Microscopic Examination of Parathion Activating Microsomes from American Cockroach1 Fat Body23

Abstract

Periplaneta americana (L.) fat body homogenates were separated into 3 fractions by differential centrifugation. The debris fraction (390 gmax for 10 min) supernatant was fractioned to 2 other fractions designated as the mitochondrial (650 gmax for 120 min) and the microsomal (55,610 gmax for 45 min) fractions. The mitochrondrial pellet contained 92% of the cytochrome oxidase and 25% of the parathion activation activity in the debris supernatant. The microsomal fraction contained 17% of the cytochrome oxidase and 77% of the parathion activation activity of the debris supernatant. The microsomal fraction appeared to be derived from the cellular endoplasmic reticulum.