Changes of ultracentrifugal patterns of soybean proteins by heating up to 100°C were almost completed at 80°C at lower ionic strength and at 90°C at higher ionic strength. How-ever, changes in DTNB reactive sulfhydryl groups, sulfite reducible disulfide bonds, ultraviolet difference spectra and turbidity of the protein solutions were still observed at temperatures higher than 80 or 90°C. These results suggest that 11S protein dissociates into subunits at a temperature below 80 or 90°C, and that the conformations of these subunits can change at a temperature above 80 or 90°C. When heated at high ionic strength, the protein solution became turbid because of aggregation of proteins. SDS polyacrylamide gel electrophoresis showed that aggregated proteins separated by centrifugation as precipitates were formed from low-mole-cular-weight subunits of 11S protein and non-aggregated proteins remaining in the super-natant were from 7S protein and high-molecular-weight subunits of 11S protein.

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Chymotrypsin and trypsin inhibitors were produced simultaneously in the culture broth of Streptomvices libani S-35. These inhibitors were purified and obtained as white amorphous powders. The properties of the chymotrypsin inhibitor were similar to those of known chymo-statins except that it was positive for Sakaguchi reaction. The presence of arginine residue was further confirmed by ¹³C-NMR study and, therefore, the inhibitor was presumed to be a new Sakaguchi-positive chymostatin in which the capreomycidine of chymostatin B was replaced by arginine. The properties of the trypsin inhibitor were the same as those of antipain. The Sakaguchi-positive chymostatin and the antipain were the same in amino acid sequence except that the former had phenylalaninal and the later had argininal at the C-terminal.

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Enzymatic properties of a galactolipase (G-2) which has the highest activity in four galacto-lipases of rice bran were investigated. The molecular weight was estimated to be about 4×10⁴ by gel filtration, and the Km value was 0.34mm for monogalactosyldiacylglycerol. The enzyme was activated markedly by sodium deoxycholate and slightly by calcium ion, but inhi-bited by EDTA, Triton-X-100, sodium dodecylsulfate, NaCl and organic solvents. The enzyme lost more than 95% of its original activity when heated at 50°C for 10min at pH 7.5. The enzyme catalyzed the hydrolysis of both galacto- and phospholipids. The relative hydrolysis rates decreased in the order of digalactosyldiacylglycerol>monogalactosylmono-acylglycerol>monogalactosyldiacylglycerol>lysophosphatidylcholine>phosphatidylcholine. The enzyme catalyzed the hydrolysis of fatty acid ester bonds at both C-1 and -2 positions of galactolipid. It is suggested that serine and cystine residues are important to the enzymic activity.

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Soybean seedlings were grown at 28°C in the dark or the light for 12 days, and four classes of sterol lipids, sterol esters (SE), free sterols (St), acylated steryl glycosides (ASG) and steryl glycosides (SG), were isolated from the cotyledons by solvent extractions, Florisil column chromatography, and thin-layer chromatography (TLC), successively. Each sterol lipid (SE, ASG and SG) obtained was hydrolyzed and then separately divided into sterol, fatty acid and/ or sugar fractions. The hydrolysates and St were analyzed mainly by gas-liquid chromato-graphy (GLC).
Under the two conditions tested, the main sterol lipid class was St during germination, the minor one being SG. With the progress of germination, St and ASG decreased under both conditions tested, whereas SE and SG increased, especially SE in the light-grown seedlings. The changing patterns of sterol and sugar compositions of ASG resembled those of SG, but those of fatty acid composition differed between SE and ASG. In general, the changes in fatty acid compositions of SE and ASG were more marked in the light-grown seedlings than in the dark-grown ones.

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Gamma-radiolysis of D-fructose in aqueous solution under an anaerobic condition was investigated in the presence or absence of radical scavengers. Radiolytic decomposition of fructose was considered to be mainly initiated by the hydrogen abstraction of hydroxyl radical to give fructose radical. One part of the radical was converted into deoxydicarbonyl sugars through its dehydration, and another part was transformed into dicarbonyl sugars by its dispro-portionation reaction. On the other hand, the addition of hydrated electron to fructose was proved by the irradiation with N₂O and KSCN, in which a slight amount of 1-deoxy-D-arabino-hexulose was identified as a product
Five deoxy and two dicarbonyl sugars were identified along with their G-values, and the radiolytic mechanism of D-fructose in the absence of oxygen was also proposed.

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β-Amylase producing microorganisms were effectively isolated by using an amylase inhibi-tor (S-AI). Among fortytwo strains isolated, strain No. 72 was found to be the most potent β-amylase producing microorganism, and was identified as Bacillus polymyxa. This strain pro-duced 45 units of β-amylase per ml in the medium consisting of 4% soluble starch, 1% meat extract, 1% peptone and 0.3% NaCl (pH 7.0) at 30°C. Two kinds of β-amylase, that is, 7.3mg of β-amylase I and 3.9mg of β-amylase II, were obtained from one liter of culture broth as electrophoretically homogeneous forms. β-Amylases I and II were very similar to each other in their enzymatic properties except the small difference in isoelectric point (I; pH 8.35, II; pH 8.59). β-Amylases I and II were most active at pH 7.5 at 45°C, and stable between pH 4 and 9 for 15 hr at 37°C. Both enzymes were strongly inhibited by PCMB, and reactivated by cysteine. The molecular weights of β-amylase I and II were estimated to be about 44, 000. The amino acid compositions were also studied.

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S-(β-Aminoethyl)-L-cysteine (SAEC), a sulfur analog of L-lysine, significantly inhibited the growth of wild-type strains of Candida species. The growth inhibition of C. pelliculosa de-pended on SAEC concentrations, but L-lysine and L-α-aminoadipate restored growth effectively. SAEC-resistant mutants were induced from the wild-type strain of C. pelliculosa by ultraviolet irradiation and N-methyl-N'-nitro-N-nitrosoguanidine treatment. Almost all resistant mutants excreted some L-lysine into the medium. Lysine excretion increased after repeated mutations. The mutant strain SR-V-1263 extracellularly produced about 2mg/ml of L-lysine after shaking culture for 96 hr. The effect of various factors on lysine accumulation was investigated with strain SR-V-1263. The concentration of extracellular lysine reached a maximum (3.2 mg/ml) in medium containing 2% polypeptone under the experimental conditions.

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When C₆-aldehydes (cis-3-hexenal, trans-2-hexenal and n-hexanal) were produced from C₁₈-unsaturated fatty acids by the chloroplast lamellae as an enzyme source, oxygen which may act in singlet state is required. Light illumination, CCCP and DCMU gave no effect on the enzyme activity, though the enzyme system was localized in chloroplasts. It was likely that galactolipids and/or phospholipids played an important role in exhibiting a stable and maximal enzyme activity because of the significant decrease in the activity after the treatment of tea chloroplasts with potato lipolytic acyl hydrolase. The activity of the enzyme system was also inhibited by DCIP, MB, PMS, NTB, SKF 525-A and cytochrome c. These results suggest that the enzyme system in chloroplasts is different from the lipoxygenase-hydroperoxide lyase system in etiolated seedlings and fruits.

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The effects of 2-ethylsulfonyl-7-methyl-5H-1, 3, 4-thiadiazolo [3, 2-α] pyrimidin-5-one on DNA, RNA and protein syntheses were investigated to elucidate the mode of cytotoxic action on Ehrlich ascites donor cells. By incubation of E-cells for 2 hr at a concentration of 40μg TPSO₂-2/ml, the biosyntheses of DNA, RNA and protein were inhibited 21, 69 and 57 percent, respectively. DNA-dependent RNA polymerase prepared from E-cells was inhibited 50% at a concentration of 15 μg/ml; DNA polymerase, protein synthesis system and thymidine kinase were scarcely inhibited. Therefore, TPSO₂-2 is postulated to act by inactivation of RNA polymerase or as an antagonist of nucleoside triphosphates, because it neither binds to DNA nor reacts with NTPs. However, TPSO₂-2 did not inhibit RNA polymerase from E. coll.

