Showing papers in "Bioscience, Biotechnology, and Biochemistry in 1993"
TL;DR: The level of momilactone A produced appeared to be enough to prevent the growth of pathogenic fungi such as Pyricularia oryzae, thus indicating the importance of this phenomenon in the defense systems of rice plants.
Abstract: Induction of phytoalexin formation in suspension-cultured rice cells by a series of N-acetylchitooligosaccharides and chitooligosaccharides was studied N-acetylchitooligosaccharides larger than hexaose induced the formation of momilactones A and B as well as oryzalexins A, B, and D at very low concentrations like 10− 9–10− 6 M (N-acetylchitoheptaose) GlcNAc oligomers smaller than trimers had almost no activity and a series of deacetylated chitooligosaccharides were also inactive Strict requirement for the size and structure of GlcNAc oligomers as well as the sensitivity to them strongly indicates the presence of recognition systems specific for these compounds in rice cells The level of momilactone A produced reached 100–500 μg/g of cultured cells, which appeared to be enough to prevent the growth of pathogenic fungi such as Pyricularia oryzae, thus indicating the importance of this phenomenon in the defense systems of rice plants Suspension-cultured cells obtained only from a suitable period of cult
265 citations
TL;DR: It is suggested that chitosan combined bile acids in the digestive tract, and that the combined product was excreted into the feces, so that the cholesterol poool in the body was decreased and the level of serum chrolesterol consequently decreased.
Abstract: The present study is the first to report the hypocholesterolemic effect of chitosan on humans. When 3–6 g/day of chitosan was given in the diet to 8 healthy males, total serum cholesterol significantly decreased, and when the ingestion was stopped, the value increased to the level before ingestion. Serum HDL-cholesterol was increased significantly by the ingestion of chitosan. The excreted amounts of primary bile acids, cholic acid and chenodeoxycholic acid, into the feces was significantly increased by the ingestion of chitosan, and the amount of cholic acid excretion decreased significantly after the ingestion was stopped. These facts suggest that chitosan combined bile acids in the digestive tract, and that the combined product was excreted into the feces. This, in turn, deceased the resorption of bile acids, so that the cholesterol poool in the body was decreased and the level of serum chrolesterol consequently decreased.
234 citations
TL;DR: Fraction of hydrolyzates prepared from sardine muscle by Bacillus licheniformis alkaline protease was apparently rich in acidic amino acids, poor in hydrophobic ones, and effective for use as a physiologically functional food material by virtue of little bitterness, a fish odor and powerful ACE inhibitory activity.
Abstract: Hydrolyzates which inhibit the angiotensin I-converting enzyme (ACE) were prepared from sardine muscle by Bacillus licheniformis alkaline protease. Considering the practical application of preparations as a functional food material, the best proteolytic conditions with respect to taste, solubility and ACE inhibitory activity were a 0.3 wt% addition of the enzyme and 17-h proteolysis at 50°C and pH 9.0. The preparations under these conditions had potent activity (IC50=0.26 mg protein/ml). Fractionation of the preparations on an ODS column with ethanol resulted in the production of more potent inhibitors. The most potent activity was obtained when eluting with 10% ethanol (IC50=0.015 mg protein/ml). This fraction was apparently rich in acidic amino acids, poor in hydrophobic ones, and effective for use as a physiologically functional food material by virtue of little bitterness, a fish odor and powerful ACE inhibitory activity.
193 citations
TL;DR: It is assumed that orally administered catechins will inhibit intestinal α-amylase or sucrase, thereby deterring the digestion of certain amounts of starch or sucrose and eventually reducing the plasma glucose levels.
Abstract: The influence of tea catechins on the absorption of starch or sucrose was investigated in vivo. Tea catechins were administered orally to rats before soluble starch or sucrose administration. Saccharide-dosed rats were killed and the blood and the contents of the intestine were collected at intervals over two hours. Catechins of certain concentrations suppressed the increase of plasma glucose levels, thus concurrently suppressing insulin activity. Increased activity of intestinal α-amylase by starch dosing was inhibited markedly in the catechin-administered rats. Sucrase on the brush border membrane was also inhibited by prior catechin administration. From these results it was assumed that orally administered catechins will inhibit intestinal α-amylase or sucrase, thereby deterring the digestion of certain amounts of starch or sucrose and eventually reducing the plasma glucose levels.
