Required for the synthesis of an acyl-HSL autoinducer that binds to YukR and which is involved in the regulation of motility and morphology. a fatty acyl-[ACP] + S-adenosyl-L-methionine = an N-acyl-L-homoserine lactone + H(+) + holo-[ACP] + S-methyl-5'-thioadenosine Belongs to the autoinducer synthase family.