Oxidation of pyridoxine-P and pyridoxamine-P to pyridoxal-P, inhibition and reacti-vation of the oxidases were investigated, using the Alcaligenes faecalis oxidase and the Azotobacter agilis oxidase catalyzing. Zone electrophoretic experiments indicated that the oxidases obtained from Alcaligenes faecalis andAzotobacter agilis moved to cathode and anode, respectively, under the same conditions. The oxidation-reduction potential of the both oxidase was found to be about -50 mV. The oxidation of both pyridoxine-P and pyridoxamine-P was strongly inhibited by pyridoxal-P, pyridoxal, pyridine-4-aldehyde and 4-pyridoxic acid phosphate. This inhibition was markedly decreased by Tris-HCI buffer, and other amino compounds that form Schiff's base of pyridoxal-P.

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An enzyme “pyridoxamine-P transaminase” which catalyzed the transamination bet-ween pyridoxamine-P and α-ketoglutaric acid was found in certain anaerobic bacteria, such as Clostridium acetobutylicum, Cl. kainantoi, Cl. kaneboi and Cl. butyricum. The pyrido-xamine-P transaminase in the cell-free extract of Cl. kainantoi was purified and some pro-perties were investigated. α-Ketoglutaric acid appeared to be the dominant amino acceptor. Pyridoxamine-P was found to be active as amino donor, but other amino compounds were inert. Since the results were inconclusive, the possibility of vitamin B₆-enzyme of pyri-doxamine-P transaminase was not shown by the inhibitor studies. Physiological role of the pyridoxamine-P transaminase was discussed in the relation to vitamin B₆ metabolism in anaerobic bacteria.

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The action pattern of β-amylase on amylose was studied by the amperometric titration with iodine. Partially hydrolyzed amylose with the degree of polymerization about 150 was hydrolyzed by crystalline sweet potato βamylase at 35°C and pH 4.8. Aliquots of the reaction mixture were taken at various time intervals during β-amylolysis, and subjected to amperometric titration. Amperograms showed that electric currents at the horizontal segments in titration curves were increased as the substrate was hydrolyzed by the enzyme. Results indicated that the β-amylase is operating by a multi-chain mechanism.

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When the ‘dihydroxyacetone-fermentation’ was carried out in a steady state by the cells ofBr. fuscum, it was suggested that the consumption rate of glucose in the medium might be regulated at the initial stages of glucose degradation such as; (a) glucose isomeri-zation, (b) glucose dehydrogenation, and (c) glucose phosphorylation. Of these three enzymatic reactions, the isomerization and the dehydrogenation were proved to be unable to occur or negligible in vivo. So, in consideration of the pool sizes of Mg⁺⁺, Pi, H⁺, glucose, G6P^*, ATP, ADP, etc., the intracellular glucokinase^** activity was calculated. Results indicate that glucokinase reaction may be the limiting factor for direct glucose metabolism in Br. fuscum.

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Methylation of hot-water-extract fraction of soybean seed polysaccharides by the Haworth's method and then by the Purdie's method followed by fractional extraction afforded a fully methylated arabinogalactan which gave on complete hydrolysis 2, 3, 5-tri-, and 2, 3-di-O-methyl L-arabinose and 2, 3, 6-tri-, and 2, 6-di-O-methyl D-galactose in the approximate proportion of 1:1:3_??_4:1, and on controlled acid methanolysis 2, 3, 5-tri-, and 2, 3-di-O-methyl L-arabinose in about equal proportion. Residual undegraded poly-saccharide gave mainly 2, 3, 6-tri-O-methyl D-galactose on remethylation and hydrolysis.

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D-galactose was incompletely methylated with methyl sulphate and sodium hydroxide, and two trimethylgalactoses were chromatographically separated from the products. Gas-liquid chromatographic examination, periodate oxidation and melting points of them or their suitable derivatives showed that one of them was 2, 3, 6-tri-O-methyl D-galactose, and the other was presumed to be 2, 4, 6-tri-O-methyl D-galactose. For confirmation of 2, 3, 6-tri-O-methyl D-galactose, 2, 3-di-O-methyl L-threose and its aldonophenylhydrazide were prepared from 2, 3-di-O-methyl L-arabinose as authentic sample.

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The RNase (EC 2.7.7.16) in bovine milk was partially purified from milk whey. The basic properties and the hydrolyzing specificity of this enzyme were studied. This enzyme was heat stable. When RNA was used as the substrate, the pH optimum was 7.5 and 3'-nucleotides were produced, but the extent of the hydrolysis stopped at 31 per cent and core was left. C! and U! were hydrolyzed but purine cyclic nucleotides were not. Poly U was digested to 3'-uridylic acid passing through U! but poly A was not. These pro-perties are quite similar to pancreatic RNase.

