A dodecameric ring-like structure of the N0 domain of the type II secretin from enterotoxigenic Escherichia coli.

ABSTRACT: In many bacteria, secretins from the type II secretion system (T2SS) function as outer membrane gated channels that enable passage of folded proteins from the periplasm into the extracellular milieu. Cryo-electron microscopy of the T2SS secretin GspD revealed previously the dodecameric cylindrical architecture of secretins, and crystal structures of periplasmic secretin domains showed a modular domain organization. However, no high-resolution experimental data has as yet been provided about how the entire T2SS secretin or its domains are organized in a cylindrical fashion. Here we present a crystal structure of the N0 domain of the T2SS secretin GspD from enterotoxigenic Escherichia coli containing a helix with 12 subunits per turn. The helix has an outer diameter of ∼125Å and a pitch of o

SUBMITTER: Korotkov KV 

PROVIDER: S-EPMC3769495 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature