Blasticidin S deaminase (EC 3.5.4.23) was purified by affinity chromatography using a column of Sepharose 4B coupled with pyrimidinoblasticidin S as a ligand. The Michaelis constant Km and the maximum velocity V_max varied with pH, which suggests that enzyme ionization is important either for substrate binding or for catalytic activity. The inflection point at pH 8.6-8.9 in the plot of pKm versus pH was attributed to an enzyme amino group which corresponded to the carboxyl group of substrates, and an inflection at pH 5.3 in the log V_max-pH plot was assigned to the imidazole group of histidine, which appeared to be critical for catalytic deaminohydroxylation. The binding of substrates by the enzyme was inferred to be promoted thermodynamically, and activation of the substrate-enzyme complex was presumed to proceed endothermically. From the results obtained, a hypothetical mode of reaction for blasticidin S deaminase is proposed.

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Most of the organic solvents tested were found to stimulate the mutagenicities of some mutagenic compounds. These stimulated compounds were restricted to the sugar-degradation products among various mutagenic compounds. From reduction of Nitro Blue tetrazolium (NBT), it can be said that all of the sugar-degradation compounds tested formed oxygen radicals in alkali conditions by autoxidation, and it was confirmed that the rates of the reducion of NBT by these compounds were greatly stimulated by various organic solvents. Further, the depolymerization of DNA by sugar-degradation compounds was found to stimulated by organic solvents. These results demonstrate that organic solvents enhance the oxygen radical formation of these sugar-degradation compounds, which leads to the stimulation of their mutagenicity.

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An extracellular amylase was obtained from a culture medium of Bacillus cereus NY-14. This enzyme was purified to show a single band on disc gel electrophoresis by ammonium sulfate fractionation and Sephadex G-100 gel filtration to 1101-fold of the activity of the original culture liquor. The purified enzyme had a molecular weight of 55, 000, an isoelectric point of 6.13, an optimum pH of 6.0, and an optimum temperature of 55°C. The pH-stability range was wide; the enzyme retained more than 80% of its initial activity in the range of pH 5.5 to 12. It was stable below 35°C and required calcium ions for the stabilization. The action pattern of this enzyme on amylaceous polysaccharides was unique in that the predominant product was maltopentaose. The purified amylase could also digest starch granules of such plants as rice, barley, corn, and kuzu to produce maltopentaose as the main product.

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Streptomyces sp. No. B-1625, which was identified as a strain of Streptomyces antibioticus, is a typical producer of actinomycin, but also produces minor acidic antibiotic components (FA), besides actinomycins X₂, D and X_0β. The FA-components, which were obtained with a highproducing mutant, 11M-21, showed antibacterial and antitumor activities, and also similar visible and UV absorption spectra to those characteristic of actinomycin. The FA-components were separated into five components, FA₁, FA_2α, FA_2β, FA_3α and FA_3β, on TLC. Among them, one component, FA_3β, isolated in a purified state as an orange powder, has a composition of C, 52.97: H, 6.34: N, 10.48%, and is active against B. subtilis at a MIC of 5 mcg/ml. The FA_3β component showed pK_a' of 5.4 and 12.0 and λ_max at 443, 427 and 233 nm. From these properties, FA_3β is considered to be an acidic actinomycin congener.

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Three forms of α-glucosidase (EC 3.2.1.20), designated as I, II, and III, have been isolated from suspension-cultured rice cells by a procedure including fractionation with ammonium sulfate, CM-cellulose column chromatography, and preparative disc gel electrophoresis. The three enzymes were homogeneous by polyacrylamide disc gel electrophoresis. α-Glucosidase I was secreted in the culture medium during growth, α-glucosidase II was readily extracted from rice cells with the buffer alone, and α-glucosidase III required NaCl to be solubilized. The molecular weights of the three enzymes were 96, 000 (I), 84, 000 (II), and 58, 000 (III). The three enzymes readily hydrolyzed maltose, maltotriose, maltotetraose, amylose, and soluble starch. α-Glucosidase I possessed strong isomaltose-hydrolyzing activity and hydrolyzed isomaltose about three times as rapidly as α-glucosidase III. The three enzymes produced panose as the main α-glucosyltransfer product from maltose. Half the maltose-hydrolyzing activities of the three enzymes were inhibited by 11.25ng of castanospermine. The inhibition was competitive.

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Maltosyl-α-cyclodextrin (6-α-maltosylcyclomaltohexaose, M-CD) was prepared from maltose and α-cyclodextrin by the reverse action of Bacillus pullulanase, and the action of α-amylases on this dextrin was examined. Among α-amylases tested, Thermoactinomyces vulgaris α-amylase (TVA) and Taka-amylase A (TAA) were found to attack the M-CD. Their action pattern on M-CD was studied. These α-amylases cleaved, first the cyclodextrin ring of M-CD, and the branched octasaccharides formed were immediately degraded to form glucose, branched tetraose, or pentaose, though the action pattern was different for TVA and TAA. In addition, TAA also split M-CD into glucose and glucosyl-α-cyclodextrin. Fission products at various stages of the reaction were separated and analyzed by paper chromatography and high performance liquid chromatography, their structures were analyzed, and the degradation pattern of M-CD was found.

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When mycelia of Streptomyces sp. No. 3137 were cultivated in a medium containing methyl β-xyloside, xylanases (EC 3.2.1.8) were inductively produced into the medium. Three types of enzyme from the culture nitrate have been purified by ultrafiltration with DIAFLO UM-10, chromatography on DEAE-Sephadex A-25, gel filtration on Bio Gel P-100, and isoelectric focusing with Servalyt 6-8 or 9-11. The three purified enzymes, tentatively named X-I, X-II-A, and X-II-B, were homogeneous by polyacrylamide gel electrophoresis at pH 4.3. The molecular weight of X-I was about 50, 000 by SDS-polyacrylamide gel electrophoresis or gel filtration on Bio Gel P-100. The molecular weight of X-II-A and X-II-B were both approximately 25, 000 by SDS-polyacrylamide gel electrophoresis and that of X-II-B was 25, 680 by the sedimentation-equilibrium method. X-I had an isoelectric point at 7.10, and X-II-A and X-II-B had different isoelectric points, 10.06 and 10.26, respectively. The three enzymes were optimally active at 60-65°C and stable to 55°C. The optimal pH of X-I, X-II-A, and X-II-B were pH 5.5-6.5, 5.0-6.0, and 5.0-6.0, respectively. The ranges of two X-II's pH stability (pH 1.5-11.5) were wider than that of X-I's (pH 3.0-10.5). These purified preparations hydrolyzed xylotriose, xylotetraose, and xylan but not xylobiose, cellobiose, maltose, carboxymethyl cellulose, or soluble starch. Their actions were inhibited by Hg²⁺ and Fe³⁺ ions, sodium dodecyl sulfate, and N-bromosuccinimide.

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Three xylanases produced inductively by methyl β-xyloside from ]itStreptomyces sp. No. 3137 were purified to homogeneity. Rabbit antisera against two xylanases, X-I and X-II-B, were prepared.
In double diffusion experiments, antiserum to X-I (anti-I serum) and antiserum to X-II-B (anti-II-B serum) formed a precipitation band with X-I, and X-II-B, respectively. No immunoprecipitate, however, was observed when xylanase X-II-A or X-II-B was tested against anti-I serum, and when X-I was done against anti-II-B serum. Anti-II-B serum formed a line of identity between X-II-A and X-II-B. The data indicate that X-II-A and X-II-B are closely related in immunology, while X-I is distinct.
The amino terminals were an alanine residue for X-I and threonine residues for X-II-A and X-II-B by the dansyl chloride method. The carboxyl terminals were an aspartic acid residue for X-I and an alanine residue for X-II-B by carboxypeptidase Y method.
Amino acid analysis showed that X-II-A and X-II-B had a large amount of glutamic acid and alanine residues, and a small amount of tyrosine, threonine, and serine residues compared with X-I.

