Polar Microbiology, Physiology, and Ecology
My laboratory is interested in the environmental adaptations that allow microorganisms to thrive in extreme habitats. Permanently low temperature ecosystems represent some of the most poorly understood extremophilic habitats in the world, despite the extraordinary biological diversity and global importance of these regions. To date, there are few representative microbial models from cold environments and efforts to link the physiology and biochemistry of polar microbes with the molecular mechanisms governing adaptation have been limited. Thus, the overall goals for my research program are to establish laboratory models of cold-adapted autotrophic microorganisms and to exploit functional genomic and molecular biology based approaches to identify how microorganisms are genetically adapted to their unique niches. My current research program encompasses two areas of research: I) physiological adaptation of extremophilic autotrophic organisms, and II) diversity and function of microorganisms from extreme environments. We apply these research themes to integrated questions that link cultured-based studies under controlled laboratory conditions with field-based research on the microbial communities residing in their natural environments. Our main study sites are chemically stratified, permanently ice-capped lakes located in the McMurdo Dry Valleys, Antarctica.
McMurdo Dry Valley Field Seasons
2008 - [NSF0631659] This multi-investigator project proposed to study lakes within the Taylor Valley during the transition to polar night to test the overarching hypothesis that the onset of darkness induces a cascade of physiological changes that alters the functional roles of autotrophic and heterotrophic microplankton within the lakes. The overarching hypothesis of this project was: Polar night induces a cascade of physiological changes that alters the functional role of autotrophic and heterotrophic microplankton within the lakes. Work in the Morgan-Kiss laboratory specifically addressed two sub-hypotheses: Functional downregulation of the photochemical apparatus during the summer-winter transition is integral to the overwintering strategy of phytoplankton; the photosynthetic process will be structurally altered at the level of gene expression in phototrophic communities during the winter-summer transition. (for complete details see: http://openwetware.org/wiki/IPY)
2010 - This past season our laboratory focused on gaining a better understanding of the diversity and activity of autotrophic communities residing in three of the Taylor Dry Valley lakes (Lakes Bonney, Frxyell and Vanda). Experiments in the field included collection of lake water for molecular analyses as well as enzymatic assays, as well as setting up enrichments cultures for isolating new microorganisms adapted to different nutritional requirements. Our hypotheses for this project are: Lake-specific variations in abiotic factor(s) control distribution and functional gene expression of key phototrophic protists; Energy/carbon acquisition in dry valley lake phototrophic protists is adapted to lake-specific variations in environmental niche. (2010 field season blog: http://mcmdryvalleys.blogspot.com/).
- Environmental adaptation of the enzyme RubisCO in cold adapted microalgae.
- Oxidative stress response in psychrophilic microorganisms.
- Effect of temperature on circadian response in temperate and cold adapted microalgae.
- Acclimation of microalgae to variable carbon and energy sources under low temperatures.
- Development of low temperature tolerant microalgal strains as biofuel producers.
- Adaptation of microbial communities during the shift from 24 hr daylight to darkness during the polar night transition in ice-covered Antarctic lakes.
- Diversity of autotrophic microorganisms in chemically stratified Antarctic lakes.
- Quantitative real-time PCR detection of functional genes in aquatic communities.
- Diversity and trophic function of microbial eukaryotes in oligotrophic (Antarctic) versus eutrophic (Ohio) lakes.
- Enrichment and isolation of autotrophic organisms from Antarctic lakes.
Publications; 2006-present(* undergraduate student author; ** graduate student author)
- Morgan-Kiss R.M. and Dolhi J.D.** (2011) Microorganisms and Plants: a Photosynthetic Perspective. In: Storey, K. & Tanino, K. [Eds.] Nature at Risk: Temperature in a Changing Climate. CABI 2010 Invited Chapter. 20 pp. In review.
