The effects of pyridoxal on the urinary excretion of nicotinamide metabolites such as N¹-methylnicotinamide (MNA), N¹-methyl-2-pyridone-5-carboxamide (2-Py), and N¹-methyl-4-pyridone-3-carboxamide (4-Py) were investigated. When a pharmacological amount of pyridoxal (500 μmol/rat) was intraperitoneally injected into rats, the MNA excretion from 0 to 5hr urine after the injection increased 5-fold, and concomitantly, the 2-Py excretion decreased by 1/2 and 4-Py excretion by 1/3. Therefore, the ratio of (2-Py+4-Py) to MNA excretion was decreased greatly (1/15) by pyridoxal loading. These changes were gone by the 5-10 hr urine after the injection. In order to investigate these changes, the rats were killed 2 hr after the pyridoxal injection, and the activities of liver nicotinamide methyltransferase, 2-Py-forming MNA oxidase, and 4-Py-forming MNA oxidase were measured. Nicotinamide methyltransferase activity was increased slightly by the pyridoxal loading, but, 2-Py-forming MNA oxidase and 4-Py-forming MNA oxidase activity decreased greatly. Therefore, it was found that the increase in the urinary excretion of MNA and the concomitant decrease in the urinary excretion of 2-Py and 4-Py might be due to the inhibition of 2-Py-forming MNA oxidase and 4-Py-forming MNA oxidase activities by the pyridoxal loading.

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An extracellular maltohexaose-forming amylase [EC 3.2.1.98] from Klebsiella pneumoniae mutant is a normal hydrolytic enzyme that hydrolyzes short-chain amylose (DP=23) to give about 40% maltohexaose. Transglycosylation from maltoheptaose to the 4-position of p-nitrophenyl α-glucoside was efficiently induced through the use of maltohexaose-forming amylase in an aqueous methanol solution. The enzyme specifically produced p-nitrophenyl α-maltoheptaoside (13% of the p-nitrophenyl α-glucoside) from maltoheptaose as a donor and p-nitrophenyl α-glucoside as an acceptor. The yield of p-nitrophenyl α-maltoheptaoside depended on the concentration of methanol solvent, the pH, and temperature. Furthermore, the use of the aqueous methanol system in the reaction not only improved the solubility of p-nitrophenyl α-glucoside but also greatly increased the formation of p-nitrophenyl α-maltoheptaoside, which is a useful substrate for assay of human amylase in serum and urine.

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A phosphodiesterase (EC 3.1.4.1) was purified to homogeneity from the fruit body of Flammulina velutipes. The enzyme had considerable activity toward oligonucleotides. The Km values were 0.66mM for ApA, 2.47 mM for (Ap)₂A, and 3.03 mM for (Ap)₃A. The enzyme hydrolyzed oligodeoxyribonucleotides as well as oligoribonucleotides. The oligoribonucleotides bearing a phosphate residue at the 3' end were not hydrolyzed by the enzyme. The enzyme hydrolyzed the oligoribonucleotides exonucleolytically from the 3' to 5' end. Thus the PDase of F. velutipes is considered to function in vivo as an Oligonucleotidase (EC 3.1.13.3), which efficiently converts oligonucleotides to 5'-mononucleotides in the cell.

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A glucomannan isolated from a Candida utilis mutant having a new chemotype was further studied by inhibition of the homologous precipitin reaction with oligosaccharides obtained from the glucomannan by partial acid hydrolysis and controlled acetolysis. Oligosaccharides having at least two consecutive α-(1→2)-linked mannose residues at the non-reducing end and gluco-mannopentasaccharide were effective inhibitors. Thus, it appears that the glucomannan had two groups of antigenic determinants, one corresponding to the side chains of two, three, and four mannose units connected by α-(1→2)-linkage, and the other corresponding to a side chain composed of an O-α-D-glucopyranosyl-(1→6)-O-α-D-mannopyranosyl-(1→2)-]-O-α-D-mannopyranosyl-(1→2)-D-mannose unit. These results support a probable structure of repeating units for the glucomannan presented previously. The relative susceptibility of intersaccharidic linkages to acid hydrolysis in the mannan is discussed.