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δ-Aminolevulinic acid (δ-ALA) synthases from Protaminobacter ruber and Rhodopseudomonas spheroides were highly purified and characterized. The molecular weights of the δ-ALA synthases from P. ruber and R. spheroides were estimated to be 97, 000 and 87, 000, respectively. The optimum pH was about 8.0 for both enzymes. The P. ruber-enzyme showed Kms of 1.05mM for glycine and 0.77μM for pyridoxal-5'-phosphate (PLP), while the R. spheroides-enzyme showed Kms of 8.33mM for glycine and 15μM for PLP. The P. ruber-enzyme was less stable during storage at 4°C or 37°C than the R. spheroides-enzyme. As to the effects of end-products, the P. ruber-enzyme was not inhibited by hemin, while the R. spheroides-enzyme was considerably inhibited by hemin. A higher concentration of vitamin B₁₂ stimulated the reaction of the δ-ALA synthases, especially the P. ruber-enzyme.

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In addition to the α-ALA synthase already reported (Fraction I: molecular weight, 100, 000; optimal pH, ca. 8.0), an isozyme (Fraction II: molecular weight, 64, 000; optimal pH, ca. 6.4) was found in Protaminobacter ruber grown in the dark after an initial light period (20-30hr). The fraction I- and II-enzymes were separable by gel-filtration through Sepharose 6B. While the former was formed constitutively, the latter was formed inducibly under the conditions for bacteriochlorophyll formation. Therefore, the fraction II-isozyme seems to be responsible for the biosynthesis of bacteriochlorophyll.

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We present a new method for isolating and purifying water-soluble arabinogalactan-proteins from cabbage and give their chemical properties. The water-soluble nondialyzable material from fresh cabbage was separated into three fractions (A-I, II, and III) by gel filtration on Sepharose CL-4B. A-I and A-II can be purified by HPLC. Borate is necessary to avoid formation of insoluble aggregates during isolation and purification. The molecular weights of A-I, II, and III were estimated to be 4.0×10⁵, 1.0×10⁵, and 1.0-4.0×10⁴, respectively. A-I and A-II are arabinogalactan-proteins with different carbohydrate/protein ratios: 5.5/1 for A-I and 11.4/1 for A-II. The carbohydrate moieties of A-I and A-II were both arabino-3, 6-galactans having D-galactose/L-arabinose ratios of 1.9/1 and 1.5/1, respectively. The amino acid composition indicates an abundance of hydroxyproline, serine, threonine and alanine, the sum of which amounted to about 50% of the total amino acids. A-I contained 1.5 times more hydroxyproline (20%) than A-II (14%), while A-II contained higher proportions of serine, glycine, and alanine. A-III was not a glycoprotein but was a mixture of carbohydrate and polypeptides.

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In addition to actinomycins D, X₂ and X_oβ, Streptomyces antibioticus No. B-1625 produces minor acidic actinomycin congeners (FA-components). To increase the production of the FA-components, improvement of medium constituents was attempted for both chemically denned and complex media. Addition of trace metals, especially FeSO₄, increased FA-components production and, moreover, the addition of sarcosine was found to increase the production of a selected component, B-1625 FA_2β. Finally, a complex medium, consisting of starch 3.0, Polypepton 0.1, meat extract 0.1, corn steep liquor 3.0, NaCl 0.3, CaCO₃ 0.3, sarcosine 0.1 and FeSO₄•7H₂O 0.05%, was developed for the increased production of FA-components, in particular, the selected component of B-1625 FA_2β.

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Two galactanases (I and II) were purified to homogeneous states from water extracts of a wheat bran culture of Penicillium citrinum. Although these enzymes were separable by affinity chromatography and distinct on polyacrylamide gel electrophoresis, they were similar in physical and enzymatic nature. They had almost the same molecular weight (3.5×10⁴) and isoelectric point (pH 4.2), and similar amino acid compositions and carbohydrate contents (3%). Alanine and leucine were detected for both enzymes as the N- and C-terminal amino acids, respectively.
These enzymes were most active at pH 4.5 and 55°C, and were stable between pH 4 and 10 (at 15°C for 24hr), and below 55°C (at pH 5.5 for 10min).
The enzymes hydrolyzed soybean arabinogalactan to produce galactose and several galactooligosaccharides, but did not attack coffee bean arabinogalactan. Therefore, these enzymes were suggested to be endo-1, 4-β-D-galactanases.
The enzymes also attacked ONPG and PNPG, and lag phases were observed at the beginning of the reactions.
Among the compounds examined, Hg²⁺ and Fe³⁺ inhibited the enzyme actions. ONPG-hydrolyzing activities of the enzymes were inhibited by some sugars such as lactose, galactose, arabinose, glucose and xylose.
Galactobiose, -triose and -tetraose prepared from soybean arabinogalactan with purified galactanase I were found to be further hydrolyzed by the enzymes. A lag phase was also observed in the time course of hydrolysis of galactobiose.

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The effects of the addition of individual amino acids on methionine-induced hypercholesterolemia (experiment 1), and the interacting effects of dietary protein level and sulfur-containing amino acids and glycine on plasma cholesterol concentration (experiment 2) were studied in growing rats fed on a high cholesterol diet. In experiment 1, rats were fed on a 25% casein-0.75% methionine (25CM) diet containing 2.5% of individual amino acids for 2 weeks. Methionine-induced hypercholesterolemia was prevented by the concurrent addition of glycine or serine, but the other amino acids tested (alanine, threonine, leucine, phenylalanine, lysine, arginine, and glutamic acid) had no effect. Histidine rather enhanced the hypercholesterolemia. In experiment 2, rats were fed on a 10%, 25%, or 50% casein diet containing 0.75% methionine, 0.60% cystine, 0.63% taurine, 2.5% glycine, or 0.75% methionine +2.5% glycine for 3 weeks. Dietary addition of 0.75% methionine increased the plasma cholesterol concentration for the 25% and 50% casein diets, but it decreased the plasma cholesterol for the 10% casein diet. When the addition level of methionine was doubled in the 10% casein diet, the plasma cholesterol concentration was significantly higher for the 1.5% methionine-added diet than for the 0.75% methionine-added diet. Cystine and taurine lowered plasma cholesterol for all dietary casein levels. Methionine-induced hypercholesterolemia with 25% and 50% casein diets was prevented by the glycine supplementation. These data suggest that sulfur-containing amino acids and glycine are important in plasma cholesterol regulation.

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Large and small starch granules were isolated and characterized from kernels of non-waxy (Bozu) and waxy (Yatomi mochi) barleys at their developmental stages of 8, 16, 28 and 40 days after flowering. The amylose content of the large and small granules of the non-waxy barley starch, as determined by the blue value and enzyme-chromatography, increased with the increasing age of the endosperm. Large granules of the non-waxy barley at any given developmental stage contained more amylose than small granules at the same stage, as in the case of mature non-waxy barley starches. Large granules of either the non-waxy or waxy barleys at any given developmental stage had a lower fraction III: fraction II ratio, one of the structural characteristics of amylopectin, than did small granules of the same cultivar at the same developmental stage. The amylose content in large granules of the waxy barley appeared to increase with the increasing age of the endosperm. The amylose content in small granules of the waxy barley at 8 days after flowering was 10%, although that at 16 and 28 days after flowering and at maturity was only 0-1%.

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The trigonelline content in coffee was determined by the microbiological assay method after demethylating the compound. The content was proved to be extremely high (up to 1% on the wet basis). When trigonelline was heated to above 180°C, it was converted into nicotinic acid. Although the conversion rate was low, a nutritionally significant amount of nicotinic acid was formed during roasting coffee beans because of the high content of trigonelline in coffee beans. The optimum heating condition for nicotinic acid formation was found at 220°C for 20min.

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Bacteroids retaining high acetylene reduction activity (nitrogenase activity) were prepared anaerobically from soybean nodules. Addition of succinate (or of both leghemoglobin and succinate) to the acetylene reduction assay system greatly increased the activity of the isolated bacteroids.
When various organic acids were incubated with the bacteroids at 2% oxygen concentration, an optimum condition for bacteroid acetylene reduction, the organic acid degradation by bacteroids was very slow, and both lactate and acetate were accumulated in the incubation system, suggesting the operation of fermentative pathway in bacteroids under such low oxygen conditions.
With 20% oxygen, the added organic acids were degraded rapidly by bacteroids without addition of leghemoglobin to the incubation system.
With leghemoglobin in the incubation system, the organic acid degradation by bacteroids was accelerated extensively even at 2% oxygen, and the formation of lactate and acetate were negligible. No significant difference in the organic acid degradation rate was observed between the 2% and 20% oxygen concentrations when the leghemoglobin was present in the incubation system. Addition of acetylene to the assay system slightly inhibited the organic acid degradation.
This data suggests that bacteroids are unable to oxidize organic acid in low oxygen concentration and that the leghemoglobin allows the rapid organic acid dagradation by bacteroids even in such low oxygen concentrations.

