5AWW

Precise Resting State of Thermus thermophilus SecYEG

Summary for 5AWW

• Entry DOI: 10.2210/pdb5aww/pdb
• Related: 5CH4
• Descriptor: Protein translocase subunit SecY, Protein translocase subunit SecE, Putative preprotein translocase, SecG subunit, ... (5 entities in total)
• Functional Keywords: translocon, membrane protein, protein transport-immune system complex, protein transport/immune system
• Biological source: Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579); More
• Total number of polymer chains: 3
• Total formula weight: 67895.37

Authors

Tanaka, Y.,Sugano, Y.,Takemoto, M.,Kusakizako, T.,Kumazaki, K.,Ishitani, R.,Nureki, O.,Tsukazaki, T. (deposition date: 2015-07-10, release date: 2015-11-25, Last modification date: 2023-11-08)

Primary citation

Tanaka, Y.,Sugano, Y.,Takemoto, M.,Mori, T.,Furukawa, A.,Kusakizako, T.,Kumazaki, K.,Kashima, A.,Ishitani, R.,Sugita, Y.,Nureki, O.,Tsukazaki, T.
Crystal Structures of SecYEG in Lipidic Cubic Phase Elucidate a Precise Resting and a Peptide-Bound State.
Cell Rep, 13:1561-1568, 2015

PubMed Abstract: The bacterial SecYEG translocon functions as a conserved protein-conducting channel. Conformational transitions of SecYEG allow protein translocation across the membrane without perturbation of membrane permeability. Here, we report the crystal structures of intact SecYEG at 2.7-Å resolution and of peptide-bound SecYEG at 3.6-Å resolution. The higher-resolution structure revealed that the cytoplasmic loop of SecG covers the hourglass-shaped channel, which was confirmed to also occur in the membrane by disulfide bond formation analysis and molecular dynamics simulation. The cytoplasmic loop may be involved in protein translocation. In addition, the previously unknown peptide-bound crystal structure of SecYEG implies that interactions between the cytoplasmic side of SecY and signal peptides are related to lateral gate opening at the first step of protein translocation. These SecYEG structures therefore provide a number of structural insights into the Sec machinery for further study.

PubMed: 26586438
DOI: 10.1016/j.celrep.2015.10.025

Experimental method

X-RAY DIFFRACTION (2.724 Å)