TitleAbstractYear(sorted ascending)
structural and functional analysis of the amdr regulatory gene of aspergillus oryzae.we have isolated the aspergillus oryzae homologue of the amdr regulatory gene of aspergillus nidulans by cross hybridization. sequence analysis and functional studies have shown that the amdr genes are highly conserved and functionally interchangeable between the two species. the homology between the two genes extends throughout most of the coding sequences, including sequences encoding the dna-binding domain and putative activation domains. two regions of nonconserved sequence were also identif ...19921452021
controlled mycelial growth for kojic acid production using ca-alginate-immobilized fungal cells.conidia of aspergillus oryzae were immobilized in ca-alginate beads and then incubated in a nutrient medium to yield an immobilized biocatalyst producing kojic acid. the immobilized cell cultures produced kojic acid linearly during cultivation. regardless of the size of the immobilized particles, there existed an optimal nitrogen concentration for the maximum production rate of kojic acid, at which smaller bead sizes resulted in a higher production rate. when the growth of mycelia were confined ...19921368062
cloning of the alpha-amylase cdna of aspergillus shirousamii and its expression in saccharomyces cerevisiae.alpha-amylase cdna was cloned and sequenced from aspergillus shirousamii rib2504. the putative protein deduced from the cdna open reading frame (orf) consisted of 499 amino acids with a molecular weight of 55,000. the amino acid sequence was identical to that of the orf of the taka-amylase a gene of aspergillus oryzae, while the nucleotide sequence was different at two and six positions in the cdna orf and 3' non-coding regions, respectively, so far determined. the alpha-amylase cdna was express ...19921368777
overproduction of an alpha-amylase/glucoamylase fusion protein in aspergillus oryzae using a high expression vector. 19921369066
deletion analysis of the taka-amylase a gene promoter using a homologous transformation system in aspergillus oryzae.the taka-amylase a gene (amyb) of aspergillus oryzae is induced by starch or maltose. the molecular mechanism of the induction was investigated using a fusion of the amyb promoter and the escherichia coli uida gene encoding beta-glucuronidase (gus). to identify the region responsible for high-level expression and regulation within the amyb promoter, a series of deletion promoters was constructed and introduced into the a. oryzae met locus by homologous recombination. deletion of the region betwe ...19921369079
a comparative study on the catalytic properties of guanyl-specific ribonucleases.the kinetic parameters of reactions catalyzed by four guanyl-specific rnases t1, pb1, th1 and sa were studied comparatively using three types of substrates; guanosine-2',3'-cyclophosphates, gpn dinucleoside phosphates and synthetic polyribonucleotides. the kinetic parameters were shown to be similar in spite of considerable differences in primary structures of these rnases, including amino acid residues of the active sites. therefore, primary structures of guanyl rnases allow for a considerable ...19921310940
partial purification and immobilization of ribonuclease t2.a simple procedure, consisting of water extraction, heat treatment at ph 2.0, negative adsorption on deae-cellulose at ph 4.9, and concanavalin a-sepharose chromatography, was developed for the partial purification of ribonuclease (rnase) t2 from taka-diastase powder with an overall yield of 5.5%. the partially purified enzyme when coupled to aminoethyl bio-gel p-60, retained 12-16% of the activity of the soluble enzyme. temperature stability studies on rnase t2 bound to matrices, activated with ...19921418689
structure of ribonuclease t1 complexed with zinc(ii) at 1.8 a resolution: a zn2+.6h2o.carboxylate order to study the inhibitory effect of zn2+ on ribonuclease t1 [rnase t1; itaya & inoue (1982). biochem. j. 207, 357-362], the enzyme was cocrystallized with 2 mm zn2+, ph 5.2, from a solution containing 55% (v/v) 2-methyl-2,4-pentanediol. the crystals are orthorhombic, p2(1)2(1)2(1), a = 48.71 (1), b = 46.51 (1), c = 41.14 (1) a, z = 4, v = 93203 a3. the crystal structure was determined by molecular replacement and refined by restrained least-squares methods based on fhkl for 8291 unique re ...19921515106
cultivation characteristics of immobilized aspergillus oryzae for kojic acid production.aspergillus oryzae in situ grown from spores entrapped in calcium alginate gel beads was used for the production of kojic acid. the immobilized cells in flask cultures produced kojic acid in a linear proportion while maintaining the stable metabolic activity for a prolonged production period. kojic acid was accumulated up to a high concentration of 83 g/l, at which the kojic acid began to crystallize, and, thus, the culture had to be replaced with fresh media for the next batch culture. the over ...199218601027
three-dimensional phase-contrast imaging by a computed-tomography microscope.we report a technique for measuring the three-dimensional variation of refractive indices in a microscopic sample. the technique is an adaptation of optical computed tomography and is effective in measuring the three-dimensional refractive-index distribution of a nonabsorbing microscopic sample. our report also includes a discussion of the conditions for the unambiguous application of the technique as well as results of experiments conducted with aspergillus oryzae (commonly known as green mold) ...199220720664
effects of microorganisms on the peroxidation of lipid and fatty acid composition of fermented fish meal.fermentation of waste fish treated with aspergillus oryzae, aspergillus sojae k, and saccharomyces cerevisiae ifo 2114 were studied independently and combined. three microorganisms decreased the pov, mda, and coy of fish meal at different rates. the optimum conditions for fermentation with the combination of three microorganisms was found at 30°c for 20-hr fermentation. almost no difference was observed in the chemical composition or amino acid spectra of the protein hydrolysates of the fermente ...199227286377
preparation of activated supports containing low pk amino groups. a new tool for protein immobilization via the carboxyl coupling method.a method for the preparation of new aminated agarose gels containing monoaminoethyl-n-aminoethyl structures, mana-agarose gels, has been developed. these gels contain primary amino groups with a very low pk value (6.8). in addition to that, we have been able to prepare very highly activated gels (e.g., 10% agarose gels containing up to 200 mu eq of primary amines per milliliter). these two properties make these activated supports suitable for performing novel and interesting methods for protein ...19937763955
