1. The amount of cholesterol, cerebroside, total phospholipid and the constituents (i.e. lecithin, cephalin and sphingomyelin) contained in the four parts of the central nervous system (i.e. cerebrum, cerebellum, brain stem, and spinal cord) was determined in the ox, rabbit and hen and that contained in the whole brain in the snake, frog and mackerel.
2. The ox cerebrum was separated into the white and the grey matter for the analysis of the above-named substances contained in each part.
3. In the rabbit and hen, the spinal cord was found to contain cholesterol, cerebroside and total phospholipid in higher concentration than other parts of their brain.
4. Cephalin occupies the largest proportion of total phospholipid in any species of animals and in any part of the brain studied.
5. In the ox brain various lipids were contained in greater concentration in the white matter than in the grey, but the difference of lecithin content between them is not so remarkable than that of other lipids.
6. The relative concentration of cholesterol and cerebroside, as determined on the basis of “essential lipid, ” was greater in the white matter than in the grey, but quite the contrary was the case with that of phospholipids.
The author is indebted to Dr. R. Hirohata, Professor of the Department of Medical Chemistry and Dr. S. Naka, Professor of the Department of Neuropsychiatry, Faculty of Medicine, Kyushu University, for their valuable advices and encouragements during this work.

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For the characterization of a sucrase in Takadiastase, the ratio of the activities on sucrose, raffinose, and inulin was determined at the substrate concentration of 10 per cent (w./v.). The ratio of the activities on these three substrates remained almost constant even when Takadiastase was subjected to various treatments. The results suggested that there was a single transfructosidase attacking these three substrates in Takadiastase.
The author is very grateful to Prof. Shin'ichi Shibuya for his kind encouragement and advice. This work was aided by the Scientific Research Funds from the Ministry of Education, to which the author gave thanks.

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1. Gentisic acid was isolated in crystalline form from homogentisic acid by reaction with liver extract of the rabbit in the presence of nitroso-R salt.
2. When nitroso-R salt was injected intraperitoneally in the tyrosine fed rabbit, homogentisic acid and gentisic acid were detected in the urine by means of paperchromatography.

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1. To clarify the conversion of phenylalanine to tyrosine in the silkworm, isotopic phenylalanine-2-C¹⁴ was injected into the silkworm body at the 5th stage, and the radioactivity of tyrosine isolated from the produced cocoon fibres was detected.
2. Tyrosine, being one of the main constituent amino acids of the silkprotein, is synthesized from phenylalanine in the silkworm body and then is used for the biosynthesis of the silkproteins.

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High concentrations of polyethylene glycol markedly increase amylase production by Bacillus subtilis H. Polyethylene glycol is not oxidized by this bacterium and its effect seems to be physicochemical, similar to its action in the formation of protoplasts, described in a previous paper.
From these, and many other experimental results obtained previously, the following explanation was proposed: Amylase production is a kind of abnormal biosynthesis occurring in the old cells in which normal cellular multiplication no longer takes place. When cells are producing amylase they are unstable and highly susceptible to rapid autolysis. They undergo rapid lysis anaerobically, and lyse gradually in shaken cultures. A high concentration of a suitable substance, such as polyethylene glycol or starch, either stabilizes these cells, or maintains this abnormal, unstable state, and prolongs the period of active amylase production, thus displaying remarkable activating effect on the total amylase production.

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1. Adenosine-5'-monosulfate (AMS) and riboflavin-monosulfate (FMS) compete with FAD and inhibit the oxidative deamination of D-alanine by D-amino-acid oxidase.
2. The dissociation constants of AMS and FMS for the enzyme protein at pH 8.1 and 37° were evaluated as 3.12×10^-3M and 3.15×10^-5M respectively.
3. When AMS and FMS coexist, they compete with FAD, but not each other as expected and shown in Fig. 1.
4. When AMS and FMS coexist on an oxidase protein molecule, it seems an interaction to take place so that the affinities between the oxidase protein and the inhibitors may increase.
We wish to thank Miss M. Naoi, Mr. T. Ozawa and Mr. K. Okada for their kind assistance.

