PARTICULATE DIMETHYLSULFOXIDE IN ARCTIC SEA‐ICE ALGAL COMMUNITIES: THE CRYOPROTECTANT HYPOTHESIS REVISITED

• Published in: Journal of Phycology
• Main Authors: Lee, Peter A., De Mora, Stephen J., Gosselin, Michel, Levasseur, Maurice, Bouillon, René‐Christian, Nozais, Christian, Michel, Christine
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2001
• Subjects: Baffin Bay; Baffin; ice algae; Phytoplankton; Sea ice
• Online Access: http://dx.doi.org/10.1046/j.1529-8817.2001.037004488.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1529-8817.2001.037004488.x; https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1529-8817.2001.037004488.x

The particulate‐phase concentrations of dimethyl sulfoxide (DMSO p ) and dimethylsulfoniopropionate (DMSP p ) in sea‐ice algal communities from the North Water, northern Baffin Bay, were examined from April to June 1998. The concentrations of these compounds were measured in the bottom 2 cm of the ice at 36 locations throughout this region and are compared with results from water‐column samples collected for a complementary study. In general, levels of DMSP p (8.66–987 nmol·L − 1 , average 126 nmol·L − 1 ) in sea‐ice algal communities were slightly less than those found in bottom sea‐ice algal communities from other polar locations but greater than those found in phytoplankton in other polar environments or at more temperate latitudes. Furthermore, DMSP p :chl a ratios (0.02–14.8 nmol·μg − 1 , average 1.91 nmol·μg − 1 ) in the sea‐ice algal community were slightly less than those found in other polar environments. DMSO p was measured for the first time in sea‐ice algal communities. DMSO p concentrations varied from 1.35 to 102 nmol·L − 1 (average 13.7 nmol·L − 1 ). DMSO p :chl a ratios varied from 0.01 to 4.5 nmol·μg − 1 (average 0.22 nmol·μg − 1 ) and were significantly lower than the DMSP p :chl a ratios observed in this study. It has been hypothesized that DMSO can act as a cryoprotector in phytoplankton cells. However, the low concentrations of DMSO observed in the ice algae during this study indicate that intracellular concentrations of DMSO are unlikely to have a significant influence on the freezing point depression of intracellular fluids.