Modular polyketide synthases: Investigating intermodular communication using 6 deoxyerythronolide B synthase module 2

A novel variant of 6-deoxyerythronolide B synthase (DEBS) module 2 was constructed to explore the balance between protein–protein-mediated intermodular channeling and intrinsic substrate specificity within DEBS. This construct, termed (N3)Mod2 + TE, was co-incubated with a complementary, donor form of the same module, (N5)Mod2(C2), as well as with a mutant of (N5)Mod2(C2) with an inactive ketosynthase domain, in order to determine the extent of intermediate channeling versus substrate diffusion into the downstream module.

Co-incubation of two engineered variants of 6-deoxyerythronolide B synthase module 2 designed to communicate with one another results in inhibition of catalytic processing of free substrate by the downstream, acceptor module. This inhibition was relieved when a catalytically inactive form of the upstream, donor module was used.Figure optionsDownload as PowerPoint slide