[occupational extrinsic allergic alveolitis due to aspergillus oryzae].we report a case of extrinsic allergic alveolitis, provoked by deterzyme, a product used in dermatology for the cleaning of cutaneous sores, and containing fractions of protolytic enzymes and amylases of aspergillus oryzae. the diagnosis was based on the positive precipitins to an extract of antigen of the product as well as positive bronchial provocation tests (semi-delayed) and the disappearance of the symptomatology without any sequelae following cessation of exposure to the risk.19937694333
cloning and nucleotide sequence of the acid protease-encoding gene (pepa) from aspergillus oryzae.we have cloned a genomic dna sequence encoding the acid protease (pepa) from aspergillus oryzae using a 0.6-kb fragment as a probe. this fragment was amplified by the polymerase chain reaction (pcr) using oligonucleotide primers designed from the partial amino acid sequences of peptide fragments of the purified protein. nucleotide sequencing analysis has shown that the cloned gene (designated pepa) encodes 404 amino acid residues and contains 3 putative introns ranging in length from 50 to 61 nu ...19937763981
borate ion-assisted stabilization of beta-galactosidase from aspergillus oryzae by polyhydroxy compounds in water-miscible organic solvents.the stability of beta-galactosidase from aspergillus oryzae in water-miscible organic solvents in different buffers at various ph values ranging from 4.6 to 8.0 was studied. the stability of the enzyme in all six organic solvents studied was dependent on ph and on the type of buffer ions present. at a given ph, destabilization by organic solvents was highest in sodium borate buffer. the destabilization of beta-galactosidase by these solvents could be reversed by addition of sugars or polyhydroxy ...19937764108
secretion of calf chymosin from the filamentous fungus aspergillus calf chymosin was secreted from aspergillus oryzae transformants when the chymosin cdna was expressed under the control of glucoamylase gene (glaa) promoter. secreted prochymosin was autocatalytically activated to the chymosin (0.07-0.16 mg/l). western blot analysis showed that a secreted protein immunoreactive with an anti-chymosin antibody was of similar size to authentic chymosin. northern blot analysis revealed that mrna of the chymosin cdna was expressed at as high level as that of t ...19937764387
production of a fungal protein, taka-amylase a, by protein-producing bacillus brevis expression-secretion vector, pmk300, was constructed to express the aspergillus oryzae taka-amylase a (taa) cdna. the promoter and signal peptide regions of the hwp (a major cell wall protein of bacillus brevis hpd31) gene on pmk300 were efficiently utilized in b. brevis hpd31 and a large amount of taa (22 mg/l) was secreted into the medium. the hwp signal peptide utilized for secretion of taa was correctly processed during the protein transport across the membrane. the enzymatic properties o ...19937763442
preparation and properties of rnase t1 immobilized on aminoethyl bio-gel p-2.the partially purified rnase t1, when coupled to glutaraldehyde activated aminoethyl bio-gel p-2, retained 22-24% activity of the soluble enzyme. immobilization resulted in an increase in the optimum temperature and temperature stability, but it did not affect the ph optimum. km and vmax decreased as a result of immobilization. the bound enzyme showed high stability to repeated use and storage.19937763565
characterization of immobilized enzymes in polyurethane foams in a dynamic bed reactor.beta-d-galactosidase (e from aspergillus oryzae was immobilized with polyurethane foam (puf). among several immobilization methods attempted in this work, the immobilized enzyme preparation by in-situ co-polymerization between enzyme and prepolymer hypol 3000 showed the highest activity. the intrinsic kinetics of puf-immobilized enzyme was determined in a dynamic bed reactor, used to increase transport rates. the immobilization mechanism in puf was studied by measurements of immobilize ...19937763711
miso from peas (pisum sativum) and beans (phaseolus vulgaris) of domestic origin. fermented foods from agricultural products in europe. ii.miso is a fermented soybean paste widely used in japan as a soup base or as a seasoning agent. koji (cereal grains with the mold aspergillus oryzae) serves as enzyme source. peas (pisum sativum) and beans (phaseolus vulgaris) of german origin can be used as substitutes for soybeans in the preparation of miso-like products. the legumes (peas, beans and soybeans for comparison) are washed, soaked in boiled water, dehulled and cooked for 35 min at reduced pressure. after grounding the seeds are mix ...19938237083
preparation, properties and application of aspergillus oryzae s1 nuclease covalently bound to aminobutyl-bio-gel p-2 through its carbohydrate moiety.purified aspergillus oryzae s1 nuclease, when covalently coupled to aminobutyl-(ab)-bio-gel p-2, via its carbohydrate moiety, retained 40-50% activity of the soluble enzyme. optimization of coupling conditions showed that the most active immobilized preparations are obtained when 50-60 units of 1 mm periodate-oxidized enzyme are allowed to react with 1 ml (packed volume) of ab-bio-gel p-2 at 4 degrees c, in the presence of 20% (v/v) ethylene glycol, for 15 h. immobilization did not change the ph ...19938338642
secondary structure and temperature-induced unfolding and refolding of ribonuclease t1 in aqueous solution. a fourier transform infrared spectroscopic study.the secondary structure of ribonuclease t1 (rnase t1) in aqueous solution and its temperature-induced structural changes have been investigated by fourier-transform infrared (ft-ir) spectroscopy. 13 to 14% alpha-helix and 32 to 33% beta-sheet were estimated from the resolution-enhanced ft-ir spectra, in agreement with the crystal structure which indicates 16% alpha-helix and 35% beta-sheet. specific ir-marker bands are assigned to the different beta-sheet structures, to the slightly bent alpha-h ...19938355280
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, ...19938359678
antibodies against active-site peptides common to glucosyltransferases of mutans streptococci.polyclonal antibodies were raised against peptides derived from an active-site sequence common to the family of mutans streptococcal glucosyltransferases (gtfs). the sequence contains an aspartic acid residue that functions in formation of the enzyme transition state in catalysis. two gtfs were targeted with similar but not identical sequences in this region: one that synthesizes an alpha-1,3-linked water-insoluble glucan and a homologous gtf that synthesizes an alpha-1,6-linked water-soluble gl ...19938406882
effect of nonfiber carbohydrate level and aspergillus oryzae fermentation extract on intake, digestion, and milk production in lactating dairy cows.eight multiparous, ruminally cannulated holstein cows averaging 40 d in milk and 575 kg bw at the start of trial were in a replicated 4 x 4 latin square arrangement (28-d periods) to determine the effects of dietary nonfiber carbohydrate (nfc) level and aspergillus oryzae fermentation extract (ao) on intake, milk production, and nutrient digestibility. treatments were 42 or 35% nfc and 0 or 3 g of ao per day arranged as a 2 x 2 factorial. diets formulated to contain 21% ndf from alfalfa silage ( ...19938386716
