1. Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
2. Mass Spectrometry Research Center, Vanderbilt University, Nashville, Tennessee 37232, United States
3. ExxonMobil Research and Engineering Company, Annandale, New Jersey 08801, United States
4. Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
5. Bruker Daltonics, Billerica, Massachusetts 01821, United States
6. Department of Pharmacology and Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States