The distributions of protein, calcium and inorganic phosphate among casein micelles of skimmilk before and after frozen storage were investigated by gel filtration through Sephadex G-200 with 6.6M urea solution as eluant.
The results showed that the native casein micelles were fractionated into two fractions. Fast eluting fraction contained large amount of calcium and inorganic phosphorus. Slow eluting fraction contained calcium but was essentially free of inorganic phosphorus. Frozen storage caused the increase of proportion of the fast eluting fraction accompanying the increase of calcium and inorganic phosphorus contents in it. It is suggested that the salt linkage newly formed during frozen storage causes the increase of proportion of the fast eluting fraction.

View full abstract

Strand scissions in DNA of M. radiodurans after in vivo irradiation with ⁶⁰Co gamma rays were investigated by the sedimentation analysis using neutral sucrose gradients. Doublestrand scission in DNA was estimated to occur at the rate of one double cut per 800 eV. This rate is in a good agreement of the value reported for mammalian cells. The rejoining of these double-strand scissions was observed during the repair process of the postirradiation incubation and the mean rejoining time, i.e., the time reducing the remaining fraction of the double-strand scission to 0.37, was found to be 52min. This rejoining repair was inhibited by adding chloramphenicol, tetracycline or actinomycin D to the postirradiation incubation medium. It is suggested that the high resistance character of M. radiodurans to gamma rays may be due to the efficient capacity of this rejoining repair.

View full abstract

Five anhydrogalactose-containing polysaccharides have been extracted in high yields with hot water and dilute alkali from Gloiopeltis furcata and purified by precipitation with cetylpyridinium chloride and by some chromatographic techniques. The analytical results showed that they all contained galactose, 3, 6-anhydrogalactose and sulfate residues in the molar ratio of approximately 6:3:4 and in addition, gradually variable amounts of uronic acid residue and protein.

View full abstract

A simple purification method which enables us to obtain homogeneous proteinase C from S. cerevisiae was developed. Physical and chemical properties of the purified enzyme were determined. The extinction coefficient at 280mη, E^1%_1cm, of yeast proteinase C was 14.8, and its isoelectric point was pH 3.60. Partial specific volume, intrinsic viscosity and the sedimentation and diffusion coefficients of homogeneous protein were_??_, 0.71ml/g, [η], 4.83×10^-2ml/g, s⁰_{20, w'} 4.23 S and D⁰_{20, w'} 6.1×10^-7 cm²/sec. From these values, molecular weights, M_{[η], D,} M_{S, D} and M_{[η], S}, of 60000, 59000 and 58000, respectively, were obtained. The sedimentation equilibrium experiment gave a molecular weight, M_equil, of 61000. Yeast proteinase C contained 11.9% nitrogen and was a glycoprotein with 16.7% carbohydrate: The value of β-function, 2.163×10⁶ or 2.20×10⁶ indicates that the molecular shape of yeast proteinase C is a plorate with an axial ratio of 4.0, assuming 35% hydration. Furthermore, yeast proteinase C may be a compact, asymmetric ellipsoidal model having semi-axes 30Å×30Å×130Å.

View full abstract

Wild-type phage Jl of Lactobacillus casei was found to be temperature-sensitive; the phage failed to grow at 40°C, though the host bacteria grew normally at that temperature.
An analysis of phage growth at 40°C revealed the following. (i) Free phage particle was thermostable. (ii) The adsorption of phage led to the penetration of phage DNA. (iii) No lysis of infected cells occurred, but this was not w major block. (iv) No mature phage particle was formed in the infected cells. (v) No phage-related protein was formed in the cells. (vi) The temperature-shift experiment and the radiobiological study indicated that an early stage of intracellular phage growth was blocked.

View full abstract

The rice koji for sake making usually shows white, but sometimes, during storage in the air it turns brown. This turn is accelerated by some wet conditions.
Three kinds of precursor of the pigment in browned rice-koji were isolated in the present work by column chromatography. A main precursor was adsorbed on alumina at pH 8.5 and eluted with 0.3N acetic acid. The eluate was then treated by Dowex 50-X8 (H) column, eluted with water and 1 N HCl, and then identified as L-dopa after derived to 3, 4-di-O-benzoyl-N-benzoyl-L-dopa ethyl ester. The second precursor was isolated from ethylether soluble fraction of the water eluate described above and identified as protocatechuic acid by some chemical properties. The third precursor was not isolated owing to its chemical unstableness, though it was clearly different from these two precursors.
Isolation of L-dopa from the rice koji made by culture of Aspergillus and also from sake and sake cake was first carried out in the present work.

View full abstract

An enzyme preparation from glutinous millet grains has been found to synthesize various riboflavin glycosides from riboflavin and disaccharides other than maltose (such as cellobiose, melibiose and lactose). Each of these riboflavin glycosides has been isolated in crystalline form and shown to have the structure, 5'-D-riboflavin-β-D-glucopyranoside, 5'-D-riboflavin-α-D-galactopyranoside and 5'-D-riboflavin-β-D-galactopyranoside.

View full abstract

Screening test for obtaining growth stimulant (GS) produced by a hydrocarbon-utilizing bacterium, Pseudomonas aeruginosa S₇B₁, was carried out. In consequence, the anthrone positive substance was most effective on the growth of this strain. Although the growth of this strain on glucose medium had no relation with the addition of GS, the growth on n-hexadecane medium was remarkably stimulated by the addition of GS. This effect of GS seemed to be specific on the growth of P. aeruginosa. GS which had a strong surface activity and emulsifying power was comfirmed to be rhamnolipid.

View full abstract

Distribution of tetramethylpyrazine(T. M. P.) in Japanese fermented foodstuffs was investigated by more accurate analytical method.
Namely, the method was successful when trapping T.M.P. with picric acid after flash evaporation of the foodstuffs, followed by analysis with gas chromatography.
T. M. P. was detected in many Japanese fermented foodstuffs, especially in Miso, Soy sause and Natto, which suggests that alkylpyrazines may play an important role as flavor of those foodstuffs.

View full abstract

Tadpoles of Japanese toad (Bufo vulgaris) were cultured by an artificial feed and by forced cannibalism from the egg until metamorphosis finished. The best growth was found in the artificial feed group, however, the highest feed efficiency was observed in the cannibalism group. The tadpoles were metamorphosed by the culture with amino acid mixture feed but no body weight increase was seen in this case. The nutritional disturbance hindered the metamorphosis.
The relative amino acid composition was constant throughout all the stages of the tadpole growth. The relative amino acid composition of the toad was diversed according to the species. Several unidentified ninhydrine-positive substances were detected on the column chromatograms of amino acid analysis of tadpoles and their adult forms.

View full abstract

The effects of cyclic adenosine 3', 5'-monophosphate (c-AMP) on carbohydrate metabolism, especially gluconeogenesis, glycolysis, glycogenesis, and glycogenolysis in rats fed a stock diet (commercial pellets) were investigated. Increases in blood glucose levels in rats injected with two different doses of c-AMP intraperitoneally were observed. The rates of increase in blood glucose levels of rats administered 20mg of c-AMP per 100g of body weight were higher than those of rats administered 2mg of c-AMP per 100g of body weight. In vivo gluconeogenic capacity was increased by the injection of either dose of c-AMP. In vivo glucose oxidation was depressed and liver glycogen levels were decreased in rats administered 20mg of c-AMP per 100g of body weight but these changes were not recognized in rats administered 2mg of c-AMP per 100g of body weight. Renal gluconeogenesis was merely stimulated by the injection of the lower dose of c-AMP. Glucose formation from FDP and/or FDP in both liver and kidney cortex homogenates of rats was not stimulated by the injection of c-AMP.

View full abstract

The proteinase inhibitors I (R-I) and III (R-III) isolated from Japanese radish seed were characterized in terms of their N-terminal amino acids, amino acid composition and reacting groups. The amino acid composition of two proteins differed from each other, while histidine, methionine and tryptophan contents were all low. N-Terminal amino acids of these inhibitors determined by Edman degradation were the same; valine.
By modifying free amino groups in the inhibitors with trinitrobenzenesulfonic acid, R-III was greatly inactivated in proportion to the modification of amino groups, but the activity of R-I was not affected.
However, modification of arginyl residues of R-I by cyclohexanedione reduced its activity. These results indicate that R-I is an arginine-type and R-III is a lysine-type inhibitor.

View full abstract

Inhibitors I (R-I) and III (R-III) obtained from Japanese radish seed were employed to investigate their interaction with trypsin. The trypsin-inhibitor complex was isolated by gel-filtration on Sephadex G-75. Second order rate constants of the complex formation were 5.8×106M^-1. sec^-1 and 1.1×10⁶M^-1. sec^-1 for trypsin-R-I and trypsin-R-III, respectively. The complex dissociated in an acidic pH range (pH 2_??_5) and the dissociation constant was dependent on pH. pH-dissociation curves were sigmoidal. The K_diss. value at pH 8 was approximately calculated as 10^-10M. The R-III-trypsin complex was also dissociated (by treatment with protein denaturants and by heat treatment, ) in proportion to inactivation of the enzyme.

View full abstract

The purification of ricin was reinvestigated. Ricin can be purified by CM-cellulose column chromatography at pH 6.5, followed by gel filtration on Sephadex G-75 at pH 8.0 and finally CM-cellulose column chromatography at pH 7.0. The purified ricin preparation is electrophoretically and ultracentrifugally homogeneous and identical with ricin D in sedimentation coefficient and toxicity. The effects of cupric ion on the solubility and the behavior in CM-cellulose column chromatography of ricin were examined. The purified ricin was precipitated with copper acetate at higher concentrations than 10^-5M and the crystallization of ricin was achieved by dialysis against 0.005M phosphate buffer con-taining 10^-6M of copper acetate at pH 6.5.

View full abstract

Amino acid analysis of ricin D was carried out with an automatic amino acid analyzer. The following composition was determined: Asp₅₉Thr₃₅Ser₃₇Glu₄₆Pro₂₆Gly₃₆Ala₃₇Val₂₉Ile₃₅ Leu₄₂Tyr₂₀Phe₁₈Lys₉His₆Arg₃₂Met₆l/2Cys₁₂Try₈ indicating that ricin D contains approximately 493 amino acid residues. The molecular weight of this protein was calculated to be about 55000 agreeing well with the value obtained earlier by Archibald's method.
The C-terminal amino acids determined by carboxypeptidase A and by the hydrazinolysis technique were found to be serine (0.90 mole/mole) and phenylalanine (0.58 mole/mole).
The N-terminal amino acids measured by DNP-method of Sanger proved to be alanine (0.90 mole/mole) and isoleucine (0.52 mole/mole).

View full abstract

Lipase extracted from defatted rice bran with calcium chloride solution was purified by ammonium sulfate precipitation, followed by successive column chromatographies on DEAE-cellulose, Sephadex G-75, CM-Sephadex C-50 in the presence of calcium ion. The specific activity of the purified enzyme was 4.7 units/mg protein and 480 times that of starting crude extract. The homogeneity of the enzyme protein was criticized by polyacrylamide gel disc electrophoresis and ultracentrifugation. The enzyme protein also behaved homogeneously in ampholine electrophoresis, indicating the isoelectric point of 8.56. The sedimentation coefficient of the enzyme was determined to be 2.97 S, and the molecular weight to be 40000 by Archibald's method. According to the measurement of optical rotatory dispersion of the enzyme, ORD constant, λ_c, Moffitt-Yang parameters, a₀ and b₀, were evaluated to be 239mμ, , -164 and -123, respectively.

View full abstract

Crystalline L-asparaginase from Escherichia coli A-1-3 hydrolyzed D-asparagine, L- and D-glutamine but at much slower rates than the rate at which it hydrolyzed L-asparagine. Inhibitions by these substrates and related compounds were revealed to be competitive.
D-Asparagine showed the same affinity for the enzyme both in its hydrolysis and in-hibition of L-asparagine hydrolysis. L-Aspartate, D-aspartate and α-N-ethylasparagine in-hibited various hydrolysis reactions with the respective inhibitor constants. The enzyme was found to hydrolyze β-methylaspartate as well as β-aspartohydroxamate. These data strongly suggest that the hydrolysis occurred at the same active site of the enzyme molecule with relatively low specificity for the configuration of the substrate molecule and the kind of bonding which it hydrolyzes

View full abstract

d-Oxybiotin (X) was synthesized from D-glucose and showed biotin activity for some microorganisms.

View full abstract

The volatile compounds from beef fats heated under the cooking condition-145°C, 10 min-were isolated, and nonacidic compounds separated from them were further fractionated into five fractions by silicic acid column chromatography. The odor of nonacidic compounds significantly resembled the heated flavor of beef fats. Several carbonyl compounds, hydrocarbons, alcohols, lactones and pyrazine compounds in the fractionated compounds were identified with the techniques of gas chromatography and gas chromatography-mass spectrometry. Their possible contribution to the heated beef fat flavor was discussed. The typical heated flavor could probably be ascribed to a proper combination of aldehydes, ketones, esters and sulfur-containing compounds

View full abstract

Absorption and metabolism of the herbicide 3-(2'-methylphenoxy)pyridazine (H-722) by susceptible (barley) and tolerant (tomato) plants were investigated with a tritium labeled chemical to obtain fundamental information on residue analysis as well as on selective action. Four metabolites were clearly detected, for which chemical structures were assigned, except a minor one. They were 3-(2'-methylphenoxy)pyridazine-l-oxide, 3-pyridazinone-(2H) and 3-(1-β-D-glucosyloxy) pyridazine. The fate and behavior of o-cresol which should be a metabolite resulting from cleavage of the aromatic ether linkage in H-722 is considered a key to the mechanism of the herbicide's selective action.

View full abstract