Physiological roles of myo-inositol, which had not yet been elucidated, was investigated by using inositol requiring strains of yeast. The results of fundamental investigation are described in this paper. Yeasts were classified into five types according to the level of inositol requirement. Some strains accumulated a fairly large amount of inositol in the medium. These inositol producing strains include certain film-forming yeasts. At least two types of inositol exacting yeasts existed, those which died due to inositol deficiency and those which did not die. Cell death was presumed to be due to unbalanced growth, because death was not observed under condition where the biosynthesis of protein or nucleic acid was inhibited.
A method was developed to enrich auxotrophic mutants using Saccharomyces cerevisiae inositol-less mutant A-21-20 at the parental strain.

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Chicken feather keratin was solubilized by 0.1N sodium hydroxide heating at 90°C for 15min. A half of the starting keratin was recovered in a water soluble protein fraction but another half was dialyzed out as free amino acids. Many of these amino acids showed a different behavior on the column chromatography compared with the standards. Polypeptide production was not observed during the solubilization process of feather keratin by alkali. Solubilized feather keratin had an amino acid composition widely different from the ordinary feather keratin, rich in methionine, lysine and glutamic acid and poor in threonine, serine, cystine and arginine. Among the several methods tried to solubilize feather keratin, sodium hydroxide was the most drastic one in hydrolyzing the molecule.

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A new method for preparing NMN (nicotinamide mononucleotide) by the use of yeast 5'-nucleotidase is presented. After hydrolysis of NAD into NMN, adenosine and P_i by yeast 5'-nucleotidase which is a single protein having nucleotide pyrophosphatase activity, NMN in the hydrolysate of NAD was purified on active carbon and subsequently on Amberlite IRC-50.
In the typical experiment, 0.74g of NMN (88% purity) was obtained from 2 g of NAD preparation, giving 76% recovery on the basis of the theoretical value.
The NMN preparation was identified as NMN by IR spectra, UV spectra, paper chromatography, and also by component analysis.

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(-)-Menthyl carbinol (1-(R)-Methly-3-(R)-hydroxymethyl-4-(S)-isopropylcyclohexane) (4) was prepared stereospecifically in good yield by treatment of formaldehyde with the Grignard reagent from (-)-menthyl chloride (2), which was prepared from (-)-menthol-(1-(R)-methyl-3-(R)-hydroxy-4-(S)-isopropylcyclohexane) (1) by chorination using the Lucas reagent (HCl+ZnCl₂). The configuration of 4 was assigned by the chemical method.

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A stoichiometric analysis was carried out on the consumption of substrates and oxygen during the bacterial growth on gaseous hydrocarbons, based on the increase of cell mass and the pressure drop in a closed culture system which were measured by using a specially designed shaker flask. A bacterium capable of growing in the expense of n-pentane as the sole source of carbon and energy was employed, and an average yield factor as high as 0.84 was obtained throughout the experiment. As a result, the following stoichiometric equation was proposed for the formation of bacterial cells from n-pentane.
C₅H₁₂+4.26O₂+0.38NO₃=0.61C_4.17H_7.50O_1.55N_0.62+2.50CO₂+3.76H₂O

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The conformational changes of the alkaline proteinase of Aspergillus sojae were analyzed, after the treatments with urea and guanidine hydrochloride, by the optical rotatory dispersion, Cotton effects, ultraviolet difference spectra, and viscosity measurements. The results are as follows; (1) The treatment with 8M urea (pH 7.0) seemed to cause at least two different conformational changes assumed from the changes in the Moffitt parameter, a₀. One is a rapid and reversible change and the other is a gradual and irreversible change. During the process of the later change, it was observed that the complete disruption of the α-helices assumed from the b₀ value and the Cotton trough at 233mμ proceeded in parallel with the loss of enzymatic activity. (2) The conformational change after the treatment with 1.6M guanidine hydrochloride (pH 7.0) was considered to be rather small, judging from the changes in the a₀ value and intrinsic viscosity.
However, by this treatment, the two tryptophan residues which are buried in the interior of the molecule were exposed to the solvent, the α-helices were completely disrupted, and the enzymatic activity was completely lost.

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When the protease inhibitor from Penicillium cyclopium was mixed with the acid protease of the mold at acid pH formed a precipitate consisting of a enzyme-inhibitor complex. The precipitation occurred maximally at pH 3.0 and was interfered with by increasing amounts of salts and other protein. Subsequent incubation of the complex brought about inactivation of the enzyme and the inactivation was found to be accompanied by modification of the enzyme so that less was precipitable with trichloroacetic acid. Paper chromatography revealed that the enzyme on complete inactivation had been degraded to several fragments or polypeptides. The inhibitor acted on the enzyme in a catalytic fashion, bringing about degradation of more than a stoichiometric amount of enzyme. The proposed mechanism of the inhibitor action involved acceleration of auto-digestion of the enzyme which splits the molecule into small fragments and abolishes the activity.