crystallization and x-ray diffraction analysis of recombinant coprinus cinereus peroxidase.crystals suitable for an x-ray diffraction investigation have been obtained of recombinant coprinus cinereus peroxidase expressed in aspergillus oryzae. the crystals were grown by the hanging drop method with polyethylene glycol 6000 as the precipitant. a ph range from 6.2 to 8.0 and cacl2 or mgcl2 present at a concentration of 0.35 m were essential for the crystal growth. a metastable monoclinic modification can be obtained under certain conditions, and with variations in temperature they are t ...19938394939
suicide-substrate inactivation of beta-galactosidase by diazomethyl beta-d-galactopyranosyl ketone.diazomethyl beta-d-galactopyranosyl ketone (1) has been proven to be a mechanism-based, irreversible (suicide-substrate) inactivator of aspergillus oryzae beta-d-galactosidase, but not an inactivator of e. coli lacz beta-d-galactosidase. compound 1 is stable in buffers of normal physiological ph. it is decomposed by h+, but not by nucleophiles. inactivation of a. oryzae beta-d-galactopyranosyl ketone (2) nor diazomethyl alpha-d-galactopyranosyl ketone inactivated the enzyme and therefore inactiv ...19938143286
studies on immobilization of aminoacylase on the functionalized polymethyl acrylate.functionalized polymethyl acrylate was used for the immobilization of aminoacylase of aspergillus oryzae. the effects of the degree of cross-linking, the amount of pore-forming agent and their mixing rates on the activity of immobilized aminoacylase were investigated. the results showed that the activity of the immobilized aminoacylase was the highest when the carrier was a combination of 20% cross-linking and 100% pore-forming agent. the effects of substrate concentration, ionic concentration, ...19938049353
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 ...19938462873
probiotics and manipulation of rumen development and function.there is good evidence that the bacterial and fungal probiotics are effective in the manipulation of rumen development and function. the effects of adherent streptococcus bovis preparations were manifested by significant increase of adherent s. bovis bacteria and alpha amylase activity in the rumen wall of young ruminants. fungal probiotics based on saccharomyces cerevisiae and aspergillus oryzae are rapidly gaining acceptance as a means of improving productivity in adult ruminants. however, fun ...19938215880
evidence for possible involvement of an elastolytic serine protease in aspergillosis.a number of isolates of aspergillus fumigatus obtained from the hospital environment produced extracellular elastolytic activity. this activity was found to be catalyzed by a single 33-kda protein which was purified and characterized to be a serine protease. a. fumigatus, when grown on the insoluble structural material obtained from murine and bovine lung, produced the same extracellular 33-kda elastolytic protease, indicating that this enzyme is likely to be produced when the organism infects t ...19938500876
effects of an aspergillus oryzae fermentation extract and other factors on lactate utilization by the ruminal bacterium megasphaera elsdenii.the objective of this study was to determine the effects of an aspergillus oryzae fermentation extract (amaferm) as well as other factors on lactate utilization by the ruminal bacterium megasphaera elsdenii b159. addition of amaferm or a filter-sterilized amaferm filtrate stimulated l-lactate uptake by both m. elsdenii and the ruminal selenomonad strain h18. growth of m. elsdenii in medium that contained dl-lactate (2 g/l), trypticase, and yeast extract was only slightly stimulated by the additi ...19938226379
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 ...19938370659
effect of aspergillus oryzae fermentation extract (amaferm) on in vitro fiber degradation.the influence of aspergillus oryzae fermentation extract (amaferm) on in vitro fiber degradation was determined by incubating eight ground fibrous feed-stuffs with rumen fluid and buffer inoculum. amaferm was added at 0, .4, .8, or 1.2 g/l of fermentation mixture. both ndf and adf degradabilities were determined after 96 h of incubation. addition of extract had no effect on ndf or adf degradability of pure cellulose, low endophyte fescue, wheat straw, corn silage, or prairie hay. addition of ama ...19938385163
decreased protein-stabilizing effects of cryoprotectants due to crystallization.the stabilizing effects of various additives against inactivation of an enzyme (beta-galactosidase from aspergillus oryzae) during freeze-drying were studied, with a focus on their crystallinity. the crystalline morphology of mannitol and inositol in freeze-dried cakes depended on the solute concentrations before freezing and the freeze-drying method used. the additives in their amorphous state showed concentration-dependent stabilization of the enzyme, whereas additive crystallization during fr ...19938415413
transition-state discrimination by adenosine deaminase from aspergillus oryzae.adenosine deaminase from aspergillus oryzae resembles mammalian adenosine deaminases in its ability to catalyze the hydrolytic removal of many substituents from c-6, and in the chirality at c-6 of the active isomer of the transition-state-analogue inhibitor 6-hydroxymethyl-1,6-dihydropurine ribonucleoside. the 5'-oh group of adenosine has been found to contribute a factor of 5.10(4) to transition-state stabilization by calf intestinal adenosine deaminase, and crystallographic observations sugges ...19938422418
stability of beta-galactosidase, a model protein drug, is related to water mobility as measured by 17o nuclear magnetic resonance (nmr).the inactivation of freeze-dried beta-galactosidase during storage was studied, focusing on the effect of water mobility as measured by the spin-lattice relaxation time, t1, of water using 17o nmr. inactivation of beta-galactosidase lyophilized from phosphate buffer solution was studied as a function of water content, which in turn affected the t1 of water. an increase in the water content of freeze-dried beta-galactosidase brought about an increase in the t1 of water, as well as a rise in ph. f ...19938430045
carbohydrate and aspergillus oryzae effects on intake, digestion, and milk production by dairy cows.six multiparous, ruminally cannulated holstein cows (46 dim, 584 kg of bw) and 6 primiparous holstein cows (35 dim, 506 kg of bw) were used in two 6 x 6 latin squares with 21-d periods to examine the effects of level of non-fiber carbohydrate, source of fibrous carbohydrate, and aspergillus oryzae fermentation extract on intake, digestion, and milk production. treatments were 42 and 36% non-fiber carbohydrate; shelled corn and soybean meal were replaced partially by beet pulp and dried brewers g ...19938436677
hypersensitivity pneumonitis in a soy sauce brewer caused by aspergillus oryzae. 19938436784
