The presence and the change of deoxy-ibosidic compounds with the incubation in the fraction extracted by acid from the chick embryo had been demonstrated with the aid of the organism, L. leichmannii.
(1) The main growth promoting deoxy-ribosyl compounds for the microorganism in the extract were identified as deoxycytidylic, thymidylic acids, thymidine, deoxycytidine and deoxyuridine by paper chromatography and paper electrophoresis.
(2) It was found that the content of free deoxyribosidic compounds which promoted the bacterial growth per 1 g of fresh embryo changed with the lapse of the incubated day, especially, the contents were minimum at the period from the 10th to 14_??_15th day in-cubation. At that period, the ratio of deoxy-ribotides attains to about 50% to total growth promoting compounds, but the ratio of deoxy-ribosides is lower than the other days.
(3) Of total growth promoting compounds for L. leichmannii, the change of ratio with the incubation of three pyrimidine deoxy-ribosides which played important roles in the synthesis of DNA was estimated. The in-creasing of deoxyriboside of cytosine was striking at 12_??_14th days incubation, that was the time of the most excellent growth of the embryo, whereas the change of deoxyuridine showed entirely opposite inclination.

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Ribose-5-phosphate ketol-isomerase, an enzyme isomerizing ribose-5-phosphate to ribulose-5-phosphate, is isolated from Candida utilis which is grown in a medium containing xylose. The enzyme is also purified by means of fractionation with ammonium sulfate, acetone, and by DEAE-cellulose column chromatography.
The enzyme has its optimum pH at 7.5 and optimum temperature at 50°C.
Michaelis-Menten constant for D-ribose-5-phosphate is 7.38×10^-4M and activation energy of the enzyme reaction is 10, 525 calories.
The enzyme activity is inhibited by p-CMB, EDTA and sodium pyrophosphate, and activated by the addition of magnesium ion.

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Extract of Candida utilis contains polyol: NAD oxidoreductase which catalyzes the conversion of polyols to the corresponding ketoses.
By fractionation with ammonium sulfate and on DEAE-cellulose column chromato-graphy, the purity of enzyme has been increased about 14-fold.
The relatively high activity with both xylitol and sorbitol suggests that they may be the natural substances for the enzyme.
Evidence suggests that this enzyme relates to the metabolism of D-xylose in Candida utilis.

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Some physico-chemical and enzymatic properties of four fractions of glucoamylase, isolated and purified from a culture of Aspergillus oryzae on rice, have been investigated in order to characterize and differentiate the components. Although four fractions were homo-geneous in sedimentation analysis, only two fractions were found to be homogeneous in electrophoresis. One of the components had a molecular weight of 69, 000 and an isoelectric point of 3.3. Four components resembled one another in their properties, except minute differences in their electrophoretic mobilities, sedimentation coefficients and pH-stabilities. These differences as well as those in the chromatographic behaviors suggest slight differences in the structures of the components. Nevertheless, the properties of these components, except the molecular dimension, were very similar to those of Taka-amylase B, which was isolated from Taka-diastase by Okazaki.

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As a fundamental approach to the problem of amino acid metabolism in soybean, changes in content of twenty-three free amino acids, two acidic peptides, ammonia, ethanolamine, urea and seventeen total amino acids of cotyledon, hypocotyl and root of soybean during germination were determined with an amino acid analyzer. Glycine Max M. var. T201 (non-nodule-forming) and Glycine Max M. var. T202 (nodule-forming) were used for this experiment. The content and composition of free and total amino acids of cotyledon in both T201 and T202 differ from those of other tissues in any stage of germination. How-ever, no significant difference between these two varieties of soybean has been recognized in patterns of free and total amino acids changes during germination.

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In dry bean and initial stage of germination a relatively large unknown peak appeared and disappeared thereafter when the change in free amino acid content during germination of soybean was analyzed with amino acid analyzer. From various tests on the unknown peak, it became obvious that the peak was consisted of two peptides, γ-glutamyl-tyrosine and γ-glutamylphenylalanine, which were discovered in soybean by Thompson et al. in 1962. The content of these peptides did not change during the first 20 hours of germina-tion, but they decreased rapidly thereafter and disappeared after 70 hours.

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The HM-phages contained only deoxyribonucleic acid (DNA) as the nucleic acid moiety. The DNA was extracted from the phages by the phenol method. The content of guanine plus cytosine (%G+C) in the DNA was determined by paper chromatography and by thermal denaturation method. The values of HM 2 (group I), HM 3 (group II) and HM 7 (group III) were 35, 30 and 29, respectively.
The DNA was also isolated from the two host strains of Clostridium saccharoper-butylacetonicum by the method of Marmur and by Saito and Miura's phenol extraction method. The %G+C of the DNA was 31. No unusual bases were detected in either the bacterial or phage DNA.

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The cow-liver, catalase was inhibited by 3-nitropropionate (3-NPA) at every pH tested. The 50% inhibition degree, ø, of 3-NPA under experimental condition was 8.7×10^-4M, which was almost that of phenol (1.0×10^-3M). Among 3-NPA, 1-nitropropane, and propionate, 3-NPA had the most effective inhibitory effect. The maximum absorption spectrum of free catalase in the Soret region was not shifted clearly by an addition of 3-NPA, but the intensity of it was decreased. The inhibition type of 3-NPA was riot definitely classified as the cyanide type. Results indicate that this inhibition essentially be due to reaction between the prosthetic group and anion form of nitro group in 3-NPA, and that the inhibitory action of nitro group may be stimulated by carboxylic group. Finally, this inhibition could be thought as a partial toxic cause in vivo.

