An electrophoretically pure preparation of aminopeptidase was isolated from the cells of a strain of Bacillus subtilis which secreted saccharifying α-amylase. The purified pep-tidase was active only in the presence of manganese and cobaltous ions. Both the metal-lic ions were effective to a similar degree for the enzyme on most of the peptides used as the substrate. However, for hydrolysis of leucine amide by the enzyme was effective only cobaltous ion and, in this case, manganese ion showed to act as u competitive in-hibitor. On the other hand, for hydrolysis of certain other peptides such as glycyl pro-line, quite the opposite relationship was observed between those metallic ions. In the present paper is also described a new micro-assay method of amidase activity shown by the peptidase.

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Albino female rats were fed for 4 to 6 months on either a vitamin E-supplemented or on a vitamin E-unsupplemented diet.
Of the urea cycle enzyme activities, carbamyl phosphate synthetase and ornithine transcarbamylase were significantly higher in the vitamin E-supplemented group than in the vitamin E-unsupplemented one. Reversely, the activity of ornithine-keto acid trans-aminase was lower in the former group.
Urea level in the serum and liver was lower in the vitamin E-supplemented group, but urea excretion was accelerated in this group.
Activity of isocitric dehydrogenase was significantly higher in the vitamin E-supple-mented group. From these results, it is suggested that vitamin E is efficient for the de-toxication of ammonia in the animal body.

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Brevibacterium ammoniagenes ATCC 6872 was previously reported to accumulate a large amount of UMP from uracil or orotic acid.
Subsequent experiments were perfomed for ribotidation of pyrimidine analogues which were worthy of note as carcinostatic agents, and showed that Br. ammoniagenes ATCC 6872 was able to produce remarkably 6-aza-UMP, 5-fluoro-UMP, 5-hydroxy-UMP, 2-thio-UMP, 4-thio-UMP, UDP and -UTP from the corresponding pyrimidine analogues. The ribotides were isolated by chromatography on Dowex-1 and identified by paper chromatography, UV spectra, analyses of ribose and phosphate, and periodate consumption.
It was also found that 6-aza-UMP accumulated in the medium was converted to 6-aza-uridine by various microorganisms.

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A functional role of Co²⁺ and Mn²⁺ in the D-glucose- and D-xylose-isomerizing reactions by D-glucose-isomerizing enzyme obtained from the cells of Bacillus coagulans, strain HN-68 was investigated. (1) The enzyme required Co²⁺ and Mn²⁺ for D-glucose- and D-xylose-isomerizing activities, respectively. (2) The enzyme which bound the metal, C0²⁺ or Mn²⁺ -enzyme, was active form. Co²⁺ was bound to the enzyme in a molar ratio of 4:1. (3) The rate of activation by metal ion varied with incubation pH. (4) The binding of substrate to the enzyme was completely independent in the presence of metal ions. (5) However, it seemed unlikely that the Co²⁺ and Mn²⁺ acted as catalyzer on the reaction. (6) The binding sites for Co²⁺ and Mn²⁺ were different from each other. (7) The experi-mental data obtained might be successfully explained in terms of the suitable conforma-tional changes for D-glucose and D-xylose isomerization, which were induced in the catalytic sites of the enzyme by binding Co²⁺ and Mn²⁺, respectively.

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On the basis of the fasting plasma essential amino acid proportions, it has been pos-sible to develop very rapidly two diets, No. 152 and No. 153, comparable in protein efficiency to Diet No. 116.
The plasma profile concept was also found to be of use in interpreting published nutritional studies where the composition and quantity of diet consumed was reported.

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The distribution of the substituent in sodium carboxymethylcellulose (CMC) was studied in relation to its stabilization activity on milk proteins. The distribution of the substituent per glucose residue did not vary remarkably among 6 samples of CMC. However, the distribution along cellulose macromolecules varied and was more heterogeneous in 4 samples which could stabilize 1% α_s-casein at pH 5.0 and 5°C, than in other 2 samples which could not completely stabilize the protein.

