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arXiv · cond-mat/0211505

Liquid-liquid phase separation of a surfactant-solubilized membrane protein

R. Piazza·M. Pierno·E. Vignati·G. Venturoli·F. Francia·A. Mallardi·G. Palazzo
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Abstract

The phase behavior of membrane proteins stems from a complex synergy with the amphiphilic molecules required for their solubilization. We show that ionization of a pH-sensitive surfactant, LDAO, bound to a bacterial photosynthetic protein, the Reaction Center (RC), leads in a narrow pH range to protein liquid-liquid phase separation in surprisingly stable `droplets', forerunning reversible aggregation at lower pH. Phase segregation is promoted by increasing temperature and hindered by adding salt. RC light-absorption and photoinduced electron cycle are moreover strongly affected by phase segregation.

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R. Piazza, M. Pierno, E. Vignati, G. Venturoli, F. Francia, A. Mallardi, G. Palazzo. 2002-11-22. Liquid-liquid phase separation of a surfactant-solubilized membrane protein. https://doi.org/10.1103/physrevlett.90.208101

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