6H3J

Structural snapshots of the Type 9 protein translocon Plug-complex

6H3J の概要

• エントリーDOI: 10.2210/pdb6h3j/pdb
• EMDBエントリー: 0134
• 分子名称: Protein involved in gliding motility SprA, Peptidyl-prolyl cis-trans isomerase, Plug (3 entities in total)
• 機能のキーワード: type 9 secretion system type ix secretion system t9s folded protein secretion outer membrane protein, protein transport
• 由来する生物種: Flavobacterium johnsoniae (Cytophaga johnsonae); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 338073.83

構造登録者

Deme, J.C.,Lea, S.M. (登録日: 2018-07-18, 公開日: 2018-11-07, 最終更新日: 2024-05-15)

主引用文献

Lauber, F.,Deme, J.C.,Lea, S.M.,Berks, B.C.
Type 9 secretion system structures reveal a new protein transport mechanism.
Nature, 564:77-82, 2018

PubMed Abstract: The type 9 secretion system (T9SS) is the protein export pathway of bacteria of the Gram-negative Fibrobacteres-Chlorobi-Bacteroidetes superphylum and is an essential determinant of pathogenicity in severe periodontal disease. The central element of the T9SS is a so-far uncharacterized protein-conducting translocon located in the bacterial outer membrane. Here, using cryo-electron microscopy, we provide structural evidence that the translocon is the T9SS protein SprA. SprA forms an extremely large (36-strand) single polypeptide transmembrane β-barrel. The barrel pore is capped on the extracellular end, but has a lateral opening to the external membrane surface. Structures of SprA bound to different components of the T9SS show that partner proteins control access to the lateral opening and to the periplasmic end of the pore. Our results identify a protein transporter with a distinctive architecture that uses an alternating access mechanism in which the two ends of the protein-conducting channel are open at different times.

PubMed: 30405243
DOI: 10.1038/s41586-018-0693-y

実験手法

ELECTRON MICROSCOPY (3.7 Å)