The proposed similarity of conformation between α-lactalbumin (α-LA) and hen egg-white lysozyme was tested by the comparison of the thermodynamic parameters obtained from the temperature dependence of denaturation. For the denaturing reaction by guanidine hydrochloride, the value of ΔC_p for α-LA is almost identical with that for lysozyme, which suggests that the amount of the hydrophobic side chains buried in the interior of the molecule is the same in. the native state; the value of ΔH° and ΔS° for α-LA are also close to those for lysozyme, and the small differences are explicable by the proposed molecular model of α-LA, which implies that the somewhat large difference in ΔG° observed previously between the two proteins does not originate from large conformational differences. These results support the conformational similarity between α-LA and lysozyme as represented by the molecular model. The heat-denatured state of α-LA is also characterized by the parameters and discussed.

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Four fractions with ribonuclease activity have been isolated from tea leaves by DEAE-cellulose column chromatography and designated as RNase Tf-1, RNase Tf-2, RNase Tf-3 and RNase Tf-4. The bigger fractions of both RNase Tf-3 and RNase Tf-4 have been partially purified by Sephadex G-100 column chromatography.
RNase Tf-3 and RNase Tf-4 were respectively found to have their optimum pH at 4.75 and 4.9 and molecular weights of approximately 13, 000 and 16, 000, as determined by gel filtration. Both enzymes were inhibited by Cu²⁺ and Hg²⁺, and inactivated by heating at over 50°C. By addition of yeast RNA to the two enzymes, however, their thermostabilities increased. The activities of the enzymes were stable in a pH range of 4.5 to 6.5. Like other plant RNases, RNase Tf-3 and RNase Tf-4 appeared to have no preference for base in RNA.

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A crystalline phenylhydrazone was obtained when a heated solution of dehydro-L-ascorbic acid (DHA) was treated with phenylhydrazine-HCI. Its molecular formula was C₁₇H₁₈N₄O₂, and the structure was determined to be 1, 2-bis (phenylhydrazone) of 3-keto-4-deoxypentosone, a new tricarbonyl compound which was considered to be one of the possible intermediates of the browning reaction of DHA. 3-Hydroxy-2-pyrone was also isolated from the ether extract of the heated DHA solution as a main aroma compound produced from DHA. Possible formation mechanisms of these compounds were discussed.

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A gram-positive and pleomorphic bacterium (strain 1-42) isolated from soil as a producer of exo-1, 6-α-glucosidase [EC 3. 2. 1. 70] was identified as Arthrobacter globiformis. This Arthrobacter enzyme, inducible by dextran extracellularly, was partially purified from a cell-free culture supernatant. It was found most active at pH around 6.0 and most stable at pH 6.0_??_6.5. The enzyme was proved, by several experiments, to attack dextran in the exo-wise fashion to release only glucose leaving a macromolecular limit dextrandextrin. Transglucosylation from dextran to accumulating or added glucose was not observed.

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A lytic enzyme was isolated from the lysate of Ps. aeruginosa infected with a new strain of bacteriophage, phage 95. The enzyme, LE95, was purified by chromatography in twice on IRC50 column and by gel filtration in twice on Sephadex G-75 column. The molecular weight was estimated as 21, 000. The optimal condition for the hydrolysis of acetone-dried cells of Ps. aeruginosa was determined to be following: the optimal pH was between 6.5 and 7.0, the temperature about 70°C and the concentration of phosphate buffer about 5mM. The enzyme was strongly inhibited by Ag⁺, Hg²⁺, Ni², Fe²⁺ and Cu²⁺ ions. When peptideglycan obtained from Ps. aeruginosa was digested by LE95, free amino groups were liberated without release of reducing sugars. The enzyme was suggested to be amidase or peptidase.

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A new strain of bacteriophage, phage 95, specific to Pseudomonas aeruginosa and Ps. schuylkilliensis was isolated. It has been shown that the phage induces a lytic enzyme which hydrolyzes peptide bond between L-alanine and D-glutamic acid in the peptidoglycan of cell wall.
Here the characteristics of phage 95 are described. It possesses a hexagonal head of 650Å, a contractile tail of 1150 Å and spike with fibers. Its DNA has a GC content of 48%, a density of 1.700g•cm^-3 and Tm of 87.7°C. Photoreactivation was observed. Latent period is 20min and burst size is 50. The phage is stable between pH 5 and 7.5, and unstable above 55°C. Culture condition and 300 liter scale cultivation are also presented.

