Pseudomonas aeruginosa Forms Biofilms in Acute Infection Independent of Cell-to-Cell Signaling

Departments of Surgery, Microbiology and Immunology Pathology, and Cell Biology and Biochemistry Texas Tech University Health Sciences Center, 3601 4^th St., Lubbock, Texas, 79430, USA; Life Sciences Division, Lawrence Berkley National Laboratory, 1 Cyclotron Road, Berkley, California, 94720; Department of Bioengineering, Rice University, 6100 Main, Houston, Texas, 77005; Department of Biological Sciences, Auburn University, 319 Life Sciences Building, Auburn, Alabama, 36849

^* To whom correspondence should be addressed. Email: kendra.rumbaugh{at}ttuhsc.edu.

	Abstract

Biofilms 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 aeruginosa forms biofilms within 8 hours 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. aeruginosa biofilms 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. aeruginosa formed similar biofilms in vivo. Our findings demonstrate that P. aeruginosa forms biofilms on specific host tissues independent of QS.