A gas-liquid chromatographic method using flame for determining was developed for determining the residues of benthiocarb in soils. Benthiocarb in soils was removed by steam-distillation, followed by liquid chromatography on active charcoal. The lower limit for detection of pure material was 0.002μg and that residues in soil was 0.02ppm. Recoveries for three soils ranged from 70.5 to 93.1% (average), when treated with three level of 0.32, 3.18 and 31.8ppm. Recoveries at the level of 0.32ppm were observed to be low.

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Oxalacetate carboxylyase was extracted from pig heart muscle and purified about 40 fold by means of acid and heat treatments, salting out and three steps of column chromatography. Some properties of the enzyme were studied by manometric and spectrophotometric measurements. The enzyme activity was optimal at pH 7. Km for oxalacetate was 4.3×10^-3M/liter and the activation energy of the enzyme reaction was 15 kcal/M. The enzyme was activated by certain bivalent cations, among which Mn²⁺ was the most effective. Cu²⁺, Hg²⁺, some metal chelating reagents (EDTA, citrate and Oxalate) and pCMB strongly inhibited the enzyme activity. Inhibition by avidin was not observed, suggesting that biotin was not involved in the reaction as the prosthetic group of the enzyme.

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The existence of oxalacetate carboxylase (OAC-lyase), distinct from other oxalacetate decarboxylating enzymes, was concluded by the following facts: (1) the enzyme action was not effected by ATP, ADP, acetyl CoA and avidin and was not stimulated by LTP, different from pyruvate carboxylase and phosphoenol pyruvate carboxykinase; (2) although an appreciable amount of malic enzyme activity was found in the crude extract of pig heart muscle, the purified preparation of OAC-lyase was completely free from this activity; (3) OAC-lyase activity was unaffected by NADP⁺ and L-cysteine, different from the decarboxylating activity of malic enzyme.
The reversibility of OAC-lyase reaction was studied by a tracer technique, and it was found that the reaction was practically irreversible.
As regards the physiological significance of OAC-lyase, a preliminary experiment on the transcarboxylation between oxalacetate and acetyl CoA by OAC-lyase were unsuccessful.

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Phospholipase A activity was hardly detected in Escherichia coli K12 sonicate when solvent-extracted (free) ³²P-phosphatides were used as substrate. Phosphatides bound in membrane were, however, actively hydrolyzed to give the corresponding lysolipids by an endogenous enzyme. The results indicated the presence in E. coli membrane of a novel phospholipase which can be more precisely called as lipoprotein phospholipase A. Lysophospholipase was shown to be present in the cellular soluble fraction.
With free phosphatides as substrate, alcohols and some water-miscible solvents, as well as nonionic detergents, markedly stimulated phospholipase A activity of the membrane, possibly by enabling the substrate to hold physical state in someway simillar to that in the membrane. Possible role of this enzyme in membrane lipid metabolism is discussed.

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An ethanol utilizing yeast, strain E-6, was isolated from leaves of a radish (Raphanus satiaus). The taxonomic study of the organism showed it belongs to the genus Candida. When the organism was grown on ethanol, about 200mg/liter of oily drops was formed on the surface of the culture. They were suggested to be a mixture of higher fatty acids by gas-chromatographical analysis. The main component of the acids was isolated as methyl ester by thin-layer chromatography. The chemical structure was examined by means of infrared, nuclear magnetic resonance, mass, and elementary analyses. The oxidation products of the component with permanganate-periodate and with nitric acid were determined. It was proved that the said main component was 15-hydroxy-9, 12-octadecadienoic acid.

