1. Department of Microbiology, Immunology, and Molecular Genetics, University of California at Los Angeles (UCLA), Los Angeles, CA 90095-7364, USA.
2. California NanoSystems Institute, UCLA, 237 BSRB, 615 Charles E. Young Drive South, Los Angeles, CA 90095-7364, USA.
3. Structural Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, TX 77030, USA.
4. Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA.
5. Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
6. Department of Psychology, UCLA, Los Angeles, CA 90095-7364, USA.