Karen Junge

Currently, Karen Junge’s research interests lie at the interface of the biosphere and geosphere where she explores bacterial life at extremely low temperatures in ice. She is motivated by research questions that center around how polar psychrophilic (cold-loving) bacteria adapt to life in ice and how they interact with and impact their physical and chemical environment, questions that currently comprise a very active research field. To this end, she develops and uses molecular biology, microbiology, geophysics and atmospheric science techniques. She is also interested in the genomic makeup of these organisms and molecular adaptations to the cold life style and how physiology, diversity and ecology of psychrophilic bacteria change when confronted with the extreme cold. She is driven to develop ways to analyze microbial communities under in-situ conditions with minimal disturbance of their natural environment.

Karen Junge heads the Polar Microbiology group within the Polar Science Center.

• Gentilhomme, A. S., Dhakar, K., Timmins-Schiffman, E., Chaw, M., Firth, E., Junge, K., & Nunn, B. L. (2025). Proteomic Insights into Psychrophile Growth in Perchlorate-Amended Subzero Conditions: Implications for Martian Life Detection. Astrobiology. https://doi.org/10.1089/ast.2024.0065

• Ewert, M., Nunn, B. L., Firth, E., & Junge, K. (2025). Metabolic Responses, Cell Recoverability, and Protein Signatures of Three Extremophiles: Sustained Life During Long-Term Subzero Incubations. Microorganisms, 13(2), 251. https://doi.org/10.3390/microorganisms13020251

• Ni Z, Arevalo R Jr, Bardyn A, Willhite L, Ray S, Southard A, Danell R, Graham J, Li X, Chou L, Briois C, Thirkell L, Makarov A, Brinckerhoff W, Eigenbrode J, Junge K, Nunn BL. (2023). Detection of Short Peptides as Putative Biosignatures of Psychrophiles via Laser Desorption Mass Spectrometry. Astrobiology, 23(6), 657-669. PubMed PMID: 37134219. https://doi.org/10.1089/ast.2022.0138. 
   

• Mudge, M.C., Nunn, B.L., Firth, E., Ewert, M., Hales, K., Fondrie, W.E., Noble, W.S., Toner, J., Light, B., and Junge, K.A. (2021), Subzero, saline incubations of Colwellia psychrerythraea reveal strategies and biomarkers for sustained life in extreme icy environments. Environ Microbiol, 23: 3840-3866, doi:10.1111/1462-2920.15485.

• Frantz, C.M., Light, B., Farley, S.M., Carpenter, S., Lieblappen, R., Courville, Z., Orellana, M.V., and Junge, K.: Physical and optical characteristics of heavily melted “rotten” Arctic sea ice, The Cryosphere, 13, 775-793, doi:10.5194/tc-13-775-2019, 2019.
   

• Junge, K., Cameron, K. and Nunn, B., 2019. Diversity of Psychrophilic Bacteria in Sea and Glacier Ice Environments—Insights Through Genomics, Metagenomics, and Proteomics Approaches. In Microbial Diversity in the Genomic Era (pp. 197-216). Academic Press. https://doi.org/10.1016/B978-0-12-814849-5.00012-5

• Nunn, B.L., K. Slattery, K. A. Cameron, E. Timmins-Schiffman, and K. Junge. 2015. Proteomics of Colwellia psychrerythraea at subzero temperatures – a life with limited movement, flexible membranes and vital DNA repair. Environmental Microbiology. 111, 9009-9014.

• Cameron, K.A., B. Hagedorn, M. Dieser, B.C. Christner, K. Choquette, R. Sletten, B. Crump, C. Kellogg, and K. Junge. 2015. Diversity and potential sources of microbiota associated with snow on western portions of the Greenland Ice Sheet. Environmental Microbiology, 17:594-609.

• Dieser, M., E.L.J.E. Broemsen, K.A. Cameron, G.M. King, A. Achberger, K. Choquette, B. Hagedorn, R. Sletten, K. Junge, and B.C. Christner. 2014. Molecular and biogeochemical evidence for methane cycling beneath the western margin of the Greenland Ice Sheet. ISME Journal, 8:2305-2316.