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Water-soluble phospholipase B containing approximately 50% carbohydrate, purified to homogeneity from yeast cell washings of Torulaspora delbrueckii, was treated with endoglycosidase H (Endo-H), and about 75% of the carbohydrate associated with this enzyme was removed. The native and carbohydrate-depleted enzymes were compared. The phospholipase B activity was higher in the carbohydrate-depleted enzyme than in the native form. The enzymatic activation by the removal of carbohydrate was due to the increased affinity of the enzyme for the substrate. The carbohydrate-depleted phospholipase B was less stable upon incubation at 50°C and more susceptible to proteolysis by V8 protease. These results suggested that the carbohydrate of phospholipase B in yeast cells stabilizes the enzyme conformation and protects the enzyme from proteolysis.

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In order to study the formation of yellow pigment in a radish root extract, a model reaction was conducted. It was found that 4-meth¥ Ithio-3-butenv 1 isothiocyanate (4-MTBI) formed a yellow pigment in an aqueous medium by a reaction with i -ascorbic acid (L-AsA) and such dihydroxyphenolic compounds as catechol, hydroquinone, dopa, dopamine and caffeic acid. No yellow colored substance was formed when the other ten isothiocyanates were employed instead of 4-MTBI. Also, thiol compounds such as L-cysteine, dithiothreitol and the reduced form of glutathione had little effect on the formation of the yellow pigment. The possibility that a water-soluble degradation product of 4-MTBI participated in the formation of the yellow pigment is suggested.

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4-Methylthio-3-butenyl isothiocyanate (4-MTBI), the main pungent principle of radish (Raphanus sativus L.) root, was degraded in an aqueous medium, and the chemical structure of the main water soluble degradation product was studied. Isolation of the product was successfully performed by cross-linked polyvinylpyrrolidone column chromatography. From the MS, IR and NMR spectroscopy data, the product was identified to be enolated 2-thioxo-3-pyrrolidinecarbaldehyde. A degradation pathway for the pungent principle in an aqueous medium is proposed.

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Effects of nutritional conditions and insertion direction of the tryptophan synthase (TSase) gene into a plasmid vector on the plasmid stability and the production of TSase in high cell concentration cultures were examined using recombinant Escherichia coli (E. coli K12 IFO 3301) harboring pBR322trpAB(1) (the TSase gene was inserted at the EcoRI site of pBR322 in the clockwise direction) and pBR322trpAB(2) (counterclockwise direction). As to the effects of the insertion direction, the cells harboring pBR322trpAB(2) were slightly lower in the growth rate and the plasmid stability than those harboring pBR322trpAB(l). However, the former was higher in the productivity of TSase and the final cell concentration attained than the latter. On the other hand, the addition of organic nutrients, especially yeast extract, to TK-25 medium was very effective to improve the plasmid stability. Among the components of yeast extract, L-glutamic acid was found to be effective to improve both the plasmid stability and the production of TSase. When 1 g/l of L-glutamic acid was added to TK-25 medium, a mineral synthetic medium developed for a high concentration culture, 115 g (dry basis)/l of reeombinant cells were obtained in 14 hr and the expression of TSase was maintained at 240-300 U/mg-protein during the cultivation.

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Aspartate aminotransferase (AAT) of Methanobacterium thermoformicicum SF-4 was purified to a homogeneous state on polyacrylamide gel electrophoresis (PAGE) by DEAE-cellulose, Polybuffer Exchanger (PBE), Phenyl-Sepharose, and hydroxyapatite column chromatography. The molecular weight of the enzyme was estimated to be 57, 000 by both gel filtration and PAGE on a gradient gel. Subunit analysis by sodium dodecyl sulfate (SDS)-PAGE suggested its existence as a single polypeptide with a molecular weight of 50, 000. The enzyme showed its maximum activity at 60°C and at pH 8.5. The activity did not decrease to any extent after heat treatment at 70°C for 1hr at pH 7.5. Transamination activity on L-glutamate was about 4 times higher than that on L-aspartate and was also observed weakly on L-cysteine. Maleate was the most effective inhibitor, while glutarate and fumarate were less effective inhibitors.

