Protein-Containing Lipid Bilayers Intercalated with Size-Matched Mesoporous Silica Thin Films
详细信息 查看全文
- 作者：Simon Isaksson ; Erik B. Watkins ; Kathryn L. Browning ; Tania Kjellerup Lind ; Marité Cárdenas ; Kristina Hedfalk ; Fredrik Höök ; Martin Andersson
- 刊名：Nano Letters
- 出版年：2017
- 出版时间：January 11, 2017
- 年：2017
- 卷：17
- 期：1
- 页码：476-485
- 全文大小：570K
- ISSN：1530-6992
文摘
Proteins are key components in a multitude of biological processes, of which the functions carried out by transmembrane (membrane-spanning) proteins are especially demanding for investigations. This is because this class of protein needs to be incorporated into a lipid bilayer representing its native environment, and in addition, many experimental conditions also require a solid support for stabilization and analytical purposes. The solid support substrate may, however, limit the protein functionality due to protein–material interactions and a lack of physical space. We have in this work tailored the pore size and pore ordering of a mesoporous silica thin film to match the native cell-membrane arrangement of the transmembrane protein human aquaporin 4 (hAQP4). Using neutron reflectivity (NR), we provide evidence of how substrate pores host the bulky water-soluble domain of hAQP4, which is shown to extend 7.2 nm into the pores of the substrate. Complementary surface analytical tools, including quartz crystal microbalance with dissipation monitoring (QCM-D) and fluorescence microscopy, revealed successful protein-containing supported lipid bilayer (pSLB) formation on mesoporous silica substrates, whereas pSLB formation was hampered on nonporous silica. Additionally, electron microscopy (TEM and SEM), light scattering (DLS and stopped-flow), and small-angle X-ray scattering (SAXS) were employed to provide a comprehensive characterization of this novel hybrid organic–inorganic interface, the tailoring of which is likely to be generally applicable to improve the function and stability of a broad range of membrane proteins containing water-soluble domains.