Long chain fatty acid coenzyme-A synthetase (LC-FACS) participates in the first reaction step of long chain fatty acid degradation. These enzymes act on a wide range of long-chain saturated and unsaturated fatty acids, but the enzymes from different tissues and species show some variation in specificity. For example, the liver enzyme acts on acids from C6 to C20, that from brain shows high activity up to C24, and the enzyme from Thermus thermophilus acts on C12 to C22 fatty acids. LC-FACS catalyses the conversion of long chain fatty acids into fatty-acyl-CoA, creating AMP and pyrophosphate as bi-products. LC-FACS is responsible for physiological regulation of cellular functions, as well as fatty acid degradation.
Defined by 4 residues: THR:A-184GLU:A-328LYS:A-439TRP:A-444