1. Using a Co⁶⁰ gamma ray source (intensity 3×10³r per hours), the effects of irradiation on bovine serum albumin in dissolved or solid state were studied with amperometric titration of-SH groups, polarographic protein wave recording and paramagnetic resonance absorption spectroscopy.
2. The content of -SH groups was de-creased when a protein solution was irradiated, especially in the presence of air, while hardly any reduction was observed on the solid samples in the absence of air. Such a decrease of-SH groups would result from oxidation. Increase in the amount of-SH groups observed on the solid samples irradi-ated in the presence of air could be attribu-table to the secondary configurational changes of molecules.
3. Marked changes of polarographic patterns of protein double waves were observed on both dissolved and solid samples and their time course or correlation with dose of radiation was studied.
These changes in protein waves did not always run parallel with those in the content of titrable -SH groups.
4. Formation of free radicals in the protein molecules by gamma ray irradiation could be proved with ESR absorption studies.
The author wishes to express his cordial thanks to Prof. A. Inouye (Department of Physiology, Faculty of Medicine, Kyoto University) and Assistant Prof. T. Hashi (Department of Physics, Faculty of Science, Kyoto University) for their helpful advice and discussions. The author also wishes to express his appreciation to Dr. A. Hirai and Mr. K. Sugibuchi of Department of Physics for their valuable assistance in the ESR studies and to Mr. Y. Naka-yama (Institute for Chemical Research, Kyoto University) for his technical help in gamma ray irradiation.

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1. Catalase was photooxidized in the presence of methylene blue, resulting in a decrease in enzymatic activity and a destruction of amino acids. Following the kinetic analysis, the square of the remaining histidine residues was proportional to the remaining enzymatic activity during photooxidation. This indicates that two histidines are required for the enzymatic activity.
2. Absorption spectrum of catalase was changed by photooxidation and the absorbancy at 405mμ was prominently decreased as with cytochrome c, but not as with peroxi-dase. The rate of decrease in absorption at 405mμ and of inactivation of catalase during photooxidation were compared, and a close relationship was shown between these two rates.
The author wishes to express gratitude to Prof. Y. Oshima and Prof. M. Funatsu for their invaluable advice and criticism during this work.

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Assay methods for the estimation of sulfite reductase were devised with methylviolo-gen as an electron donor. Sulfite reductase in the extracts of Desulfovibrio was purified partially and its properties were investigated. Cytochrome c₃ was necessary in the reduction of sulfite with hydrogen, while other components besides the sulfite reductase was needed for the sulfite reduction when the cytochrome was employed as an intermediary electron carrier instead of methylviologen.
The authors thank Prof. S. Akabori and Prof. F. Egami for their valuable advices.

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Ester and amide of carbobenzoxy-L-glutamic acid-γ-hydrazide, a lysine analogous compounds, have been synthesized and tested their nature as substrate for trypsin. These compounds can be partly hydrolysed by the enzyme action. Optimum pH, K_m and proteolytic coefficient k₃ were also determined for the hydrolysis. Peptide and polymer containing L-glutamic acid-γ-hydrazide residues were also slowly hydrolysed by the action of the enzyme, but those containing D-isomer were not. The inhibition of the tryptic activity npon usual substrate by glutamic acid-γ-hydrazide compounds were studied.
The author wishes to express his hearty thanks to Prof. S. Akabori and Dr. A. Tsugita of our University, for their interest and encouragement throughout the course of this work.

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1. The acid-soluble fraction from tissues of rats injected with P³² were treated with Dowex 1 formate and the unadsorbable fraction was further analysed by the column chromatography with Dowex 50.
2. Radioactive o-phosphoryl ethanolamine and o-phosphoryl choline were isolated and identified on the Dowex 50 chromatogram.
3. CDP-ethanolamine and CDP-choline showing practically no radioactivity were also isolated and identified on the Dowex 50 chromatogram.
4. Phosphocreatine in muscle extract was identified on the Dowex 1 formate chromatogram.
5. Both column- and paper-chromato-graphic method for the separation of nitrogen-containing phosphoric esters were described.
The author expresses heartful thanks to Prof. N. Shimazono for his kind advice and encouragement.

