1. Departments of Biology, Pathology, Chemistry, and Psychiatry, University of Utah, Salt Lake City, Utah 84112, Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines, Department of Physical Sciences, College of Science, University of the Philippines Baguio, Baguio City, Philippines, The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, and Cognetix, Inc., 421 Wakara Way, Salt Lake City, Utah 84108