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2-Ethylsulfonyl-7-methyl-5H-1, 3, 4-thiadiazolo [3, 2-α] pyrimidin-5-one (TPSO₂-2) showed inhibitory activity on cellular respiration of Ehrlich ascites tumor cells (E-cells) and Escherichia coli at 3.9×10^-4M. In polarographic traces of rat liver mitochondrial respiration, the agent inhibited the energy transfer of oxidative phosphorylation at 8×10^-4 M. However, in the presence of tricine[N-tris(hydroxymethyl)methylglycine], the TPSO₂-2 inhibitory activity on cellular respiration disappeared. The permeability of cells was altered by TPSO₂-2 treatment, and this effect was interrupted by adding tricine. TPSO₂-2 did not inhibit the multiplication of E. coli in the presence of tricine but did inhibit E-cell multiplication. This means that the inhibitory activity of TPSO₂-2 on E. coli multiplication is attributable to respiration inhibition, whereas the cytotoxicity of TPSO₂-2 should be due to reasons other than respiration inhibition.

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A xanthine-oxidizing enzyme in a strain of Pseudomonas synxantha was purified and iso-lated as a crystalline preparation. The purification procedure involved ammonium sulfate fractionation, column chromatographies on DEAE-cellulose, DEAE-Sephadex A-50 and Sephadex G-200, and crystallization in the presence of ammonium sulfate.
The crystalline enzyme was homogeneous by the criteria of ultracentrifugation and poly-acrylamide get electrophoresis.
The enzyme was reddish brown and showed a characteristic absorption spectrum: it had absorption maxima at around 270 and 450 nm with shoulders at 385, 425, and 550nm. The enzyme was determined to have a molecular weight of about 540, 000, and to contain non-identical subunits with molecular weight of 76, 000 and 54, 000. The enzyme catalyzed the oxidation of hypoxanthine, xanthine, and some purine compounds, and NAD⁺ acted with it as an effective electron acceptor. The enzyme reaction was inhibited by some metal ions, such as Hg²⁺, Ag⁺, and Cu²⁺, and KCN.

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The structures of ten fatty acids, which were obtained by the hydrolysis of tunicamycin complex, were determined. GLC-mass, ¹H NMR and IR spectra showed that the major acids were trans-α, β-unsaturated iso acids with the formula C₁₄H₂₆O₂, C₁₅H₂₈O₂, C₁₈H₃₀O₂ and C₁₇H₃₂O₂. The minor acids were α, β-unsaturated normal acids and saturated normal and iso acids.

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Phosphatidylcholine (PC) was associated with soybean 7S globulin. The amount of bound PC depended on the amount of PC in an incubation mixture. Trinitrobenzenesulfonic acid (TNBS), 2-methoxy-5-nitrotropone (MNT), 2-hydroxy-5-nitrobenzylbromide (HNBB) and 8-anilino-1-naphthalene sulfonic acid (ANS) were used to investigate the reactivity of amino acid residues of PC-bound 7S globulin, and the interaction of PC with the modified 7S globulin was also studied with these reagents. It was found that PC was not bound to the specific amino acid residues in 7S globulin, while the fluorescence intensity of the ANS-modified 7S globulin associated with PC was decreased by increasing PC. This suggests that PC is bound to the hydrophobic region of 7S globulin.
PC affected the conformation of the protein and decreased the β-structure content by its binding to the protein.

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2-Phenylpropylguanidino-4, 6-dimethylpyrinudine (PPG-2) inhibited completely the respiration of Ehrlich ascites tumor cells (E-cells) at 3.5×10^-4M. Against Esherichia coli, the inhibitory effect was observed at 1.0×10^-4M; at a lower concentration, 3.3×10^-6M, the oxygen uptake was remarkably stimulated. In the polarographic studies of rat liver mitochondria oxidation PPG-2 stimulated the state 4 oxidation of succinate and released the inhibition by oligomycin. Therefore, it is supposed that PPG-2 acts like as an uncoupling agent. The ATPase activation by PPG-2, however, was not observed.

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Enzymatic synthesis of oligosaccharide through the transglucosylation reaction of bre-wer's yeast α-glucosidase was attempted in the reaction system containing only sucrose as sub-strate. As the transglucosylation product, a new nonreducing trisaccharide was chromato-graphically isolated in crystalline form (monohydrate), giving mp 139_??_142°C and [α]²²_D+120 (in water). The trisaccharide was confirmed to be 6F-α-D-glucosyl-sucrose, that is, O-α-D-glucopyranosyl-(1→6)-;O-β-D-fructofuranosyl-(2→1)-O-α-D-glucopyranoside, of which undeca-acetate gave mp 148°C and [α]²²_D+119° (in chloroform), and this sugar was named “isomelezitose.”

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Buckwheat α-glucosidase was modified with N-acetylimidazole in the presence of each of various maltooligosaccharides, and the protecting action of each saccharide was examined to determine the location of the modified subsites. For instance, the acetylation of the enzyme in the presence of maltotriose resulted in the negligible reduction of the affinities for maltose, malto-triose and -tetraose, but for longer maltooligosaccharides (G₅_??_G₇) to some extent. The results suggested that the tyrosyl residues acetylated were located in the regions of the subsite 3 and 5, which were further supported by the application of the subsite theory to the acetylated enzyme,

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Reduced and carboxymethylated adzuki bean proteinase inhibitors II and II were digested with trypsin and with staphylococcal protease. Chymotrypsin-modified and cyanogen bromide-modified inhibitors were also reduced and carboxymethylated. The amino acid sequences of the resulting peptides were determined by the Edman degradation procedure and the carboxypepti-dase technique. Inhibitor II was a single chain and consisted of 81 amino acid residues. Inhi-bitor 11' contained 72 amino acid residues and appeared to be derived from inhibitor II by loss of 9 amino-terminal residues. These adzuki bean inhibitors were found to be highly homologous to lima bean inhibitor IV.

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Pseudomonas M16 is the mutant derived from a facultative methylotroph, Pseudomonas N842, which is the potent producer of coenzyme Q₁₀ (CoQ₁₀). This mutant with elevated pro-ductivity of CoQ₁₀ was observed to accumulate the significant amount of another CoQ homolog, which could not be detected in the parent strain. This CoQ homolog was extracted from the intact cells of the mutant and purified to crystaline state. The chemical properties and the results of UV, NMR and mass spectrometries revealed that this CoQ homolog was CoQ₁₁.

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Experiments were carried out to examine the effects of the aging time on the rheological and chemical properties of milk casein dope solution. The results obtained were as follows:1) Viscosity and normal force of milk casein dope solution increased with the increase in aging time. 2) Viscosity and normal force of casein dope solution with added SDS increased rapidly with the aging time. 3) Amounts of lysinoalanine were increased with the aging time. Sodium chloride accelerated the produce of lysinoalanine, whereas cystein restrained it. 4) Although the viscosity and normal force of casein dope solution with added sodium chloride increased rapidly with the increase in aging time, those of casein dope solution with added cystein were low and did not change with the aging time. From these results, it was considered that the increase of viscosity and normal force in the casein dope solution with the increase in aging time might be due to the formation of lysinoalanine cross-links induced by a strong alkali.

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Experiments were carried out to examine the effects of aging time on rheological and chemical properties of soy protein dope solution. The results obtained were as follows: 1) Viscosity and normal force of soy protein dope solution decreased with the increase in aging time. 2) Electrophoretic patterns of the dope solution became obscure as the aging time increased, however, the sedimentation coefficients were constant and 2_??_3 S. 3) Amino acid analysis showed the remarkable decrease of cystin and the increase of cystein and lysino-alanine with the increase in aging time. 4) Viscosity of the dope solution with added mercapto-ethanol was low and did not change with the aging time. Moreover, the power law of 3.5 existed between the viscosity and the concentration of disulfide bonds. From these results, it was speculated that the decrease of viscosity and normal force in the soy protein dope solution with the increase in aging time might be caused mainly by the disruption of the intermolecular disulfide bonds due to the sulfhydryl-disulfide interchange reaction and the cleavage of C-S bonds to form lysinoalanine by alkaline hydrolysis.

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The distribution of choline oxidase activity was studied with cell-free extracts of yeasts, molds and actinomycetes. A fungus which was identified as Cylindrocarpon didymum M-1 showed the highest activity. The enzyme was purified from the cell-free extract of C. didymum M-1 by a procedure involving ammonium sulfate fractionation and DEAE-cellulose, hydroxyl-apatite and Sephadex G-150 column chromatographies. The enzyme preparation was homo-geneous when subjected to disc gel electrophoresis and ultracentrifugation. Sedimentation velocity yielded a value of s⁰_{20, w}=7.6 S. The enzyme showed a typical flavoprotein spectrum of absorption maxima at 276, 370 and 454 nm.

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Aiming to get useful steroidal alkaloids by tissue culture of Solanum laciniatum Ait., indefinitely growing callus tissue was prepared from the mother plant. Some nutritional requirements for the growth of the callus tissue were studied. By examining steroidal com-pounds in callus culture, cholesterol, stigmasterol, β-sitosterol, lanosterol, squalene, diosgenin and a new steroidal alkaloid were found to be formed in the callus culture. The new steroidal alkaloid was found to be solasodine derivative containing rhanmose and other unidentified sugars.

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The antioxidant effect of tocopherol was considerably increased by the concurrent use with a partially hydrolyzate of gelatin. Further, mixture of tocopherol, the gelatin hydrolyzate and organic acid exhibited a outstanding synergistic antioxidant effect on autoxidation of unsaturated fatty acid or lard.

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Leucomycin A¹ (LM A₁) was converted to leucomycin A₃ (LM A₃) by Streptomyces kitasatoensis is glucose-containing medium. On the other hand, butyrate, one of the pre-cursors of the aglycone, repressed the bioconversion of LM A_l to A₃. The role of butyrate has been examined in connection with that of glucose. It was found that the production of the enzyme which catalyzes the acetylation at C-3 of aglycone was induced by glucose, and that the induction was remarkably repressed by butyrate. Cerulenin, a specific inhibitor of fatty acid synthesis, was effectively employed for the bioconversion experiments.

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Cytosine-substituted phage T4 DNA (T4dC DNA) was demonstrated to be a splendid substrate for the assay of restriction endonucleases by agarose gel electrophoresis. For preparing those which cleave lambda phage DNA at few sites, T4dC DNA having appreciable number of cleavage sites was especially useful. As typical examples SaiI and XbaI restriction endonucleases were chosen and an advantage of T4dC DNA for the enzyme unit determination was described. Screening of new restriction endonucleases from Streptomyces strains was facilitated by using T4dC DNA as a substrate for the assay.

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A new, rapid and sensitive method for the quantitative determination of maridomycin (MDM) is proposed. The assay method is based on the reaction of the epoxy group of maridomycin with picric acid in ethyl acetate. This reaction product has absorption maxima at 415 and 475_??_480nm in alkali. The absorbance at 490nm, in a region where the inter-ference from picric acid is negligible, follows Beer's Law up to 1000μg of MDM per 1ml of sample solution. This reaction is not interfered with by the presence of other 16-membered macrolide antibiotics.

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