Origin of subdiffusion of water molecules on cell membrane surfaces

Eiji Yamamoto; Takuma Akimoto; Masato Yasui; Kenji Yasuoka

doi:10.1038/srep04720

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arXiv · 1401.7776

Origin of subdiffusion of water molecules on cell membrane surfaces

Eiji Yamamoto·Takuma Akimoto·Masato Yasui·Kenji Yasuoka

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Abstract

Water molecules play an important role in providing unique environments for biological reactions on cell membranes. It is widely believed that water molecules form bridges that connect lipid molecules and stabilize cell membranes. Using all-atom molecular dynamics simulations, we show that translational and rotational diffusion of water molecules on lipid membrane surfaces exhibit subdiffusion. Moreover, we provide evidence that both divergent mean trapping time (continuous-time random walk) and long-correlated noise (fractional Brownian motion) contribute to this subdiffusion. These results suggest that subdiffusion on cell membranes causes the water retardation, an enhancement of cell membrane stability, and a higher reaction efficiency.

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Eiji Yamamoto, Takuma Akimoto, Masato Yasui, Kenji Yasuoka. 2014-01-30. Origin of subdiffusion of water molecules on cell membrane surfaces. https://doi.org/10.1038/srep04720

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