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By the use of the method described in the present paper, it became possible to follow up quantitatively the reaction process of the for-mation of verdohemoglobin from hemoglobin or myoglobin through an intermediate choleglobin. The following summarizes the present investigation.
1. The decomposition of myoglobin is promoted by the addition of perturbators as in the case of hemoglobin reaction.
2. The molecular extinction coefficient of verdoheme was determined as ε⁷⁶⁰_mM=1.7×10⁴, in the state of alkali-denatured globin verdohemochrome.
3. The formation of verdoheme and the yield in biliverdin were found to increase with reaction time in parallel.
4. The reaction of verdohemoglobin formation from myoglobin is promoted by increasing concentrations of ascorbic acid added. In the present reaction, 80-100 moles of ascorbic acid was consumed per mole of myoglobin-heme decomposed.
5. Some side-reactions occur after a longer reaction time.
6. The formation of choleglobin-b during the reaction of verdohemoglobin formation starting from hemoglobin increases when perturbators such as benzoate is present in the reaction system. Accordingly, the formation of verdoheme and consequently the yield in biliverdin were found to decrease in the system mentioned.
The present work was aided by the Grant in Aid for Scientific Research from the Ministry of Education, for which our gratitude is due.

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1. The conversion of fatty acids to the corresponding hydroxamic acid was demonstrated with crude extract from Mycobacterium tuberculosis avium (strain Takeo).
2. Of the acids serving as substrates for this enzyme, straight saturated butyric and valeric, dicarboxylic sebacic, and unsaturated oleic acids were the most effective. Marginal formation of hydroxamic acid was observed with formic, glycolic, glyoxylic, pelargonic, caprinic, capronic, glutaric, adipic, and pimelic acids, and with several amino acids.
3. The hydroxamic acid formation is strongly supported by the present data as the carboxyl activation. It is also evident that this formation is not esterase-, amidase-, or transpeptidase-catalyzed reaction.
4. All the results summarized in the present study can be explained by the following reactions:
Fatty acid+labile phosphate (protein bound)→(acyl-phosphate intermediate)NH₂OH→hydroxamic acid.
The detailed function of protein bound labile phosphate remains to be clarified.
The authors are indebted to Mr. H. Katayama and Mr. J. Tobari for technical assistance, and to Prof. Dr. S. Akabori for his valuable advice and encouragement during the cource of this study.

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N-Methyl-L-phenylalanine containing C¹⁴ in the methyl group was synthesized in order to trace the fate of formaldehyde liberated from it by demethylase in the rabbit body.
One g. of the synthetized compound was given to a rabbit (800g.). Within 24 hours 47.27 per cent of the methyl group administered was oxidized to carbon dioxide and expired.
There remained still 14.25 per cent of the substance in the body 24 hours afterwards, participating in transmethylation reactions and forming creatine, choline and methionine.
A part of formaldehyde was likely to take part in the formation of purine and histidine in the rabbit body.
(The author wishes to thank Prof. Dr. R. Hirohata for his encouragement and advice throughout the present work. This work was carried out by the aid of a grant from the Scientific Research Funds of the Ministry of Education.)

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Amino acid contents of crystalline phycoerythrin and phycocyanin from Porphyra tenera were determined by column-chromatographies using ion exchange resin Dowex-50 and Dowex-2. It was found that 17 common amino acids are present in these two chromoproteins and their amide N contents are very high.
The author wishes to express her gratefulness to Prof. S. Akabori for his interest and encouragement throughout this investigation and to Mr. H. Hanafusa for his valuable suggestions and technical help.

