5HNO

The structure of the kdo-capped saccharide binding subunit of the O-12 specific ABC transporter, Wzt

5HNO の概要

• エントリーDOI: 10.2210/pdb5hno/pdb
• 関連するPDBエントリー: 5HNP
• 分子名称: ABC type transport system putative ATP binding protein, CHLORIDE ION (3 entities in total)
• 機能のキーワード: o antigen export, carbohydrate binding subunit, abc transporter, transport protein
• 由来する生物種: Raoultella terrigena
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 62637.45

構造登録者

Mallette, E.,Mann, E.,Whitfield, C.,Kimber, M.S. (登録日: 2016-01-18, 公開日: 2016-03-09, 最終更新日: 2024-03-06)

主引用文献

Mann, E.,Mallette, E.,Clarke, B.R.,Kimber, M.S.,Whitfield, C.
The Klebsiella pneumoniae O12 ATP-binding Cassette (ABC) Transporter Recognizes the Terminal Residue of Its O-antigen Polysaccharide Substrate.
J.Biol.Chem., 291:9748-9761, 2016

PubMed Abstract: Export of the Escherichia coli serotype O9a O-antigenic polysaccharides (O-PS) involves an ATP-binding cassette (ABC) transporter. The process requires a non-reducing terminal residue, which is recognized by a carbohydrate-binding module (CBM) appended to the C terminus of the nucleotide-binding domain of the transporter. Here, we investigate the process in Klebsiella pneumoniae serotype O12 (and Raoultella terrigena ATCC 33257). The O12 polysaccharide is terminated at the non-reducing end by a β-linked 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) residue. The O12 ABC transporter also binds its cognate O-PS via a CBM, and export is dependent on the presence of the terminal β-Kdo residue. The overall structural architecture of the O12 CBM resembles the O9a prototype, but they share only weak sequence similarity, and the putative binding pocket for the O12 glycan is different. Removal of the CBM abrogated O-PS transport, but export was restored when the CBM was expressed in trans with the mutant CBM-deficient ABC transporter. These results demonstrate that the CBM-mediated substrate-recognition mechanism is evolutionarily conserved and can operate with glycans of widely differing structures.

PubMed: 26934919
DOI: 10.1074/jbc.M116.719344

実験手法

X-RAY DIFFRACTION (1.7 Å)