181 citations
TL;DR: The soybean allergenic protein, Gly m Bd 30K, which is most strongly and frequently recognized by the IgE antibodies in sera of soybean-sensitive patients with atopic dermatitis, has been characterized and shown to have about 30% sequence homology with Der pI, a house dust mite allergen that is a thiol proteinase from Dermatophagoides pteronyssius.
Abstract: The soybean allergenic protein, Gly m Bd 30K [Ogawa et al., J. Nutr. Sci. Vitaminol., 37, 555-565 (1991)] which is most strongly and frequently recognized by the IgE antibodies in sera of soybean-sensitive patients with atopic dermatitis, has been characterized. The allergen was isolated from the crude 7S-globulin fraction as an oligomeric form with a molecular weight of more than 3000,000 by gel-filtration chromatography. On two-dimensional gel electrophoresis, the native oligomeric allergen had an isoelectric point of about pH 4.5 and was dissociated into a monomeric form with a molecular weight of about 32,000 by the treatment with sodium dodecyl sulfate and 2-mercaptoethanol. The monomeric allergen had an N-terminal amino acid sequence and amino acid composition identical with those of the soybean seed 34-kDa oil-body-associated protein or the soybean vacuolar protein P34 with close homology to papain-like thiol proteinases [Kalinski et al., J. Biol. Chem., 267, 12068 (1992)]. The identity was further confirmed by the immunological cross-reactivity to the antibodies produced against each of the purified allargen and the 34-kDa oil-body-associated protein. By this observation, Gly m Bd 30K was shown to have about 30% sequence homology with Der pI, a house dust mite allergen that is a thiol proteinase from Dermatophagoides pteronyssius.
177 citations
TL;DR: The inhibitory activity of an angiotensin I-converting enzyme detected in soy sauce was fractionated into two major fractions by gel filtration chromatography on Bio-gel P-2 after treating with ethanol, and the purified ACE inhibitor was identified as nicotianamine.
Abstract: The inhibitory activity of an angiotensin I-converting enzyme (ACE) detected in soy sauce was fractionated into two major fractions of high molecular weight (Hw) and low molecular weight (Lw) by gel filtration chromatography on Bio-gel P-2 after treating with ethanol. The Hw fraction reduced the blood pressure in hypertensive rats after orally administering, while the Lw fraction did not. The ACE inhibitor in the Hw fraction was further purified by Dowex 50W ion-exchange chromatography and four subsequent steps of HPLC. On the basis of the SIMS-mass spectrum, NMR spectrum and other characteristics, the purified ACE inhibitor was identified as nicotianamine (N-[N-(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]azetidine-2- carboxylic acid). The IC50 value for this ACE was 0.26 microM.
174 citations
TL;DR: Production of Poly(γ-glutamic acid) by Bacillus subtilis F-2-01 by Hidetoshi Kubota, Toshio Matsunobu, Kazumichi Uotani, Hidehi Takebe, Atsuyuki Satoh, ToshIO Tanaka & Makoto Taniguchi
Abstract: (1993). Production of Poly(γ-glutamic acid) by Bacillus subtilis F-2-01. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 7, pp. 1212-1213.
155 citations
TL;DR: From the results of amino acid sequence, amino acid composition analyses and immunological analyses, it was suggested that these six enzyme proteins were derived as isozyme(s) from at least four different genes.
Abstract: Stable and potent fibrinolytic enzymes (six homogeneous proteins) were purified to homogeneity from extracts of the lyophilized powder of an earthworm, Lumbricus rubellus. The molecular weight of each enzyme estimated by SDS-polyacrylamide gel electrophoresis was different from those by gel filtration chromatography in the six purified proteins. The exact molecular weight of each enzyme (F-III-2, F-III-1, F-II, F-I-2, F-I-1, and F-I-0) measured by ion-spray MS analysis was 29,662, 29,667, 24,664, 24,220, 24,196, and 23,013, respectively. The isoelectric point (pI) of each enzyme was 3.40, 3.60, 4.20, 4.00, 4.30, and 4.85, respectively. The enzymes were single polypeptide chains. They had a very strong fibrinolytic activity and the maximum reactivity for chromogenic substrates from pH 9-11. The enzymes, acidic proteins that had abundant asparagine and aspartic acid, and low lysine in their amino acid composition, did not contain component sugars. The enzymes were stable at from pH 1-11 and up to 60 degrees C. Studies on substrate specificity and inhibition indicated that these enzymes were alkaline trypsin-like serine proteases. N-Terminal amino acid sequences of the enzymes had local similarities to those of trypsin-like enzymes such as elastase and coagulation factor IX. From the results of amino acid sequence, amino acid composition analyses and immunological analyses, it was suggested that these six enzyme proteins were derived as isozyme(s) from at least four different genes.
