Molecular Biology Institute, Center for Genomics and Proteomics, Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1570, USA.|Molecular Biology Institute, Center for Genomics and Proteomics, Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1570, USA.|Molecular Biology Institute, Center for Genomics and Proteomics, Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1570, USA.|Molecular Biology Institute, Center for Genomics and Proteomics, Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1570, USA.