Feeding rats with either a carbohydrate meal or a fat meal to the previously fasted rats caused significant decrease in urinary output of urea and total nitrogen. The content of free leucine in skeletal muscle decreased in the rats fed either a carbohydrate meal or a fat meal. Feeding of either a carbohydrate meal or a fat meal stimulated incorporation of L-leucine-1-¹⁴C into protein fraction of skeletal muscle and reduced its oxidation to ¹⁴CO₂.
These results suggest that the metabolism of leucine is under nutritional regulation and that the decrease in content of free leucine in skeletal muscle might be caused by enhanced reutilization of leucine into protein by the feeding of a carbohydrate meal or a fat meal. The role of free leucine in skeletal muscle as a regulator of protein turnover in the tissue are discussed in relation to the metabolism of this branched chain amino acid.

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Cellulase was produced by Trichoderma viride in semisolid cultures of rice bran, rice straw and rice hulls. T. viride QM 9414 generally produced higher cellulolytic activity on CM-cellulose (C_x activity) using rice bran-rice hull mixture (2:1 w/w) as substrate compared to strains ITCC 1433 and D 4014. It showed higher C_x activity on rice bran-rice straw mixtures than on rice bran-rice hull mixtures. Maximal extraction of the enzyme from mold bran was obtained with 0.05M sodium citrate buffer, pH 3.5.

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When mice were immunized with adequate doses (1.0_??_5.0mg) of tumor cells attenuated with acetone-ether, complete resistance to the graft of Sarcoma 180 could be induced. The serum taken from mice immunized with repeated challenges was found to display immune adherence reactivity and the antibody titer of anti-Sarcoma 180 serum was higher than that of anti-sarcoma 37 or anti-Ehrlich serum prepared from respective tumor resistant mice.
The interaction between anti-Sarcoma 180 serum and various lines of tumor cells was investigated by the tests of immune adherence absorption and cytotoxicity.
Sarcoma 37 cells exhibited the same reactivity as Sarcoma 180 cells in both tests. Ehrlich cells showed lower reactivity than Sarcoma 180 or Sarcoma 37. Neither MH 134 cells nor myeloma cells exhibited a detectable reactivity in the test of cytotoxicity in vitro. On the other hand, in the test of cytotoxicity in vivo, MH 134 was slightly inhibited and myeloma was promoted in tumor growth.
These results suggest that anti-Sarcoma 180 serum prepared in this experimental system might be useful for the classification of tumor cells and in the study of tumor surface.

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Among mouse antibodies against Sarcoma 180, immune adherence activity was found only in IgM fraction and cytotoxicity was recognized in fractions both IgM and IgG. Hyperimmunization of mouse with Sarcoma 180 cells increased the cytotoxicity in some fractions of IgG and also brought about an appearance of a new protein (protein T) with immune adherence activity. A molecular weight of the new protein as estimated by gel filtration was approximately 240, 000.
On reduction and carboxymethylation, cytotoxic activity of IgM and immune adherence activity of IgG disappeared completely. Contrary to this, considerable retentions of cytotoxicity of IgG and immune adherence activity of IgM were observed.

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Cells of Escherichia coli at the logarithmic phase of growth lost colony-forming ability when treated in 0.01M Tris buffer containing 0.15M sodium chloride and then diluted with 0.01M Tris buffer. The sodium chloride-treated cells did not lose colony-forming ability when they were diluted with 0.01M Tris buffer containing 0.15M sodium chloride. Furthermore, when the concentration of Tris buffer for dilution was raised to 0.15M, the decrease in survival was effectively prevented. Lysis of sodium chloride-treated cells was observed during incubation in 0.01M Tris buffer. This cell lysis was inhibited by the presence of Mg²⁺, Ca²⁺ or Mn²⁺ in the dilution buffer and also by incubation at 0°C. The cell lysis seemed to be unrelated to the loss of viability, since viability decreased rapidly when the sodium chloride-treated cells were diluted with 0.01M Tris buffer at 0°C, where the cell lysis was not observed. A polymyxin B resistant mutant was more sensitive to sodium chloride treatment but was more resistant to sucrose-osmotic shock than its parent strain. These results suggest that the saline sensitive phenomenon involves osmotic shock of the sodium chloride-treated cells. Thus, we called this phenomenon sodium chloride-osmotic shock.

