6O14

Crystal structure of the Aquifex aeolicus Wzt Carbohydrate Binding Domain

Summary for 6O14

• Entry DOI: 10.2210/pdb6o14/pdb
• Related: 2R5O 5HNO 6AN7
• Descriptor: ABC transporter, GLYCEROL (3 entities in total)
• Functional Keywords: abc transporter, wzt, wzm, o antigen, carbohydrate binding domain, membrane protein
• Biological source: Aquifex aeolicus VF5
• Total number of polymer chains: 2
• Total formula weight: 35587.07

Authors

Bi, Y.,Zimmer, J. (deposition date: 2019-02-17, release date: 2020-01-15, Last modification date: 2023-10-11)

Primary citation

Bi, Y.,Zimmer, J.
Structure and Ligand-Binding Properties of the O Antigen ABC Transporter Carbohydrate-Binding Domain.
Structure, 28:252-, 2020

PubMed Abstract: A hallmark of Gram-negative bacteria is an asymmetric outer membrane containing lipopolysaccharides (LPSs) in the extracellular leaflet. LPS molecules consist of lipid A, which is connected to the inner and outer core oligosaccharides. This LPS core structure is extended in the periplasm by the O antigen, a variable and serotype-defining polysaccharide. In the ABC transporter-dependent LPS biosynthesis pathway, the WzmWzt transporter secretes the complete O antigen across the inner membrane for ligation to the LPS core. In some O antigen transporters, the nucleotide-binding domain of Wzt is fused C-terminally to a carbohydrate-binding domain (CBD) that interacts with the O antigen chain. Here, we present the crystal structure of the Aquifex aeolicus CBD that reveals a conserved flat and a variable twisted jelly-roll surface. The CBD dimer is stabilized by mutual β strand exchange. Microbial glycan array binding studies with the isolated CBD provide insights into its interaction with complex carbohydrates.

PubMed: 31879128
DOI: 10.1016/j.str.2019.11.020

Experimental method

X-RAY DIFFRACTION (2.65 Å)