ENZYME ACTIVITIES IN CELL-FREE EXTRACTS OF SHIKONIN-PRODUCING LITHOSPERMUM ERYTHRORHIZON CELL SUSPENSION CULTURES

Article abstract of DOI:10.1016/S0031-9422(00)82262-1

Lithospermum erythrorhizon cell cultures excrete large quantities of naphthoquinone pigments, viz. shikonin derivatives, which have made enzymatic studies impossible so far.This paper describes methods for the removal of shikonin derivatives from the cells with liquid paraffin during culture growth and for the preparation of active enzyme extracts.Chorismate mutase and shikimate dehydrogenase activities were used as indicators for the preparation of active extracts.The efficacy of the methods developed was proved by the demonstration of the enzymatic formation of m-geranyl-p-hydroxybenzoic acid from geranylpyrophosphate and p-hydroxybenzoic acid in cell-free extracts of L. erythrorhizon cultures, the first detection of a key enzyme of shikonin biosynthesis.Key Word Index - Lithospermum erythrorhizon; Boraginaceae; cell culture; naphthoquinones; shikonin; chorismate mutase; shikimate dehydrogenase.