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Ipomeamarone inhibited oxidation and phosphorylation in tightly coupled rat liver mitochondria. The inhibition of the oxygen uptake was higher when either β-hydroxy-butyrate or α-ketoglutarate was supplied as the substrate than when succinate was used. In mitochondrial preparations which had been uncoupled, inhibitions of the electron transport chain from β-hydroxybutyrate to cytochrome c, and of the enzymes succinate cytochrome c oxidoreductase and β-hydroxybutyrate dehydrogenase were observed. Ipome-amarone inhibited also the ATP-inorganic phosphate exchange reaction, but did not act as an uncoupler; it repressed 2, 4-dinitrophenol-induced oxygen uptake.

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A procedure for obtaining crystalline preparations of the amine oxidase of Aspergillus niger has been developed. The method involved fractionations with ammonium sulfate and separation on successive columns of DEAE-cellulose, DEAE-sephadex and hydroxyl-apatite. Crystals were formed when solid ammonium sulfate was added to solutions of the purified enzyme (of about 300- to 350-times the specific activity of the crude mycelium extract). The crystals appeared as fine rods, with a faint pink color. The crystals had a specific activity around 10, 000 which was about 20 times as active as that of crystalline preparations of the animal monoamine oxidase.

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2, 2-Dimethyl-3-isopropylcyclopropyl propionate, which Jacobson claimed to have synthesized in 1963 as the dihydro-derivative of the sex attractant of cockroach, was re-examined. The oxidation of ethyl 2, 2-dimethyl-3-isopropylcyclopropyl ketone by using trifluoroperacetic acid as oxidant afforded the desired ester.

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2-Propyl-5-ethyl-benzylalcohol (IX) was synthesized by an unequivocal route from propylbenzene, thereby establishing the previous deduction tentatively assigned to the leaf alcohol reaction product.¹⁾ This benzyl alcohol surmises one of a lemon-like flavor charac-teristic of manufactured black tea and an attempted search for this compound in the essen-tial oil obtained by steamdistillation of manufactured black tea was made, but its existence has not so far been confirmed with a neutral fraction examined.

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To keep an enzyme stable in solution, the stabilities of the enzyme in various poly-hydric alcohols were investigated, and it was found that the enzyme in 70% aqueous sorbitol solution was strikingly stable against both storage at 33°C and heating at 80°C. It seems reasonable to ascribe this stability to such high osmotic pressure of the sorbitol concentration that decreased the viable counts of microorganisms. The reason why the sorbitol is the most effective among various polyhydric alcohols is now being investigated. This stable enzyme solution will be of good advantage as food improver, medicines or so on.

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1.Itwasconfirmed that washedyeastcellsproducedisobutanolandisoamylalcoholfrom pyruvic acid or α-ketoisovaleric acid.
2. These results strengthen the reliability of the postulated scheme of the formation of these two alcohols from puruvic acid proposed by us.
3. Effect of aeration, pH and leucine and ammonium chloride added in the fermenting medium on the formation of isobutanol and isoamyl alcohol was examined.

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Two β-glucans were prepared from the aqueous extract of the endosperm of naked barley. The extraction was carried out under conditions which obviated enzyme action and eliminated the contamination of starch fraction. The precipitate obtained with 20% concentration of ammonium sulfate of the extract was adsorbed on DEAF-cellulose (borate form) column and fractionated into two fractions by the elutions with H₂0 and 0.5 N NaOH, respectively. From 5 kg. of the endosperm the yield of the former was 13.3g. (0.27% of the endosperm), the latter was 2.0g. (0.04%). Both showed only one peak ultracentrifugally, were slightly levorotatory, not degraded with α-amylase, and consisted of only D-glucose. These data suggest that they are both β-glucans.
β-Glucan consumed in periodate oxidation 0.74 mole periodate per 1 mole of anhydro-glucose. Hydrolysate of the methylated j3-glucan gave 2, 3, 6-tri-O-methyl-D-glucose and 2, 4, 6-tri-O-methyl-D-glucose, and methanolysate of the methylated Q-glucan gave methyl 2, 3, 6-tri-O-methyl-β-D-glucopyranoside and methyl 2, 4, 6-tri-O-methyl-β-D-glucopyranoside, although α-anomers were not separated. From sedimentation and diffusion coefficients the molecular weight of the β-glucan was calculated as 220, 000.
These results indicated that the β-glucan was consisted of β-1, 4 and β-1, 3 linked glucopyranose residues with proportions of 2.5:1 to 3:1 (β-1, 4 linkage to be predominant) and that the β-glucan had a linear structure.

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Two acid-proteases, shown previously to be present in Takadiastase and tentatively named as SE- and DEAE-protease, were purified. These two enzymes did not differ in enzymatic properties investigated but differed in some physical properties, such as iso-electric points.
Though the SE-protease showed only a single peak in ultracentrifugal sedimentation patterns, it was separated into two or three components in electrophoretic patterns. On the contrary, the DEAE-protease showed only a single peak in either sedimentation patterns or electrophoretic patterns.

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