Publications

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purification of s1 nuclease from aspergillus oryzae by recycling isoelectric focusing.we describe the purification of a single-strand nuclease from aspergillus oryzae using the first commercial prototype of an instrument (rf3tm) designed by milan bier et al. for preparative-scale isoelectric focusing. protein separation takes place entirely in solution, with shear-stabilized laminar flow counteracting convective disturbances generated by the electric field. conditions for isoelectric focusing were determined by focusing fractions with nuclease activity, following chromatography o ...19902079042
crystallographic characterization of wild-type and mutant ribonuclease t1 complexes with several ribonucleotides.ribonuclease t1 and the mutant enzymes were cocrystallized with several ribonucleotides, including non-hydrolyzable substrate analogs of di- and triribonucleotides, which have a novel guanylate in which the 2'-hydroxyl group of the ribose is replaced by a fluorine atom. one of the mutant enzymes has a tryptophan residue, instead of tyr45 of the wild-type enzyme, to enhance the binding of ribonucleotides to the enzyme and the other mutant enzyme has histidine and aspartate residues, instead of as ...19902081729
closely related glycosylation patterns of recombinant human il-2 expressed in a cho cell line and natural il-2.we report here the study of the glycosylation pattern of human recombinant (r) il2 expressed in a chinese hamster ovary (cho) cell line. the human ril2 secreted by this high-producing recombinant cho cell line was metabolically radiolabelled with [35s]-methionine, or with [3h]-glucosamine and [3h]-galactose, purified to homogeneity, and then characterized. the electrophoretic analysis of the [35s]-methionine-labelled proteins present in the culture medium of the cho cell line showed that the ril ...19902109157
ph dependence of the urea and guanidine hydrochloride denaturation of ribonuclease a and ribonuclease t1.to investigate the ph dependence of the conformational stability of ribonucleases a and t1, urea and guanidine hydrochloride denaturation curves have been determined over the ph range 2-10. the maximum conformational stability of both proteins is about 9 kcal/mol and occurs near ph 4.5 for ribonuclease t1 and between ph 7 and 9 for ribonuclease a. the ph dependence suggests that electrostatic interactions among the charged groups make a relatively small contribution to the conformational stabili ...19902110472
purification of recombinant ribonuclease t1 expressed in escherichia coli.a protocol for the rapid purification of ribonuclease t1 expressed from a chemically synthesized gene cloned into escherichia coli is described. qae ion-exchange and sephadex g-50 chromatography are used to give over 300 mg (88% yield) of pure ribonuclease t1 from 61 of liquid culture in 3 days. we also report a new absorption coefficient for rnase t1: e1%278 nm = 15.4.19902111835
purification of beta-galactosidase by combined frontal and displacement chromatography. 19902113370
active-site-directed inactivation of aspergillus oryzae beta-galactosidase with beta-d-galactopyranosylmethyl-p-nitrophenyltriazene.beta-d-galactopyranosylmethyl-p-nitrophenyltriazene (beta-galmnt), a specific inhibitor of beta-galactosidase, was isolated as crystals by hplc and its chemical and physicochemical characteristics were examined. aspergillus oryzae beta-galactosidase was inactivated by the compound. we studied the inhibition mechanism in detail. the inhibitor was hydrolyzed by the enzyme to p-nitroaniline and an active intermediate (beta-galactopyranosylmethyl carbonium or beta-galactopyranosylmethyldiazonium), w ...19902113523
replacement of a cis proline simplifies the mechanism of ribonuclease t1 folding.the refolding of ribonuclease t1 is dominated by two major slow kinetic phases that show properties of proline isomerization reactions. we report here that the molecular origin of one of these processes is the trans----cis isomerization of the ser54-pro55 peptide bond, which is cis in the native protein but predominantly trans in unfolded ribonuclease t1. this is shown by a comparison of the wild type and a designed mutant protein where ser54 and pro55 were replaced by gly54 and asn55, respectiv ...19902119802
primary structure of the oligo-1,6-glucosidase of bacillus cereus atcc7064 deduced from the nucleotide sequence of the cloned gene.the gene coding for bacillus cereus atcc7064 (mesophile) oligo-1,6-glucosidase was cloned within a 2.8-kb sali-ecori fragment of dna, using the plasmid puc19 as a vector and escherichia coli c600 as a host. e. coli c600 bearing the hybrid plasmid pbce4 accumulated oligo-1,6-glucosidase in the cytoplasm. the cloned enzyme coincided absolutely with b. cereus oligo-1,6-glucosidase in its mr (65,000), in its electrophoretic behavior on a polyacrylamide gel with or without sodium dodecyl sulfate, in ...19902120057
crystallization and preliminary x-ray investigation of non-specific complexes of a mutant ribonuclease t1 (y45w) with 2'amp and 2'ump.we have succeeded in crystallizing complexes of a mutant ribonuclease t1 (y45w) with the non-cognizable ribonucleotides 2'amp and 2'ump by macroscopic seeding of microcrystals of the mutant enzyme complexed with 2'gmp, which is the cognizable nucleotide inhibitor. the mutant enzyme has a tryptophan residue instead of tyr45 of the wild-type enzyme and thus this mutation enhances the binding of ribonucleotides to the enzyme. the space group is p212121 with unit cell dimensions a = 49.40 a, b = 46. ...19902124272
hypocholesterolemic effect of the undigested fraction of soy protein. 19902126604
asperfuran, a novel antifungal metabolite from aspergillus oryzae.asperfuran is a novel antifungal dihydrobenzofuran derivative produced by a strain of aspergillus oryzae. asperfuran weakly inhibited chitin synthase from coprinus cinereus. this inhibition could be abolished by the addition of egg lecithin. in the agar diffusion assay asperfuran induced morphological changes in mucor miehei at very low concentrations (20 ng/disc) while growth was only partly inhibited. in hela s3 and l1210 cells it showed weak cytotoxicity, the ic50 was 25 micrograms/ml.19902143181
calculation of the relative binding free energy of 2'gmp and 2'amp to ribonuclease t1 using molecular dynamics/free energy perturbation approaches.we present a calculation of the relative changes in binding free energy between the complex of ribonuclease t1 (rnase tr) with its inhibitor 2'-guanosine monophosphate (2'gmp) and that of rnase t1-2'-adenosine monophosphate (2'amp) by means of a thermodynamic perturbation method implemented with molecular dynamics. using the available crystal structure of the rnase t1-2'gmp complex, the structure of the rnase t1-2'amp complex was obtained as a final structure of the perturbation calculation. the ...19902157020
