Karen L. Koster, Professor

Ph.D. (Plant Physiology) Cornell University, 1991
B.S. (Organismal Biology) University of Kansas, 1984



Department of Biology
The University of South Dakota
414 E. Clark Street
Vermillion, SD 57069
Phone: 1-605-677-6173
Fax: 1-605-677-6557
E-mail: Karen.Koster@usd.edu

Office: Churchill-Haines Labs 168D
Lab: Churchill-Haines Labs 182A

Research Interests

Physcomitrella patens

My research focuses on understanding the responses of plants to environmental stress, in particular extreme water loss. Some organisms are desiccation tolerant, a fundamental biological adaptation that allows these organisms to avoid environmental conditions that might otherwise be lethal, such as episodes of freezing or high temperature. Research in my lab centers on trying to elucidate mechanisms by which cells in these organisms survive dehydration. We use two systems for most of our studies: angiosperm seeds and the moss Physcomitrella patens (shown at right). Experiments are conducted at multiple levels of complexity, including whole organisms, isolated cells and protoplasts, and model membranes, to understand the processes that occur during drying and rehydration of desiccation-tolerant and -sensitive organisms. Results of these studies may help us understand how organisms survive drying.

I also do research on seed longevity, which is dependent upon processes that occur in the dried tissues. Understanding the physical and chemical changes that occur in dehydrated cells may help us improve the longevity of seeds and other genetic resources when they are stored.

Fall 2016 Courses

  • Cell Biology


    Selected Publications

    Koster, K.L., R.A. Balsamo, C. Espinoza, M.J. Oliver. 2010. Desiccation sensitivity and tolerance in the moss Physcomitrella patens: assessing limits and damage. Plant Growth Regulation 62: 293-302. DOI: 10.1007/s10725-010-9490-9

    Oliver, M.J., J.C. Cushman, K.L. Koster. 2010. Dehydration tolerance in plants. (Review) in R Sunkar, ed. Plant Stress Tolerance, Methods in Molecular Biology, 639: 3-24. Springer-Verlag. DOI: 10.1007/978-1-60761-702-0_1

    Lenné, T., C.J. Garvey, K.L. Koster, G. Bryant. 2010. Kinetics of the lamellar gel-fluid transition in phosphatidylcholine membranes in the presence of sugars. Chemistry and Physics of Lipids 163: 236-242. DOI: 10.1016/j.chemphyslip.2009.12.001

    Lenné, T.; C.J. Garvey, K.L. Koster, G. Bryant. 2009. The effects of sugars on lipid bilayers during dehydration: SAXS/WAXS measurements and quantitative model. Journal of Physical Chemistry B 113: 2486-2491. DOI: 10.1021/jp808670t

    Walters, C., K.L. Koster. 2007. Structural dynamics and desiccation damage in plant reproductive organs. in M.A. Jenks, A. Wood, eds., Plant Desiccation Tolerance, Blackwell Publishing, Inc. Oxford, U.K. ISBN: 9780813812632.

    Lenné, T., G. Bryant, R. Holcomb, K.L. Koster. 2007. How much solute is needed to inhibit the fluid-gel membrane phase transition at low hydration? Biochimica et Biophysica Acta - Biomembranes 1768: 1019-1022.

    Halperin, S.J., K.L. Koster. 2006. Sugar effects on membrane damage during desiccation of pea embryo protoplasts. Journal of Experimental Botany 57: 2303-2311.

    Mo B., K.L. Koster. 2006. Changes in lipoxygenase isoforms during germination and early seedling growth of Pisum sativum L. Seed Science Research 16: 97-106.

    Koster, K.L. and G. Bryant. 2006. Dehydration in model membranes and protoplasts: contrasting effects at low, intermediate and high hydrations. in T.H.H. Chen, M. Uemura, S. Fujikawa, eds., Cold Hardiness in Plants, CABI, Wallingford, UK. pp. 219-234.

    Goodman, B.E., K.L. Koster, P.L. Redinius. 2005. Comparing biology majors from large lecture classes with TA-facilitated laboratories to those from small lecture classes with faculty-facilitated laboratories. Advances in Physiology Education 29: 112-117.

    Hejl, A.M. and K.L. Koster. 2004. The allelochemical sorgoleone inhibits root H+-ATPase and water uptake. Journal of Chemical Ecology 30: 2181-2191.

    Bryant, G. and K.L. Koster. 2004. Dehydration of solute-lipid systems: Hydration forces analysis. Colloids & Surfaces B: Biointerfaces 35: 73-79.

    Hejl, A.M. and K.L. Koster. 2004. Juglone disrupts root plasma membrane H+-ATPase activity and impairs water uptake, whole leaf photosynthesis, root respiration, and growth in soybean (Glycine max) and corn (Zea mays). Journal of Chemical Ecology 30: 453-471.

    Koster, K.L., N. Reisdorph, and J.L. Ramsay. 2003. Changing desiccation tolerance of pea embryo protoplasts during germination. Journal of Experimental Botany 54: 1607-1614.

    Koster, K.L., K.J. Maddocks, and G. Bryant. 2003. Exclusion of maltodextrins from phosphatidylcholine multilayers during dehydration: effects on membrane phase behaviour. European Biophysics Journal 32: 96-105.

    Ramsay, J. and K.L. Koster. 2002. A comparison of anhydrous fixation methods for the observation of pea embryonic axes (Pisum sativum L. cv Alaska). Seed Science Research 12: 83-90.

    Wolfe, J., G. Bryant, and K.L. Koster. 2002. What is 'unfreezable water', how unfreezable is it and how much is there? Cryo-Letters 23: 157-166.

    Xiao, L. and K.L. Koster. 2001. Desiccation tolerance of protoplasts isolated from pea embryos. Journal of Experimental Botany 52: 2105-2114.

    Bryant, G., K.L. Koster, and J. Wolfe. 2001. Membrane behaviour in seeds and other systems at low water content: the various effects of solutes. Seed Science Research 11: 17-25.

    Koster, K.L., Y.P. Lei, M. Anderson, S. Martin, and G. Bryant. 2000. Effects of vitrified and non-vitrified sugars on phosphatidylcholine fluid-to-gel phase transitions. Biophysical Journal 78: 1932-1946.

    Koster, K.L., M.S. Webb, G. Bryant, and D.V. Lynch. 1994. Interactions between soluble sugars and POPC (1-palmitoyl-2-oleoyl-phosphatidylcholine) during dehydration: vitrification of sugars alters the phase behavior of the phospholipid. Biochimica et Biophysica Acta 1193: 143-150.

    Koster, K.L. 1991. Glass formation and desiccation tolerance in seeds. Plant Physiology 96: 302-304.

    Koster, K.L. and A.C. Leopold. 1988. Sugars and desiccation tolerance in seeds. Plant Physiology 88: 829-832.

    To see more of Dr. Koster's publications, please see these additional items.
    The views and opinions expressed in these pages are strictly those of Karen L. Koster. The content of these pages has not been reviewed or approved by The University of South Dakota.
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