It was confirmed that turbid substances which remained in saccharified liquid after digestion of starch slurry with bacterial alpha-amylase and glucoamylase were insoluble starch particles and that these materials were formed during heat treatment of the slurry in liquefaction process.
In iodine staining reaction, the suspension of these materials showed only u slightly dirty blue color; even after boiling of this suspension for 30 min at 135°C, this staining reaction was not complete and the maximum color intensity could be obtained after treat-ment with 1 N caustic soda solution.
It is assumed from the iodine color reaction, that the main component of these materials was glucose polymer of straight chain, like that of amylose, and that this would be strongly associated with each other to form the compact molecule.
The method for determination of these insoluble starch particles in the starch slurry was established and by this method the contents of these materials were determined in some types of starches.

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The dynamic modulus and dynamic viscosity of the potato starch solution in 1 N KOH, 2.0g to 7.0g/100 ml, were measured with a forced torsional vibration rheometer at various frequencies at 25°C. The starch solutions irradiated by gamma ray were also measured similarly.
The master curves of the dynamic modulus and dynamic viscosity were derived ac-cording to Ferry's time-concentration reduction principle. The concentration dependences of the dynamic modulus G'∝C^m, the dynamic viscosity η_d∝C^n', and of the zero angular frequency viscosity η/η_O∝Cⁿ were determined.
The relaxation spectra of starch solutions were obtained as curves of nearly linear shape and those of the irradiated starch solutions shifted to shorter relaxation time with steeper inclinations.

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Thiosulfate was oxidized to tetrathionate and an unknown oxidized sulfur compound. The activity was found in the particulate fraction (a precipitate obtained by centrifuging (at 90, 000 ×g for 60min) the supernatant of centrifugation at 10, 000 ×g for 30min). Treatment with deoxycholate caused inactivation of the enzyme. Considering from these points and electronmicrograph, the enzyme would be located on the cell membrane.

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By the application of various genetical techniques, a number of guanosine and inosineproducing mutants were obtained from a Bacillus strain. The indispensable genetic characters of the mutants concerning with guanosine productivity were adenine requirement, lack of GMP-reductase and mutation to adenine and adenosine resistance from adenine and adenosine sensitiveness. Main products of these mutants were guanosine and inosine. Their culture broths also contained hypoxanthine, xanthine and sometimes u little guanine and xanthosine. Furthermore a few unknown nucleosides were also detected. The yields of guanosine were about 5mg/ml in 4-day culture broths.

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Chicks were fed on the purified diets of which amino acid pattern was modeled after whole egg protein and crude protein content was 21.1%, changing the dietary ratio of indispensable amino acid nitrogen to dispensable amino acid nitrogen (I/D ratio) from 1/1.5 to 3/1 at regular intervals. The balances among amino acids in each indispensable and dispensable group of test diets were kept the same pattern as that of the whole egg, respectively. Optimum I/D ratio for normal chick growth was estimated to be in the range of between 1/1 and 1.5/1, because feed efficiency was the highest at the I/D ratio 1/1 and growth rate was the highest at the I/D ratio 1.5/1.
Chicks were killed and the serum was collected at the end of the experiment. It was shown that the I/D ratios of free amino acid in the serum of chicks were strongly influenced by that of diet.
White Leghorn chicks fed on the Scott's reference amino acid diet grew as well as those fed on a conventional chick starter. Nitrogen retention of the former was a little less than that of the latter, but the amount of carcass fat of the former was almost twice as much as the latter.
Growth rate of chick was considerably reduced, when glutamic acid which is the only dispensable amino acid in the Scott's diet was replaced by a mixture of glutamic acid, aspartic acid, alanine and serine, nitrogen content being kept at constant. Sufficient amount of glutamic acid in the Scott's diet seems to be essential for the maximum growth of chick.

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Polyol dehydrogenases of Acetobacter melanogenum were investigated. Three polyol dehydrogenases, i. e. NAD⁺-linked D-mannitol dehydrogenase, NAD⁺-linked sorbitol dehydrogenase and NADP⁺-linked D-mannitol dehydrogenase, in the soluble fraction of the organism were purified 12-fold, 8-fold and 88-fold, respectively, by fractionation with ammonium sulfate and DEAE-cellulose column chromatography. NAD⁺-linked sorbitol dehydrogenase reduced 5-keto-D-fructose (5KF) to L-sorbose in the presence of NADH, whereas NADP⁺-linked D-mannitol dehydrogenase reduced the same substrate to D-fructose in the presence of NADPH. It was also shown that NAD⁺-linked D-mannitol dehydrogenase was specific for the interconversion between D-mannitol and D-fructose and that this enzyme was very unstable in alkaline conditions.

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The formation and the bactericidal action of colicin B, which had not been studied, were examined. When colicin B-producing cells were incubated with a low concentration of EDTA in' water at 37°C for 30 min, almost all of colicins were extracted from cells into the surrounding medium. This technique was extremely effective for colicin I, which was not excreted into medium under usual conditions.
Colicin B inhibited many macromolecular functions in the sensitive E. coli cells simultaneously, i.e., O₂ uptake, oxidative phosphorylation, permeation activity for o-nitro-phenyl β-galactoside (ONPG) through cell membrane, and syntheses of protein, RNA and DNA.
Colicin B could not be distinguished from colicin K by the cross-immunity test using K-colicinogenic strains. Colicin B had also many resemblances in the mode of action to colicine K, although their action was observed to be different in some points. These results indicated close relationship between colicins B and K.

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The irreversibility of the dissociation of “myosin B” stored in 0.6 M KCl at pH 5.7 and 3°C was attributed to the rapid denaturation of F-actin dissociated from “myosin B”
F-Actin was less stable than myosin A, in 0.18_??_0.60 M KCI at pH 5.7 and temperatures between 0-3°C.
The decrease in the ability of F-actin to bind with myosin A was slightly dependent on storage temperature, and there was no apparent relation with the decrease in the solubility.
A hypothetical scheme for F-actin denaturation was proposed.

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Four deoxyribonucleoside monophosphokinases were studied with extracts prepared from pupae of silkworm infected and uninfected with nuclear polyhedrosis virus (NPV).
An increase in dTMP and dCMP kinase activities was observed in pupa 24 hr after the infection. The increase amounted to 2.0- and 1.5-fold, respectively. The enzymes in infected and uninfected pupae have the same pH optimum. dTMP and dCMP kinases were recovered in 35 to 50% and in 50 to 8040 ammonium sulfate fractions, respectively. Moreover, the later fraction gave also dAMP and dGMP kinase activities. However, no increase in dAMP and dGMP kinase activities was detectable in NPV-infected pupa.
The results obtained suggest that dTMP and dCMP kinases may have an important role in an early stage of the viral DNA replication.

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Data are presented to show the gas chromatographic identification of a total of 18 saturated aliphatic γ- and δ-lactones obtained from melted beef depot fat, namely, _ϒ-C₆, _ϒ-C₇, _γ-C₈, _γ-C₉, and a homologous series of _γ- and δ-lactones of the even-carbon numbers C₁₀ to C₁₆ and of smaller amount of the odd-carbon numbers C₁₁ to C₁₅. These lactones were isolated by steam distillation and silicic acid adsorption chromatography, and identified through gas chromatography and infrared spectroscopy.
Lactones obtained had a peach-like flavor, and it was suggested that lactones were important in heated beef fat as the flavor compounds.

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Effect of angustmycin C, an adenosine analogue having an unusual sugar linked to adenine, on Eecherichia coli was studied. It inhibited biosynthesis of RNA and DNA preferentially and xanthosine was excreted from the inhibited cells into the medium. During the course of its growth with addition of the antibiotic, the specific activity of inosine-5'-phosphate dehydrogenase of E. coli cells increased six times. These effects could be explained by the inhibitory effect of angustmycin C on xanthosine-5'-phosphate aminase which resulted in decreased level of IMP-dehydrogenase. Accumulation of xanthosine induced by the antibiotic reached the concentration of 940μg/ml under an appropriate condition.

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A nucleosidic antibiotic angustmycin C, which is an analogue of adenosine and which has an unusual hexose, psicofuranose, instead of ribose, was confirmed to be incorporated into RNA in Escherichia coli. After incubation of cells with tritiated angustmycin C, small but significant radioactivity was found in RNA fraction. When the RNA was hydrolyzed by an enzyme mixture of snake venom, pancreatic ribonuclease I and alkaline phosphatase, intact angustmycin C was recovered which indicated incorporation of the antibiotic intc the polyribonucleotide chain of RNA.

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The influence of the concentration of F-actin on the inactivation of myosin A-ATPase in solution and in suspension has been studied. The reaction departs from typical first-order behavior in that the rate decreases as the reaction proceeds. The extent of this effect varied greatly with the amount of F-actin added and slightly with pH and ionic strength. The interpretation of the experimental results is discussed. A kinetic mechanism which qualitatively accounts for the observed behavior and which suggests the occurrence of two types of actornyosin complexes with respect to susceptibility to denaturation is proposed.
The rate of denaturation of myosin A has been found to decrease greatly on an addition of magnesium and also with a decrease in ionic strength at high (10.3) or low (6.0) pH values.

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Deoxyribonucleic acids were isolated from Breribacterium lactofermentum No. 2256 and its four representative phages belonging to different serological groups, i.e., P465 (group I), P 468 II (group II), Ap 85 III (group III) and P 4 (group IV), by phenol extraction.
DNA's isolated from the four phages contained only usual four bases, i.e., guanine, adenine, cytosine and thymine. The G-C content of the phage DNA was determined by thermal denaturation method (T_m); the values of P 465, P 468 II, Ap 85 III and P 4 were 54.0, 54.6, 56.6 and 55.3%, respectively. Sedimentation coefficient was measured by ultracentrifugal analysis using ultraviolet optics; _{s20, w} of the phage DNA's were 15.5 to 31.8s.
Unusual bases were not detected also in the host bacterial DNA. The G-C content of the bacterial DNA determined by paperchromatography was 55.1% which came very close to the G-C content derived from the T_m.

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Morphological properties of the P- and Ap-series phages described in previous papers were examined by means of electron microscopy, analytical centrifugation, CsCl densitygradient centrifugation and ultrafiltration.
In view of the buoyant density of phage particles, fourteen Brevibacterium phages were classified into four groups, i.e., the phages under group I had buoyant density of 1.511 to 1.514g em^-3, and those under groups II, III and IV, densities of 1.482, 1.492 and 1.508g cm^-3, respectively; and above grouping corresponded to that by the serological chracteristics of the phages.
Electron microscopic observation by means of shadow-casting or negative staining recognized all the phages as tadpole-shaped; their particles having polyhedral head (40-70mμ in diameter) and long tail (80_??_275mμ in length).
In relation to particle sizes of the phages as estimated by all of above-mentioned methods, no significant differences were observed between the sizes calculated from ultrafiltration and those obtained directly from electron micrographs by negative staining.

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A new tropone compound, named nezukone, has been isolated from the wood of Thuja standishii Carr. and shown to possess the Structure (I). It is the first case that a tropone is found in nature.

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