This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Google Scholar
Right arrow Articles by Burns, J. L.
Right arrow Articles by DiChristina, T. J.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Burns, J. L.
Right arrow Articles by DiChristina, T. J.
Agricola
Right arrow Articles by Burns, J. L.
Right arrow Articles by DiChristina, T. J.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, August 2009, p. 5209-5217, Vol. 75, No. 16
0099-2240/09/$08.00+0     doi:10.1128/AEM.00888-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Anaerobic Respiration of Elemental Sulfur and Thiosulfate by Shewanella oneidensis MR-1 Requires psrA, a Homolog of the phsA Gene of Salmonella enterica Serovar Typhimurium LT2{triangledown} ,{dagger}

Justin L. Burns and Thomas J. DiChristina*

School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332

Received 20 April 2009/ Accepted 16 June 2009

Shewanella oneidensis MR-1, a facultatively anaerobic gammaproteobacterium, respires a variety of anaerobic terminal electron acceptors, including the inorganic sulfur compounds sulfite (SO32–), thiosulfate (S2O32–), tetrathionate (S4O62–), and elemental sulfur (S0). The molecular mechanism of anaerobic respiration of inorganic sulfur compounds by S. oneidensis, however, is poorly understood. In the present study, we identified a three-gene cluster in the S. oneidensis genome whose translated products displayed 59 to 73% amino acid similarity to the products of phsABC, a gene cluster required for S0 and S2O32– respiration by Salmonella enterica serovar Typhimurium LT2. Homologs of phsA (annotated as psrA) were identified in the genomes of Shewanella strains that reduce S0 and S2O32– yet were missing from the genomes of Shewanella strains unable to reduce these electron acceptors. A new suicide vector was constructed and used to generate a markerless, in-frame deletion of psrA, the gene encoding the putative thiosulfate reductase. The psrA deletion mutant (PSRA1) retained expression of downstream genes psrB and psrC but was unable to respire S0 or S2O32– as the terminal electron acceptor. Based on these results, we postulate that PsrA functions as the main subunit of the S. oneidensis S2O32– terminal reductase whose end products (sulfide [HS–] or SO32–) participate in an intraspecies sulfur cycle that drives S0 respiration.

* Corresponding author. Mailing address: School of Biology, Georgia Institute of Technology, Atlanta, GA 30332-0230. Phone: (404) 894-8419. Fax: (404) 385-4440. E-mail: thomas.dichristina{at}biology.gatech.edu

{triangledown} Published ahead of print on 19 June 2009.

{dagger} Supplemental material for this article may be found at http://aem.asm.org/.

Applied and Environmental Microbiology, August 2009, p. 5209-5217, Vol. 75, No. 16
0099-2240/09/$08.00+0     doi:10.1128/AEM.00888-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»