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Using isolated aleurone particles of rice grains it was found that ADP was easily transformed to ATP. This reaction is likely explained by either a transphosphorylation of a phosphate group from phytic acid to ADP or a mechanism involving adenylate kinase. The optimum temperature and pH for this reaction were 30°C and 7.8 respectively. The apparent Km for ADP was 4.0×10^-4 M. Cyanide arsenate and azide at 10^-3 to 10^-2M had no effect on the ATP formation, indicating that the formation was not due to oxidative phosphorylation.

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When aleurone particles isolated from rice grains were incubated with ³²P-orthophosphate or ³H-myo-inositol, both radioactivities were incorporated into an acid-stable phosphate ester. As the reaction product, myo-inositol monophosphate was recognized by ion exchange column chromatography. The phosphorylation activity was highest at the bran which corresponded to the aleurone layer. These observations suggest that the phosphorylation site of myo-inositol in the rice grain is the aleurone particles.
The phosphorylation of myo-inositol was enhanced by the existence of ATP. The optimum pH and temperature for the phosphorylation were 7.9 and 30°C, respectively.

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Effects of hydrofluorene and hydrophenanthrene compounds derived from dehydroabietic acid on the second leaf sheath growth of rice seedlings were examined in the presence and absence of gibberellin A₃(GA₃). In the absence of GA₃, nineteen compounds at 100 ppm inhibited more than 20% the growth of normal rice seedlings. In the presence of GA₃, (1.5 ppm) with dwarf rice seedlings, nine compounds at 500 ppm suppressed the elongation caused by the hormone, and a compound was slightly promotive. Then, three compounds were selected and subjected to the bioassay under various conditions.

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The nutritional requirements of tobacco crown gall cells (auxin non-requiring cells) in suspension culture were investigated. In the basal medium (Murashige-Skoog inorganic medium), the crown gall cells did not disperse into suspension, growing in various sizes of firm cubic masses of cell aggregates. Individual components of yeast extract which is very effective for both cell growth and dispersion, were added to the basal medium and their effects on cell growth and dispersion were examined. Thiamine was effective for cell dispersion, and myoinositol and nicotinic acid remarkably promoted cell growth. In the basal medium supplemented with these three components, the crown gall tissue grew rapidly being dispersed into a good suspension. An increase of inorganic phosphate in the medium was also very effective for cell growth.

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Cultivation is reported on Aspergillus sojae AJ 7002 which synthesized an extracellular bio-flocculant. Growth studies in shaking flasks and fermentors were conducted to obtain higher flocculant production. The highest level of polymer accumulation was attained after 48_??_72 hr cultivation at 30_??_34°C. The favorable substrates for polymer formation were casein, yeast extract, polypepton and amino acids, such as glutamic acid and alanine. The addition of saccharides to the medium was found to reduce the pH of the culture broths, and hence inhibit the accumulation of flocculant in the culture broth. The finding that the product was a single substance from the early stage of fermentation suggested that the polymer was not a product of cell autolysis. The components of the polymer which were produced by Asp. sojae did not vary even if the medium composition or culture condition changed. The addition of 2-ketogluconic acid, which is one of the constituents of the polymer increased the flocculating activity of the culture medium.

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The spore coat protein of Bacillus subtilis was separated, and the qualitative assay for the spore coat protein was made by use of the immunological technique. The immunological method was found to be useful for judging the maturation of spore coat in the course of sporulation. The spore coat protein antigen appeared at t₂ stage of sporulation. The addition of rifampicin at the earlier stages of sporulation inhibited the increase in content of the spore coat antigen.

