Departments of Biology, Computer Science and Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064, USA.|Departments of Biology, Computer Science and Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064, USA.|Departments of Biology, Computer Science and Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064, USA.|Departments of Biology, Computer Science and Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064, USA.