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Inactivation of Bacillus subtilis' α-amylase by heat was found to be reversible under a certain condition, and the factors affecting there were investigated, distinguishing into two groups: those influencing on the inactivation process by heat and those on the reactivation at the subsequent incubation after heating. Generally, the amylase heated in borate buffer solution was best in the reactivation degree. For reactivation of the heat-inactivated enzyme there was found an optimum in temperature, pH and concentration of enzyme, respectively. The reactivation was temporarily prevented by urea, but irreversibly inhibited by either calcium salts or calcium binding agents. In the reversible heat-inactivation of the enzyme-was also found a reversible change in the absorption spectra as well as in the behavior of the enzyme toward proteinase.

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Treatment of mesityloxide with basic condensing agents resulted in formation of isoxylitones-A, B, C and D and isophorone. These compounds were purely isolated and assigned their structures from spectroscopic and chemical evidences. Isoxylitone-A and isoxylitone-B were conformers of 1-acetyl-2, 4, 6, 6-tetramethyl-1, 3-cyclohexadiene separat-ed by the rotational barrier of acetyl group and interconversional barrier of cyclohexadiene ring. Isoxylitone-C was 4-isopropenyl-1, 5, 5-trimethyl-1-cyclohexen-3-one. Isoxylitone-D was 5, 5-dimethy1-3-(1-isobutenyl)-2-cyclohexen-l-one.

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A thermophilic spore-forming strain HN-68, only D-xylose grown cells of which have an activity of D-glucose isomerization, was isolated from soil, and identified to be similar to Bacillus coagulans Hammer. The conditions necessary for maximal production of the glucose isomerizing activity by the cells from shaken cultures in D-xylose media were studied. Much higher activities were observed with the cells grown from 14_??_16 hours at 40°C on D-xylose medium containing yeast extract, ammonium chloride, manganese sulfate and calcium carbonate. D-Glucose isomerizing activity was also developed inductively by exposing the washed cells grown on D-glucose to D-xylose within one hour. With the use of living cells as an enzyme source, the addition of both cobaltous ion and toluene in reaction system remarkably enhanced the reaction rate of D-glucose isomerization.

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During the investigation on the metabolism of azelaic acid by Micrococcus sp., it was found that the bacterium produced a large amount of keto acid (α-ketoglutaric acid) under the restricted condition for nitrogen source. The acid was identified as α-ketoglutaric acid by physico-chernical and biological methods. The mechanism of the production of α-ketoglutaric acid from azelaic acid was investigated. From the result, it was suggested that α-ketoglutaric acid production proceeded through the further oxidation of acetic acid produced from azelaic acid and that the production might be functioned by TCA cycle enzymes of the bacterium. Similarly, α-ketoglutaric acid was found to be produced remarkably from other various fatty acids.

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The extracellular lipase from Candida paralipolytica required alkaline earth metal ion as the cofactor^*2 in the reaction mixture not emulsified but dispersed by shaking, con-tradicting the fact that it required bile salt or anionic surfactant as the essential activator^*3 in the systems emulsified with polyvinyl alcohol, as previously reported.¹⁾ The two kinds of factors necessary to activate both reaction systems respectively were unexchangeable for each other. These facts would be direct evidences of the difference of interfacial nature between two substrate forms prepared from the same substrate.
The zero-order reaction has been observed under the non-emulsified conditions and the activation mechanism by alkaline earth metal ions has been studied partly.

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The characteristics of the partially purified α-galactosidase from Streptomyces olivaceus and raffinose estimation method utilizing the en-zyme preparation were studied. (1) The enzyme exhibited optimum pH at 5.2 for raffinose and at 5.4 for melibiose. The enzyme was completely inactivated by mainaining it at 60°C for 15 minutes. The enzyme was found to be sensitive to sulfhydryl reagents. The presence of 2×10^-5_M p-chloro-mercuribenzoate, HgCl₂ and AgNO₃ caused complete inhibition of the enzyme activity. The enzyme indicated the transferase activity but it could hydrolyze raffinose quantita-tively into galactose and sucrose. It also hydrolyzed naturally occurring α-(1-6)-galac-. tosides. The order of the rate of hydrolysis was raffinose>stachyose>melibiose. (2) Raffinose estimation method was studied utilizing the enzyme preparation and 125_??_500μg of raffinose in the sample with or. without sucrose was estimated with an, accu racy of ±5%. Raffinose in the beet molasses was estimated by the utilization of the enzyme preparation and the mean value was found to be almost the same to that by paper chromatographic method. The enzyme mete has the advantage to be able to estimate raffinose in a short time with the simple operation as compared with the other methods.

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The structure-activity in α-alkylthio-cinnamyl penicillins was studied. These penicillins were prepared by condensing 6-aminopenicillanic acid with α-alkylthio-cinnamic acids. α-Methylthio-cinnamyl penicillin and its substituted analogues were highly inhibitory to Staphylococcus aureus 209P and some of them were also effective in vitro against benzyl-penicillin-resistant Staphylococci. trans-α-Methylthio-2-bromo-cinnamyl penicillin, which showed a good in vitro activity, was resistant to penicillinase and was stable in acidic aqueous solution.

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Relationship between serine dehydrase activity in rat liver and dietary protein and carbohydrate levels, using casein and wheat starch, was investigated. Between 10% to 50% of dietary protein levels the enzyme activity sharply increased with increase of protein level. The enzyme activity was also increased by the restriction of carbohydrate intake, even when protein intake was equal in amount. Apparently enzyme activity is controlled by dietary protein level and also by carbohydrate level. In the case of high protein or low carbohydrate diet these changes may be mainly acting for utilization of protein as caloric source.

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