Studies on long chaincis‐ andTrans‐acyl‐CoA esters and acyl‐CoA dehydrogenase from rat heart mitochondria

Abstract

The β-oxidation of long chain fatty acids was investigated in a preparation of rat heart mitochondria. The acyl-CoA esters of thecis andtrans isomers of Δ9-hexadecenoic, Δ9-octadecenoic, Δ11-eicosenoic, and Δ13-docosenoic acids were prepared. Rates of the acyl-CoA reaction were determined with an extract from rat heart mitochondria. The apparent Michaelis constant (K_m) and maximum velocity (V_max) were calculated for each substrate. In general, apparent V_max values decreased with increasing chain length of the monoenoic substrates. Reduced activity of acyl-CoA dehydrogenase with long chain acyl-CoA esters could have contributed to accumulation of lipids in hearts of rats fed diets containing long chain fatty acids.