Redefining the concept of hydration water near soft interfaces

Water determines the properties of biological systems. Therefore, understanding the nature of the mutual interaction between water and biosystems is of primary importance for a proper assessment of any biological activity, e.g., the efficacy of new drugs or vaccines. A conve- nient way to characteri...

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Detalles Bibliográficos
Autores: Martelli, Fausto, Calero Borrallo, Carles, Franzese, Giancarlo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/177392
Acceso en línea:https://hdl.handle.net/2445/177392
Access Level:acceso abierto
Palabra clave:Membranes (Biologia)
Aigua
Hidratació
Sistemes biològics
Membranes (Biology)
Water
Hydration
Biological systems
Descripción
Sumario:Water determines the properties of biological systems. Therefore, understanding the nature of the mutual interaction between water and biosystems is of primary importance for a proper assessment of any biological activity, e.g., the efficacy of new drugs or vaccines. A conve- nient way to characterize the interactions between biosystems and water is to analyze their impact on water density and dynamics in the proximity of the interfaces. It is commonly accepted that water bulk density and dynamical properties are recovered at distances of the order of 1 nm away from the surface of biological systems. This notion leads to the definition of hydration or biological water as the nano- scopic layer of water covering the surface of biosystems and to the expectation that all the effects of the water-interface interaction are limited to this thin region. Here, we review some of our latest contributions, showing that phospholipid membranes affect the water dynam- ics, structural properties, and hydrogen bond network at a distance that is more than twice as large as the commonly evoked 1 nm thick layer and of the order of 2.4 nm. Furthermore, we unveil that at a shorter distance 0:5 nm from the membrane, instead, there is an addi- tional interface between lipid-bound and unbound water. Bound water has a structural role in the stability of the membrane. Our results imply that the concept of hydration water should be revised or extended and pave the way to a deeper understanding of the mutual interac- tions between water and biological systems.