Several 1-(5'-substituted phenyl-1', 3', 4'-oxadiazol-2'-yl)-3-chloro-4-substituted-2-azetidinones were synthesized by annulation of an acid on anils using POC1₃ and Et₃N and of an acid chloride on anils using Et₃N. Their antibacterial and antifungal activities are reported, and based on screening data attempt is also made to elucidate the structure-activity relationship.

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β-Galactosidase (EC 3.2.1.23) from Bacillus macerans was produced in a medium containing lactose. The enzyme was purified through the following steps: precipitation with ammonium sulfate, gel filtration on Sephadex G-100, chromatography on DEAE-Sephadex A-50, a second chromatography on DEAE-Sephadex A-50, and a second gel filtration on Sephadex G-100. Hexagonal plate crystals were formed when acetone was dropped into the purified enzyme solution containing calcium ion. The purified enzyme was homogeneous on polyacrylamide disc electrophoresis, and the molecular weight was estimated to be about 320, 000 by gel filtration on Sephadex G-200 and about 78, 000 by sodium dodecyl sulfate gel electrophoresis. The purified enzyme migrated as a single protein band in both assays of molecular weight. Therefore, the enzyme consisted of four probably identical subunits. The isoelectric point of the enzyme was about pH 4.4. The enzyme had its optimal pH at 6.5 and was stable between pH 6 and 9. The enzyme was relatively stable below 37°C but completely lost its activity after heating 60°C for 10min. The Michaelis constants were 2.0mM for p-nitrophenyl-βgalactoside and 30mM for lactose. The enzymic activity was completely inhibited by Ag⁺, Hg²⁺, Cu²⁺, and p-chloromercuribenzoate, and it was considerably inhibited by monoiodoacetic acid, trisaminomethane, and galactose.

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Cellooligomer-(EPOX)-Sepharose CL-2B affinity chromatography was used to further purify the main endo-cellulase fraction, E₃-II, obtained from the gastric teeth of the marine mollusc Dolabella auricularia. The cellulase component in E₃-II, which had a strong affinity for the adsorbent in the presence of 1.0 M NaCl, was effectively removed from the non-cellulase protein and separated into two fractions, one (E₃-II-N) with a low affinity and the other (E₃-II-A) with a high affinity for the adsorbent. E₃-II-A, the main component of E₃-II, was desorbed with a buffer solution without NaCl or by the addition of 10mM cellotriitol to the eluent with or without 1.0M NaCl, and it was purified 23.1-fold over the starting material. Fraction A, obtained by further purification of E₃-II-A by gel filtration, was a single protein band on SDS-PAGE (M.W.: 51, 000), and separated into seven protein bands on DISC-PAGE. At least six of the protein bands had individually been demonstrated to be the same molecular weight (M.W.: 31, 000) by Hedrick-Smith plots on DISC-PAGE as by gel filtration. Fraction A was most active at pH 6.3 and it had a typical endo-hydrolysis pattern on CMC.

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Six new teleocidin-related compounds (3-8) together with (-)-N¹³-desmethylindolactam V (9) were found in the culture broth of Streptoverticillium blastmyceticum NA34-17 producing tumor-promoting indole alkaloids. Compounds 3-8 proved to be a dimer of (-)-indolactam V(3), which bound through a methylene group at position 7, 2-oxy derivatives of (-)-indolactam V (4-7) and 14-O-methylteleocidin A-l (8), respectively. Their tumor-promoting activities are also discussed.X

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The effects of Bacillus antibacterial factor (BAF) on oxygen uptake, transport systems, and macromolecular synthesis were studied in S. typhimurium. BAF had essentially no effect on oxygen uptake when glucose, succinate, lactate, α-ketoglutarate, pyruvate, and NADH served as substrates, suggesting that the respiration chain is not a target for BAF. The incorporation of [¹⁴C]leucine, [¹⁴C]acetate, and [¹⁴C]glucose into the washed cells was not inhibited by BAF, suggesting that BAF dose not affect these transport systems. The incorporation of [¹⁴C]leucine, [³H]uridine, and [³H]thymidine into the unwashed cells showed that BAF strongly inhibited protein synthesis, but not RNA and DNA synthesis. BAF also inhibited protein synthesis in a cell-free system from S. typhimurium. These results suggest that the primary site of antibacterial action of BAF is in the process of protein synthesis.

