1. Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
2. Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Code 6900, 4555 Overlook Avenue SW, Washington, DC 20375, United States
3. Optical Sciences Division, Naval Research Laboratory, Code 5600, 4555 Overlook Avenue SW, Washington, DC 20375, United States
4. Key W Corporation, Hanover, Maryland 21076, United States
5. Lions of Illinois Eye Research Institute, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois 60612, United States