In connection with the preceding paper concerning the enhancement of radiation lethal effect by the NaCl treatment, the experimental evidences and the further discussion for the possible mechanism of the enhancement by the post-NaCl treatment are presented.
In order to elucidate the radiation damages of cell constituents and its enhancement by NaCl, the infrared analysis and isotopic experiments were carried out with cells of S. cereoisiae, Z. soya and E. coll.
Consequently, it has been concluded that the possible mechanism may involve the processes of increase in cell permeability by irradiation and of the denaturation of the critical cell constituents by increasing penetration of NaCl and thus the sensitivity of irradiated cells to NaCl may increase. The NaCl sensitive sites are considered not to be restricted to the biological targets for radiation inactivation by the supports of the survival curve analysis based on the target theory and of the isotopic experiment.

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An experimental procedure for preparing a homogeous mixture of cellulose and a small amount of concentrated sulfuric acid was introduced.
A diagram describing the proportions between soluble glucose-polymer, sulfuric acid and water in an equilibrium solution was constructed.
The degree of retardation of the hydrolysis of cellulose in a small amount of sulfuric acid was discussed as compared with the hydrolysis in the presence of an excess of acid.

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Since L-prolyl diketopiperazines, L-prolyl-L-valine anhydride and L-leucyl-L-proline anhydride, had been isolated from the culture filtrate of Streptomyces sp. S-580, the mechanism of L-prolyl diketopiperazine formation by Streptomyces has been studied. These two L-prolyl diketopiperazines were not formed from their constituent amino acids incubated with intact cell or cell free homogenate of this strain in buffered salt solution containing energy source. However, from milk casein, poly peptone or gelatin, the former two were components of the culture medium of this strain, hydrolyzed with the pure streptomyces-protease, these L-prolyl diketopiperazines were obtained (only from gelatin, glycyl-L-proline anhydride were obtained in addition to these two). Furthermore, in hydrolysis of some synthetic L-prolyl peptides with this enzyme, L-prolyl diketopiperazine formation were also studied, and as the result, glycyl-L-proline anhydride was obtained from glycyl-L-prolyl-L-leucine but no L-prolyl diketopiperazine was formed from L-prolyl-L-leucyl-glycine. From these evidences, the possible route of L-prolyl diketopiperazine formation by Streptomyces has been discussed.

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Some new allethronyl esters of cyclopropanecarboxylic acids were prepared, and their insecticidal activities were tested against common housefly. Allethronyl esters of cyclopropanecarboxylic acids having 3, 4-methylenedioxyphenyl group on the cyclopropane ring were more or less toxic. Among them, allethronyl 2, 2-dimethyl-3-(3', 4'-methylenedioxyphenyl)-cyclopropane-l-carboxylate was found to be more toxic than α-dl-trans-allethrin, and the calculated relative effectiveness were 1.48 and 1.21 on the mortality and knock-down activity respectively as compared with α-dl-trans-allethrin.

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The extracellular proteinase of Ps. myxogenes sp. is constitued with Ca as an essential component as shown in the previous paper¹⁾. This paper deals with a study concerning the step of incorporation of Ca in the synthesizing reaction of the proteinase of the bacteria.
A protein or peptide substance constituted from Ca is not found within the cells of the bacteria which have been shaken in the presence of a carbon source and Ca ion, while the proteinase is accumulated at the extracellular site. As it is sure that nitrogen material within the cells (which has been assumed to be a more complicated substance than amino acid, which is a precursor substance) contributes to the enzyme synthesis, the above result might suggest that Ca is not incorporated at the precursor state in the enzyme synthesis, or even if the incorporation really does occur at that state, the precursor substance is immediately secreted in the medium. However, we have not found the precursor material which is secreted in the medium where the material is activated auto-catalytically as seen in Streptococcal proteinase⁶⁾. Accordingly, it is difficult to consider the latter case to occur.
The total amount of organic nitrogen material secreted in the medium containing a carbon source by shaking the bacterial cells aerobically, is found to be identical in both the presence or absence of Ca ion, but the secreted protein content is remarkably diminished (to almost one-fifth) in the absence of Ca ion. Further, it is clear that the removal of Ca from the enzyme molecule, by treatment with EDTA at 50°C, results not only in inactivation of the enzymatic action but also exhibits the autosplitting phenomenon of the enzyme protein.
These results may lead to the assumption that Ca-free proteinase would be secreted in the medium regardless of the existence of Ca ion, and the enzyme is accumulated when it is stabilized by the constitution of Ca ion in the medium, whereas the auto-splitting phenomenon of the enzyme would take place in absence of the Ca ion.
Therefore, the incorporation of Ca in the proteinase synthesis by the bacteria is considered to occur in the completely synthesized Ca-free proteinase secreted in the medium.
The author wishes to express his sincere thanks to Prof. H. Katagiri of Kyoto University for his constant guidance and encouragement throughout this work. Thanks are also due to Mr. E. Masuo of this Laboratory for his assistance.