a structural domain (the lid) found in pancreatic lipases is absent in the guinea pig (phospho)lipase.typically pancreatic lipases are characterized by the following properties: (1) they are activated by lipid/water interfaces (interfacial activation), (2) they are inhibited by bile salts but reactivated by colipase (a small activator protein), and (3) they do not hydrolyze significantly phospholipids. a cdna clone encoding a guinea pig pancreatic (phospho)lipase (gpl) has been sequenced and expressed. the enzyme (recombinant as well as native) differs from other pancreatic lipases in that (1) i ...19938490016
expression of aspergillus oryzae alpha-amylase gene in saccharomyces cerevisiae.a fragment containing the full length cdna from aspergillus oryzae alpha-amylase has been amplified by pcr using specific synthetic oligonucleotides. the amplified cdna was designed to favour its expression in yeast by modifying its upstream untranslated region. it was subcloned in the expression vector pyex alpha 1, placed under the control of the yeast cyc1-gal10 promoter and used to transform saccharomyces cerevisiae. cells were then able to express and secrete active alpha-amylase to the med ...19938405943
aspergillus nidulans nuclear proteins bind to a ccaat element and the adjacent upstream sequence in the promoter region of the starch-inducible taka-amylase a gene.aspergillus nidulans was used as an intermediate host to investigate the regulation of the taka-amylase a (taa) gene from aspergillus oryzae. the induction of taa by starch was confirmed to be regulated at the transcriptional level by analyzing the transcripts specific for taa synthesized in vitro in nuclei from starch- and glucose-grown cells. a 55 bp dna fragment containing a consensus ccaat sequence from the promoter region of the taa gene was shown to confer starch inducibility on the gene. ...19938455560
crystals of beta-xylanase from aspergillus endo-xylanase was isolated from the culture of fungus aspergillus oryzae variant d5. the purified enzyme had a molecular weight of 24,000 and the isoelectric point of 3.6. xylanase crystals were obtained from a polyethylene glycol 6000 solution by the hanging-drop method. seeding was used for the enlargement of the crystal size. crystals belong to the monoclinic space group p2(1) with cell dimensions a = 54.9 a, b = 74.5 a, c = 50.8 a, and beta = 108.7 degrees. crystals diffract beyond 2.5 a ...19938464071
in vitro stimulation of forage fiber degradation by ruminal microorganisms with aspergillus oryzae fermentation extract.aspergillus oryzae fermentation extract (amaferm) was evaluated for its ability to influence degradation of brome grass and switchgrass fiber fractions by mixed ruminal microorganisms in vitro. addition of amaferm at a concentration of 0.067 mg/ml, which is approximately the concentration found in the rumen ecosystem (0.06 mg/ml), increased the degradation of brome grass neutral detergent fiber (ndf) by 28% after fermentation for 12 h (p < 0.01), but had no effect after fermentation for 24 or 48 ...199316349057
growth estimation of solid-state koji by covering a cellophane membrane on the a solid-substrate fermentation system, fungal growth within a solid mash is an important index for the efficiency of the saccharification and production of metabolites. estimation of fungal mass in such a heterogeneous solid-substrate systems is difficult and tedious. in this work, the comparison of aspergillus oryzae which is a common strain for the wine-brewing process cultured on a cellophane membrane placed on a koji juice agar medium and a small scale of steamed rice koji culture was con ...199314545687
characterization of an aspartic proteinase of mucor pusillus expressed in aspergillus oryzae.the aspartic proteinase (mpp) gene from the zygomycete fungus mucor pusillus was introduced into an ascomycete fungus, aspergillus oryzae, by protoplast transformation using the nitrate reductase (niad) gene as the selective marker. southern blot analysis indicated that the mpp gene was integrated into the resident niad locus at a copy number of 1-2. mpp secreted by the recombinant a. oryzae was correctly processed but was more highly glycosylated than that produced in the original m. pusillus s ...19938246885
the sequence and x-ray structure of the trypsin from fusarium oxysporum.the trypsin from fusarium oxysporum is equally homologous to trypsins from streptomyces griseus, streptomyces erythraeus and to bovine trypsin. a dfp (diisopropylfluorophosphate) inhibited form of the enzyme has been crystallized from 1.4 m na2so4, buffered with citrate at ph 5.0-5.5. the crystals belong to space group p2(1) with cell parameters a = 33.43 a, b = 67.65 a, c = 39.85 a and beta = 107.6 degrees. there is one protein molecule in the asymmetric unit. x-ray diffraction data to a resolu ...19938332590
influence of aspergillus oryzae fermentation extract on forage intake, site of digestion, in situ degradability, and duodenal amino acid flow in steers grazing cool-season pasture.ten ruminally and duodenally cannulated (326 +/- 28 kg) and four esophageally fistulated (394 +/- 23 kg) steers grazing cool-season pasture throughout the growing season were used to evaluate the influence of aspergillus oryzae fermentation extract (ao) supplementation on intake, forage nutrient utilization, and duodenal amino acid flow. steers grazed a predominantly smooth brome (bromus inermis l.) pasture, and measurements were taken in three periods (june, july, and august). steers were dosed ...19938385089
effects of aspergillus oryzae fermentation extract on in vitro equine cecal fermentation.the objective of this study was to examine the effects of aspergillus oryzae fermentation extract on the in vitro equine cecal fermentation of soluble starch, amino acids/peptides, coastal bermudagrass hay, and alfalfa hay. cecal contents were obtained from a cecally fistulated quarter horse gelding fed coastal bermudagrass and grain (70:30) either unadapted or adapted to dietary a. oryzae supplementation (2 g/d). mixed cecal microorganisms were incubated in anaerobic media for either 24 h (solu ...19938376241
energetics of ribonuclease t1 structure.the energetics of thermal denaturation of two isoforms of ribonuclease t1 (gln25 and lys25) in various solvents have been studied by differential scanning calorimetry. it has been shown that the thermal transition of both forms of rnase t1 is strongly affected by slow kinetics, which cause an apparent deviation of the transition from a simple two-state model. by decreasing the heating rate or increasing the transition temperature, the denaturation of rnase approaches an equilibrium two-state tra ...19948136367
response to various amounts of aspergillus oryzae fermentation extract on ruminal metabolism in cattle.the objective of this study was to determine whether aspergillus oryzae fermentation extract stimulated or inhibited ruminal fermentation when fed at higher than recommended doses (3 g/d). four dietary treatments of a. oryzae fermentation extract were fed daily to six cows fitted with ruminal cannulas. for each of four periods, bromegrass hay (6% cp) with and without extract was fed for 28 d. dacron bags containing bromegrass cell walls were ruminally incubated to determine ruminal fiber degrada ...19947836596
