A soluble xyloglucan was isolated from the buffer-soluble fraction of homogenates of etiolated mung bean hypocotyls. The general properties and structure of the soluble xyloglucan were similar to those of xyloglucan from the cell walls of etiolated mung bean hypocotyls. The molecular weight of the soluble xyloglucan was about 20, 000, whereas that of the wall xyloglucan was about 160, 000.
The origin of the soluble xyloglucan in the hypocotyl was investigated with special reference to the role of xyloglucan as reported by some authors. The results indicated that the ratio of the wall xyloglucan and soluble xyloglucan contents to total cell wall polysaccharides was different between elongated and non-elongated regions of etiolated mung bean hypocotyls. The enzyme responsible for the hydrolysis of xyloglucan is xyloglucanase and it was found in etiolated mung bean hypocotyls.

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A three-component enzyme system that catalyzes the oxidation of n-hexadecane to n-hexadecanol- 1 has been highly purified from Pseudomonas aeruginosa. The components were tentatively named Protein I, Protein II, and Protein III. Protein I gave an electron paramagnetic resonance signal at g=4.3 which is a characteristic of a nonheme iron protein, and the molecular weight of Protein I was estimated to be about 800, 000 by gel-filtration chromatography. Protein II purified until homogeneous by disc-gel electrophoresis exhibited the spectral characteristics of cytochrome c, and the molecular weight was about 50, 000 by gel-filtration chromatography. Purified Protein III, which gave a single sharp band after disc-gel electrophoresis, exhibited the spectral characteristics of a flavoprotein and had a molecular weight of about 12, 000 by gel-filtration chromatography. All three proteins were shown to be essential for this enzymatic activity in the presence of NADPH and O₂.

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The streptomycin-bleached, non-photosynthetic mutant of Euglena gracilis contained NADH-glyoxylate reductase, NADPH-glyoxylate reductase, glutamate-glyoxylate aminotransferase and serine-glyoxylate aminotransferase, in addition to glycolate dehydrogenase. Most activities of NADH- and NADPH-glyoxylate reductases and 75% of glutamate-glyoxylate aminotransferase activity in the crude homogenate were recovered in mitochondria.
The mutant cells grown under illumination contained three times as high glycolate dehydrogenase activity as the dark-grown cells. Illumination on the dark-grown cells caused an increase in activity to the level of the light-grown cells. Light at 420 nm wavelength was most effective for inducing the enzyme. The enzyme induced by illumination was the mitochondrial one and the specific activity increased 4-fold after illumination for 3 days; the rate of the increase was almost equal to the ratio of the rate of glycolate uptake from incubation mediumby the light-grown mutant to that of the dark-grown cells. However, there was no marked difference in the fate of carboxyl carbon of glycolate metabolized between the two types of cells.
It is concluded from these results that mitochondrial glycolate dehydrogenase participates mainly in the glycolate metabolism in the bleached mutant. This is supported by experiments on the metabolism of glycolate in isolated, intact mitochondria of the mutant. The physiological significance of the formation and metabolism of glycolate in the non-photosynthetic mutant of Euglena was discussed.

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A potent denitrifying bacterium, Alcaligenes faecalis S-6, was isolated from activated sludge, and the regulatory mechanisms for dissimilatory nitrite reductase (NIR) were studied. NIR activity was controlled by oxygen and nitrite through dual regulatory mechanisms, i.e., induced synthesis and inactivation of .the enzyme. Full induction of NIR synthesis required both low oxygen tension and the presence of nitrate or nitrite as inducer. Nitrite seemed to be the real inducer, since nitrate failed to induce synthesis with a nitrate reductase deficient mutant. Intracellular NIR was inactivated by oxygen, and the inactivation was stimulated by cysteine and prevented by nitrite.
NIR in the crude cell free extract was inactivated by oxygen when cysteine was added, but that in the partially purified preparation was not. An inactivating factor which may possibly be a protein catalyzing the inactivation was found in the cell extract.

