Differential protection from tobramycin by extracellular polymeric substances from Acinetobacter baumannii and Staphylococcus aureus biofilms.

ABSTRACT: We investigated biofilms of two pathogens, Acinetobacter baumannii and Staphylococcus aureus, to characterize mechanisms by which the extracellular polymeric substance (EPS) found in biofilms can protect bacteria against tobramycin exposure. To do so, it is critical to study EPS-antibiotic interactions in a homogeneous environment without mass transfer limitations. Consequently, we developed a method to grow biofilms, harvest EPS, and then augment planktonic cultures with isolated EPS and tobramycin. We demonstrated that planktonic cultures respond differently to being treated with different types of EPS (A. baumannii versus S. aureus) in the presence of tobramycin. By harvesting EPS from the biofilms, we found that A. baumannii EPS acts as a "universal protector" by inhibiting tobramycin

SUBMITTER: Davenport EK 

PROVIDER: S-EPMC4136036 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature