The role of cell-bound flocculants in coflocculation of benthic cyanobacteria with clay particles

The benthic filamentous cyanobacteria Phormidium J-1 and Anabaenopsis circularis 6720 adsorbed suspended clay particles and coflocculated with them. Coflocculation was correlated with production of extracellular flocculants. In old cultures there was a decrease in both coflocculating activity and cell surface hydrophobicity. It is proposed that attachment to the benthos is facilitated by the common action of both coflocculation and hydrophobic interactions. A simultaneous decrease in these two surface characteristics enables the cells to detach and colonize new surfaces.