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The milk-clotting activity of Mucor-rennin obtained from Mucor pusillus Lindt, was not changed by the addition of DFP in the reaction mixture. This finding suggested the probable absence of a serine residue at the active center of the enzyme. Sulfhydryl reagents such as Nekelgon, N-ethyl maleimide, PCMB failed to influence the milk-clotting reaction, indicating that a reactive sulfhydryl group is not required for the enzymatic activity. The activity was inhibited when Mucor-rennin was treated with iodine at pH higher than 5.0. It was shown that ¹³¹I₂ was incorporated into the enzyme. When Mucor-rennin was photooxidized in the presence of methylene blue, the milk-clotting activity was inactivated. In this case, tyrosine, tryptophan, and histidine residues in the enzyme were oxidized. Among these amino acids, the histidine residue was more rapidly oxidized than other amino acids. A parallel relation was observed between the decrease of the amount of histidine residue and the inactivation of the enzyme. From these results, it is concluded that the histidine residue present in Mucor-rennin has a relation to the active center of this enzyme.

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Bioassy procedure to evaluate biologically available energy of chemicals applicable to rats was established, and available energy of 36 chemicals was determined and compared with that estimated by chicks previously. Rats can utilize energy of propionic and butyric acids and n-hexyl propionate and butyrate well, while chicks cannot. Succinic acid, lauryl alcohol and dilauryl succinate at 5.00 dietary level were available by rats, though at 10% level lauryl alcohol was toxic. Ethyl lactate, octyl and decyl acetates and 1, 2-propanediol dilaurate were available by both rats and chicks. Availability of other 6 esters including ethyl succinate and citrate was low. Availability and digestibility of aldehydes by rats were also low.

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As the first step to reveal the size distribution of dispersing units in amylose, an amylose sample from corn starch was subjected to gel-filtration chromatography on columns of Sephadex G 200 and Sepharoses 6B, 4B and 2B under protection of the sample from retrogradation by the use of thiocyanate in the solvent system in the chromatography.
A considerable amount of dispersing units with unexpectedly large size was detected in the amylose sample as a fraction which was excluded from gels of Sepharoses, though the size distribution was considered to be rather continuous covering the units with smaller size of the regular amylose in the sample. The excluded fraction involved an appreciable amount of aggregates of amylose but no usual amylopectin. Nevertheless, the fraction in-volved some α-1, 6 glucosidic linkages susceptible to isoamylase. The digest of the fraction by the enzyme gave a product which showed size distribution similar to that of the regular size of amylose in the original sample. Both the digested product and the regular amylose had much larger size in molecular weight than the digest of amylopectin by the same enzyme.
The results indicate that the corn amylose sample is a mixture of the units with regular size amylose and those with very large one, the latter having various numbers of branches with the size of regular amylose. Thus, it is considered that the size of dispersing units in the corn amylose sample is characterized as a pattern of such continuous distribution ranging from few hundred thousand up to more than several million in terms of mole-cular weight.

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A growth factor (TJF) for a malo-lactic fermentation bacterium has been isolated from tomato juice, and found to be a β-glucoside. The NMR spectra of TJF and its acetate revealed that the glucosyl residue linked to the hydroxyl group at C-2' or C-4' of D- or L-pantothenic acid moiety. Then, 2'-O-(β-D-glucopyranosyl)-DL-pantothenic acid (I), 4'-O-(β-D-glucopyranosyl)-DL-pantothenic acid (II) and 4'-O-(β-D-glucopyranosyl)-D(R)-pantothenic acid (II-a) were synthesized, and II-a and 4'-O-(β-D-glucopyranosyl)-L-pantothenic acid (II-b) were obtained by the optical resolution of the acetate of II. Among the above compounds, II-a was identical with natural TJF regarding to the biological activity, NMR and ORD spectra, and thin-layer chromatography.

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The secondary structure of _γ1 globulin from rice embryo was investigated by means of optical rotatory dispersion, circular dichroism and infrared spectroscopy. The optical rotatory dispersion curve of the native _γ1 globulin gave a trough at 233mμ with a [m']₂₃₃ value of -2100°, and the Moffitt-Yang plot gave the parameters of a₀=-237 and b₀=-20. These data suggest the presence of 3% helix and 38% β structure in the molecule. Circular dichroism exhibits a negative extremum at 218mμ, giving a [θ]_R value of -3730, which suggests the presence of 16% β structure. Infrared spectrum of_??_thin film of _γ1 globulin showed absorption bands at 695 and 660cm^-1 with a small hump at 615cm^-1characteristic of the β structure, random coil and α helix, respectively. The protein in heavy water exhibits the absorption maximum at 1630cm^-1, which is also characteristic of the β structure.

