*Indicates presenter, undergraduates, and REU students from the Karr lab are underlined.
To see a list of seminars and conference presentations, click here.
To see a list of publications, click here.
S. Yaghoubi*, D.M. Dinh, LM. Thomas, N.Q. Wofford, M.J. McInerney, E. A. Karr. Structural characterization of an enzyme responsible for energy conservation in a model syntrophic organism. Poster Presented at OU Graduate Student Life Research Day, March 3, 2023.
D.M. Dinh*, S. Yaghoubi, L.M. Thomas, M.J. McInerney, E.A. Karr. 3-D structure of an enzyme responsible for energy production in a model syntroph. West Coast Bacterial Physiologists. December 17, 2022. (virtual)
D.M. Dinh, S. Yaghoubi, L.M. Thomas, N.Q. Wofford, M.J. McInerney, and E.A. Karr*. Electron Flow and Energy Conservation in Syntrophic Metabolism. Poster presented at the 2022 DOE Basic Energy Sciences Physical Biosystems PI Meeting. (virtual)
D.M. Dinh.*, L.M. Thomas, E. Moore, M.J. McInerney, and E. A. Karr. “Characterization of enzymes involved in substrate metabolism and energy production in Synthrophus aciditrophicus strain SB”. West Coast Bacterial Physiologists Annual Asilomar Conference, December 12, 2020 (virtual)
D.M. Dinh*, L.M. Thomas, N.Q. Wofford, E. Moore, M.J. McInerney, and E. A. Karr. Initial structure solution of 3-oxopimelyl-CoA thiolase (Act1) and the activities of bidirectional enzymes from Syntrophus aciditrophicus . 7th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 6, 2019.
Moore, E.*, D.M. Dinh, M.J. McInerney, and E. A. Karr. Purification and crystallization of recombinant 3-oxypimelyl-CoA thiolase from Syntrophus aciditrophicus. OU Honors College Four Year Research Experiences for Undergraduates program poster session. May 2019.
Moghe, R.*, D.M. Dinh, M.J. McInerney, and E.A. Karr. Overexpression and purification of recombinant acetyl-CoA synthetase from Syntrophus aciditrophicus. OU Honors College Four Year Research Experiences for Undergraduates program poster session. May 2018.
Koshy, R.A.*, D.M. Dinh, M.J. McInerney, and E.A. Karr. Optimizing the purity of recombinant acetyl-CoA synthetase from Syntrophus aciditrophicus. OU NSF REU in Structural Biology Poster Session. July 27, 2017.
Dinh, D.M.*, M.J. McInerney, and E.A. Karr. Purification and crystal screening of acetyl-CoA synthetase from Syntrophus aciditrophicus. 5th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 15, 2017.
Hebdon, S.*, S. Menon, J. Sykes, G.B. Richter-Addo, E.A. Karr, and A.H. West. Elucidating the structure and a putative transcriptional regulon of response regulator RR_1586 from Clostridium difficile R20291. 5th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 15, 2017.
Hebdon, S.*, S. Menon*, J. Sykes, G.B. Richter-Addo, E.A. Karr, and A.H. West. Structure-function studies of a response regulator of unknown function from hypervirulent Clostridium difficile R20291. Bacterial Locomotion and Signal Transduction (BLAST XIV), New Orleans, January 15-20, 2017.
Chanderban, M.*, and E.A. Karr. Functional analysis of a two-component system in a methanogen. Louis Stokes Midwest Center for Excellence Annual Meeting for Louis Stokes Alliances for Minority Participation Scholars, September 2016.
Malone, H.*, V. Trinh, and E.A. Karr. Functional analysis of methanogen hybrids. OU NSF REU in Structural Biology Poster Session. July 28, 2016.
Chanderban, M.*, C.E. Isom, P.C. Bourne, A.H. West, G.B. Richter-Addo, and E.A. Karr. Elucidating the role of YtrA-like transcription regulators in hypervirulent Clostridium difficile. OU Summer Undergraduate Research Symposium, July 28, 2016.
Karr, E.A.*, K. Shelton, K. Gilcrest, V. Trinh. The novel transcription regulator, MsvR, from methanogenic archaea. NIH, NIGMS 6th Biennial National IDeA Symposium of Biomedical Research Excellence (NISBRE). Washington, DC June 26-28, 2016.
Chanderban, M.*, C.E. Isom, P.C. Bourne, A.H. West, G.B. Richter-Addo, and E.A. Karr. Elucidating the role of YtrA-like transcription regulators in hypervirulent Clostridium difficile. 4th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 14, 2016.
