Paleobiological significance of hydrophobicity and adhesion of phototrophic bacteria from microbial mats

Abstract

The characterization is carried out of cell–surface hydrophobicity and adhesion to quartz, calcite and magnetite by Enthophysalis, Microcoleus, Synechococcus and Chromatium (phototrophic bacteria from microbial mats of Hamelin Pool, Shark Bay, W. Australia). The study confirms the great variation in ability of the bacteria to adhere to n-hexadecane, polystyrene and octyl-Sepharose, according to physiological conditions. The bacteria studied show binding to the mineral surfaces independent of the degree of hydrophobicity of the cell surface. The status of the factors and mechanisms that explain Precambrian microfossil formation is discussed. Considering the scant attention paid to the role of the original chemistry of the living cells in their preservation as microfossils, cell–surface hydrophobicity, adhesion to solid surfaces and the development of bacterial biofilms are proposed as physiological characteristics that allow the preservation of cyanobacterial soft cells as Precambrian microfossils.