• Junge, K., B.C. Christner, and J.T. Staley, “Diversity of Psychrophilic Bacteria from Sea Ice – and Glacial Ice Communities“. In K. Horikoshi, G. Antranikian, A. Bull, F. Robb, and K. Stetter (eds), Extremophiles Handbook. Springer, Heidelberg, Germany. 1247 pp, 2011.

• Skidmore, M., Jungblut, Anne, and Urschel, M. and K. Junge., “Cryospheric Environments in Polar regions (Glaciers and Ice Sheets, Sea Ice, Ice Shelves).”, In Polar Microbiology. L.Whyte and R. Miller (eds). ASM Press., (2011), Accepted.

• Junge, K., and B.D. Swanson,’ High-resolution ice nucleation spectra of sea-ice bacteria: Implications for cloud formation and life in frozen environments‘, Biogeosciences Discussion, 4, 4261-4282, 2008.

• Mock, T. and K. Junge, “Psychrophilic Diatoms: Mechanisms for Survival in Freeze-thaw cycles”, Algae and Cyanobacteria in Extreme Environments, Springer Netherlands; DOI10.1007/978-1-4020-6112-7, pp. 343 to 364, 2007.

• M.L. Laucks, A. Sengupta, K. Junge, E.J. Davis and B.D. Swanson. “Comparison of psychro-active Arctic marine bacteria and common mesophilic bacteria using surface-enhanced raman spectroscopy”. Appl. Spectroscopy 10: 1222-1228, 2006.

• K. Junge, H. Eicken, B. D. Swanson and, J. W. Deming. “Bacterial incorporation of leucine into protein down to –20°C with evidence for potential activity in subeutectic saline ice formations”. Cryobiol. 52: 417–429, 2006.

• Deming, J. W. and K. Junge. ‘‘Colwellia’’, in The Proteobacteria, Part B, Bergey’s Manual of Systematic Bacteriology, G. T. Staley, D. J. Benner, N. R. Krieg, and G. M. Garrity, Eds. (Springer, New York, 2005), 2nd., Vol. 2, pp. 447–454, 2005.

• Junge, K., H. Eicken, and J. W. Deming. A Microscopic Approach to Investigate Bacteria under In-Situ Conditions in Arctic Lake Ice: Initial Comparisons to Sea Ice. In Bioastronomy 2002: Life Amongst the Stars IAU Symposium 213, eds. R. Norris and F. Stootman. Astronomical Society of the Pacific, San Francisco: 381-388, 2004.

• Junge, K., H. Eicken, and J. W. Deming. “Bacterial activity at -20°C in Arctic wintertime sea ice“. Appl. Environ. 70: 550-557, 2004.

• Junge, K., H. Eicken, and J. W. Deming. “Motility of Colwellia psychrerythrea str. 34H observed at subzero temperatures“. Appl. Environ. Microbiol. 69: 4282–4284, 2003.

• Junge, K., J.F. Imhoff, J.T. Staley and J.W. Deming, “Phylogenetic diversity of numerically important Arctic sea-ice bacteria cultured at subzero temperature”, Microb. Ecol. 43: 315-328, 2002.

• Krembs, C., H. Eicken, K. Junge, and J. W. Deming, “High concentrations of exopolymeric substances in wintertime sea ice: Implications for the polar ocean carbon cycle and cryoprotection of diatoms“, Deep-Sea Res. I 9: 2163 –2181, 2002.

• Skoog, A. K. Whitehead, F. Sperling, and K. Junge, “Microbial glucose uptake and growth along a horizontal nutrient gradient in the North Pacific“, Limnol. Oceanogr., 47(6):1676–1683, 2002.

• Staley, J. T, K. Junge, and J. Deming. And some like it cold: sea ice microbiology. In Biodiversity of Life, eds. J. T Staley and A.-L. Reysenbach, pp. 423-438, 2001.

• Junge, K., C. Krembs, J. Deming, A. Stierle and H. Eicken, “A microscopic approach to investigate bacteria under in situ conditions in sea-ice samples“, Ann. Glaciol. 33: 304-310, 2001.

• Junge K, J. J. Gosink, H.-G. Hoppe and J. T. Staley. Arthrobacter, Brachybacterium and Planococcus isolates identified from Antarctic sea ice brine. Description of Planococcus mcmeekenii, sp. nov. Syst Appl Microbiol 21: 306-314, 1998.