Purchase this article with an account.
M. E. Zegans, J. Lam, C. Toutain-Kidd, J. H. Hammond; Alteration of Lipopolysaccharide Biosynthesis Impacts Polysorbate 80 Mediated Biofilm Inhibition of Pseudomonas aeruginosa. Invest. Ophthalmol. Vis. Sci. 2010;51(13):3900.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Polysorbate 80 (PS80) is a non ionic surfactant which inhibits biofilm formation of Pseudomonas aeruginosa (PA), a leading cause of bacterial corneal infection, at concentrations as low as 0.001%. Since polysorbate 80 is well tolerated on the ocular surface in concentrations of 1% or more, this is a clinically important finding. However, some clinical strains of PA are resistant to PS80 biofilm inhibition. Understanding the basis of PS80 resistance in clinical isolates would be useful in the development of PS80 derivatives as biofilm inhibitors suitable for use on the ocular surface.
All genetic, biochemical and microbiologic assays were performed following previously published protocols. The Pseudomonas aeruginosa _PA14 and PA01 strains are used in all experiments other than those involving clinical isolates. Ocular and non ocular clinical isolates from Dartmouth Medical School and the Campbell Laboratory, University of Pittsburgh were also tested.
Mutation of the algC gene (PA14_23810, PA3116) converts two PS80-resistant strains (lab strain PAO1 and clinical strain PA 738) which are able to form biofilms in the presence of PS80 into strains unable to form biofilms in the presence of PS80. Complementation of these mutants with algC from a plasmidreverted them to the PS80 resistant phenotype. Importantly, PAO1 and PA738 do not over produce lipase or otherwise inactivate PS80 suggesting a novel mechanism of PS80 resistance. Our studies suggests that AlgC is exerting its effect on the PA response to PS80 via its role in the biosynthesis of lipopolysaccaride (LPS) and LPS outer core in particular since mutation of rmlC also produces a similar phenotype.
Our work indicates that modifications of LPS associated with the algC mutation render previously PS80 resistant strains of PA sensitive to PS80 biofilm inhibition. This is likely the result of alteration of direct interactions between PS80 with LPS, or changes access of PS80 to the PA cell membrane. A more detailed study of these interactions should lead to insights into PS80’s effects on PA biofilm biology
This PDF is available to Subscribers Only