6MGC

Escherichia coli KpsC, N-terminal domain

Summary for 6MGC

• Entry DOI: 10.2210/pdb6mgc/pdb
• Descriptor: Capsule polysaccharide export protein KpsC, CYTIDINE-5'-MONOPHOSPHATE, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: glycosyltransferase, cytosine monophosphate, transferase
• Biological source: Escherichia coli O1:K1 / APEC
• Total number of polymer chains: 1
• Total formula weight: 40681.67

Authors

Doyle, L.,Mallette, E.,Kimber, M.S. (deposition date: 2018-09-13, release date: 2019-03-27, Last modification date: 2024-03-13)

Primary citation

Doyle, L.,Ovchinnikova, O.G.,Myler, K.,Mallette, E.,Huang, B.S.,Lowary, T.L.,Kimber, M.S.,Whitfield, C.
Biosynthesis of a conserved glycolipid anchor for Gram-negative bacterial capsules.
Nat.Chem.Biol., 15:632-640, 2019

PubMed Abstract: Several important Gram-negative bacterial pathogens possess surface capsular layers composed of hypervariable long-chain polysaccharides linked via a conserved 3-deoxy-β-D-manno-oct-2-ulosonic acid (β-Kdo) oligosaccharide to a phosphatidylglycerol residue. The pathway for synthesis of the terminal glycolipid was elucidated by determining the structures of reaction intermediates. In Escherichia coli, KpsS transfers a single Kdo residue to phosphatidylglycerol; this primer is extended using a single enzyme (KpsC), possessing two cytidine 5'-monophosphate (CMP)-Kdo-dependent glycosyltransferase catalytic centers with different linkage specificities. The structure of the N-terminal β-(2→4) Kdo transferase from KpsC reveals two α/β domains, supplemented by several helices. The N-terminal Rossmann-like domain, typically responsible for acceptor binding, is severely reduced in size compared with canonical GT-B folds in glycosyltransferases. The similar structure of the C-terminal β-(2→7) Kdo transferase indicates a past gene duplication event. Both Kdo transferases have a narrow active site tunnel, lined with key residues shared with GT99 β-Kdo transferases. This enzyme provides the prototype for the GT107 family.

PubMed: 31036922
DOI: 10.1038/s41589-019-0276-8

Experimental method

X-RAY DIFFRACTION (1.35 Å)