Molecular basis for bacterial N-glycosylation by a soluble HMW1C-like N-glycosyltransferase.

ABSTRACT: Soluble HMW1C-like N-glycosyltransferases (NGTs) catalyze the glycosylation of Asn residues in proteins, a process fundamental for bacterial autoaggregation, adhesion and pathogenicity. However, our understanding of their molecular mechanisms is hindered by the lack of structures of enzymatic complexes. Here, we report structures of binary and ternary NGT complexes of Aggregatibacter aphrophilus NGT (AaNGT), revealing an essential dyad of basic/acidic residues located in the N-terminal all α-domain (AAD) that intimately recognizes the Thr residue within the conserved motif Asn⁰-X⁺¹-Ser/Thr⁺². Poor substrates and inhibitors such as UDP-galactose and UDP-glucose mimetics adopt non-productive conformations, decreasing or impeding catalysis. QM/MM simulations r

SUBMITTER: Piniello B 

PROVIDER: S-EPMC10507012 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature