This paper deals with yeast cell-wall lytic enzymes formed by Streptomyces with regard to the connection with the cell-wall structure.
In the first place, 29 organisms of β-glucanase-producing Streptomycetes were selected among 777 strains belonging to genus Streptomyces by means of a cylinder-plate method employing the yeast glucan as a substrate. As for these organisms, the depolymerizing activity against the yeast glucan was considered to be mainly due to β-1, 3-glucanase activity. Against the heat-treated cell of bakers' yeast, the crude enzymes merely showed poor lytic activities, however, in the combined employment with some protease prepara-tions, especially with an alkaline protease from St. satsumaensis nov. sp., a remarkable increase of the lytic activities was demonstrated. On the other hand, the intact cell wall of bakers' yeast, or both the heat-treated and the intact cells of Sacch. cerevisiae 18.29 strain were dissolved very easily by a sole action of β-glucanase or of protease, respectively. In consequence, it seemed that the lysis occurred with different mechanisms in response to differences of substrates. On this subject, the results of investigations and discussions were described in special measure. In addition, the possibility, that some other enzymes than β-glucanase or protease might concern to the lysis of the cell wall, was also investigated and discussed.

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Gelatin was extracted from limed calf skin after a 30 sec. heat treatment with an urea solution in yield of a 40%, whereas gelatin was obtained merely in yields of 30_??_35% by the widely adopted hot water extraction method. The urea-extracted gelatin showed higher jelly strength and melting point, but was lower in ash content and exhibited lower relative vircosity. Animal feeding tests revealed that the urea-extracted gelatin was quite similar to the hot water-extracted one regarding the nutritional qualities, and it contained no disagreeable or acute toxic factor which might be produced during the course of the extraction.

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The effect of seven synthetic synergists upon the knockdown speed of four pyrethroids against larvae of the common house mosquito, Culex pipiens pallens Coquillett was evaluated with the bioassay by means of petri dish method previously proposed by the author. The results indicated that six synergists studied, except MGK-F5026, decrease the knockdown speed of pyrethrin, allethrin, barthrin and dimethrin against mosquito larvae.

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During the course of the study on biotin vitamers production by a hydrocarbon-utilizing bacterium, strain 5-2 (Pseudomonas sp.), it was found that crude RNA-alkali-hydrolyzate from yeast increased the accumulaion of biotin vitamers, most of which was determined as desthiobion, and that adenine in the crude RNA-alkali-hydrolyzate was a potent stimulator. Effect of adenine on biotin vitamers accumulation was observed in the medium with either hydrocarbon or glucose as a sole carbon source. The accumulation of total biotin vitamers by some other bacteria was also increased by adenine but that of true biotin was scarcely increased or inhibited by adenine.
The role of adenine on the accumulation of biotin vitamers was investigated with non-proliferating cells of strain 5-2, and it was supposed that adenine would not only inhibit the accumulation of true biotin but, as a result, cause the large accumulation of biotin vitamers which might be intermediates of biotin synthesis. When the medium was supplemented with excess biotin, complete repression occurred even in the presence of adenine.

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Seventeen rethronyl esters were prepared and their toxicities towards the housefly were measured and compared with those of allethrin or standard pyrethrin. As a result, a new acid comporlent with a high activity, 2, 2, 3, 3-tetramethyl-cyclopropanecarboxylic acid, was discovered and some information was obtained about the correlation between chemical structure and activity.

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An alkaline proteinase of Aspergillus sydowi (Bainier et Sartory) Thom et Church has been purified approximately 4.5-fold from a culture filtrate by fractionation with ammonium sulfate, treatment with acrynol and Alumina gel C_γ, and DEAE-Sephadex column chromato-graphy. The purified proteinase obtained as needle crystals was monodisperse in both the ultracentrifuge and the electrophoresis on polyacrylamide gel.
The optimum pH and temperature for the activity were 8.0 and 40°C, respectively. Fifty per cent of the activity was lost at 45°C within ten minutes and 95% at 50°C. At 5°C, the enzyme was highly stable at the range of pH 6 to 9. None of metallic salts tested promoted the activity, but Zn⁺⁺, Ni⁺⁺ and Hg⁺⁺ were found to be inhibitory. Sulfhydryl reagent, reducing and oxidizing reagents tested except iodine had no effect on the activity, but potato inhibitor, DFP and NBS caused a marked inhibition.

