Bio-Protocol (Oct 2012)

Isolation of Inner Membrane Vesicles from Escherichia coli by Using an Affinity Tag

  • Gang Li,
  • Kevin Young

DOI
https://doi.org/10.21769/bioprotoc.273
Journal volume & issue
Vol. 2, no. 20

Abstract

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This protocol was developed in a project aimed to identify the inner membrane proteins localizing to cell poles in Escherichia coli (E. coli). By using a known polar protein Tar as a tag, we isolated pole-derived inner membrane vesicles by affinity capture. The specificity of the polar vesicle isolation was confirmed by mass spectrometry that identified more than one hundred proteins, most of which are known inner membrane proteins, including other known polar proteins. This protocol, or if adapted properly by choosing other affinity targets, is well suited to isolate other membrane domains of interest for identification of proteins or lipid composition.