Bio

Christopher Callam received his undergraduate Chemistry degree (BS) from John Carroll University in 1998. He obtained his Ph.D. in Organic Chemistry from The Ohio State University working under the supervision of Dr. Todd Lowary in 2003. From 2003-2004, he was a Ruth L. Kirschstein NIH Post-Doctoral Research Fellow at the University of Pittsburgh working with Dr. Dennis Curran, In 2004, he returned to the Department of Chemistry at The Ohio State University.

Research Overview

The general area of our research is focused on synthetic organic chemistry. We are developing synthetic pathways for small molecule chemical reactivators for protection from organophosphorus agents, including chemical nerve agents and pesticides. Our research focuses on combating the effects of organophosphorus (OP) compounds. Organophosphorus (OP) compounds are inhibitors of acetylcholinesterase (AChE), an enzyme responsible for the rapid hydrolysis of acetylcholine (ACh). ACh is a neurotransmitter found in the central and peripheral nervous systems of humans and many other species; it plays key roles both in the transmission of action potentials and in muscle movement. AChE typically hydrolyzes acetylcholine to choline and acetate. OP compounds inhibit ACh activity by covalently binding to the active site residue. The phosphylated enzyme becomes increasingly resistant to reactivation, and a process called “aging” subsequently occurs. After aging occurs, current treatments are no longer effective options and new medical countermeasures must be developed to treat the aged form (resurrection).

We work with Dr. Christopher Hadad and Dr. Craig McElroy to develop novel drug-like molecules that are capable of reactivating and resurrecting OP-exposed AChE adducts. Collectively our investigator team conceives of novel structures for accomplishing the covalent chemistry involved in these processes.

Teaching

As the director of undergraduate organic laboratories, I have been heavily involved in various service activities for the Department, including management and mentoring of graduate and undergraduate teaching assistants, curriculum development, scheduling and enrollment for the organic course, and development of new lab experiments. I am interested in improving student understanding and incorporating technology into the organic chemistry lecture and laboratory.

Publications

1. Enoch, A.; Kulyk, D.; Callam, C.S.; Hadad, C.M.; Badu-Tawiah, A.* Mass Spectrometry Approach for Differentiation of Positional Isomers of Saccharides: Toward Direct Analysis of Rare Sugars. Anal. Chem. 2023, 95 (13), 5645-5642.

DOI: 10.1021/acs.analchem.2c05375

2. Paul, N.M.*; Yoder, R.J.*; Callam, C.S.* The Use of ChemDraw throughout the Organic Laboratory Curriculum. J. Chem. Ed. 2019, 96 (11), 2638-2642.

DOI: 10.1021/acs.jchemed.9b00010

3. Franjesevic, A.J.; Sillart, S.B.; Beck, J.M.; Vyas, S.; Callam, C.S.; Hadad, C.M.* Resurrection and Reactivation of Acetylcholinesterase and Butyrylcholinesterase. Chemistry - A European Journal. 2019, 25 (21), 5337-5371.

DOI: 10.1002/chem.201805075

4. Zhuang Q.; Young A.; McKenney R.; Callam C.S.; McElroy C.A.; Dogan-Ekici O.D.; Yoder R.J.; Hadad C.M.* Efforts Towards Treatments Against Aging of Organophosphorus-inhibited Acetylcholinesterase. Annals of the New York Academy of Sciences, 2016 1(1374), 94-104.

DOI: 10.1111/nyas.13124

5. Zhuang, Q.; Franjesevic, A.J.; Corrigan, T.S.; Coldren, W.H.; Dicken, R.; Sillart, S.; DeYong, A.; Yoshino, N.; Smith, J.; Fabry, S.; Fitzpatrick, K.; Blanton, T.; Joseph, J.; Yoder, R.J.; McElroy, C.A.; Ekici, O.D.; Callam, C.S., Hadad, C.M.* Demonstration of in vitro Resurrection of Aged Acetylcholinesterase After Exposure to Organophosphorus Chemical Nerve Agents. J. Med. Chem. 2018, 61 (16), 7034-7042.

DOI: 10.1021/acs.jmedchem.7b01620

6. Yoder, R.J.; Zhuang, Q.; Beck, J.M.; Franjesevic, A.; Blanton, T.G.; Sillart, S.; Secor, T.; Guerra, L.; Brown, J.D.; Reid, C.; McElroy, C.A.; Ekici, O.D.; Callam, C.S.; Hadad, C.M.* Study of para-Quinone Methide Precursors toward the Realkylation of Aged Acetylcholinesterase. ACS Med. Chem. Lett. 2017, 8 (6), 622-627.

DOI: 10.1021/acsmedchemlett.7b00037

7. Verne, G. N.; Price, D. D.; Callam, C. S.; Zhang, B.; Peck, J.; Zhou, Q. Q.*; Viscerosomatic Facilitation in a Subset of IBS Patients, an Effect Mediated by N-methyl-D-aspartate Receptors. The Journal of Pain: Official Journal of the American Pain Society. 2012, 13, 901-909.

DOI: 10.1016/j.jpain.2012.06.002

8. Zhou, Q. Q.; Price D. D.; Dreher K. L.; Pronold, B.G.; Callam C. S.; Sharma, J.G: Verne, G. N.* Localized Colonic Stem Cell Transplantation Enhances Tissue Regeneration in Murine Colitis. Journal Cellular and Molecular Medicine. 2012, 16, 1900-1915.

