PHOSPHOLIPASE B OF BARLEY MALT .2. STUDIES ON FUNCTION OF ENZYME

During the reaction of phospholipase B of barley malt, lysolecithin is temporarily formed. The fatty acid is split off indiscriminately from the α- or β-position. p-chlormercuribenzoate inhibited the enzyme as well as taurocholate and desoxycholate, the latter less intensively, however. Neither did calcium ions nor ethylen-diamintetra-acetate have any influence. There were no indications for accumulation or rapid decomposition of lysolecithin. Therefore it seems probable that the phospholipase-preparation represents a phospholipid-diacyl-hydrolase, which splits off the fatty acids of the lecithin molecule in two steps. The phospholipase-preparation contained a lipid fraction which is necessary for the development of full activity. The main constituents of these lipids are triglycerides and in smaller amounts, mono-, diglycerides, fatty acids, β-sitosterin and phospholipids. Higher fatty acids were able to take over the function of the lipid fraction in the phospholipase-B action. © 1969 Springer-Verlag.