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A correlation existed between the productivity of sclerin (SCL) and formation of sclerotia or dark pigmentation of old hyphae in Sclerotinia libertiana Fuckel and S. sclerotiorum de Bary. SCL stimulated the activities of phenoloxidase and peroxidase in a mycelial extract of S. libertiana, which appeared to be involved in the maturation and pigmentation of sclerotia. On the other hand, p-aminobenzoic acid (PABA), an inhibitor of phenoloxidase, inhibited the production of both SCL and sclerotia, where assimilation of PABA probably interrupted the biosynthetic process of SCL. When SCL was added at a high concentration, 4×10−3m, to Czapek’s agar medium a strain of S. libertiana which originally formed sclerotia and a strain of S. sclerotiorum which did not form sclerotia but produced melanin-like pigments at the edge of colony formed numerous sclerotium initials, which did not develop normal sclerotia. It was suggested that SCL played a role on induction of sclerotial formation and melanogenesis in these stra...

Changes in the contents and compositions of lipid classes and water-soluble components were examined in maturing soybean seed. At the first stage of seed development, triglyceride formation was very slow, and considerably large quantity of free fatty acids, phosphatidic acid, monoglyceride, and diglyceride were accumulated. At the second stage triglycerides were produced rapidly and the other components decreased. Glycerophosphate also appeared in the maturing seed. These results suggest that Kennedy’s pathway to triglycerides and other side pathway occur in seed. Positional distribution of fatty acids in mono-, di-, and triglycerides was also determined, and synthetic process of glyceride structure was discussed.

A cell-free system for the biosynthesis of l-threo-neopterin, a growth factor for protozoan, Crithidia fasciculata from guanosine-5′-triphosphate (GTP) was obtained from extracts of Serratia indica IFO 3759. This preparation catalyzed the production of a specific pteridine from GTP, which was isolated and characterized as a cyclic phosphate of neopterin (cNP). Among the other products, l-threo-neopterin, as the Crithidia factor, 6-hydroxymethylpterin, and erythro-neopterin were tentatively identified. Requirements for the synthesis of these products include GTP, Mg2+, and disodium phosphate. Fluorescence formation was inhibited by purine nucleotides.When a disodium phosphate was included in the reaction system, cNP and erythro-neopterin were effectively synthesized from GTP. On the other hand, when the phosphate was omitted 6-hydroxymethylpterin was formed.The possible biosynthetic process of l-threo-neopterin was discussed.