1. Department of Infectious Disease Epidemiology, St. Mary's Hospital Campus, Imperial College London, London W2 1PG, United Kingdom
2. Molecular Genetics Laboratory, Instituto de Tecnologia Quimica e Biologica da Universidade Nova de Lisboa (ITQB/UNL), Oeiras, Portugal
3. Wellcome Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
4. Department of Medicinal Chemistry, School of Pharmacy, and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23298-0049