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Two selection methods of non-foaming mutants of sake yeasts (a kind of cell wall mutants lacking the ability to form froth head in sake mash) are described. The mutants, being different in both the affinity to gas bubble and in the agglutinability from the parent, were concentrated, by removing the wild type cells with froth in froth flotation method and by removing them by agglutination caused by lactobacillus cells in cell agglutination method. Spontaneous non-foaming mutants of Kyokai No. 7 strain were isolated from the concentrates after 9 successive trials of each selection procedure at the rates of 50% by the former and 81% by the latter. The UV-induced mutants were also isolated from the concentrates after the 7 successions at the rates of 80% and 100%, respectively, by the former and by the latter. There were two types among the non-foaming mutants with respect to the agglutinability; the one was non- or almost non-agglutinable type (type 1) and the other was weakly-agglutinable one (type 2). The spontaneous mutants isolated by the froth flotation method were all of type 2, while 54% of those isolated by the cell agglutination method was of type I and the rest was type 2. On the other hand, only type I was found with the UV-induced mutants. It is inferred from the concentration rate determined by the froth flotation method in a model experiment that the mutation would occur spontaneously at a rate of 10^-8 and be stimulated about 100 fold by the UV-irradiation in Kyokai No. 7 strain. The usefulness of the non-foaming mutants are discussed from a practical point of view for sake production.

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In an attempt to study on metabolic changes in rats fed on an amino acid diet devoid of one branched chain amino acid and of niacin, rats were force-fed a leucine-free, isoleucine-free, valine-free or complete amino acid diet for 3 or 4 days and killed 3 hr after the feeding on day 4 or 5 to observe the body weight changes, the urinary nitrogen and N¹-methylnicotinamide (MNA), and liver tryptophanpyrrolase (TPase) and tyrosine-α-keto-glutarate transaminase (TKase) activities.
The excretion of the urinary nitrogen and MNA, TPase and TKase activities, and fat content of livers of rats force-fed these amino acid deficient diets were higher than those fed the complete amino acid diet. It was further confirmed in the present study that changes in TPase activity of rats given diets devoid of one essential amino acid were in the same direction with changes in urinary MNA which was observed in the previous studies on rats given threonine-free, tryptophan-free, methionine-free, lysine-free and complete amino acid diets. However, such metabolic changes in rats fed the leucine-free diet were not so remarkable, compared with those of rats fed the other amino acid deficient diets.

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Native chicken feather keratin, commercial feather meal and soluble feather keratin derivatives (keratose, keratein and carboxymethyl feather keratin) were digested by several proteases (pronase, protin, papain and pancreatin) and the digestibility was compared. The digestibility of native feather keratin and commercial feather meal was 20 and 50_??_70% respectively with all proteases tested. Pronase and pancreatin were more effective in di-gesting the soluble feather keratin derivatives than the others. However, the different reaction patterns were observed on these two enzymes. Pronase's action reached the equili-brium quickly but pancreatin's action was gradual to attain the equilibrium.

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Successful oxidations with chromic acid-sulfuric acid mixture of synthetic isomeric hex-2-en-l-ols to give trans-hex-2-en-l-al (leaf aldehyde) and the failure of those of synthetic isomeric hex-3-en-l-ols pointed out the probable contamination of the 2-enol isomer in the earlier “leaf alcohol preparation” of plant origin, which might lead the workers to an erroneous conclusion.
In support of the present worker's opinion, trans-hex-2-en-l-ol was actually isolated from fresh tea leaves and identified in the present investigation and a mechanistic rational was invoked to account for the results of oxidations of isomeric n-hexenols.