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The degradation of RNA was induced during incubation of Escherichia coli cells in 0.01M Tris buffer containing 0.15M sodium chloride (0.15M NaCl-Tris buffer). After incubation in 0.15M NaCl-Tris buffer for 120min, approximately 50% of RNA was lost from the acid insoluble fraction. When magnesium (50mM) was added to 0.15M NaCl-Tris buffer, the degradation of RNA was completely prevented. When crude ribosomes, which were prepared by sonic disruption of the cells, were incubated in 0.15M NaCl-Tris buffer, RNA was rapidly degraded but the addition of magnesium (5mM) again prevented the degradation of RNA. 3'-Mononucleotides, but not 5'-mononucleotides, were determined as the main degradation products of cellular RNA. When E. coli Q 13, a mutant deficient in ribonuclease (RNase) I, was treated in a similar fashion, no degradation of RNA occurred. These results suggest that the degradation of RNA during incubation in 0.15M NaCl-Tris buffer is due to the enzymatic action of RNase I.

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Polyethylene adipate (PEA)-degrading enzyme of Penicillium sp. strain 14-3 was purified by precipitation with ammonium sulfate and chromatography with CM-Sephadex C-50. The purified enzyme was confirmed to be homogeneous by ultracentrifugal analysis and polyacrylamide gel electrophoresis. Some properties of the purified enzyme were examined. The molecular weight of the enzyme was estimated by gel filtration on Sephadex G-100 to be approximately 25, 000. Optimum pH and temperature were around 4.5 and 45°C, respectively. The enzyme was stable up to 50°C and in a pH range from 4.0 to 10.0 on 5.5 hr incubation at 35°C. The enzyme was activated remarkably by Ca²⁺ and Cd²⁺. In substrate specificity, this enzyme degraded various kinds of saturated and unsaturated aliphatic polyesters and polycyclohexanedimethanol adipate as alicyclic polyester but not aromatic polyesters such as polytetramethylene terephthalate, polyethylene tetrachrolophthalate and poly-2, 2-dimethyl-trimethylene isophthalate. Bisphenol A polycarbonate, a polycarbonate resin, was also degraded. Polyesters with a few hybrid bonds among polymer chains were hardly degraded. A kind of terminal groups, such as hydroxy, hexahydrophthalic acid^* and hexahydrophthalic acid glycidil ester^** terminal did not affect so much on the enzyme activity. The enzyme further hydrolyzed various plant oils, triglycerides and methyl esters of fatty acid. Therefore PEA-degrading enzyme was assumed to be a kind of lipase.

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Comparative studies on the activities of isocitrate lyase and malate synthase were performed in the cells of Candida yeasts grown on media containing glucose, n-alkane or acetate as the sole carbon source. In general, the activities of both enzymes were higher in the cells growing on n-alkane or acetate than in those growing on glucose. When the yeasts were cultivated on glucose, the level of the isocitrate lyase activity in C. tropicalis was enhanced after the middle phase of growth, while the activity in C. lipolytica was maintained at a low level. The synthesis of isocitrate lyase in C. tropicalis growing on n-alkane or acetate was repressed by the addition of glucose to the medium, and derepressed when the cells grown on glucose were transferred to n-alkane or acetate media, indicating that glyoxylate cycle has an important role in the metabolism of n-alkane as well as acetate. Cycloheximide inhibited the synthesis of isocitrate lyase in C. tropicalis growing on n-alkane or on acetate.