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A strain of Moraxella sp. capable of assimilating fluoroacetate (FA) as the sole source of carbon was isolated. It was resistant to mercuric chloride and antibiotics, such as penicillin G and kanamycin. Mercury reductase and haloacetate halidohydrolase were found in the cell-free extract of the organism. Two kinds of halidohydrolase were found on purification by DEAE-cellulose column chromatography; one was active for FA and chloroacetate (CA) (halidohydrolase 1), and the other was active for CA but not FA (halidohydrolase 2). Two types of cured strain were obtained by mitomycin C; type I lost halidohydrolase 2, whereas type II became sensitive to mercuric chloride and lost halidohydrolase 1 and 2. On electrophoresis of plasmid on agarose gel, a plasmid band was observed in a wild strain and a shorter band in type I. However, no band was observed in type II. Transferring of the plasmid by conjugation from a wild cell to a type II cell gave an exconjugant which possessed halidohydrolase 1 and 2 and became resistant to mercury. These results indicate that both halidohydrolase 1 and 2 and also mercury reductase are determined by the plasmid in the organism.

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Haloacetate halidohydrolase II specified by a plasmid pUO1 was purified from haloacetateassimilating Moraxella sp. B. The purification procedures included protamine treatment, Ammonium sulfate fractionation, and column chromatographies with DEAE-cellulose, hydroxyapatite and Bio-gel P-150, resulting in a 200-fold purification. The purified enzyme was homogeneous by criteria of ultracentrifugation and disc electrophoresis.
The molecular weight estimated by Sephadex G-100 gel filtration was 43, 000, and it was 26, 000 by SDS-polyacrylamide gel electrophoresis. The sedimentation coefficient s⁰_{20, w} was 4.1 S, and the isoelectric point was pH5.2. The amino acid composition was also estimated.
The enzyme catalyzed the dehalogenation of monochloro-, monobromo-and monoiodoacetate, but not monofluoroacetate. 2, 2-Dichloroacetate and 2-chloropropionate were slightly dehalogenated, but trichloroacetate and 3-chloropropionate were not. The enzymewas very sensitive to inhibition with thiol reagents.

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The fate of O, O-dipropyl S-[2-(2'-methyl-1'-piperidinyl)-2-oxo-ethyl] phosphorodithioate (C 19 490, piperophos), an active ingradient of herbicides Rilof^® and Avirosan^®, was investigated in rats using 2-methyl [¹⁴C]-labelled material. After single oral doses (0.5 to 30 mg/kg body weight) the radioactivity was rapidly excreted, mainly through urine. Nine days after receiving a dose of 5.4 mg/kg the residues in liver, fat, kidney, muscle, blood and brain were below 0.03 ppm C 19 490 equivalents. Thirteen urine metabolites, representing 55% of the dose applied, were isolated and their structures elucidated by spectroscopic methods. The degradation of C 19 490 in the rat proceeds via hydrolysis of the thiolo phosphate followed by methylation of the sulfhydryl group. The methylthio derivative is either oxidized at the sulfur or hydroxylated at the piperidme moiety. Hydroxylation at the α-C leads via ring opening to carboxylic acids. The hydroxypiperidine derivatives are conjugated with glucuronic acid. No unchanged C 19 490 was excreted with the urine and the amount of ¹⁴CO₂ expired was below 0.5% of the dose.

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A toxin to the silkworm produced by Aspergillus flavus and A. oryzae was identified as cyclopyazonic acid. Detailed analysis of ¹³C NMR data of this compound is described.

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Two fungal strains, TG-1 and TG-2, utilizing triacrylonitrile (1, 3, 6-hexanetricarbonitrile, TAN) as nitrogen source, were isolated from soil and identified as Fusarium merismoides Corda var. merismoides and Fusarium solani (Mart.) Sacc. emend. Snyder et Hansen var. solani, respectively. F. merismoides TG- 1 could utilize TAN, adiponitrile, glutaronitrile, diacrylonitrile and 2, 4-dicyano-1-butene as nitrogen source. Conditions for cultivation of the strain were studied. Degradation products of TAN were isolated from the culture broth and determined to be a mixture of 5, 7- dicyanoheptanoic acid (62%) and 4, 7-dicyanoheptanoic acid (38%). A mixture of 5, 7- dicyanoheptanoic acid (11%) and 4, 7-dicyanoheptanoic acid (89%) was also obtained from the culture broth of F. solani TG-2.

