Erik Farquhar

Brookhaven National Laboratory

NSLS-II
Bldg. 745, Room 106
P.O. Box 5000
Upton, NY 11973-5000

(631) 344-8174
efarquhar@bnl.gov

Research | Education | Publications

Research Activities

Methodological developments in synchrotron X-ray footprinting (instrumentation and experimental strategies) to enable its application to increasingly complex systems, X-ray absorption and emission spectroscopies for the structure of metal sites in biology, integration of multiple synchrotron-based methods to understand biological systems up to the cellular scale.

Education

After completing undergraduate studies at the University at Buffalo (SUNY) with a bachelors in science degree in 2002, Erik later undertook doctoral training in the Department of Chemistry at the University of Minnesota, leading to a Ph.D. degree in inorganic chemistry in 2010.

Selected Publications

• Ahmed E, Jain R, Schlatzer D, et al (2025) Quantitative readout of methionine residue solvent accessibility in E. coli cells using radiolytic hydroxyl radical labeling and mass spectrometry. Biochemical and Biophysical Research Communications 762:151745. https://doi.org/10.1016/j.bbrc.2025.151745
• Jain R, Farquhar ER, Dhillon NS, et al (2024) Multiplex Trifluoromethyl and Hydroxyl Radical Chemistry Enables High-Resolution Protein Footprinting. Analytical Chemistry. https://doi.org/10.1021/acs.analchem.4c04610
• Farquhar ER, Vijayalakshmi K, Jain R, et al (2023) Intact mass spectrometry screening to optimize hydroxyl radical dose for protein footprinting. Biochemical and Biophysical Research Communications 671:343–349. https://doi.org/10.1016/j.bbrc.2023.06.020
• Jain R, Dhillon NS, Farquhar ER, et al (2022) Multiplex Chemical Labeling of Amino Acids for Protein Footprinting Structure Assessment. Analytical Chemistry 94:9819–9825. https://doi.org/10.1021/acs.analchem.2c01640
• Jain R, Abel D, Rakitin M, et al (2021) New high-throughput endstation to accelerate the experimental optimization pipeline for synchrotron X-ray footprinting. Journal of Synchrotron Radiation 28:1321–1332. https://doi.org/10.1107/s1600577521005026
• Asuru A, Farquhar ER, Sullivan M, et al (2019) The XFP (17-BM) beamline for X-ray footprinting at NSLS-II. Journal of Synchrotron Radiation 26:1388–1399. https://doi.org/10.1107/s1600577519003576
• Schwalenstocker K, Paudel J, Kohn AW, et al (2016) Cobalt Kβ valence-to-core X-ray emission spectroscopy: a study of low-spin octahedral cobalt(iii) complexes. Dalton Transactions 45:14191–14202. https://doi.org/10.1039/c6dt02413k
• Kiser PD, Farquhar ER, Shi W, et al (2012) Structure of RPE65 isomerase in a lipidic matrix reveals roles for phospholipids and iron in catalysis. Proceedings of the National Academy of Sciences 109:. https://doi.org/10.1073/pnas.1212025109
• England J, Martinho M, Farquhar ER, et al (2009) A Synthetic High-Spin Oxoiron(IV) Complex: Generation, Spectroscopic Characterization, and Reactivity. Angewandte Chemie 121:3676–3680. https://doi.org/10.1002/ange.200900863
• Wang D, Farquhar ER, Stubna A, et al (2009) A diiron(iv) complex that cleaves strong C–H and O–H bonds. Nature Chemistry 1:145–150. https://doi.org/10.1038/nchem.162
• Emerson JP, Kovaleva EG, Farquhar ER, et al (2008) Swapping metals in Fe- and Mn-dependent dioxygenases: Evidence for oxygen activation without a change in metal redox state. Proceedings of the National Academy of Sciences 105:7347–7352. https://doi.org/10.1073/pnas.0711179105
• Farquhar ER, Richard JP, Morrow JR (2007) Formation and Stability of Mononuclear and Dinuclear Eu(III) Complexes and Their Catalytic Reactivity Toward Cleavage of an RNA Analog. Inorganic Chemistry 46:7169–7177. https://doi.org/10.1021/ic7005666