Document Type


Date of Award

Spring 5-8-2020



First Advisor

Dr. Karin Sauer

Second Advisor

Dr. Cláudia Marques

Third Advisor

Dr. Susan Bane


Science and Mathematics

Subject Heading(s)

Glucose-6-phosphate dehydrogenase; Proteins; Biofilms; Pseudomonas aeruginosa


The SagS protein is a two-component regulatory system in Pseudomonas aeruginosa that works to independently regulate biofilm formation and antibiotic tolerance. Previous work found that these two pathways are controlled by two distinct sets of amino acids within the sensory domain of SagS that are thought to be potential ligand binding sites. Despite the extensive research done on the structure and function of SagS, the signals that activate this protein have yet to be identified. In this study we aimed to identify ligands that stimulate SagS-dependent biofilm formation. To do this we utilized ΔsagS mutants, one harboring wild-type sagS under the control of its native promoter and the other harboring the empty vector, attachment assays and COMSTAT analysis. Initially, we found that Mn2+ stimulates SagS-dependent attachment, but not SagS-dependent biofilm formation. While we ultimately identified D-glucose-6-phosphate as a ligand that enhances SagS-dependent biofilm formation. These findings provide a better understanding of how SagS works to control biofilm formation in P. aeruginosa and points to potential new method for treating P. aeruginosa infections.

Included in

Biology Commons