Preferential insertion of lactose permease in phospholipid domains: AFM observations

Biochim Biophys Acta. 2010 May;1798(5):1014-9. doi: 10.1016/j.bbamem.2010.01.008. Epub 2010 Jan 21.

Abstract

We report the insertion of a transmembrane protein, lactose permease (LacY) from Escherichia coli (E. coli), in supported lipid bilayers (SLBs) of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG), in biomimetic molar proportions. We provide evidence of the preferential insertion of LacY in the fluid domains. Analysis of the self-assembled protein arrangements showed that LacY: (i) is inserted as a monomer within fluid domains of SLBs of POPE:POPG (3:1, mol/mol), (ii) has a diameter of approx. 7.8nm; and (iii) keeps an area of phospholipids surrounding the protein that is compatible with shells of phospholipids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli / enzymology
  • Lipid Bilayers / chemistry*
  • Membrane Transport Proteins / chemistry*
  • Microscopy, Atomic Force
  • Phosphatidylethanolamines / chemistry
  • Phosphatidylglycerols / chemistry
  • Phospholipids / chemistry*

Substances

  • Lipid Bilayers
  • Membrane Transport Proteins
  • Phosphatidylethanolamines
  • Phosphatidylglycerols
  • Phospholipids
  • 1-palmitoyl-2-oleoylphosphatidylethanolamine
  • 1-palmitoyl-2-oleoylglycero-3-phosphoglycerol
  • lactose permease