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Endogenous cytokinins in alfalfa were isolated, and identified by mass spectrometry. trans-Ribosylzeatin (RZ) and ribosyldihydrozeatin (DHRZ) were identified from the root, and the combined content (benzyladenine equivalent) was estimated to be approximately 0.5 μg/100g of fresh weight, cis- and trans-RZ were identified from the stems and leaves. The relative content of the cis-isomer was approximately five times greater than that of the trans-isomer.

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A remarkable effect of validamycin on the morphology of Rhizoctonia solani was seen after 2 days culture when the fungus was cultivated in a Roux flask with standing. In accordance with the morphological change, the production of laminarinase and glucan synthetase by the fungus was affected by validamycin.
The production of laminarinase was increased in the culture filtrate, and significantly decreased in the mycelium in the presence of validamycin. While the intracellular production of glucan synthetase in the culture with validamycin (10-50 μg/ml) increased by 40-60% compared with that in the control culture.

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Methionine requirements of male White Leghorn chickens were estimated at 5 stages of growth by growth and the recovery of ¹⁴C in respiratory carbon dioxide. The methionine requirement for maximum daily gain decreased with increasing age according to the equation; log Y= -0.0002431X-3.22, where Y and X represent the methionine requirement as percentage of the diet and g of average body weight of the chickens during the experimental periods that achieved maximum daily gain. The recovery percentage of ¹⁴C derived from methionine-1 -¹⁴C remained low, and then increased rapidly. The methionine requirement found from the recovery of ¹⁴C also decreased with increasing dietary methionine levels according to the equation; log Y= -0.0002161X-3.02, where Y and X represent the methionine requirement as percentages of the diet and g of body weights of chickens at the beginning of the recovery test for ¹⁴C. Dietary cystine spared the methionine requirement for growth, but did not affect the recovery of ¹⁴C in the respiratory carbon dioxide.

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Relationships between the structural (hydrophobicity and viscosity) and functional (foaming and emulsifying) properties of proteins were investigated by using a polymeric form of ovomucin (soluble type), and dissociated ovomucins which were treated with sonication (sonicated type) and reduction (reduced type). The soluble, sonicated and reduced ovomucins were ascertained to have excellent foaming and emulsifying properties. The foaming properties of the ovomucins decreased in proportion to decreases in the viscosity as the dissociation proceeded, in the order of the soluble, sonicated and reduced types. On the other hand, the emulsifying properties of ovomucins increased in proportion to increases in the surface hydrophobicity as the dissociation proceeded.
Thus, it was suggested that the foaming properties of ovomucins were dependent upon viscosity, and that the emulsifying properties of ovomucins were dependent upon surface hydrophobicity.

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The mechanism of C-C and ether bond cleavages of C_α- or C_β-deuterated β-O-4 and β-1 lignin substructure models and the vicinal diol compounds catalyzed by the enzyme system from Phanerochaete chrysosporium culture was investigated. The enzymatic oxidation of β-O-4 lignin model compounds in the presence of H₂O₂ and O₂ yielded C₆-C_α-derived benzaldehyde, and C_β-C_γ-derived product together with the arylglycerol product. Likewise, the β-1 models and the diol compounds also underwent the C-C bond cleavage, yielding C₆-C_α-derived benzaldehyde and the arylglycol product. The results demonstrated that the D-labels at C_α and C_β of the substrates were retained in the products after the C_α-C_β and ether bond cleavages.

