α-Glucan produced by crude dextransucrase (CEP) of Streptococcus mutans E49 was separated into the following three fractions: a water-insoluble glucan fraction (designated as IG), a water-soluble glucan fraction with a wide distribution of molecular weight (SG-1) and an oligosaccharide (SG-2). Formation of these products, which had characteristic courses, were remarkably reduced in the presence of ribocitrin. Production of IG and SG-1 by CEP and the inhibitory activity of ribocitrin were highly pH-dependent. With regard to dextran T10, ribocitrin inhibited IG production competitively.

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Enzymes participating in glucan synthesis by Streptococcus mutans E49 were separated into two fractions with distinctly different activities by chromatography on DEAE Bio-Gel A. The insoluble glucan (IG) was revealed to be formed by the coupling reaction of these two enzymes, dextransucrase (SGE), which synthesizes soluble glucan from sucrose, and a glucan insolubilizing enzyme (IGE), which forms IG from soluble glucan.
Ribocitrin was found to inhibit IG synthesis by inhibiting SGE.

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A new dye-linked alcohol dehydrogenase (vanillyl alcohol dehydrogenase) was purified to homogeneity from cells of Rhodopseudomonas acidophila strain M402 grown aerobically on vanillyl alcohol. The reaction product from vanillyl alcohol was identified as vanillin as judged by its melting point, elemental analysis and IR, mass and NMR spectra. The molecular weight of the enzyme was estimated to be approximately 72, 000 as determined by gel filtration and the isoelectric point was pH 6.01.
The most characteristic feature of this enzyme is its wide substrate specificity range. The enzyme catalyzes the dehydrogenation of various aromatic and aliphatic alcohols and aldehydes with phenazine methosulfate as electron acceptor. The active substrates of this enzyme are as follows: Vanillyl alcohol, benzyl alcohol, cinnamyl alcohol, 2-phenylethanol, 2-phenoxyethanol, aliphatic alcohols of C₂ to G₈, trans-cinnamaldehyde, formaldehyde, propionaldehyde and butyraldehyde. The highest activities were obtained with vanillyl alcohol, n-propanol and n-butanol at the same level. The apparent Km values were as follows: 112μm for vanillyl alcohol, 7μm for benzyl alcohol, 180μm for n-propanol, 14μm for n-butanol, 20μm for 2-phenoxyethanol, 12μM for 2-phenylethanol and 105μm for butyraldehyde. These activities were confirmed to be catalyzed by a single enzyme by activity staining on polyacrylamide gels. But the enzyme is completely inert on vanillin and methanol.
Therefore, dye-linked alcohol dehydrogenase is the most suitable name for this enzyme from R. acidophila M402 rather than vanillyl alcohol dehydrogenase or aromatic alcohol dehydrogenase, but this enzyme is substantially different from the dye-linked alcohol dehydrogenase from R. acidophila 10050 which is active on methanol.

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A large amount of anthocyanin was accumulated in the callus tissues of Vitis hybrids without light irradiation.
Culture conditions for the production of anthocyanins by Vitis cells in suspension cultures were investigated. High sucrose and low phosphate concentrations brought about a marked increase of anthocyanin formation, while high concentrations of nitrate, phosphate, and 2, 4-D repressed the pigment formation. The effects of these nutrients depended on the concentrations of coexistent ones.
Regulation of the aeration rate was important for anthocyanin formation in submerged aerated cultures and light irradiation enhanced anthocyanin formation in cultured cells.

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An α-amylase which produces both maltotetraose and maltopentaose from starch as the main products was found in the culture filtrate of a strain of Bacillus circulans which was newly isolated from soil. The enzymewas purified to be almost homogeneouson disc electrophoresis in polyacrylamide gel by means of ammoniumsulfate fractionation, DEAE-Sepharose column chromatography and Sephadex G-200 gel filtration.
The optimum pH and temperature of the enzymewere around pH 7.0 and around 50°C, respectively. Metal ions such as Hg²⁺, Cu²⁺, Ni²⁺, Zn²⁺, Fe²⁺ and Co²⁺ strongly inhibited the enzyme activity. The molecular weight was about 45, 000. The yields of maltotetraose and maltopentaose from potato starch were 30-40% and 20-30%, respectively.

