1. California NanoSystems Institute (CNSI), University of California , Los Angeles, California , United States
2. Department of Chemistry & Biochemistry, University of California , Los Angeles, Los Angeles, California , United States
3. Department of Microbiology, Immunology and Molecular Genetics, University of California , Los Angeles, CA , United States
4. National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California , United States