Unusual Microbial Exopolysaccharides from Hydrothermal Deep-sea Origin
Jean GUEZENNEC*a, Martine LOAECb, and Helene ROUGEAUXc
a IFREMER. Centre de Brest. Dept DRV/VP/BMH. BP 70. 29280 Plouzane
b UBO Avenue Le Gorgeu, BP 809.29287. Brest (France)
c Groupe EVEN Traon Bihan, BP60 29262. BREST Cedex
In recent years there has been a growing interest in the isolation and identification of new marine microbial polysaccharides that might have applications in many sectors of the industry. A deep-sea, aerobic, mesophilic and heterotrophic bacterium was isolated from fluid collected nearby an active hydrothermal vent. On the basis of phenotypical and phylogenetic analyses and DNA/DNA relatedness, this strain could be assigned to the species Alteromonas macleodii as a new sub-species. The structure of the exopolysaccharide produced by this bacterium under lab conditions was investigated. By means of chemical analysis and NMR studies, the repeating unit of the polymer was deduced to be a branched hexasaccharide. Besides other interesting properties, this unusual exopolysaccharide showed a significant ability to bind heavy metals in solution. Binding maximum capacity as high as 316 mg Pb(II) / g polymer indicates that it may have potential for use in applications in waste water treatment and biodetoxification of heavy metal polluted water.