- Kong W., Ream D.C.*, Priscu J.C., Morgan-Kiss R.M. (2011) RubisCO lineages in a perennially ice-covered Antarctic lake during the polar night transition. Proc. Natl. Acad. Sci. USA. Submitted.
- Feasel P.*, Dolhi J.**, Hanson T.E., Morgan-Kiss R.M. (2011) Low temperature adaptation of Ribulose-1,5-bisphosphate carboxylase/oxygenase in the model photopsychrophile, Chlamydomonas raudensis UWO241 (CHLOROPHYCEAE, CHLOROPHYTA). Phycologia. Submitted.
- Bielewicz S.*, Kong W., Bell E., Priscu J.C., Morgan-Kiss R.M. (2011) Influence of polar night transition on the diversity of protists in Lake Bonney, a permanently ice-covered Antarctic lake. ISME J In press.
- Hanson T.E., Morgan-Kiss R.M., Chan L.K., Hiras J. (2010) Beyond the genome: functional studies of phototrophic sulfur oxidation. Advances in Experimental Medicine and Biology. 675: 109-121.
- Jiang Y., Morgan-Kiss R.M., Campbell J., Chan, C.H., Cronan, J. (2010) Expression of Vibrio harveyi Acyl-ACP synthetase allows entry of exogenous fatty acids into the Escherchia coli fatty acid and lipid A synthetic pathways. Biochemistry. 49:718-726
- Kiss A.J., Devries A.L., Morgan-Kiss R.M. (2010) Comparative analysis of crystallins and lipids from the lens of Antarctic toothfish and cow. J Comp Physiol B 180:1019-1032
- Jaraula C.M.B., Brassell S.C., Morgan-Kiss R.M., Doran P.T., Kenig F. (2010) Tentative identification of pentaunsaturated alkenones from Lake Fryxell, East Antarctica. Org Geochem 41:386-397.
- Chan, L.K., Morgan-Kiss R.M., Hanson T.E. (2009). Functional analysis of three sulfide:quinone oxidoreductase homologs in Chlorobaculum tepidum. J Bacteriol 191, 1026-1034.
- Morgan-Kiss R.M., Chan L.K., Weber T.S., Modla S. Czymmek K., Hanson T.E. (2009) Chlorobaculum tepidum regulates chlorosome structure and function in response to temperature and electron donor availability. Photosynth. Res. 99:11-21.
- Morgan-Kiss R.M., Cronan J.E. (2008) The Lactococcus lactis FabF fatty acid synthetic enzyme can functionally replace both the FabB and FabF proteins of Escherichia coli and the FabH protein of Lactococcus lactis. Archiv Microbiol 190: 427-437.
- Chan L.K., Weber T.S., Morgan-Kiss R.M., Hanson T.E. (2008) A genomic region required for phototrophic thiosulfate oxidation in the green sulfur bacterium Chlorobium tepidum (syn. Chlorobaculum tepidum). Microbiology-Sgm 154: 818-829.
- Morgan-Kiss R.M., Ivanov A.G., Modla S., Czymmek K., Huner N.P.A., Priscu J.C., Lisle J.T., Hanson T.E. (2008) Identity and physiology of a new psychrophilic eukaryotic green alga, Chlorella sp., strain BI, isolated from a transitory pond near Bratina Island, Antarctica. Extremophiles 12: 701-711.
- Gudynaite-Savich L., Gretes M., Morgan-Kiss R.M., Savich L.V., Simmonds J.., Kohalmi S.E., Huner N.P.A. (2006) Cytochrome f from the Antarctic psychrophile, Chlamydomonas raudensis UWO241: structure, sequence, and complementation in the mesophile, Chlamydomonas reinhardtii. Molec. Genet. Genom. 275(4): 387-398.
- Morgan-Kiss R.M., Priscu JC, Pocock T, Gudnaite-Savich L., Huner NPA (2006) Adaptation and acclimation of photosynthetic microorganisms to permanently cold environments. Microbiol. Molec. Biol. Rev. 70:222-252.