Bacterial adhesion and metabolic activity: Investigation of the link between the charge-regulated nature of the bacterial cell surface and cellular bioenergetics

Lehigh University, Bethlehem PA

Investigators

Abstract

CBET- 0828356 Brown, Derick Lehigh University Bacterial adhesion and metabolic activity: Investigation of the link between the charge-regulated nature of the bacterial cell surface and cellular bioenergetics The principal objective of this proposal is to investigate the effect of bacterial adhesion to surfaces on metabolic activity, and to develop a predictive model of how the properties of a surface will affect Äp and cellular ATP levels of adhered bacteria. The research hypothesis is that there is a direct link between bacterial adhesion and the proton motive force that forms across the bacterial membrane, with the result being a shift in the pH at the cell surface. The project incorporates both microbial biology techniques and numerical modeling to study the impact of bacterial adhesion, surface properties, and divalent concentration on bacterial cellular energetics. It is anticipated that this study will show (1) that there is a direct link between bacterial adhesion to a surface and changes to Äp; (2) that these changes to Äp are due to a shift in pH at the cell surface upon adhesion; and (3) that these changes to Äp will be a function of the bacterial and solid surface properties and multivalent cation concentration in the bulk solution, as predicted by the charge regulation effect. If the hypothesis is shown to be true, this will open up a spectrum of new research areas in microbiology and microbial ecology (e.g., understanding how cells make use of this enhanced Äp and ATP, such as altering cellular growth yields or initiating other processes upon adhesion, such as cell signaling and production of extracellular polymers for biofilm formation), and environmental engineering, bioengineering and materials science (e.g., engineered design and application of surfaces to achieve desired enhancements or reductions in metabolic activity, such as with bioreactors, medical devices and implants, and pipelines). A key component of this project is the integration of research with education by involving graduate, undergraduate and high school students.