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An improved method has been described for the isolation and purification of γ globulin from rice embryo. The method involves the extraction with phosphate buffer, pH 7.0 and ionic strength 0.1, the fractionation in saline solution of ionic strength 0.31, the removal of nucleic acids by precipitation with ammonium sulfate and the gel filtration chromatography on a Sephadex G-200 column. Although the preparations exhibited homogeneous patterns in sedimentation analysis, the electrophoretic patterns on polyacrylamide gels at pH 8.35 and ionic strength 0.11 exhibited at least two components. Three major components, γ1, γ2 and γ3 globulins, were isolated by ion exchange chromatography on a DEAE Sephadex A-50 column. These components were revealed to be homogeneous in electrophoresis as well as sedimentation. N-Terminal amino acid compositions have also been described.

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The molecular weight of γ₁ globulin was determined as 2.0 × 10⁵ by the Archibald method, and the intrinsic viscosity, [η], and the sedimentation coefficient, s°_{20, w}, were found to be 0.0424dl/g and 7.26S respectively. These values indicated the large asymmetry of the protein. The protein was composed of 18 residues of hexose, 3 residues of pentose, 6 residues of hexosamine and 1751 residues of amino acids: Lys₅₈, His₄₇, Arg₁₄₈, Asp₁₂₆, Glu₂₇₃, Gly₁₆₁, Ala₁₄₄, Val₁₂₁, Leu₁₀₆, Ile₇₂, Pro₈₃, Ser₁₃₆, Thr₄₈, Hyp₆₈, Cys₁₇, Met₁₆, Tyr₄₄, Trp₈, Phe₇₅ and amide ammonia₁₆₃. The N-terminal amino acid analysis suggested that the protein was composed of ten subunits. The properties and the composition were discussed in comparison with those of the 7S globulin of soybean cotyledon.

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Many phenoxypyridines were prepared and their herbicidal activities studied. Most 3- and 4-phenoxypyridines showed no remarkable herbicidal effects. Some 2-phenoxypyridines, however, exhibited high potentials as useful herbicides. 2-(4-Nitrophenoxy)-3, 5-dichloropyridine showed particularly promising herbicidal activity. On comparing the activity and structure of the 2-phenoxypyridines with those of the corresponding diphenylethers, the 2-pyridoxy group was nearly equivalent physiologically to the phenoxy group.

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The influence of the levels of dietary carbohydrate, protein, and fat on the capacity o1 glucose formation in liver slices and on the activities of gluconeogenic and glycolytic enzymes in the liver of rats were investigated. Incorporation of radioactivity from pyruvate-3-¹⁴C into glucose by liver slices not only increased in carbohydrate deficient groups, but also was affected by fat content of diets. PEPCK, FDPase, and G6Pase of rat liver were affected by the levels of dietary carbohydrate. Moreover, PEPCK and FDPase were increased by increasing the protein content of diets and G6Pase was increased by increasing the fat content of diets. The ratios PEPCK/PK and G6Pase/GK were increased significantly by decreasing the carbohydrate content of diets, but the ratio FDPase/PFK did not show any significant change among dietary groups. From these experiments, it was concluded that the capacity of glucose formation in the liver of rats was changed by carbohydrate and fat content of diets and changes in gluconeogenic capacity with diets were correlated with changes in G6Pase activity.

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Volatile carbonyl compounds produced in beef fat heated at 150°C in nitrogen were investigated. Ethanal, propanal, isobutanal, isopentanal, crotonal, benzaldehyde, acetone, methyl ethyl ketone, methyl isobutyl ketone, glyoxal, and pyruvaldehyde were isolated as their 2, 4-dinitrophenylhydrazones and identified by means of thin layer chromatography, infrared, mass and proton magnetic resonance spectroscopy. These carbonyls were considered to be contained also in the volatiles from beef fat heated in air from the results of thin layer chromatography.
Volatile carbonyl compounds of longer carbon chain produced in beef fat heated at 200°C in air were also examined, and hexanal, heptanal, 2-heptenal, octanal, 2-octenal, nonanal, 2-nonenal, 2-decenal, 2, 4-decadienal and 2-undecenal were tentatively identified by gas-liquid chromatography. The amount of long-chain carbonyls was larger and the oily odor in beef aroma was stronger in beef fat heated in air than in nitrogen.

