Helicobacter pylori is a widespread Gram-negative bacterium that infects the
stomach of humans leading to the onset of several gastric disorders, such as, gastritis,
gastric ulcers, and cancers. Studies from developing countries with low socioeconomic
status and poor management of the drinking water suggest that it may serve as an
environmental reservoir of H. pylori and therefore contribute to human infection.
It has been reported that H. pylori has the ability to form microbial consortia
embedded by a highly hydrated exopolysaccharidic matrix (biofilms) on surfaces
exposed to water. The enhanced protection provided to microbial cells by the
exopolysaccharides (EPS) brings added concerns about the possibility of H. pylori
being transmitted through drinking water. H. pylori EPS as been reported to be
composed mainly by Gal:Glc:GlcN in a proportion of 1.0:2.1:7.0, respectively (Stark et
al., 1999).
The present work brings about microscopical evidences of the capability of H.
pilory to form free swimming bacterial aggregates and biofilms when submitted to
nutrient depletion and hydrodynamic stress. Evidences that H. pylori aggregation is an
exopolysaccharidic mediated phenomena both in planktonic and sessile states are also
showed. Ethanol fractioning of the material recovered from these aggregates revealed an
EPS composed of Gal:Glc:GlcN in a proportion of 1.0:0.4:1.6 respectively. A further
structural detail about this EPS is under progress
