1 Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA; Department of Chemistry, University of California, Berkeley 94720, USA; Molecular Biophysics and Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley 94720, USA. Electronic address: jcate@lbl.gov.
2 Centre for Environmental Sustainability and Remediation, School of Science, RMIT University, Bundoora, VIC 3083, Australia. Electronic address: andy.ball@rmit.edu.au.