Structure-based working model of SecDF, a proton-driven bacterial protein translocation factor
Year: 2018
Type: review
Abstract: The bacterial membrane protein SecDF enhances protein translocation across the membrane driven by the complex of SecA ATPase and SecYEG. Many newly synthesized proteins in the cytoplasm are programmed to be translocated to the periplasm via the narrow channel that is formed in the center of SecYEG. During the protein-translocation process, SecDF is proposed to undergo repeated conformational transitions to pull out the precursor protein from the SecYEG channel into the periplasm. Once SecDF captures the precursor protein on the periplasmic surface, SecDF can complete protein translocation even if SecA function is inactivated by ATP depletion, implying that SecDF is a protein-translocation motor that works independent of SecA. Structural and functional analyses of SecDF in 2011 suggested that SecDF utilizes the proton gradient and interacts with precursor protein in the flexible periplasmic region. The crystal structures of SecDF in different states at more than 3Å resolution were reported in 2017 and 2018, which further improved our understanding of the dynamic molecular mechanisms of SecDF. This review summarizes recent structural studies of SecDF.
Source: FEMS Microbiology Letters
Author: Tomoya Tsukazaki
Institution: Nara Institute of Science and Technology
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,297
Funders: Ministry of Education, Culture, Sports, Science and Technology, Mochida Memorial Foundation for Medical and Pharmaceutical Research, Japan Society for the Promotion of Science, Noguchi Memorial Institute for Medical Research, University of Ghana, Precursory Research for Embryonic Science and Technology
Awards: Elucidation of the process of membrane protein insrtion and folding., G1705886493, G1952478032, G3139081177, Structural basis and mechanism of Sec holo translocon complex, Dynamism of a proton-driven protein translocation motor., Structural basis for membrane protein integration, G7673548920, G8218010530, G8462447346
OpenAlex ID: W2802451127