Shelton, K.*, V. Trinh, C.E. Isom, K. Gilcrest, M. Chanderban and E.A. Karr. Characterization of the Methanosarcina acetivorans MsvR family protein. 4th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 14, 2016.
Powell, S.M.*, B. Wang, N. Hessami, F. Najar, L.M. Thomas, A.H. West, E.A. Karr, and G.B. Richter-Addo. Crystal structures of two FMN-dependent nitroreductases from a hypervirulent strain of C. difficile. 4th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 14, 2016.
Hebdon, S.*, J. Sykes, S. Menon, F. Najar, E.A. Karr, G.B. Richter-Addo, and A.H. West. Gene transcription regulated by two-component response regulators in a hypervirulent strain of Clostridium difficile. 4th Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 14, 2016.
Cheng, M.*, C.E. Isom, and E.A. Karr. Development and understanding of the GntR1351 transcription regulator in Clostridium difficile. OU Honors College First Year Research Experiences for Undergraduates program poster session. April 2016.
*Shelton, K., C.E. Isom, V. Trinh, K. Gilcrest, J. Lee, and E.A. Karr. Structure and function analysis of the redox-sensing transcription factor Methanogen Specific Vinyl-4-Reductase (MsvR), ASM Regional Missouri Valley Branch Meeting. March 4-5, 2016.
Jennings, M.E.*, F. H. Lessner, E. A. Karr, and D. J. Lessner. The ferredoxin-like domain and [4Fe-4S] clusters of subunit D play important roles in RNAP assembly and activity in Methanosarcina acetivorans. Poster presentation at the Gordon Research Conference entitled Archaea: Ecology, Metabolism, and Molecular Biology. Newry, Maine; July 2015.
Shelton, K. K.*, C.E. Isom, V. Trinh, K. Gilcrest, J. Lee, and E.A. Karr. Structure and function analysis of the redox-sensing transcription factor MsvR. 3rd Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 8, 2015.
Isom, C.E.*, S. Menon, L.M. Thomas, A.H. West, G. B. Richter-Addo, and E. A. Karr. Crystal structure of the transcription regulator PadR from hyper-virulent Clostridium difficile. 3rd Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 8, 2015.
Wang, B.* N. Hesami, L.M. Thomas, A.H. West,1 E.A. Karr, and G.B Richter-Addo. Crystal structure of an FMN-binding nitroreductase from Clostridium difficile. 3rd Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 8, 2015.
Menon, S.*, F. Najar, K. Soni, J. Sykes, E.A. Karr, G.B Richter-Addo, and A. H. West. Structure-function characterization of response regulator proteins from Clostridium difficile, a major cause of healthcare-associated infections (HAIs). 3rd Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 8, 2015.
Jennings, M.E.*, F.H. Lessner, E.A. Karr, and D. J. Lessner. Investigation of the role [4Fe-4S] clusters play in RNA polymerase formation and function in Methanosarcina acetivorans. Poster position presented at Iron-Sulfur Enzymes Gordon Research Conference. Easton, MA June 16-20, 2014.
Folkerts, M., C.E. Isom, and E.A. Karr*. The role of the MsvR regulatory domain in function. NIH, NIGMS 5th Biennial National IDeA Symposium of Biomedical Research Excellence (NISBRE). Washington, DC June 16-18, 2014.
Folkerts, M.*, C.E. Isom, and E.A. Karr. The role of the MsvR regulatory domain in function. 2nd Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, June 2014.
James, K.L.*, L.A. Rios-Hernandez, N. Wofford, H. Mouttaki, J.R. Sieber, C.S. Sheik, E.A. Karr, Y. Yang, Y. Xie, L. Rohlin, J.A. Loo, R.R. O. Loo, R.P. Gunsalus, and M.J. McInerney. A mechanism for substrate-level phosphorylation in the syntrophic fatty and aromatic acid degrader, Syntrophus aciditrophicus. Poster session presented at the 114th General Meeting of the American Society of Microbiology, Boston, MA, May 2014.
Isom, C.E., M. Folkerts, D.J. Lessner, and E.A Karr*. Insights into the MsvR protein family. Poster presentation at the Gordon Research Conference entitled Archaea: Ecology, Metabolism, and Molecular Biology. Lucca, Italy; July 2013.
Jennings, M.E.*, F.H. Lessner, E.A. Karr, and D.J. Lessner. Investigation of the role [4Fe-4S] clusters play in RNA polymerase formation and function in Methanosarcina acetivorans. Poster session presented at the 113th General Meeting of the American Society of Microbiology, Denver, CO. May 18-21, 2013.
Isom, C.E.*, and E.A. Karr. The MsvR homologue of Methanosarcina acetivorans C2A is a dimeric regulator whose function, on is modulated by cysteine residues. 1st Annual Symposium on Structural Biology, Oklahoma COBRE in Structural Biology, May 2013.
Karr, E.A.*, J.L. Turner, and D.J. Lessner. Characterization of the Methanosarcina acetivorans C2A MsvR homologue and comparisons to Methanothermobacter thermautotrophicus. Poster presentation at the Gordon Research Conference entitled Archaea: Ecology, Metabolism & Molecular Biology Waterville Valley Resort, NH July 2011.
Turner, J.L.*, and E.A. Karr. Mutational analysis of key amino acid residues in a transcriptional regulator of an oxidative stress response operon in Methanothermobacter thermautotrophicus. Poster session presented at the 110th General Meeting of the American Society of Microbiology, San Diego, CA. May 23-27, 2010.
Karr, E.A.*, K. Sandman, R. Lurz, and J.N. Reeve. TrpY regulation of trpB2 transcription in vitro from Methanothermobacter thermautotrophicus. Poster session presented at the Archaea Gordon Conference, Andover, NH, August 19-24, 2007.
Karr, E.A.*, K. Sandman, L. Cubonova, A. Cochran, and J.N. Reeve. TrpY regulation of trpB2 transcription in vitro from Methanothermobacter thermautotrophicus. Poster session presented at Extremophiles 2006, Brest, France, September 17-21, 2006.
Madigan, M.T.*, D. O. Jung, E.A. Karr, W.M. Sattley, L.A. Achenbach, and M. van der Meer. The diversity of Anoxygenic Phototrophs in contrasting extreme environments. Abstract for the First Biannual Geothermal Biology Workshop, Yellowstone National Park, WY, October 9-11, 2003.
Jung, D.O., W.M. Sattley, E.A. Karr, L.A. Achenbach, and M.T. Madigan*. New extremophilic phototrophic bacteria including purple nonsulfur bacteria containing gas vesicles. Poster session presented at the 11th International Symposium on Phototrophic Prokaryotes, Tokyo, Japan, August 24-29, 2003.
Karr, E.A.*, J.M. Ng, S.M. Belchik, and L.A. Achenbach. Molecular analysis of the biodiversity of Archaea in Lake Fryxell, Antarctica. Poster session presented at the 103rd General Meeting of the American Society of Microbiology, Washington, D.C. May 18-23, 2003.
Jung, D.O.*, D.B. Nichols, E.A. Karr, L.A. Achenbach, and M.T. Madigan. A gas-vesiculate purple nonsulfur bacterium from Lake Fryxell, Antarctica. Poster session presented at the 103rd General Meeting of the American Society of Microbiology, Washington, D.C., May 18-23, 2003.
Sattley, W.M.*, E.A. Karr, L.A. Achenbach, and M.T. Madigan. Cold-active sulfate-reducing and sulfur chemolithotrophic bacteria from Lake Fryxell, Dry Valleys, Antarctica. Poster session presented at the 103rd General Meeting of the American Society of Microbiology, Washington, D.C., May 18-23, 2003.
Madigan, M.T.*, E.A. Karr, D.O. Jung, W.M. Sattley, and L.A. Achenbach. Extremophilic phototrophic and sulfur-cycling prokaryotes from permanently frozen Antarctic lakes and African soda lakes. Poster session presented at the NSF-Microbial Observatories/Life in Extreme Environments Workshop, Washington, D.C., September 23-24, 2002.
Karr, E.A.*, M.T. Madigan, and L.A. Achenbach. Molecular analyses of the biodiversity and metabolic state of sulfate-reducing bacteria in Lake Fryxell, Antarctica. Poster session presented at the 102nd Annual Meeting of the American Society for Microbiology, Salt Lake City, Utah, May 2002.
Karr, E.A.*, M.T. Madigan, and L.A. Achenbach. Molecular Analyses of the Biodiversity and metabolic state of sulfur-cycling prokaryotes in Lake Fryxell, Antarctica. Eighth Annual Molecular and Cellular Biology Symposium, Grafton, IL, March 2002.
Karr, E.A.*, J.R. Carey, M.T. Madigan, and L.A. Achenbach. Biodiversity of anoxygenic phototrophs in permanently frozen Antarctic lakes. Poster session presented at the 101st Annual Meeting of the American Society for Microbiology, Orlando, Florida, May 2001.
Achenbach, L.A., E.A. Karr, J.R. Carey, J.N. Crespi, and M.T. Madigan*. A photosynthesis probe for tracking phototrophic purple bacteria in nature. US-Egypt Workshop on Microbial Ecology, National Research Center, Cairo, Egypt, May 2001.
