Oxidative Stress Protection and the Repair Response to Hydrogen Peroxide in the Hyperthermophilic Archaeon Pyrococcus furiosus and in Related Species

Document Type

Article

Publication Date

6-1-2010

Abstract

Pyrococcus furiosus is a shallow marine, anaerobic archaeon that grows optimally at 100 degrees C. Addition of H(2)O(2) (0.5 mM) to a growing culture resulted in the cessation of growth with a 2-h lag before normal growth resumed. Whole genome transcriptional profiling revealed that the main response occurs within 30 min of peroxide addition, with the up-regulation of 62 open reading frames (ORFs), 36 of which are part of 10 potential operons. More than half of the up-regulated ORFs are of unknown function, while some others encode proteins that are involved potentially in sequestering iron and sulfide, in DNA repair and in generating NADPH. This response is thought to involve primarily damage repair rather than protection, since cultures exposed to sub-toxic levels of H(2)O(2) were not more resistant to the subsequent addition of H(2)O(2) (0.5-5.0 mM). Consequently, there is little if any induced protective response to peroxide. The organism maintains a constitutive protective mechanism involving high levels of oxidoreductase-type enzymes such as superoxide reductase, rubrerythrin, and alkyl hydroperoxide reductase. Related hyperthermophiles contain homologs of the proteins involved in the constitutive protective mechanism but these organisms were more sensitive to peroxide than P. furiosus and lack several of its peroxide-responsive ORFs.

Publication Title

Archives of Microbiology

Volume

192

Issue

6

First Page

447

Last Page

459

PubMed ID

20379702

Comments

This article was published in Archives of Microbiology, Volume 192, Issue 6, June 2010, Pages 447-59.

The published version is available at http://dx.doi.org/10.1007/s00203-010-0570-z

Copyright © 2010 Springer, Part of Springer Science+Business Media

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