Backbone Hydrogen Bond Energies in Membrane Proteins Are Insensitive to Large Changes in Local Water Concentration.

ABSTRACT: A hallmark feature of biological lipid bilayer structure is a depth-dependent polarity gradient largely resulting from the change in water concentration over the angstrom length scale. This gradient is particularly steep as it crosses the membrane interfacial regions where the water concentration drops at least a million-fold along the direction of the bilayer normal. Although local water content is often assumed to be a major determinant of membrane protein stability, the effect of the water-induced polarity gradient upon backbone hydrogen bond strength has not been systematically investigated. We addressed this question by measuring the free energy change for a number of backbone hydrogen bonds in the transmembrane protein OmpW. These values were obtained at 33 backbone amides from hydro

SUBMITTER: Lessen HJ 

PROVIDER: S-EPMC7610216 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature