Synthesis of diacylglycerols by monoacylglycerol acyltransferase from crop,midgut and fat body tissues of the american cockroach,Periplaneta americana L.

Monoacylglycerol acyltransferase (E.C. 2.3.1 type) activity was determined in the crop, midgut and fat body of adult, male cockroaches. Tissue homogenates were capable of acylating [³H]-glycerol-2-monoolein with palmitic acid. The major product was diacylglycerol although some triacylglycerol was also formed. The greatest rate of acylation was observed in the midgut, but the crop and the fat body also displayed a capacity for acylation of monoacylglycerol. The enzyme activity was dependent on time, protein and substrate concentration. The ability of rac-1-monoolein and 2-monooleyl glyceryl ether to substitute for 2-monoolein as an acyl acceptor, was also demonstrated.