Required for the synthesis of OHHL (N-(3-oxohexanoyl)-L-homoserine lactone), an autoinducer molecule which binds to CarR and thus acts in the control of the biosynthesis of carbapenem antibiotics. 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.