1. Department of Biochemistry and Molecular Biology; Oregon Health & Science University; 3181 SW Sam Jackson Park Road Portland OR 97239-3098 USA
2. Physiology and Pharmacology; Oregon Health & Science University; 3181 SW Sam Jackson Park Road Portland OR 97239-3098 USA
3. Department of Biochemistry and Virginia Tech Center for Drug Discovery; M/C 0308 Virginia Tech Blacksburg VA 24061 USA