Type III secretion system, PrgH/EprH / Type III secretion system lipoprotein HrcJ/YscJ / Type III secretion system, PrgH/EprH-like / Type III secretion system protein PrgH-EprH (PrgH) / Lipoprotein YscJ/Flagellar M-ring protein / Secretory protein of YscJ/FliF family / Flagellar M-ring , N-terminal / AMP-binding enzyme, C-terminal domain superfamily / Prokaryotic membrane lipoprotein lipid attachment site profile. 類似検索 - ドメイン・相同性
ジャーナル: Nature / 年: 2016 タイトル: Near-atomic-resolution cryo-EM analysis of the Salmonella T3S injectisome basal body. 著者: L J Worrall / C Hong / M Vuckovic / W Deng / J R C Bergeron / D D Majewski / R K Huang / T Spreter / B B Finlay / Z Yu / N C J Strynadka / 要旨: The type III secretion (T3S) injectisome is a specialized protein nanomachine that is critical for the pathogenicity of many Gram-negative bacteria, including purveyors of plague, typhoid fever, ...The type III secretion (T3S) injectisome is a specialized protein nanomachine that is critical for the pathogenicity of many Gram-negative bacteria, including purveyors of plague, typhoid fever, whooping cough, sexually transmitted infections and major nosocomial infections. This syringe-shaped 3.5-MDa macromolecular assembly spans both bacterial membranes and that of the infected host cell. The internal channel formed by the injectisome allows for the direct delivery of partially unfolded virulence effectors into the host cytoplasm. The structural foundation of the injectisome is the basal body, a molecular lock-nut structure composed predominantly of three proteins that form highly oligomerized concentric rings spanning the inner and outer membranes. Here we present the structure of the prototypical Salmonella enterica serovar Typhimurium pathogenicity island 1 basal body, determined using single-particle cryo-electron microscopy, with the inner-membrane-ring and outer-membrane-ring oligomers defined at 4.3 Å and 3.6 Å resolution, respectively. This work presents the first, to our knowledge, high-resolution structural characterization of the major components of the basal body in the assembled state, including that of the widespread class of outer-membrane portals known as secretins.