1. Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States
2. Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
3. Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
4. School of Medicine, University of California, San Diego, La Jolla, California, 92093, United States