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The alkaline proteinase from Aspergillus sydowi was markedly protected from inactivation by the presence of Ca⁺⁺ in the enzyme solution. The protective effect of Ca⁺⁺ was influenced remarkably by the pH values of the enzyme solution, i.e., optimum concentrations of Ca⁺⁺ for the protective effect at pH 7.1, 7.5 and 7.8 were 10^-2, 10^-3 and 10^-4M, respectively. Conversely, at higher pH values such as 9.0, Ca⁺⁺ accelerated the rate of inactivation. There was a parallelism between the loss in activity and the increase in ninhydrin-positive material in the enzyme solution.
The proteinase acted on various denaturated proteins, but not on native proteins. In digestion of casein by the proteinase, 92% of nitrogen was turned into soluble form in 0.2M trichloroacetic acid solution, with 14_??_17% of peptide bonds being hydrolyzed. Casein hydrolyzed with the Asp. sydowi proteinase was further hydrolyzed by Pen. chryso-genum, B. subtilis or St. griseus proteinases, which further increased the free amino residues in the reaction mixtures. On the contrary, the Asp. sydowi proteinase reacted only slight-ly on casein hydrolyzed by the above-mentioned proteinases.

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Streptamine (scyllo-inosadiamine-1, 3²⁾) was synthesized from conduritol-F³⁾ dibromide, via one of its diazido derivatives. At the same time, a new isomer of inosadiamine, rac-inosadiamine-1, 2, ²⁾ was also prepared. Its configuration was induced from the synthetic intermediates and its NMR spectrum.

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Some physicochemical properties and amino acid composition of alkaline proteinase from Aspergillus sojae were found to be as follows: The isoelectric point was at pH 5.1. The molecular weight was 25500 using the Sheraga-Mandelkern's formula, based upon the values of the sedimentation coefficient (s_??__{20, w}=2.82 S), the intrinsic viscosity ([η]=0.027 dl/g), and the partial specific volume (_??_=0.726ml/g). The enzyme contains 16.8% of nitrogen and is composed of 250 residues of amino acid; Asp₃₁, Glu₁₉, G1y₂₇, Ala₃₂, Val₁₈, Leu₁₄, Ile₁₄, Ser₂₈, Thr₁₈, (_??_)₁, Met₂, Pro₆, Phe₇, Tyr₈, Trp₂, His₅, Lys₁₄, Arg₃, (amide-NH₃)₂₀.

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Characterization of 5-dehydroquinate hydro-lyase extracted from bomboo shoot was carried out. The enzyme was active over a broad range of pH with no marked peak between pH 6.0 and 8.0. Michaelis constant (K_m) for dehydroquinic acid was found to be 1.3×10^-5_M at pH 7.4. The enzyme activity is highest in the top and tends to decrease quite gradually toward the lower parts of the bamboo shoot, and the results suggests a possible participation of the enzyme in the biosynthesis of lignin through shikimic acid pathway. 5-Dehydroquinate hydro-lyase was demonstrated to be widely distributed in woody plants.

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Curdlan is produced by a mutant of Alcaligenes faecalis var. myxogenes, strain 10C3. The nature of its gel formation was investigated. The polymer formed a firm, resilient gel when heated in aqueous suspension at or above 54°C. An aqueous suspension (2%) of the polymer gave 730 (g/cm²) gel strength when heated at 90°C. The gel strength was independent of the incubation time but dependent upon the temperature. The presence of borate alone greatly increased the gel strength. The gel strength did not change between pH 2.5 and 10. The addition of urea, a reagent which breaks hydrogen bonds, caused a decrease in the gel-forming temperature, the extent of decrease depending upon the concentration of urea. X-ray studies indicated that heat-treatment of the polymer suspension caused a change in the molecular arrangement.

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The separation of carbohydrates and cyclitols by gas-liquid chromatography of their trifluoroacetyl (TFA) derivatives is described. TFA derivatives are readily formed in formamide containing sodium trifluoroacetate and trifluoroacetic anhydride without heating so that the chromatographic analyses can be made in a short time. Conditions are described for the chromatography of variety of carbohydrates including the mono- and disaccharides, simple glycosides, aminosugars, and cyclitols. The analyses have been made mostly with a silicone column (SE-52) and a fluorosilicone column (QF-1). Isothermal conditions are usually employed, but for a mixture with components of widely differing molecular weight, linear temperature-programmed procedures are performed.

