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arXiv · 0712.2689

Corrections to the Saffman-Delbruck mobility for membrane bound proteins

Ali Naji·Alex J. Levine·Philip A. Pincus
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Abstract

Recent experiments by Y. Gambin et al. [PNAS 103, 2098 (2006)] have called into question the applicability of the Saffman-Delbruck diffusivity for proteins embedded in the lipid bilayers. We present a simple argument to account for this observation that should be generically valid for a large class of transmembrane and membrane bound proteins. Whenever the protein-lipid interactions locally deform the membrane, that deformation generates new hydrodynamic stresses on the protein-membrane complex leading to a suppression of its mobility. We show that this suppression depends on the protein size in a manner consistent with the work of Y. Gambin et al.

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Ali Naji, Alex J. Levine, Philip A. Pincus. 2007-12-17. Corrections to the Saffman-Delbruck mobility for membrane bound proteins. https://doi.org/10.1529/biophysj.107.119222

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