Protein and other compositional differences of the extracellular material from slimy and non-slimy colonies of non-mucoid Pseudomonas aeruginosa

The composition of extracellular material produced by non-mucoid strains of Pseudomonas aeruginosa differed when grown on surfaces that either did or did not induce the formation of slime under conditions where the medium was identical. The nature of the changes in protein composition indicated that protein expression differed in the course of growth on the two surfaces, and hence that there were physiological consequences associated with growth under conditions which do or do not lead to slime formation. The compositional differences also included elevated levels in extracellular material from the slimy colonies of two virulence factors, protease and rhamnolipids.