Posts Tagged «Karen Junge»

Naturally produced brominated organic compounds are ubiquitous in the oceans and are thought to be largely responsible for the formation of the Antarctic “ozone hole” in Spring. In order to accurately model and forecast global ozone and the climate, it is critical to include reactive bromine and brominated organic compounds (bromocarbons). However, bromocarbon measurements for the Antarctic are limited, especially during Spring.

This project devises low-temperature liquid-water environments mimicking the known chemistry of brines. The research team measures microbial growth rate, metabolic activity, ability to survive while inactive, and longevity for psychrophiles to reveal proteomic biosignatures for growth, activity, and survival strategies, and understand key molecular responses of life in these environments.

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.

The Arctic Data Center, supported by NSF, has highlighted Karen Junge’s work investigating rotten ice. Data has been collected on both the physical and biological properties of rotten ice and is available from the center.  

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.

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.

This project has two main objectives: 1) determination of the physical and microbial characteristics and microstructural evolution of sea ice exposed to severe melt; and 2) exploration of the influence of biogenic particles such as sea ice algae, bacteria and polymer gels on the melting behavior of sea ice.

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. 

This project characterizes the Greenland Ice Sheet’s subglacial microbial communities to investigate the effect of microbes on lithospheric weathering and nutrient fluxes from the GrIS margin in West Greenland.

In this pilot project (funded through the NASA Exobiology program) our Astrobiology team (PI: Karen Junge, Polar Science Center, APL, UW; postdoc: Ardith Bravenec, UW Earth and Space Science, graduate student Kaitlin Harrison, UW oceanography, both associated with the UW Astrobiology program) will join with the Navy as it conducts its biennial Ice Exercise (ICEX2024 – Operation ICE WHALE) this March (2024, see Fox News video) on sea ice off the coast of Prudhoe Bay, Alaska. We will study how microbes, temperature, and salt content affect the biological and freezing equilibrium signatures of this system with relevance to Enceladus and Europa while also training junior scientists in astrobiology-related field and laboratory work. Liquid water is essential to life as we know it.

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.

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.

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.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.

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., 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. 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.

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.

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.

Karen Junge. 2017. Extreme summer melt: Assessing the habitability and physical structure of rotting first-year Arctic sea ice. Chukchi Sea, Alaska. 2015-2018. Arctic Data Center. doi:10.18739/A28C9R366.

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.

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.  

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.

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.

PI: Karen Junge
Ice is ubiquitous in the Universe. If we better understand how microbial life adapts to Earth ice matrices, we will be in a better position to evaluate and plan tests of the habitability of frozen systems elsewhere in the Universe.

Life as we know it requires liquid water. However Dr. Junge and her collaborators found evidence of ice bacterial protein synthesis to liquid nitrogen temperature (–196°C) when bacterial polymers were present and samples were (likely) vitrified during her postdoc (with Jody Deming and Hajo Eicken) and continuing on with Brian Swanson (New Scientist article).Currently, she is exploring the relationship between this deep-freeze bacterial activity, proteomics, polymers and the physical state of the ice in collaboration with Brook Nunn from the Goodlet laboratory here at the University of Washington and Hajo Eicken at UAF. This collaboration puts them in a unique…

This project will explore the relationship between deep-freeze bacterial activity, proteomics, polymers and the physical state of the ice and will provide important keys to questions regarding life under extreme conditions, be it in the various ice formations here on Earth, the atmosphere or elsewhere in the universe.

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.

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.

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.

In this research project her team is examining the role that bacteria could play in polar atmospheric cloud formation and precipitation processes (on the general topic of bacteria in the atmosphere see: Biological Ice Nucleators.As Co-PI with Brian Swanson from the Laucks Foundation she is investigating whether polar bacteria can interact with ice surfaces via ice nucleation processes. It is known that heterotrophic bacteria play a key role in carbon cycling in polar regions, but little is known about how they interact with their geological material, the ice itself, be it sea-ice, lake ice, glacier ice or ice in the…

The response of Arctic sea ice to a warming climate includes decreases in extent, lower ice concentration, and reduced ice thickness. Summer melt seasons are lengthening with earlier melt onsets and later autumn freezeups. We believe this will likely lead to an increase in so-called “rotten ice” in the Arctic at the end of summer. This ice has experienced a long summer of melt, is fragile, difficult to work with, and has received little attention. Comprehensive information on its physical and microbiological properties does not exist. Our team is embarking on an ambitious field campaign in order to study this poorly-understood type of sea ice in the context of its microstructural properties and potential for habitability.

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.

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.

By developing new microscopy and imaging techniques that allowed for the investigation of sea-ice bacteria within ice without melting it, Karen Junge demonstrated in her PhD research (in collaboration with Jody Deming and Hajo Eicken) that surface associations to ice walls or particles within sea ice are essential for maintenance of activity to –20°C and that psychrophilic bacteria can still be motile to temperatures as low as –10°C moving at similar speeds as Escherichia coli at 37°C.Funding source: NSF, NAI (NASA Astrobiology Institute) through the University of Washington Astrobiology Program.Junge et al., 2001Junge et al., 2002Junge et al., 2003Junge et…