Rouvinski, Alexander, Dejnirattisai, Wanwisa, Guardado-Calvo, Pablo, Vaney, Marie-Christine, Sharma, Arvind, Duquerroy, Stéphane, Supasa, Piyada, Wongwiwat, Wiyada, Haouz, Ahmed, Barba-Spaeth, Giovanna, Mongkolsapaya, Juthathip, Rey, Félix A., Screaton, Gavin R., Virologie Structurale - Structural Virology, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Division of Immunology and Inflammation, Department of Medicine, Imperial College London-Hammersmith Hospital Campus, Protéopole, Siriraj Hospital, Mahidol University, Mahidol University [Bangkok], We acknowledge support from the European Commission FP7 Programme for the DENFREE project under Grant Agreement number 282 378FP7 (F.A.R., J.M. and G.R.S.), the ‘Integrative Biology of Emerging Infectious Diseases’ Labex (Laboratoire d’Excellence) grant number ANR-10-LABX-62-IBEID (French Government’s ‘Investissements d’Avenir’ program ) (F.A.R.) the National Institute for Health Research Biomedical Research Centre, Funding Scheme, UK (G.R.S.), and the NEUTRAVIR grant from Région Ile-de-France (DIM-Maladies Infectieuses) (F.A.R.). G.R.S. is a Wellcome Trust Senior Investigator., We thank Watchara Kasinrerk and Chunya Putthikhunt for anti-dengue anti-DomIII mAb 2C8, J. Freire and G. Bowler for help and discussion, the staff at the crystallogenesis and chemogenomic & biological screening facilities at Institut Pasteur, the staff at beamlines PX1 and PX2 at SOLEIL synchrotron (Saclay, France), the staff at beamlines ID23-1, ID23-2, ID29 and IB30B at the European Synchrotron Radiation Facility (Grenoble, France), Fabrice Agou at Institut Pasteur for the MALS system., ANR-10-LABX-0062,IBEID,Integrative Biology of Emerging Infectious Diseases(2010), European Project: 282378,EC:FP7:HEALTH,FP7-HEALTH-2011-single-stage,DENFREE(2012), Centre National de la Recherche Scientifique (CNRS)-Institut Pasteur [Paris], and Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS)