Changes of disc electrophoretic and ultracentrifugal patterns of soybean protein by heating were different, depending on whether the protein is in soybean milk or in acid precipitated protein solution. It was revealed that ionic strength has definite effects on these changes, and this is why the changes are different between soybean milk and acid precipitated protein solution. 7S protein is sensitive to heating at higher ionic strengths, forming aggregates directly, whereas 11S protein is sensitive at lower ionic strengths, dissociating to subunits which form aggregates partly. The fact that 7S protein cannot form firm gel by glucono-delta-lactone after heating and 11S protein can form firm gel when reasonably heated is supposed to be attributed to the difference of the process of aggregates formation during heating between the two proteins.

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Effect of heavy metal ions on the growth and the iron-oxidizing activity of Thiobacillus ferrooxidans were investigated.
Cupric, zinc, cadmium, and chromium ions had no effect on the growth and the iron-oxidizing activity of cell suspensions or cell-free extracts of the bacterium in high concentrations (10^-3_??_10^-2M). Lead ion delayed the start of the growth slightly in 10^-3M, but it did not inhibit the iron-oxidizing activity of the cells in the concentration. Tin and molybdenum oxide ions inhibited both of them in the concentration above 10^-3M.
Mercuric mercurous, and silver ions had the most harmful effect. In the concentration of 10^-3M, each of the cations inhibited almost completely both the growth and the iron-oxidizing activity of the cells.
In the experiments with cell-free extracts it was observed that the activity of cytochrome oxidase (cytochrome a₅₉₇) operating in the iron-oxidizing system of the bacterium was specifically inhibited with mercuric ion in the concentration above 5×10^-4M.

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Establishment of a new method for preparation of xylobiose was investigated.
When hardwood xylan was hydrolyzed by the xylanase system of Streptomyces sp. E-86, the hydrolyzate mainly consisted of xylose and xylobiose in an approximate ratio of 1:1.
Yeast strains selected in this paper, effectively and selectively metabolized all of xylose without any degradation of xylobiose.
By successive treatments of xylan with Streptomyces xylanase system and xylose-metabolizable yeast, 70.4g of crystalline xylobiose was obtained from 172g of xylan.

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Myosin B from normal and PSE porcine muscles was studied by superprecipitation and SDS polyacrylamide gel electrophoresis. Similar studies were made on the fractions derived from the myosin B preparation after ultracentrifugation. Myosin B and its fractions from PSE muscle showed much less superprecipitation than normal. This difference between normal and PSE muscle seems to reflect differences in biological activity of their myofibrillar proteins, rather than differences in myofibrillar protein composition.

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The effect of various carbon sources on the formation of acetolactate synthetase (ALS) was investigated with Aerobacter aerogenes No. 19-35. ALS which has a pH optimum of 6.0 and is insensitive to end-product inhibition by valine, was found to subject to catabolite repression by glucose. The catabolite repression was dependent on phosphate deficiency. In contrast, in Aerobacter aerogenes I-12, isoleucine-less mutant, acetohydroxy acid synthetase (AHAS^r) which has a pH optinum of 8.0 and is insensitive to valine, was resistant to catabolite repression. Since both insensitive enzymes to valine inhibition was not subject to dual control. “Glucose-effect” of ALS was released by addition of orthophosphate and 6-mercaptopurine or by anaerobic culture. It was revealed that accumulation of valine was due to operation of the regulatory mechanism releasing catabolite repression of insensitive enzyme.
It was suggested that regulation of enzymes involved in valine biosynthetic pathway was closely concerned with glucose metabolism.

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The dissociation of wheat glutenin into subunits was observed by treatment with a small amount of mercuric chloride under moderate conditions, suggesting that the cleavage of inter-polypeptide chain disulfide bonds in the glutenin might occur. The dissociation into the subunits was examined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The electrophoretic patterns of the glutenin treated with mercuric chloride were essentially similar to those of the glutenin treated with 2-mercaptoethanol. Silver nitrate also had the same effects as mercuric chloride, and p-chloromercuribenzoate and N-ethylmaleimide showed no effect on the dissociation of the glutenin. Complete dissociation was achieved when the glutenin solution containing 0.5% SDS and 0.01M phosphate buffer (pH 7.0) was incubated with 10^-3M mercuric chloride (about four moles per mole of disulfide groups) at 30°C for 20 hr. Partial dissociation was also observed after 30min incubation. Increasing temperature and SDS concentration promoted the rate of the dissociation of the glutenin by mercuric chloride.

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Hesperetin-7-β-maltoside (V), -7-β-cellobioside (VI) and -7-β-lactoside (VII) were prepared by the coupling of hesperetin with the α-acetobromo derivatives of the appropriate disaccharides, followed by saponification. V was showed to be as sweet as glucose.
Naringenindihydrochalcone-4'-β-sophoroside (VIII), -4'-[β-D-glucosyl (1→2) β-D-galactoside] (IX) and also hesperetindihydrochalcone-4'-β-kojibioside (X), -4'-β-maltoside (XI), -4'-β-cellobioside (XII) and -4'-β-lactoside (XIII) were prepared by the catalytic reduction of the appropriate flavanone-7-β-glycosides in alkaline medium.
Their relative sweetness values were discussed in comparison with dihydrochalcones of naringin and neohesperidin.

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Cariogenic streptococci produce tenacious water-insoluble polysaccharides from sucrose and these form the structural intercellular matrix of dental plaque. Two Streptomyces species were isolated from soils on agar medium containing the water-insoluble polyglucan as a sole carbon source. They were identified as Streptomyces werraensis (strain F₁) and Streptomyces chartreusis (strain F₂). These strains produced extracellular enzymes which strongly solubilized the polyglucans from various strains of cariogenic streptococci. Strain F₂ produced polyglucanases under rather stationary cultural condition, while F₁ required vigorous aeration. The polyglucanases may provide a useful measure for the prevention and control of dental plaque formation,

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The nucleotides and the activities of both sucrose synthetase and granular starch synthetase in the konjak corm (Ainorphophallus konjac C. Koch) have been investigated as a preliminary experiment on konjak mannan biosynthesis. On chromatographic separation on anion exchange resin and paper of compounds present in the acid ethanol extract from the corms, ascorbic acid, AMP, ADP, ATP, ADP-glucose, UTP, UDP-glucose, GTP, and GDP-mannose were isolated and tentatively identified. An unidentified nucleotide was also isolated.
Of the three nucleotide sugars, UDP-glucose was the most plentiful, while ADP-glucose was the least. The sucrose synthetase in konjak corms was as active as that in other plants. These observations suggest that the mechanism involved in sucrose cleavage in konjak corms is the same as that in other plants, such as sweet potato roots. Starch synthetase bound to starch granules in konjak corms was also found to be active when ADP-glucose was used as glucose donor. But UDP-glucose could not be substituted for ADP-glucose.
Based on these observations the mechanism of konjak mannan biosynthesis is discussed.

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It was found in the previous paper¹⁾ that wheat gluten polypeptides gave higher molecular weights in SDS-PAGE^*2 than in sedimentation equilibrium. To clear the cause of the abnormality of gluten polypeptides in SDS-PAGE, behaviors of the SDS complex of gliadin IV were investigated in comparison with those of the standard proteins. The amount of bound SDS for reduced and alkylated gliadin IV was not different from the value obtained with usual proteins. In accordance with the results of Reynolds et al., ²⁾ the plot of log [η] against log M gave a slope of 1.1, supporting a rodlike structure of the complex. The intrinsic viscosity of the SDS complex of gliadin IV gave a higher value of 0.28 dl/g in comparison with the corresponding value of 0.15 dl/g for the standard proteins. The sedimentation constant was lower in gliadin IV (1.61 S) than in the standard (1.77 S). These facts indicate that the gliadin IV complex has a higher frictional coefficient for its molecular weight of protein, suggesting a more elongated structure than usual. The helix content of the complex of gliadin IV was extremely low (12%), It was suggested that the high proline content of gliadin gives an elongated structure to the SDS complex and this structure causes a low electrophoretic migration mobility and overestimation of molecular weight in SDS-PAGE.

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Screening was carried out to obtain microorganisms which produced the enzyme to reduce the disulfide bond, from our type cultures of yeast. Among many strains of yeast showing activity to reduce the disulfide bond, Candida claussenii, Candida brumptii and Candida rugosa were selected to have the highest activity. The enzyme activity was detected in the cell free extracts, but not in culture broth.
The highest enzyme formation occured during the exponential growth phase, and rapid decrease of activity was observed in the stationary phase. Pantothenate and boron ion contributed to enzyme formation, and biotin and zinc ion to growth. The maximum enzyme activity was obtained in the following synthetic medium: 10% sucrose, 0.3% (NH₄)₂SO₄, 0.5% KH₂PO₄, 0.15% MgCl₂•6HO₂ 0.05% CaCl₂, 0.015% MnCl₂, 0.001% pantothenate, 0.0001% biotin, 0.0001% H₃BO₃, 0.00004% FeCl₃•6H₂O and 0.00008% ZnCl₂. In addition, 30°C of the cultural temperature and vigorous aeration showed good results for enzyme formation.

