| operational stability of enzymes. acylase-catalyzed resolution of n-acetyl amino acids to enantiomerically pure l-amino acids. | the method of measuring enzyme deactivation by monitoring necessary addition of fresh enzyme to keep a constant degree of conversion in a cstr at constant [e] x tau, the product of concentration of active enzyme [e] and residence time tau, was successfully applied to acylase i from porcine kidney and aspergillus oryzae fungus. fungal enzyme was found to be more stable than kidney enzyme. activation by both co2+ and zn2+ ions also yielded increased operational enzyme stability: co2+ and zn2+ are ... | 1992 | 1476369 |
| comparison of the domain-level organization of starch hydrolases and related enzymes. | structure-prediction and hydrophobic-cluster analysis of several starch hydrolases and related enzymes indicated the organization of eleven domain types. most enzymes possess a catalytic (beta/alpha)8-barrel and a smaller c-terminal domain as seen in crystal structures of alpha-amylase and cyclodextrin glucanotransferase. some also have a starch-granule-binding domain. enzymes breaking or forming endo-alpha-1,6 linkages contain domains n-terminal to the (beta/alpha)8-barrel. | 1991 | 1741756 |
| hydrophobic cluster analysis of the primary sequences of alpha-amylases. | the amino acid sequences of 18 alpha-amylases have been compared by hydrophobic cluster analysis. the method was first calibrated with two alpha-amylases (aspergillus oryzae and pig pancreas) whose three-dimensional structures are known. it was then applied to the other alpha-amylases resulting in straightforward sequence alignments which could be used for structure prediction. it was found that all alpha-amylases which were investigated display the same basic super-secondary structure with a (b ... | 1989 | 2489084 |
| nutritive value of whole soybeans fermented with aspergillus oryzae or rhizopus oligosporus as evaluated by neonatal pigs. | two experiments were conducted to evaluate the nutritive effects of heated whole soybeans fermented with the mold aspergillus oryzae (aos) or rhizopus oligosporus (ros) in diets fed to neonatal pigs from 1 to 22 d of age. in experiment 1, either soybean meal or heated whole soybeans fermented with ros replaced 75% of the dried skim milk protein. the average daily gain (adg) and gain-feed (g-f) ratio of pigs fed the diet containing 100% milk protein were greater than those of pigs fed the diets c ... | 1988 | 3357058 |
| alpha-amylase inhibitor from fungus cladosporium herbarum f-828. | a strain of fungus cladosporium herbarum extracellularly produced an inhibitor specific for mammalian alpha-amylase. the inhibitor was purified 81-fold by freeze-thawing, heat treatment, and column chromatography on deae-cellulose, sephadex g-75, deae-sephacel, and bio-gel p-100. an apparent molecular weight of approximately 18,000 was estimated for the inhibitor using bio-gel p-100 filtration. the purified inhibitor preparation was a glycoprotein containing about 10% carbohydrate. the amino aci ... | 1982 | 6174515 |
| a new chromophoric substrate for penicillopepsin and other fungal aspartic proteinases. | the hexapeptide n-alpha-acetylalanylalanyl-lysyl-p- nitrophenylalanylalanylalanylamide has been synthesized and was found to be a good substrate for fungal aspartic proteinases that possess trypsinogen-activating activity, namely penicillopepsin, rhizopus aspartic proteinase, endothia aspartic proteinase and the aspartic proteinases from aspergillus oryzae and penicillium roqueforti. the peptide is rapidly cleaved between the lysine and p-nitrophenylalanine residues. calf chymosin and human reni ... | 1982 | 7052062 |
| structure-function relationships in naturally occurring mutants of pancreatic lipase. | from primary structure comparison, the pancreatic lipase family is now divided into three subgroups: classical pancreatic lipases, pancreatic lipase-related proteins 1 (rpi) and pancreatic lipase-related proteins 2 (rp2). among the rp2 subfamily, the guinea-pig and coypu enzymes share kinetic properties which differ from those of classical pancreatic lipases. both enzymes display a high phospholipase activity and are not interfacially activated using a short chain triglyceride as substrate. thei ... | 1994 | 8029213 |