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Isolation and some properties of the two components of an Arthrobacter β-1, 3 glucanase (glucanase II-1 and glucanase II-2) are described. Both of these glucanases hydrolyzed various β-1, 3 glucans, accumulating as final products, glucose and laminaribiose. They resembled each other in instability at acidic pH values, lability at temperature above 55°C, having an optimal pH range of 5.5_??_6.5 and requirement of the presence of glucanase I for the effective hydrolysis of yeast glucan. Glucanase II-1 showed a high lytic activity for isolated yeast cell wall, while the activity of glucanase II-2 was low. Culture fluids of early cultures contained glucanase II-1 predominantly, while those of late cultures contained glucanase II-2, predominantly.

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A bacterial strain No. 170, which was capable of producing penicillinase in alkaline culture conditions, was isolated from soil. The isolate No. 170 was identified to belong to the genus Bacillus. The cell growth and enzyme production of it were affected by the initial pH of the medium and by the carbon sources added; the best growth and maximum enzyme production were observed at pH 9.0. Among the carbon sources so far tested, glycerol and glucose were effective on the enzyme production at a concentration of 0.2_??_0.5% (w/v). The enzyme was inducible by penicillin and cephalosporin derivatives. The amount of enzyme produced reached maximum at 5 hr after induction by benzyl penicillin.
The optimal pH and temperature of penicillinase was between 6.0 and 7.0, and 50°C, respectively. The stable pH range of enzyme was comparatively broad, ranging about pH 7.0 to 10.0.

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Aldehydes were synthesized via α-acetoxy sulfides from alkyl aryl sulfoxides by the Pummerer reaction with acetic anhydride in the presence of base. By this method, isobutyraldehyde, pentanal, benzaldehyde, and 2-acetylamino-5-methylbenzaldehyde were obtained from isobutyl phenyl sulfoxide, pentyl p-tolyl sulfoxide, benzyl phenyl sulfoxide, and 2-acetylamino-5-methylbenzyl phenyl sulfoxide, respectively. The starting sulfoxides are easily synthesized from olefins, alkyl halides, or alkyl aryl sulfides.

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An yeast, Hansenula jadinii, which was one of the best producers of CDP-choline on our system, lost its activity when cultured in jar fermenter. This phenomenon was also reproduced in flasks. Cells cultured aerobically in the medium containing 1% of glucose (A-cells) could not phosphorylate nucleotides although development of mitochondria was observed, whereas cells cultured less aerobically in the medium containing 5% of glucose (D-cells) could phosphorylate CMP to CTP and finally produce CDP-choline although they had only poor mitochondria. Further study revealed that the A-cells were unstable in hexokinase activity, although they had the dense cytosol, whereas the D-cells remained stable, and they had many round particles. Glycolytic activity was about 4 times stronger in the D-cells than in the Acells. The phenomenon that respiration (development of mitochondria) suppressed fermentation (glycolysis) has been known as the Pasteur effect. However, in our system, phosphofructokinase, the primary key enzyme of the Pasteur effect, was active in the A-cells. Therefore, our phenomenon seemed to be a modified Pasteur effect.

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Damavaricin C, a degradative derivative of streptovaricin C, has a new active hydroxyl group at the C-19 position of the naphthoquinone moiety where various groups can be substituted by ether linkage. The biological activities of these ethers were compared against animal cells, including normal, virus transformed, and human cancer cells in vitro. Some of derivatives showed preferential lethal activity on virus transformed cells in vitro.

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The fate of nitrite in cured meat was investigated. Of added nitrite-N, 66_??_90% was found as nitrite, nitrate, nitrosothiol, denatured nitrosomyoglobin and gaseous nitrogen compounds, and the remainder of N was unidentified. The amount of unidentified N depended on both the curing period and the amount of added sodium ascorbate (AS).
Pork was separated into four fractions: dil. sodium chloride-soluble small-molecular fraction (Fr. 1), dil. sodium chloride-soluble large-molecular fraction (Fr. 2), Weber-Edsall solution-soluble fraction (Fr. 3) and Weber-Edsall solution-insoluble fraction (Fr. 4). Each fraction was cured and the fate of nitrite was examined. In the absence of AS, almost all nitrite-N was detectable, while in its presence, 73_??_82% of nitrite-N was detectable in both Fr. 1 and Fr. 2, 78_??_100% in Fr. 3 and 94_??_100% in Fr. 4. These results suggest that the unidentified nitrite-N in cured meat originated mostly from the reaction between the three meat fractions (Frs. 1, 2 and 3), nitrite and AS.