bakers' asthma caused by alpha amylase.two bakers with bronchial asthma and two with rhinoconjunctivitis are described. prick and rast tests were positive with wheat flour in all of them, but the challenge test (nasal or bronchial) with wheat flour extract was positive only in one asthmatic baker. the prick test, rast, and nasal or bronchial challenge done with alpha amylase extract (a glycolytic enzyme obtained from aspergillus oryzae and used as a flour additive) were positive in all four patients. our results support previous data ...19947944002
isolation and characterization of an aspergillus nidulans gene encoding an alkaline protease.we have cloned an aspergillus nidulans gene (prta) encoding an alkaline protease (alp) by probing an a. nidulans library with a fragment amplified from an aspergillus oryzae alp-encoding gene. the nucleotide (nt) sequence of prta was determined. the structure of prta is similar to that of the a. oryzae alp-encoding gene. the prta gene is composed of four exons which are separated by three introns of 59, 57 and 54 nt. the deduced amino acid sequence of the prta product shows a high degree of simi ...19947821793
filamentous fungi with high cytosolic phospholipid transfer activity in the presence of exogenous phospholipid.the phospholipid transfer activity of cell extracts from 15 filamentous fungus strains grown on a medium containing phospholipids as the carbon source was measured by a fluorescence assay. this assay was based on the transfer of pyrene-labeled phosphatidylcholines forming the donor vesicles to acceptor vesicles composed of egg phosphatidylcholines. the highest phosphatidylcholine transfer activity was obtained with cell extracts from aspergillus oryzae. the presence of exogenous phospholipids in ...199416349388
antioxidative effects of a processed grain food.antioxidant biofactor: aob is a unique processed grain food. it is a yellow-green powder. it contains the following extracts: germ extracts, soybean, rice bran, tear grass, sesame, wheat, citron, green tea, green leaf extract, and malted rice. these materials were slowly roasted under a powdered oure at less than 60 degrees c and fermented with aspergillus oryzae over 3 days to transform each ingredient into low molecular weight substances. these conditions were different by each material, envir ...19947891207
[are amylases in bakery products and flour potential food allergens?].the enzyme alpha-amylase from the mould aspergillus oryzae (asp o ii) routinely used for the production of bread, cakes and pastries has in recent years been identified as an inhalative allergen for occupational diseases (bakers' asthma). it is doubtful whether this amylase in the final product, i.e. after the baking procedure, can still be regarded as an allergen. to clarify this question, detailed case histories on 138 subjects were recorded (98 allergics, 20 patients suffering form chronic in ...19948209207
investigation of the functional interplay between the primary site and the subsite of rnase t1: kinetic analysis of single and multiple mutants for modified substrates.we report on the functional cooperativity of the primary site and the subsite of ribonuclease t1 (rnase t1; ec the kinetic properties of the single tyr-38-phe and asn-98-ala mutants have been compared with those of the corresponding double mutant. the tyr-38-phe mutation has been used to probe enzyme-substrate interactions at the primary site; the asn-98-ala mutation monitors subsite interactions. in addition to the dinucleoside phosphate substrate gpc, we measured the kinetics for gp ...19948208724
expression of apple 1-aminocyclopropane-1-carboxylate synthase in escherichia coli: kinetic characterization of wild-type and active-site mutant forms.the pyridoxal phosphate-dependent enzyme 1-aminocyclopropane-1-carboxylate synthase (acc synthase; s-adenosyl-l-methionine methylthioadenosine-lyase, ec catalyzes the conversion of s-adenosylmethionine (adomet) to acc and 5'-methylthioadenosine, the committed step in ethylene biosynthesis in plants. apple acc synthase was overexpressed in escherichia coli (3 mg/liter) and purified to near homogeneity. a continuous assay was developed by coupling the acc synthase reaction to the deamina ...19947809054
cloning and characterization of two structurally and functionally divergent rhamnogalacturonases from aspergillus aculeatus.two rhamnogalacturonases from the filamentous fungus aspergillus aculeatus have been cloned and characterized. a cdna library from a. aculeatus was constructed, and a novel rhamnogalacturonase b was isolated by expression cloning in yeast. for this purpose a new plate screening assay was developed, specific for the detection of rhamnogalacturonase activity. the rhamnogalacturonase a, known from previous reports, was shown not to be expressed in yeast in an active form. therefore, rhamnogalacturo ...19947961884
regioselective transglycosylation in the synthesis of oligosaccharides: comparison of beta-galactosidases and sialidases of various origins.n-acetyl-lactosamine(beta-d-gal p-(1-->4)-d-glc pnac) was synthesized regioselectively with the aid of the transglycosylation activity of beta-galactosidase isolated from diplococcus pneumoniae using p-nitrophenyl beta-d-galactopyranoside as the donor. also, transglycosylation of the sialyl group in an alpha-(2-->8)-linked sialic acid dimer or p-nitrophenyl glycoside of sialic acid to n-acetyl-lactosamine was performed using sialidases of various origins. when sialidase from clostridium perfring ...19948039189
effects of beet pulp and animal by-products on milk yield and in vitro fermentation by rumen microorganisms.forty-six holstein cows (30 primiparous) were assigned to one of four dietary treatments arranged as a 2 x 2 factorial experiment during wk 4 to 17 of lactation. main effects were corn versus dried sugar beet pulp and soybean meal versus animal by-product meal (mixture of meat and bone meal, feather meal, and blood meal). beet pulp replaced half of the corn at 15% of dietary dm. diet dm (mean of four treatments) contained 18% alfalfa pellets, 17.4% alfalfa hay, 17.2% corn silage, and 47.1% conce ...19948120188
regulatory circuits of the amds gene of aspergillus nidulans.the amds gene codes for an acetamidase enzyme that hydrolyses acetamide to acetate and ammonium thus providing a. nidulans with a source of carbon and nitrogen. the exceptionally favourable genetics of this system combined with molecular analysis have enabled many regulatory circuits affecting amds to be identified genetically. characterization of the regulatory genes and the definition of the cis-acting sites involved have been done using both in vivo and in vitro mutagenesis. recent results on ...19947847883
