Creation of cross-linked bilayer membranes that can incorporate membrane proteins from oligo-Asp-based peptide gemini surfactants.
We designed novel bilayer-forming amphiphiles based on the cyclic oligo-Asp-based peptide gemini (PG) surfactants cr-D2C12 and cr-D3C12, which consist of -Cys(Asp)nCys- (n = 2 or 3) as a core peptide and two Cys residues containing a dodecylamidomethyl group. Dynamic light scattering and transmission electron microscopy measurements revealed the formation of spherical bilayer membranes that could incorporate the light-harvesting antenna complex 2 (LH2) from Rhodopseudomonas acidophila . Furthermore, this proteoliposome-like conjugate could be assembled onto cationized glass and mica to form planar bilayer membranes incorporating LH2. Using atomic force microscopy, we observed LH2 protruding (ca. 1.2-1.5 nm) from flat terraces of the planar bilayer membranes formed from cr-D2C12 or cr-D3C12. Thus, our designed PG surfactants are a new class of bilayer-forming amphiphiles that may be applied to the study of various membrane proteins.
Graduate School of Engineering, Nagoya Institute of Technology , Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555, Japan.
Shuhei
S
Koeda
Katsunari
K
Umezaki
Ayumi
A
Sumino
Tomoyasu
T
Noji
Atsushi
A
Ikeda
Yasushi
Y
Yamamoto
Takehisa
T
Dewa
Keijiro
K
Taga
Mamoru
M
Nango
Toshiki
T
Tanaka
Toshihisa
T
Mizuno
D001224:Aspartic Acid / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000138:chemical synthesis* / Q000737:chemistry; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D012241:Rhodopseudomonas / Q000201:enzymology; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry*
D003432:Cross-Linking Reagents; D045342:Light-Harvesting Protein Complexes; D008051:Lipid Bilayers; D010455:Peptides; D013501:Surface-Active Agents; D001224:Aspartic Acid