菌類によるアルカロイドおよび関連物質の生産(第2報)

クラビン型麦角アルカロイドの微生物変換に関する吟味

抄録

The conversions of clavine-type alkaloids have been studied by the use of non-labeled alkaloids and the acetone-treated mycelia of the strains of the Claviceps as well as those of the Aspergillus, Penicillium and others which were productive of clavine-type ergot alkaloids. It was found that agroclavine could be converted to elymoclavine not only by ergot fungi but also by the fungus other than ergot fungi. This finding indicates that the theory presented by authors that elymoclavine is the primary product of the ergot alkaloids has become untenable to some extent. While, it was found that, besides the previous cyclic route, elymoclavine→lysergolI→lysergene→agroclavine→elymoclavine, another biosynthetic route from agroclavine to elymoclavine through lysergene, lysergol and an unestablished alkaloid PS might exist in various fungi on the one hand. This finding indicates that agroclavine rather than elymoclavine will be the primary product of the alkaloids, and that chanoclavine (secaclavine) will be a biosynthetic precursor of agroclavine, and therefore, of the remaining alkaloids. Judging from the data of Stauffacher et al., it was presumed that the reversible reaction, chanoclavine_??_agroclavine, which was found in all of the tested strains would be effected through a certain intermediary compound, possibly iso-chanoclavine-(I), and indeed this intermediary compound would be an obligatory precursor of agroclavine.
The present finding indicates that the conversion reaction, elymoclavine→peptide-type alkaloids, cannot be effected through lysergol, but possibly through 6-methyl-Δ^{8, 9}-ergolene-8-carboxylic acid which was discovered by Kobel et al. The outline of this study was given at the 3 rd International Symposium on “Biochemistry and Physiology of Alkaloids” held in Halle (Saale), June 24_??_27, 1965.