6 Structure basis of the unidirectional catalysis of long chain fatty acyl - CoA synthetase . - Toward the vectorial movement across the membrane

Due to the biological importance of long chain fatty acyl-CoA synthetase (ACSL), ACSL has been studied extensively in the past quarter century. ACSL is a ubiquitous enzyme from bacteria to mammal, and its product, long chain fatty acyl-CoA, is well known to be utilized for the energy metabolism. Furthermore ACSL participates in the cellular uptake of the exogenous Correspondence/Reprint request: Dr. Hideo Ago, Structural Biophysics Laboratory, RIKEN SPring-8 Center Harima Institute, 1-1-1Kouto, Sayo, Hyogo 679-5148, Japan. E-mail: [email protected] Hideo Ago & Masashi Miyano 96 fatty acids. The unique catalytic mechanism, by which the fatty acyl-CoA as the final product is formed unidirectionally via the stable intermediate fatty acylAMP, is behind the biological functions of ACSL. In this manuscript, the unique catalytic mechanism is reviewed with respect to 3-dimentional structure of ACSL.