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1) Antiserum against the proteinase of Ps. myxogenes sp. was producted in rabbits by injection of the antigen proteinase.
2) By cross-absorption experiments, the crystalline proteinase used as the antigen was found to be of inhomogeneous nature even when it was recrystallized twice.
3) Inactivation of the enzyme by various treatments, such as heat, acid and EDTA, markably caused the same effect in decreasing its precipitin titer.
4) The proteolytic activity of the enzyme was found to be inhibited by its antibody.
5) The effect of the antiserum on various proteinases of other origins was studied. It was found that the antiserum inhibits the proteolytic activities of both strains of Ps. aeruginosa; while the proteinases of the other bacterial origins of different species and genus, and also those of mould and animal origins are never affected by the antiserum.
The author wishes to express his sincere thanks to Prof. H. Katagiri of Kyoto Univ. for his constant guidance and encouragement throughout this work. He is also indebted to Mr. S. Mayama of this Laboratory for his cooperation in carrying out this experiment. Thanks are also expressed to Dr. Nomoto of Scientific Research Institute, Dr. Yoshida of Noda Institute for Scientific Research, Nagase Ltd., Institute for Fermentation (Osaka) and Dept. of Science of Osaka Univ. for their kindly supplying various proteinase preparations and various different bacterial strains used here.

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β-(p-Chlorophenyl) mercaptocinnamic acid and β-(p-acetamidophenyl) mercaptocinnamic acid were synthesized and separated into cis- and trans-isomers of each. Their configurations were determined by ring closure to be thioflavons under mild conditions. trans-Acids have an absorption band at 8.3μ while cis-acids do not have such band. Other physical methods generally used to determine the geometrical configuration were of no avail for these compounds carrying a bulky group at β-position. cis-Acid was produced via isomerization from the trans-ester during the procedure of saponification.

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The single injection of levulinic acid oxime (250mg/rat) or α-ketoglutaric acid oxime (250mg/rat) on rats, carrying radioactive cesium, promoted both urinary and fecal excretion of this radionuclide. The administration of levulinic acid oxime (sodium salt) decreased the cesium retention by liver. The administration of the oxime did not have influence on the urinary excretion of sodium and potassium in normal rats. The toxicity of the oxime was low. The LD₅₀ of α-ketoglutaric acid oxime was 3500mg/kg (mice, intraperitoneally). (The LD₅₀ of levulinic acid oxime has already been indicated as 2040mg/kg (mice, intravenously)¹⁾.

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Besides P-factor¹⁾, Pediococcus soyae^{2), 3)} requires betaine (glycine-betaine) as a specific growth promotant. The maximal growth is obtained with the supplementation of both betaine and P-factor to the synthetic medium, while betaine only gives the half-maximal growth. When the organism is cultured in 18% salted media, the addition of both betaine and P-factor is essential for the occurrence of growth. Thus, betaine is requisite for Ped. soyae as a growth promoting factor and also as a factor bestowing the osmotelerant ability.

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(-)-Epicatechin was administered orally to rabbits and vanillic acid, 3-hydroxybenzoic acid, protocatechuic acid, and three kinds of neutral substances were found to be excreted in the urine. The three kinds of neutral substances were identified as 1-δ-(3-methoxy-4-hydroxyphenyl)-, 1-δ-(3-hydroxyphenyl)-, and 1-δ-(3, 4-dihydroxyphenyl)-γ-valerolactones, which are optical isomers of the three kinds of neutral substances excreted after administration of (+)-catechin. From the presence of these intermediate metabolites, it was verified that (-)-epicatechin is metabolized by the same mechanism as (+)-catechin described earlier.