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This paper constitutes the first report in a research series undertaken in order to clarify the interactive relationships among soybean meal protein, calcium and phytic acid in solution and in precipitate.
Data presented are mainly concerned with solubility characteristics of soybean meal proteins as a function of pH. The results support the suggestion as follows; phosphorus and calcium give the remarkable effects on solubility characteristics of protein, the com-plex containing protein, calcium and phosphorus is formed above isoelectric point of protein and the combinations are labile above at pH 8, especially by heating.

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Four types of cellulases, FI-1-b, FI-2-b, FI-2-c, and FII, were obtained from a commercial crude cellulase preparation produced from a water extract of a culture of A. niger.
Ammonium sulfate fractionation and column chromatography using DEAE-Sephadex A-25, Amberlite IRC-50 and Hydroxylapatite were employed for the purification of these cellulases.
Some properties of these enzymes were investigated: the optimum pH for the hydrolysis of glycol cellulose by FI-2-b and FI-2-c was pH 4.0 to 5.0, while that of FI-1-b was pH 2.3 to 2.5, and the optimum temperature for the activity of FI-2-b and FI-2-c was 40°C, but that of FI-1-b was 65°C.
The FII seemed to be most active toward cellobiose. Studies of the mode of action on glycol cellulose indicated that A. niger cellulases seemed not to be capable of attacking highly polymerized cellulose.

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Discussions were made on the effects of oxygen supply at the growth phase and the production phase in glutamic acid fermentation. The following points were clarified:
(1) In the production phase, deficiency of oxygen supply resulted in the less product formation and high aeration did not exert harmful effects.
(2) In the growth phase, deficiency of oxygen supply scarcely resulted in the less product formation if sufficient aeration was attained at the subsequent production phase and high aeration yielded the cells which were practically incapable of forming glutamate under any aeration conditions at the produc-tion phase.
(3) From these findings, the existence of the optimum condition of aeration in glutamic acid fermentation was explained.

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A system for the automatic control of oxygen pressure of gas- or liquid-phase in flasks was developed for shaken cultures. Electrolytic oxygen was utilized in this system and the control was performed by regulating the electric current passed through the electrolytic cell. Measurement of the quantity of electricity proved to give the rate of oxygen transfer.
No inhibitory effects of electrolytic oxygen were noticed without any purification procedure, and glutamic acid fermentation proceeded smoothly. In the glutamic acid fermentation under controlled pressure of dissolved oxygen, the critical level of dissolved oxygen for product formation was very low. This result was similar to that observed in the culture where dissolved oxygen was not controlled constant.

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Micrococcus sodonensis KY 3765 and Arthrobacter citreus KY 3155 were found to be capa-ble of accumulating an appreciable quantity of IMP on media supplemented with hypoxanthine as a precursor. Inosine was also produced from hypoxanthine by both cultures during a later stage of fermentation. In A. citreus adenine was converted into hypoxanthine and inosine.
The requirement of high concentrations of phosphate and magnesium salts was demonstrated for high yields of IMP. Manganese deficiency in media was also essential for IMP accumulation by two organisms. Excessive Mn⁺⁺ levels stimulated growth and inhibited IMP production markedly.
In M. sodonensis_??_ribose-5-phosphate-like substance, 5-phosphoribose pyrophospho-kinase and IMP pyrophosphorylase were leaked out of cells grown in suboptimal Mn⁺⁺ levels and the excretion was inhibited in high levels of Mn⁺⁺. Such phenomenon was not noticed in A. citreus.
Similar Mn++ effects were also seen in IMP fermentation on defined media with an adenineless mutant of Corynebacterium glutamicum.

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Pichia quercibus Phaff et Knapp produced xylitol and D-xylonic acid by aerobic dissimilation of D-xylose at good yield of 40% of sugar consumed. The products were isolated from the fermented broth and identified. It would be interesting that both of xylitol, a reduction product of D-xylose, and D-xylonic acid, an oxidation product, are accumulated in the fermented broth.

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The alkaline proteinase of Aspergillus sojae was isolated in gram quantities as a homo-geneous form. The purification procedures were, (1) batchwise-treatment with ion exchange resin Duolite CS 101, (2) fractional precipitation with ammonium sulfate, (3) precipitation with acetone, (4) column chromatography on DEAE-cellulose, and (5) gel filtration with Sephadex G-100. The recovery of the activity was about 12%. The purified enzyme preparation was found to be homogeneous by several criteria such as ultracentrifugation, paper and moving-boundary electrophoreses, etc. Any kinds of carbohydrate and phosphorus were not detected in this preparation, suggesting that this enzyme is a simple protein.

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Synthesis of the C-10 epimer of racemic desoxogibberic acid is described.

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