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The amount of extra- and intravascular albumin was estimated in two groups of rats, i. e., those fed a 20% casein (20% protein) diet and a 3% casein (low protein or 3% protein) diet.
The fractional turnover rate of whole body plasma albumin was also measured in the two groups of rats, employing the constant infusion method of Waterlow et al. At the same time, the fractional turnover rate of the whole body protein was measured.
When the diet was changed from the 20% protein to the 3% protein diet, the amount of albumin mass in both extra- and intravascular spaces decreased significantly. During 7 days on the diet, the extra- and intravascular albumin mass per 100g of body weight did not change significantly in the rats fed the 20% protein diet. On the other hand, rats fed the 3% protein diet lost almost 30%of the extra- and intravascular albumin per 100g body weight.
The fractional turnover rates of whole body albumin were estimated to be 31.7 and 19.8%/day in the 20% protein and the 3% protein diet-fed rats, respectively. The fractional turnover rates of whole body protein were 16.1 and 10.6%/day in the 20% protein and the 3% protein diet-fed rats, respectively.
The leucine fluxes to albumin synthesis and whole body protein synthesis were calculated to be 5.9 and 83μmol/hr, respectively, in the 20% protein diet-fed rats. The leucine fluxes in the 3% protein diet-fed rats were 2.5 and 54μmol/hr for the albumin synthesis and for the whole body protein synthesis, respectively.
These results demonstrate the quantitative significance of albumin metabolism in the whole body protein turnover in rats fed on two levels of protein intake.

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The action of Thermoactinomyces vulgaris α-amylase was examined in order to elucidate whether this α-amylase catalyzes the hydrolysis of α-1, 4- and α-1, 6-glucosidic linkages in some oligosaccharides at the same catalytic site. The optimum pH for its action on maltotriose and isopanose (α-D-Glcp-(1→4)-α-D-Glcp-(1→6)-D-Glcp) was 4.5, which was the same as the value for starch and pullulan. Hydrolysis patterns of isopanose by this α-amylase were dependent on the substrate concentration. At a low substrate concentration (0.5%) equimolar maltose and glucose were produced from isopanose. At a high substrate concentration (4.0%) a small amount of isomaltose was found besides maltose and glucose, while the molar ratio of glucose to maltose plus isomaltose was unity at the early reaction stages. Hydrolysis patterns of reducing end-(¹⁴C)-labeled maltotriose was also dependent on substrate concentration. Increasing the substrate concentration from 0.5 to 4.0%, the molar ratio of labeled glucose to labeled maltose in the products was decreased from 6 to 1.5. Apparent formation of labeled glucose was depressed by the addition of isopanose to the labeled maltotriose-hydrolyzing mixture. The results above supported the view that this enzyme can hydrolyze α-1, 6-glucosidic linkage as well as α-1, 4-glucosidic linkage in isopanose or maltotriose at the same site.

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The flow properties of soybean protein-lipid-water suspension systems and coagulated gels were related to a protein-lipid interaction. For powdered soybean lecithin-added soybean protein suspension systems and their heat-induced gels, the yield stress (σ_y) and the consistency index (K) increased with increasing amounts of added lipid, but the flow behavior index (n) and the thixotropy index (TI) decreased. On the other hand, there were only small changes in the magnitudes of the thixotropic parameters and the viscometric parameters (σ_y, K and n) after adding soybean oil at various concentrations to soybean protein dispersions. These facts suggested that the formation of a protein-phospholipid complex increased the effective particle size, and that the intermolecular entanglements and linkages among the protein molecules or among the proteinphospholipid complexes were weakened by the addition of polar lipids. The thixotropy index defined in this study is available for characterizing the stress decay that occurs within soybean protein dispersions and heat-induced gels as they are sheared.

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A neutral and an acidic arabinoxylan fraction (H-1 and H-2) were obtained from rice endosperm cell wall. The results of methylation analysis and partial hydrolysis of these fractions showed that both of them have highly branched structures in which approximately 6 out of 7 (H-1) and 5 out of 6 (H-2) of the (1→4)-linked D-xylose residues are branched. Most of the side chains in H-1 consists of single α-L-arabinofuranose residues, whereas some of them in H-2 were substituted with α-D-glucuronic acid or 4-O-methyl-α-D-glucuronic acid residues, both attached to the O-2 position of D-xylose residues. These highly branched arabinoxylans are not readily hydrolyzed by an endoxylanase of Streptomyces sp.

