The Department of Chemistry and Physics continues its Spring Seminar series. Details for our upcoming talk are given below.
Grote Hall Room 411
Luis Sanchez Diaz, PhD, Assistant Professor of Physics, University of Tennessee at Chattanooga
Viscoelasticity Of Bacteria: E. Coli and the Antibiotic Response
Multidrug resistant bacteria are currently one of the most serious public health threats. In view of the increasing shortage of available therapies efficient against bacterial strains which have adapted and developed numerous resistance mechanisms, new strategies are needed. One method to identify bacteria resistance is through cell stiffness. Several studies with AFM (Atomic Force Microscope) have focused on how antibiotic exposure alters cellular membrane rigidity, through determining the elasticity of ampicillin resistant strains of E. coli over several generations grown in increasing concentrations of antibiotic. Challenges for this technique include the difficulty of isolating single cells, as well as the scanning time required to locate a single bacteria cell. An alternative method to study the stiffness of the cell is through rheology. The change of stiffness at the cellular level will manifest as collective behavior changing the shear stress, viscosity, and shear modulus. While the rheology of bacterial suspensions has been measured in several studies, the effect of antibiotic resistance on the rheology of bacterial suspensions has not been sufficiently explored. Here, by using a rheometer and in combination with AFM, we expect that our methodology and procedures will bring new insights to the bacteria’s response to a well-known bacteriolytic antibiotic.