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D-Helix-deleted bovine pancreatic phospholipase A₂ was designed using molecular mechanic calculations, and synthesized. Effects of the deletion on the enzymatic activity and on the structure were investigated. The enzymatic activity of the mutant protein was about 40% of that of the native one for a miceller substrate of 1, 2-dioctanoylphosphatidylcholine. Although the Michaelis constant of the mutant enzyme was not changed, the catalytic constant was decreased. The dissociation constant of calcium ion was also changed. ¹H NMR study revealed a slight conformational change around the active site of the mutant enzyme in addition to changes around the mutated region. The effect on the activity of the mutation seems to be due to the conformational changes around the active site.

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To express efficiently the gene for extracellular β-cyclodextrin glucanotransferase (β-CGTase) of an alkalophilic Bacillus sp. #1011 using the E. coli promoters (tac, trp and P_L promoters), three DNA fragments starting from the nucleotide positions +1, -18, and -48 of the translation initiation site of the gene were prepared and they were fused with the promoters. The maximum production of the enzyme, which was located mainly (90%) in the periplasm of the E. coli strain, was observed in the combination of the trp promoter and the β-CGTase gene starting from the -48 nucleotide position in the presence of the inducer, IAA. The production of the enzyme was increased to 5.5 times that by the E. coli harboring the original plasmid and to approximately 3 times higher than the extracellular production of the enzyme by the parental Bacillus sp. #1011. The properties including the stability and optimum in the high pH range (pH 9) of the extracellular β-CGTase from the alkalophilic Bacillus was conserved in the periplasmic enzymes of the E. coli cells.

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Serine acetyltransferase (SATase, EC 2.3.1.30), an enzyme which catalyzes the biosynthesis of O-acetyl-L-serine (OAS) from L-serine and acetyl-CoA, has been purified about 33, 000-fold with a yield of 11 % from leaf extracts of Allium tuberosum with a procedure involving heat treatment, ammonium sulfate fractionation, DEAE-Toyopearl chromatography, Ultrogel AcA34 gel filtration, and Blue-Toyopearl affinity chromatography, followed by a second filtration through Ultrogel AcA34. The isolated enzyme was apparently homogeneous as shown by PAGE with a specific activity of 231 units/mg protein. Besides this SATase activity the enzyme also had a significant level of cysteine synthase (CSase, EC 4.2.99.8) activity with a specific activity of 39.2 units/mg protein. The molecular weight of the enzyme was 650, 000 by gel filtration. Subunit analysis by SDS-PAGE yielded two kinds of protein bands with a large subunit molecular weight of 35, 000 and a small subunit molecular weight of 31, 000. The results of Western blotting analysis using anti-rape CSase IgG suggested that the large subunk could be the CSase subunit.

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A convenient synthetic method for the marine antibiotic (-)-malyngolide and its Stereoisomers was accomplished from a chiral α-alkoxyketone (4), which was readily available as a chiron. Chiral quaternary carbon synthons (5a) and (5b) as the key intermediates were constructed by the chelation controlled addition of Grignard reagent to 4.
The diastereomeric mixture of 5a and 5b was readily transformed into a separable mixture of lactones (7a) and (7b), each of which could be easily separated by silica-gel column chromatography. (-)-Malyngolide and its three steroisomers were obtained in optically pure form without the need for optical resolution.

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The synthesis of (2S, 3S, 4R)-N-tetracosanoyl-2-amino-1, 3, 4-octadecanetriol (5) was achieved in eight steps in a 23% overall yield starting from 3, 4, 6-tri-O-benzyl-D-galactopyranose (6), and then ceramide 5 was converted to (2S, 3S, 4R)-3, 4-di-O-benzoyl-N-tetracosanoyl-2-amino-1, 3, 4-octadecanetriol (16), a key intermediate for the synthesis of wheat flour glycosyl ceramides (1, 2, 3 and 4) in a 79% overall yield.

