title: Hybrid nonribosomal peptide-polyketide interfaces in epothilone biosynthesis: minimal requirements at N and C termini of EpoB for elongation.
abstract: Epothilone (Epo) D, an antitumor agent currently in clinical trials, is a hybrid natural product produced by the combined action of nonribosomal peptide synthetases (NRPS) and polyketide synthases (PKS). In the epothilone biosynthetic pathway, EpoB, a 165 kDa NRPS is inserted into an otherwise entirely PKS assembly line, forming two hybrid NRPS-PKS interfaces. In light of the terminal linker effect previously identified in PKS, the N- and C-terminal sequences of EpoB were examined for their roles in propagating the incipient natural product. Eight amino acid residues at EpoB C terminus, in which six are positively charged, were found to be a key component of the C-terminal linker effect. A minimal sequence of 56 residues at EpoB N terminus was required for elongating the acetyl group from the acyl carrier protein (ACP) of EpoA to form methylthiazolyl-S-EpoB.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Sylvie
authors.initials: S
authors.lastname: Garneau
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Walsh
mesh_terms: D000213:Acyl Carrier Protein / Q000235:genetics; D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism; D001483:Base Sequence; D034261:Epothilones / Q000096:biosynthesis* / Q000737:chemistry / Q000145:classification / Q000235:genetics; D006822:Hybrid Cells / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010441:Peptide Chain Elongation, Translational; D010453:Peptide Synthases / Q000096:biosynthesis* / Q000378:metabolism; D048630:Polyketide Synthases / Q000096:biosynthesis* / Q000378:metabolism; D017384:Sequence Deletion
chemical_list: D000213:Acyl Carrier Protein; D000970:Antineoplastic Agents; D034261:Epothilones; D048630:Polyketide Synthases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase; C093788:epothilone B