1. Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX 77030, USA.
2. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX 77030, USA.
3. Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
4. Promega Corporation, Madison, WI 53711, USA.
5. Molecular Biophysics and Integrated Bioimaging, Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.