Candida utilis Ribose 5-phosphate ketol isomerase (EC 5. 3. 1. 6) was purified. The enzyme is homogeneous by ultracentrifugal analysis and disc electrophoresis. The isoelectric point of the enzyme is 3.8, Km for R 5-P is 0.108mM and Kis by 5'-AMP and 6-P-G are 0.16mM and 0.61mM, respectively. The thermodynamic parameters, ΔH, ΔG (35°C), ΔS (35°C) and E are 4336 cal/mole, -5629 cal/mole, 32.15 cal/deg•mole and 6360 cal/mole, respectively. The molecular weight of the enzyme is 183, 000 and the enzyme is assumed to consist of three subunits, one with a molecular weight of 75, 000 and two identical subunits each with a molecular weight of 54, 000.

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Inhibitory effects of 2-deoxy-D-glucose (2 dG) on methanol metabolism in Torulopsis A-12 were investigated. The remarkable inhibition was observed on growth in the presence of 50 μg/ml of 2 dG when methanol was used as a carbon source. At the earlier time of incubation with 2 dG, the incorporation of ¹⁴C-methanol into hexose-phosphate by intact cells was inhibited by 2 dG, and this led to the reduction of the intracellular concentration of hexosephosphates. In the later period of incubation the specific activity of alcohol oxidase reduced, and formate accumulated extracellularly.

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Hepta-O-acetyl-2-O-β-L-quinovopyranosyl-α-D-glucose (VI) and hepta-O-acetyl-2-O-α-L-quinovopyranosyl-β-D-glucose (VIII) were prepared by the coupling of 2, 3, 4-tri-O-acetyl-α-L-quinovopyranosyl bromide (IV) with 1, 3, 4, 6-tetra-O-acetyl-α-D-glucose (V) in the presence of mercuric cyanide and mercuric bromide in absolute acetonitrile.
Similarly, hepta-O-acetyl-2-O-α-L-quinovopyranosyl-α-D-galactose (X) and hepta-O-acetyl-2-O-β-L-quinovopyranosyl-α-D-galactose (XI) were prepared by the reaction of IV with 1, 3, 4, 6-tetra-O-acetyl-α-D-galactose (IX).
Removal of the protecting groups of VI, VIII, X and XI afforded the corresponding disaccharides. On treatment with hydrogen bromide, VI, VIII, X and XI gave the corresponding acetobromo derivatives.

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Phospholipase B from Streptomyces hiroshimensis was purified 220-fold in specific activity by means of acetone treatment, gel filtration on Sephadex G-75 and isoelectric focusing, and the recovery of the activity was 60%. The isoelectric point was found to be around pH 7.3 and the molecular weight was about 15, 000. The phospholipase B had an optimum pH of 9.0. The enzyme retained 80% of the activity when heated for 60min at 37°C. The activity was stimulated by Ca²⁺, Ba²⁺ and Triton X-100 and inhibited by Zn²⁺, Co²⁺, Fe³⁺, Al³⁺ Adekatol SO-120, sodium cholate, sodium deoxycholate, lauryl benzene sulfonate, Cation DT-205 and cetylpyridinium chloride. The enzyme attacked phosphatidylcholine more rapidly than phosphatidylethanolamine. Under the same condition, the enzyme also hydrolyzed the lysophospholipids, lysophosphatidylcholine and lysophosphatidylethanolamine.

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It has been confirmed that there are two kinds of sulfate groups in red-algae mucilage which form thermal reversible gel, one of which is axial with respect to the pyranose ring and the other equatorial. The former forms 3, 6-anhydro-L-galactose by desulfation and, at the same time, intermolecular interaction increases markedly due to hydrogen bonding, while in the latter this does not occur and, consequently, an increase in gelling ability is not observed.

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Hydrochloric acid treatment of methyl 3-(4-isobutylphenyl)-3-methylglycidate and methyl 2-hydroxy-3-(4-isobutylphenyl)-3-butenoate, a rearrangement product of the former, in acetic acid gave 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-isobutylphenyl)-propanal. The same treatment of 2-hydroxy-3-(4-isobutylphenyl)-3-butenoic acid gave 2-(4-isobutylphenyl)-propanal. Both 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-isobutylphenyl)-propanal were oxidized to 2-(4-isobutylphenyl)-propionic acid.

