(1) Fractionation of the plant enzyme proteins obtained from Squash rind juice was carried out by partial precipitation with ammonium sulfate, from which it was completely revealed that the plant L-glutamic acid decarboxylase preparation as reported in many papers may consist of α-ketoglutaric-γ-aminobutyric transaminase and L-glutamic acid decarboxylase.
(2) Further stereochemical evidence of L-glutamic acid was obtained by paper partition chromatography and by paper electrophoresis, and the L-glutamic acid formed by this transaminase was proved to be of the L-form configuration.
(3) The preparation containing transaminase obtained here was tested for its activity of L-glutamic acid formation from α-ketoglutaric acid and ammonium sulfate, and always gave negative results.
The expence of this research was partly defrayed by a grant in acid from the Ajinomoto Co., Inc., to which the authors' thanks are due. The authors also wish to thank Messrs. T. Miki, N. Tsukada, M. Matsumoto of this laboratory for their generous assistance.

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(1) Proteinase activities in the soy mash juice were measured by a modification of the Anson method, and compared with those of the purely cultured soy koji digest which contained only Aspergillus proteinases.
(2) The pH-activity curves, the inhibition by specific inhibitors, acid and alkali treatments showed that the proteinases in the soy mash were almost of Aspergillus origin. Detection of bacterial proteinases was unsuccessful.
(3) The existence of a specific inhibitor was recognized in the soy mash of Aspergillus sojae strain KS, which inhibits Aspergillus proteinase, specifically at pH 8.
(4) The two peaks of activities of Aspergillus Alkaline Proteinase at pH 10.0 and at pH 7.0 had a different liberation ratio of phenolic amino acids. In some cases, the inhibition of soy mash proteinase was observed at pH 10.0 but not at pH 7.0.
(5) Bacterial viable counts of soy mash juice was not changed by heat shock. The vegetative cells of Bacilli were difficult to observe under the microscope. It is therefore considered that most of the Bacilli survive in the form of spores which had been produced in the stage of koji making, and that there are very few Bacilli growing in the soy mash.

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Thirteen strains of salt tolerant specific lactic acid bacteria were isolated from soy sauce brewing mashes, and their taxonomical characteristics investigated. These strains are spherically shaped, generally assume a tetrad form, micoaerophilic, and perform the homo-type fermentation. Eleven strains produce d-lactic and two other strains produce dl+(d) lactic acid. These characters are unaffected even when grown in salted broth containing 15% sodium chloride. They grow well in a medium containing 18% salt, and the upper limit of the salt tolerancy is approximately between 24 to 26% sodium chloride. The salt tolerant capacity seems to be a hereditable character. The strains grow within a pH range between 5.5 to 9.0, but no growth is observed at pH 5.0. The optimal temperature was from 20°C_??_30°C. Many sugars are well fermented, and this ability was not diminished in 17% salted media.
From these facts, the author proposed the name Pediococcus soyae nov. sp. for this sort of organism.
This bacteria requires two specific nutrients: namely, a peptide-like substance (P-factor) included in the “Polypepton” (Takeda) and a dialyzable unknown substance (S-factor) included in the “Heart infusion broth”, “Yeast extract” and “Beef extract” (Difco). This bacteria do not require leucovorin.

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In order to establish a synchronized state of bakers' yeast cells, environmental conditions suitable for budding and cell division were examined. It was observed that budding did not occur below a certain level of feed rate in aerated flow culture, and, this level somewhat increased at a higher temperature. In the low feed rate, separation of daughter cells from the mother cells was not significantly influenced by temperature with aeration, while it proceeded more rapidly at a higher temperature with shaking. The conclusion is that the separation of daughter cells is influenced not only by physiological conditions but also by mechanical conditions. At 35°C, however, the secondary budding took place after budded cells had divided, even at the level of feed rate, under which the budding of rest-cells could not have occurred. A preliminary treatment for synchronization was then devised, and it was concluded that the present treatment for synchronization is due to a process of slight growth, not being due to starvasion.

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Many strains of genus Acetobacter were isolated and collected from the various habitats, and twenty strains were selected for present study. Three new species and one variant were detected.
The oxidizabilities of the resting cells for various substrates were measured by the manometric method. Thus, two groups were observed in the species.

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(1) The oxidative activities on glucose, gluconate, 2-ketogluconate, and 5-ketogluconate by resting cells of Acetobacter were measured manometrically.
(2) The effect of 2, 4-dinitrophenol on oxi-dations was observed and it was found that Acetobacter species is classified into four types.
(3) The effect of pH on the oxidation was observed and discussed.