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The level of isocitrate lyase, an enzyme of glyoxylate cycle, in Candida tropicalis was enhanced at the later period of growth when the yeast was cultivated in a semisynthetic glucose medium. On the other hand, such increase in the enzyme activity was not observed in C. lipolytica grown under the same conditions. In the case of C. tropicalis, high concentrations of glucose remaining in the medium permitted the increase in the enzyme activity and the addition of ethanol, one of the major products from glucose, to the glucose medium did not stimulate the enzyme formation, indicating that the enhanced enzyme level in the yeast was not merely attributable to the release from the repression by glucose or to the induction by ethanol. Biotin, one of the growth-stimulating factors for C. tropicalis, affected markedly the level of isocitrate lyase. That is, the supplementation of biotin to the synthetic glucose medium inhibited completely the increase in the enzyme activity, and reversely the absence of biotin stimulated the enzyme formation in the glucose-assimilating cells. Thiamine, another growth-stimulating factor for C. tropicalis, did not show any effect on the level of isocitrate lyase in the yeast. The level of isocitrate lyase in C. lipolytica growing on glucose was not affected by biotin added exogenously.

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A bacterium KY 3071 that was found to produce a new aminonucleoside antibiotics, 2'-amino-2'-deoxyguanosine (2 AG), was identified as Enterobacter cloacae KY 3071.
Amount of dipotassium phosphate and ammonium sulfate affected 2 AG production greatly and their concentration must be 0.2 and 15g/liter for the efficient 2 AG production, respectively.
Addition of purine nucleotides promoted 2 AG production, particularly xanthosine-5'-monophosphate was most effective, and purine nucleosides, on the contrary, inhibited the 2 AG production. The maximum amounts of 2 AG were approximately 0.4g/liter after 24 hr of incubation.

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Blood-coagulating protease produced extracellularly by Cephalosporium sp. was purified. The purified enzyme moved homogeneously with a sedimentation constant, S_{20, W} of 2.90 s by ultracentrifugation and gave a single protein band on the polyacrylamide gel electrophoresis. The enzyme was an EDTA-sensitive alkaline protease and Ca²⁺ stabilized its activity. Molecular weight of the enzyme was estimated as 39, 000 by Svedberg's method and 124, 000 by Andrews' method. The enzyme was considered to activate Factor X to Xa. The specific blood-coagulating activity of the enzyme was 1/5 of that of bovine thrombin.

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Approximately five tyrosine residues of ricin D were iodinated preferentially under appropriate conditions probably forming diiodotyrosine. Iodination of this toxin carried out in 0.1M phosphate buffer at pH 7.0 and 0°C for 60min with a 20 fold molar excess of iodine per mole of protein, yielded a main component which appeared as a single band on polyacrylamide gel disc electrophoresis. Analysis of protein-bound radioactivity and the content of diiodotyrosine of ¹³¹I-labeled ricin D revealed that two tyrosine residues in the isoleucyl chain and three in the alanyl chain were substituted. The toxicity of iodinated ricin D decreased to one hundredth of that of native protein. However, the hemagglutinating activity of this protein was not affected by the iodination reaction.

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The content of ribosomes was high at the initial stage of the pupa of Bombyx mori, but it declined to a minimum level at the mid-pupal stage. The activities of isolated ribosomes to incorporate amino acids into protein showed a similar variation to that of the ribosome content. The bulk RNA extracted from the pupae at the middle stage showed heterogeneous fractions when analyzed by sucrose density gradient centrifugation. During the latter half of the pupal period, the ribosome content increased and the isolated ribosomes again showed high activities to incorporate amino acids. These facts indicate that changes in nature as well as in content of ribosomes may play important roles in the control of protein synthesis during adult development of Bombyx mori.

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The cobalt-resistant mutant (resistant up to 1000 μg Co/ml) was obtained from E. coli B-ATCC 11246 by means of incubating the parent cells in the media which contains cobalt. The mutant produced by this way is resistant only to cobalt, but not to other metals such as Mg²⁺, Ca²⁺, Cr³⁺, Cr₂O₇^2-, Mn²⁺, Fe²⁺, Fe³⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺ and Hg²⁺, and specifically suppresses Co²⁺ uptake. The difference in membrane proteins between the parent and resistant cells is observed. The granules densely stained are appeared in the parent cells incubated with Co²⁺ under the image of electron microscope.

