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Updated: Jun 16, 2026

Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
Preferential insertion of lactose permease in phospholipid domains: AFM observations
Laura Picas1, Adrián Carretero-Genevrier, M Teresa Montero
1Departament de Fisicoquímica, Facultat de Farmàcia, Universitat de Barcelona (UB), Spain.
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.
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