Biolog metabolic fingerprints for clustering marine oligotrophic bacteria from polar regions
Oligotrophic bacteria from the Western Greenland Sea (Expedition ARKTIS IV/2, 1987) have been isolated by enrichment culture techniques in dialysis chambers or by continuous-flow of seawater through nylon or glass-fibre filter in double Petri dishes. The isolated strains appeared to be Gram-negative and psychrotrophic. Organic substrate utilizations of 52 strains were determined in Biolog microplates for Gram-negatives and the obtained metabolic fingerprints used for clustering the bacteria. Three distinct clusters can be recognized at the 80% similarity level, as recommended by the Biolog company.These bacteria were compared with 55 oligotrophic isolates from the Gunnerus and Astrid Ridge, Antarctic Ocean (Expedition ANTARKTIS VIII/6, 1990). From the five clusters found among the Antarctic bacteria, two were the same as two clusters from the Arctic. These identical groups of bacteria from the north and south polar regions will be the subject of phylogenetic investigations to study the strategies of cold adaptations in bacteria.
ANT > VIII > 6