KatA, the Major Catalase, Is Critical for Osmoprotection and Virulence inPseudomonas aeruginosaPA14

Abstract

We demonstrate that among the three monofunctional catalases of Pseudomonas aeruginosa PA14, KatA and, to a lesser extent, KatB, but not KatE, are required for resistance to peroxide and osmotic stresses. KatA is crucial for adaptation to H₂O₂ stress and full virulence in both Drosophila melanogaster and mice. This dismantling of catalase roles represents a specialized catalytic system primarily involving KatA in responses to adverse environmental conditions.