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Full-length Escherichia coli SecA dimerizes in a closed conformation in solution as determined by cryo-electron microscopy.

ABSTRACT: SecA is an obligatory component of the Escherichia coli general secretion pathway. However, the oligomeric structure of SecA and SecA conformational changes during translocation processes are still unclear. Here we obtained the three-dimensional structure of E. coli wild-type full-length SecA in solution by single particle cryo-electron microscopy and determined its oligomeric organization. In this structure, SecA occurs as a dimer in which the two protomers are arranged in an antiparallel mode, with a novel electrostatic interface, and both protomers are in closed conformation. The system developed here may provide a promising technique for studying dynamic structural changes in SecA.

SUBMITTER: Chen Y

PROVIDER: S-EPMC2570880 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Full-length Escherichia coli SecA dimerizes in a closed conformation in solution as determined by cryo-electron microscopy.

Chen Yong Y Pan Xijiang X Tang Ying Y Quan Shu S Tai Phang C PC Sui Sen-Fang SF

The Journal of biological chemistry 20080904 43

SecA is an obligatory component of the Escherichia coli general secretion pathway. However, the oligomeric structure of SecA and SecA conformational changes during translocation processes are still unclear. Here we obtained the three-dimensional structure of E. coli wild-type full-length SecA in solution by single particle cryo-electron microscopy and determined its oligomeric organization. In this structure, SecA occurs as a dimer in which the two protomers are arranged in an antiparallel mode, ...[more]

PMID: 18772144

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