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Thiol-disulfide interchange enzyme which catalyzes the thiol-disulfide interchange was purified from cell-free extracts of Candida claussenii by acid treatment, ammonium sulfate fractionation, aqueous polymer two phase method (Dextran-PEG system), CM-Sephadex column chromatography, Sephadex G-100 and Sephadex G-200 gel filtrations. More than four active fractions were obtained on CM-Sephadex column. Further purification steps from one of these fractions resulted in two purified enzyme preparations D-1-1 and D-2 of which the increase in specific activities was 8150- and 8450-folds respectively, over the crude extract. Both purified enzymes were homogeneous in ultracentrifugal analysis.

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The synthesis of a new series of N^α-benzyloxycarbonyl (Z)-amino acid and Z-dipeptide chloromethyl ketone derivatives is described. The new derivatives are as follows; Z-L-Leu-CH₂Cl, Z-L-Phe (NO₂)-CH₂Cl, Z-L-Tyr (Bzl)-CH₂Cl, Z-L-Tyr (Z)-CH₂Cl, Z-L-Tyr-CH₂Cl, Z-L-Glu (Me)-CH₂Cl, Z-L-Phe-L-Leu-CH₂Cl, Z-L-Tyr-L-Leu-CH₂Cl, Z-L-Leu-L-Phe-CH₂Cl, Z-L-Leu-L-Tyr-CH₂Cl, Z-L-Glu (Me)-L-Tyr-CH₂Cl, Z-L-Glu (Me)-L-Phe-CH₂Cl.

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2-(4-Isobutylphenyl)-propionic acid, which is known to have a high anti-inflammatory activity and has widely been used in the treatment of diseases caused by inflammation, such as rheumatism, was synthesized from methyl 3-methyl-3-(4-isobutylphenyl)-glycidate, via methyl 2-hydroxy-3-(4-isobutylphenyl)-3-butenoate (VI) in four steps.

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Absorption, translocation and metabolism of 2-tert-butyl-4-(2, 4-dichloro-5-isopropoxyphenyl)-Δ²-l, 3, 4-oxadiazolin-5-one (oxadiazon) in rice plants were investigated. Three types of ¹⁴C-labeled oxadiazon were used in this study. ¹⁴C-Labeled oxadiazon was applied to soil under submerged conditions and plants were taken for the preparations at various stages of growth and development. Oxadiazon was translocated remarkably to shoots and accumulated in the lower leaves and stems. A small portion of oxadiazon intaken in plants was translocated to head parts. Oxadiazon was chemically transformed in plants to produce dealkylated compounds, oxidized alcohol and carboxylic acid as metabolites. In addition, two unidentified metabolites were detected, one of which was translocated to head parts from leaves and stems. Translocation and accumulation of oxadiazon and its metabolites were discussed in relation to physiological conditions of rice plants.

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Out of metabolites of 2-tert-butyl-4-(2, 4-dichloro-5-isopropoxyphenyl)-Δ²-1, 3, 4-oxadiazolin-5-one (oxadiazon) in rice plants one of the unidentified compounds nominated as M-1 was found much in head parts as compared with the parent compound and other metabolites. Identification of M-1 was made by means of thin-layer chromatography, gas-liquid chromatography, mass spectrometry and coincidence by the synthetic compound.
M-1 was identified as 1-(2, 4-dichloro-5-isopropoxyphenyl)-1-methoxycarbonyl-2-trimethyl-acetyl-hydrazine and a pathway of cleavage of oxadiazolin ring of oxidiazon in rice plants was confirmed.

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Eighty-five strains of bacteria were screened for selection of microorganisms suitable for industrial production of polynucleotides. Among these bacteria, Achromobacter sp. KR 170-4 (ATCC 21942) was found to be rich in polynucleotide phosphorylase (PNPase) in its “salt-shockate” as compared with the other strains tested. PNPase was purified about 50-fold from the “salt-shockate” of Achromobacter sp. KR 170-4, and properties of the enzyme were elucidated. Optimal pH for reaction was 10.1. Stable pH range at 37°C was between pH 6.5 and 10.5. Optimal temperatures were 46°C for polymerization of ADP or IDP, and 43°C for CDP or UDP. The enzyme was stable below 55°C at pH 9.2. The enzyme required Mn²⁺ rather than Mg²⁺ unlike the other PNPases reported. Optimal concentration of Mn²⁺ was 6mM.