calcium binding in alpha-amylases: an x-ray diffraction study at 2.1-a resolution of two enzymes from aspergillus.x-ray diffraction analysis (at 2.1-a resolution) of an acid alpha-amylase from aspergillus niger allowed a detailed description of the stereochemistry of the calcium-binding sites. the primary site (which is essential in maintaining proper folding around the active site) contains a tightly bound ca2+ with an unusually high number of eight ligands (o delta 1 and o delta 2 of asp175, o delta of asn121, main-chain carbonyl oxygens of glu162 and glu210, and three water molecules). a secondary bindin ...19902207069
primary structure of a base non-specific and adenylic acid preferential ribonuclease from aspergillus saitoi.the complete primary structure of a base non-specific and adenylic acid preferential rnase (rnase m) from aspergillus saitoi was determined. the sequence was determined by analysis of the peptides generated by digestion of heat-denatured rnase m with lysylendopeptidase, and the peptides generated from rcm rnase m by digestion with staphylococcal v8 protease or chemical cleavage with brcn. it consisted of 238 amino acid residues and carbohydrate moiety attached to the 74th asparagine residue. the ...19902229029
effects of feeding fungal culture extract and animal-vegetable fat on degradation of hemicellulose and on ruminal bacterial growth in heifers.four holstein heifers cannulated in the rumen and proximal duodenum were used to analyze effects of aspergillus oryzae fermentation extract and yeast culture (amaferm micro-mix. biozyme enterprises, inc., st. joseph, mo) and 5% animal-vegetable fat on ruminal and total tract digestibilities of nutrients. heifers were assigned treatments in a 4 x 4 latin square design with a 2 x 2 factorial arrangement of treatments. few interactions between main effects were noted. feeding fat decreased ruminal ...19902229593
a case of occupational allergic bronchopulmonary aspergillosis unique to japan.a 15-year-old female was diagnosed in 1980 as having allergic bronchopulmonary aspergillosis (abpa) due to aspergillus fumigatus based on rosenberg and patterson's criteria for the disease. the patient is the eldest daughter of a family of domestic brewers of soy sauce and bean paste in a small village, an occupation unique to japan. the brewing process involved the use of aspergillus oryzae as a fermenting agent. the patient had experienced episodic wheezing and pulmonary infiltrates during the ...19902282302
effect of feeding aspergillus oryzae fermentation extract or aspergillus oryzae plus yeast culture plus mineral and vitamin supplement on performance of holstein cows during a complete lactation.the addition of aspergillus oryzae fermentation extract (amaferm) increased milk flow and mean 3.5% fcm production during the latter stages of the full lactation trial compared with the control group and the aspergillus oryzae fermentation extract plus yeast culture plus mineral-vitamin supplement (vitaferm) group. based on the differences observed when fcm production was determined for the cows at various stages of lactation, amaferm apparently had its greatest effect during the early stages of ...19902283420
identification of two essential histidine residues of ribonuclease t2 from aspergillus oryzae.ribonuclease (rnase) t2 from aspergillus oryzae was modified by diethyl pyrocarbonate and iodoacetic acid. rnase t2 was rapidly inactivated by diethyl pyrocarbonate above ph 6.0 and by incorporation of a carboxymethyl group. no inactivation occurred in the presence of 3'amp. 1h-nmr titration and photo-chemically induced dynamic nuclear polarization experiments demonstrated that two histidine residues were involved in the active site of rnase t2. furthermore, analysis of inactive carboxymethylate ...19902298207
conserved residues of liquefying alpha-amylases are concentrated in the vicinity of active site.three dimensional structure of three liquefying type bacillus alpha-amylases were modeled based on sequence analyses and refined structure of aspergillus oryzae enzyme. the models suggest that the overall folding motif of alpha-amylases is conserved. the active site, substrate binding and stabilizing calcium binding residues are conserved and concentrated in a cleft between two domains. they constitute the core of alpha-amylases to which other, less conserved regions are attached. the bacterial ...19902302216
simultaneous comparison of several sequences. 19902314287
[baking ingredients, especially alpha-amylase, as occupational inhalation allergens in the baking industry].baker's asthma is the most frequent occupational lung disease in switzerland and west germany. cereal flours, and more rarely flour parasites, are implicated as the responsible allergens. based on an observation of a case of baker's asthma due to monovalent sensitization to alpha-amylase used as additive to flour, 31 bakers with occupational asthma and/or rhinitis were routinely tested by skin tests and serological rast examinations for allergic sensitivity to flour, alpha-amylase and other bake ...19902326614
influence of cultures of aspergillus oryzae on rumen and total tract digestibility of dietary components.three trials were conducted to evaluate the effect of dried cultures of aspergillus oryzae on nutrient utilization by mature holstein cows fitted with ruminal and duodenal cannulas. in trial 1, four cows (two dry and two lactating) were used to test aspergillus oryzae (3 g/d) and a control treatment at two forage amounts in a 4 x 4 latin square. trial 2 compared control, a. oryzae, and saccharomyces cerevesiae using six lactating cows in a repeated 3 x 3 latin square design. for trial 3, four la ...19902341646
localization of pyruvate carboxylase in organic acid-producing aspergillus strains.the localization of pyruvate carboxylase (cytosolic or mitochondrial) was studied in nine different aspergillus species (14 strains). in some species (a. aculeatus, a. flavus, a. foetidus, a. nidulans, a. ochraceus, and a. sojae), the pyruvate carboxylase activity could be detected only in the cytosolic fraction of the cells. pyruvate carboxylase has been found only in the mitochondrial fraction of two strains of aspergillus wentii. in aspergillus oryzae and in five strains of aspergillus niger, ...19902383004
characteristics of immobilized aminoacylase from aspergillus oryzae on macroporous copolymers.aminoacylase from aspergillus oryzae was adsorbed on functionallized macroporous copolymers where the enzyme showed excellent catalyzing activity and operation stability. various factors which effect the activity of the immobilized aminoacylase such as temperature, ph and ionic strength were investigated. the continuous operation of the enzyme immobilized on macroporous copolymers was compared with that of the enzyme immobilized on deae-sephadex.19902383665
