Preparation of liposome containing bacteriorhodopsin with "natural" preferred orientation and detection of its transient photoresponse

作者：Huang L; Ming M; Liu J; Liu J; Li QG; Ding JD

来源：Acta Biochimica et Biophysica Sinica, 2003, 35(4): 391-395.

• bacteriorhodopsin
• membrane protein
• self assembly
• liposome

Bacteriorhodopsin is a membrane protein of halobacteria and functions as a light-driven protein pump. After we isolated bR from cultured halobacteria, bR was mixed with amphiphilic DPPC under different pH. The liposomes were formed after sonication. The remaining biological activity of bR as a proton pump viras then verified and pulsed-light-induced proton movement was detected, while liposomes mere observed via TEM and light scattering. Although there was no noticeable difference in morphologies of both vesicles formed at pH = 2.5 and pH = 7.0, the orientations of bR in both liposomes were found to be opposite under these two conditions. This experiment confirmed that the protein bR, when self-assembling into liposomes under acid medium, kept the similar orientation as in the natural plasmid membrane. Such a "normal" orientation was, however, different from most of reports in the literature about liposomes prepared under normal neutral conditions.

• 出版日期2003-4
• 单位复旦大学