Deep-sea hydrothermal vents: a new source of innovative bacterial exopolysaccharides of biotechnological interest?

Polysaccharides and, in particular, microbial polysaccharides represent a class of important products of growing interest for many sectors of industry. Although many known marine bacteria produce exopolysaccharides (EPS), continuation in looking for new polysaccharide-producing microorganisms is promising. Hydrothermal deep-sea vents could be a source of novel EPS as indicated by the screening of a number of mesophilic heterotrophic bacteria recovered from different locations. Although originating from such extreme environment, some bacteria were shown to biosynthesize innovative EPS under laboratory conditions. Their specific rheological properties either in the presence or absence of monovalent and divalent ions, biological activities, metal binding capabilities, and novel chemical composition mean that these EPS are expected to find many applications in the near future.