Department of Biochemistry and Howard Hughes Medical Institute The University of Texas Southwestern Medical Center Dallas, Texas 75235 Department of Chemistry and Biochemistry University of Oklahoma, Norman, Oklahoma 73019 Departments of Biochemistry and Pharmacology The University of Texas Southwestern Medical Center Dallas, Texas 75235 Department of Biochemistry and Molecular Biology University of Oklahoma, Stillwater, Oklahoma 74078(1999-05-01時点)