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An enzyme catalyzing the degradation of secondary alcohol oxidase-oxidized poly(vinyl alcohol), in which hydroxyl groups of poly(vinyl alcohol) are partially converted to keto groups, was purified to an electrophoretically homogeneous state from a mixed culture broth of at least three different soil bacteria. The enzyme was active to the oxidized poly(vinyl alcohol), but not to intact poly(vinyl alcohol) and to a variety of examined low molecular weight keto compounds. The enzyme was, therefore, tentatively called oxidized poly(vinyl alcohol)-degrading enzyme. The enzyme was a single polypeptide having a molecular weight of38, 000. The N- and C-terminal amino acids were alanine and threonine, respectively. The isoelectric point was pH 10.0. The optimum pH for activity was 6.5 and the optimum temperature 45°C. The enzyme activity was inhibited by Hg²⁺ and recovered by reduced glutathione, although p-chloromercuribenzoate had no effect. The enzyme reaction on oxidized poly(vinyl alcohol) required neither oxygen nor other electron acceptors, and resulted in a rapid decrease in viscosity, a fall of pH and an increase in compounds that are positive to a color reaction specific to carboxylic acids. The infrared spectrum of reaction products also showed the presence of carboxylic acids. Based on these results, the reaction catalyzed by the enzyme has been suggested to be hydrolytic cleavages of the main chain of oxidized poly(vinyl alcohol) as in the equation:
An enzymatic system of poly(vinyl alcohol) degradation was reconstructed by use of purified samples of secondary alcohol oxidase and oxidized poly(vinyl alcohol)-degrading enzyme.

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The intestinal absorption of sfericase, a microbial serine proteinase producd by Bacillus sphaericus, was studied using acetyl-L-tyrosine α-naphthyl ester (ATNE) as substrate. This substrate was highly susceptible to sfericase, and with it, the minimum detectable concentration of sfericase was about 0.004 μg.
In experiments on intestinal absorption, sodium dodecylsulfate was added to the assay system at a final concentration of 0.1%, since at this concentration it inhibited more than 90% of the endogenous ATNE-hydrolytic activity of rabbit serum but only about 50% of that of sfericase, and thus permitted measurement of sfericase concentration in blood.
The concentration of sfericase in blood was maximal 2 hr after direct injection of sfericase powder into the intestinal tract, and absorption at this time amounted to 0.07% of the injected dose. On the other hand, the concentration in blood was maximal 3 hr after oral administration of entericcoated particles of sfericase, and the absorption amounted to 0.003%. These results suggest that sfericase is absorbed in active form.

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Disulfides, oxidized glutathione (GSSG) and cystine [(Cys)₂], were determined with a new fluorescent reagent N-(9-acridinyl)maleimide via corresponding thiols which were derived by the reduction with potassium cyanide. Linear relations were obtained between the fluorescence intensities and the disulfides concentrations ranged from 5 pmol/ml to 5 nmol/ml of GSSG and 5 pmol/ml to 2.7 nmol/ml of (Cys)₂, respectively. This method is 100-times more sensitive than the conventional colorimetric method. It enables determinations of disulfides in 2μl of urine, 6μl of blood and 0.6μg of tissues.

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The contents of noradrenaline, dopamineand serotonin per g wet weight of reduced cerebra of methylazoxymethanol-induced microencephalic rats were higher than those of control rats on all postpartum days, but the total amounts of these amines per cerebrum did not differ between microencephalic and control rats, except for total amounts of noradrenaline on day 21, and dopamine on days 10 and 21.
There was no difference in monoamine oxidase activity per g wet weight of cerebral regions between microencephalic and control rats on days 0 and 21, although the enzyme activity per g wet weight of cerebral regions of 90 days old microencephalic rats was 10-20% higher than that of control rats. Total monoamine oxidase activity per cerebrum of microencephalic rats was lower than that of control rats at all ages.
In the remaining portion of the brain, midbrain-colliculus and cerebellum which were not affected morphologically by methylazoxymethanol, there was little difference in biogenic amiiie content and monoamine oxidase activity per g wet weight of tissue between microencephalic and control rats.

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The rate of autolysis after thawing in intact frozen krill (whole body, cephalothorax, and abdomen) and in its homogenates was studied by determining both the increase of TCA-soluble nitrogen and the change of protein pattern in SDS-polyacrylamide gel electrophoresis.
Autolysis in the intact state proceeded rapidly in the separated cephalothorax, but very slowly in separated abdomen. The pH dependence in autolysis differed between cephalothorax and abdomen homogenates, indicating differences in the proteolytic enzymes involved. Autolysis of intact whole body proceeded to an extent similar to that of intact cephalothorax, liberating about 30% of total nitrogen in 24 hr. The rapid autolysis of abdomen proteins in the intact whole body was attributed to the action of cephalothorax proteases which penetrate into abdomen.
Amongmuscle proteins, the myosin heavy chain (MW=206, 000) was degraded very rapidly and extensively during autolysis.

