Status of methods for assessing bacterial cell surface charge properties based on zeta potential measurements

Surface interfacial physiology is particularly important to unicellular org anisms with regard to maintenance of optimal cell function, Bacterial cell surfaces possess net negative electrostatic charge by virtue of ionized pho sphoryl and carboxylate substituents on outer cell envelope macromolecules which are exposed to the extracellular environment. The degree of periphera l electronegativity influences overall cell surface polarity and can be ass essed on the basis of zeta potential which is most often determined by esti mating the electrophoretic mobility of cells in an electric field. The purp ose of this review is to provide bacteriologists with assistance as they se ek to better understand available instrumentation and fundamental principle s concerning the estimation of zeta potential as it relates to bacterial su rface physiology. (C) 2001 Elsevier Science B.V. AV rights reserved.