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A 2-naphthylamine-1-sulfonate (tobias acid)-degrading Pseudomonas strain was isolated from soil. This organism degraded 1-naphtha lenesu Ifonate and 2-naphthol-1-sulfonate as well as tobias acid. When the cells grown on a nutrient medium were incubated with tobias acid, 1-naphthalenesulfonate, and 2-naphthol-1-sulfonate, salicylate was temporarily accumulated in the culture medium. A salicv late-degrading enzyme and a gentisate-degrading enzyme were induced by salicylate and gentisate, respectively. On the other hand, the enzymes which degrade sulfonated naphthalenes to salicylate were constitutive. Ammonia, sulfate, and a small amount of sulfite were detected in the course of degradation of tobias acid. 2-NaphthoI-8-sulfonate or l-naphthol-5-suIfonate was converted into 2, 4-dihydroxybenzoate or 2, 6-dihydroxybenzoate respectively. Both cis-1, 2-dihydroxy-1, 2-dihydro-3-naphthalenesulfonate and sulfate were formed when the cells were incubated with 2-naphthalenesulfonate. It is suggested that tobias acid was degraded by 1, 2-dioxygenation in the initial process of the degradation pathway.

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The function of Cu²⁺ in the breakage of pBR322 ccc-DNA by D-glucosamine was investigated using agarose gel electrophoresis. The maximal stimulatory effects on the DNA breakage and • OH production were observed at the same concentration of Cu²⁺ in an aqueous solution of D-glucosamine. An aqueous solution of D-glucosamine containing ImM of Cu²⁺ generated less O₂^- and H₂O₂ than •OH. The generation of these active oxygens, either in the presence or absence of Cu²⁺, was affected little by the addition of DNA. Superoxide dismutase inhibited the DNA-breaking action of D-glucosamine in the absence, but not the presence, of Cu²⁺. Hydroxyl radical-scavengers inhibited the reaction in the presence as well as the absence of Cu²⁺ . The reaction in the presence of Cu²⁺ was inhibited by d-GMP and a different kind of DNA. An atomic absorption analysis showed that copper binding to pBR322 ccc-DNA was concentration-dependent. Cupric ions were found to bind to the ccc-DNA, and were found to stimulate the autoxidation of D-glucosamine via generation of active oxygen molecules, including, especially •OH.

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The uptake of taurocholate in rat small intestine was investigated with everted sacs and epithelial cells. It was ascertained by means of these assay systems that Na⁺ -dependent taurocholate transport would be confined to the distal ileum. The effect of fasting on the Na⁺ -dependent taurocholate transport was assessed using isolated epithelial cells from there. Fasting for 2 days led to a considerable decrease in the taurocholate uptake by the epithelial cells regardless of Na⁺ -dependent or -independent transport. When kinetic parameters (K_t, V_max) were obtained for net Na⁺ -dependent taurocholate transport from double-reciprocal plots of the taurocholate concentration against its corresponding transport rate, these values suggested that a diminution not in the affinity for taurocholate but in the quantity of "carrier" protein would have arisen from semi-starvation.

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The antibody binding sites (B-cell epitopes) on β-actoglobulin (β-LG) were surveyed by assaying the reactivity of the tryptic fragments of β-LG to mouse anti-β-LG antiserum with ELISA. Four peptide fragments (the residues ²¹Ser-⁴⁰Arg, ⁴¹Val-⁶⁰Lys, ₁₀₂Tyr-¹²⁴Arg, and ¹⁴⁹Leu-¹⁶²Ile) bound the antibodies. We considered that B-cell epitopes of β-LG were included in these fragments. Furthermore, these four tryptic fragments were also reactive with the antiserum to RCM β-LG. Therefore, the unfolding of the β-LG molecule is considered not to influence the localization of the antibody binding sites on β-LG.

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A wild-type parent of Brevibacterium lactofermentum was converted into an L-Tyr producer by three steps of genetic breeding. First, acquirement of m-fluoro-D, L-phenylalanine resistance (1, 000μg/ml) brought about MF1317 which produced 3.5g/l of L-Tyr and a byproduct of 2.8g/l of L-Phe. Second, increase in the drug resistance (5, 000μg/ml) gave MF358 that produced 6.4g/l of L-Tyr and a byproduct of 6.0g/l of L-Phe. Third, an L-Phe auxotrophic mutant (FT-1) derived from MF358 accumulated 16g/l of L-Tyr. In FT-1, L-Phe was not accumulated at all, but a small amount of anthranilate (0.4g/l) was. A key enzyme in the biosynthesis of L-Tyr, 3-deoxy-D-arabinoheptulosonate-7-phosphate synthase, was free from synergistic feedback inhibition by L-Tyr and L-Phe in the producers, and so L-Tyr accumulation occurred independently of L-Phe concentration in the production medium.

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Two kinds of 3-deoxy-D-arabino-hepturosonate-7-phosphate (DAHP) synthase genes were cloned from an L-Phe-producing mutant of Brevibacterium lactofermentum, AJ11957, which was resistant to m-fluoro-D, L-phenylalanine (mFP) and p-fluoro-D, L-phenylalanine (pFP) and which had DAHP synthase free from feedback inhibition. Both genes were cloned using a vector plasmid, pAJ1844, and the resulting recombinant plasmids were named pARl and pAR2. They had different structures on the restriction maps. Both plasmids, pARl and pAR2, conferred mFP and pFP resistance and L-Phe and L-Tyr productivity on a wild-type strain of B. lactofermentum, AJ 12036. The degrees of L-Phe-analogue resistance and aromatic amino acid productivity of the pARl-transformant were larger than those of the pAR2-transformant. The introduction of pARl to AJ12036 resulted in the alteration of DAHP synthase activity from a feedback-sensitive mechanism to a feedback-insensitive one accompanied by an elevated level of specific activity. A DAHP synthase deficient mutant of Escherichia coli was complemented by pAR2, but not by pARl. Characteristics of the two kinds of DAHP synthase genes are discussed.

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Eight chimeric insecticidal protein (IP) genes were constructed between the 130-kDa and 135-kDa IP genes of Bacillus thuringiensis subsp. aizawai, and expressed in Escherichia coli JM103 cells. The characterization of the produced chimeric IPs indicated that the variable region (VR1) in the aminoterminal half of the IPs is responsible for the insecticidal activity against larvae of Spodoptera litura and Plutella xylostella. The carboxy-terminal half of VR1 was important for the formation of the 60-kDa active fragment in the gut juice of S. litura larvae. Also, combination of the other two variable regions (VR2 and VR3), which were in the central and carboxy-terminal portions of the IPs, appeared to be related to the solubility of the IPs in the gut juice.

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A new ice-nucleating bacterium, KUEN-3, was isolated from strawberry leaves. The ice-nucleating bacterium was found in the pale yellow colony group. Strain KUEV-3 was identified as Erwinia uredovora from its taxonomical characteristics. When strain KUEN-3 was cultured aerobically in a medium consisting of Simmons-citric acid broth (pH 6.1) for 24 hr at 18°C, the ice-nucleating activity of strain KUIN-3 cells was obtained. The ice-nucleating temperature, T₅₀ (°C) was detected at - 2.8°C in cell suspensions (1.1×10⁸ cells/ml) of strain KUEN-3. The ice-nucleating temperature was significantly decreased by treating cell suspensions for 30min at 40°C and was completely lost by heating them at 90°C. The plot of ice-nucleating temperature versus treatment temperature (°C) is similar to the curve that was obtained for cell suspensions of another ice-nucleating bacteria. The susceptibility of cell ice nuclei to urea or protein-modifying reagents suggests that proteins participate in the ice-nucleating event.

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We found that the submerged spores of Scedosporium sp. A-4 grown on propane have both propane and 2-propanol oxidation activities, and that this fungus has both the activities grown on propane or 1-propanol and neither activity was expressed in those grown on propionic acid or glucose. The propane oxidation activity was inducible by propane, 1-propanol, 2-propanol, acetone, or 3-pentanol. The inducible oxidation activity on propane was repressed by glucose or usable carbohydrates except soluble starch, and completely by propionic acid. This induction was inhibited by cycloheximide and actinomycin D, and molecular oxygen was required in induction not only of propane oxidation activity but of 2-propanol oxidation activity.

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Pseudomonas stutzeri MO-19 produced two active forms of extracellular maltotetraose-forming amylase. Both forms, G₄-l and G₄-2, were purified to electrophoretic homogeneity. The molecular masses of G₄-1 and G₄-2 were 57 kd and 46 kd by SDS-polyacrylamide gel electrophoresis, respectively. An identical N-terminal sequence up to 20 amino acid residues and similar amino acid compositions were obtained from both forms, but different C-terminal amino acids, leucine from G₄-1 and alanine from G₄-2, were released by carboxypeptidase Y. By in vitro incubation with a culture supernatant containing protease activity, G₄-1 was converted into G₄-2 without any loss of the amylase activity. It was concluded that G₄-2 was a product derived by the limited proteolysis of G₄-1, and that the proteolysis occured in the C-terminal region of G₄-1. G₄-2 was more thermostable than G₄-1, and had a 20-fold higher Michaelis constant value for glycogen, which was 50 mg/ml against 2.3 mg/ml of G₄-1. G₄-1 adsorbed onto raw starch granules while G₄-2 did not.

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Acid phosphatases (EC 3.1.3.2) from the axis and cotyledon of germinating soybeans (Glycine max L.) were purified approximately 700-fold and 2100-fold, respectively, to electrophoretic homogeneity by ammonium sulfate fractionation, cation-exchange, concanavalin A-Sepharose 4B affinity, .and hydroxyapatite chromatographies. This report describes the purification and characterization of the enzymes from both axis and cotyledon. Acid phosphatases from both organs had the following similar properties, although they have some differences in substrate specificity, (i) The enzyme was a glycoprotein. (ii) The native enzyme of approximate molecular weight of 100, 000 consisted of two subunits, each with an apparent molecular weight of 50, 000. (iii) The optimal pH was approximately 5.7-5.8, and the enzyme was stable at the pH range of 5.3-8.0. (iv) The apparent Km value with p-nitrophenyl phosphate as a substrate was 3.7-4.0×10^-4 M. (v) The enzyme activity was inhibited by Cu²⁺, Zn²⁺, Pb²⁺, Mo₇O₂₄^6-, F^-, and PO₄^3- ions, (vi) The enzyme hydrolyzed various phosphorylated compounds non-specifically. (vii) The antiserum against the enzyme from axis cross-reacted to that from cotyledon.

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A new approach for the synthesis of (±)-(E)-2-amino-5-phosphono-3-pentenoic acid (E-APPA) is described. The key intermediate, (E)-5-acetoxy-3, 4-dehydronorvaline derivative 8, was prepared by [3, 3]-sigmatropic rearrangement of allyl acetate 7 in the presence of Pd(II) catalyst. The acetoxy group in 8 was transformed into the phosphonyl group to furnish (E)-APPA in a moderate yield.

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From the pollen of buckwheat (Fagopymm esculentum Moench), the bioactive substances in a rice lamina inclination test were extracted and partially purified by several chromatographic methods. They were derivatized with 9-phenanthreneboronic acid and dansylaminophenylboronic acid, and then analyzed by reversed-phase high-performance liquid chromatography with fluorimetric detection. The active compounds were identified as brassinolide and castasterone by co-chromatography using authentic samples. In addition, these brassinosteroids were rigorously identified as their bismethaneboronate derivatives by the gas chromatography/high resolution-selected ion monitoring method. These data clearly established the presence of brassinolide and castasterone in buckwheat pollen.

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A thermostable pyrimidine nucleoside phosphorylase has been purified from Bacillus stearothevmophilus JTS 859. The enzyme had a molecular weight of 85, 000, consisting of 2 identical subunits (M_w 54, 000). Its isoelectric point was 4.8. The Michaelis constants for 5-methyluridine, uridine, thymidine, and 2'-deoxyuridine were 0.32, 0.19, 0.46, and 0.58 mM, respectively. The optimal temperature of the reaction was 70°C. The enzyme was found not to be a SH-enzyme based on the following three points. First, the enzyme reaction was not inhibited by PC MB or iodoacetic acid. Second, the optimal pH of the reaction was broad, from 7.0 to 11.5. Third, the enzyme did not contain cysteine. The half-life of the enzyme was 15.1 hr in 20mM potassium phosphate and ImM 5-methyluridine (pH 7.0) at 70°C. Due to the high optimal temperature, the broad optimal pH range, and the long half-life of the enzyme, the enzyme is useful for practical applications.