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1. The inhibitory effect of light on the respiratory oxygen-uptake of a non-sulfur purple bacterium, Rhodoseudomonas palustris was investigated.
2. The exygen-uptake of intact cells in the presence of various substrates was found to be suppressed by illumination.
3. The cell-free extract of the bacterium retains the capacity to oxidize the acids of tricarboxylic acid cycle. An inhibitory effect of light on the oxygen-uptake was also observed with this fraction.
4. The cell-free extract was fractionated into chromatophore and colored supernatant fractions, and the latter into small particles and colorless supernatant. It was found that the first three (colored) fractions possess the capacity for oxidation of the above-mentioned substrates, while the colorless fraction was essentially inactive. Light inhibition of the oxygen-uptake was observed with all these colored fractions.
5. Light has no effect on the rate of anaerobic dehydrogenation of succinate and lactate with 2, 6-dichlorophenol indophenol as hydrogen acceptor.
6. The effect of various inhibitors and heat treatment on the rate of succinate oxidation in dark and light was investigated.
The author wishes to express his gratitude to Prof. H. Tamiya and Prof. A. Takamiya for their valuable advices and interests throughout this work. Thanks are also due to Dr. S. Morita for his discussion in this work.

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1. Isokinetin, 2-(N-furfuryl)-aminopurine, was synthesised and its effect of promoting growth of leaves was compared with that of kinetin, using Raphanus and Brassica as materials.
2. Isokinetin stimulates the growth of leaf, the activity being however, about 80 per cent of that of kinetin.
3. Both kinetin and isokinetin inhibit the growth of roots of Raphanus sativa and Brassica juncea.
4. Emphasis was laid on the fact that the mode of action of kinetin and isokinetin is profoundly different from those of gibberelline and indole acetic acid which are known to have no activity of stimulating growth of leaves and inhibiting growth of of roots.
The authors wish to express their hearty thanks to Prof. M. Kuru, School of medicine, Osaka University and Prof. R. Kinoshita, City of Hope Medical Institute, Duarte, California, U.S.A., for their interests in this work and encouragements throughout this research. They are also very grateful for a grant from the ministry of Education.

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In the early phase of phosphorus incorporation, a labile phosphorus compound showing active phosphorus turnover appeared in protein fraction obtained by the Schneider's procedure. In later phase, however, this labile compound was shown to be absent.

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1. Labelled glutamic acid was produced from acetate-1-and -2-C¹⁴ in the presence of NH₄Cl and phosphate salt by washed cell sus-pension of Brevibacterium flavum, No. 2247. The relative specific activities of glutamate to the substrate acetate were 1.63 and 2.88, respectively. The percentages of radioactivity in the carbon-1 were 41 and 14.6 per cent, and those in the carbon-5 were 57 and 2.1 per cent respectively.
2. From these results the main pathway of glutamate formation from acetate used as the sole carbon source in the intact cells was discussed and the isotopic data could be explained by the previously postulated pathway, under some conditions.
The authors are indebted to Prof. F. Egami and Dr. T. Yamada of the University of Tokyo, and Dr. H. Oeda and Mr. S. Motozaki of our laboratory for the helpful discussion and encouragement during the course of this work.

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1. When the glucose grown, resting cells of Brevibacterium flavum were incubated with acetate-2-C¹⁴ for various periods of time, C¹⁴ from acetate rapidly appeared in citrate, α-ketoglutarate, succinate, malate, glutamate, and aspartate as revealed by the two-dimen-sional chromatography and radioautography of the ethanol-soluble fractions obtained .from each sample of the suspension.
2. A method for kinetic analysis of the incorporation of labelled atom of a substrate into the metabolites was described in order to determine the metabolic pathway in vivo. When the percentage distribution of C¹⁴ among several particularly selected groups of the compounds was plotted against time, in order to determine the path of acetate metabolism, following reaction sequences were .obtained, in due consideration of the biochecal characteristics of the compounds concerned: acetate, malate, succinate, α-ketoglu-tarate, glutamate; malate, aspartate; succinate, citrate.
3. The present results indicate the operation of the modified TCA cycle with an additional “glyoxylate by-pass” in vivo, which has been postulated from the results in vitro for the glutamate formation from acetate.
The authors are indebted to Prof. F. Egami and Prof. B. Maruo of the University of Tokyo, and Dr. H. Oeda and Mr. S. Motozaki of our laboratory for the helpful discussion and encouragement during the course of this work. The authors wish also to thank Dr. T. Yamada of the University of Tokyo for the helpful advices and discussion on the kinetic analysis.

