Localized Protein Interaction Surfaces on the EntB Carrier Protein Revealed by Combinatorial Mutagenesis and Selection

摘要

Carrier protein domains(80 to 100 residues in length)are central to the polyketide synthase(PKS)and nonribosomal peptide synthetase(NRPS)enzymatic assembly lines that produce many metabolites of medicinal interest.Because substrates for biosyn-thetic operations are presented on carrier proteins as covalently attached thioesters(through a 4'-phosphopantetheine cofactor),a detailed understanding of protein-protein interactions between carrier proteins and other domains is required for reprogramming of NRPS/PKS machinery.