Membrane association of monotopic phosphoglycosyl transferase underpins function

Polyprenol phosphate phosphoglycosyl transferases (PGTs) catalyze the first membrane-committed step in assembly of essential glycoconjugates. Currently there is no structure–function information to describe how monotopic PGTs coordinate the reaction between membrane-embedded and soluble substrates. We describe the structure and mode of membrane association of PglC, a PGT from Campylobacter concisus . The structure reveals a unique architecture, provides mechanistic insight and identifies ligand-binding determinants for PglC and the monotopic PGT superfamily. The structure of a monotopic polyprenol phosphate phosphoglycosyl transferase, PglC, reveals how it interacts with the bacterial membrane and coordinates a reaction between membrane-embedded and soluble substrates during glycoconjugate assembly.