The nucleoside phosphotransferase of Escherichia coli was partially purified by the ammonium sulfate fractionation and acid precipitation and confirmed to synthesize mainly 3'(& 2')-inosinic acid together with a small amount of 5'-isomer from inosine and p-nitrophenylphosphate.
The optimum pH of this reaction was found to be at the pH of around 5.0.
The efficiency of this phosphate transfer reaction is the functions of the kind of phosphate donor and of the concentration of acceptor and donor. p-Nitrophenylphosphate was the most excellent donor for this reaction.
From the results of experiments using inhibitors or metallic ions, it appeared that cupric ion and zinc ion affected on the nucleoside phosphotransferase, especially the former accelerated both IMP synthesis and liberation of p-NP, and it was discussed that the nucleoside phosphotransferase may be differnet from the phosphatase.

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The distribution of nucleoside phosphotransferase activities in bacteria was studied in the acidic reaction mixture containing HxR and a phosphate compound such as p-NPP, and the activities were found to be distributed in various kinds of bacteria, most of which are grouped in Gram-negative bacteria.
The bacteria which can synthesize nucleotides by their nucleoside phosphotransferases were divided into two groups, depending on the kind of synthesized nucleotide isomers and the donor specificity.
The bacteria which were characterized to catalyze mainly the phosphorylation at 5'-position of nucleoside were found in such genera as Pseudomonas, Alcaligenes, Achromobacter, Flavobacterium, Serratia and Staphylococcus, while the bacterial strains assigned to such genera as Aeromonas, Escherichia, Aerobacter, Proteus and Salmonella were characterized to predominantly catalyze the phosphorylation at 3'(& 2')-position.
When the nucleotides were used as phosphate donors, their phosphate group was specifically transferred to the same position of the nucleotide which were produced by the bacteria, either in the intact cell system or in the cell-free systems.
These specificities of nucleoside phosphotransferase were considered to be correlated with the classification of these bacteria.

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1) A newly isolated bacterium, strain S-48, having mannose isomerase was named Xanthomonas rubrilineans S-48.
2) The mannose isomerase activities of bacteria belonging to Xanthomonas were investigated. The enzyme was found to be in all the Xanthomonas species examined and was strongly produced by Xanthomonas oryzae IAM 281-1 and Xanthomonas pruni IAM 281-5. The enzyme of these bacteria was formed constitutively.

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Crude mannose isomerase preparation from Xanthomonas rubrilineans S-48 which converts D-mannose to D-fructose was further purified by ammonium sulfate fractionation and DEAE-cellulose column chromatography. The specific activity of the purified enzyme solution was about 35-fold of original crude preparation. By using this purified enzyme solution, several enzymatic properties were investigated.
(1) The Michaelis constant was 1.2×10^-2M. (2) The enzyme was sensitive against temperature, but Ca⁺⁺ protected the enzyme to some extent from the effect of temperature. (3) The enzyme was stable in the pH range from 6 to 9. (4) The enzyme was not inhibited by glucose, xylose, mannitol, sorbitol, mannonic acid, mannuronic acid and so on, but strongly inhibited by D-arabinose and L-fucose, and Ki values of these inhibitors were 1.1×10^-2M and 7.1×10^-4M respectively.

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The saturated and unsaturated fatty acids of the algae Chlorella and Scenedesmus were examined by paper chromatography, alkali isomerization and gas chromatography. Free fatty acid obtained by saponificaton was about one half in amount of the total lipid. The solid fatty acid amounting to about 13% of the total fatty acid was found to be palmitic acid. Linolenic acid was nearly 40%, while the sum of stearic acid and oleic acid was less than 4%. Tetraenoic acid was found to be present in all the samples used in this experiment. Tetraenoic acid of Chlorella was found to be C₁₆-acid and amounted to 15_??_26%, though it was not found in C₁₈-acid. Hexadecamonoenoic acid was about 10% and it was separated by column chromatography using a silica gel: Celite (2:1) column. Its double bond was found to be at the 3 position, because tridecanal was the product of its ozonide cleavage.

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It was found that muramidase can catalyze the hydrolysis of p-nitrophenylacetate (NPA) producing p-nitrophenol and acetic acid. The activity of muramidase for NPA, however, simply increased on raising a temperature and with an increase in alkalinity of reaction mixture. The mechanism of muramidase catalyzed hydrolysis of NPA differs from that of chymotrypsin which can catalyze burstly the hydrolysis of NPA by its histsdine residue.
The amount of reducing power produced owing to the hydrolysis of glycol chitin by muramidase was not affected by the presence of NPA, and inversely, the hydrolysis of NPA was not affected by glycol chitin. Obviously, there was no competitive inhibition between NPA and glycol chitin. The responses of modified muramidase to glycol chitin and to NPA did not correspond at all. The catalytic site of muramidase for glycol chitin may be different from that of muramidase for NPA. The hydrolysis of NPA is catalyzed by some free amino groups in the muramidase molecule, while the catalytic site for glycol chitin is not known.

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The presence of γ-L-glutamyl-S-methyl-L-cysteine in kidney beans (Phaseolus vulgaris L.) and lima beans (Phaseolus limensis Macted.) has been reported by several investigators. Thompson et al. have prepared this peptide from S-methylglutathione by the carboxy peptidase method. In this report a new and different method of synthesis of γ-L-glutamyl-S-methyl-L-cysteine is described. The peptide was confirmed by elemental analysis, melting point, and paper chromatography. The infrared spectrum of this compound was identical with those of the authentic samples from Phaseolus vulgaris and S-methyl glutathione.

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Pectic acids were not completely hydrolyzed with the preparation of carrot exopolygalacturonase, purified about 280-fold. The degradation limit was found to vary over a wide range according to the source of pectic acid. The value for degradation limit was 56.1% for pectic acid from bast of ramie, whereas it was 6.7% for that from peach flesh.

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Piperonylic acid and its higher homologues homologues were esterified with (±)-cis-chrysanthemol, (±)-trans-chrysanthemol, (±)-allethrolone and piperonyl alcohol. The toxicities of the esters against common house fly, Musca domestica vicina Macq., were tested by the topical application method. Three of the esters (entry Nos. 1, 2 and 3) were shown to be slightly toxic. However, further elongation of the ester linkage by methylene groups reduced the biological activity.

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Exopolygalacturonase from Coniothyrium diplodiella has been purified by ammonium sulfate fractionation, chromatography on DEAE-cellulose and column zone electrophoresis. The enzyme was concentrated about 5-fold with a yield of 0.24% on the basis of polygalacturonase activity per weight of total nitrogen. The purified enzyme was homogenous on free-boundary electrophoresis. The enzyme was most active in the pH range 4.0_??_4.5. The enzyme was stable at 50°C and pH range of 3.5_??_6.0, but inactivated at higher than 55°C. Hydrolysis of pectic acid by the enzyme went to completion via galacturonic acid liberation from the end of the chain, but pectin was little affected by the enzyme.

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A new crystalline form of monosodium L-glutamate, which is different from the known monosodium L-glutamate monohydrate crystal in external appearance, density, X-ray diffraction pattern, solubility, and water of crystallization, has been crystallized from ca. 73 weight per cent aqueous methanol solution at ca. 18°C. It was identified as the dihydrate from the determination of water of crystallization based on Karl Fischer's method. The newly found crystals are extremely unstable in air, aqueous solution, and the mother liquor, because of rapid transformation into the stable monohydrate, whereas they can be kept in a considerably stable condition in absolute ethanol and acetone.

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The presence of several diketopiperazines including L-tyrosyl-L-proline anhydride was confirmed in peptone by means of thin layer- and gas-chromatography.

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