Structure of the cytoplasmic domain of TcpE, the inner membrane core protein required for assembly of the Vibrio cholerae toxin-coregulated pilus

The crystal structure of the N-terminal domain of V. cholerae TcpE was determined to 1.88 Å resolution revealing a monomeric six-helix bundle that is conserved in GspF family homologs. A conserved hydrophobic groove at the bottom of this domain may interact with cytoplasmic components of the pilus assembly apparatus.