1. Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Boulder, Colorado 80309, USA
2. Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
3. The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA;
4. Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, Observatory 7925, South Africa
5. Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA