SPI-1 type 3 secretion system secretin forms a ring-shaped multimeric structure which is used to inject bacterial effector proteins into eukaryotic host cells [1-3]. It consists of several N-terminal short domains and a C-terminal secretin domain (Pfam:PF00263). This entry represents the N-terminal N0 domain.

1: Three-dimensional model of Salmonella's needle complex at subnanometer resolution. Schraidt O, Marlovits TC; Science. 2011;331:1192-1195. PMID:21385715

2: A conserved structural motif mediates formation of the periplasmic rings in the type III secretion system. Spreter T, Yip CK, Sanowar S, Andre I, Kimbrough TG, Vuckovic M, Pfuetzner RA, Deng W, Yu AC, Finlay BB, Baker D, Miller SI, Strynadka NC; Nat Struct Mol Biol. 2009;16:468-476. PMID:19396170

3: A refined model of the prototypical Salmonella SPI-1 T3SS basal body reveals the molecular basis for its assembly. Bergeron JR, Worrall LJ, Sgourakis NG, DiMaio F, Pfuetzner RA, Felise HB, Vuckovic M, Yu AC, Miller SI, Baker D, Strynadka NC; PLoS Pathog. 2013;9:e1003307. PMID:23633951

4: Near-atomic-resolution cryo-EM analysis of the Salmonella T3S injectisome basal body. Worrall LJ, Hong C, Vuckovic M, Deng W, Bergeron JRC, Majewski DD, Huang RK, Spreter T, Finlay BB, Yu Z, Strynadka NCJ; Nature. 2016;540:597-601. PMID:27974800

5: T3S injectisome needle complex structures in four distinct states reveal the basis of membrane coupling and assembly. Hu J, Worrall LJ, Vuckovic M, Hong C, Deng W, Atkinson CE, Brett Finlay B, Yu Z, Strynadka NCJ; Nat Microbiol. 2019;4:2010-2019. PMID:31427728