Unexpected stereoselective exchange of straight-chain fatty acyl-CoA α-protons by human α-methylacyl-CoA racemase 1A (P504S)

Abstract

Alpha-methylacyl-CoA racemase (AMACR; P504S) catalysed exchange of straight-chain fatty acyl-CoA alpha-protons. One alpha-proton was removed in each catalytic cycle, with the pro-S proton preferred. This reaction was most efficient for straight-chain substrates with longer side-chains. 2-Methyldecanoyl-CoA underwent alpha-proton exchange 3x more efficiently (as judged by K(cat)/K(m)) than decanoyl-CoA.