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An assay system for cellulases which are active on microcrystalline cellulose (Avicel) has been designed, that is, the cellulase activity was effectively assayed in the presence of endo-glucanase and β-glucosidase. Using this system, two electrophoretically distinct cellulases, which are called FI-Avicelase and FIII-Avicelase, have been purified from the culture filtrate of Aspergillus aculeatus No. F-50 to homogeneity by DEAE- and SP-Sephadex column chromatographies, and gel filtration with Sephacryl S-200. The molecular weights of the FI- and FIII-Avicelases were estimated to be 109, 000 and 112, 000, respectively, and their isoelectric points to be 4.7 and 4.0. Both cellulases are glycoproteins containing 20 to 30% sugar, but they differ from each other in amino acid composition.

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The spheroplast membrane of Acetobacter aceti IFO 3284 was separated into outer and cytoplasmic membranes by alkaline sucrose density gradient centrifugation after treatment of the cells with lysozyme in sucrose-EDTA, pH 8.0. The cytoplasmic membrane, which was transparent and red colored, showed a specific gravity of 1.15 g/ml, and a number of protein components. High contents of heme b and heme c, and high enzyme activities of various membrane-bound primary dehydrogenases, which are characteristics of acetic acid bacteria, were found in the cytoplasmic membrane fraction. On the other hand, the outer membrane, which was white and turbid when homogenized, exhibited a high content of 2-keto-3-deoxyoctonate, and only four major polypeptides were observed on SDS-polyacrylamide gel electrophoresis. The outer membrane showed a specific gravity of 1.25 g/ml due to its high lipopolysaccharide content. A predominant species of the outer membrane proteins, tentatively designated as A1, was found to be heat-modifiable in SDS solution. The A1 peptide on SDS-polyacrylamide gel showed varied migration, from a position corresponding to 31, 000 daltons to one of 37, 000 daltons, when heated at over 60°C and then subjected to gel electrophoresis.

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Guinea pig liver transglutaminase was purified in a yield of more than 80% by a one-step purification procedure using an immunoadsorbent column of monoclonal antibodies. Active enzyme could be recovered by alkaline buffer desorption and quick neutralization. The purified enzyme was more than 98% homogeneous on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and had the same enzymological and immunological properties as those of the enzyme purified by conventional procedures.

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As model compounds for NADH coenzymes, three chiral Hantzsch ester-type dihydropyridines were prepared. By their use and 2, 6-dimethyl-3, 5-dicarbo-(-)-menthoxy-l, 4-dihydropyridine that had already been prepared, asymmetric reductions of unactivated prochiral ketones were conducted under the action of alkali metal derivatives at room temperature in a nonpolar solvent, and the alcohol product were obtained in a 36-80% chemical yield and 30-60% enantiomeric excess.

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A phytase was isolated and partially purified from pollen of cattail, Typha latifolia. Its maximum activity was at pH 8.0 and its Km value was 1.7 × 10^-5 M for phytic acid in the presence of Ca²⁺. Among divalent cations tested only Ca²⁺ affected the activity, increasing it by about 120%, but an excess was inhibitory. The enzyme was specific for phytic acid except for 6% activity (or p-nitrophenylphosphate. It seems to be a new type of phytase because it cleaved almost 50% of the total phosphate esters in phytic acid and was product-specific, yielding an inositol triphosphate as a final product.

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Methyl linoleate hydroperoxide was decomposed with 0.1 M HCl in acetone-water (9:1, v/v) at 30°C. The decrease in four isomers of the hydroperoxide was monitored by HPLC without any derivatization. In both isomers having 13- and 9-hydroperoxy groups, those having trans, trans dienes decomposed more rapidly than those having cis, trans dienes. In all the isomers, the rates of decomposition were first order with respect to concentrations of the hydroperoxides. The yields of 2-nonenal and 12-oxo-10-dodecenoate were also measured by GC-MS. 12-Oxo-10-dodecenoate was produced only from the 13-isomers and 2-nonenal from the 9-isomers. The rapid decomposition of the trans, trans isomers didn't seem to be responsible for the formation of these aldehyde products.

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α-Phenylsulfonyl alkanamides were synthesized, and their herbicidal activities were tested under paddy conditions. Some of the α-phenylsulfonyl propanamides showed a high herbicidal activity against paddy weeds with no significant effect on rice plants. The activity of the sulfonyl compound was superior to those of the sulfinyl and thio compounds.

