Purification and functional reconstitution of the bacterial protein translocation pore, the SecYEG complex

Methods Mol Biol. 2010:619:131-43. doi: 10.1007/978-1-60327-412-8_8.


In bacteria, proteins are secreted across the cytoplasmic membrane by a protein complex termed translocase. The ability to study the activity of the translocase in vitro using purified proteins has been instrumental for our understanding of the mechanisms underlying this process. Here, we describe the protocols for the purification and reconstitution of the SecYEG complex in an active state into liposomes. In addition, fluorescence based in vitro assays are described that allow monitoring translocation activity discontinuously and in real time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins / metabolism
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / metabolism*
  • Inclusion Bodies / metabolism
  • Liposomes / metabolism
  • Protein Precursors / metabolism
  • SEC Translocation Channels


  • Bacterial Outer Membrane Proteins
  • Escherichia coli Proteins
  • Liposomes
  • Protein Precursors
  • SEC Translocation Channels
  • outer membrane protein A precursor (E coli)