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The molecular weight of the yeast tannase [E. C. 3. 1. 1. 20, tannin acyl-hydrolase] of Candida sp. was determined to be 250, 000 by gel filtration on Sephadex G-200. The enzyme was dissociable into two identical subunits with molecular weight of 120, 000 on SDS-polyacrylamide gel electrophoresis. The amino acid analysis revealed that the enzyme consisted of 786 amino acid residues per protein molecule. The polypeptide moiety of the enzyme was 38% by the Lowry-Folin reaction and 35% by the amino acid analysis. The enzyme contained 62% neutral sugars, which were identified as mannose and galactose on cellulose thin-layer chromatogram and 2.2% hexosamines.

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The constituents of the neutral volatiles from air-cured Burley tobacco were studied using distillation, silicic acid column chromatography, preparative gas chromatography and GC-MS. The isolation and identification of 84 compounds are reported of which 27 are newly identified as tobacco constituents and 4 are new natural products.

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A species of rice bran lipase (lipase II) was purified by ammonium sulfate precipitation, followed by successive chromatographies on DEAE-cellulose, Sephadex G-75 and CM-Sephadex C-50. Both polyacrylamide disc electrophoresis and ultracentrifugation demonstrated that the enzyme protein is homogeneous. The isoelectric point of the enzyme was 9.10 by ampholine electrophoresis. The sedimentation coefficient of the enzyme was evaluated to be 2.60 S, and the molecular weight to be 33, 300 according to Archbald's method. The enzyme showed the optimum pH between 7.5 and 8.0, and the optimum temperature at about 27°C. It was stable over the pH range from 5 to 9.5 and below 30°C. In substrate specificity, the enzyme exhibited a high specificity toward triglycerides having short-carbon chain fatty acids, although it was capable of hydrolyzing the ester bonds in the rice and olive oil.

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A burnt flavoring compound, which imparts to aged sake its characteristic and dominant flavor, was isolated by Diaion HP-20, silicic acid and Dowex 1-X 8 (CH₃COO^-) column chromatography and chloroform extraction. Based on thin-layer and gas liquid chromatography, UV and GC-MS spectral data, it was identified as 3-hydroxy-4, 5-dimethyl-2 (5 H)-furanone and its structure was also confirmed by synthesis. It was suggested that this compound was formed by the condensation of α-ketobutyric acid with acetaldehyde which occurred from degradation of threonine.

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1) The addition of amino acids, such as threonine, homoserine and methionine, to producing cultures resulted in an increase of the production of Corynecin II. α-Ketobutyric acid showed the similar effect.
2) The incorporation of these amino acids and the ketoacid into the propionyl group of Corynecin II was confirmed by the feeding experiments with labeled compounds, whereas propionic acid-U-¹⁴C was incorporated poorly into Corynecins with a relatively high degree of randomization of radioactivities.
3) L-Valine-U-¹⁴C was incorporated into Corynecin III, suggesting that the isobutyryl group of Corynecin III was derived from L-valine vi α-ketoisovalerate.
4) The origin of the acetyl group of Corynecin I was discussed on the basis of the incorporation experiments with acetate, pyruvate and L-alanine, all labeled with ¹⁴C.

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Acid-soluble Folin-phenol reagent-positive material (FPM) released during autolysis of tissue slices from rats under various dietary conditions was studied. A marked release of FPM was observed during both aerobic and anaerobic incubations of liver slices from protein-depleted rats as well as during an anaerobic incubation of those from normal rats.
This marked release of FPM was proved, by analyzing acid-soluble fractions on Sephadex G-15 column chromatography, to be almost due to accumulation of xanthine and not to increased proteolysis.
The marked release of FPM under aerobiosis in diaphragm from normal rats was also almost due to accumulation of xanthine.

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Rennin action on κ-Casein was studied using the CM-cellulose method which determines the amount of para-κ-casein formed during the enzymatic hydrolysis of κ-casein. The reaction rate was measured as a function of the time and enzyme concentration. A Km value of 8.9×10^-4M and a V value of 1.2×10^-4M/min were obtained under the assay condition used in this study. The maximum initial rate of para-κ-casein formation occurred at pH 5.0 and 50°C. The present study also demonstrated that the CM-cellulose method is useful for measuring the rennin activity on κ-casein.

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A new polyacetylene was isolated from the roots of Solidago altissima L. by column and thin-layer chromatography. The structure of this polyacetylene was identified as methyl 10-(2-methyl-2-butenoyloxy)-cis-2, cis-8-decadiene-4, 6-diynoate from the results of its spectroscopic and chemical analyses.
This polyacetylene, as well as dehydromatricaria ester, inhibited the growth of the seedlings of barnyard millet (Panicum crus-galli L. var. frumeniaceum TRIN.).