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Ultracentrifugically homogeneous glucomannan extracted from the bulbs of lily (Lilium maximowiczii Regel) was composed of β-(1→4)-linked D-glucose (1 part) and D-mannose (2 parts) residues and having a relatively small amount of branching point at C 3 of a β- (1→4)-linked D-mannose residue. Acetolysis of the polysaccharide led to the isolation of β- (1→4) -and β- (1→3) -linked oligosaccharides composed of D-mannose and/or D-glucose residues. The average chain length of the polysaccharide was determined by methylation analysis to be about 28.

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L-Methionine strongly inhibited the growth of Chromatium D when added at a low concentration to the growth medium containing both sulfide and thiosulfate. S-Adenosyl-L-methionine inhibited the growth, irrespective of the coexistence of sulfide and thiosulfate. Upon addition of L-methionine to the growth media, the presence of both sulfide and thiosulfate in the media stimulated the in vivo conversion of L-methionine to S-adenosyl-L-methionine, and consequently increased the intracellular level of S-adenosyl-L-methionine. From these data, it was strongly suggested that the unusual accumulation of S-adenosyl-L-methionine in the cells of Chromatium D is responsible for the growth inhibition by L-methionine.
The level of S-adenosyl-L-methionine synthetase (ATP: L-rnethionine S-adenosyltrans-ferase, EC 2. 5. 1. 6) was significantly enhanced by adding L-methionine, sulfide and thiosulfate to the growth medium.

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29-Hydroxy-3, 11-dimethyl-2-nonacosanone, one component of the sex pheromone of the German cockroach, was synthesized. The synthetic compound was equivalent in the biological activity for the male to raise his wings to the natural one and was much more active than 3, 11-dimethyl-2-nonacosanone which was another component of the pheromone.

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Methylcitrate condensing enzyme functioning at the entrance to the methylcitrie acid cycle was purified 70-fold from cell-free extracts of Candida lipolytica. The purified enzyme preparation catalyzed the liberation of CoASH strongly from propionyl- and acetyl-CoA derivatives and weakly from butyryl- and valeryl-CoA derivatives in the presence of oxaloacetate. The enzyme, however, was specific for oxaloacetate and did not catalyze the liberation of CoASH from acetyl- or propionyl-CoA in the presence of glyoxylate, pyruvate or α-ketoglutarate.
All the properties of this preparation were compatible with the conclusion that the sole enzyme, here referred to as methylcitrate synthase, can catalyze the condensation of oxaloacetate not only with propionyl-CoA but also with acetyl-CoA and that this synthase clearly differs from si- and re-citrate synthases.
The powerful inhibition of methylcitrate synthase by ATP, NADH and NADPH supports the idea that the physiological role of the methylcitric acid cycle is a catabolic reaction sequence concerning the oxidation of propionate into pyruvate and that this synthase is a regulatory enzyme of this cycle.

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Free ceramides isolated from A. oryzae were fractionationed into three groups by thinlayer chromatography on silica gel G according to degree of hydroxylation of the molecules. Each group was converted to trimethylsilyl ether derivatives, which were analyzed by gas-liquid chromatography-mass spectrometry for the structure of the molecular species. As a result, the representative molecular species of ceramides were characterized as N-lignoceroyl-phytosphingosine (1%), N-2-hydroxylignoceroyl-phytosphingosine (31%) and N-2, 3-dihydroxylignoceroyl-phytosphingosine (31%).

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To develop a practical method for production of L-α-methyl DOPA, the optical resolution of its precursor, DL-3- (3, 4-methylenedioxyphenyl) -2-methylalanine, was studied. The monohydrochloride of DL-3- (3, 4-methylenedioxyphenyl) -2-methylalanine was resolved by a preferential crystallization procedure. Optically pure L-α-methyl DOPA was obtained in good yield. Industrial production of L-α-methyl DOPA by the present simple method is considered to be very promising.

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