DOI: 10.111/j.1582-4934.2011.01485.x

9. Zhou, Q. Q.; Price, D. D.; Callam, C. S.; Woodruff, M. A., Verne, G. N.* Effects of the N-methyl-D-aspartate Receptor on Temporal Summation of Second Pain (wind-up) in Irritable Bowel Syndrome. Journal of Pain: Official Journal of the American Pain Society. 2011, 12 (2), 297-303.

DOI: 10.1016/j.pain.2010.09.002

10. Darwish,O.S.;Callam,C.S.;Hadad,C.M.;Lowary,T.L.*RegioselectivityinAlkylationReactionsof1,2-O- Stannylene Acetals of D-Arabinofuranose. J. Carb. Chem. 2003, 22, 963-981.

DOI: 10.1081/CAR-120026604

11. Wagner,T.R.;Gadikota,R.R.;Callam,C.S.;Lowary,T.L.*1-(2’,3’-5’-O-benzoyl-β-D-lyxofuranosyl)-5-fluoro- uracil. Acta. Cryst. 2003, E59, o1063-o1065.

DOI: 10.1107/S1600536803012352

12. Callam,C.S.;Gadikota,R.R.;Lowary,T.L.*AnEfficientRoutetoPyrimidineNucleosideswiththe2,3-anhydro-β- D-Lyxofuranosyl Stereochemistry. Synlett. 2003, 9, 1271-1274.

DOI: 10.1055/s-2003-40335

13. Gadikota,R.R.;Callam,C.S.;Appelmelk,B.J.;Lowary,T.L.*SynthesisofOligosaccharideFragmentsof Mannosylated Lipoarabinomannan Appropriately Functionalized for Neoglyconjugate Preparation. J. Carb. Chem. 2003, 22, 459-480.

DOI: 10.1081/CAR-120021696

14. Gadikota,R.R.;Keller,A.I.;Callam,C.S.;Lowary,T.L.*EfficientSynthesesoftrans-(+)-Laurediolfrom Carbohydrate Precursors. Tetrahedron Assym. 2003, 14, 737-742.

DOI: 10.1016/S0957-4166(03)00078-8

15. Callam,C.S.;Gadikota,R.R.;Krein,D.M.;Lowary,T.L.*2,3-AnhydrosugarsinGlycosideBondSynthesis.Low Temperature NMR and Computational Mechanistic Investigations. J. Am. Chem. Soc. 2003, 125, 13112-13119.

DOI: 10.1021/ja0349610

16. Gadikota,R.R.;Callam,C.S.;Wagner,T.,DelFriano,B.;Lowary,T.L.*2,3-AnhydrosugarsinGlycosideBond Synthesis. Highly Stereoselective Syntheses of Oligosaccharides Containing α- and β-Arabinofuranosyl Linkages. J. Am. Chem. Soc. 2003, 125, 4155-4165.

DOI: 10.1021/ja029302m

17. Gadikota,R.R.;Callam,C.S.;Lowary,T.L.*TotalSynthesisof(6S,7S,9S,10S)-6,9-epoxynonadec-18-ene-7,10-diol and Formal Synthesis of (+)-trans-Kumausyne from D-Arabinose. J. Org. Chem. 2001, 66, 9046-9051.

DOI: 10.1021/jo010830a

18. Callam,C.S.;Lowary,T.L.*SynthesisandConformationalInvestigationofMethyl4a-carba-D-arabinofuranosides. J. Org. Chem. 2001, 66, 8961-8972.

DOI: 10.1021/jo010827r

19. Callam,C.S.;Singer,S.J.;Lowary,T.L.;Hadad,C.M.*ComputationalAnalysisofthePotentialEnergySurfacesof Glycerol in the Gas and Aqueous Phases. Effects of Level of Theory, Basis Set, and Solvation on Strongly Intramolecularly Hydrogen-Bonded Systems. J. Am. Chem. Soc. 2001, 123, 11743-11754.

DOI: 10.1021/ja011785r

20. Callam, C.S.; Gadikota, R.R.; Lowary, T.L.* Sensitivity of 1JC1-H1 Magnitudes to Anomeric Stereochemistry in 2,3- Anhydro-O-furanosides. J. Org. Chem. 2001, 66, 4549-4558.

DOI: 10.1021/jo001747a

21. Callam,C.S.;Lowary,T.L.*SuzukiCrossCouplingReactions:SynthesisofUnsymmetricalBiarylsintheOrganic Laboratory. J. Chem. Educ. 2001, 78, 964-966.

DOI: 10.1021/ed078p947

22. Gadikota,R.R.;Callam,C.S.;Lowary,T.L.*StereocontrolledSynthesisof2,3-Anhydro-β-D-lyxofuranosyl Glycosides. Org. Lett. 2001, 3, 607-610.

DOI: 10.1021/ol007008y

23. Callam,C.S.;Lowary,T.L.*SynthesisofMethyl2,3,5-tri-O-benzoyl-α-D-arabinofuranosideintheOrganic Laboratory. J. Chem. Educ. 2001, 78, 73-74.

DOI: 10.1021/ed078p73

24. Callam,C.S.;Gadikota,R.R.;Lowary,T.L.*AnEfficientSynthesisofMethyl2,3-anhydro-α-D-ribofuranoside. Carbohydr. Res. 2001, 330, 267-270.

DOI: 10.1016/S0008-6215(00)00277-9

25. Callam, C. S.; Lowary, T. L.* Total Synthesis of Methyl 4a-carba-D-arabinofuranosides. Org. Lett. 2000, 2, 167- 169.

DOI: 10.1021/ol9912682