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The structures of two new anticoccidial antibiotics, WS-5995A and B, produced by Streptomyces auranticolor, were determined as I and II, respectively, on the basis of spectral and chemical evidence.
WS-5995 A (I), having 5H-benzo[d]naphtho[2, 3-b]pyran as its mother skeleton, was synthesized by coupling the diazonium salt prepared from the anthranilic acid (IX) to 3-hydroxy juglone (VIII).

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A transformant (HS-29) which produced a considerable amount of extracellular protein (7.2mg/ml) was isolated from Bacillus mesentericus niger No. 6021 that produced RNA extracellularly. When 1.5% glycine was added to the medium as an excretion stimulator, the maximum yield of extracellular protein amounted to 1O mg per ml of the culture after 7 days. Exoprotein produced by strain HS-29 gave a somewhat different gel pattern with or without glycine on SDS polyacrylamide gel electrophoresis.
Protease production by strain HS-29 was repressed by adding glycine to the medium.
Therefore, glycine might stimulate protein excretion as well as protect the excreted protein from protease.

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The autoxidative stability of triglyceride molecular species was analyzed by determining the residual molecular species after incubating synthesized triglycerides (TGs), interesterified TGs and soybean oil TGs, respectively. The autoxidative stability of each molecular species of TG depends on the degree of unsaturation of TGs and the length of the saturated acyl chain present in glycerides. Thirteen types of soybean oil TG molecular species were isolated by high performance liquid chromatography. Among them, the TG groups most resistant to autoxidation were 2-oleoyl-1( 3)-stearoyl-3(1)-palmitin, 1, 3-dipalmitoyl-2-olein, 2-oleoyl-1(3)-oleoyl-3(1)-stearin and 2-oleoyl- 1(3)-oleoyl-3(1)-palmitin.

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The influence of the positions of unsaturated acyl groups in the glycerides on autoxidation was analyzed in relation to synthesized and soybean oil triglycerides. No discrepancies in rates of autoxidation of unsaturated acyl groups at different positions in the glycerides (between PLP and PPL, between PLnP and PPLn) was observed. Likewise, no discrepancies were observed before or after interesterification of synthesized triglyceride mixtures or soybean oil triglyceride. In the case of trilinolein, peroxidation occurred at random at both the α- and β-positions. (P, palmitic acid; L, linoleic acid; Ln, linolenic acid.)

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The distribution of ω-ammo acid transaminases in microorganisms was investigated. ω-Amino acid : pyruvate t ansaminase (ω-APT) was found bacteria and yeasts, but not in actinomycetes and fungi. On the contrary, aminobutyrate : α-ketoglutarate transaminase (GABA-T) was shown in most of the microorganisms from bacteria to fungi. β-Alanine is a preferred amino donor for the ω-APT reaction. Although bacterial and yeast GABA-T are inactive for β-alanine, fungal and actinomycete enzymes react with this compound and γ-aminobutyrate. In comparing these results with those of plant and mammalian enzymes, two different pathways of ω-amino acid metabolism are suggested for bacteria, yeast and plants, i.e. one for β-alanine and the other for γ-aminobutyrate, catalyzed by ω-APT and GABA-T, respectively. In actinomycetes, fungi, and mammals GABA-T may be involved in the metabolism of both ω-amino acids. In addition, evolutionary changes of ω-amino acid transaminases are discussed.

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Protein components from eight lines of winged bean (Psophocarpus tetragonolobus) seeds which were originally introduced from Papua New Guinea, Indonesia, Nigeria, and Ishigaki, and cultivated in Okinawa and Fukuoka, were investigated. Two major peaks which had sedimentation coefficients, s₂₀, of about 2.5S and about 6.5S (6.0 to 6.6 for the 8 lines), and no larger component were observed in all specimens with more than 90% extraction. Electrophoretic profiles of the "6.5S" component(s) which was separated with Sepharose 6B column chromatography showed a main broad band and a few minor bands which seemed to be essentially similar among the eight lines of winged bean. Thus the "6.5S" protein surely could be regarded as the common storage protein in winged bean seeds. The subunit structure of the "6.5S" component(s) in SDS solution consisted of four major bands. The "2.5S" components were mixtures and combinations of various proteins which were distinctly different from one selection to another.

