Subangstrom Resolution X-Ray Structure Details Aquaporin-Water Interactions

Abstract

Choosing Water Aquaporins are proteins that facilitate transport of water across biological membranes. They must be selective for water, without binding it so tightly as to impede transport, and they must prevent proton transfer by rapid exchange between hydrogen-bonded water molecules. Kosinska Eriksson et al. (p. 1346 ; see the Perspective by Abramson and Vartanian ) describe the subangstrom resolution structure of yeast aquaporin, which allows assignment of side-chain conformations and shows that the H-bond geometry of water molecules prevents proton conductance without compromising water transport.