calorimetric analysis of microbial growth: with special reference to quantitative evaluation of drug action.our research method for the calorimetric characterization of the biological effects of drugs and other chemicals on metabolic activities of living cells is outlined. the effects of various substances on different microbial systems were studied quantitatively using a calorimeter, and the results were used to plot drug potency curves for each drug. the method was also used to study microbial activity in soil. it was found to be a useful technique for the quantitative characterization of pollutants ...19901966694
secretion of aspergillus oryzae alkaline protease in an osmophilic yeast, zygosaccharomyces rouxii.to produce aspergillus oryzae alkaline protease (alp) in an osmophilic yeast zygosaccharomyces rouxii, we constructed an expression plasmid consisting of the z. rouxii glyceraldehyde-3-phosphate dehydrogenase (gapdh) promoter, the prepro-alp cdna of a. oryzae, the whole sequence of z. rouxii plasmid psr1, and the g418 resistant gene. the resulting plasmid, when introduced into z. rouxii cells, directed the secretion of a large amount (about 300 mg/l) of alp into the culture medium. the n-terminu ...19901369295
effects of aspergillus oryzae fermentation extract on fermentation of amino acids, bermudagrass and starch by mixed ruminal microorganisms in vitro.the objective of this study was to examine the effects of aspergillus oryzae fermentation extract (amaferm) on the in vitro ruminal fermentation of coastal bermudagrass, soluble starch and amino acids. mixed ruminal microorganisms were incubated in anaerobic media for either 24 h (amaferm alone, soluble starch, amino acids) or 48 h (bermudagrass). amaferm was added to the incubation bottles (n = 4) at concentrations of 0, .4 or 1.0 g/liter. when mixed ruminal microorganisms were incubated with o ...19902384404
effect of dicarboxylic acids and aspergillus oryzae fermentation extract on lactate uptake by the ruminal bacterium selenomonas ruminantium.the objective of this study was to determine the effects of l-aspartate, fumarate, l-malate, and an aspergillus oryzae fermentation extract (amaferm) on growth on lactate as well as lactate uptake by selenomonas ruminantium hd4. growth of s. ruminantium in medium that contained 2 g of dl-lactate per liter was stimulated approximately twofold by 10 mm l-aspartate, fumarate, or l-malate after 24 h. both l-aspartate and fumarate increased lactate uptake over 4-fold, while l-malate stimulated uptake ...199016348354
action pattern of alpha-amylase from aspergillus oryzae in concentrated media.the influence of concentrated maltotetraose solutions on fungal alpha-amylase activity and specificity has been determined. it has been found that the enzyme is not inhibited by 500 g/l substrate concentration and that transglycosylation reactions are increased with rising substrate concentration. the amount of oligosaccharides of polymerization degree higher than maltotetraose reaches 20% (w/w). moreover, the effect of polyhydric alcohols, known as water activity depressors has been analyzed: t ...199018592604
use of novel immobilized beta-galactosidase reactor to hydrolyze the lactose constituent of skim milk.beta-galactosidase from aspergillus oryzae immobilized in an axial-annular flow reactor was used to effect the hydrolysis of the lactose component of skim milk. nonlinear regression methods were employed to determine the kinetic parameters of four rate expressions derived from a proposed enzymatic mechanism. data taken at three different temperatures (30 degrees c, 40 degrees c, and 50 degrees c) were fit via nonlinear regression methods assuming an arrhenius temperature model for each of the pa ...199018595081
hydrolysis of lactose in skim milk by immobilized beta-galactosidase in a spiral flow reactor.beta-galactosidase from aspergillus oryzae immobilized in a spiral flow reactor was used to effect the hydrolysis of the lactose component of skim milk. residence time distribution measurements were used to assess the amount of longitudinal dispersion occurring as a consequence of the spiral flow pattern and the semiporous nature of the polymeric material used to construct the spiral. it was possible to model the flow conditions as tubular flow with a peclet number that was a linear function of ...198918587857
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 ...19892489084
enzyme replacement for lactose malabsorption using a beta-d-galactosidase.we evaluated 10 healthy symptomatic lactose malabsorbers for effect of an oral beta-d-galactosidase derived from aspergillus oryzae (lactrase, kremers urban company, milwaukee, wi, u.s.a.) on symptom and breath hydrogen response to challenge with 50 g lactose. basally and at 30-min intervals for 8 h after lactose challenge, end-alveolar breath samples were collected and analyzed for hydrogen using gas chromatography. symptoms were scored at 30 min and hourly for 8 h, rating bloating, cramps, nau ...19892502573
binding of vanadate (v) to ribonuclease-t1 and inosine, investigated by 51v nmr spectroscopy.ribonuclease t1 (rnase-t1) from aspergillus oryzae cleaves ribonucleic acid specifically at guanosine to yield oligonucleotides with terminal guanosine-3'-phosphate. it forms a complex with vanadate (association constant k approximately 145 +/- 30 m-1; delta (51v) = -514 ppm) with spectral features similar to the less stable complexes obtained with di- and tripeptides (gly-his, pros-his-ala, gly-his-lys, val-glu) containing amino acids that are constituents at the active site of the enzyme. guan ...19892513377
synergistic antifungal action of 8-quinolinol and its bischelate with copper(ii) and with mixed ligand chelates composed of copper(ii), 8-quinolinol, and aromatic hydroxy acids.antifungal studies were made of mixtures of minimal inhibitory concentrations (mics) of 8-quinolinol and its bischelates with copper(ii), zinc(ii), and manganese(ii) and with mixed ligand chelates composed of 8-quinolinol, copper(ii) and a second ligand including salicylic acid, 3-hydroxy-2-naphthoic acid, 3,5-diiodosalicylic acid, and 4-bromo-3-hydroxy-2-naphthoic acid. mixtures of the mics of the bischelates of 8-quinolinol with copper(ii) and zinc(ii) and copper(ii) and manganese(ii), as well ...19892516124
three-dimensional structure of ribonuclease t1 complexed with guanylyl-2',5'-guanosine at 1.8 a resolution.the enzyme ribonuclease t1 (rnase t1) isolated from aspergillus oryzae was cocrystallized with the specific inhibitor guanylyl-2',5'-guanosine (2',5'-gpg) and the structure refined by the stereochemically restrained least-squares refinement method to a crystallographic r-factor of 14.9% for x-ray data above 3 sigma in the resolution range 6 to 1.8 a. the refined model consists of 781 protein atoms, 43 inhibitor atoms in a major site and 29 inhibitor atoms in a minor site, 107 water oxygen atoms, ...19892541256
rhizomucor miehei triglyceride lipase is processed and secreted from transformed aspergillus oryzae.the cdna encoding the precursor of the rhizomucor miehei triglyceride lipase was inserted in an aspergillus oryzae expression vector. in this vector the expression of the lipase cdna is under control of the aspergillus oryzae alpha-amylase gene promoter and the aspergillus niger glucoamylase gene terminator. the recombinant plasmid was introduced into aspergillus oryzae, and transformed colonies were selected and screened for lipase expression. lipase-positive transformants were grown in a small ...19892586234
[the stimulating effect of n-nitroso-ethylurea on the biosynthetic ability of aspergillus oryzae].the mutagenic action of n-nitroso-n-ethylurea (neu) taken at shock and prolonged doses together on aspergillus oryzae yielded 98% of populations with an elevated synthesis of proteolytic enzymes. the combined action of shock and prolonged neu doses had an advantage over a shock pulse dose because the frequency of mutations rose 2-16 times and the populations accumulated proteolytic enzymes within the range of 9 to 24 activity units. as was shown using a certain number of populations selected at ...19892586348
preparation and properties of rnase t2 immobilized on concanavalin a-sepharose.partially purified rnase t2 (ec 2.7.7.17) from aspergillus oryzae was bound through its carbohydrate moiety to concanavalin a-sepharose. the retention of activity was high, ranging from 70% at low enzyme load to approximately 9% at high enzyme load. though there was no change in the ph and temperature optima, the ph stability and the km decreased after immobilization. compared to the soluble enzyme, the immobilized rnase t2 showed enhanced temperature stability and more resistance to metal ions. ...19892596845
purification and characterization of an insect alpha-amylase inhibitor/endochitinase from seeds of job's tears (coix lachryma-jobi).a protein inhibitor of locust gut alpha-amylase was purified from seeds of job's tears (coix lachryma-jobi) using ammonium sulphate precipitation, affinity chromatography on red sepharose and reversed-phase hplc. it consisted of two major isomers, each a dimer of two closely similar or identical subunits of mr about 26,400, and associated by inter-chain disulphide bonds. these isomers also had closely similar amino acid compositions. the major isomer showed no inhibitory activity against amylase ...19892605263
isolation of a cdna encoding aspergillus oryzae taka-amylase a: evidence for multiple related genes.complementary and genomic dnas encoding aspergillus oryzae taka-amylase a (taa) were cloned and sequenced. the coding sequence of the cdna comprised the signal peptide [21 amino acids (aa)] and mature taa (478 aa). the deduced aa sequence agrees well with the published aa sequence, except for one insertion, one deletion and ten aa substitutions. these differences might be due to the difference in the strains used. sequence comparison of the cdna and genomic dna indicates the presence of eight in ...19892612911
characterization of three enzymatic forms of glucose-6-phosphate dehydrogenase from aspergillus oryzae.three forms (i, ii and iii) of glucose-6-phosphate dehydrogenase were isolated from mycelium of aspergillus oryzae grown on ribose as the carbon source, by ion-exchange chromatography. the km values determined for the three forms with respect to glucose-6-phosphate were nearly identical; however the km for nadp+ were different and the vmax for the isoenzymatic form ii was higher than those for i and iii. inhibition by nadph was competitive with respect to nadp+, isoenzyme ii showing the highest ...19892616874
probing the anticodon loop structure in yeast trna(phe-y) with single strand-specific nuclease s1.yeast trna(phe) and trna(phe-y) are cleaved by single strand-specific endonuclease s1 at the same positions within the anticodon loop (phosphates 34, 36 and 37) and at the 3'-terminus (phosphates 75 and 76). the efficiency of the anticodon loop hydrolysis is much higher in trna(phe-y) while the cutting at the 3'-terminus is not influenced considerably by the y-base1 removal from yeast trna(phe). the effect of the y-base excision on the structure of the anticodon loop is discussed on the basis of ...19892618244
free flow electrophoresis as a method for the purification of enzymes from e. coli cell extract.the application of the four techniques of free flow electrophoresis (zone electrophoresis, isotachophoresis, isoelectric focusing and field step electrophoresis) for the purification of proteins from a complex protein mixture was investigated. for this purpose alpha-amylase (ec 3.2.1.1) from aspergillus oryzae was added and reisolated from e. coli cell extract. the chosen enzyme and the biological extract are models for many industrial separation problems. in optimized experiments purity, purifi ...19892651110
conformational stability and activity of ribonuclease t1 and mutants. gln25----lys, glu58----ala, and the double mutant.ribonuclease t1 (rnase t1) and mutants gln25----lys, glu58----ala, and the double mutant were prepared from a chemically synthesized gene, cloned and expressed in escherichia coli. the wild-type rnase t1 prepared from the cloned gene was identical in every functional and physical property examined to rnase t1 prepared from aspergillus oryzae. urea and thermal unfolding experiments show that gln25----lys is 0.9 kcal/mol more stable and glu58----ala is 0.8 kcal/mol less stable than wild-type rnase ...19892663837
a gene transfer system based on the homologous pyrg gene and efficient expression of bacterial genes in aspergillus oryzae.a homologous transformation system for aspergillus oryzae is described. the system is based on an a. oryzae strain deficient in orotidine-5'-phosphate decarboxylase (pyrg) and the vector pao4-2, which contains a functional a. oryzae pyrg gene as selection marker. transformation of the a. oryzae pyrg mutant with circular pao4-2 resulted in the appearance of pyr+ transformants at a frequency of up to 20 per micrograms of dna, whereas with linear pao4-2 up to 200 transformants per micrograms dna we ...19892688930
a full length cdna clone for the alkaline protease from aspergillus oryzae: structural analysis and expression in saccharomyces cerevisiae.we have cloned and determined the nucleotide sequence of a cdna fragment for the entire coding region of the alkaline protease (alp) from a filamentous ascomycete aspergillus oryzae. according to the deduced amino acid sequence, alp has a putative prepro region of 121 amino acids preceding the mature region, which consists of 282 amino acids. a consensus sequence of a signal peptide consisting of 21 amino acids is found at the n-terminus of the prepro region. the primary structure of the mature ...19892693947