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A ferrocytochrome c: hydrogen-peroxide oxidoreductase (EC 1. 11. 1. 5) was purified from the obligate chemoautotroph Thiobacillus thiooxidans. The purified enzyme had protoheme as the prosthetic group and its absorption maxima were 397, 489 and 635 nm in oxidized form, while 422 and 560 nm in reduced form. The molecular weight and the sedimentation coefficient were estimated to be 32, 000 and 2.7 S, respectively. The enzyme utilized ferrocytochrome c and NADH as an electron donor. Both peroxidizing activities toward cytochrome c of T. thiooxidans and that of horse heart were almost the same level. The activity of ferrocytochrome c peroxidation increased in almost parallel with that of NADH peroxidation in the course of purification of the enzyme. Both enzyme activities were highly stable at pH 7.0 against heating. The ferrocytochrome c peroxidizing activity was inhibited completely with 1mM cyanide and about 60% with 1mM azide. Although ten-fold higher concentration of inhibitors was required, NADH peroxidizing activity was also inhibited with cyanide and azide. Both peroxidizing activities were inhibited about 60% with CO.

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A soil microorganism which was capable of growing in a medium containing baker's yeast cells as a carbon source was isolated and identified as Acinetobacter sp. When grown in a medium containing baker's yeast cells, the organism secreted β-1, 6-glucanase, β-1, 3-glucanase and α-mannosidase into the culture medium. Several peaks showing α-mannosidase activity appeared in DEAE-Sephadex A-50 column chromatography. One of α-mannosidase components showing the highest activity was purified 34-fold over the culture fluid. The enzyme was active on Saccharomyces cerevisiae mannan and some of oligosaccharides produced by the acetolysis of yeast mannan. From the action patterns against these carbohydrates, conclusion being reached, the enzyme is α-1, 2-mannosidase spliting α-1, 2-mannosyl linkage from nonreducing end.

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Creatinine deiminase (EC 3. 5. 4. 21) was formed in large quantities in the cells of Corynebacterium lilium ATCC 15990, aerobically grown on creatinine as a sole source of nitrogen. The creatinine deiminase was purified and crystallized from the cell extracts by a procedure involving fractionation with ammonium sulfate, treatment with protamine, and chromatographies on DEAE-cellulose, Sephadex G-100, and hydroxylapatite. This process resulted in a 2400-fold increase in specific activity with a recovery of 9.1%. The crystalline enzyme was homogeneous on acrylamide gel electrophoresis and ultracentrifugation (s_{20, W}=10.44S).

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The investigation was carried out in order to elucidate the reason for the reduction in nutritive value of browned protein, by using labeled casein as a model protein. Goat casein preparation in which lysine residues had been labeled with ¹⁴C was browned by amino-carbonyl reaction with glucose at 37°C. Browned or non-browned casein was ingested by growing rats by spaced feeding.
When the rats ingested the browned casein the experimental group, higher radioactivity was found in TCA-soluble fraction in the small intestine as compared with that in the control group, while radioactivity was scarecely found in feces for 22 hr. Along with absorption delay, considerably high radioactivity was found in urine. The recovery of radioactivity in expired air of rats fed the labeled casein (browned and non-browned) was measured. In the experimental group, expired ¹⁴CO₂ came out slower than the control group. From these results, it is suggested that the main reason for the reduction in nutritive value by browning reaction may be the formation of a lysine derivative in a protein, which remains in the small intestinal lumen as an absorption-delayed material and is finally excreted in urine.

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Similarities and dissimilarities of amino acid sequences among the acidic subunits were analyzed by quantitative immunological precipitin with antibodies to the subunits, gel filtration of the CNBr-fragments and ion exchange chromatography of the tryptic peptides.
The gel chromatograms of the CNBr-fragments and the ion exchange chromatograms of the tryptic peptides of A₁ and A₂ subunits have demonstrated that they are two distinct polypeptide subunits which have very similar primary structures. Quantitative immunological precipitin revealed that A₁, A₂ and A₃ subunits were strongly immunologically related, therefore indicated that they shared a considerable degree of sequence homology. In fact, the analyses of the tryptic peptides of A₁, A₂ and A₃ subunits showed the sequence homology among the three subunits. Although A₄ subunit was shown to be serologically distinct polypeptide subunits from the other three subunits, some similarities of amino acid sequences were observed by the analyses of the tryptic peptides.

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Three new substituted cinnamoyl hydroxycitric acids have been isolated from corn plant (Zea mays L.) and their structures established as 2-O-trans-p-coumaroyl-(2S, 3S)-hydroxy-citric acid (I), 2-O-trans-feruloyl-(2S, 3S)-hydroxycitric acid (II), and 2-O-trans-caffeoyl-(2S, 3S)-hydroxycitric acid (III) on the basis of spectroscopic and chemical evidence.

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The racemic, (+)- and (-)-forms of cyanofenphos (O-p-cyanophenyl O-ethyl phenyl-phosphonothioate) were rapidly metabolized in the rat by cleavage of P-O-aryl linkage, cleavage of P-O-alkyl linkage and conjugation of p-cyanophenol with sulfuric acid. There was a marked difference in the proportion of the major urinary metabolites, p-cyanophenol and p-cyanophenyl sulfate, with three forms of cyanofenphos.
The three forms of cyanofenphos were metabolized at almost equal rates in rat liver microsomes-NADPH system. (+)-Cyanofenphos underwent oxidation of P=S to P=O and cleavage of P-O-aryl linkage predominantly. In contrast, the (-)-isomer was converted to the corresponding oxon analog by mixed function oxidase, and then the oxon analog was rapidly hydrolyzed to p-cyanophenol by microsomal arylesterase-type enzyme, This microsomal enzyme had a remarkable selectivity in hydrolyzing (-)-cyanofenphos axon versus the (+)-isomer. Stereoselectivity in the metabolism of the cyanofenphos isomers in the rat appears likely to be mainly due to selective hydrolysis of the (-)-oxon analog by the arylesterase-type enzyme.

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Smoke condensates of lamina and midrib cigarettes of flue-cured tobacco leaves were subjected to glass capillary column gas chromatography without fractionation. A flame thermionic detector (FTD), which is specific for N-containing organic compounds, was used. By this method, pyridines, pyrroles and lactams were determined simultaneously. Nicotine was a major component, in both smokes. In regard to the other components, degradation products of nicotine predominated in lamina smoke, while pyrazines and oxygenated N-compounds predominated in midrib smoke. In this study, several N-containing compounds were found for the first time in tobacco smoke.

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∅X174 DNA synthesis as well as phage production was inhibited by rifampicin when added in early phase of infection. Rifampicin did not inhibit the formation of parental duplex replicative-form, RF, and it inhibited the synthesis of progeny RF under conditions where protein synthesis was not necessary to be synthesized continuously. In addition, replication of parental RF into progeny RE was inhibited by rifampicin under conditions where a high concentration of chloramphenicol did not affect the replication. Consequently, it could be concluded that RNA synthesis other than that required for protein synthesis was necessary for both the initiation and continuation of RF replication.

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After a eleven-steps purification, a peptidyl factor named α substance-I_A was isolated in pure form from a culture filtrate of α type cells of the heterothallic Saccharomyces cerevisiae. The substance induced the sexual agglutinability in a haploid cells belonging to the opposite mating type at concentrations from 0.4 to 0.8 ng/ml.

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A peptidyl factor named α substance-I_A, which induces sexual agglutinability in α type cells of the heterothallic Saccharomyces cerevisiae, was found to be composed of twelve amino acid residues. Further, the amino acid sequence was elucidated by the combined application of the Edman-dansyl procedure and the cleavage reaction with cyanogen bromide to be H-His-Trp-Leu-Gln-Leu-Lys-Pro-Gly-Gln-Pro-Met-Tyr-OH.

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