Does CO2 permeate through aquaporin-1?
Aquaporins facilitate water permeation across biological membranes. Additionally, glycerol and other small neutral solutes are permeated by related aquaglyceroporins. The role of aquaporins in gas permeation has been a long-standing and controversially discussed issue. We present an extensive set of atomistic molecular dynamics simulations that address the question of CO(2) permeation through human aquaporin-1. Free energy profiles derived from the simulations display a barrier of approximately 23 kJ/mol in the aromatic/arginine constriction region of the water pore, whereas a barrier of approximately 4 kJ/mol was observed for a palmitoyloleoylphosphatidylethanolamine lipid bilayer membrane. The results indicate that significant aquaporin-1-mediated CO(2) permeation is to be expected only in membranes with a low intrinsic CO(2) permeability.
Hub
Jochen S
JS
Computational Biomolecular Dynamics Group, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany.
de Groot
Bert L
BL
D051398:Aquaporin 1 / Q000737:chemistry*; D020346:Aquaporins / Q000737:chemistry; D001703:Biophysics / Q000379:methods*; D002244:Carbon / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry*; D003198:Computer Simulation; D005990:Glycerol / Q000737:chemistry; D006801:Humans; D008051:Lipid Bilayers; D010100:Oxygen / Q000737:chemistry; D010539:Permeability; D012984:Software; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D020346:Aquaporins; D008051:Lipid Bilayers; D014867:Water; D002245:Carbon Dioxide; D051398:Aquaporin 1; D002244:Carbon; D005990:Glycerol; D010100:Oxygen