153 citations
TL;DR: Two bacterial strains, CA06 and CA10, that assimilate carbazole (CAR) as the sole source of carbon and nitrogen were isolated from 202 farm soil samples and 4 activated sludge samples and identified as Pseudomonas spp.
Abstract: Two bacterial strains, CA06 and CA10, that assimilate carbazole (CAR) as the sole source of carbon and nitrogen were isolated from 202 farm soil samples and 4 activated sludge samples, and identified as Pseudomonas spp. Growth conditions for strains CA06 and CA10 on CAR were examined. Anthranilic acid (AN) and catechol (CAT) were identified as the main metabolites of CAR by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). When strains CA06 and CA10 were cultivated in a medium containing 17mM CAR, 1.4mM AN, and 0.1 mM CAT were accumulated in the culture broth, but AN disappeared after 140 h of incubation. An initial oxidation product, 2ʹ -aminobiphenyl-2,3-diol, and a meta-cleavage product, 2-hydroxy-6-oxo-6-(2ʹ -aminophenyl)hexa-2,4-dienoic acid, were tentatively identified in the culture broth of CAR by GC-MS. When AN was used for a substrate in culture by these strains, CAT and a small amount of cis, cis-muconate was detected by HPLC. This conversion sugges...
153 citations
TL;DR: In this paper, the relative oxidative stability of six kinds of typical polyunsaturated fatty acids (PUFAs) was investigated in an aqueous solution (pH=7.4 at 37°C) with Fe2+ascorbic acid as a catalyst.
Abstract: The relative oxidative stability of six kinds of typical polyunsaturated fatty acids (PUFAs) was investigated in an aqueous solution (pH=7.4 at 37°C) with Fe2+-ascorbic acid as a catalyst. The highest stability was shown by docosahexaenoic acid (22: 6n-3, DHA), followed by eicosapentaenoic (20: 5n-3), arachidonic (20: 4n-6), α-linolenic (18: 3n-3), γ-linolenic (18: 3n-6), and linoleic (18: 2n-6, LA) acids, indicating that the stability increased with increasing degree of unsaturation. The significant difference found between α-linolenic and γ-linolenic acids also suggests the higher oxidative stability of n-3 PUFAs than of n-6 PUFAs in an aqueous solution. Moreover, when a mixture of DHA and LA was oxidized in an aqueous solution, the stability increased with increasing molar ratio of DHA to LA in the mixture. This characteristic oxidative stability of PUFAs in the aqueous phase is quite different from that in the neat phase, and can be explained by correlating with the conformation of PUFAs in the aqueou...
144 citations
TL;DR: In this article, the composition and structures of group B saponin in soybean seeds were investigated and the structures were characterized as 2,3-dihydro-2,5-dimethyl-6-methyl-4H-pyran-4-one (DDMP) attaching through an acetal linkage to the C-22 hydroxyl of the aglycones of soyasaponins V, I, II, III, and IV, respectively, by UV, IR, MS, and NMR.
Abstract: The composition and the structures of native “group B saponin” in soybean seeds were reinvestigated. Five kinds of saponins named soyasaponins αg, βg, βa, γg, and γa, according to elution order from HPLC, were isolated and the structures were characterized as 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) attaching through an acetal linkage to the C-22 hydroxyl of the aglycones of soyasaponins V, I, II, III, and IV, respectively, by UV, IR, MS, and NMR. DDMP-conjugated saponins were detected as major saponin constituents by extraction under mild conditions, and soyasaponins I–V were not detected. Therefore it was strongly suggested that these DDMP-conjugated saponins were genuine saponins in the intact soybeans.
