1. Centre de Biologie Structurale, CNRS UMR 5048—INSERM UMR 1054, University of Montpellier, 34090 Montpellier, France
2. Institut Montpelliérain, Alexander Grothendieck, CNRS, University of Montpellier, 34095 Montpellier, France
3. Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, Unted States