The present invention related to a method of producing polypeptides in transformed host cells by expressing a precursor molecule of the desired polypeptide which are to be acylated in a subsequent in vitro step. The invention is also related to DNA-sequences, vectors and transformed host cells for use in the claimed method. Further, the present invention is related to certain precursors of the desired polypeptides and certain acylation methods. The invention provides a method for making polypeptides being preferentially acylated in certain lysine .epsilon.-amino groups.