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Phenoloxidase (Diphenoloxidase EC 1.10.3.1) was purified from an aqueous extract of the larvae of the housefly Musca domestica vicina Maquart by a procedure involving affinity chromatography on a Sepharose 4B derivative of p-aminobenzoic acid and ethylene diamine, Sepharose 4B and Sephadex G-200 gel filtrations. The purified phenoloxidase was homogeneous on polyacrylamide gel electrophoresis. By this improved method, phenoloxidase was recovered in greater yield and specific activity as compared with our previous purification procedure.

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The purified debranching enzyme of rice seeds has been studied to determine its action on starch-like polysaccharides. An endo-fashion degradation was demonstrated that produced branched saccharides; however, a large quantity of maltose and maltotriose were produced from the β-limit dextrin of glutinous rice starch, even at an early stage of reaction. The V of the enzyme for β-limit dextrin was ten-times larger than that for glutinous rice starch, which suggests that the rapid liberation of A-chains in the β-limit dextrin may be due to their chain length rather than to their occurrence at the exo-position.

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Three different dihydrofolate reductases (I, IIa and IIb) were separated from cell-free extracts of the trypanosomid flagellate Crithidia fasciculata ATCC12857. The major reductase (IIa) was purified 2744-fold by column chromatographies on DEAE-Sephadex, CM-Sephadex, Sephadex G- 150 and folate-Sepharose 4B. The final preparation was homogeneous in electrophoretic analysis. Its molecular weight was estimated by gel filtration to be 110, 000 and consisted of two subunits with the same molecular weight of 58, 000. The optimum pH was 7.0. The enzyme activity depended on dihydrofolate and NADPH. Other folate derivatives, unconjugated pteridines and NADH were ineffective. Km values for dihydrofolate and NADPH were 1.1 and 2.7 μm, respectively. One mol of the enzyme reduced 755 mol of dihydrofolate per min at 30°C. The enzyme activity was inhibited by p-chloromercuribenzoate, N-ethylmaleimide and urea. It was also inhibited by anti-folates, such as methotrexate, aminopterin, pyrimethamine and trimethoprim, with I₅₀ values (concentrations required for 50% inhibition) of 1.4, 1.5, 6400 and 27, 000 nM, respectively.

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Tannic acid (TA) and proteins interacted on polyacrylamide gel after electrophoresis and formed water-insoluble complex which appeared on the gel as white and clear bands. The formation of the complex primarily depended on the pH and concentration of TA solution. The optimal pH and concentration of TA solution for complex formation on pH 4.3, 8.0 and 9.5 gels that were usually used in polyacrylamide gel electrophoresis, were established. In most proteins tested, a few micrograms per gel were detectable on the pH gels within 1 hr after electrophoresis: When Takaamylase A was localized on the gel with TA, the enzyme maintained activity in it, and the enzymatic activity was recovered in good yield from the gel. The use of staining technique in polyacrylamide gel electrophoresis is described.

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(-)-Mintsulfide [(-)-1], a new sulfur-containing sesquiterpene found in peppermint oil, was synthesized from (-)-germacrene-D[(-)-3] by a photochemical reaction and was confirmed to be (1R)-cis-2, 6-epithio-cis-8-isopropyl-1-methyl-5-methylene-cis-bicyclo-[5, 3, 0]-decane. The existence of 1 was confirmed in 13 of 74 essential oils analyzed.

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An nuclease inhibitor was isolated from cells of Monascus purpureus after 2 days cultivation, and the inhibitor was released into the culture fluid after 6 days when cell autolysis occurred. The inhibitor was positive in ninhydrin and Anthrone tests. The inhibitor was purified by column chromatographies on Sephadex G-25, Biogel P-2 and DEAE-Sephadex A25, and was homogeneous on disc gel electrophoresis. The molecular weight of the inhibitor was estimated to be about 2500 by Sephadex G-75 gel filtration. The inhibitor reduced the activities of Monascus nuclease (nuclease MP) and nuclease PI, when RNA or heat-denatured DNA was used as substrate, but did not affect nucleotidase activity of either enzyme. Snake venom phosphodiesterase was also inhibited to some extent. The action mode of the inhibitor was noncompetitive inhibition. This inhibitor was named NMP inhibitor.