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Acetalization of a steroidal ketone possessing an isopropylidenedioxy moiety in the other part of the molecule by acetal exchange with 2-ethyl-2-methyl-l, 3-dioxolane was found to give an acetal with a sec-butylidenedioxy moiety. By this additional exchange reaction, a new chiral center was generated in the sec-butylidenedioxy moiety, and hence an unnecessary stereochemical complexity was added. To circumvent the problem, 2, 2-dimethyl-l, 3-dioxolane was employed for the acetalization. By adopting this procedure, several intermediates in Mori's brassinolide synthesis could be obtained in pure and crystalline states. The present improved synthesis furnished 30 g of brassinolide in a 7.0% overall yield from stigmasterol, in contrast to 3.0% by the original procedure.

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Many 1, 2-benzisoxazole-3-acetamides were synthesized and their herbicidal activities in the paddy field were studied. Of the compounds tested, N-α, α-dimethylbenzyl-2-bromo-(1, 2-benzisoxazol-3-yl)acetamide 10a was the most effective. Details of the synthesis and the results of herbicidal evaluations are given.

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The larvicidal activities of benzimidazole derivatives with a terpenoid side chain on the rice stem borer and the silkworm were compared with such in vitro activities as the growth inhibition of the cultured integument of the rice stem borer and the respiration inhibition of rat liver mitochondria. Each larvicidal activity is parallel with these in vitro activities. The comparisons of their activities with those of rotenone and diflubenzuron indicate that the benzimidazoles mainly acted as respiration inhibitors in their larvicidal activity as well as causing cuticular growth inhibition. The activity of l-(3, 7-dimethyl-7-ethoxy-2-octenyi)-2-methylbenzimidazole, the most potent compound tested as a respiration inhibitor, was found to be about 6-fold higher than that of rotenone. In the respiratory chain, the site between NADH and ubiquinone was blocked, indicating that the larvicidal benzimidazoles shared a mode of action with those of rotenone, piericidins, and ubicidines.

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Lectin activity in immature pods from 30 strains of winged bean was investigated. Most of the lectin activity occurred in green shells and a small portion in immature seeds. Hemagglutinating activity of green shells was classified into four groups, according to the agglutination of trypsinized human type A, B, and O erythrocytes. Extracts from green shells of four representative strains which showed different hemagglutination patterns gave different elution profiles of lectin activity from ion exchange columns. Four types of lectin activity with different blood group specificities were apparently found in green shells.

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In an Escherichia coli K-12 strain (trpA trpE tna) cultured in LB broth without selective pressure, a pBR322 derivative bearing the E. coli tryptophan operon (pBR322-trp) was rapidly lost: after 27 cell-number doublings, only 7% cells retained both tryptophan prototrophy (Trp⁺) and ampicillin resistance (Ap^r), and 17% were Ap^r but Trp^-. Insertion of the mini-F DNA from F factor into this plasmid effectively suppressed both the plasmid loss and the discoordinate loss of Trp⁺: the percentage of Trp^- cells per cell-number doubling was decreased more than 100-fold. Partial derepression of the trp operon due to 3-indole acrylic acid further decreased the stability of the pBR322-trp but not that of the mini-F-inserted pBR322-trp.

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Mammalian choline dehydrogenase (EC 1.1.99.1) has been proved to be a quinoprotein in which pyrroloquinoline quinone (PQQ) is involved as the prosthetic group. The enzyme was purified from dog liver mitochondria by solubilizing the enzyme with Brij 58 and chromatographically separating it almost to homogeneity. The absorption spectrum of mammalian choline dehydrogenase indicated the presence of PQQ with a typical shoulder at 320 nm. Since PQQ was attached to the enzyme by a covalent linkage, the chromophore was isolated with an acid hydrolysate and the isolated chromophore gave rise the identical spectroscopic characteristics to that obtained from the amine oxidase of Aspergillus niger in which PQQ is covalently linked. The isolated chromophore potently activated apo-D-glucose dehydrogenase (EC 1.1.99.17) supporting the presence of PQQ in mammalian choline dehydrogenase.

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