Biochemical Demonstration of the Involvement of Fatty Acyl-CoA Synthetase in Fatty Acid Translocation across the Plasma Membrane*

Fatty acyl-CoA synthetase, the first enzyme of the beta-oxidation pathway, has been proposed to be involved in long chain fatty acid translocation across the plasma membrane of prokaryotic and eukaryotic cells. To test this proposal, we used an in vitro system consisting of Escherichia coli inner (plasma) membrane vesicles containing differing amounts of trapped fatty acyl-CoA synthetase and its substrates CoA and ATP. This system allowed us to …