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Conditions were defined which extract more than 90% of winged bean (Psophocarpus tetragonolobus) seed proteins. Sedimentation profiles of whole seed extract from winged bean, soybean, and common bean (variety "Kintokimame") at various pHs and ionic strengths were compared, because winged bean and soybean are resemble each other closely in their protein- and lipid-rich nature, and winged bean and common bean (Phaseolus vulgaris) are thought to be of nearly related families. However, a clear dissimilarity of their "6 to 7S" component(s), one of the main storage proteins in the three beans, was represented. Two main peaks of winged bean protein by Sepharose 6B chromatography were shown to correspond to the "6.5S" and "2.5S" components. Extrapolated s_{20, w}, or s⁰_{20, w} of the "6.5S" component seemed to have no practical meaning because the actual structure of the "6.5S" protein distilled water or very low ionic concentrations were altered discontinuously from the usual patterns. Further purification of the "6.5S" component(s) could be carried out by rechromatography on Sepharose 6B or DEAE Sepharose, eliminating minor components. However, the electrophoretic or ultracentrifugal patterns showed the occurrence of small amounts of aggregation simultaneously. The structure of the "6.5S" component was preserved for several months by freezing.

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In order to examine the applicability of the exhaust gas components from the tobacco-roasting process as cigarette flavor ingredients, a preliminary study on the composition of the semivolatiles included in the volatiles from roasted tobacco was conducted. A relatively large quantity of sugar pyrolysates (furans, volatile ketones and lactones) in addition to lower fatty acids and the components of essential oils were found in the condensate of the volatiles from roasted flue-cured tobacco. The condensate from roasted burley tobacco contained nicotine and neophytadiene as major components, and a number of other components of essential oils were also found. The above mentioned compounds in the condensate from flue-cured tobacco were assumed to contribute to its burnt-sugar like aroma. A sweet note of the condensate from burley tobacco might be attributable to the high concentration of the components of essential oils.

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The activity of alcohol acetyltransferase, bound to the cell membrane and responsible for the formation of acetate esters, was affected by the fatty acid composition of the cell membrane. When saturated fatty acids, which only slightly inhibit alcohol acetyltransferase activity, were incorporated into the cell membrane, the enzyme activity and ester formation were only slightly affected. On. the other hand, when unsaturated fatty acids, which strongly inhibit the enzyme activity, accumulated in the cell membrane, ester formation was suppressed with inhibition of the enzyme activity. The mechanism of formation of acetate esters by brewers' yeast was explained by the alcohol acetyltransferase activity under the influence of the fatty acid composition of the cell membrane.

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Anthranilate phosphoribosyltransferase (PRT), the second-step enzyme in the tryptophan specific biosynthetic pathway of Brevibacterium flavum, was inhibited by L-tryptophan but not by D-tryptophan, L-phenylalanine or L-tyrosine at all. The pattern of the inhibition by various tryptophan analogs was quite different from that of anthranilate synthase (AS), the first-step enzyme in the pathway. The concentration of trytophan giving 50% inhibition of PRT and the inhibitor constant for tryptophan, Ki, were 0.15 and 0.26mM, respectively. The inhibition of PRT was noncompetitive for both the substrates, anthranilate and phosphoribosylpyrophosphate. Gycerol increased the sensitivity to the tryptophan inhibition as well as the activity, whereas KCl and NaCl stimulated the PRT activity alone. In all the mutants tested, the feedback inhibition of PRT was removed concomitantly with that of AS. When phenylalanine tyrosine double auxotrophs having derepressed levels of the tryptophan enzymes were cultured under tyrosine-limitation, they accumulated anthranilate but not tryptophan, as did those having normal repression control. These results were concluded to be due to the presence of the feedback inhibition by tryptophan of PRT. In Bacillus subtilis K, the inhibition by tryptophan of PRT was much weaker than that in B. flavum and almost the same as that in B. flavum mutants having PRT resistant to the feedback inhibition. PRT in a tryptophan-producing mutant of B. subtilis wassimilar to the wild-type enzyme.

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Five kinds of pyridine derivatives (1-5), including a novel compound, 5-phenyl-2- propylpyridine (4), were newly identified in peppermint oil.

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The gene for β-isopropylmalate dehydrogenase of Clostridium butyricum M588 has been cloned in E. coli. The genome of Clostridium butyricum M588 was digested with restriction endonuclease EcoRI and joined to plasmid pBR322. Competent E. coli HB101 cells were transformed with the hybrid plasmids and the leucine⁺ transformants were selected. The plasmid, pCE4, containing four EcoRI fragments, was isolated from the transformants. It was found that the 2.2kb EcoRI fragment on a reconstructed plasmid pCE1 contained the β-isopropylmalate dehydrogenase gene. Restriction analysis showed that the β-isopropylmalate dehydrogenase gene was located in the 1.4kb Bglll-EcoRl fragment and the BamRl site was inside the β-isopropylmalate dehydrogenase gene.

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To clarify the structure-taste relationships of flavanone and dihydrochalcone (DHC) glycosides, the new glycosides, naringenin 7-O-(2-O-α-D-fucopyranosyl-β-D-galactoside) (I), -7-O-(2-O-β-D-fucopyranosyl-β- D-galactoside) (II), -7-O-(2-O-α-L-fucopyranosyl-β-D-galactoside) (III), -7-O-(2- O-β-L-fucopyranosyl-β-D-galactoside) (V), -7-O-(2-O-α-L-rhamnopyranosyl-β-D-mannoside) (VI), -7-O-β-D-galactoside) (XII), hesperetin 7-O-(2-O-α-L-fucopyranosyl-β-D-galactoside) (IV), naringenin DHC 4'-O-(2-O-α-D-fucopyranosyl-β-D-galactoside) (VII), -4'-(2-O-β-D-fucopyranosyl-β- D-galactoside) (VIII), -4'-O-(2-O-α-L-fucopyranosyl-β-D-galactoside) (IX), -4'-O-(2-O-β-L-fucopyranosyl-β- D-galactoside) (XI), -4'-O-β-D-galactoside) (XIII) and hesperetin DHC 4'-O-(2-O-α-L-fucopyranosyl- β-D-galactoside) (X) were synthesized.
The flavanones I, IV and XII had no taste but II, III, V and VI respectively tasted 0.05, 0.58, 0.39 and 0.75 times more bitter than naringin. Compounds VII and VIII were tasteless but IX, X, XI and XIII were found to be 1.46, 4.80, 1.04, and 0.90 times sweeter than saccharin, respectively, on a molar basis.

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The threonine operon of Escherichia coli was cloned in plasmid pBR322, using a threonine producing mutant, βIM4, as the DNA donor. A recombinant plasmid, pAJ294, that contains the whole threonine operon was obtained. No. 29-4, a transformant of βIM4 with pAJ294, had about eleven copies of pAJ294, five times higher homoserine dehydrogenase activity (coded by the thrA gene), and about three times higher threonine productivity than those of βIM4. No. 29-4 produced 13.4g/liter of L-threonine from 30 g/liter of glucose in the culture medium.

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The monosaccharide composition of cell wall material (CWM) in the cassava tuber and the contents of the other constituents were determined for more advanced industrial utilization. Starch, 80% ethanol-soluble sugar, uronic acid, lignin, ash, and CWM contents in the cassava tuber 86.1, 2.4, 3.4, 0.5, 0.9, and 4.5%, respectively. Rhamnose, fucose, arabinose, xylose, mannose, galactose, and glucose contents in CWM were 1.9, 1.2, 2.6, 4.2, 2.0, 12.8, and 52.7%, respectively. Then, the degradation pattern of CWM by enzymatic and sequential acid hydrolysis was studied. Aspergillus niger cellulase preparation was the most effective, and 57. 1 % of CWM was degraded by the enzyme preparation. On the other hand, about 50% of the hemicellulose part was extracted from CWM by hot water only.

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The levels of free amino acid, ammonia nitrogen and guanidino compounds were examined in renal failure rats induced by adenine. Among the essential amino acids in the serum, the marked reduction of lysine, valine, leucine and isoleucine was confirmed in the adenine-fed group as compared with the control group. Tyrosine and ornithine were also significantly reduced in the adenine-fed rats, while glycine, arginine and aspartic acid were significantly elevated. The urinary excretion of leucine, isoleucine and non-essential amino acids (glutamic acid, histidine, aspartic acid, citrulline, tyrosine, ornithine) was found to be high. On the other hand, adenine administered orally caused hyperammonemia. Furthermore, the results of the present study show that intake of adenine increased extraordinarily the level of guanidinosuccinic acid and methylguanidine in the serum, while the value of serum guanidinosuccinic acid and methylguanidine in rats fed on a control diet was not detectable.

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Several glycolipids were isolated from Spirulina maxima, an edible blue-green algae, by systematic fractionation with different solvents. Structural investigation by using methylation, GC- MS, and enzymic techniques indicated that the major glycolipids are O-β-D-galactosyl-(1→1')- 2', 3'-di-O-acyl-D-glycerol, O-α-D-galactosyl-(1→6)-O-β-D-galactosyl-(1→1')-2', 3'-di-O-acyl-D- glycerol and 6-sulfo-O-α-quinovosyl-(1→1')-2', 3'-di-O-acyl-D-glycerol. Main fatty acid components of these glycolipids were identified as palmitic acid and linoleic or linolenic acid. Based on these fatty acid compositions, Spirulina glycolipids were compared with those in higher plants.

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A series of mutants of Brevibacterium ammoniagenes selected for increased production of 5'- inosinic acid (5'-IMP) were analyzed for the size of their intracellular 5'-IMP and hypoxanthine (Hx) pools. All the mutants tested contained relatively large amounts of intracellular 5'-IMP in the earlier phase of growth irrespective of their 5'-IMP productivities, and the sizes of the pools corresponded fairly well to their 5'-IMP productivities. Furthermore, excretion of intracellular 5'- IMP by these mutants was measured by incubating the washed cells in a phosphate buffer at 30°C. In the absence of glucose in the reaction buffer, intracellular 5'-IMP of all the mutants except KY13102 was excreted partly as 5'-IMP and partly as Hx, after degradation, to the external buffer. However, accumulation of Hx in the external buffer was significantly repressed by glucose. Consequently in the case of the highest producer, KY13369, all of the intracellular 5'-IMP was excreted as 5'-IMP without degradation in the presence of glucose. These results suggest the existence of two excretion systems of internal 5'-IMP de novo synthesized ; a direct excretion system stimulated by glucose and an indirect excretion system coupled with degrading activity, which was repressed by glucose.

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Rabbit skeletal muscles were demonstrated to contain several inhibitors of cysteine proteases, cathepsins B and L, and papain.
Sephadex G-100 column chromatography exhibited two inhibitor peaks at the positions corresponding to 9, 500 and 52, 000 daltons, which commonly inhibited the above three cysteine proteases. There were two other peaks (corresponding to 21, 000 and 28, 000 daltons) inhibiting papain, one peak (25, 000 daltons) inhibiting cathepsin B and one peak (36, 000 daltons) inhibiting cathepsin L.
Muscle extracts contain an unknown factor which can degrade the inhibitors during incubation at pH 4.0 and 37°C. This factor is not cathepsin D.
Total inhibitor activities slightly changed on 9-day storage of rabbit skeletal muscle at 4°C, while the extractable activity of cathepsin L increased and that of cathepsin B slightly decreased.

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Myosin and its subfragments were prepared from rabbit skeletal muscle and studied in a differential scanning calorimeter. The characteristics of the observed endotherms were studied as a function of pH and salt concentration. An analysis of the DSC profiles for myosin and its subfragments in 0.6M KCl enabled the assignment of three components of the endotherms for myosin in solution to structural transitions in the head (globular) and tail (coiled-coil) regions of the molecule. However, large shifts for the T_m values as well as the reduction of the number of transitions were observed upon changing pH and salt concentration of the basal media. Comparison of the calorimetric behavior of myosin and its helical subfragments at a high salt concentration (0.6M KCl) with those at a low salt concentration (0.1M KCl) showed them to be remarkably different, suggesting that the DSC profiles at low salt concentrations are represented by the filaments of myosin and paracrystals of helical subfragments, wherein intermolecular interactions stabilize organized molecules through their self-associating properties.

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