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The active site of sugar beet α-glucosidase catalyzing the hydrolyses of maltose and soluble starch was investigated by kinetic methods. On experiments with mixed substrates, maltose and soluble starch, competition between the two substrates was observed. Lineweaver-Burk plots were linear, and the dependence of V and Km values on the fraction of maltose, f= maltose/(maltose + soluble starch) was in good agreement with that theoretically predicted for a single active site mechanism. From the dependence of V and Km values on pH, the ionization constants of the essential ionizable group 1 and 2 of the free enzyme, pKe₁ and pKe₂, were determined for each substrate: pKe₁=3.9, pKe₂=635 for maltose; pKe₁ =3J, pKe₂=6.5 for soluble starch. Both pKe₁ and pKe₂ shifted to higher pH with a decrease in the dielectric constant of the reaction mixture. The ionization heat of the ionizable group 2 was nearly zero kcal/mol in either maltose or soluble starch as substrate. Tris, erythritol, methyl-α-glucoside and glucono-δ-lactone competitively inhibited both maltase and glucoamylase activities. The inhibition constants were nearly the same for maltase activity as those for glucoamylase activity. From these results it was concluded that the enzymeattacked maltose and soluble starch by a single active site mechanism.

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An examination of glycopeptide fractions obtained by proteolytic digestion of microconidial invertase isozyme (P-2) of Fusarium oxysporum revealed two classes of polysaccharide chains differing in size and composition. The nature of the carbohydrate to protein linkages was studied, and P-2 had both N-glycosidic bondings between asparagine and N-acetylglucosamine, and O-glycosidic bondings between serine or threonine and mannose. Based on these findings, a tentative glycoprotein structure of P-2 is discussed.

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A dipeptidase capable of hydrolyzing L-Leu-Gly was purified from the extract of Streptococcus cremoris H61 by a method that included ammoniumsulfate fractionation, DEAE-cellulose chromatography, hydroxylapatite chromatography, rechromatography on hydroxylapatite and rechromatography on DEAE-cellulose. The purified enzyme exhibited homogeneity in disc electrophoresis. The molecular weight of the enzyme was estimated to be 100, 000 by Sephadex G-150 gel filtration. The enzyme exhibited optimum pH at 8.0 and was stable up to 50°C. It was activated by Co²⁺ and inhibited by EDTA, 1, 10-phenanthroline and bestatin. The Km value for L-Leu-Gly was estimated to be 5.0 mM. The enzyme showed a wide range of specificity on dipeptides but hardly hydrolyzed tripeptides.

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Circadian rhythmicity was investigated in isolated small intestine and mucosal epithelial cells from rats on restricted-feeding regimen (food available from 17 : 00 to 23 : 00 every day). In the isolated intestine, daily rhythms synchronized to meal-timing were found in the activity patterns of L-leucine, L-lysine and D-glucose transport, and mucosal γ-glutamyltransferase and sucrase, and in the rates of lactate formation from glucose; the nadirs occurred at 12 : 00 and the peaks at 23 : 00. These same patterns were also noted with the mucosal epithelial cells prepared at distinct times of day from rats on meal-feeding regimen. The fasted rat intestine responded to refeeding with prompt increase in transport activity, i.e., out of phase with the original rhythm. Intraperitoneal administration of cyloheximide suppressed the daily rise in leucine transport activity, indicating that the transport rhythm was entrained by or closely associated with the rhythmic fluctuation in protein synthesis in the epithelial cells, which in turns is cued by the feeding schedule. The kinetic parameters estimated for leucine transport, the apparent affinity constant for transport and the maximal transport rate, were significantly higher at high activity periods. It is suggested that the rhythmic increase in transport activity is not only associated with membrane hyperpolarization but may be mediated by the emergence of a high capacity transport system.

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mRNA was isolated from mammary glands of lactating cow by affinity chromatography on poly(U)-Sepharose. The mRNA was heterogeneous on 3% agarose gel electrophoresis in the presence of 6m urea. The molecular weight of the main peak was estimated to be 3.3×10⁵. The mRNA was translated in a cell-free protein synthesizing system derived from wheat germ extract, and the translation products were analysed by the indirect immunoprecipitation method using specific antisera for casein components. About 50% of the total protein directed by this mRNA was casein. The relative amounts of α_s1-, β-, and κ-casein in the translation products were nearly the same as those in bovine milk. The immunoprecipitates were analysed on sodium dodecyl sulfatepolyacrylamide gradient gel (15-20%) electrophoresis, and their mobilities were compared with those of dephosphorylated and non-glycosylated casein as standard, α_s1- and κ-Casein synthesized in vitro migrated more slowly than standard caseins, while synthesized β-casein migrated slightly faster than the standard β-casein.

