Leptospira interrogans catalase is required for resistance to H2O2 and for virulence

Azad Eshghi, Kristel Lourdault, Gerald Laurence Murray, Thanatchaporn Bartpho, Rasana Sermswan, Mathieu Picardeau, Ben Adler, Brendan Snarr, Richard L Zuerner, Caroline E Cameron

Research output: Contribution to journalArticleResearchpeer-review

53 Citations (Scopus)

Abstract

Pathogenic Leptospira spp. are likely to encounter higher concentrations of reactive oxygen species induced by the host innate immune response. In this study, we characterized Leptospira interrogans catalase (KatE), the only annotated catalase found within pathogenic Leptospira species, by assessing its role in resistance to H(2)O(2)-induced oxidative stress and during infection in hamsters. Pathogenic L. interrogans bacteria had a 50-fold-higher survival rate under H(2)O(2)-induced oxidative stress than did saprophytic L. biflexa bacteria, and this was predominantly catalase dependent. We also characterized KatE, the only annotated catalase found within pathogenic Leptospira species. Catalase assays performed with recombinant KatE confirmed specific catalase activity, while protein fractionation experiments localized KatE to the bacterial periplasmic space. The insertional inactivation of katE in pathogenic Leptospira bacteria drastically diminished leptospiral viability in the presence of extracellular H(2)O(2) and reduced virulence in an acute-infection model. Combined, these results suggest that L. interrogans KatE confers in vivo resistance to reactive oxygen species induced by the host innate immune response.
Original languageEnglish
Pages (from-to)3892 - 3899
Number of pages8
JournalInfection and Immunity
Volume80
Issue number11
DOIs
Publication statusPublished - 2012

Cite this