Patent ID: 7595175
Filing Date: 2009-09-29
Classification: C12N,C12P

Abstract:
1. An isolated nucleic acid encoding a polyketide synthase (PKS) enzyme complex including an altered acyltransferase (AT) domain, wherein said AT domain has been altered to substitute selectively fewer than 9 amino acid residues of the AT domain with a different amino acid residue, the substituted residue(s) consisting of one or more residues of one or more motifs which are present in the active site pocket of the AT domain and which influence the substrate specificity of the AT domain, at least one substitution affecting the substrate specificity, wherein said substituted residue(s) consists of: (a) all or part of the four-residue sequence corresponding to the YASH motif (SEQ ID NO: 114) of the AT domain of the first module of DEBS (6-deoxyerythronolide B synthase); and, optionally, one or more selected from: (b) the residue that is immediately downstream of said four-residue sequence corresponding to the YASH motif of the AT domain of the first module of DEBS; (c) the residue that is immediately downstream of the GHS motif; (d) the residue that is three residues downstream of the GQG motif; and (e) the residue that is four residues downstream of the conserved arginine residue as found at position 144 of SEQ ID NO:26, wherein the SEQ ID NO:26 is the AT domain of the first module of DEBS.