In vivo structures of an intact type VI secretion system revealed by electron cryotomography.

ABSTRACT: The type VI secretion system (T6SS) is a versatile molecular weapon used by many bacteria against eukaryotic hosts or prokaryotic competitors. It consists of a cytoplasmic bacteriophage tail-like structure anchored in the bacterial cell envelope via a cytoplasmic baseplate and a periplasmic membrane complex. Rapid contraction of the sheath in the bacteriophage tail-like structure propels an inner tube/spike complex through the target cell envelope to deliver effectors. While structures of purified contracted sheath and purified membrane complex have been solved, because sheaths contract upon cell lysis and purification, no structure is available for the extended sheath. Structural information about the baseplate is also lacking. Here, we use electron cryotomography to directly visualize in

SUBMITTER: Chang YW 

PROVIDER: S-EPMC5494534 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature