6V0C

Lipophilic Envelope-spanning Tunnel B (LetB), Model 1

6V0C の概要

• エントリーDOI: 10.2210/pdb6v0c/pdb
• EMDBエントリー: 20993
• 分子名称: Intermembrane transport protein YebT (1 entity in total)
• 機能のキーワード: lipid transport, bacterial cell envelope, mce, yebt
• 由来する生物種: Escherichia coli (strain K12)
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 538464.19

構造登録者

Isom, G.L.,Coudray, N.,MacRae, M.R.,McManus, C.T.,Ekiert, D.C.,Bhabha, G. (登録日: 2019-11-18, 公開日: 2020-05-06, 最終更新日: 2024-03-06)

主引用文献

Isom, G.L.,Coudray, N.,MacRae, M.R.,McManus, C.T.,Ekiert, D.C.,Bhabha, G.
LetB Structure Reveals a Tunnel for Lipid Transport across the Bacterial Envelope.
Cell, 181:653-664.e19, 2020

PubMed Abstract: Gram-negative bacteria are surrounded by an outer membrane composed of phospholipids and lipopolysaccharide, which acts as a barrier and contributes to antibiotic resistance. The systems that mediate phospholipid trafficking across the periplasm, such as MCE (Mammalian Cell Entry) transporters, have not been well characterized. Our ~3.5 Å cryo-EM structure of the E. coli MCE protein LetB reveals an ~0.6 megadalton complex that consists of seven stacked rings, with a central hydrophobic tunnel sufficiently long to span the periplasm. Lipids bind inside the tunnel, suggesting that it functions as a pathway for lipid transport. Cryo-EM structures in the open and closed states reveal a dynamic tunnel lining, with implications for gating or substrate translocation. Our results support a model in which LetB establishes a physical link between the two membranes and creates a hydrophobic pathway for the translocation of lipids across the periplasm.

PubMed: 32359438
DOI: 10.1016/j.cell.2020.03.030

実験手法

ELECTRON MICROSCOPY (3.46 Å)