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Reesterification of the fatty acid liberated during hydrolysis of triglyceride by lipase was studied by using four microbial lipases. The amount of esterified product (glycerides) was estimated by assaying incorporated [1-¹⁴C]oleic acid which was added to the reaction mixture in the course of triolein hydrolysis. The extent of esterification during glyceride hydrolysis differed among the four lipases. Rhizopus delemar lipase was found to esterify the most, followed by Penicillium cyclopium lipase. Lipases from Aspergillus niger and Geotrichum candidum did not show marked esterifying activity during hydrolysis of glycerides. Synthesis of monoolein from hydrolysis products (glycerol and oleic acid) was not observed for any lipase used in reaction mixtures for triolein hydrolysis. The esterifying activity that was observed during hydrolysis of triglyceride is considered to be one of the main causes for diversity in the time course of triglyceride hydrolysis by the four lipases.

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Alanine, cystine, cysteine, β-hydroxypyruvate, an amino acid mixture and glycolaldehyde, which were found to satisfy the vitamin B6 (B6) requirement of Escherichia coli B WG3, a pdxB mutant, by paper disc assay method, were examined about the effect on growth of the mutant in liquid cultivation. Alanine and β-hydroxypyruvate did not significantly affected growth under the culture conditions, whereas cysteine and cystine supported growth to someextent. The amountof B6 synthesized by the mutant in the amino acid-supplemented mediumwas from 0.05 to 0. 12 nmol per ml. The amountof B6 synthesized in the medium, which was supplemented with an amino acid mixture composed of L-cysteine, L-threonine and L-methionine, was about 0. 15 nmol per ml. This amount of B6 was lower than the amount (0.4 nmol per ml) biosynthesized in glycolaldehydesupplemented medium. The data suggested that growth of the mutant supplemented with amino acids could not be supported by only the B6 biosynthesized from them, because such amounts of B6 were much smaller than the amount of B6 (0.6 nmol per ml) required for full growth of the mutant in minimal medium.

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The possible physiological function of nucleotide pyrophosphokinase (EC 2.7.6.4) which synthesizes a great variety of 3'-pyrophosphorylated nucleotides, including ppGpp, pppGpp and pppApp has been studied. Acriflavin treatment eliminated the production of this enzyme by Streptomyces morookaensis and suggests the possible involvement of plasmid: Irrespective of the ability to produce the enzyme, all Streptomyces species so far tested accumulated ppGpp and some pppGpp, whereas other highly phosphorylated nucleotides could not be detected. Furthermore, both the enzymeproducing and non-producing strains accumulated similar quantities of ppGpp. These results indicate that the enzyme does not operate in vivo, at least under normal growth conditions.

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This report identifies and describes the chemical structure of granular material that accumulates in the cytoplasm of Selenomonas ruminantium grown in glucose or lactate medium. The granular material was identified to be glycogen. Its molecular weight was about 2×10⁷ daltons. Conversion into maltose with α-amylase, β-amylase, and isoamylase was 61%, 37%, and 15%, respectively. The glycogen was digested completely byjoint action of β-amylase and isoamylase, and its conversion into maltose was 103%. The average chain length of the glycogen was 23.5. The maximum absorption of the iodine complex of the glycogen was at 520 nm. These results led us to conclude that the chemical structure of this glycogen was similar to that of plant amylopectin, unlike normal microbial or animal glycogen so far known. When S. ruminantium was grown in glucose medium, the amount of glycogen in cells reached about 260 μg/mg dry weight of cells during late exponential phase and early stationary phase.

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Ten strains of non-sulfur purple photosynthetic bacteria were isolated from soil and water samples gathered in Bangkok and its surrounding area. The isolated strains from Thailand were divided into two groups, A1 to A4 and B1 to B6. They were identified as Rhodopseudomonas gelatinosa and Rhodopseudomonas sphaeroides, respectively. All strains grew well either at 30°C or 40°C, but failed to grow at 45°C. Strains belonging to group A had weak activities of nitrogenase (acetylene reduction) and hydrogen production, while strains of group B showed much higher activities than group A. The activities of nitrogenase and hydrogen production of isolates in Thailand were compared with those of isolates in Japan. The activities of isolated strains in Thailand at 40°C were almost equal to those at 30°C or even higher. On the other hand, both hydrogen production and the nitrogenase activity of isolates in Japan decreased significantly at 40°C as compared to the activities at 30°C. These results suggest an intrinsic thermostability in hydrogen production by the non-sulfur purple photosynthetic bacteria of Thailand. Among isolated strains in Thailand, strain B5 was the most active in nitrogenase and hydrogen production, and its activity was significantly higher than strain TN3 at 40°C. TN3 had been selected as the most active strain among isolates in the Sendai area.