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Thermostability of lightmeromyosin fraction 1 in 0.6m KCl was studied at pH7.0 and 65°C. The results observed in this study are as follows: (1) At the fixed condition, lightmeromyosin fraction 1 has been found to depolymerize into relatively low molecular weight proteins and peptides with length of incubation time. (2) A gradual decrease in helical content as well as intrinsic viscosity was also observed with thermal treatment. (3) Besides the slowly progressive changes in those physical parameters, a rapid loss in paracrystal forming ability of this highly helical subfragment of myosin at low ionic strengh occured in the early stages of denaturation.

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Penicillin-resistant mutants were derived from Corynebacterium hydrocarboclastus R-7. One of them produced 84g/liter of L-glutamic acid from hydrocarbon, though its parent strain produced 26g/liter.
The penicillin-resistant mutant had stronger activities of substrate consumption and oxygen absorption than the parent strain, and this was one of the reasons for the accumulation of a larger quantity of L-glutamic acid.
The interacellular content of phosphatidyl inositol mannoside (P.I.M) was related to the glutamate productivity, and the higher glutamate productivity of the penicillin-resistant mutant was supposed to be related to the remarkable diminution in the content of P.I.M.

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The biochemical mechanism of cold injury occurring in sweet potatoes stored at 0°C was studied. Oxygen uptake and RC ratio of mitochondria from sweet potatoes kept at 0°C for about 15 days declined when succinate or malate was used as substrate. As sweet potatoes suffered slight cold injury, a decrease in the respiratory rate of state 3 of mitochondria was observed. This decrease could be restored approximately to the level of that of healthy sweet potato mitochondria by the addition of cytochrome c when succinate was used as substrate. When sweet potatoes suffered severe damage, only partial recovery was observed with cytochrome c. While it was found that the respiratory rate in state 3 of mitochondria from chilled sweet potatoes was less inhibited by cyanide than that of healthy sweet potato mitochondria, the inhibition could be restored to that of healthy sweet potato mitochondria by the addition of cytochrome When malate was used as substrate, no effect of cytochrome c and NADH₂ was observed. There was no difference between chilled and healthy sweet potato mitochondria in enzyme activities of the electron transport system except for malate dehydrogenase.

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Some differences between linoleic acid hydroperoxides (LAHPO) and their secondary products in their function in cell damage were determined. E. coli cells were incubated with the autooxidized products of linoleic acid-1-¹⁴C; hydroperoxides and their secondary products. At O hr the secondary products showed a higher tendency to adhere to the cell surface, compared with LAHPO. The distribution of radioactivity in the precipitate and the soluble fractions showed that a major portion of the radioactivity incorporated was contained in the soluble fraction in the case of LAHPO, while in the case of the secondary products the radioactivity was contained mostly in the precipitate fraction. A positive relationship between a lowering of the inhibitory effect and u decrease in the incorporation was observed in the case of LAHPO when antioxidants were added to the reaction system. No such effect was observed with the secondary products.
These results may show that the inhibition of growth by LAHPO is due to a radicaltype reaction accompanied by the penetration of LAHPO into the cell sap, while the inhibi-tion of growth by the secondary products may be due to a different type of reaction which includes non-specific adsorption to the cell surface.

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Formation of protochlorophyllide and ribulose-l, 5-diphosphate carboxylase, both of which were constituents proper to chloroplast, was inhibited in the radish cotyledons grown with 4-thiouridine (0.5 mM), though the growth of the seedlings, activities of a cytoplasmic enzyme glucose-6-phosphate dehydrogenase and of a mitochondrial enzyme glutamate dehydrogenase in the cotyledones were not affected. Photo-induced formation of chlorophyll pigments and of chloroplastic ribosomal RNAs in the 4-thiouridine treated cotyledones were depressed as compared with controls. Interestingly, the effect of 4-thiouridine, however, disappeared with continuous illumination. Based upon these results, specific development of the chloroplast is discussed.

