Rachael Morgan-Kiss

Rachael Morgan-Kiss

Associate Professor of Micro­biology

Office:
Phone:
Email:
URL:
98 Pearson Hall
(513) 529-5434
morganr2@MiamiOH.edu
photopsychrophile.weebly.com

Education:

Ph.D., University of Western Ontario, 2000

Research Interests:

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

Lipid Bodies in an Antarctic algae isolate (Chlamydomonas ICE sp.)

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, Fryxell 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/).

Current Projects

Culture-Based Research

  1. Environmental adaptation of the enzyme RubisCO in cold adapted microalgae.
  2. Oxidative stress response in psychrophilic microorganisms.
  3. Effect of temperature on circadian response in temperate and cold adapted microalgae.
  4. Acclimation of microalgae to variable carbon and energy sources under low temperatures.
  5. Development of low temperature tolerant microalgal strains as biofuel producers.

Field Research

  1. Adaptation of microbial communities during the shift from 24 hr daylight to darkness during the polar night transition in ice-covered Antarctic lakes.
  2. Diversity of autotrophic microorganisms in chemically stratified Antarctic lakes.
  3. Quantitative real-time PCR detection of functional genes in aquatic communities.
  4. Diversity and trophic function of microbial eukaryotes in oligotrophic (Antarctic) versus eutrophic (Ohio) lakes.
  5. Enrichment and isolation of autotrophic organisms from Antarctic lakes.

Recent Publications

(* undergraduate student author; ** graduate student author)

  • Kong W., Li W., Prášil O., Romancova I., Morgan-Kiss R.M. (2014) An integrated study of photochemical function and expression of a key photochemical gene (psbA) in photosynthetic communities of Lake Bonney (McMurdo Dry Valleys, Antarctica). FEMS Microbiology Ecology (in press).
  • Raymond J.A., Morgan-Kiss R.M. (2013) Separate origins of ice-binding proteins in Antarctic Chlamydomonas species. PLoS One 8: e59186.
  • Dolhi J.M.**, Maxwell D., Morgan-Kiss R.M. (2013) The Antarctic Chlamydomonas raudensis: an emerging model for cold adaptation of photosynthesis. Extremophiles 17: 711-722.
  • Kong W., Dolhi J.**, Chiuchiolo A., Priscu J.C., Morgan-Kiss R.M. (2012) Evidence of form II RubisCO (cbbM) in a perennially ice-covered Antarctic lake. FEMS Microbiology Ecology Special Issue: Polar and Alpine Microbiology 82:491-500
  • Kong W., Ream D.*, Priscu J.C., Morgan-Kiss R.M. (2012) Diversity and expression of RubisCO genes in a perennially ice-covered Antarctic lake during the polar night transition. Applied Environmental Microbiology 78:4358-4366.
  • Dolhi J.**, Ketchum N.*, Morgan-Kiss R.M. (2012) Use of carbon fixation potential as a measure of metabolic versatility between phototrophic and mixotrophic enrichment cultures isolated from a chemically stratified Antarctic lake. Journal of Visual Experiments 62:e3992
  • 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 Journal 5: 1559-1564.