studies on the accessibility of nascent non-helical peptide chains on the ribosome.the accessibility of nascent polypeptides with special structural elements to the ribosome was investigated. poly(c), poly(c, u) and poly(c, a) mrnas were translated by e. coli ribosomes in vitro. the resulting peptides which were rich in prolines, remained on the ribosomal particles or were released after addition of puromycin. a protease from aspergillus oryzae hydrolyzed the released peptides rapidly, whereas the degradation of the unreleased ones was only slightly affected. this result shows ...19892699792
three alpha-amylase genes of aspergillus oryzae exhibit identical intron-exon organization.we have cloned three genes (amy1, amy2 and amy3) encoding alpha-amylase in the filamentous fungus aspergillus oryzae. the established overall sequences have a very high degree of homology, showing divergences mainly in the 3'-untranslated regions. the positions and the sequences of the eight introns were found to be absolutely identical in the three genes. the sequence analysis of the 5'-regions revealed presumptive tata, caat and gc boxes. primer extension analysis was performed to determine th ...19892785629
aspergillus oryzae has two nearly identical taka-amylase genes, each containing eight introns.cdna and genomic dna for two nearly identical genes, amyi and amyii, coding for the enzyme taka-amylase a (ta-a) of the fungus aspergillus oryzae have been cloned and characterized. these genes are apparently unlinked, differing by only 3 nucleotides (nt) out of the 2720 nt that span the coding regions. the 617-nt 5'-flanking regions differ only at nt -372 (t or a) from the putative atg start codon and contain four sets of short, inverted repeats (ir) upstream from the putative tataaa box at nt ...19892789162
studies on antifungal properties of phenol complexes with secondary amines. 1. the effect of complex formation of nitro- and chlorophenols with dicyclohexylamine on the antifungal activity in vitro.inhibitory doses (id50) of phenols complexed with dicyclohexylamine are lower (21.4-47.7%) than the inhibitory doses of free phenols. this is demonstrated in vitro by experiments with aspergillus oryzae and penicillium expansum on solid medium.19892797052
analysis of the alpha-amylase gene of schwanniomyces occidentalis and the secretion of its gene product in transformants of different yeast genera.we have cloned and characterized the alpha-amylase gene (amy1) of the yeast schwanniomyces occidentalis. a cosmid gene library of s. occidentalis dna was screened in saccharomyces cerevisiae for alpha-amylase secretion. the positive clone contained a dna fragment harbouring an open reading frame of 1536 nucleotides coding for a 512-amino-acid polypeptide with a calculated mr of 56,500. the deduced amino acid sequence reveals significant similarity to the sequence of the saccharomycopsis fibulige ...19892806251
properties of the complex between alpha 2-macroglobulin and brinase, a proteinase from aspergillus oryzae with thrombolytic effect.the proteinase, brinase (mr approximately 35000), from aspergillus oryzae, which has been used in therapeutic attempts as a thrombolytic agent in arterial thrombosis, binds to purified human alpha 2-macroglobulin (alpha 2m) with a stoichiometry of 1.7-1.9 mol of enzyme/mol inhibitor. this binding leads to quantitative cleavage of the bait region of the inhibitor and to release of 3.6 thiol groups per molecule of alpha 2m, reflecting cleavage of the thioester bonds. the reaction with brinase is a ...19882450410
conformational stability and activity of ribonuclease t1 with zero, one, and two intact disulfide bonds.ribonuclease t1 has two disulfide bonds linking cysteine residues 2-10 and 6-103. we have prepared a derivative of ribonuclease t1 in which one disulfide bond is broken and the cysteine residues carboxymethylated, (2-10)-rcm-t1, and three derivatives in which both disulfides are broken and the cysteine residues reduced, r-t1, carboxamidomethylated, rcam-t1, or carboxymethylated, rcm-t1. the rna hydrolyzing activity of these proteins has been measured, and urea and thermal denaturation studies ha ...19882457027
biosynthesis, in calf pancreas microsomes, of three lipid-linked oligosaccharide diphosphates from a synthetic dolichyl diphosphate tetrasaccharide.incubation of calf pancreas microsomes with synthetic alpha-d-manp-(1----6)-beta-d-manp-(1----4)-beta-d-glcpnac-(1 ----4)-alpha-d- glcpnac-pp-dol and gdp-d-[14c]-mannose gave three major lipid-linked oligosaccharide diphosphates. after release of the phospholipid residue by mild acid hydrolysis, the corresponding [14c]oligosaccharides were analyzed by gel-filtration, liquid chromatography, degradation by endo-n-acetyl-beta-d-glucosaminidases d and h, by jack bean alpha-d-mannosidase and aspergil ...19882463085
action of gamma endonuclease on clustered lesions in irradiated dna.irradiation of dna in situ i.e. in phage particles or in the cell leads to alterations of single dna nucleotides as well as to clustered lesions such as double strand breaks or unpaired dna regions the latter being sensitive to digestion by s1 nuclease. a contribution will be made to the configuration of such s1-nuclease-sensitive sites (s1 sites). dna from irradiated lambda phage containing s1 sites was treated with gamma endonuclease from m. luteus which is known to split the nucleotide strand ...19882839862
1h-nmr investigation of the interaction between rnase t1 and a novel substrate analog, 2'-deoxy-2'-fluoroguanylyl-(3'-5')uridine.the interaction between rnase t1 and a non-hydrolysable substrate analog, 2'-deoxy-2'-fluoroguanylyl-(3'-5')uridine (gfpu), was investigated using 1h-nmr spectroscopy. in the complex, the gfp portion takes the syn form around the glycosidic bond and the 3'-endo form for the ribose moiety, similar to those found in 3'-gmp and 2'-deoxy-2'-fluoroguanosine 3'-monophosphate (gfp). however, in contrast to the cases of these two inhibitors, the complex formation with gfpu at ph 6.0 was found to shift t ...19882841155
jokichi takamine (1854-1922). 19883057095
expression of the chemically synthesized gene for ribonuclease t1 in escherichia coli using a secretion cloning vector.the gene for ribonuclease t1 from aspergillus oryzae has been chemically synthesized using the segmental support technique. an escherichia coli clone producing the ribonuclease at high levels was constructed by linking the gene downstream to the region coding for the signal peptide of the ompa protein (a major outer membrane protein of e. coli), using the secretion cloning vector pin-iii-ompa2. this strategy was employed in order to circumvent a possible toxic effect of the gene product on the h ...19883131142