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_k-Caseins were prepared by the calcium-ethanol method, the Sephadex method and the urea-sulfuric acid method. Some important properties of _k-caseins were investigated using isoelectric focusing, starch gel electrophoresis, ultracentrifugation, chemical analysis, stabili-zation test of α_s-casein, and rennin treatment. Isoelectric focusing established that _k-casein had its isoelectric point near pH 6.0 in 6 M urea, usually accompanied by a second peak around pH 5.6. Ultracentrifugation, however, showed a single peak having a s_{20, w} value of 2.6_??_3.8 in the presence of 6 M urea and of 14.4 in the absence of such dispersing reagents. Normal contents of hexose, sialic acid, phosphorus, and nitrogen were about 1.5, 0.8, 0.2, and 14%, respectively. Relative patterns of amino acid composition were similar in all of the _k-caseins. In addition, amino acid composition in intact, _k-casein and in the further purified _k-casein which formed the second peak in DEAE cellulose chromatography were almost identical, indicating that the _k-casein of the first peak is not an impurity but is one of the components which formed the original _k-casein complexes. The ability of _k-caseins to stabilize α_s-casein in the presence of calcium increased when purified by DEAE cellulose chromatography.

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The phytohemagglutinin of the wax bean (Phaseolus vulgaris) could be resolved into an active and an inactive component when subjected to gel filtration on Sephadex G-100 in the presence of 8M urea and 0.001M EDTA, pH 5.5. Subsequent chromatography of the active component on Sephadex G-100 at pH 7.5 in the absence of urea revealed the presence of an inactive fraction (F-1-A) and a fraction (F-1-B) which had 350 of the activity of the original hemagglutinin. The activity of fraction F-1-A could be restored to that of the native hemagglutinin by treatment with cupric ions, whereas the activity of fraction F-1-B could be fully restored by treatment with either cupric or calcium ions.

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(1) Chitin-UDP acetylglucosaminyltransferase (E. C. 2. 4. 1. 16., chitin synthetase) in the cell-free system from phytopathogenic fungus Piricularia oryzae, and effects of various polyoxins and related compounds on the enzyme activity were studied. Polyoxins A_??_M, polyoxin A derivatives, polyoxin C derivatives, 5'-amino-5'-deoxyuridine, uridine and thy-midine inhibited equally the incorporation of N-acetylglucosamine (G1cNAc) from UDP-N-acetylglucosamine (UDP-G1cNAc) into chitin.
(2) Competition between the above inhibitors and UDP-G1cNAc was observed by kinetic studies. The Km for UDP-G1cNAc was determined to be 3.3×10^-3M and the Ki values for polyoxins A_??_M, except polyoxin C, were found to be in the range of 3.3×10^-5M to 3.4×10^-6M. For polyoxin C, 5'-amino-5'-deoxyuridine and uridine, the Ki values of 2.7×10^-3M, 8.0×10^-3M and 3.0×10^-3M were given, respectively. The inhibitor constants for other related compounds were also calculated.
(3) The values of binding affinity, -ΔG, for formation of substrate- or inhibitor-enzyme complexes were calculated from the Km or Ki values. In addition, partial binding affinities, -Δg, for certain moieties or groups of polyoxins were estimated from the -ΔG. For instance, the -ΔG values for UDP-GlcNAc and polyoxin L were 5.7 kcal/mole and 9.2 kcal/mole, respectively. And the -Δg values for the nucleoside moiety (part I^*), the car-bamylpolyoxamic acid moiety (part II^*) and the carboxyl group^* at C5' position of polyoxin L were 5.2, 3.5 and 0.7 kcal/mole, respectively.
(4) From the results obtained, the mechanism of action and relation between chemical structure and competitive inhibition of chitin synthetase were discussed.

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