Functions in the bile acid 7alpha-dehydroxylation pathway, which forms secondary bile acids via the 7alpha-dehydroxylation of primary bile acids, and is carried out by intestinal anaerobic bacteria. Catalyzes the initial step in this pathway, i.e. the ATP-dependent thioesterification of primary bile acids with coenzyme A. Is active with C-24 bile acids with free carboxyl groups such as cholate, deoxycholate and chenodeoxycholate. Produces AMP and pyrophosphate in addition to the bile acid-CoA thioester. ATP + cholate + CoA = AMP + choloyl-CoA + diphosphate ATP + CoA + deoxycholate = AMP + deoxycholoyl-CoA + diphosphate ATP + chenodeoxycholate + CoA = AMP + chenodeoxycholoyl-CoA + diphosphate Inhibited by diphosphate. Optimum temperature is 50 degrees Celsius. Lipid metabolism; bile acid biosynthesis. Homodimer. Induced by bile acids such as cholate. Belongs to the ATP-dependent AMP-binding enzyme family.