Jonathan received his B.S. in Chemistry from Indiana University (IU) in 2017 with a minor in German. While at IU, he was a research assistant in Professor Mu-Hyun Baik‘s lab where he investigated mechanisms underlying organometallic catalysts for CO₂ reduction using chemical simulations and density functional theory (DFT). He then became a research assistant under the supervision of Professor Megan Thielges where he studied the structure of proteins expressed with non-native amino acid vibrational probes using FTIR spectroscopy. Following graduation, he served as a laboratory technician in the Thielges lab from 2017-2018 where he worked on cyano-labeled cyctochrome P450 variant protein expression and purification.

Jonathan joined the Prentice Group in the fall of 2018, where he now works on fundamental charge inversion ion activation strategies using next-generation mass spectrometry instrumentation. This work is focused on using fundamental charge inversion ion/ion chemistries to enable the enhanced structural identification phospholipids in imaging mass spectrometry (IMS). In addition, he is working in collaboration with Dr. Joseph Zackular (University of Pennsylvania, Children’s Hospital of Pennsylvania) to study the metabolic interactions of Clostridium difficile during co-infection with other gut microbiota in the gastrointestinal tract. This application utilizes high resolution accurate mass (HRAM) imaging mass spectrometry to identify biomolecules of interest and elucidate biochemical mechanisms during Clostridium difficile infection.

Jonathan graduated with his PhD in the summer of 2023 and now works as a Postdoctoral Researcher at Eli Lilly in Indianapolis, IN.

Awards

• James and Laura Winefordner Graduate Student Award (University of Florida, 2022)
• Robert G. and Jo Bates Graduate Fellowship Award (University of Florida, 2022)
• ASMS Conference Graduate Student Travel Award (American Society for Mass Spectrometry, 2022)
• College of Liberal Arts & Sciences Graduate Student Travel Award (University of Florida, 2021)
• Charles and Monica Burkett Family Summer Fellowship (University of Florida, 2021)
• Graduate Student Teaching Award (University of Florida, 2020)
• Grinter Research Fellowship (University of Florida, 2018)
• Robert & Marjorie Mann Summer Research Grant (Indiana University, 2016)

Publications

• Smith, A.B., Jenior, M.L., Keenan, O., Hart, J.L., Specker, J.T., Abbas, A., Rangel, P.C., Di, C., Green, J., Bustin, K.A. and Gaddy, J.A. (2022). Enterococci enhance Clostridioides difficile pathogenesis. Nature, 611(7937), 780-786.
• Specker, J.T., Smith, A.B., Keenan, O., Zackular, J.P. and Prentice, B.M. (2022). Investigation of Microbial Cooperation via Imaging Mass Spectrometry Analysis of Bacterial Colonies Grown on Agar and in Tissue During Infection. Journal of Visualized Experiments: Jove, (189), e64200.
• Specker, J. T., Van Orden, S. L., Ridgeway, M. E., & Prentice, B. M. (2020). Identification of phosphatidylcholine isomers in imaging mass spectrometry using gas-phase charge inversion ion/ion reactions. Analytical Chemistry, 92(19), 13192-13201.
• Ramos, S., Le Sueur, A. L., Horness, R. E., Specker, J. T., Collins, J. A., Thibodeau, K. E., & Thielges, M. C. (2019). Heterogeneous and highly dynamic interface in plastocyanin–cytochrome f complex revealed by site-specific 2D-IR spectroscopy. The Journal of Physical Chemistry B, 123(9), 2114-2122.

Teaching Experience

• TA- CHM2051 – General Chemistry II Honors (UF, 2020)
• TA- CHM 4130 – Instrumental Analysis (UF, 2019-2020)
• TA- CHM3120L – Analytical Chemistry Lab (UF, 2018-2020)

Presentations

• Jonathan T. Specker*, Alexander B. Smith, Joseph P. Zackular, Boone M. Prentice, “Investigation of microbial cooperation during Clostridioides difficile infection using imaging mass spectrometry,” Oral presentation, ID–308946, June 8, 2022, Proceedings of the 70th ASMS Conference on Mass Spectrometry and Allied Topics, Minneapolis, MN, June 5-9, 2022.
• Julia R. Bonney*, Woo-Young Kang, Jonathan T. Specker, Boone M. Prentice, “Relative quantification of lipid isomers in imaging mass spectrometry using gas-phase charge inversion ion/ion reactions and infrared multiphoton dissociation,” Oral presentation, ID–310957, June 8, 2022, Proceedings of the 70th ASMS Conference on Mass Spectrometry and Allied Topics, Minneapolis, MN, June 5-9, 2022.
• Troy R. Scoggins*, Jonathan T. Specker, Boone M. Prentice, “Multiple ion isolation and accumulation events for selective chemical noise reduction and dynamic range enhancement in MALDI imaging mass spectrometry,” Poster presentation, ID–310834, June 8, 2022, Proceedings of the 70th ASMS Conference on Mass Spectrometry and Allied Topics, Minneapolis, MN, June 5-9, 2022.
• Jonathan T. Specker*, Boone M. Prentice, “Imaging mass spectrometry of isobaric sphingomyelins via gas-phase charge inversion ion/ion reactions enabled on a hybrid FTICR MS,” Oral presentation, ID–307823, November 4, 2021, Proceedings of the 69^th ASMS Conference on Mass Spectrometry and Allied Topics, Philadelphia, PA, November 1-4, 2021. 
• Julia R. Bonney*, Woo-young Kang, Jonathan T. Specker, Boone M. Prentice, “Implementation of IRMPD on an FTICR mass spectrometer for lipid identification using gas-phase charge inversion ion/ion reactions,” Oral presentation, ID–306925, November 4, 2021, Proceedings of the 69^th ASMS Conference on Mass Spectrometry and Allied Topics, Philadelphia, PA, November 1-4, 2021. 
• Jonathan T. Specker*, Alexander B. Smith, Joseph P. Zackular, Boone M. Prentice, “Investigation of microbial cooperation during Clostridioides difficile infection using imaging mass spectrometry,” Oral presentation, September 11, 2021, American Chemical Society FAME Mini-Session, University of Florida, Gainesville, FL, September 11, 2021.
• Jonathan T. Specker*, Boone M. Prentice, “Gas-phase separation and concentration of phosphatidylcholine lipids using charge inversion ion/ion reactions enabled on a FTICR mass spectrometer,” Oral presentation, ID–301075, June 1, 2020, Proceedings of the 68^th ASMS Conference on Mass Spectrometry and Allied Topics, Online Meeting, June 1-12, 2020.
• Jonathan T. Specker*, Steven L. Van Orden, Boone M. Prentice, “Identification of phosphatidylcholine lipids in imaging mass spectrometry using gas-phase charge inversion ion/ion reactions enabled on a FTICR mass spectrometer,” Oral presentation, ID–299803, June 3, 2019, Proceedings of the 67^th ASMS Conference on Mass Spectrometry and Allied Topics, Atlanta, GA, June 2-6, 2019.