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The nature of the soluble proteins and peptides released from myofibrils by treatment with CASF (Ca²⁺-activated sarcoplasmic factor) was investigated by using polyacrylamide gel electrophoresis in both a nondenaturing and a denaturing (sodium dodecyl sulfate=SDS) solvent and by using gel permeation chromatography on Sepharose 6 B. Both CASF and trypsin treatment cause removal of Z-disks before causing other ultrastructurally detectable degradation of myofibrils. CASF treatment of myofibrils releases a protein that is identical to α-actinin, one of the known components of the Z-disk, on the basis of mobility in polyacrylamide gel electrophoresis in a nondenaturing solvent and in SDS and on the basis of elution from gel permeation columns. Trypsin treatment of myofibrils releases a number of smaller molecular weight products that cannot be identified with any of the known myofibrillar proteins. Hence, CASF seems to remove Z-disks from myofibrils by means of a very specific proteolytic activity that releases α-actinin without extensively degrading it. Trypsin, on the other hand, probably seems to remove Z-disks by degrading α-actinin to peptides.

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Formation of CDP-choline from CMP consists of two reactions; (1) phosphorylation of CMP to CTP catalized by CMP kinase system, (2) condensation of CTP and phosphorylcholine catalyzed by pyrophosphorylase. The formation of CDP-choline has been achieved only by dried cells of yeasts, but not by intact cells. However, in this paper it is revealed that intact cells of Saccharomyces carlsbergensis carried out the above two reactions upon treatment with some detergents: Triton X-100, Nonion B, Ampholytic Detergent A, Anion C. Among these detergents, Triton X-100 was the most effective for the formation of CDP-choline. From the effect of Triton X-100 on these two reactions, difference of localization of these two kinds of enzymes was discussed.

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Many 4-nitro diphenylether derivatives with R-S (O)_x-substituents were systematically synthesized and their pesticidal activities were investigated. 3-n-Propylthiophenyl 4-nitro-phenyl ether and its sulfoxide analog exhibited remarkable acaricidal and chlorosis-inducing activities on the young leaves of plants. For all compounds with the substituent at the 4 position in the 3-n-propylthio (and -sulfinyl) phenyl group, chlorosis-inducing activity vanished and an acaricidal activity stronger than that of the parent compound appeared. Evidence that the acaricidal and chlorosis-inducing activities are greatly influenced by the size of the 4-substituent and the hydrophobicity of R in the 3-R-S (O)_x-substituent is presented.

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Several methyl-substituted cyclopropanecarboxylates were prepared and their steric configurations were established. The insecticidal activity against the housefly of their 5-benzyl-3-furylmethyl esters were tested. Among the substituents on cyclopropane ring, cis-methyl group to ester linkage has been found to be the most essential part for toxicity and trans-methyl and trans-isobutenyl groups greatly enhance its toxic activity.

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The specificity of proteinase K from Tritirachium album Limber was determined using various synthetic peptide substrates. The esterase activity against N-acylated amino acid esters indicated that the enzyme is primarily specific against aromatic or hydrophobic amino acid residues at the carboxyl side of the splitting point. Secondary interaction for hydrolysis was also studied using peptide esters or others, which showed that the enzyme activity is markedly promoted by elongating the peptide chain to the N-terminal from the splitting point. Thus, peptide chloromethyl ketone derivatives such as Cbz-Ala-Gly-PheCH₂Cl inactivated the enzyme activity markedly.

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Quinolinate phosphoribosyltransferase (an intermediary enzyme in the de novo NAD biosynthetic pathway) was purified from hog liver and its crystallization from a mammal was successful for the first time. This crystalline enzyme preparation was certified to be homogeneous by ultracentrifugal analysis and polyacrylamide gel disc electrophoresis. Its molecular weight was 173, 000 using the gel filtration method, and 172, 000 using sedimentation velocity analysis. The subunit molecular weight was estimated at 33, 500 with SDS polyacrylamide gel disc electrophoresis. Several physico-chemical parameters were also determined.

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