A refined structure of human aquaporin-1

A refined structure of the human water channel aquaporin-1 is presented. Th e model rests on the high resolution X-ray structure of the homologous bact erial glycerol transporter GlpF, electron crystallographic data at 3.8 Angs trom resolution and a multiple sequence alignment of the aquaporin superfam ily. The crystallographic R and free R values (36.7% and 37.8%) for the ref ined structure are significantly lower than for previous models. Improved g eometry and enhanced stability in molecular dynamics simulations demonstrat e a significant improvement of the aquaporin-1 structure. Comparison with p revious aquaporin-1 models shows significant differences, not only in the l oop regions, but also in the core of the water channel. (C) 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.