| glycoprotein e2 of classical swine fever virus: expression in insect cells and identification as a ribonuclease. | two regions of amino acids homologous to the ribonuclease catalysis domain of the fungal rnases t2 of aspergillus oryzae and rh of rhizopus niveus and the plant s-glycoproteins of nicotiana alata are perfectly conserved in the amino acid sequence of the envelope glycoprotein e2 of classical swine fever virus (csfv). to analyze the functional significance of these conserved sequences, the gene encoding e2 was inserted into the p10 locus of baculovirus and expressed in insect cells. recombinant vi ... | 1994 | 8178442 |
| polypeptide folding of bacillus cereus atcc7064 oligo-1,6-glucosidase revealed by 3.0 a resolution x-ray analysis. | the crystal structure of an oligo-1,6-glucosidase from bacillus cereus atcc7064 was determined by the x-ray diffraction method at 3.0 a resolution. the structure was solved by the multiple isomorphous replacement method and refined to a crystallographic r-factor of 0.208, using the molecular dynamics refinement program, x-plor. the electron density map revealed the folding of a polypeptide chain consisting of 558 amino acid residues. the molecule can be subdivided into three domains (n-terminal ... | 1993 | 8370659 |
| safety evaluation of a lipase expressed in aspergillus oryzae. | a programme of studies was conducted to establish the safety of a lipase artificially expressed in aspergillus oryzae to be used in the detergent industry and as a processing aid in the baking industry. laboratory animal studies were used to assess general and inhalation toxicity, skin sensitization, and skin and eye irritation. its potential to cause mutagenicity and chromosomal aberrations was assessed in microbial and tissue culture in vitro studies. the pathogenicity of a. oryzae, the organi ... | 1996 | 8606032 |
| an overview of the safety evaluation of the thermomyces lanuginosus xylanase enzyme (sp 628) and the aspergillus aculeatus xylanase enzyme (sp 578). | xylanases sp 628 and sp 578 were produced by submerged fermentation of aspergillus oryzae, containing a gene code originating from thermomyces lanuginosus and aspergillus aculeatus, respectively. both enzymes were subject to the same series of toxicological tests to document their safety in use. the enzymes are to be applied as processing aids in the baking industry and in wheat starch separation. neither enzyme was found to be mutagenic in the salmonella typhimurium reverse mutation assay, nor ... | 1997 | 9205568 |
| noncompetitive, reversible inhibition of aminoacylase-1 by a series of l-alpha-hydroxyl and l-alpha-fluoro fatty acids: ligand specificity of aspergillus oryzae and porcine kidney enzymes. | l-lactate and l-beta-phenyllactate have been identified in the culture broth of streptomyces sp. ky-11 as reversible noncompetitive inhibitors of aspergillus oryzae aminoacylase-1 and porcine kidney aminoacylase i. a series of alpha-hydroxyl acids (dl-r-ch(oh)-cooh, r = et, n-pro, n-butyl, n-pentyl, n-hexyl) also inhibited the two enzymes in reversible noncompetitive kinetics, and the inhibition potency (-log k(i)) increased with the increased hydrophobicity of the r group. the two eukaryotic en ... | 2000 | 10898943 |
| identification of catalytic and substrate-binding site residues in bacillus cereus atcc7064 oligo-1,6-glucosidase. | three active site residues (asp199, glu255, asp329) and two substrate-binding site residues (his103, his328) of oligo-1,6-glucosidase (ec 3.2.1.10) from bacillus cereus atcc7064 were identified by site-directed mutagenesis. these residues were deduced from the x-ray crystallographic analysis and the comparison of the primary structure of the oligo-1,6-glucosidase with those of saccharomyces carlsbergensis alpha-glucosidase, aspergillus oryzae alpha-amylase and pig pancreatic alpha-amylase which ... | 2001 | 11676021 |