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α-Amylase formation by washed cell suspensions of Bac. subtilis was found to be accompanied by the excretion of a compound consisting of glucose, glycerol and phosphoric acid. It was excreted as a polymer and a monomer. The former, a kind of teichoic acid, was significantly dominant in quantity when the cells were incubated under the conditions suitable for α-amylase formation. On the other hand, the monomer prevailed when the bacterial cells were under the unfavorable conditions for the enzyme formation.
Both compounds were purified by ion exchange column chromatography. Chemical and enzymatic investigations revealed the following structures: 2-O-α-D-glucopyranosyl-glycerol-3-monophosphoric acid for the monomer, and a polymerized form of the monomer through phosphodiester linkages involving the hydroxyl groups on C3 of the glycerol, for the polymer.

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A mutant, KY 13171, of Brevibacterium ammoniagenes which accumulates considerable amounts of 5' inosinic acid (IMP) in the presence of excessive manganese ion (Mn²⁺) was induced from KY 13102 with which accumulation of IMP was severely inhibited by excessive amounts of Mn²⁺.
IMP accumulation by KY 13171, and the cell growth were increased as the concentration of Mn²⁺ was increased. In the presence of excessive Mn2, KY 13171 did not show cellular morphological changes, and the viable cell counts did not decrease during cultivation, resulting in accumulation of 7.5mg of IMP and 2mg of hypoxanthine per ml after 4 days cultivation at 300°C. The optimum concentration range of adenine for IMP accumulation was rather broad, 0 to 100mg per liter, and addition of more than 100mg of adenine per liter caused decrease in IMP accumulation. The cellular morphology was not affected by adenine concentration. Alkaline phosphatase activity and nucleotide degradative activity were the same as those of the parent strain, KY 13102. Intracellular nucleotide pool was the same size as that of KY 13102. Direct accumulation of IMP was observed in the cell suspension.
These results appear to indicate that KY 13171 is a new type of manganese-insensitive IMP producing strain and that the permeability barrier for excretion of IMP was changed by mutation.

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Three new labdane type diterpenes; 4-epiagathadiol (named kayadiol), 18-hydroxy-manool (named torreferol), 18-hydroxy-13-epimanool (named 13-epitorreferol), were isolated from the non-steam-volatile fraction of leaves of Torreya nucifera Sieb. et Zucc. (Taxaceae, Japanese name “Kaya”).
This is the first reported isolation these three diterpenes in natural source.

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Physicochemical and enzymatic properties of five purified isoenzymes of Japanese-radish peroxidase were investigated comparatively. The molecular weight of peroxidase was different among the acidic, neutral and basic isoenzymes, while the ordered secondary structures seemed to be essentially the same on the observation of infrared spectra. The acidic isoenzyme, No. 3, exhibited a characteristic behavior in the visible absorption spectrum, which showed a thermal interconversion between high- and low-spin states at low temperatures and also the lowest pK value of the proton dissociation to form the hydroxide compound. The basic isoenzyme, No. 16, was characteristic in its highest affinity for cyanide. In the catalytic activity, the weakly acidic isoenzyme No. 5 was the most active, exhibiting the highest rate constants both for hydrogen peroxide and for guaiacol.

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Huratoxin, [α]²⁸_D+55.1 (c=2.69, CHC1₃), a piscicidal constituent, was isolated from the sap of Hura crepitans. It was elucidated to have the formula C₃₄H₄₈O₈ and contain a 1, 3-trideca-dienyl, an isopropenyl, a secondary methyl, an α-methylcyclopentenone, an epoxide and three hydroxyl (primary, secondary and tertiary) groups. Its piscicidal activity was evaluated to be about 10 times that of rotenone.

