Researchers from the University of Washington, Seattle and the University of Alaska Fairbanks have found bacterial activity in arctic wintertime sea ice and may attribute its survival to particle or surface attachment. Their findings appear in the January 2004 issue of the journal Applied and Environmental Microbiology.
Previous studies pertaining to bacterial activity in sea ice have been conducted during the "warm" sunlit season with results drawn from melted ice. In this study, samples of arctic sea ice were collected from Alaska during winter months and maintained at subzero temperatures while being tested for bacterial activity of Cytophaga-Flavobacteria-Bacteriodes (CFB) and Archea. Researchers found the existence of CFB and Archea in wintertime sea ice to be largely associated with attachment to surface particles, with the percentage of attachment increasing as temperatures decreased.
"We have identified in this study one possible strategy for continued bacterial activity in wintertime sea ice: association with particles or surfaces," say the researchers. "The observation of active bacteria at 20 degrees celcius suggests that wintertime sea ice is more than a refugium for temporarily preserved life and brings the discussion of limits of life on Earth to a different level."
(K. Junge, H. Eicken, J.W. Deming. 2004. Bacterial activity at 2 to 20 in arctic wintertime sea ice, 70. 1: 550-557.)
NEW TEST OFFERS FASTER DETECTION OF CONTAMINATED OYSTERS
Researchers from the University of Alabama at Birmingham have developed a new DNA-based test that allows for rapid detection of contaminated oysters. Their findings appear in the January 2004 issue of the journal Applied and Environmental Microbiology.