An enzyme with an acyl transfer function has an amino acid sequence identical to a SEQ ID NO:1, which is capable of acylation modification for macrolactins, filipins macrolides, chloramphenicol, and glycosylated piericidin A. An application of an acyltransferase of the present invention is to bind an acyl group of an acyl donor to macrolide compounds, chloramphenicol and glycosylated piericidins. The enzyme with the acyl transfer function can improve pharmacological activity of the macrolide compounds through acylation reaction of macrolactins, thereby improving bioavailability, enhancing efficacy, and reducing toxic as well as side effects, which provides a new strategy for the drug development of macrolide compounds.