TL;DR: 9) The structural formulae of catechins and theafiavins are shown and a crude enzyrne solution was prepared by a slight medification of the precedure of Dahlqvist, i.
Abstract: (1993). Inhibition of Rat Small Intestinal Sucrase and α-Glucosidase Activities by Tea Polyphenols. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 1, pp. 123-124.
TL;DR: A discrepancy in heat and acidic pH stability found between the two antibodies as discussed with regard to their protein structures is found.
Abstract: Productivity and some properties of anti-Human Rotavirus (HRV) hen egg yolk antibody (IgY) were compared with those of anti-HRV rabbit serum antibody (IgG). The hens immunized with HRV (Wa strain, serotype 1 and Mo strain, serotype 3) were found to continuously to lay eggs without any change in the egg laying rate and the yolk of the eggs laid over a year showed a high level of neutralization titer against HRV. The production of anti-HRV IgY by a hen (one year) was at least 15 times (anti-Wa) and 120 times (anti-Mo) more effective than those by an immunized rabbit in the neutralization titer of the antibodies. The stability of anti-HRV IgY at temperature above 70 degrees C and low pH 2-3 was less than that of anti-HRV rabbit IgG. The temperature corresponding to the maximum of denaturation endotherm (Tmax) of IgY was 73.9 degrees C while that of rabbit IgG was 77.0 degrees C in the analysis by differential scanning calorimetry. This discrepancy in heat and acidic pH stability found between the two antibodies as discussed with regard to their protein structures.
TL;DR: In this article, deegummed silk was dissolved in a mixture of CaCl2 and ethanol at low temperature, and then it was kept in an air-conditioned room for gelation.
Abstract: Degummed silk was dissolved in a mixture of CaCl2 and ethanol at low temperature The concentration and pH of the centrifuged, filtered, and dialyzed silk solution were adjusted, and then it was kept in an air-conditioned room for gelation The mechanism of the gelation and the gel structure were studied It was found that the gel was formed due to the formation of beta-structure in the fibroin solution The gelation was dependent on the pH of the fibroin solution
TL;DR: In this paper, the effects of pH and temperature on reaction kinetics of degradation of tea catechins were investigated, and the stability of catechin in green tea infusion was subject to the turning point temperature.
Abstract: Stability of tea catechins during heat processing was examined. Effects of pH and temperature on reaction kinetics of degradation of tea catechins were investigated. Reaction of – EC was accelerated at pH higher than 6.0, inhibited at those lower than 5.0. A dominant reaction of – EC in slightly acidic media was isomerization. The apparent first order reaction proceeded in slightly acidic media under sterilization conditions. A similar reaction proceeded for – EC, – EGC, – ECg, and – EGCg in green tea infusion at temperatures below 95°C. A turning point temperature on an Arrhenius plot was observed at 82°C. A great difference of apparent activation energies was observed lower and higher than 82°C. The reaction rate constant of catechins in slightly acidified tea infusion was less than half as much as the constant in the original infusion. The stability of catechins in green tea infusion was subject to the turning point temperature.
TL;DR: It was found that a previous supply of the IgY (1 h before HRV infection) completely prevented the HRV-induced diarrhea in suckling mice and the preventive effect was decreased as the time gap between IgY administration andHRV infection was longer.
Abstract: The neutralization titer of anti-human rotavirus (HRV) IgY was completely inactivated by pepsin at pH 2.0. However, it was not significantly affected by trypsin or chymotrypsin under certain conditions. The immunological activity of the IgY was observed in the intestine of suckling mice for 2 h after oral administration and the activity rapidly decreased thereafter. The effects of oral supply of IgY were thus estimated for HRV-induced diarrhea in suckling mice and it was found that a previous supply of the IgY (1 h before HRV infection) completely prevented the HRV-induced diarrhea. The preventive effect was decreased as the time gap between IgY administration and HRV infection was longer. However, the oral supply of the IgY within 24 h after HRV infection was still effective and decreased the incidence of HRV diarrhea in suckling mice.
TL;DR: The results suggest that the two individual fractions obtained from marine algae possessed the ability to activate macrophages in vitro and in vivo in different ways.
Abstract: Two discrete immunomodulating fractions were obtained from marine algae (Porphyra yezoensis): one was the Porphyra water-soluble fraction (PWSF) which was extracted with hot water from the whole body of algae, and the other was the Porphyra acid-soluble fraction (PASF) which was extracted with acid from the residue. The major constituent in both PWSF and PASF was a polysaccharide, the total sugar concentration in PWSF (56.4%) being lower than that in PASF (82.2%). The high contents of 3,6-anhydrogalactose and sulfate indicated the porphyran structure in PWSF and PASF. The results of an in vitro culture assay with proteose peptone-induced macrophages from mice revealed that PWSF and PASF both enhanced glucose consumption, as well as the production of nitrite and tumor necrosis factor (TNF), but that these were increased more by PWSF than by PASF. PWSF augmented IL-1 secretion from these macrophages, while PASF did not. On the other hand, the carbon clearance activity of phagocytes from mice injected intrap...
TL;DR: In this paper, Antitumoral and Antimicrobial activities of Bitter Sesquiterpene Lactones of Vernonia amygdalina, a Possible Medicinal Plant Used by Wild Chimpanzees.
Abstract: (1993). Antitumoral and Antimicrobial Activities of Bitter Sesquiterpene Lactones of Vernonia amygdalina, a Possible Medicinal Plant Used by Wild Chimpanzees. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 5, pp. 833-834.
TL;DR: Sucrose phosphorylase from Leuconostoc mesenteroides was found to catalyze transglycosylation from sucrose to catechins, which were efficient glycosyl acceptors and their transfer ratios were more than 40%.
Abstract: Sucrose phosphorylase from Leuconostoc mesenteroides was found to catalyze transglycosylation from sucrose to catechins. All catechins were efficient glycosyl acceptors and their transfer ratios were more than 40%. The acceptor specificity of the enzyme decreased in the following order: (−)-epicatechin gallate= (+)-catechin> (−)-epicatechin > (−)-epigallocatechin gallate> (−)-epigallocatechin. About 150 mg of the purified transfer product was obtained from 100 mg of (+)-catechin. Its structure was identified as (+)-catechin 3′-O-α-D-glucopyranoside (C-G) on the bases of the secondary ion mass spectrometry analysis, the component analyses of its enzymatic hydrolyzates, and the nulcear magnetic resonance analysis. The browning resistance of C-G to light irradiation was greatly increased compared to that of (+)-catechin. The solubility of C-G in water was 50-fold higher than that of (+)-catechin. The antioxidative activity of C-G in the aqueous system with riboflavin was almost equal to that of (+)-catechin....
TL;DR: A systematic method of extraction, fractionation, and purification of polysaccharides from Songshan Lingzhi (Ganoderma tsugae) with antitumor activity was established, finding protein-containing (1-->3)-beta-D-glucans showing the strongest activity.
Abstract: A systematic method of extraction, fractionation, and purification of polysaccharides from Songshan Lingzhi (Ganoderma tsugae) with antitumor activity was established.Seven glycans with strong antitumor activities were obtained from 14 water-soluble, and 15 water-insoluble fractions: FIo-a, FA-1, FII-1, FIII-2, and FIII-2-a, -b, and -c. FIo-a and FA-1 were proteincontaining glucogalactans associated with mannose and fucose. FII-l was a (1→3)-β-D-glucan having a lower protein content. The water-insoluble fractions FIII-2-a, -b, and -c were extracted with alkali, and were found to be protein-containing (1→3)-β-D-glucans showing the strongest activity. Chemical properties .and structure of each antitumor polysaccharide were compared with three fungi of the Ganoderma family, Kofukitake (G. applanatum), Mannentake (G. lucidum), and Songshan Lingzhi (G. tsugae).
TL;DR: Light micrographs of kuro-awabi showed that foot and the dorsal surface of foot were dominated by connective tissues, while adductor muscle was mainly composed of myofibrils, confirming light microscopic observations.
