Pseudomonas aeruginosaForms Biofilms in Acute Infection Independent of Cell-to-Cell Signaling

ABSTRACTBiofilms are bacterial communities residing within a polysaccharide matrix that are associated with persistence and antibiotic resistance in chronic infections. We show that the opportunistic pathogen Pseudomonas aeruginosaforms biofilms within 8 h of infection in thermally injured mice, demonstrating that biofilms contribute to bacterial colonization in acute infections as well. Using light, electron, and confocal scanning laser microscopy, P. aeruginosabiofilms were visualized within burned tissue surrounding blood vessels and adipose cells. Although quorum sensing (QS), a bacterial signaling mechanism, coordinates differentiation of biofilms in vitro, wild-type and QS-deficient P. aeruginosastrains formed similar biofilms in vivo. Our findings demonstrate that P. aeruginosaforms biofilms on specific host tissues independently of QS.