Dihydrodipicolinate (DDP)^* synthetase and DDP-reductase were partially purified about 30 and 15 folds, respectively, from sonic extracts of Breoibacterium flavum.
In contrast with DDP-synthetase from Escherichia coli, the B. flavum enzyme was only slightly inhibited by α, ε-diaminopimelate, a precursor of lysine, but not by lysine itself. Single or simultaneous addition of any other amino acid (s) of aspartate family did not affect the activity significantly. Optimum pH for DDP-synthetase was 8.4 with Tris-HCI buffer. Kms for aspartic-β-semialdehyde and pyruvate at pH 7.5 were 2×10^-4M and 1×10^-4M, respectively. The formation of DDP-synthetase was not significantly repressed by lysine.
DDP-reductase of B. flavum required NADH or NADPH as the cofactor. This enzyme was not inhibited by single or simultaneous addition of aspartate family amino acid (s).
From the above results, the regulation mechanism of lysine biosynthesis in B. flavum was discussed.

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During the investigation of petrochemical-utilizing microorganisms, two strains (EGB-l7b, EGB-24b) were found to produce two kinds of exocellular polysaccharides from ethanediol.
From the results of taxonomical studies, the strains EGB-17b and EGB-24b were named to Arthrobacter simplex (Jensen) Lochhead var. viscosus n. var. Namely, the strain EGB-17b was very similar to the strain EGB-24b in taxonomy.
But main components of the polysaccharide produced by the strain EGB-17b were rhamnose, mannose and glucose, while main component of the polysaccharide produced by the strain EGB-24b was glucose.
The maximum yield of the polysaccharide produced by the strain EGB-17b was 10.6g/liter, while the maximum yield of the polysaccharide produced by the strain EGB-24b was 6.3g/liter after the investigation of cultural conditions.

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Three isocoumarin compounds (BV 1, 2 and 3) were isolated from the cultural broth of Aspergillus oniki 1784. BV 1 was mellein (3-methyl-8-hydroxy-3, 4-dihydroisocoumarin). BV 2 and 3 were assigned to be 3-methyl-4, 8-dihydroxy-3, 4-dihydroisocoumarin, 3-methyl-3, 8-dihydroxy-3, 4-dihydroisocoumarin, respectively. These two compounds (BV 2, 3) were newly isolated. Also another component named BV 4 was proved to be 6-methylsalicylic acid.

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Biological availability of 54 aliphatic acids was compared by mini-test with chicks. Availability of saturated fatty acids with carbon chain between 6 to 12 and of lactic, pyruvic, succinic, L-malic, fumaric and citric acid was satisfactory Availability of fatty acids with carbon chain shorter than 6 and longer than 12, fatty acids with side-chain, except those of iso-type and unsaturated fatty acids was low. Availability of glycolic, DL-glyceric, DL-malic, and maleic acid, and saturated diearboxylic acids except succinic acid was also low. Digestibility of saturated fatty acids with carbon chain length longer than 8 decreased inversely with the increase of carbon chain length.

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Biological availability of 23 alcohols, 16 aldehydes and 2 ketones was compared by the mini-test with chicks. Chicks can utilize methanol and ethanol, but not the alcohols of carbon chain from 3 to 9. Lauryl and myristyl alcohols were well utilized but those of higher carbon chain than 14 were not, mainly due to low digestibility. Glycerol and D-sorbitol were well utilized but not 4 other poly alcohols tested. Aldehydes and ketones with free carbonyl group showed low availability or even toxicity, but their derivatives with masked group showed no detrimental effect. Acetaldehyde, acetal and aldehydes of carbon chain longer than 9 were partially utilized.

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Biological availability of 33 esters, 17 ethers and 2 acetals of ethanediol, 1, 2-propanediol, 1, 3-butanediol and 1, 4-butanediol was compared by mini-test with chicks. Chicks can utilize esters of ethanediol, 1, 2-propanediol and 1, 3-butanediol with acetic acid and fatty acids of carbon chain length from 5 to 12 with more improved palatability than that of free acids, while availability of esters of these glycols with propionic and butyric acids was low. Esters of 1, 4-butanediol and ether derivatives of these glycols was not available, except ethyl ether of di-ethanediol which was partially available. Acetacetal of ethanediol was partially available but n-butyracetal was not.

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Five substances, water soluble organic sulfur compounds, produced from dibenzothiophene by such bacteria as Pseudomonas jianii or Ps. abikonensis were isolated from culture broth. Three products of them were identified as 3-hydroxy-2-formyl-benzothiophene, di-benzothiophene-5-oxide and 3-oxo-2 [3'-hydroxy-thionaphthenyl-(2)-methylene]dihydrothiona-phthene respectively.

