[1] Tsinghua Univ, Struct Biol Ctr, Sch Life Sci, Beijing 100084, Peoples R China
[2] Tsinghua Univ, Sch Med, Beijing 100084, Peoples R China
[3] Scripps Res Inst, Dept Integrat Struct & Computat Biol, La Jolla, CA 92037 USA
[4] Scripps Res Inst, Dept Chem, La Jolla, CA 92037 USA