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Sweet potato β-amylase was divided into two active fractions (named F-A and F-B) by modification with periodate-oxidized maltohexaose at pH 9.7. F-A and F-B isolated by exclusion chromatography using Sephadex G-200 corresponded to a pentamer of the enzyme with molecular weight of 31.5 × 10⁴ and a monomer with molecular weight of 6.4 × 10⁴, respectively. The contents of carbohydrate of the modified enzymes were 9.7% for F-A and 9.3% for F-B. The specific activities of F-A and F-B were 2, 059 and 1, 129 units/mg of protein and were reduced to 82% and 45% of that of the original enzyme, respectively. The modification of the enzyme with the oxidized maltohexaose was due to formation of a Schiff base between ε-NH2 groups of lysines of the enzyme protein and CHO groups of the oxidized maltohexaose.

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(±)H'-Epiinvictolide [(3RS, 5RS, 6SR, 1'SR)-3, 5-dimethyl-6-(l'-methylbutyl)-tetrahydro-2H-pyran-2-one] was synthesized in 11 steps from methyl 2-oxo-6-exo-methylbicyclo[3.1.0]hexane-1-carboxylate, using a cuprous iodide-mediated homoconjugate addition of Grignard reagent as the key step.

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Hypokinesia/hypodynamia was induced in the hindlimbs of rats by means of a suspension harness, and metabolic balance studies, especially regarding nitrogen, were performed with different dietary protein levels (5, 10, 20, 40 and 60% casein diets). During a 10-day period of hypokinesia, significant reductions in the food intake and body weight were observed, especially with the high protein (60% casein) diet. However, the total nitrogen balance was positive (only in the first 1-2 days was the nitrogen balance negative in the suspended rats fed with the low-protein (5% casein) diet), even with the 5 or 10% protein diet, and the body protein content was also increased, as compared with that in the non-suspended rats. On the other hand, as a significant decrease in body fat was observed, the loss of body weight may have been mainly due to this fat decomposition. Hindlimb muscle atrophy (gastrocnemius and soleus) and also adrenal hypertrophy were observed. It may be considered that suspension causes glucocorticoid-mediated muscle catabolism. These results show that significant muscle atrophy and parallel changes in nitrogen metabolism occur in suspended rats, and an investigation of the mechanism underlying these changes by suspension may provide a new approach for crew health in space flight or to a solution of the many different problems from prolonged bed rest.

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A culture similar to Streptomyces variabilis was found to produce a novel cyclic hexadepsipeptide antibiotic named variapeptin. Variapeptin is structurally related to azinothricin, A83586C, and citropeptin. The antibiotic was active against Gram-positive bacteria and showed cytotoxic activity against mammalian cells.

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Eleven gibberellins (GAs) were identified in extracts of mature seed of radish (Raphanus sativus L. cv. Taibyosobutori) by full-scan GC/MS and by Kovats retention indices. These GAs comprised seven 13-hydroxy-GAs [GA₁, 3-epi-GA₁, GA₈, GA₁₇, GA₁₉, GA₂₀ and a new GA, 12α-hydroxy-GA₂₀ (GA₇₇)] and four non-13-hydroxy-GAs [GA₉, GA₂₄, 12β-hydroxy-GA₂₄ (tentative) and GA₂₅]. The major GAs were GA₈, GA₂₀, GA₂₄ and GA₇₇.

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N-Acetyl-D-glutamate deacetylase and N-acetyl-D-aspartate deacetylase were found in cell extracts from Alcaligenes xylosoxydans subsp. xylosoxydans A-6. N-Acetyl-D-glutamate deacetylase was produced inducibly by N-acetyl-D-glutamate and was highly specific to N-acetyl-D-glutamate. N-Acetyl-D-aspartate deacetylase was produced inducibly by N-acetyl-D-aspartate and was highly specific to N-acetyl-D-aspartate.

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