Affiliation: | aDepartment of Chemistry.;dQB3 Institute and ;eDepartment of Molecular and Cellular Biology, University of California, Berkeley, CA 94720-3220; ;fDivision of Physical Biosciences, Lawrence Berkeley National Laboratory, Berkeley, CA 94720-3220; ;bDepartment of Biochemistry and Biophysics, University of California, San Francisco, CA 94143-2280; and ;cHoward Hughes Medical Institute, Chevy Chase, MD 20815-6789 |