Anaerobic regulation by an atypical Arc system in Shewanella oneidensis
Abstract
Shewanella oneidensis strain MR-1 is well known for its respiratory versatility, yet little is understood about how it regulates genes involved in anaerobic respiration. The Arc two-component system plays an important role in this process in Escherichia coli; therefore, we determined its function in S. oneidensis. arcA from S. oneidensis complements an E. coli arcA mutant, but the Arc regulon in S. oneidensis constitutes a different suite of genes. For example, one of the strongest ArcA-regulated gene clusters in E. coli, sdh, is not regulated by the Arc system in S. oneidensis, and the cyd locus, which is induced by ArcA in E. coli under microaerobic conditions, is repressed by ArcA in S. oneidensis under anaerobic conditions. One locus that we identified as being potentially regulated by ArcA in S. oneidensis contains genes predicted to encode subunits of a dimethyl sulphoxide (DMSO) reductase. We demonstrate that these genes encode a functional DMSO reductase, and that an arcA mutant cannot fully induce their expression and is defective in growing on DMSO under anaerobic conditions. While S. oneidensis lacks a highly conserved full-length ArcB homologue, ArcA is partially activated by a small protein homologous to the histidine phosphotransfer domain of ArcB from E. coli, HptA. This protein alone is unable to compensate for the lack of arcB in E. coli, indicating that another protein is required in addition to HptA to activate ArcA in S. oneidensis.
Additional Information
© 2005 Blackwell Publishing Ltd. Accepted 21 February, 2005. Article first published online: 31 MAR 2005. We thank Doug Lies, Curtis Callan and Arash Komeli for helpful discussions. J.A.G. was supported through a Texaco Postdoctoral Scholarship awarded through the Caltech Division of Geological and Planetary Sciences. C.T.B. was supported by National Institutes of Health Grant GM61005 to E.H. Davidson. We thank E.H. Davidson and R.A. Cameron of the Beckman Institute Center for Computational Regulatory Genomics at Caltech for access to their computational resources (supported by National Institutes of Health Grant RR15044). Grant support from the Office of Naval Research, the Luce Foundation and the Packard Foundation to D.K.N. is gratefully acknowledged.Attached Files
Supplemental Material - MMI_4628_sm_TableS1.doc
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Additional details
- Eprint ID
- 24894
- DOI
- 10.1111/j.1365-2958.2005.04628.x
- Resolver ID
- CaltechAUTHORS:20110816-135040019
- Texaco Postdoctoral Scholarship
- NIH
- GM61005
- Office of Naval Research (ONR)
- Henry Luce Foundation
- David and Lucile Packard Foundation
- Created
-
2011-09-15Created from EPrint's datestamp field
- Updated
-
2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences