Photoinduced phase transition of lipid / water / photo-functional surfactant system to obtain membrane protein crystals.

2016 Fiscal Year Final Research Report

• Project/Area Number: 26410003
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical chemistry
• Research Institution: Gunma University
• Principal Investigator: OKUTSU TETSUO 群馬大学, 大学院理工学府, 教授 (20261860)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 結晶成長 / タンパク質 / 光誘起結晶化 / 膜タンパク質 / 光誘起相転移

Outline of Final Research Achievements

We studied photochemically induced phase transition of lipid to obtain membrane protein crystal. Crystallization of membrane proteins is mainly performed by using lipid phase transition as a driving force. In this study, we investigated phase transition of lipid with the use of a photochemical surfactant whose structure is changed by trans-cis isomerization. AZTMA having an azobenzene group was prepared as a photofunctional surfactant. As a result, it was confirmed that the phase transition of lipid phase from cubic phase to lamellar phase induced by trans-cis isomerization reaction of AZTMA by polarization microscopy and X-ray diffraction experiment. Crystallization experiments were carried out using bacteriorhodopsin as a membrane protein. The presence of the membrane protein molecule acted as a driving force causing a phase transition, and crystallization did not observed at the photo phase transition.

Free Research Field

物理化学