5XAM

Crystal structure of SecDF in I form at 4 A resolution

Summary for 5XAM

• Entry DOI: 10.2210/pdb5xam/pdb
• Related: 3AQP 5XAN 5XAP
• Descriptor: Protein translocase subunit SecD (1 entity in total)
• Functional Keywords: membrane protein, alfa helical, sec translocon
• Biological source: Deinococcus radiodurans str. R1
• Total number of polymer chains: 2
• Total formula weight: 161306.06

Authors

Tsukazaki, T.,Tanaka, Y.,Furukwa, A. (deposition date: 2017-03-14, release date: 2017-05-17, Last modification date: 2023-11-22)

Primary citation

Furukawa, A.,Yoshikaie, K.,Mori, T.,Mori, H.,Morimoto, Y.V.,Sugano, Y.,Iwaki, S.,Minamino, T.,Sugita, Y.,Tanaka, Y.,Tsukazaki, T.
Tunnel Formation Inferred from the I-Form Structures of the Proton-Driven Protein Secretion Motor SecDF
Cell Rep, 19:895-901, 2017

PubMed Abstract: Protein secretion mediated by SecYEG translocon and SecA ATPase is enhanced by membrane-embedded SecDF by using proton motive force. A previous structural study of SecDF indicated that it comprises 12 transmembrane helices that can conduct protons and three periplasmic domains, which form at least two characterized transition states, termed the F and I forms. We report the structures of full-length SecDF in I form at 2.6- to 2.8-Å resolution. The structures revealed that SecDF in I form can generate a tunnel that penetrates the transmembrane region and functions as a proton pathway regulated by a conserved Asp residue of the transmembrane region. In one crystal structure, periplasmic cavity interacts with a molecule, potentially polyethylene glycol, which may mimic a substrate peptide. This study provides structural insights into the Sec protein translocation that allows future analyses to develop a more detailed working model for SecDF.

PubMed: 28467902
DOI: 10.1016/j.celrep.2017.04.030

Experimental method

X-RAY DIFFRACTION (4 Å)