molecular dynamics simulations of ribonuclease t1: analysis of the effect of solvent on the structure, fluctuations, and active site of the free enzyme.molecular dynamics simulations were performed on ribonuclease t1 (rnase t1; ec 3.1.27.3) to determine a structure for the free enzyme. simulations starting with the x-ray coordinates for the 2'gmp-rnase t1 complex were done in vacuo and with an 18-a water ball around the active site using stochastic boundary conditions to understand the influence of water on both the structure and fluctuations of the enzyme. removal of 2'gmp caused structural changes in the loop regions, including those directly ...19883139027
two-dimensional 1h-nmr investigation of ribonuclease t1. resonance assignments, secondary and low-resolution tertiary structures of ribonuclease t1.ribonuclease t1 was studied by two-dimensional 1h-nmr spectroscopy. resonance assignments were obtained for the backbone protons of 95 amino acid residues and most of its side-chain protons using sequence-specific assignment procedures. the secondary structure elements of ribonuclease t1 were identified by an investigation of medium- and long-range nuclear overhauser effects between the backbone and c beta protons. a low-resolution three-dimensional structure of ribonuclease t1 was deduced from ...19883143569
mycological identification of pulmonary aspergilloma caused by aspergillus oryzae with proliferating heads. 19883148401
amino-acid sequence of ribonuclease t2 from aspergillus oryzae.the amino acid sequence of ribonuclease t2 (rnase t2) from aspergillus oryzae has been determined. this has been achieved by analyzing peptides obtained by digestions with achromobacter lyticus protease i, staphylococcus aureus v8 protease, and alpha-chymotrypsin of two large cyanogen bromide peptides derived from the reduced and s-carboxymethylated or s-aminoethylated protein. digestion with a. lyticus protease i was successfully used to degrade the n-terminal half of the s-aminoethylated prote ...19883169020
activation of antioxidant activity in natural medicinal products by heating, brewing and lipophilization. a new drug delivery system.on the basis of the authors' previous hypothesis (1) that treatment of natural plant products with heating and gastric juice results in liberation of low molecular weight compounds with antioxidant activity that exist in the native products as repeating subunits of high molecular weight polymers, they have developed specially treated natural health or medicinal products in which several identifiable low molecular weight compounds with antioxidant activity are liberated and activated. the princip ...19883219997
[the role of alpha-amylase in baker's asthma].we report a case of asthma in a baker provoked by an additive which is generally used in bread making, namely alpha-amylase, an extract of aspergillus oryzae. skin tests to alpha-amylase were positive in a concentration of 0.1 micrograms/ml. specific ige was detected to this enzyme. a provocation test to alpha-amylase was positive with a fall of the fev1 of 42%. provocation tests to flour gave a negative immediate and delayed reaction. progress was made towards the disappearance of symptoms afte ...19883263674
[comparison of chemical and thermal stability of soluble and immobilized alpha-amylases from b. licheniformis and a. oryzae].alpha-amylases from b. licheniformis and a. oryzae, which differ in their thermal stability, were studied with respect to their resistance to chemical denaturants as guanidine hydrochloride, urea, aliphatic alcohols, and formaldehyde. moreover, the thermal and chemical stabilities of both enzymes were compared after their covalent binding to gamma-aminopropyl silica. the thermolabile alpha-amylase (a. oryzae) as well as the thermostable alpha-amylase (b. licheniformis) are remarkably stabilized ...19883266840
alpha-amylase structure and activity.two computerized methods of predicting protein secondary structure from amino acid sequences are evaluated by using them on the alpha-amylase of aspergillus oryzae, for which the three-dimensional structure has been determined. the methods are then used, with amino acid alignments, to predict the structures of other alpha-amylases. it is found that all alpha-amylases of known amino acid sequence have the same basic structure, a barrel of eight parallel stretches of extended chain surrounded by e ...19883267138
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 ...19883357058
[changes in the composition and unsaturated state of the neutral lipid fraction during the development of the fungus aspergillus oryzae]. 19883412198
purification and properties of an extracellular glucoamylase from a diastatic strain of saccharomyces cerevisiae.the extracellular glucoamylase from certain strains of saccharomyces cerevisiae can be purified from culture medium by a simple chromatographic procedure. the native enzyme is heavily glycosylated and has an mr of about 250,000, but gel filtration indicates the existence of oligomers of larger size. dissociation yields a form of mr about 70,000. the glucoamylase is rich in serine and threonine and in aspartic acid plus asparagine, and has a pi of 4.62 and a ph optimum of 4.5-6.5. the thermostabi ...19883124820
genetic transformation of an argb mutant of aspergillus oryzae.an argb mutant of aspergillus oryzae nrrl 492 has been genetically transformed with the aspergillus nidulans argb gene. protoplasts were generated with a combination of novozyme 234 and beta-glucuronidase and regenerated on sucrose-stabilized minimal medium without arginine as described for a. nidulans. a frequency of 5 to 10 transformants per mug of dna was obtained; however, most transformants appeared abortive. the a. nidulans argb gene and vector sequences appeared to be integrated into the ...198816347669
uptake of glycosylated ?-galactosidase into human brain synaptosomes: occurrence of two different systems for specific glycosides.uptake of glycoproteins into brain nerve terminals was studied, using glycosylated ?-galactosidase and human brain synaptosomes. a series of p-aminophenyl ?- or ?-glycosides were covalently bound to ?-galactosidase purified from aspergillus oryzae and uptake of the enzyme into human brain synaptosomes was measured. ?-galactosidase coupled with ?-d-mannoside (?-d-man ?-gal) was the best to be taken up among glycoconjugates tested. the uptake was dependent on the amount of ?-d-man ?-gal, the incub ...198820501274
purification of ribonuclease t1.an improved method for purifying ribonuclease t1 from aspergillus oryzae is described. the method uses gradient elution from deae-cellulose and sulfopropyl-sephadex columns followed by gel filtration on sephadex g-50 to give almost 100 mg (50% yield) of ribonuclease t1 from 100 g of starting material in less than 5 days.19873126677
two histidine residues are essential for ribonuclease t1 activity as is the case for ribonuclease a.ribonuclease t1 (rnase t1, ec 3.1.27.3) is a guanosine-specific ribonuclease that cleaves the 3',5'-phosphodiester linkage of single-stranded rna. it is assumed that the reaction is generated by concerted acid-base catalysis between residues glu-58 and his-92 or his-40. from the results of chemical modification and nmr studies, it appeared that the residue glu-58 was indispensable for nucleolytic activity. however, we have recently demonstrated that glu-58 is an important but not an essential re ...19873126807
study on immobilization of aminoacylase from aspergillus oryzae on macroporous copolymers.the aminoacylase from aspergillus oryzae was adsorbed on polymer carriers where the enzyme showed excellent catalyzing activity and operating stability. it was found that the pore structure and functional group were the basic factors which affected the activity of the adsorbed enzyme. the hydrophobility of the carriers did not play an important role in the enzymatic resolution. various factors, such as percentage and nature of cross-linking agent, porogenic agents and functionalizing agents whic ...19873452428
transformation of aspergillus oryzae using the a. niger pyrg gene.a transformation system for aspergillus oryzae based on the orotidine-5'-phosphate decarboxylase gene (pyrg) was developed. transformation frequencies of up to 16 transformants per microgram of dna were obtained with the vector pab4-1, which carries the pyrg gene of a. niger. southern blotting analysis showed that vector dna sequences were integrated into the chromosomal dna, in various copy numbers and presumably at different sites. efficient cotransformation of an unselectable gene was also sh ...19873481025
simple method for screening aflatoxin-producing molds by uv photography.uv absorption by aflatoxins was monitored in gy agar medium by uv photography. in the uv photographs, aflatoxin-producing molds were identified as gray or black colonies, whereas aflatoxin-nonproducing molds appeared as white colonies. by cellophane transplantation experiments and silica gel thin-layer chromatography, the products absorbing uv light substantially were found to be mainly aflatoxins b1 and g1 excreted from the mold mycelium into the agar medium. uv absorption did not occur when th ...19873105453
effective reduction of lactose maldigestion in preschool children by direct addition of beta-galactosidases to milk at mealtime.we examined the efficiency of two beta-galactosidase preparations--one derived from the yeast, kluyveromyces lactis (lactaid), the other derived from the fungus, aspergillus oryzae (takamine)--to assist the in vivo digestion of lactose consumed by healthy guatemalan preschool children. milk prehydrolyzed by in vitro incubation with enzymes was used as the standard of reference, and the degree of incomplete digestion of lactose from 240 ml of milk was determined using the hydrogen breath test. in ...19873106927
facile preparation and some applications of an affinity matrix with a cleavable connector arm containing a disulfide bond.a versatile affinity matrix in which the ligand of interest is linked to the matrix through a connector arm containing a disulfide bond is described. it can be synthesized from any amino-substituted matrix by successive reaction with 2-imino-thiolane, 5,5'-dithiobis(2-nitrobenzoic acid), and a thiol derivative of the ligand of choice. the repertoire of ligands can be significantly increased by the appropriate use of avidin-biotin bridges. after adsorption of the material to be fractionated, elut ...19873110760
does oral enzyme replacement therapy reverse intestinal lactose malabsorption?the effects of oral enzyme replacement therapy on breath hydrogen excretion and symptoms after milk ingestion were studied in lactase-deficient patients. sixteen symptomatic patients underwent interval hydrogen breath tests using whole milk as substrate. each study was repeated with the addition of 250 mg of beta-d-galactosidase derived from aspergillus oryzae (lactrase) given orally with the milk. subsequently seven of those 11 patients who did not normalize their hydrogen excretion with 250 mg ...19873111243
protein dynamics. a time-resolved fluorescence, energetic and molecular dynamics study of ribonuclease t1.studies using time-resolved fluorescence depolarization were performed on the internal motion of trp 59 of ribonuclease t1 (ec 3.1.27.3) in the free enzyme, 2'-gmp-enzyme complex and 3'-gmp-enzyme complex. the trp 59 motion was also studied in the free enzyme using molecular dynamics simulations. energetic analysis of activation barriers to the trp 59 motion was performed using both the transition state theory and kramers' theory. the activation parameters showed a dependence on solvent viscosit ...19873111558
frequency domain measurements of the fluorescence lifetime of ribonuclease t1.using multifrequency phase/modulation fluorometry, we have studied the fluorescence decay of the single tryptophan residue of ribonuclease t1 (rnase t1). at neutral ph (7.4) we find that the decay is a double exponential (tau 1 = 3.74 ns, tau 2 = 1.06 ns, f1 = 0.945), in agreement with results from pulsed fluorometry. at ph 5.5 the decay is well described by a single decay time (tau = 3.8 ns). alternatively, we have fitted the frequency domain data by a distribution of lifetimes. temperature dep ...19873115328
structures of oligosaccharides on beta-galactosidase from aspergillus oryzae.the carbohydrate portions of beta-galactosidase from aspergillus oryzae were found to be composed of two types of sugar chains. they were released equally well with endo-beta-n-acetylglucosaminidase h, but were distinct in their chain length. the long sugar chains (fraction i), corresponding to 4% of the total carbohydrate chains, were composed of galactomannan-type oligosaccharides, which consisted of mannose, galactose, glucose, and glucosamine in the molar ratios of 30.0, 16.4, 1.4, and 2.1 p ...19873117779
studies of protease and protease inhibitors in familial amyloidotic polyneuropathy.serum levels of 6 protease inhibitors, alpha 1-antitrypsin, cl inactivator, alpha 2-macroglobulin, antithrombin-3, alpha 1-antichymotrypsin and inter-alpha-trypsin inhibitor were measured in patients with familial amyloidotic polyneuropathy (fap) and a control group without neurologic disease. no significant differences were observed between the 2 groups. the proteolytic effect of brinase, an enzyme from aspergillus oryzae, on amyloid tissue sections from patients with fap was also evaluated. am ...19873316509
allergic bronchopulmonary aspergillosis due to aspergillus oryzae.a 19-year-old female student with allergic bronchopulmonary aspergillosis (abpa) due to aspergillus oryzae is reported. this organism was used for fermentation starter to make soybean paste in her father's workshop adjacent to the home where she lived. abpa might be considered an occupational disease in certain situations.19872433099
[enzymatic isolation of the pyramidal neurons of the rat hippocampus]. 19873034680
