milk (fm). both test agents contain two tripeptides, l-valyl-l-prolyl-l-proline (vpp) and l-isoleucyl-l-prolyl-l-pr ...200516419580
micrococcus luteus k-3-type glutaminase from aspergillus oryzae rib40 is salt-tolerant.aspergillus oryzae rib40 possesses the gene of glutaminase (micrococcus luteus k-3-type glutaminase; aogls), which has 40% homology with the salt-tolerant glutaminase from m. luteus k-3 (micrococcus glutaminase). it was found that aogls is a salt-tolerant enzyme, and its properties are similar to those of micrococcus glutaminase.200516384800
an iterative type i polyketide synthase pksn catalyzes synthesis of the decaketide alternapyrone with regio-specific octa-methylation.a biosynthetic gene cluster containing five genes, alt1-5, was cloned from alternaria solani, a causal fungus of early blight disease to tomato and potato. homology searching indicated that the alt1, 2, and 3 genes code for cytochrome p450s and the alt4 gene for a fad-dependent oxygenase/oxidase. the alt5 gene encodes a polyketide synthase (pks), named pksn, that was found to be an iterative type i complex reduced-type pks with a c-methyltransferase domain. to identify the pksn function, the alt ...200516356847
sequencing of aspergillus nidulans and comparative analysis with a. fumigatus and a. oryzae.the aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. here we report the genome sequence of the model organism aspergillus nidulans, and a comparative study with aspergillus fumigatus, a serious human pathogen, and aspergillus oryzae, used in the production of sake, miso and soy sauce. our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. it also led to an experimentally va ...200516372000
genome sequencing and analysis of aspergillus oryzae.the genome of aspergillus oryzae, a fungus important for the production of traditional fermented foods and beverages in japan, has been sequenced. the ability to secrete large amounts of proteins and the development of a transformation system have facilitated the use of a. oryzae in modern biotechnology. although both a. oryzae and aspergillus flavus belong to the section flavi of the subgenus circumdati of aspergillus, a. oryzae, unlike a. flavus, does not produce aflatoxin, and its long histor ...200516372010
development of a modified positive selection medium that allows to isolate aspergillus oryzae strains cured of the integrated niad-based plasmid.the nitrate reductase gene (niad) is the most frequently utilized as a selectable marker for homologous integration at the niad locus of aspergillus oryzae. in this study we developed a method for curing of the niad-based plasmid integrated on the a. oryzae genome. positive selection using a modified chlorate medium containing leucine as a nitrogen source enabled efficient isolation of the strains deficient in nitrate assimilation from the niad(+) transformant. pcr analysis of the strains confir ...200516377911
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