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A new attempt was proposed to prepare protein-like food products free from unfavorable odor, taste and color, through the peptic proteolysis and subsequent plastein synthesis. Protein concentrates from soybean, codfish, chlorella, wheat, milk, baker's yeast and hydrocarbon-assimilating yeast were used as the materials. When each protein concentrate was partially hydrolyzed with pepsin, the odorants, fats, coloring substances per se existing in the protein concentrate were liberated and removed by the ether extraction. However, the resulting proteolyzates were bitter. When the bitter proteolyzates were incubated with α-chymotrypsin, some higher-molecular protein-like substances (plasteins) were formed which were almost bitterless and had little if any unfavorable odor, taste and color. Various enzymes were tested for their aptitude to produce a soy plastein from a peptic proteolyzate of soy protein; two commercial proteinases (Bioprase and Prozyme) were found to be as highly plastein-productive as α-chymotrypsin.
Deta were presented substantiating the above descriptions.

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Soy protein (hydrochloric acid-precipitated fraction) was hydrolyzed with pepsin until the 10% trichloroacetic acid insoluble fraction in the resulting hydrolyzate reached 20% by weight. The hydrolyzate was incubated with a microbial protease (Bioprase) to obtain soy plastein. The soy plastein contained 13.22% nitrogen on dry basis and its constituent amino acid composition was similar to that of the original soy protein. Based on the essential amino acid (EAA) pattern in the soy plastein, its chemical scores were obtained as follows: protein score, 76 (S-containing amino acid); milk score, 67 (leucine); and egg score, 60 (S-containing amino acid). Pepsin and trypsin digestibilities in vitro of the soy plastein were 84.8% and 76.5%, respectively, which were almost the same with those of the denatured soy protein. The bio-utility evaluation in rats fed on the soy plastein diet showed the following results: true digestibility, 90.3%; biological value, 66.8; and average weight gain, 27.4g/20 days which increased to 68.8g/20 days by supplementing amino acids according to the EAA pattern in casein. These values in the soy plastein were also similar to those in the soy protein.

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Soy proteins were incubated with a microbial acid protease (Molsin) under the following condition: substrate concentration, 1%; enzyme-substrate ratio (by weight), 1/100; pH, 2.8; and temperature, 40°C-flavor components and related impurities are removable from crude soy-protein concentrates by their incubation for 2 hr under the above condition. The acid-precipitated fraction of soy protein incubated for 2 hr with Molsin (i.e. 2 hr-proteo-lyzate) showed the following composition: 1000 trichloroacetic acid (TCA) insoluble fraction, 47.52%; 10%TCA soluble peptide fraction, 52.02%; and free amino acid fraction, 0.46%. Gel filtration of the 2 hr-proteolyzate gave an elution pattern showing its molecular weight distribution.
In the process of the incubation of the acid-precipitated protein, the 10% TCA insoluble fraction showed increase in amino nitrogen content, its solubility in a phosphate buffer increased to change at 6 hr, and a hydrophobic amino acid share in this fraction increased gradually.
In vitro digestibility of the acid-precipitated fraction were improved and the lipoxygenase activity in this fraction decreased through the Molsin treatment.
Ultracentrifugal analysis showed a decreasing tendency of the cold-insoluble fraction of soy protein during its incubation with Molsin. Optical rotatory dispersion and circular dichroism study elucidated conformational changes in this fraction during its incubation either with or without Molsin.

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From view point of the study on LET effects on bacteria, log- and stationary-phase cells of M. radiodurans, an extremely radioresistant vegetative bacterium, suspended in the phosphate buffer were exposed to 26 MeV α-particles from the IPCR cyclotron. The results obtained were compared with those on γ-irradiation. On such liquid-phase irradiation, survival curves of M. radiodurans for α-particles were found exponential while they were of sigmoidal or cumulative type for γ-rays. In addition, the dose-rate effect was observed with α-bombardment, although it was not found with γ-irradiation. For a given dose and in a system where the effective volume was sufficiently small as compared with the total sample volume, the relation of the surviving fraction S to the beam intensity I was represented by an empirical equation, S-exp[-(It/q0){1-exp(-kq0/I)^p}] where t is irradiation time, q₀ is D₃₇, and k and p are constant. By means of sedimentation analysis, double-strand scissions in DNA caused by α-particles were found repairable during the postirradiation incubation similarly to the case of γ-irradiation. The findings observed here with M. radiodurans do not support the view that DNA is an only primary target for cell killing by α-particles.