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1. A dehydrogenase was purified from Pseudomonas bacteria. This enzyme catalyzes the oxidation of glutaric semialdehyde in the presence of DPN.
2. The thiol group of the enzyme was shown to be essential for enzyme activity. The substrate specificity was found to be very high.
3. Glutaric acid was found to be the end product.
The authors wish to express their gratitude to Dr. M. Suda for his continuous support and advice in this work.

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It was found that Acetobacter sp. contains a coenzyme-independent aldehyde dehydrogenase beside a TPN-dependent one. The former was purified thirty-fold and its general properties were examined.
1. The enzyme reduced both uni- and di-electron acceptors such as ferricyanide, 2, 6-dichlorophenol-indophenol and methylene blue in the presence of acetaldehyde, but not TPN and DPN.
2. Its pH optimum was at pH 7.0 in citrate-phosphate buffer. It was fairly stable at pH 5.0 at a low temperature, but not at above 40°C.
3. Its substrate specificity was very broad, and it rapidly oxidized acetaldehyde, propionaldehyde, n-butylaldehyde and croton-aldehyde at almost the same rate. Its Km for acetaldehyde was 8.7×10^-5 moles/liter and for ferricyanide was 8.2×10^-4 moles/liter.
4. Its activity was strongly inhibited by p-chloromercuribenzoate, but it was little affected by hydroxylamine.
The reaction mechanism of the enzyme was discussed.
The author would like to express his sincere thanks to Prof. K. Okunuki, Department of Biology, Faculty of Science, University of Osaka, Osaka, for his valuable guidance during this study, and to Miss. A. Inoue for her technical assistance.

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Xanthurenic acid has been shown to be readily conjugated with sulfate in the presence of rat liver or kidney slices as well as the supernatant of liver homogenate. The position of the conjugation of the main product was concluded to be at 8 position of xanthurenic acid. This substance was found without adding any xanthurenic acid in the control experiment. In an in vivo experiment, xanthurenic acid was found to be conjugated very little with sulfate in the urine of rats dosed with XA, as already reported by Rotstein.
We wish to thank Prof, E. Boyland and Dr. P. Sims for their kind interest and for providing an authentic specimen of xanthurenic acid-8-methyl ether. The biliary fistula was prepared at the Chester Beatty Research Institute by Mr. G. S. Ramsay, F. R. C. S., and Miss M. Biggs, to whom we express our sincere thanks.
This investigation has been supported in part by grants to the C. B. R. I. from the Medical Research Council, the British Empire Cancer Campaign, the Jane Coffin Childs Memorial Fund for Medical Research, the Anna Fuller Fund, and the National Cancer Institute of the National Institutes of Health, U. S. Public Health Service.

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By using a substrate, polyoxyethylene sorbitan monolaurate, which is completely soluble in water, the inhibition of pancreatic lipase by various food colors was investigated kinetically.
Water-soluble azo dyes (Ponceau 3 R, Ponceau SX, Ponceau R, Orange 1 and Sunset Yellow FCF) and xanthene dyes (Erythrosine, Eosine and Phloxine) inhibited pancreatic lipase noncompetitively, while fat-soluble azo dyes (Orange SS, Yellow AB and Yellow OB) had no effect on pancreatic lipase. The two triphenylmethane dyes (Light Green SF yellowish and Fast Green FCF) had a slight effect on the lipase action noncompetitively, and Naphtol Yellow S and Indigo Carmine had no effect.
The author wishes to express his thanks to Prof. S. Shibuya, Faculty of Science of this University, and to Prof. H. Matsumura and Ass. Prof. S. Iguchi, Pharmaceutical Department of this University, for their kind guidance and valuable advice. The author is also indebted to Miss M. Hiraga for her helpful assistance.

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