is stability prediction possible for protein drugs? denaturation kinetics of beta-galactosidase in solution.denaturation and aggregation kinetics of aspergillus oryzae beta-galactosidase in solution were studied in order to determine whether the stability of protein drugs can be predicted. denaturation of beta-galactosidase, monitored by measuring enzyme activity, conformed to first-order kinetics, whereas aggregation of the denatured form, monitored by high performance size exclusion chromatography, showed a reaction order higher than 1. denaturation of beta-galactosidase was irreversible and exhibit ...19947899234
influence of feeding aspergillus oryzae fermentation extract (amaferm) on in situ fiber degradation, ruminal fermentation, and microbial protein synthesis in nonlactating cows fed alfalfa or bromegrass hay.daily additions of 3 g of amaferm to alfalfa (13% cp) and bromegrass (6% cp) diets were evaluated for effects on ruminal and postruminal fiber and organic matter digestion, fermentation profile, and duodenal bacterial nitrogen flow. eight beef cows were fitted with ruminal and duodenal cannulas. two experiments were conducted. eight cows were fed bromegrass hay, four received amaferm and four served as controls; later, seven cows received alfalfa hay with three receiving amaferm and four serving ...19947928761
heat stress interactions with protein, supplemental fat, and fungal cultures.cows that were subjected to hot environmental temperatures yielded less milk (3.1 kg/d) on a diet high in cp (18.4%) and of medium degradability (65%) than on diets high in cp of low degradability (59%) or medium in cp (16.1%). the high cp diets were associated with decreased dmi and higher water intake, ruminal nh4, and blood urea. negative effects on yield from the high cp, medium degradability diet were not observed at moderate temperatures. evaporative cooling of cows in hot weather resulted ...19947929966
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 ...19948178442
an overview of the safety evaluation of the rhizomucor miehei lipase enzyme.the rhizomucor miehei lipase enzyme expressed in aspergillus oryzae, is used in the production of specialty fats, the production of existing fats from new raw materials, or new fats with improved nutritional or functional qualities. it is produced by a. oryzae containing the structural gene for the precursor of r. miehei triglyceride lipase. it was subjected to a series of toxicological tests to document the safety in use. the enzyme preparation was not found to be mutagenic either in bacterial ...19948181628
physical stability and protein stability of freeze-dried cakes during storage at elevated temperatures.the relationship between physical stability of freeze-dried cakes and protein stability during storage was studied using beta-galactosidase as a model protein and inositol as an excipient. amorphous samples freeze-dried from solutions containing the enzyme and various concentrations of inositol in sodium phosphate buffer (50 mm, ph 7.4) were stored for 7 days over p2o5 at 40 to 70 degrees c. structural collapse and inositol crystallization were observed in some of the samples, depending on the f ...19947937561
expression cloning, purification and characterization of a beta-1,4-mannanase from aspergillus aculeatus.a cdna library from the filamentous fungus aspergillus aculeatus was constructed in the yeast expression vector pyes2.0 and used to isolate 57 full length cdna's encoding beta-1,4-mannanase by expression in s. cerevisiae. the positive clones were identified on agar plates containing 0.2% azurine dyed cross-linked mannan by the formation of blue halos around the colonies. all clones represented transcripts of the same mannanase gene (man1). the gene was sub-cloned into an aspergillus expression v ...19947987261
enzymic synthesis of n-acetyllactosamine on a soluble, light-sensitive polymer. 19948004634
purification and properties of beta-fructofuranosidase from aspergillus oryzae atcc 76080.a fructooligosaccharide-producing beta-fructofuranosidase was purified from the crude extract of aspergillus oryzae atcc 76080 through successive steps of ultrafiltration, deae-sepharose cl-6b ion-exchange chromatography, preparative isoelectric focusing electrophoresis and sephacryl s-200 gel filtration. the purified enzyme had an optimal ph of 5-6, an optimal temperature of 50 degrees c, a km value of 0.53 m for catalyzing selftransfer reaction from sucrose. the molecular weight was 87 kda by ...19948019432
effect of ph during heat processing of partially hydrolyzed whey protein.whey protein isolate was modified by proteolysis using a broad-spectrum protease in combination with heat treatment of the hydrolysate. half of the beta-lactoglobulin content was hydrolyzed when the degree of hydrolysis reached 5.1%. alpha-lactalbumin and bsa were not attacked by the enzyme. heating of the hydrolysate resulted in the formation of small and large aggregates, the proportion of which depended on the degree of hydrolysis and the ph during heating. the decrease in total sulfhydryl gr ...19948169275
the gene amye(tv1) codes for a nonglucogenic alpha-amylase from thermoactinomyces vulgaris 94-2a in bacillus subtilis.we isolated the gene amye(tv1) from thermoactinomyces vulgaris 94-2a encoding a nonglucogenic alpha-amylase (amytv1). a chromosomal dna fragment of 2,247 bp contained an open reading frame of 483 codons, which was expressed in escherichia coli and bacillus subtilis. the deduced amino acid sequence of the amytv1 protein was confirmed by sequencing of several peptides derived from the enzyme isolated from a t. vulgaris 94-2a culture. the amino acid sequence was aligned with several known alpha-amy ...19947944369
biocompatibility of potential wound management products: fungal mycelia as a source of chitin/chitosan and their effect on the proliferation of human f1000 fibroblasts in culture.aspergillus oryzae, mucor mucedo, and phycomyces blakesleeanus cultures were examined as sources of chitin/chitosan. the nitrogen content of the alkali-treated mycelia/sporangiophores of a. oryzae, m. mucedo, and p. blakesleeanus was 2.52, 3.61, and 6.27% w/w, which relates to an estimated chitin content of 37, 52, and 91%, respectively. the effect of these fungal materials on the rate of proliferation of human f1000 fibroblasts in culture was examined. at 0.01% w/v, all three materials exhibite ...19948006051
[alpha-amylase as an occupational allergen in baking industry employees].in a group of 226 bakers and pastry makers and in 88 students of a training school for bakers, we evaluated skin sensitization to the common allergens, wheat and alpha amylase. skin prick tests were positive to the enzyme in 17 exposed subjects (7.5%) and in one student with previous occupational exposure as a baker; 27 exposed subjects (11.9%) and 2 students were sensitized to wheat. among the 42 exposed workers who complained of work-related symptoms, 12 (28.6%) cases were skin positive to amy ...19948072442
elucidation of the thermal stability of the neutral proteinase ii from aspergillus oryzae.the neutral proteinase ii from aspergillus oryzae (npii) is a zinc proteinase with three intramolecular disulfide bonds. npii is most unstable after 10 min at about 75 degrees c, but regains stability beyond this temperature and is relatively stable at 100 degrees c. we analyzed the thermal stability of wild-type npii and apo npii. the results suggested that npii unfolds reversibly upon incubation up to 100 degrees c, and that the irreversible inactivation observed is mainly due to autoproteolys ...19948086433
