Interfacial water molecules at biological membranes: Structural features and role for lateral proton diffusion.

Proton transport at water/membrane interfaces plays a fundamental role for a myriad of bioenergetic processes. Here we have performed ab initio molecular dynamics simulations of proton transfer along two phosphatidylcholine bilayers. As found in previous theoretical studies, the excess proton is pre...

Full description

Bibliographic Details
Main Authors: Trung Hai Nguyen, Chao Zhang, Ewald Weichselbaum, Denis G Knyazev, Peter Pohl, Paolo Carloni
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2018-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5825111?pdf=render
Description
Summary:Proton transport at water/membrane interfaces plays a fundamental role for a myriad of bioenergetic processes. Here we have performed ab initio molecular dynamics simulations of proton transfer along two phosphatidylcholine bilayers. As found in previous theoretical studies, the excess proton is preferably located at the water/membrane interface. Further, our simulations indicate that it interacts not only with phosphate head groups, but also with water molecules at the interfaces. Interfacial water molecules turn out to be oriented relative to the lipid bilayers, consistently with experimental evidence. Hence, the specific water-proton interaction may help explain the proton mobility experimentally observed at the membrane interface.
ISSN:1932-6203