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Purification and properties of a new alkaline protease of rat skeletal muscle have been reported. The purification procedure of the enzyme is as follows: skeletal muscle tissue was extracted successively with Hasselbach-Schneider solution, 5M urea solution and 2% sodium deoxycholate solution. After then, the enzyme was extracted from the residue with 1.1M potassium iodide solution. This enzyme solution was treated with n-butanol, and dialyzed against water. The enzyme precipitated during dialysis was collected and dissolved in 1.1M potassium iodide solution. The enzyme solution was fractionated with acetone, and chromatographed on Sephadex G-200. The final preparation showed over 20000 times of purity.
The optimum pH range of the enzyme activity is 9.5_??_10.5, and the maximum reaction rate occurs at 47_??_57°C. The enzyme is stable below 47°C at pH 7.3. At 37°C, the enzyme is stable during 30min at least, in the pH range of 5.5-10.0. Below pH 5.0, it is relatively labile. Hg²⁺, Ca²⁺, Mg²⁺, Mn²⁺, C0²⁺, and Zn²⁺ scarcely affect the enzyme activity at the concentration of 1mM. Ethylenediaminetetraacetate shows little effect on the activity at the concentration of 10mM, and iodoacetamide, 2, 4-dinitrophenol, p-chloro-mercuribenzoate show the similar effect at the concentration of 1mM. Diisopropyl-fluro-phosphate inhibits the enzyme activity. From the results obtained, this enzyme is presumed to be responsible for the activity of autolytic breakdown of rat skeletal muscle proteins in the alkaline pH range.

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Various strains of Streptomyces and Aspergillus and several commercial glycosidases were tested for activities of human blood group A and B substance degradation. Five strains of Streptomycessp. destroyed the serological activity of A substance and 2 strains of the same genus destroyed B substance. In Streptomyces 9917S₂, the strongest decomposer of B substance, the activity of B substance degradation was induced by galactose, lactose, raffinose, and melibiose. Fructose, inulin, maltose, and glucosamine also acted as inducers. Culture broth of this organism has the activities of α- and β-galactosidases and β-N-acetyl-glucosaminidase. Activities of α- and β-glucosidases, α-N-acetyl-glucosaminidase, and α- and β-N-acetyl-galactosaminidases were not detected. Characteristics of blood group substance degradation by this organism were discussed in relation to glycosidases present in this organism.

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Mode of action of crystalline nuclease 0 obtained from autolyzed Aspergillus oryzae on RNA and synthetic homopolymers was examined. Crystalline nuclease 0 had no strict base specificity, although the velocity of hydrolysis was poly A>poly U>RNA>poly C. This enzyme did not degrade poly C. Digestion of high molecular weight RNA with an excess of this enzyme produced mono-, di- and trinucleotides with 5'-terminal phosphate. The amount of mono-, di- and trinucleotides was, respectively, 13.6, 70.0 and 16.4% of total degradation products. All the four bases were detected in mononucleotide fraction and 3'-terminals and 5'-terminals of oligonucleotides.

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A new and convenient non-stereoselective synthetic route to the C₁₈-Cecropia juvenile hormone (as a stereoisomeric mixture) was developed. Employing this method, several juvenile hormone analogues with various alkyl groups at the terminal position were synthesized as stereoisomeric mixtures. Two analogues with two ethyl groups or n-propyl and methyl groups at the terminal position were more active than the C₁₈-Cecropia juvenile hormone onTenebrio molitor and Tribolium castaneum.

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α-Amylase was purified from a culture of Aspergillus oryzae on steamed rice by means of ion exchange chromatography on DEAE-Sephadex, and the purified enzyme was crystallized with ammonium sulfate. The preparation was found to be homogeneous by means of sedimentation and disc electrophoretic analyses. The enzyme was revealed to have strong α-amylase activity by the dinitrosalicylate method and the iodine color method. Large single crystals of the enzyme were prepared by making the concentrated enzyrr.e solution to 0.41 saturation of ammonium sulfate at pH 5.0. A brief communication on the preliminary X-ray crystallography was also presented.

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The in vitro action of Taphrina wiesneri on coumarin and its related compounds were examined. Melilotic acid, which accumulates in larger amounts in infected cherry leaves than in healthy leaves, was produced from coumarin, 3, 4-dihydrocoumarin, o-coumaric acid or o-coumaryl glucoside by the action of acetone-dried cells of the fungus. From the results it is suggested that in cherry plants infected with the fungus melilotic acid may be formed from these precursors contained as ordinary components in cherry leaves. Possible mechanisms of the conversion of coumarin to melilotic acid are also discussed.

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