Abstract: Toughness and collagen content were measured for various muscle parts of the Japanese abalone, kuro-awabi (Haliotis discus), in relation to muscle structures. The dorsal surface of the foot was toughest, followed by the hard and soft part of the foot, then the upper and middle part of the adductor muscle, irrespective of being reared or wild specimens. When compared with other abalone species, kuro-awabi showed the highest toughness for all the muscle parts, followed by madaka (H. sieboldii) and megai-awabi (H. gigas), while ezo-awabi (H. discus hannai) was softest. Collagen content was parallel with muscle toughness: the higher the collagen content, the tougher the muscle. Light micrographs of kuro-awabi showed that foot and the dorsal surface of foot were dominated by connective tissues, while adductor muscle was mainly composed of myofibrils. Transmission electron micrographs demonstrated that myofibrils in the foot were surrounded by thick layers of collagen fibrils of about 1 μm, confirming light mic...
TL;DR: Inhibition by κ-Casein Glycomacropeptide and Lactoferrin of Influenza Virus Hemagglutination is described.
Abstract: (1993). Inhibition by κ-Casein Glycomacropeptide and Lactoferrin of Influenza Virus Hemagglutination. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 7, pp. 1214-1215.
TL;DR: Many strains of a black yeast, identified as Aureobasidium sp.
Abstract: Many strains of a black yeast, identified as Aureobasidium sp., were isolated by a selective medium, which contained mannitol as a main carbon source, and found to produce an extracellular biopolyester from glucose. The biopolyester was recovered as its calcium salt (61 g) from culture filtrate (1 liter). The acid hydrolysis and the transmethylation of the polyester proved L-malic acid to be its monomeric repeating unit. The saponification of the polyester, however, gave fumaric and maleic acids in about 20% yield, in addition to the malic acid. 1H NMR analysis proved the main-chain ester linkage of the polyester to be β-type. The apparent molecular mass was estimated to be distributed between about 6 and 11 kDa in a buffer (pH 6.8) with a high ionic strength (0.2 M).
TL;DR: The nucleotides of the xynA gene of Clostridium stercorarium were sequenced and it was shown that the repeated sequences were responsible for binding the enzyme to Avicel and were not essential for catalytic activity.
Abstract: The nucleotides of the xynA gene of Clostridium stercorarium were sequenced. The structural gene consists of an open reading frame of 1533 bp encoding 511 amino acids with an Mr of 56,519. The signal peptide cleavage site was identified by comparison with the N-terminal amino acid sequence of the enzyme produced by a recombinant Escherichia coli. Xylanase A consists of a catalytic domain belonging to family G at the N-terminus and two direct repeats of about 90 amino acids with a short spacing at the C-terminus. Deletion analysis showed that the repeated sequences were responsible for binding the enzyme to Avicel and were not essential for catalytic activity. The catalytic domain of this enzyme is highly homologous to xylanase A of Clostridium acetobutylicum (identity: 69%) and xylanase B of Bacillus pumilus (identity: 64%).
TL;DR: In this article, six angiotensin I-converting enzyme inhibitory peptides were isolated from a bonito bowels autolysate and their amino acid sequences were sequenced as Tyr-Arg-Pro-Tyr, Gly-His-Phe, Val-ArgPro, Ile-Lys-Pro, Leu-Arg Pro, and IleArg Pro.
Abstract: Six angiotensin I-converting enzyme inhibitory peptides were isolated from a bonito bowels autolysate. Their amino acids were sequenced as Tyr-Arg-Pro-Tyr, Gly-His-Phe, Val-Arg-Pro, Ile-Lys-Pro, Leu-Arg-Pro, and Ile-Arg-Pro. Peptides having corresponding amino acid sequences were synthesized by a solid-phase method and their inhibition of the activity measured. IC50 of these peptides were estimated to be 320, 1100, 2.2, 2.5, 1.0, and 1.8 μM, respectively. The role of carboxyl terminal proline residues on the inhibition is discussed.
TL;DR: Protein-containing polysaccharides extracted from fruiting bodies of a Chinese fungus, were fractionated and purified, and their antitumor activities were tested, out of which the following active fractions were obtained.
