Adherence of Pseudomonas aeruginosa elastase deficient mutant

Pseudomonas aeruginosa produces several extracellular substances such as enzymes and toxins which seem to contribute to its pathogenicity. In particular, alkaline protease and elastase production seems to affect bacterial adherence. Aim of this study was to isolate an elastase deficient mutant of P. aeruginosa and to demonstrate a possible correlation between enzyme production and adherence to WEHI cells. Mutant strain showed a significant reduction of elastase and protease alkaline activity, as the decrease of absorbance values demonstrate. Furthermore the adherence to WEHI cells of mutant strain was strongly reduced with respect to the wild strain. Our results prove that proteolytic enzymes play an important role in adherence, probably modifying the cell surfaces and so enhancing adherence.