Liz Karr, Ph.D.
Department of Botany/Microbiology
University of Oklahoma
770 Van Vleet Oval
Norman, OK 73019
Office: 516 GLCH
Lab: 505 GLCH
Phone: 405-325-5133
E-mail: lizkarr@ou.edu
2003–2007 NSF Postdoctoral Fellow, The Ohio State University, Department of Microbiology
1999 - 2003 Ph.D. student, Southern Illinois University, Carbondale, Department of Microbiology
Research Interests
My primary research interests involve the interactions between microorganisms and their environment, in understanding how microorganisms survive, respond, and thrive under different and changing environmental conditions. Of particular interest is the thermophile Methanothermobacter thermoautotrophicus (Mt). Mt is an anaerobic obligatory autotrophic methanogen and a member of the archaeal domain. It’s environmentally important and sole metabolism along with transcription mechanisms based on both eukaryotic and bacterial components make it an ideal organism in which to study transcription level regulation in response to ever changing environmental conditions.
Publications
Karr, E. A., K. Sandman, L. Cubonova, A. Cochran, and J.N. Reeve. In preparation.TrpY regulation of trpB2 transcription in vitro from Methanothermobacter thermautotrophicus.
Cubonova, L., K. Sandman, E. A. Karr, A. Cochran, and J.N. Reeve. Submitted. Mutational Analysis of the archaeal regulator TrpY. J. Bac.
Karr, E. A., W. M. Sattley, S. M. Belchik, M.T. Madigan, and L. A. Achenbach. 2006. Biodiversity of methanogenic and other Archaea in the permanently frozen Lake Fryxell, Antarctica. Appl. Environ. Microbiol. 72: 1663-1666.
Madigan, M. T., D. O. Jung, E. A. Karr, W. M. Sattley, L. A. Achenbach, and M. van der Meer. 2005. Diversity of anoxygenic phototrophs in contrasting extreme environments. In: Geothermal Biology and Geochemistry in Yellowstone National Park. W. Inskeep (ed). Thermal Biology Institute, Montana State University.
Karr, E. A., W. M. Sattley, M. R. Rice, D. O. Jung, M. T. Madigan, and L. A. Achenbach. 2005. Diversity and distribution of sulfate-reducing bacteria in the permanently frozen Lake Fryxell, McMurdo Dry Valleys, Antarctica. Appl. Environ. Microbiol. 71: 6353-6359.
Jung, D. O., L. A. Achenbach, E. A. Karr, S. Takaichi, and M. T. Madigan. 2004. A gas vesiculate planktonic strain of the purple nonsulfur bacterium Rhodoferax antarcticus isolated from Lake Fryxell, Dry Valleys, Antarctica. Arch. Microbiol. 182: 236-243.
Karr, E. A., W. M. Sattley, D. O. Jung, M. T. Madigan, and L. A. Achenbach. 2003. Remarkable diversity of phototrophic purple bacteria in a permanently frozen Antarctic lake. Appl. Environ. Microbiol. 69: 4910-4914.
Graduate Research
Molecular Analyses of the Biodiversity and Metabolic State of Sulfur-Cycling Prokaryotes in Lake Fryxell, Antarctica
In conjunction with Laurie Achenbach and Mike Madigan in the Department of Microbiology at SIUC I studied bacteria that live in Lake Fryxell, Antarctica. Lake Fryxell is located in the McMurdo Dry Valleys, an area representing a small percentage of the Antarctic continent not covered by ice. Lake Fryxell has a permanent ice cover of several meters and beneath this ice water is present. This water provides an environment for bacteria to live, although they must be able to survive in the harsh environment of the Antarctic. We are interested in three different groups of bacteria that live in Lake Fryxell. The first group anoxygenic phototrophs that obtain the energy they need to live through photosynthesis. The other two groups of bacteria produce energy by sulfate reduction and sulfur oxidation. In order to focus specifically on these groups of organisms, metabolic genes essential to their energy gaining processes are targeted. The use of molecular tools such as denaturing gradient gel electrophoresis (DGGE), DNA sequencing, and cDNA analysis allow us to examine the overall diversity of these organisms in Lake Fryxell and understand their contributions to the inorganic sulfur cycle.
