Alginate production by clinical nonmucoid Pseudomonas aeruginosa strains

The slime material from a revertant nonmucoid variant, derived by serial passage of a heavily mucoid Pseudomonas aeruginosa strain isolated from a patient with bacteremia, was found to contain 16% uronic acids, 48.5% carbohydrates, 11% protein, and 2% lipids. Chromatographic analysis by ion exchange chromatography revealed that this extracellular material consisted of three fractions, one uronic acid fraction with properties similar to those of the alginate fraction of the parental strain and two other fractions consisting of neutral sugars and proteins in approximately a 5:1 ratio. In addition, the slime material from six other clinical macroscopic nonmucoid P. aeruginosa strains was found to contain alginate. These results demonstrate that alginate production in various amounts is a property shared by all P. aeruginosa strains.