The hypocholesterolemic action of grifolin was investigated in terms of its structur-activity relationship with rats fed on a high-cholesterol diet. The results show that the structure of farnesylorcinol was required for the hypocholesterolemic action, and that the effect of grifolin might be elicited, at least in part, through the augmented excretion of cholesterol into the feces.

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This study exanimed the microbial transformation of carbazole (CZ) by an isolated bacterium that can use CZ as a sole carbon and nitrogen source. The strain identified as Pseudomonas stutzeri produced a large amount of anthranilic acid (AA) from CZ in the medium containing a nonionic surfactant. In dialysis culture using ion-exchange resin, 7.9g/liter (58mM) of AA was accumulated from 15g/liter (90mM) of CZ and the molar yield of AA reached about 64%.

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The substrate specificity of Achromobacter protease I (API) was examined for S-2-aminoethyl(AE)cysteinyl bonds in Bz-AEC-OMe/OEt, Bz-AEC-NH₂, and AE-insulin B chain. The protease hydrolyzed all of the tested AE-cysteinyl bonds at the same rate as that of lysyl bonds. Kinetic parameters were estimated for this hydrolysis reaction.

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The 4-hydroxycinnamate decarboxylase gene (pofK gene) was cloned from Klebsiella oxytoca, an epiphytic bacterium able to decarboxylate hydroxycinnamic acids to styrene derivatives, in Escherichia coli JM109. Colonies of the enzyme activity-positive transformants were screened by a selection assay combined with an antifungal test using Cladosporium herbarum IHU9262 as the bio-indicator. Two positive transformants constitutively producing 4-hydroxycinnamate decarboxylase were obtained. One of the transformants had a recombinant plasmid designated as pTCD100 in which a 9.6kb HindIII segment carrying pofK gene was contained. As the expression of the pofK gene in K. oxytoca was substrate-inducible, it was most likely that the pofK gene expression in E. coli cells was free from any regulation by a pofK gene repressor postulated in K. oxytoca cells. The decarboxylase synthesized in E. coli cells showed almost the same specific activity as that of K. oxytoca induced by the substrate.

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Teasterone 3-myristate as a new type of brassinosteroid derivative was found in lily anthers. Esterification only occurs with the hydroxyl group at C3. There is no endogenous esterified derivative of typhasterol, castasterone, or brassinolide in the lily tissues.

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Heinz body hemolysis factors were isolated from boiled onion extracts and characterized as three novel sulfur-containing compounds : sodium trans-1-propenylthiosulfate, sodium cis-1-propenylthiosulfate, sodium n-propylthiosulfate.

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Four facultative anaerobes were isolated from soil as producers of 3-methylaspartate ammonia-lyase (MAL). They were identified as Citrobacter sp. No. 0504, Proteus sp. No. 0601, Escherichia coli No. 1002, and Enterobacter sp. No. 1202. The enzyme activities were induced when the strains were cultivated anaerobically or statically in the presence of (S)-glutamic acid or (2S, 3S)-3-methylaspartic acid. Using cell-free extracts of the isolates, several 3-substituted (S)-aspartic acid derivatives such as (2S, 3S)-3-methylaspartic acid, (2S, 3S)-3-ethylaspartic acid, and (2R, 3S)-3-chloroaspartic acid were synthesized in optically pure form from mesaconic acid, ethylfumaric acid, and chlorofumaric acid, respectively.

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