[development of new plate tests for the detection of microbial hydrolysis of esters and oxidation of 2-hydroxycarboxylic acids].the application of the thin-agar-layer coated filter culture technique (z. naturforsch. 42c, 1082 (1987)) has been extended to the detection of ester hydrolysis and 2-hydroxyacid oxidation by microbial colonies. the former was performed by spraying with bromocresol purple and the latter with a salicylhydrazide reagent. under the optimized conditions, the hydrolysis activity of more than 20 mumol/h.g-wet cells and the oxidation activity of more than 40 mumol/h.g-wet cells were usually detected di ...19872966500
nucleotide sequence of the alpha-amylase gene (alp1) in the yeast saccharomycopsis fibuligera.the complete nucleotide sequence of the secretable alpha-amylase gene alp1 from the yeast saccharomycopsis fibuligera has been determined. the alp1 dna hybridized to a polyadenylated rna of 2.0 kilobases. a single open reading frame encodes a 494-amino acid protein which is highly homologous with alpha-amylase (taka-amylase) of a fungus aspergillus oryzae.19873497057
differential scanning calorimetric study of the thermal unfolding of taka-amylase a from aspergillus oryzae.the thermally induced unfolding of taka-amylase a, isolated from aspergillus oryzae, was studied by differential scanning calorimetry. the experimental curves of excess apparent specific heat vs. temperature showed a single asymmetric peak. curve resolution indicated that this asymmetry is due to the two-state unfolding of three domains in the molecule, with dissociation of the single tightly bound ca2+ ion occurring during the unfolding of the last domain. further indication of the dissociation ...19873498514
studies on the active site of taka-amylase a: its action on phenyl maltooligosides with a charge at their non-reducing-ends.five modified moltooligosaccharides, phenyl o-6-amino-6-deoxy-alpha-d- glucopyranosyl- (1----4)-o-alpha-d-glucopyranosyl-(1----4)-o-alpha-d-glucopyranosyl-(1-- --4)- alpha-d-glucopyransoide (ag4p), phenyl o-(alpha-d-glucopyranosyluronic acid)-(1----4)-o-alpha-d-glucopyranosyl-(1----4)-o-alpha-d-glucopyran osy l- (1----4)-alpha-d-glucopyranoside (cg4p), phenyl o-6-amino-6-deoxy-alpha-d-glucopyranosyl-(1----4)-o-alpha-d-glucopyra nos yl- (1----4)-o-alpha-d-glucopyranosyl-(1----4)-o-alpha-d-glucopy ...19873501785
effect of yeast culture and aspergillus oryzae fermentation extract on ruminal characteristics and nutrient digestibility.four nonpregnant and nonlactating holstein cows fitted with ruminal fistulas were assigned to each of four diets in a 4 x 4 latin square design. dietary treatments were 1) basal diet containing 50% concentrate; 2) basal diet plus 90 g/d yeast culture; 3) basal diet plus 2.63 g/d aspergillus oryzae fermentation extract; 4) basal diet plus 90 g/d of a. oryzae fermentation extract and yeast culture. cows were fed diets at a rate of 86 g dm/kg bw.75 for 14 d adaptation followed by an 8-d collection ...19873680724
immobilization of single-strand specific nuclease (s1 nuclease) from aspergillus oryzae.s1 nuclease from aspergillus oryzae (ec 3.1.30.1) was coupled to gelatin-alginate composite matrix using the residual free aldehyde groups on the surface of glutaraldehyde crosslinked matrix. the immobilized enzyme retained approximately 10% activity of the soluble enzyme. when partially purified enzyme was bound to the matrix, the immobilized preparation did not show any detectable enzyme activity. however, the activity could be restored when the coupling was carried out in the presence of a co ...19872820305
role of aspergillus amylase in baker's asthma. 19862417074
improved purification of aspergillus oryzae 1,2-alpha-mannosidase by using mannan gel affinity chromatography.in order to facilitate the purification of 1,2-alpha-mannosidase from an enzyme product of aspergillus oryzae, we have devised a rapid and simple procedure. a partially purified enzyme preparation obtained from the a. oryzae enzyme product, by means of ammonium sulfate fractionation followed by cm-sephadex c-50 chromatography, was subjected to affinity chromatography with baker's yeast mannan gel as an adsorbent. 1,2-alpha-mannosidase was retarded and well separated from the major protein peak o ...19863700367
the disulphide folding pathway of ribonuclease t1.the pathway of unfolding and refolding that accompanies, respectively, the breakage and formation of the two disulphide bonds of ribonuclease t1 has been determined kinetically and compared with those of other proteins.19863735429
invasion of paranasal sinuses by aspergillus oryzae.a 24-year-old male patient receiving chemotherapy for acute promyelocytic leukemia developed fever, right periorbital swelling and mild right proptosis. a head scan showed opacification of the right maxillary and ethmoid sinuses with adjacent soft tissue swelling. biopsy of the nasal mucosa demonstrated the typical septate hyphae of aspergillus species which was later shown on culture to be aspergillus oryzae. a. oryzae has only rarely been reported in human disease and there is confusion as to ...19863796709
an immunochemical study of neurospora nucleases.nucleases derived from neurospora crassa mycelia with neutral single-strand (ss) endodeoxyribonuclease activity have been examined by immunochemical techniques and by sodium dodecyl sulfate - dna gel electrophoresis. all of the intracellular nucleases, which have different divalent metal ion requirements, different strand specificities with single- and double-strand dna, different modes of action on dna and rna, and other distinguishing characteristics, are immunochemically related to neurospora ...19863013242
5-iodoribose 1-phosphate, an analog of ribose 1-phosphate. enzymatic synthesis and kinetic studies with enzymes of purine, pyrimidine, and sugar phosphate metabolism.the 5'-deoxy-5'-iodo-substituted analogs of adenosine and inosine are cytotoxic to tumor cells that have high activities of 5'-methylthioadenosine phosphorylase and purine nucleoside phosphorylase, respectively (savarese, t.m., chu, s-h., chu, m.y., and parks, r. e., jr. (1984) biochem. pharmacol. 34, 361-367). 5-iodoribose 1-phosphate (5-irib-1-p), the common intracellular metabolite of these 5'-iodonucleosides, has been synthesized enzymatically from 5'-deoxy-5'-iodoadenosine via adenosine dea ...19862934389
production of aflatoxins by strains of the aspergillus flavus group maintained in atcc.a total of 169 strains of the aspergillus reference cultures in the aspergillus flavus group maintained in the american type culture collection (atcc) were studied for their aflatoxin-producing abilities in rice, peanut and semisynthetic medium, utilizing high pressure liquid chromatography. fifty-nine of the strains examined were positive for aflatoxin formation. no strains of the food fungi a. oryzae or a. sojae produced detectable levels of aflatoxins, while 33-85% of the strains of a. flavus ...19863083260
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