Abstract: Protein-containing polysaccharides extracted from fruiting bodies of a Chinese fungus named Feng Wei Gu, were fractionated and purified, and their antitumor activities were tested, out of which the following active fractions were obtained.FIo-a: A protein-containing xyloglucan, MW 280,000, polysaccharide: protein=76: 24 (w/w), polysaccharide consisting of Man: Gal: Xyl: Glc = 2: 12: 42: 42 (molar ratio). + 25.3°.FA-2: A protein-containing mannogalactan, MW 120,000, polysaccharide: protein = 76 : 16 (w/w), consisting of Xyl : Man: Gal = 9 : 35 : 56 (molar ratio), + 98.5°.FII-1: A Protein-containing xylan (62: 21 w/w). MW 200,000, +8.7°.FIII-1a: A protein-containing glucoxylan (15: 71 w/w), +30.7°, MW 90,000, consisting of Glc : Xyl = 40 : 44 (molar ratio).FIII-2a: A protein-containing xyloglucan, MW 70,000, polysaccharide: protein = 69: 3 (w /w), polysaccharide consisting of Xyl: Glc = 36 : 62 (molar ratio). + 38.6°.
TL;DR: The enzyme was solubilized from the microsomal fraction of Saccharomyces cerevisiae Kyokai No. 7, purified by a series of chromatographic separations and markedly inhibited by heavy metal ions such as Cd2+, Cu2+, Zn2+ and Hg2+, and sulfhydryl reagents.
Abstract: Alcohol acetyltransferase (AATase) catalyzes the esterification of isoamyl alcohol by acetyl coenzyme A. The enzyme was solubilized from the microsomal fraction of Saccharomyces cerevisiae Kyokai No. 7, using Triton X-100 and then purified by a series of chromatographic separations: Poly Buffer Exchanger 94 (PBE94), DEAE Toyopearl, Toyopearl HW60, hydroxyapatite, Octyl-Sepharose CL-4B, and hexanol affinity column chromatography. When the solubilized enzyme was put on PBE94, two active fractions were obtained. The enzyme obtained after affinity column chromatography had a single band on an SDS polyacrylamide gel, and its molecular mass was estimated to be 60 kDa. The enzyme was most active at pH 8.0 and 25°C. It was stable between pH 7.5 and 8.5, but was unstable at tempratures above l0°C. The activity was markedly inhibited by heavy metal ions such as Cd2+, Cu2+, Zn2+, and Hg2+, and sulfltydryl reagents. The Km for acetyl-CoA was 0.19 mM. The internal peptide sequences were also identified.
TL;DR: In this paper, Acetoxychavicol acetate as a Potent Inhibitor of Tumor Promoter-induced Epstein-Barr Virus Activation from Languas gaianga, a Traditional Thai Condiment.
Abstract: (1993). 1′-Acetoxychavicol Acetate as a Potent Inhibitor of Tumor Promoter-induced Epstein-Barr Virus Activation from Languas gaianga, a Traditional Thai Condiment. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 8, pp. 1344-1345.
TL;DR: It is considered that the first step to tofu-curd is the formation of a network by the protein particles at low calcium concentration, and the next step seemed to be the binding of the soluble proteins to the network by further addition of calcium and decreasing pH.
Abstract: Tofu-curd is made by the flocculation of proteins in soybean milk with an addition of calcium. The proteins consist of soluble and particle fractions. The influences of calcium and pH on the protein solubility of these fractions were investigated. The protein particles precipitated at lower calcium concentrations than that of the soluble proteins. This precipitation of proteins took place at higher pH with calcium than that without calcium. Therefore, it is considered that the first step to tofu-curd is the formation of a network by the protein particles at low calcium concentration. The next step was seemed to be the binding of the soluble proteins to the network by further addition of calcium and decreasing pH.
TL;DR: The cloned gene was found to be functional, since transformants of A. oryzae containing multiple copies of the pepA gene showed a 2-6 fold increase in acid protease activity compared with the recipient strain.
Abstract: 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 nucleotides. The deduced amino acid sequence of the A. oryzae PEPA has a high degree of homology (67%) to the A. awamori PEPA. Comparison with the amino acid sequence of A. awamori PEPA suggests that the A. oryzae PEPA may consist of a 78 amino acid prepro-peptide and 326 amino acid mature protein. The amino acid composition of the mature protein was almost consistent with that of the acid protease purified from A. oryzae reported previosuly. Southern hybridization analyses showed that the pepA gene exists as a singl...