Archives of Microbiology

, Volume 180, Issue 6, pp 498–502

Compensatory increase in ahpC gene expression and its role in protecting Burkholderia pseudomallei against reactive nitrogen intermediates

  • Suvit Loprasert
  • Ratiboot Sallabhan
  • Wirongrong Whangsuk
  • Skorn Mongkolsuk
Original Paper

DOI: 10.1007/s00203-003-0621-9

Cite this article as:
Loprasert, S., Sallabhan, R., Whangsuk, W. et al. Arch Microbiol (2003) 180: 498. doi:10.1007/s00203-003-0621-9

Abstract

In the human pathogen Burkholderia pseudomallei, katG encodes the antioxidant defense enzyme catalase-peroxidase. Interestingly, a B. pseudomallei mutant, disrupted in katG, is hyperresistant to organic hydroperoxide. This hyperresistance is due to the compensatory expression of the alkyl hydroperoxide reductase gene (ahpC) and depends on a global regulator OxyR. The KatG-deficient mutant is also highly resistant to reactive nitrogen intermediates (RNI). When overproduced, the B. pseudomallei AhpC protein, protected cells against killing by RNI. The levels of resistance to both organic peroxide and RNI returned to those of the wild-type when the katG mutant was complemented with katG. These studies establish the partially overlapping defensive activities of KatG and AhpC.

Keywords

MelioidosisAlkyl hydroperoxide reductaseCatalase-peroxidase

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Suvit Loprasert
    • 1
  • Ratiboot Sallabhan
    • 1
  • Wirongrong Whangsuk
    • 1
  • Skorn Mongkolsuk
    • 1
    • 2
  1. 1.Laboratory of BiotechnologyChulabhorn Research InstituteBangkok 10210Thailand
  2. 2.Department of Biotechnology, Faculty of ScienceMahidol UniversityBangkok 10400Thailand