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The combined use of Bacillus subtilis FHC 402-derived antibacterial factor (BAF) and hexametaphosphate (HP) inhibited the growth of E. coli. To elucidate the mechanism of the inhibition, the effects of BAF and/or HP on respiration, liberation of cellular components, and macromolecular synthesis were studied. HP liberated protein, LPS, and Mg²⁺ from the cells, suggesting damage to the membrane. Further, HP decreased oxygen uptake and the incorporation of [¹⁴C]leucine, [³H]uridine, and [³H]thymidine into the cells. In contrast, BAF did not damage the outer membrane nor enhance the effects of HP on the membrane. HP or BAF had little or no effect on the incorporation of labeled compounds into the TCA-insoluble fraction. The combined use of BAF and HP decreased the incorporation of [¹⁴C]leucine into the fraction much more than that of [³H]uridine and [³H]thymidine, suggesting that the combined use essentially inhibits protein synthesis but not RNA and DNA synthesis. BAF also inhibited protein synthesis in the cell-free system. The antibacterial action of the combined use of BAF and HP in E. coli seems likely to be that the damage to the outer membrane caused by HP enables BAF to penetrate the membrane and inhibit protein synthesis.

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The structure of the β-galactosidase inhibitor, galactostatin, isolated from Streptomyces lydicus PA-5726 was determined to be 5-amino-5-deoxygalactopyranose, in which the ring oxygen of galactose has been replaced by nitrogen. For this study, two derivatives of galactostatin were prepared by oxidation and reduction, respectively. The oxidation product of galactostatin was 5-amino-5-deoxygalactonic-δ-lactam (galactostatin-lactam) and the reduction product was 5-amino1, 5-dideoxygalactopyranose (1-deoxygalactostatin).

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Forty-two bacterial strains that produce calcium 2, 5-diketo-D-gluconate from 30% (w/v) D-glucose with yields of more than 70 mol% were isolated from various soil and fruit samples. They were small rod-shaped, gram-negative, non-spore-forming and facultatively anaerobic bacteria, and could be classified taxonomically into three groups. Representative strains (SHS 2003, ATCC 31623; SHS 2006, ATCC 31626; SHS 2008, ATCC 31628) of the latter were identified as members of the genus Erwinia. The DNA base ratios of these strains ranged from 46.3 to 48.7 mol% guanine plus cytosine.
The results of experiments using whole cells and cell extracts of these three strains suggested that D-glucose is oxidized to 2, 5-diketo-D-gluconate via D-gluconate and 2-keto-D-gluconate. No 5-keto-D-gluconate was detected in the culture broth throughout their cultivation. Most activities of enzyme(s) responsible for the oxidation of D-glucose to 2, 5-diketo-D-gluconate were found in the particulate fractions of these strains.

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The host-predator relationship between the pine-wilt nematode, Bursaphelenchus xylophilus, and the nematophagous fungus, Arthrobotrys ellipsospora Y4007, was investigated. An adhesive trapping knob comprises the trapping organ of this fungus. On scanning electron microscopy, ring structures and net structures were not observed at either the initial stage of trapping and or after prolonged contact of nematodes with hyphae for 5 days under the experimental conditions. This fungus produced hemagglutinating substance(s), which were detected in mycelia and in the cultural medium. This Arthrobotrys hemagglutinin was purified from the cultural filtrate and its specificity toward sugars was assayed. Out of 20 sugars (mono-, di- and oligosaccharides, sugar alcohols and N-acetylhexosamines) tested, only bovine submaxillary mucin inhibited the hemagglutination effectively. A partially purified non-proteinous fraction of the nematode-extract showed high affinity to the Arthrobotrys ellipsospora hemagglutinin and inhibited the hemagglutination completely at 0.0004%. Arthrobotrys hyphae treated with bovine submaxillary mucin lost their capture ability and over 80% of the added nematodes were recovered from the fungal mat by the Baermann funnel technique.

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The emulsifying activity of native and citraconylated globulins in sesame (13S) and soybean (7S and 11S) seeds was examined. Native 13S showed intermediate emulsifying activity between those of native 7S and 1 IS. The emulsifying activity and stability of all the globulins increased with citraconylation, but the emulsifying stability of 13S was lower than those of 1 IS and 7S. The surface hydrophobicities of all the globulins increased with the modification, the value of citraconylated 13S being 4 times that of native globulin. Enzymatic hydrolysis as an in vitro model system of digestibility indicated that citraconylated globulins had the same digestibility as the native globulins.

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The characteristic foaming property of coconut oil or palm kernel oil with one of the nonlauric oils under deep-fat frying was investigated. The foaming property of the mixed oil disappeared after random interesterification, by which new molecular species with an intermediate carbon number increased, while the fatty acid composition of the oil remained unchanged. Similar effects of interesterification were found in a model system of monoacid triacylglycerol mixtures having medium (C₈-C₁₂) and long (C₁₆-C₁₈) chain fatty acids. The foaming may depend on the disparity of the triacylglycerol molecular size in the mixed oil, regardless of the fatty acid composition.

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The neurochemical changes caused by supplementation of a limiting amino acid (methionine, lysine or tryptophan) to a 5% protein diet (soy protein isolate, corn gluten or gelatin) were investigated. The final levels of each supplemented amino acid were 2- or 4-fold each requirement level in the diets. The supplementation of methionine to the soy protein isolate diet reduced the contents of brain 5-hydroxyindoles (serotonin and 5-hydroxyindole acetic acid (5HIAA)). With lysine supplementation to the corn gluten diet, the brain 5-hydroxyindole contents did not change. Tryptophan supplementation to the gelatin diet caused a significant increase in the brain 5-hydroxyindoles. When rats were fed the soy protein isolate diet supplemented with methionine for a 5-hr period on one day (acute) or on 30 days (chronic), the concentrations of brain 5-hydroxyindoles sharply decreased and remained decreased for 30 days. Good correlations between serum tryptophan, and brain tryptophan and 5-hydroxyindoles were found on multiple regression analysis. These observations indicate that the supplementation of a limiting amino acid to a low protein diet (for improvement of the nutritional quality of the diet) -if the level of each supplemented amino acid is 2- to 4-fold the respective requirement- can cause major neurochemical changes, therefore, these neurochemical parameters may be considered as possible measures for the nutritional and safety evalution of diets.

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NAD⁺-Linked glycerol dehydrogenase (GDH) activity in Hansenula ofunaensis grown on glycerol was separated into three enzymes by a procedure involving DEAE-cellulose and DEAE-Sephadex A-50 column chromatographies. The oxidative activities toward glycerol of GDH I-1 and GDH I-2 were only detected when the concentration of glycerol was high, while GDH II showed significant activity with a low concentration of glycerol. The Km values for glycerol of GDH I-1, GDH I-2 and GDH II were 0.56M, 2.9M and 0.16M, respectively. The Km values for dihydroxyacetone of GDH I-1, GDH I-2 and GDH II were 0.40M, 0.36M and 1.7 mM, respectively. The oxidative activities toward 1, 2-propanediol of GDH I-1 and GDH II were 0.37- and 1.5-fold those toward glycerol, respectively. GDH I-2 showed significant oxidative activity toward ethanol, while GDH I-1 and GDH II showed no such activity. GDH I-2 was identical to dihydroxyacetone reductase induced in methanol-grown cells.

