sentences:  However, these different enzymes share the need to stabilize an enolate anion intermediate derived from an acyl-CoA substrate.This is accomplished by two structurally conserved peptidic NH groups that provide hydrogen bonds to the carbonyl moieties of the acyl-CoA substrates and form an "oxyanion hole".The CoA thioester derivatives bind in a characteristic hooked shape and a conserved tunnel binds the pantetheine group of CoA, which links the 3'-phosphate ADP binding site to the site of reaction.