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Xylan was isolated by alkaline extraction of the holocellulose from the stalk of Nicotiana tabacum, which was purified by DEAE-cellulose and ion-exchange resin column chromatography. Based on the results of methylation analysis, partial acid hydrolysis and enzymatic hydrolysis, the purified xylan was confirmed to be composed of a straight chain of β-(1-4)-linked D-xylopyranosyl residues. The degree of polymerization was determined as about 100 by membrane osmometry in water.

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In order to elucidate the biochemical mechanism of the alkaline protease accumulation from n-paraffins by a kabicidin-resistant mutant of Fusarium sp., the cell constituents and the extracellular products of the mutant strain were compared with those of the parent strain. No prominent differences in the cell constituents were observed between the parent and the mutant. From the analysis of the extracellular products, however the mutant was found to have a high productivity of some hydrolytic enzymes, such as amylase and ribonuclease, and ergosterol which is a structural constituent of fungal cell membrane. The relationship of secretion of ergosterol, resistance to kabicidin and accumulation of alkaline protease is discussed.

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It was shown that under alkaline conditions the cyclonucleoside 1 was converted to an imidazole cyclonucleoside 2, and under milder conditions it was converted to an amidine 3, which reacted with N, N'-thiocarbonyldiimidazole and cyanogen bromide as well as phosgene affording the corresponding ring closure products 8, 9 and 10.

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Nineteen out of 214 strains of microorganisms including moulds, bacteria, actinomycetes and yeasts, which were selected from the culture collection of our laboratory were found to produce the substances which flocculate Saccharomyces cerevisiae AJ 4005 (baker's yeast). Among them are Aspergillus sojae, Anixiella reticulata, Geotrichum candidum, Eupenicillium crustaceus, Circinella sydowi, Monascus anka, Sordaria fimicola, Pseudomonas fluorescens, Staphylococcus aureus, Corynebacterium brevicale, Brevibacterium insectiphilum, Streptomyces vinaceus.
The flocculants in the culture broth of these microorganisms precipitated readily by addition of acetone, and flocculated various microorganisms nonspecifically. The flocculant produced by Asp. sojae AJ 7002 sedimented activated sludge well.

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Effects of the precursors and intermediates of the NAD biosynthetic pathway, and of quinolinate analogues etc. on hog liver crystalline quinolinate phosphoribosyltransferase (an intermediary enzyme in the de novo NAD biosynthetic pathway) activity were investigated. The enzyme activity was inhibited by many kinds of nucleotides, phthalic acid and SH reagents. But amino acids, nicotinic acid and nicotinamide had practically no effect. The apparent inhibition by ATP removed by raising Mg²⁺ concentration. Phthalic acid was proved to be a competitive inhibitor to quinolinic acid. The Ki value for phthalic acid was calculated at 1.7×10^-4M by a Dixon plot.

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Several analogues of 3, 11-dimethyl-2-nonacosanone, one component of the sex pheromone of the German cockroach, were synthesized. Their activity for the male to raise his wings was assayed and summerized in Tables I and II.

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On the basis of chemical and physicochemical analyses, the structure 1-N-[2-O-(3-amino-3-deoxy-β-D-glucopyranosyl) cytosine has been assigned to hikizimycin, a new type of 4-aminoglycosylcytosine-antibiotic, isolated from the culture broth of a Streptomyces.

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dl-(1245/36)-4, 5, 6-Trichloro-1, 2, 3-trimethoxycyclohexane and dl-(1245/36)-2, 3, 4, 5, 6-penta-chloro-1-methylthiocyclohexane were synthesized from (1245/36)-3, 4, 5, 6-tetraehlorocyclo-hexane-1, 2-diol. dl-(1245/36)-1, 4, 5, 6-Tetrachloro-2-methoxy-3-methylthiocyclohexane and dl-(1245/36)-1, 4, 5, 6-tetrachloro-2, 3-dimethoxycyclohexane were synthesized from (12345/6)-1, 4, 5, 6-tetrachloro-2, 3-epoxycyclohexane. meso-(1245)-1, 2, 4, 5-Tetrachlorocyclohexane was synthesized from benzene via cyclohexadiene-1, 4.

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The 35/46-isomer^*2 of 1, 2, 3, 4, 5, 6-hexachlorocyclohexene isomerized to afford two new isomers, when heated in dimethyl sulfoxide. Their conformations were determined. The structures of related compounds were discussed.

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Pure (+)-trans-Verbenol (2b) and its antipode (2b') were synthesized for the first time and their optical purities were checked by NMR as their MTPA esters (2e and 2e', respectively).

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