5FA1

The structure of the beta-3-deoxy-D-manno-oct-2-ulosonic acid transferase domain of WbbB

Summary for 5FA1

• Entry DOI: 10.2210/pdb5fa1/pdb
• Related: 5FA0
• Descriptor: Putative N-acetyl glucosaminyl transferase, CYTIDINE-5'-MONOPHOSPHATE (3 entities in total)
• Functional Keywords: lps biosynthesis, glycosyltransferase, transferase
• Biological source: Raoultella terrigena
• Total number of polymer chains: 2
• Total formula weight: 92839.93

Authors

Mallette, E.,Ovchinnikova, O.G.,Whitfield, C.,Kimber, M.S. (deposition date: 2015-12-10, release date: 2016-05-18, Last modification date: 2023-09-27)

Primary citation

Ovchinnikova, O.G.,Mallette, E.,Koizumi, A.,Lowary, T.L.,Kimber, M.S.,Whitfield, C.
Bacterial beta-Kdo glycosyltransferases represent a new glycosyltransferase family (GT99).
Proc. Natl. Acad. Sci. U.S.A., 113:E3120-E3129, 2016

PubMed Abstract: Kdo (3-deoxy-d-manno-oct-2-ulosonic acid) is an eight-carbon sugar mostly confined to Gram-negative bacteria. It is often involved in attaching surface polysaccharides to their lipid anchors. α-Kdo provides a bridge between lipid A and the core oligosaccharide in all bacterial LPSs, whereas an oligosaccharide of β-Kdo residues links "group 2" capsular polysaccharides to (lyso)phosphatidylglycerol. β-Kdo is also found in a small number of other bacterial polysaccharides. The structure and function of the prototypical cytidine monophosphate-Kdo-dependent α-Kdo glycosyltransferase from LPS assembly is well characterized. In contrast, the β-Kdo counterparts were not identified as glycosyltransferase enzymes by bioinformatics tools and were not represented among the 98 currently recognized glycosyltransferase families in the Carbohydrate-Active Enzymes database. We report the crystallographic structure and function of a prototype β-Kdo GT from WbbB, a modular protein participating in LPS O-antigen synthesis in Raoultella terrigena The β-Kdo GT has dual Rossmann-fold motifs typical of GT-B enzymes, but extensive deletions, insertions, and rearrangements result in a unique architecture that makes it a prototype for a new GT family (GT99). The cytidine monophosphate-binding site in the C-terminal α/β domain closely resembles the corresponding site in bacterial sialyltransferases, suggesting an evolutionary connection that is not immediately evident from the overall fold or sequence similarities.

PubMed: 27199480
DOI: 10.1073/pnas.1603146113

Experimental method

X-RAY DIFFRACTION (2.1 Å)