isolation and denomination of an important allergen in baking additives: alpha-amylase from aspergillus oryzae (asp o ii).the commercially available alpha-amylase from aspergillus oryzae which is widely used as a baking additive was compared with a highly purified enzyme preparation. we used enzyme allergosorbent test (east), east inhibition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page), isoelectric focussing, immunoblotting, and n-terminal amino acid sequencing to characterize the causative allergen. our screening comprised 89 partially selected bakers. forty-three (48%) of them had work-re ...19948087658
effect of yeast culture and aspergillus oryzae extract on milk yield in a commercial dairy herd.the objective of this study was to examine the effects of an aspergillus oryzae extract in combination with a yeast culture (saccharomyces cerevisiae) on milk yield and composition, rectal temperatures, and rumen parameters in a commercial dairy herd. pluriparous holstein cows (n = 521) in early lactation were assigned to a 130-d trial from may to september 1992. treatments were control (no additive) and yeast culture (56 g/d) plus a. oryzae (3 g/d). both groups were fed a tmr composed of alfalf ...19948120203
effect of mannitol crystallinity on the stabilization of enzymes during freeze-drying.the stabilizing effect of mannitol during the freeze-drying of proteins was studied using l-lactate dehydrogenase (ldh, rabbit muscle), beta-galactosidase (escherichia coli) and l-asparaginase (erwinia chrysanthemi) as model proteins. crystallization of mannitol was studied by powder x-ray diffraction and differential scanning calorimetry (dsc), in relation to the stabilizing effect. all the enzymes were protected concentration-dependently by amorphous mannitol, but the stabilizing effect was de ...19948124765
alpha-amylase hypersensitivity in non-exposed millers.occupational hypersensitivity to alpha-amylase among bakers and workers in the pharmaceutical industry has been described. we present the results of skin tests and in vitro methods used to assess alpha-amylase sensitivity in 259 millers. there was no occupational contact with the enzyme in this population. positive skin tests to this allergen were obtained in 16 subjects (6.18 per cent), specific ige values were found in seven subjects (2.7 per cent), specific igg was detected on 45 workers (17. ...19948032039
impact of point mutations on the structure and thermal stability of ribonuclease t1 in aqueous solution probed by fourier transform infrared spectroscopy.we undertook a detailed comparative analysis of the infrared spectra of wild-type ribonuclease t1 and three mutants: two single mutants, tyr-45-->trp (y45w) and trp-59-->tyr (w59y), and a double mutant, tyr-45-->trp/trp-59-->tyr (y45w/w59y). these mutants were selected because they are known to affect the activity of the enzyme. the structural differences were evaluated by using peptide backbone and side-chain "marker" bands as conformation-sensitive monitors. all mutations lead to a decrease of ...19948075073
serological responses induced in mice by immunogenic proteins and by protein respiratory is known that a variety of materials, including both low molecular weight chemicals and proteins, is able to induce occupational respiratory allergy. we have shown previously that exposure of mice to chemical respiratory sensitizers results in both a marked increase in the serum concentration of ige and the appearance of specific ige antibody. in the present study we have examined the characteristics of immune responses induced in mice following intraperitoneal exposure to 3 protein respirato ...19947518969
effect of various commercially available enzymes in the liquid chromatographic determination with external standardization of thiamine and riboflavin in foods.the efficacy of various commercially available enzymes in the determination of thiamine and riboflavin in foods was studied by liquid chromatography (lc) using external standards. different enzymes, as well as the same enzyme produced by different manufacturers, very strongly affected the determination of both vitamins. the recoveries for different foods ranged from 85 to over 100% for thiamine and from 80 to 100% for riboflavin. the present lc method was accurate and precise when tested on a fo ...19947516753
cloning and nucleotide sequence of the alkaline protease gene from fusarium sp. s-19-5 and expression in saccharomyces cerevisiae.we have cloned a genomic dna encoding the alkaline protease (alp) of fusarium sp. s-19-5 from a genomic dna library and sequenced the nucleotides. complementary dna encoding alp was also isolated from the cdna library after amplifying the gene by pcr using partial sequences of the alp genomic dna as primers. the alp gene has an open reading frame of 1137 nucleotides containing three introns. a tata box (taaata) was observed 112 base pairs upstream from the translation initiation codon in the 5'- ...19947764853
high level secretion of calf chymosin using a glucoamylase-prochymosin fusion gene in aspergillus oryzae.a recombinant chymosin was secreted at high levels using fusion genes with a. oryzae glucoamylase gene (glaa) and a wheat bran solid-state culture system. two portions of the a. oryzae glucoamylase, one with almost the entire glucoamylase (ga1-603) lacking 9 amino acids at the carboxyl terminal, and the other (ga1-511) lacking the starch binding-domain, were fused in frame with prochymosin cdna. western blot analysis indicated that the mature chymosin was released from the secreted fusion protei ...19947764977
glycosylation of glycoprotein 55 encoded by the anaemia-inducing strain of friend spleen focus-forming virus.normal rat kidney cells, non-productively infected with the anaemia-inducing variant of friend spleen focus-forming virus (f-sffva), were metabolically labelled with [2-3h]mannose. the primary translation product of the viral envelope gene (env), representing a glycoprotein with an apparent molecular m(r) of 55,000 (gp55), was isolated from cell lysates by immunoaffinity chromatography and purified by preparative sds/page. radiolabelled oligosaccharides, released from tryptic glycopeptides by tr ...19947804003
encapsulation of the thrombolytic enzyme, brinase, in photosensitized erythrocytes: a novel thrombolytic system based on photodynamic order to circumvent many of the problems associated with the systemic administration of agents used in thrombolytic therapy, it was decided to investigate the possibility of using erythrocytes as carriers and delivery vehicles for these agents. the enzyme brinase, a fibrinolytic enzyme produced by aspergillus oryzae, was loaded into rabbit erythrocytes using electroporation. the loading index for this enzyme was found to be 60% and incorporation appeared to be relatively stable over a period ...19947815192
