Comparative Analysis of Ionic Strength Tolerance between Freshwater and Marine Caulobacterales Adhesins

Most bacteria spend a large part of their life spans attached to surfaces, forming complex multicellular communities called biofilms. Bacteria can colonize virtually any surface, and therefore, they have adapted to bind efficiently in very different environments. In this study, we compare the adhesive holdfasts produced by the freshwater bacteriumC. crescentus and a relative, the marine bacteriumH. baltica . We show thatH. baltica holdfasts have a different morphology and chemical composition and tolerate high ionic strength. Our results show that theH. baltica holdfast is an excellent model to study the effect of ionic strength on adhesion and provides insights into the physicochemical properties required for adhesion in the marine environment.