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Brdicka current (polarographic catalytic hydrogenevolution current produced by proteins in the presence of cobalt salt) of Streptomyces subtilisin inhibitor (SSI) and plasminostreptin (PS) was studied with dme and hmde. The Brdicka current of the inhibitors decreased with addition of subtilisin BPN' (S.BPN'), which was attributed to the formation of proteinase-inhibitor complexes. Analysis of the dependence of Brdicka current of SSI and S.BPN'-SSI complex on cobalt ion concentration revealed that one of two SS bonds of SSI becamenon-accessible to Brdicka reaction by the formation of proteinase-inhibitor complexes. SSI and PS could be titrated by polarographic method using Brdicka current. The titration curves were analyzed by a multiple equilibrium equation of complex formation. The polarographic method was proved useful for determining the dissociation constants of S.BPN'-inhibitor complexes as low as 10^-10 M.

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The effects of alkalic salts on the apparent viscosity of acid precipitated protein (APP) of soybean-suspending systems and heated gels were investigated using a modified coaxial cylinder viscometer. A hybrid program was established, (i) a cyclic temperature test (20→90→20°C) under a constant shear rate and (ii) a cyclic shearing test (48.7→243.7→48.7 sec^-1) under isothermal conditions. The apparent viscosity of protein suspending systems (12%, wt/vol) gradually decreased with increasing temperature to about 70°C. The apparent viscosity increased with a rise in temperature in the range of 70 to 90°C, in ascending order of Hofmeister's series.
SCN^->I^->Br^->Cl^->COOK^->F^->SO^2-₄, Li⁺>Na⁺>K⁺
With a fall in temperature, the apparent viscosity increased considerably in this order. The effect of anions to apparent viscosity was larger than that ofcations at all measured temperatures in the gel-forming period.

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β-N-Acetylhexosaminidase (EC 3.2. 1.52) was purified from the culture nitrate of Pycnoporus cinnabarinus to homogeneity by polyaerylamide disc gel electrophoresis. The ratio of β-GlcNAcase activity to β-GalNAcase activity remained constant during the purification process. The molecular weight of this enzyme was estimated to be about 120, 000 by gel nitration, and the isoelectric point was at about pH 5.4. The optimum pH was at 2.2 for pNPGlcNAc and around 3.7 for pNPGalNAc. The enzyme was relatively stable at acid pH range of 2-4 (for 45 hr at 5°C) and below 45°C (for 10 min at pH 2.8). The enzyme hydrolysed chito-oligosaccharides, such as N, N-diacetylchitobiose, N, N, N-triacetylchitotriose and N, N, N, N-tetraacetylchitotetraose.

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A rapid and simple method for assaying nematicidal activity was devised. This method is based on living nematodes descending through Japanese paper. Amongdicarboxylic esters tested against a root lesion nematode Prathylenchus coffeae, di-n-propyl, di-w-butyl and di-n-amyl succinates, and di-n-butyl esters derived from dicarboxylic acids showed marked nematicidal activities.

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The distribution of cysteine desulfhydrase activity in microorganisms was studied with intact cells. The enzyme activity was found mainly in strains belonging to Enterobacteriaceae, especially to genus Aerobacter (Enterobacter). Aerobacter cloacae IFO 12009 showed markedly high activity.
L-Cysteine was essential as an inducer of the enzyme formation, of which 0.2% in the mediumis appropriate.
Intact cells of bacteria containing high cysteine desulfhydrase activity, prepared from broth cultured for 19 hr, catalyzed the synthesis of L-cysteine from pyruvate, ammoniaand hydrogen sulfide.