| study of the inhibition of four alpha amylases by acarbose and its 4iv-alpha-maltohexaosyl and 4iv-alpha-maltododecaosyl analogues. | acarbose analogues, 4iv-maltohexaosyl acarbose (g6-aca) and 4iv-maltododecaosyl acarbose (g12-aca), were prepared by the reaction of cyclomaltodextrin glucanyltransferase with cyclomaltohexaose and acarbose. the inhibition kinetics of acarbose and the two acarbose analogues were studied for four different alpha-amylases: aspergillus oryzae, bacillus amyloliquefaciens, human salivary, and porcine pancreatic alpha-amylases. the three inhibitors showed mixed, noncompetitive inhibition, for all four ... | 2003 | 14499573 |
| degradation of raw or film-incorporated beta-cyclodextrin by enzymes and colonic bacteria. | beta-cyclodextrin (beta-cd) is a suitable excipient for peroral use, which improves the solubility of lipophilic drugs, as well as for colon-specific drug release when it is mixed with coating polymers. the first aim of this work was to examine the suitability of various enzymes as a simple in vitro model for the glycolytic activity in the human colon. alpha-amylase (source aspergillus oryzae) and taka diastase (source a. oryzae) showed remarkable degradation capacity of free beta-cd, whereas ot ... | 2004 | 15207542 |
| airborne fungi in industrial environments--potential agents of respiratory diseases. | investigations on airborne fungi in a poultry house, a swinery, a feed preparing and storing house, a grain mill, a wooden panel producing factory, and organic waste recycling facilities have been carried out in lithuania. low concentrations of fungal spores were detected in the wooden panel producing factory, the swinery, the feed preparing and storing house, and the poultry house; moderate concentrations were found in the organic waste recycling facilities; high concentrations were revealed at ... | 2004 | 15236494 |
| 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 ... | 2005 | 16150692 |
| temperature impacts the multiple attack action of amylases. | the action pattern of several amylases was studied at 35, 50, and 70 degrees c using potato amylose, a soluble (red starch) and insoluble (cross-linked amylose) chromophoric substrate. with potato amylose as substrate, bacillus stearothermophilus alpha-amylase (bsta) and porcine pancreatic alpha-amylase displayed a high degree of multiple attack (dma, i.e., the number of bonds broken during the lifetime of an enzyme-substrate complex minus one), the fungal alpha-amylase from aspergillus oryzae a ... | 2007 | 17309295 |
| new, efficient synthesis of oseltamivir phosphate (tamiflu) via enzymatic desymmetrization of a meso-1,3-cyclohexanedicarboxylic acid diester. | a new, enantioselective synthesis of the influenza neuraminidase inhibitor prodrug oseltamivir phosphate 1 (tamiflu) and its enantiomer ent-1 starting from cheap, commercially available 2,6-dimethoxyphenol 10 is described. the main features of this approach comprise the cis-hydrogenation of 5-(1-ethyl-propoxy)-4,6-dimethoxy-isophthalic acid diethyl ester (6a) and the desymmetrization of the resultant all-cis meso-diesters 7a and 7b, respectively. enzymatic hydrolysis of the meso-diester 7b with ... | 2008 | 18517254 |
| enzymatic degradation products from a marine polysaccharide ycp with different immunological activity and binding affinity to macrophages, hydrolyzed by alpha-amylases from different origins. | ycp is a marine polysaccharide with anti-tumor and immune-modulating effects. this study evaluated the effect of enzymatic degradation of ycp by alpha-amylases from different origins on its immunological activity and binding ability to the macrophages. ycp was hydrolyzed by alpha-amylases isolated from aspergillus oryzae, bacillus licheniformis, barley malt, and porcine pancreas respectively, then four fragments with unique molecular weight (termed: ycp-ao, ycp-bl, ycp-bm, and ycp-pp, respective ... | 2010 | 20004229 |
| toxicological studies on a novel phytase expressed from synthetic genes in aspergillus oryzae. | phytases are widely used as feed additives for monogastric animals, which cannot easily utilise the phosphorus bound in phytate (myo-inositol hexakisphosphate). the current study presents a safety evaluation of a 6-phytase produced by an aspergillus oryzae strain expressing two synthetic genes, both mimicking a phytase gene from a citrobacter braakii strain. oral administration of the phytase preparation to rats at a dose level of 0.86 g total organic solids/kg body weight/day for 13 weeks did n ... | 2011 | 21672596 |