Towards a structural comprehension of bacterial type VI secretion systems: characterization of the TssJ-TssM complex of an Escherichia coli pathovar.

ABSTRACT: Type VI secretion systems (T6SS) are trans-envelope machines dedicated to the secretion of virulence factors into eukaryotic or prokaryotic cells, therefore required for pathogenesis and/or for competition towards neighboring bacteria. The T6SS apparatus resembles the injection device of bacteriophage T4, and is anchored to the cell envelope through a membrane complex. This membrane complex is composed of the TssL, TssM and TagL inner membrane anchored proteins and of the TssJ outer membrane lipoprotein. Here, we report the crystal structure of the enteroaggregative Escherichia coli Sci1 TssJ lipoprotein, a two four-stranded β-sheets protein that exhibits a transthyretin fold with an additional α-helical domain and a protruding loop. We showed that TssJ contacts TssM through this loop sinc

SUBMITTER: Felisberto-Rodrigues C 

PROVIDER: S-EPMC3213119 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature