7ZOA

cryo-EM structure of CGT ABC transporter in presence of CBG substrate

7ZOA の概要

• エントリーDOI: 10.2210/pdb7zoa/pdb
• EMDBエントリー: 14844 14845
• 分子名称: Beta-(1-->2)glucan export ATP-binding/permease protein NdvA, Cyclooctadecakis-(1-2)-(beta-D-glucopyranose) (2 entities in total)
• 機能のキーワード: cyclic-beta-glucan, abc transporter, cgt, brucella, sugar binding protein
• 由来する生物種: Brucella abortus 2308
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 134992.38

構造登録者

Jaroslaw, S.,Dong, C.N.,Frank, L.,Na, W.,Renato, Z.,Seunho, J.,Henning, S.,Christoph, D. (登録日: 2022-04-24, 公開日: 2022-12-07, 最終更新日: 2024-07-24)

主引用文献

Sedzicki, J.,Ni, D.,Lehmann, F.,Wu, N.,Zenobi, R.,Jung, S.,Stahlberg, H.,Dehio, C.
Mechanism of cyclic beta-glucan export by ABC transporter Cgt of Brucella.
Nat.Struct.Mol.Biol., 29:1170-1177, 2022

PubMed Abstract: Polysaccharides play critical roles in bacteria, including the formation of protective capsules and biofilms and establishing specific host cell interactions. Their transport across membranes is often mediated by ATP-binding cassette (ABC) transporters, which utilize ATP to translocate diverse molecules. Cyclic β-glucans (CβGs) are critical for host interaction of the Rhizobiales, including the zoonotic pathogen Brucella. CβGs are exported into the periplasmic space by the cyclic glucan transporter (Cgt). The interaction of an ABC transporter with a polysaccharide substrate has not been visualized so far. Here we use single-particle cryoelectron microscopy to elucidate the structures of Cgt from Brucella abortus in four conformational states. The substrate-bound structure reveals an unusual binding pocket at the height of the cytoplasmic leaflet, whereas ADP-vanadate models hint at an alternative mechanism of substrate release. Our work provides insights into the translocation of large, heterogeneous substrates and sheds light on protein-polysaccharide interactions in general.

PubMed: 36456825
DOI: 10.1038/s41594-022-00868-7

実験手法

ELECTRON MICROSCOPY (4 Å)