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PubMed · 16352850

SecA dimer cross-linked at its subunit interface is functional for protein translocation.

Lucia B Jilaveanu·Donald Oliver
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Abstract

SecA facilitates protein transport across the eubacterial plasma membrane by its association with cargo proteins and the SecYEG translocon, followed by ATP-driven conformational changes that promote protein translocation in a stepwise manner. Whether SecA functions as a monomer or a dimer during this process has been the subject of considerable controversy. Here we utilize cysteine-directed mutagenesis along with the crystal structure of the SecA dimer to create a cross-linked dimer at its subunit interface, which was normally active for in vitro protein translocation.

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Adenosine TriphosphatasesBacillus subtilisBacterial ProteinsCysteineDimerizationMembrane Transport ProteinsModels, MolecularMutagenesis, Site-DirectedProtein TransportSEC Translocation ChannelsSecA ProteinsJournal ArticleResearch Support, N.I.H., Extramural

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Lucia B Jilaveanu, Donald Oliver. 2006. SecA dimer cross-linked at its subunit interface is functional for protein translocation.. https://doi.org/10.1128/jb.188.1.335-338.2006

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