Involved in proteolysis and elastolysis (degradation of the host protein elastin). Has staphylolytic activity (degrades pentaglycine cross-links in cell wall peptidogylcan), preferring Gly-Gly-|-X substrates where X is Ala or Gly. Enhances the elastolytic but not proteolytic activity of elastase (lasB) and elastolytic activity of other proteases. Degradation of host elastin is likely to contribute to the pathogenicity of P.aeruginosa. While either His-317 or His-356 can abstract a proton in the hydrolysis reaction, the same residue performs both functions in a given catalytic cycle, with the other stabilizing the catalytic intermediate.

> 90% as determined by SDS-PAGE.