@article {49433,
	title = {Cryo-EM analysis of the T3S injectisome reveals the structure of the needle and open secretin.},
	journal = {Nature Communications},
	volume = {9},
	year = {2018},
	month = {2018 Sep 21},
	pages = {3840},
	abstract = {<p>The bacterial type III secretion system, or injectisome, is a syringe shaped nanomachine essential for the virulence of many disease causing Gram-negative bacteria. At the core of the injectisome structure is the needle complex, a continuous channel formed by the highly oligomerized inner and outer membrane hollow rings and a polymerized helical needle filament which spans through and projects into the infected host cell. Here we present the near-atomic resolution structure of a needle complex from the prototypical Salmonella Typhimurium SPI-1 type III secretion system, with local masking protocols allowing for model building and refinement of the major membrane spanning components of the needle complex\&nbsp;base in addition to an isolated needle filament. This work provides significant insight into injectisome structure and assembly and importantly captures the molecular basis for substrate induced gating in the giant outer membrane secretin portal family.</p>
},
	issn = {2041-1723},
	doi = {10.1038/s41467-018-06298-8},
	author = {Hu, J and Worrall, L J and Hong, C and Vuckovic, M and Atkinson, C E and Caveney, N and Yu, Z and Strynadka, N C J}
}
@article {48128,
	title = {Near-atomic-resolution cryo-EM analysis of the Salmonella T3S injectisome basal body.},
	journal = {Nature},
	year = {2016},
	month = {2016 Dec 14},
	abstract = {<p>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 {\r A} and 3.6 {\r A} 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.</p>
},
	issn = {1476-4687},
	doi = {10.1038/nature20576},
	author = {Worrall, L J and Hong, C and Vuckovic, M and Deng, W and Bergeron, J R C and Majewski, D D and Huang, R K and Spreter, T and Finlay, B B and Yu, Z and Strynadka, N C J}
}