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Cysteine desulfhydrase catalyzes β-replacement, the reverse reaction of α, β-elimination, as well as a, β-elimination. These reactions were studied with intact cells of Aerobacter aerogenes 1-3-2 and Aerobacter cloacae IFO 12009 containing cysteine desulfhydrase.
L-Cysteine and its analogues were synthesized by replacement and reverse reactions using intact cells. β-Chloro-L-alanine, L-cysteine, S-methyl-L-cysteine, S-allyl-L-cysteine and L-serine were used as substrates together with hydrogen sulfide and methyl mercaptan to synthesize L-cysteine and S-methyl-L-cysteine via replacement reaction by intact cells. L-Cysteine synthesized from β-chloro-L-alanine was confirmed to be entirely in L-form after isolation and identification of the product. The reverse reaction for synthesis of L-cysteine and S-methyl-L-cysteine from hydrogen sulfide or methyl mercaptan, pyruvate and ammonia was also catalyzed by intact cells. β-Chloro-L-alanine was found to be the best substrate for synthesis of L-cysteine and S-methyl-L-cysteine by β-replacement reaction.

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The amino acid sequence of the cyanogen bromide (CNBr) fragment CB I from the Ala chain of ricin D, the largest of three CNBr fragments, was established by manual Edman degradation of the peptides obtained by tryptic, chymotryptic or peptic digestion of fragment CBI. The total number of amino acid residues of fragment CB I accounted for 140 (54%) out of 260 residues in the Ala chain of ricin D.

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Tryptic peptides from two cyanogen bromide (CNBr) fragments CB II and CB III of the Ala chain of ricin D were sequenced by manual Edman degradation. Chymotryptic or peptic peptides from the two fragments were isolated by Dowex 1×2 column chromatography to obtain overlaps for the tryptic peptides, and the complete amino acid sequences offragments GBII and CB III were established. The amino acid residues in fragments CB II and CB III accounted for 75 and 45 residues, respectively, of 260 residues in the Ala chain.
These sequences together with the sequence offragment CB I described in the preceding paper established the complete sequence of the 260 amino acid residues in the Ala chain. Some structural characteristics of the protein are also discussed.

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Using immunochemical technique thermal denaturation of soybean 11S globulin, dissolved in different ionic strength solutions (μ = 0-4.0) and heated at 100°C for 5 min, has been quantitatively studied. The curves of the percentage of antigenicity remaining were obtained as a function of salt concentration. The 11S globulin became strongly resistant to thermal denaturation with increasing both KCl and potassium phosphate. The stabilizing effect (in terms of percent antigenicity) was separated into three regions. At ionic strength below 0.7, potassium phosphate had no stabilizing effect while KCl had a slightly effect. The rise in stabilizing effect up to about 50%, near 1.0-1.5 μ, represented a second transition to a different denatured state which retains undissociated molecule. At rises up to 75-95%, near 2.5-3.5 μ, a different conformational state resulted in which thermally denatured 11S globulin maintained almost intact native conformation after heating. The selection of an adequate ionic strength of protein solution has enabled preparation of thermally denatured 11S globulins which have desired-residual amounts of structured regions.

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A convenient synthesis method for methylenomycin B and its homolog, methylenomycin A, has been developed. Methylenomycin B, 2, 3-dimethyl-5-methylene-2-cyclopentenone (3) was synthesized: i) by methylation of Mannich derivative prepared from morpholine and 2, 3-dimethyl-2-cyclopentenone (5) or ii) by treatment of formalin with sodio derivatives of 2, 3-dimethyl-5-formyl-2-cyclopentenone (7a) and 2, 3-dimethyl-5-ethoxalyl-2-cyclopentenone (7b), both of which were easily prepared from 5 and ethyl formate or ethyl oxalate. 2, 3-Dimethyl-2, 3-epoxy-5- methylenecyclopentanone (2) was similarly prepared from the epoxide compound of 5 and ethyl oxalate. The bioassay of methylenomycin B and its related compounds against bacteria (B. subtilis, S. aureus, Ps. aeruginosa and E. coli) was also conducted. Methylenomycin A (1) and its desepoxy compound (17) were also prepared from 4-carboxy-2, 3-dimethyl-2-cyclopentenone (15) in the same procedure as described above.

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5, 6-Unsaturated disaccharide derivative prepared from maltose via its 6-iodo derivative was treated with mercuric chloride, giving α-linked pseudodisaccharide in good yield, which contains cyclohexanonederivatives as constituents. On treatment with an acetic anhydride-pyridine mixture, the cyclohexanone constituents underwent β-elimination to be changed into a sole cyclohexenone moiety. Hydrogenation of the double bond between two carbon atoms and subsequent reductive amination of the carbonyl group gave aminocyclitol-containing pseudodisaccharides.

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