1. Institut de Pharmacologie et Biologie Structurale CNRS UMR5089, Toulouse F-31077, France, International University Bremen, Campus Ring 1, D-28759 Bremen, Germany, Laboratório de Engenharia de Processos, Ambiente e Energia, Faculdade de Engenharia da Universidade do Porto, Porto, Portugal, The Division of Structural Biology, University of Oxford, Roosevelt Drive, OX3 7BN, United Kingdom, and Laboratoire Interactions Moleculaires et Reactivité Chimique et Photochimique UPS/CNRS UMR5623, Toulouse, France