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Intermediate and high boiling neutral compounds in the aroma concentrate from black tea were isolated by fractional distillation, silica-gel column chromatography and gas chromatography.
Identification of the compounds was verified by the agreement of IR and mass spectra as well as gas chromatographic data with those of authentic compounds.
Eleven compounds; α-muurolene, δ-cadinene, furfuryl alcohol, methyl phenyl carbinol, cadinenol, geranial, pyrrole-2-aldehyde, benzyl formate, phenylethyl formate, cis-3-hexenyl benzoate and indole, were newly identified as constituents of black tea aroma and ten known components; α-terpineol, 3, 7-dimethyl-1, 5, 7-octatrien-3-ol, trans, trans-2, 4-decadienal, 2-phenyl-2-butenal, α- and β-ionone, cis-jasmone, theaspirone, lactone of 2-hydroxy-2, 6, 6-trimethylcyclohexylidene-l-acetic acid and phenylacetonitrile were confirmed. The geometric structure of theaspirone in tea aroma was determined as the cis-form.

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The lipase from Candida paralipolytica was purified, as judged by disc electrophoresis. The purification was about 132 fold, based on protein, with a recovery of 32% from the acetone precipitate of the cultivated broth.
After purification, modification of the enzyme was performed by dialyzing its solution against 1 M sodium chloride in acetate buffer at room temperature and by separating the modified enzyme from an unknown substance (s) with a Sephadex G-75 column.
The optimum pH for lipolysis of the purified lipase was 8.0, while that of the modified one was 7.0. Sodium taurocholate was required essentially by the purified enzyme, but not by the modified one. The purified lipase was stable below 37°C and in the pH range from 3.5 to 9.0 at 5°C.

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It has been suggested by Sokal and Sneath that the mathematical techniques used in numerical taxonomy would effectively be applied to elucidate serological (and perhaps phylogenetic) relations among organisms. This excellent idea, however, has hitherto never come into operation. The present paper describes a mathematical method for analyzing the intensities of antigen-antibody reactions between test organisms to make clear their serological relations. Eighteen corynebacteria were examined as a test case, and a brief discussion is presented on the results obtained.

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In order to elucidate the protease constitution of Aspergillus oryzae, systematic separation of proteases was elaborated by sequential chromatography on Amberlite CG-50, DEAE-Sephadex A-50 and CM-cellulose. As the results, three kinds of proteases, that is, acid-, neutral- and alkaline proteases were isolated and purified in crystalline form except neutral one. Purified neutral protease could not be crystallized, but was confirmed to be homogeneous by ultracentrifugal analysis. Besides these proteases, a new protease which was unknown up to the present in the constitution of Asp. oryzae proteases, was first isolated and designated as “semi-alkaline protease” according to its optimal pH.

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Several analogs of abscisic acid (ABA) were prepared and their biological activities were assayed. Among the compounds tested, 5-(1, 2-epoxy-2, 6, 6-trimethyl-l-cyclohexyl)-, 5-(1-hydroxy-2, 6, 6-trimethyl-2-cyclohexen-l-yl)-and 5-(1-hydroxy-2-methylene-6, 6-dimethyl-1-cyclohexyl)-3-methyl-cis, trans-2, 4-pentadienoic esters (V, IX, XXIII and XXV) were found to be potent plant growth inhibitors. Their activities were superior or comparable to that of ABA.

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Fumaric acid productivity of Candida hydrocarbofumarica in various culture conditions was investigated. Namely, the effects of pH, heavy metal ions, hydrocarbon concentration. aeration and surface active agents were studied.
The addition of CaCO₃ and the aeration were effective for fumaric acid production.
The rate of conversion of n-paraffin to fumaric acid gradually decreased as the concentration of n-paraffins (6%) was increased.
A very high yield, 84% was obtained with a culture medium containing 6% of n-paraffins for 7 days culture.

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Oligosaccharides terminated by radioactive sucrose at the reducing end of maltooligosaccharides have been used in the oligosaccharide mapping procedure for characterizing α-amylases. The action patterns of ten α-amylases from various origins were investigated with this mapping method and compared with the results with normal maltooligosaccharides. The experimental results indicated that Bacillus subtilis saccharifying, Endomycopsis and pancreatic α-amylases had similar action patterns toward oligosaccharides with or without fructose at the reducing end. However, the action patterns of other seven α-amylases were somewhat different.

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