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Genetic relatedness of 14 yeast strains and 2 mold strains was studied by the DNA-DNA hybridization method. The hybridization was performed between mitochondrial-DNA-free, ³²P-labeled DNA of Saccharomyces cerevisiae IAM 4009 and cold DNA of other strains. The DNA homology indices deviated considerably even among S. cerevisiae strains having similar GC contents, but, in general, yeast strains known to be able to mate with S. cerevisiae, showed high homology indices (35_??_70%). Other species of Saccharomycetaceae and 6 as-porogenous yeast strains exhibited values of 10_??_20%. The relatedness suggested from these results was confirmed by the competition experiments and also by the hybridization with ³²P-DNA of Candida pulcherrima IFO 0561. DNA's of Aspergillus oryzae I and Neurospora crassa IFO 6067 also exhibited low but appreciable homology indices (5_??_7%). These results were discussed from the aspects of phylogenetics and also of gene conservation in microorganisms.

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The stabilizing action of carboxymethyl cellulose (CMC-1 and CMC-2) on caseins was studied in the acidic pH region. CMC-1 stabilized 1% whole, α-, αS- and β-casein at pH 4.6 and 5.0, and at 5°C. But CMC-2 could not completely stabilize these caseins at pH 5.0. Interaction between k-casein and CMC-1 commenced when pH was adjusted to 6.3, but CMC-2 interacted with k-casein below pH 5.6. An αS- and k-casein mixture (4:1) with CMC-2 was destabilized by the addition of 0.02M NaCl or NaH₂PO₄ at pH 5.0. The αS/k ratio of the precipitated casein was about 10. But the same system with CMC-1 was not destabilized by the salts.

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Methyl α-ionylideneacetates were oxidized with selenium dioxide to a mixture of methyl 3'-keto-β-ionylideneacetates and a small amount of methyl 4'-keto-α-ionylidene-acetates followed by treatment with active manganese dioxide. By a similar oxidation methyl 3'-keto-β-ionylideneacetates were prepared from methyl β-ionylidene acetates. Methyl 4';-keto-α-ionylideneacetates were obtained by oxidation of methyl α-ionylideneacetates with tert-butyl chromate. Dehydrobromination of methyl bromoionylideneacetate, obtained by bromination of methyl 2-trans-α-ionylideneacetate with N-bromosuccinimide, gave a mixture of methyl 2-trans-dehydro-β-ionylideneacetate and methyl 2-cis-dehydro-β-ionylideneacetate. The growth inhibitory activities of these sesquiterpene carboxylic acids and keto esters on rice seedlings were tested.

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Some β-bisabolene derivatives, III, XX, XXVII and XXVIII, were synthesized and shown to possess the juvenile hormone activity.

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The structure of fragin, a new biologically active metabolite of Pseudomonas fragi, hasbeen determined to be N-(2-N-nitrosohydroxylamino-3-methylbutyl) octanamide (I). The presence of an unique N-nitrosohydroxylamino group was deduced from the physico-chemical evidences. The IR and NMR spectra together with the hydrolysis experiment suggested the presence of a sec, caprylamide group in the compound. The functions of the remaining five carbon atoms could be clarified on the basis of NMR spectra of the degradation pro ducts II, III and IV.

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Fragin (I) was synthesized as the racemate by use of isobutyryl chloride or isobutylaldehyde as a starting material.

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The structure of crystalline yeast phosphoglyceric acid mutase has been investigated by sedimentation-velocity and equilibrium measurements, optical rotatory dispersion measurements and viscometry. The data indicate that this enzyme is a. globular, compact and highly organized protein with a low helix content. The native structure remains unchanged at pH 10.5. Dissociation of the enzyme into subunits has been observed at pH values of 11.5 and above. From optical rotatory dispersion measurements, it is found that the enzyme loses a large part of its organized conformation when it dissociates in alkaline solution. On neutralization, the alkali-treated enzyme regains its activity. The ability to regain the enzyme activity is gradually lowered with the increase of pH value to be incubated and with time of exposure. Inactivation at pH 13.0 is almost irreversible. However, the reversibility of the inactivation at pH 13.0 is appreciably enhanced by the presence of phosphate compounds in the reactivation system. Particulary, it is found that presence of substrates or the coenzyme is effective for considerable improvement of the reversibility. Molecular weight analyses by ultracentrifugation indicate that subunits have approximately equal molecular weights and that the native enzyme is consisted of four polypeptide chains.

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