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Development of oxidation products from glucose by growing A. melanogenum was observed. A penturonic acid-like compound, one of the main products, was isolated and identified with D-lyxuronic acid. D-Lyxuronic acid was isolated as crystallized and lyophilized calcium salt. [a]n of the calcium salt was -23°, and showed mutarotation. It had a furanose ring structure in solid phase. It consumed three moles of periodate per mole and was then divided into glyoxylic and formic acids. It was discussed that D-lyxuronic acid was produced from 2, 5-diketogluconic acid, with decarboxylation of the first carbon, via probably 4-ketoarabinose and 4-ketoarabonic acid. In the oxidative products, phosphate ester compounds were not detected.

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The nitrate reduction of the mouse liver homogenate was inhibited by several purines which have free-N at the positions of 1, 3, and 7, such as adenine, guanine, hypoxanthine, xanthine, 6-mercaptopurine, 8-azaguanine and 8-azaxanthine. Since the liver contains xanthine oxidase, the decoloration of methylene blue was promoted by hypoxanthine and xanthine, and it was delayed by other purines. On the contrary, caffeine and theophylline, N-methyl derivatives of purine were not effective or less effective in inhibiting the reduction of methylene blue as well as nitrate. The relation between nitrate reduction and the xanthine oxidase was presumed.

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Higher homologous acids of chrysanthemic acid described in the previous papers were esterified with (±)-allethrolone. The toxicity of these esters and the related compounds were evaluated by the topical application method to Musca domestica vicina Macq. The allethronyl homochry-santhemate (entry Nos. 4, 5) was shown to be toxic and the dextrorotatory form was far more toxic than the laevorotatory one. Further elongation of the ester linkage resulted in a loss of toxicity. The cyclobutane carboxylic acid ester (entry No. 10) was shown to be toxic and so, the cyclopropane ring might be replaced to some extent by the cyclobutane ring, provided the other requirements were fulfiled. However, further elongation of the ester linkage also reduced the toxicity. The lactones (entry Nos. 12-16) obtained by the hot sulfuric acid treatment were non-toxic.

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It has been reported by several persons, including one of the authors, that DPNH obtained by the electrolytic reduction at controlled potentials is not fully active in respect to the reaction with alcohol dehydrogenase system. But statements concening the percentage of activity and the conditions which affect the activity were not identical. This article deals with these problems by reducing DPN electrolytically under different conditions followed by enzymatic examinations. The electrolytic reductions of TPN and cytochrome c were also performed. Though the data presented are rather complicated, the most active DPNH was prepared in tripolyphosphate buffer with platinum electrode at -2.Ovolt vs. S. C. E., under ice-cooling. The effects of phosphates and electrolytic potential are discussed.

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Although the electrolytically obtained DPNH was not completely oxidized by usual dehydro-genases or diaphorases, one of the authors noticed that its absorption band at 340mμ disappeared completely when it was incubated with the extract of mung been seedlings. The reaction was found to be stimulated by the addition of methylene blue, and the product was identified as DPN. Thus, the reaction resembled that of diaphorase, although it was less specific to the configuration of DPNH. But unlike usual diaphorase, it required a cofactor, which was neither flavins nor metallic ion, but an unidentified acidic substance. General properties of the enzyme and the cofactor are reported in this article.

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Assimilation of nitrogen by nitrogen-deficient Chlorella cells was investigated. Assimilation occurred very actively at first in the dark, and almost entirely stopped within a few hours, during which remarkable decreases in free reducing sugar, sucrose and water-soluble polysaccharide in the cells were observed. Most of the nitrogen assimilated was stored as soluble nitrogen. Assimilation of nitrogen was accom-panied with the activation of respiration and photosynthesis. Activation of respiration ceased when the nitrogen was completely absorbed, but that of photosynthesis lasted thereafter. The latter resulted in stimulation of growth, and favoured very much the operation of semi-continuous and continuous cultivations of nitrogen-deficient fatty cells. It was as-certained that these cultivations can be continued for a certain length of time with much better yield of fat than expected owing to the activation of growth, though the fat content of cells shows a slightly decreasing trend in the course of the operation in the state of equilibrium. The stimulation of photosynthesis was considered to be due to the activation of the enzymes or the enzyme systems involved in the carbon dioxide fixation mechanism.

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Participation degree of photosynthesis and respiration in fat synthesis in Chlorella in nitrogen-deficient growth was investigated with the medium of photosynthetic and respiratory quotients. It became clear that photosynthesis is mainly responsible for fat formation at least in the early stage of nitrogen deficiency and the reducing power resulting from light energy can be directly utilized for fat synthesis together with that released from carbohydrate through respiration.
The rate of respiration per unit weight of cell nitrogen showed a remarkable increase with the advance of nitrogen deficiency. This fact strongly suggests that reorganization of nitrogen compounds occurs during the nitrogen-deficient growth.
The effect of dark respiration on the accumulation degree of fat was investigated in relation to the practical nocturnal effect in the outdoor culture for fat production. It was clarified that dark periods give a favourable effect on both growth and fat formation, especially in the growing stage. But it became clear that the amount of fat cannot be increased in a large quantity by converting the accumulated carbohydrate through respiration in a prolonged dark period.

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