1. Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, CA 94720, USA.
2. Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
3. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
4. Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
5. Department of Laboratory Medicine and Radiation Oncology, University of California, San Francisco, CA 94143, USA.