Effects of DNP on the cell surface properties of marine bacteria and its implication for adhesion to surfaces

Abstract

The effect of 2, 4-dinitrophenol (DNP) on extracelluar polysaccharides (EPS), cell surface charge, and hydrophobicity of six marine bacterial cultures was studied, and its influence on attachment of these bacteria to glass and polystyrene was evaluated. Interestingly, after DNP treatment there was a significant decrease in the hydrophobicity of both hydrophobic (p = 0.01) and hydrophilic (p = 0.05) cultures, whereas no significant change was observed in the cell surface charge and EPS production of these cultures. DNP treatment resulted in significant reduction in the attachment of all the six cultures to glass (p = 0.02) and polystyrene (p = 0.03). Moreover, hydrophobicity but not the cell surface charge and EPS production, influenced bacterial cells attachment to glass and polystyrene. From this study, it was evident that DNP treatment influenced bacterial cell surface hydrophobicity, which in turn, reduced bacterial adhesion to surfaces.