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For further clarification of the role of L-ascorbic acid (AsA) in the prolyl 4-hydroxylase reaction, the specificity of AsA for the decarboxylation of α-ketoglutarate (KGA) was studied using various reductants including AsA and its structural analogs. Decarboxylation of KGA was not observed in the absence of AsA. Erythorbic acid (ErA) was found to be as effective as AsA, and D-ascorbic acid was almost as effective as AsA in the reaction. Whereas, thiol compounds showed a very slight accelerating effect on the decarboxylation of KGA. L-Scorbamic acid (SCA) or erythroscorbamic acid (ErS), at a concentration 10-fold greater than AsA, showed a decarboxylation level of 40-45% that of AsA. Furthermore, in the presence of AsA, the pHdependence and concentration effect on the decarboxylation of KGA were different from those in the presence of SCA. Moreover, the Lineweaver-Burk plot of the inhibition by SCA of AsA showed that the mode of interaction of SCA with AsA may be apparently noncompetitive. From these results, it is suggested that, due to its planar ring system with an endiol group, AsA is a specifically suitable reducing compound for inducing the decarboxylation of KGA in the enzyme reaction.

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L-Ascorbic acid (AsA) is specifically required for the decarboxylation of α-ketoglutarate (KGA) in the prolyl 4-hydroxylase reaction, due to its structural characteristics. For further clarification of the role of AsA in proline hydroxylation, AsA and its oxidation products during proline hydroxylation were determined by high-performance liquid chromatography (HPLC) using a radioisotope analyzer as a detection system. AsA was oxidized in the uncoupled reaction system without a suitable peptide substrate or with an unsuitable one such as poly-L-proline. Furthermore, the oxidation of AsA occurred in the complete reaction, even in the presence of a high concentration of dithiothreitol (DTT) in the reaction solution. These results indicated that the uncoupled reaction inevitably occurred during proline hydroxylation and this uncoupled reaction was accompanied by the oxidation of AsA, which led to its consumption. The reaction pathway of this hydroxylation was also discussed.

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5-Oxo-L-prolinase (L-pyroglutamate hydrolase, EC 3.5.2.9) from Alcaligenes sp. F-137 has been purified to homogeneity as judged by acrylamide gel electrophoresis and ultracentrifugation. The molecular weight of the enzyme was about 106, 000 and 123, 000 by gel filtration and sedimentation equilibrium, respectively. Upon disc electrophoresis in 0.1% sodium dodecyl sulfate the purified preparation migrates as a single band of molecular weight 126, 000. The sedimentation coefficient (s^o_{20, w}) of the enzyme was 6.82 S by ultracentrifugation and its isoelectric point was pH 5.1 by isoelectric focusing. The enzyme catalyzed the hydrolysis of 5-oxo-L-proline to glutamate coupled with the hydrolysis of ATP to ADP and inorganic phosphate, stoichiometrically. K⁺ and Mg²⁺ were required for the enzyme reaction. Michaelis constants of the enzyme were 0.07mM for 5-oxo-L-proline and 0.32mM for ATP. The enzyme was maximally active at pH 7.8 and 50°C. The enzyme was inhibited by p-chloromercuribenzoate of N-ethylmaleimide.

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Oxalate oxidase (EC 1.2.3.4) was purified to apparent homogeneity from Pseudomonas sp. OX53. The molecular weight of the enzyme was about 320, 000 by Sephadex G-200 column chromatography and 38, 000 by sodium dodecyl sulfate disc electrophoresis. The isoelectric point of the enzyme was pH 4.7 by isoelectric focusing. This enzyme contained 1.12 atoms of manganese and 0.36 atoms of zinc per subunit. Besides oxalic acid, the enzyme oxidized glyoxylic acid and malic acid at lower reaction rates. The Michaelis constant of the enzyme was 9.5mM for oxalic acid at the optimal pH 4.8. The enzyme was stable from pH 5.5 to 7.0. The enzyme was activated by flavins, phenylhydrazine, and o-phenylenediamine, and inhibited by I^-, Br^-, semicarbazide, and hydroxylamine.

