Premium
Microbial Metabolism in Ice and Brine at −5°C
Author(s) -
Bakermans Corien,
Skidmore Mark L.
Publication year - 2011
Publication title -
environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.954
H-Index - 188
eISSN - 1462-2920
pISSN - 1462-2912
DOI - 10.1111/j.1462-2920.2011.02485.x
Subject(s) - brine , biology , psychrophile , incubation , nutrient , glacier , metabolism , food science , biochemistry , environmental chemistry , chemistry , ecology , paleontology , organic chemistry , enzyme
Summary Metabolic activity, but not growth, has been observed in ice at temperatures from −5°C to −32°C. To improve understanding of metabolism in ice, we simultaneously examined various aspects of metabolism ( 14 C‐acetate utilization, macromolecule syntheses and viability via reduction of CTC) of the glacial isolates Sporosarcina sp. B5 and Chryseobacterium sp. V3519‐10 during incubation in nutrient‐rich ice and brine at −5°C for 50 days. Measured rates of acetate utilization and macromolecule syntheses were high in the first 20 days suggesting adjustment to the lower temperatures and higher salt concentrations of both the liquid vein network in the ice and the brine. Following this adjustment, reproductive growth of both organisms was evident in brine, and suggested for Sporosarcina sp. B5 in ice by increases in cell numbers and biomass. Chryseobacterium sp. V3519‐10 cells incubated in ice remained active. These data indicate that neither low temperature nor high salt concentrations prohibit growth in ice, but some other aspect of living within ice slows growth to within the detection limits of current methodologies. These results imply that microbial growth is plausible in natural ice systems with comparable temperatures and sufficient nutrients, such as debris‐rich basal ices of glaciers and ice masses.