[Biosynthesis of the components of levorin and fatty acids in the process of Str. levoris cultivation]

The rate of incorporation of the labeled precursors, acetate and propionate, into levorin components and fatty acids was studied. It was shown that within the first 12 hours of cultivation the rate of labeled precursors incorporation into levorin components A2, A3, A0 and A1 was low. In this period the acetate and propionate labeled with respect to the methyl and carboxyl groups mainly incorporated into fatty acids. A higher rate of acetate incorporation as compared to propionate at the beginning of cultivation suggested that acetate was the first link of the chain. At the beginning of the idiophase, i.e. during the period of 36 to 48 hours of cultivation, the rate of incorporation of the carboxyl and methyl groups of the labeled precursors into the levorin components increased. The rate of incorporation of the radioactive precursors into components A2 and A3 markedly increased after 72 hours of cultivation. The maximum rate of incorporation of the carboxyl and methyl groups of acetate and propionate into components A0 and A1 was observed somewhat earlier, i. e. by the 48th hour of cultivation. During the period from 72 to 96 hours of cultivation the incorporation rate of the labeled precursors for components A2 and A3 was constant and then gradually decreased. The radioactivity of components A0 and A1 was constant during the period of 48 to 72 hours of cultivation and then gradually decreased. Beginning from the 24th hour of cultivation the level of 14C-propionate incorporated into all levorin components was higher than that of 14C-acetate incorporation. After 96 hours of cultivation the rate of 2-14C-propionate incorporation into the levorin components was higher than that of 1-14C-propionate incorporation.