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Two β-glucosidases, G1 and G2, were purified from the culture supernatant of Penicillium herquei Banier and Sartory. Both the purified enzymes were homogeneous on polyacrylamide disc gel electrophoresis. The molecular weights of G1 and G2 were estimated to be 125, 000 and 122, 000, respectively, by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis. G1 and G2 contained 12.7% and 16.1% carbohydrate as glucose, and had isoelectric points of 5.02 and 5.24, respectively. Both enzymes had optimum pHs of 4.0-4.5 and optimum temperatures at 60°C, but pH- and thermo-stabilities of G1 were higher than those of G2. Both enzymes were active not only on p-nitrophenyl β-D-glucopyranoside, salicin, and the β-glucobioses tested but also on laminarin. CM-Cellulose was a very poor substrate for both enzymes. The activities of G1 toward the substrates except for laminarin and CM-cellulose were apparently higher than those of G2. Both enzymes acted on cellobiose to produce a transfer product.

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The apparent Km values of yeast α-glucan phosphorylase [EC 2.4.1.1] for glucose 1-phosphate, glycogen and maltopentaose were 1.3mM, 0.10mM and 8.8mM, respectively. The Km values for maltopentaose clearly distinguished the muscle and yeast enzymes from the potato enzyme. Comparison of the Km values for maltooligosaccharides in the directions of both glycogen synthesis and degradation showed the similarity of the muscle and yeast enzymes. Affinity-gel electrophoresis indicated that the dissociation constant of the yeast enzyme for maltoheptaose was 0.23mM, which was 26-fold smaller than the Km value for maltoheptaose (5.9mM). Inhibition of the yeast enzyme activity by glucose 6-phosphate and UDP-glucose was much stronger than that by fructose 6-phosphate and fructose 1, 6-bisphosphate. Moreover, tryptic inactivation of the yeast enzyme was greatly increased by UDP-glucose and glucose 6-phosphate. Based on the kinetic properties, a regulatory mechanism of the yeast phosphorylase was discussed in comparison with those for the muscle and potato phosphorylases.

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The effects of derivatives containing Lys-Asp sequences on growth-hormone-mediated lipolysis were examined for fat cells isolated from rat epididymal adipose tissue. A dipeptide, Lys-Asp, had a weak but distinct ability to induce lipolysis and inhibit growth-hormone-mediated lipolysis. Among the derivatives tested, Lys(Z)-Asp(OEt)-OEt (6d), Lys(Z)-Asp(OC₄H₉)-OC₄H₉ (6e), Lys(Z)-Asp(OC₈H₁₇)-OC₈H₁₇ (6f), C₇H₁₅CO-Lys(Z)-Asp (4b), and C₁₅H₃₁CO-Lys(Z)-Asp (4c) had a fairly high lipolytic activity. The derivatives 6e, 6d and 4c inhibited growthhormone-mediated lipolysis. A derivative, C₁₅H₃₁CO-Lys-Asp(OMe)-OMe (3c), had no lipolytic activity but strongly inhibited for growth-hormone-mediated lipolysis. It is suggested that charge groups in the Lys-Asp derivatives are responsible for lipolytic action and the hydrophobic hydrocarbon chains in the derivatives enhance the ability to induce lipolysis or inhibit the gorwthhormone-mediated lipolysis.

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Three extracellular β-mannanases (M-I, M-II, and M-III) of an alkalophilic Bacillus sp. (AM001) were purified to an electrophoretically homogenous state. Molecular weights and pi values of the purified enzymes (M-I, M-II, and M-III) were 58, 000, 59, 000, and 42, 000 by SDS-PAGE and 5.9, 5.7, and 5.1 by isoelectric focusing, respectively. These enzymes were most active at pH 9.0 and 60°C (M-I and M-II) and pH 8.5 and 65°C (M-III). The enzymes were activated slightly by cysteine, and-inhibited strongly by Ag⁺ and N-bromosuccinimide. Michaelis constants (Km) of the M-I enzyme for β-mannans from copra, locust bean, and konjak were 2.0, 3.8, and 7.7mg/ml, and maximum velocities (V_max) for these saccharides were 730, 1470, and 1880U/mg-protein, respectively. The kinetic properties of M-II and M-III enzymes were almost the same as those of M-I. About 22, 16, 15, and 2:5% of the β-1, 4-mannosidic linkages in β-mannans from copra, konjak, locust bean, and guar bean were hydrolyzed by the M-I enzyme, and the major components in the digests were di-, tri-, and tetra-saccharides. These enzymes hydrolyzed β-1, 4-mannooligosaccharides larger than mannotriose.

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Subcellular localization of β-conglycinin and glycinin in developing soybean cotyledons was examined by sucrose density gradient ultracentrifugation (SDG-UC). Two major bands appeared at densities of 1.05 and 1.15 in the SDG-UC. They were the microbody fraction and rER fraction, respectively, from the distribution of marker enzymes, electron microscopic observation, and the effects of MgCl₂ on the profile of SDG-UC. In the soluble and microbody fractions, α and α' subunits of β-conglycinin were major polypeptides. The amounts of β-conglycinin and glycinin associated with rER were roughly equal. β-Conglycinin was found in the soluble and microbody fractions as well as the rER fraction while glycinin was mostly localized in the rER fraction.

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The tetradecapeptide of a renin substrate, DRVYIHPFHLLVYS, was used as a substrate for assaying several fungal aspartic and acidic proteinases in the acidic pH range. Aspartic and acidic proteinases from Phycomycetes, Mucor and Rhizopus, and Deuteromycotina, Aspergillus and Penicillium, cleaved the tetradecapeptide at its tyrosyl⁴-isoleucyl⁵ (Y⁴-I⁵), histidyl⁶-prolyl⁷ (H⁶-P⁷) and leucyl¹¹-valyl¹² (L¹¹-V¹²) bonds in the acidic pH range, while acidic proteinases type B and type A-I from Scytalidium lignicolumn, and those from Cladosporium and Basidiomycetes, Pycnoporus sanguineus, and the yeast, Rhodotorula glutinis, showed slightly different specificities towards the tetradecapeptide. Pepsin primarily cleaved the valyl³-tyrosyl⁴ (V³-Y⁴) and leucyl¹⁰-leucyl¹¹ (L¹⁰-L¹¹) bonds. All of the aspartic and acidic proteinases of fungal origin tested in the present study have different specificities from that of pepsin.

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The effects of the trichothecene mycotoxins diacetoxyscirpenol, neosolaniol and T-2 toxin on the replication of herpes simplex virus type 2 (HSV-2) in HEp-2 cells were examined. The 50% inhibitory concentrations for HSV-2 replication were 2.3ng/ml for diacetoxyscirpenol, 52.0ng/ml for neosolaniol, and 1.6ng/ml for T-2 toxin. The addition of these toxins to the cells within 4hr after HSV-2 infection was necessary for the inhibition of the virus replication. Viral polypeptides synthesized in HSV-2-infected cells treated with the toxins were analyzed by immunoblotting using rabbit antiserum to HSV-2. The syntheses of early viral proteins were greatly inhibited when the toxins were added 1 hr after infection, and those of late viral proteins were also inhibited by toxin exposures 4hr through 6hr after infection. The toxins added after the completion of the latter protein syntheses affected the HSV-2 replication insignificantly. However, viral RNA synthesis was not inhibited when the toxins were added 1 hr after infection. These results indicate that trichothecene mycotoxins inhibit HSV-2 replication by blocking viral protein syntheses.

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An insulin-stimulating protein was isolated from soybean seed. This protein was the major component of a fraction which was adsorbed on cholic acid-conjugated Sepharose 4B, and is suggested to interact with bile salt anions in a specific fashion/The protein had no insulin-like activity per se, but it enhanced the in vitro inhibitory action of insulin on fat decomposition that was accelerated by epinephrine in rat adipose cells.