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1. In extending our previous studies a number of hydroxy compounds were tested for their acceptor function in the enzymatic transglycosylation using β-glucosidase and β-galactosidase preparations from elder (Sambucus Sieboldiana) leaves and apricot emulsin.
2. It was found that most of aliphatic alcohols were able to act as the acceptor of β-glucosyl and β-galactosyl groups, while lactate and malate were inactive in this reaction.
3. In respect of either β-glucosidase or β-galactosidase the efficiency of various alcohols as acceptor in the transglycosylation differred between the enzyme of elder leaves and that of apricot emulsin, indicating that the acceptor specificity of the enzyme catalyzing transglycosylation may differ with the source of the enzyme.
The author wishes to express his sincere thanks to Professor T. Miwa for constant encouragement and guidance while this work was being pursued.
The present work was supported in part by a grant in Aid for Fundamental Scientific Research given to T. Miwa from the Ministry of Education.

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1. Ribonucleoprotein was isolated from the silkgland of silkworm (Bombyx mori, L.) in the 5th day of the 5th instar.
2. The amino acid composition of the ribonucleoprotein was analyzed by chemical or quantitative paperchromatographical methods, and compared with that of silk fibroin.
3. Little similarity between the amino acid compositions of the two proteins was observed.
4. N-Terminal amino acid residues of the ribonucleoprotein were shown qualitatively to be occupied by glycine, alanine and serine, and this is similar to fibroin.

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Among the eight strains of aerobic bacteria tested, two strains of Serratia marcescens and one strain of Pseudomonas luorescens were found to show rapid growth in a nitrate-containing nutrient broth medium under strictly anaerobic conditions. The other five strains, which are Bacillus subtilis (2 strains), Bacillus mvcoides (2 strains), and one strain of Pseudomonas fluorescens showed no growth in the same medium under the same conditions. The latter group of bacteria, however, grew well and produced appreciable amount of nitrite in a nitrate medium under aerobic conditions, suggesting the existence of a nitrate activating enzyme system. These results might be explained by the multifunctional nature of the nitrate reductase system in microorganisms.
Some properties of the nitrate reducing systems in Serratia and Pseudomonas, which showed typical nitrate respiration, were investigated. Resting cells of Serratia reduced nitrate to nitrite in the presence of either glucose or leuco methylene blue as an electron donor. On the other hand, Pseudomonas cells reduced nitrate as well as nitrite in the presence of formate but not of leuco methylene blue as a hydrogen donor. In both the Serratia and Pseudomonas systems, the nitrate reducing activity is sensitive to metal chelating agents, suggesting a metalic component in these systems.
Phosphorus turnover in resting cells of E. coli, which also showed nitrate respiration, was greatly enhanced by the addition of nitrate and formate under anaerobic conditions. When either formate or nitrate was omitted from the system, the rate of turnover significantly decreased. The results, though indirect, may suggest the occurrence of coupled phosphorylation to the electron transport system between formic dehydrogenese and nitrate reductase.

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Two hemichromes, obtained by addition of benzoate and sodium dodecvl sulfate, react with cyanide according to the following equations, respectively.
Based on these results, some discussions were made on the interrelation between the structural modifications of globin part and the affinity of globin-N group toward heme Fe.
The present investigation was supported by Prof. K. Kaziro, to whom the author's deep gratitude is due. I should like to express my thanks to Dr. G. Kikuchi for his helpful discussion during the course of this work. The author thanks also to the Ministry of Education for the Grant in Aid for Scientific Research. (K. Kaziro).

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1. Native oxyhemoglobin of horse posesses one SH group freely reacting by the ferricyanide method.
2. An increase in the number of SH groups in the molecule of methemoglobin could be proved by the addition of benzoate in certain concentrations.
3. Maximum increase of SH groups were found to be three in number at the concentration of benzoate above 0.9M.
4. The concentration range of benzoate yielding either the increase of SH groups and the formation of hemichrome structure coincided fairly well with each other.
The author wishes to express his thanks to Prof. K. Kazir o, Dr. G. Kikuchi, Dr. R. Shukuya and Dr. K. Tsushima for the valuable advice, criticism and encouragement which they have given during the course of this work. Thanks are also due to the Scientific Research Fund of the Ministry of Education for grant.

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