a novel culture method for high level production of heterologous protein in saccharomyces cerevisiae.a high level production system for heterologous protein by cold culture of yeast transformants at 15 degrees c was developed. the yeast transformants, carrying a plasmid containing cdna for aspergillus oryzae alpha-amylase (taka-amylase a) or human lysozyme synthetic dna, were cultivated in a selective medium for 1 or 2 days until full growth at 30 degrees c. the yeast cells were harvested by centrifugation from the culture fluid and then were transferred to ypd medium. these inoculated broths w ...19947765252
chaperonin groe and adp facilitate the folding of various proteins and protect against heat the presence of adp, the molecular chaperones groel and groes from escherichia coli not only facilitated the refolding of various proteins, but also prevented their irreversible heat inactivation in vitro. without nucleotides the refolding reactions were arrested by groel. addition of groes and adp to the reaction mixture initiated the refolding reactions and the enzyme activities were regained efficiently. the presence of groe (groel and groes) and adp also protected against heat inactivatio ...19947911090
electrophoretic karyotype and gene assignment to chromosomes of aspergillus electrophoretic karyotype of aspergillus oryzae was obtained by transverse altering-field electrophoresis. seven chromosomal bands were found. with schizosaccharomyces pombe chromosomes as size standards, we estimated the sizes of the chromosomes to be 7.0, 5.2, 5.0, 4.5, 4.0, 3.7, and 2.8 megabase pairs (mbp). the chromosomal dna bands were identified with use of 13 cloned genes including ribosomal dna. the intensity of ethidium staining and the results of southern blotting with 100 random c ...19947765278
a dynamic light scattering study of beta-galactosidase: environmental effects on protein conformation and enzyme activity.dynamic light scattering (dls) is a useful technique for analyzing the size, shape, and other structural characteristics of protein molecules in solution. the effects of various environmental conditions on the structure and activity of aspergillus oryzae beta-galactosidase were studied. dls was used to determine protein particle size under various salt, ph, and temperature conditions. changes in the activity and stability of this enzyme caused by different environmental conditions were found to ...19947765378
[effect of cyclosporin on various metabolic processes in fungi].sensitivity of the representatives of aspergillus and piricularia to various concentrations of cyclosporine (in the submerged culture) was studied for choosing the test object for the subcellular investigation of the mechanism of the cyclosporine antifungal action. changes in the main physiological and biochemical parameters of the fungal cells under the action of cyclosporine in concentrations of 10 to 80 micrograms per 1 ml of the medium were characterized. low concentrations of cyclosporine ( ...19947840706
predicting fungal growth: the effect of water activity on aspergillus flavus and related species.growth of four species belonging to aspergillus section flavi (a. flavus, a. oryzae, a. parasiticus and a. nomius) was studied at 30 degrees c at ten water activities (aw) between 0.995 and 0.810 adjusted with equal mixtures of glucose and fructose. colony diameters were measured at intervals and plotted against time. a flexible growth model describing the change in colony diameter (mm) with respect to time was first fitted to the measured growth data and from the fitted curves the maximum colon ...19947873341
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 ...19948029213
increasing glutaminase activity in shoyu koji using a mixed culture of two koji moulds.for improved fermentation of shoyu (soy sauce), a useful koji-making system has been developed using a mixed tane-koji of two shoyu koji moulds, namely aspergillus oryzae k2 (length of conidiophores about 350 μm) and the late-conidiation strain, a. oryzae hg (length of conidiophores about 2500 μm). the mixed culture of strains k2 and hg had about twice the glutaminase activity of the single-strain cultures. in addition, the number of conidia in the mixed culture was about 10% of that in a cultur ...199424421198
oxygen fluorescence quenching studies with single tryptophan-containing proteins.the work of lakowicz and weber [biochemistry 12, 4161 (1973)] demonstrated that molecular oxygen is a powerful quencher of tryptophan fluorescence in proteins. here we report studies of the oxygen quenching of several proteins that have a single, internal tryptophan residue. among these are apoazurin (pseudomonas aeruginosa), asparaginase (escherichia coli), ribonuclease t1 (aspergillus oryzae), and cod parvalbumin. both fluorescence intensity and phase lifetime quenching data are reported. by c ...199424233381
the effect of urea on growth of moulds and biomass yield in solid-state cultivation.urea, added at 2 to 20 mg/g in solid bran medium supporting growth of aspergillus oryzae and rhizopus oligosporus, led to a higher concentration of nh4 (+) and ph but a decrease in biomass production.199524414664
reduction of cyanide levels in cassava during sequential sundrying and solid state fermentation.the cyanide levels were followed during protein enrichment of cassava by the fungus aspergilus oryzae. the total cyanogen level decreased by 158 mg/kg dry weight to 54.2 mg/kg dry weight as a result of the whole process including fermentation. the cyanogenic glucoside level decreased by 88% during the fermentation process while acetone cyanohydrin was retained in the cassava. the prefermentation processing which involved crushing, sundrying and milling the cassava into flour, reduced the total c ...19957712337
expression cloning, purification and characterization of a beta-1,4-galactanase from aspergillus aculeatus.expression cloning has been used to isolate a cdna encoding beta-1,4-galactanase from the filamentous fungus aspergillus aculeatus. a cdna library was prepared from mycelia, inserted in a yeast expression vector and transformed into saccharomyces cerevisiae. thirteen clones secreting galactanase activity were identified from a screening of approximately 2.5 x 10(4) yeast colonies. all clones expressed transcripts of the same galactanase gene. the cdna was re-cloned in an aspergillus expression v ...19957788716
stability of ribonuclease t2 from aspergillus oryzae.the stability of ribonuclease t2 (rnase t2) from aspergillus oryzae against guanidine hydrochloride and heat was studied by using cd and fluorescence. rnase t2 unfolded and refolded reversibly concomitant with activity, but the unfolding and refolding rates were very slow (order of hours). the free energy change for unfolding of rnase t2 in water was estimated to be 5.3 kcal.mol-1 at 25 degrees c by linear extrapolation method. from the thermal unfolding experiment in 20 mm sodium phosphate buff ...19957795525
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