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The metabolic fate of the carbon skeletons of L-[U-¹⁴C]valine and L-[U-¹⁴C]isoleucine was investigated in growing rats fed with diets containing different percentages of protein calories (0, 5, 10, 15 and 30 PC%) at 4, 100 kcal of metabolizable energy per kg of diet. The nutritional significance of the metabolism of the branched chain amino acids is discussed.
The incorporation of ¹⁴C into the body protein from ¹⁴C-valine or isoleucine was about 80% of the injected dose in the 0 and 5 PC% groups, but it decreased with the increasing level of dietary protein from 10 to 30 PC%. The expired ¹⁴CO₂ production from ¹⁴C-isoleucine was depressed with reducing PC%, and then increased with higher PC% in the diets, showing a break point at 5 PC%, whereas a linear increase in ¹⁴CO₂ production was observed for labeled valine with increasing of the dietary protein level. The conversion of the carbon skeleton of ¹⁴C-valine into the body lipid was the lowest among the branched chain amino acids, reflecting its glycogenic property.
These results indicate that the metabolic response of the carbon skeleton of valine and isoleucine to dietary protein level changes at around 10 PC%, at which the growth rate and body protein retention reached approximate maxima.

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To estimate the steric distance between the bitter taste determinant sites in peptides, some cyclic dipeptides, amino acid anilides, amino acid cyclohexylamides, and benzoyl amino acids were synthesized and their tastes were evaluated. The diketopiperazine ring of cyclic dipeptides acted as a bitter taste determinant site due to its hydrophobicity. The steric distance between 2 sites was estimated as 4.1 Å from the molecule models of cyclic dipeptides composed of typical amino acids in the bitter peptides. Due to the hypothesis of two bitter taste determinant sites, which bind with the bitter taste receptor via a "binding unit" and a "stimulating unit, " a mechanism for the bitterness in peptides was postulated.

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An isomalto-dextranase was highly purified from the cell-free culture broth of Arthrobacter globiformis T6 by consecutive column chromatographies on CM-cellulose. The final purified enzyme was judged to be homogeneous on polyacrylamide gel, SDS-polyaerylamide gel and ampholine electrophoresis.
The isopullulanase to G₂-dextranase activity ratio was almost the same (ca. 0.18%) at each purification step. The isopullulanase activity appeared at exactly the same position as the G₂-dextranase activity on CM-cellulose column chromatography, analytical polyacrylamide gel electrophoresis and isoelectric focusing. The stabilities of the isopullulanase as to pH and temperature well coincided with those of the G₂-dextranase. Furthermore, the inactivation profiles of the isopullulanase with various metal ions and inhibitors were almost the same as those of the G₂-dextranase. From these results, it was strongly suggested that a single enzyme molecule was responsible for both the G₂-dextranase and isopullulanase activities.

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The complete amino acid sequence of metallothionein II isolated from kidneys of the striped dolphin, Stenella coeruleoalba, is reported. The sequence was established by a gas phase protein sequencer using the fragments obtained by cyanogen bromide cleavage and protease digestions of the S-carboxamidomethylated protein. The N-terminal was identified as acetylmethionine by ¹H-NMR and MS using the N-terminal dipeptide obtained by formic acid hydrolysis. The C-terminal amino acid was assigned as alanine using both carboxypeptidase and trypsin digests. Remarkable sequence homology was observed between dolphin and mammalian metallothionein II,

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Two types of 130kDa insecticidal protein genes isolated from large plasmid DNAs of Bacillus thuringiensis var. israelensis HD522 were cloned in an Escherichia coli plasmid vector. Analysis of the nucleotide sequences revealed that the two genes encoded a 127, 500-dalton protein (ISRH3) consisting of 1, 135 amino acids and a 134, 400-dalton protein (ISRH4) consisting of 1, 180 amino acids. The two insecticidal proteins were identical in a region of the C-terminal 467 amino acids.

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