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1) The current experiment was performed to clarify the progression of fibroin in the inside of the silkgland during growth of the fifth instar, by tracing radioactive fibroin which was made of C¹⁴ glycine.
2) The radioactive glycine, 0.5μc per larva, was given per os to silkworms, Si 122XNichi 122, in different periods from the beginning of the fifth instar to the end of the fifth instar. These worms were reared on mulberry leaves until they became matured larvae, one day before spinning. At intervals of 24 hours after the radioactive meal, the silkgland isolated from silkworm was used for making a radioautograph of the longitudinal section of the middle division.
3) Each fibroin synthesized by the posterior division at different period of the fifth instar moves in an ordered fashion as shown in Fig. 1, in the inside of the gland along the middle and the anterior division during growth of the silkworm.
4) Fibroin present in the middle division at the end of the fifth stage is due to the successive disposition, in the order synthesized, of each portion of fibroin synthesized at different periods of the fifth stage.

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All isomers of (±)-menthol were prepared. Particularly, (±)-menthol and (±)-isomenthol were obtained in a good yield from (±)-menthone and (±)-isomenthone respectively, by the treatment with sodium in aqueous ammonia, i.e., a novel method of reduction employed in this series. Besides, it was found that the substance, m. p. 121°, reported for (±)-menthyl 3, 5-dinitrobenzoate in the previous literature, is a mixed crystal of (±)-menthyl and (±)-isomen-thyl 3, 5-dinitrobenzoate.

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(+)-Menthone enol acetate was prepared from (-)-menthone. It was found that this compound can be reduced to menthols, 79% of (-)-menthol and 21% of (+)-isomenthol, through menthylacetate, or enolic menthone (menthone), by the treatment with sodium in aqueous ammonia, i.e., a novel method of reduction employed in this series.

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Determination of the I. T. T. (Indicator Time Test) value of beer has so far been conducted by the visual measurement. However, this visual judgement of the critical point, at which 80, o, of added dyestuff is accurately decolorized, is very difficult. We attempted to estimate the I. T. T. value more correctly using a spectrophotometer. On the basis of the following facts and observations, spectrophotometric determination of the I. T. T. value has been proposed. The absorption maximum of 2, 6-dichlorophenolindophenol was observed at 520 mμ, but the absorption of beer was hardly ever recognized at this wave length. Walpole's buffer solution was used for stabilizing the dyestuff at a pH similar to that of beer. Ethanol contained in beer did not affect the absorption of dyestuff. It was also found that the optical density of the dyestuff was proportional to the concentration both in water and in beer.

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The transfer of alkyl esters of sorbic, benzoic and salicylic acid from the medium to bakers' yeast cell was investigated, and both the quantity of the ester dissolved in the lipid phase of the cell and the quantity adsorbed on the solid phase were determined.
The dissolved quantity of these esters was very great in comparison with the adsorbed quantity. At the ester concentration which gives a definite inhibiting effect on the yeast growth, the adsorbed quantity remained constant, being independent of the kind of ester, while the dissolved quantity greatly varied according to the kind of ester. From this fact it was concluded that the toxic effect of these esters, as well as esters of p-hydroxybenzoic acid (cf. Part III), is exclusively limited by the adsorbed quantity.

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The adsorption of phenols such as phenol, o-cresol, thymol, o- and p-phenylphenol, guaiacol, eugenol, α- and β-naphthol on bakers' yeast cell was investigated in relation to their toxic effect on the yeast growth. It was found that a definite quantity of the adsorbed phenols is required in order to give a definite inhibiting effect, being independent of the kind of phenol, and it was concluded that the toxic effect depends upon the quantity of the adsorbed phenols.
The adsorbed quantity required to inhibit the yeast growth for two days was 14_??_19 m-mol./ kg-cell in all cases of the phenols examined, and this value is in fairly good agreement with that obtained in cases of acid antiseptics and their esters (cf. Parts II, III and IV). The inhibiting mechanism of these phenols was assumed to be the same as in cases of acid antiseptics and their esters.

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In this paper emphasis is placed on the utilization of fermentative production of L-glutamic acid in the pilot plant with formerly isolated Brevibacterium dicaricatum nov. sp. using 500-L and 50-KL fermenters.
It was found that the yield of L-glutamic acid was higher than 45% in each case on the base of consumed glucose when the hydrolysates of Cassava starch (Tapioka flour) was employed as sugar source.
The greatest advantage observed in this experiment was the remarkable reduction in time required for fermentation in comparison with the fermentation time necessary for the laboratory method. This is a very favourable factor for the industrial preparation of L-glutamic acid.

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