Abstract
The repressor of sulfur-oxidizing (sox) operon regulates expression of genes encoding a multienzyme complex that governs the chemolithotrophic sulfur oxidation in Pseudaminobacter salycylatoxidans KCT001. The inducer of sox operon viz., thiosulfate and other sulfur anions had no impact on in vitro repressor–operator interaction which indicates an atypical derepression mechanism. The reduced repressor has higher affinity for its operator DNA. The sulfur oxidation repressor binds with operator regions and led to efficient repression in trans, however, increased repressor concentration resulted in higher gene expression. Using a reporter system in E. coli, the present study established that the thioredoxin-like protein, encoded in immediate upstream ORF, could nullify the observed reversal of the repression at higher repressor concentration. In this context, the involvement of the upstream gene product in the regulation of the sulfur oxidation gene expression has been reported.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Explore related subjects
Discover the latest articles and news from researchers in related subjects, suggested using machine learning.References
Appia-Ayme C, Berks BC (2002) SoxV, an orthologue of the CcdA disulfide transporter, is involved in thiosulfate oxidation in Rhodovulum sulfidophilum and reduces the periplasmic thioredoxin SoxW. Biochem Biophys Res Commun 296:737–741
Appia-Ayme C, Little PJ, Matsumoto Y, Leech AP, Berks BC (2001) Cytochrome complex essential for photosynthetic oxidation of both thiosulfate and sulfide in Rhodovulum sulfidophilum. J Bacteriol 183:6107–6118
Bardischewsky F, Fischer J, Holler B, Friedrich CG (2006) SoxV transfers electrons to the periplasm of Paracoccus pantotrophus—an essential reaction for chemotrophic sulfur oxidation. Microbiology 152:465–472
Bardischewsky F, Friedrich CG (2001) The shxVW locus is essential for oxidation of inorganic sulfur and molecular hydrogen by Paracoccus pantotrophus GB17: a novel function for lithotrophy. FEMS Microbiol Lett 202:215–220
Bullock WO, Fernandez JM, Short JM (1987) XL1-Blue: a high efficiency plasmid transforming recA Escherichia coli strains with beta-gatactosidase selection. Bio Techniques 5:376–378
Carius Y, Rother D, Friedrich CG, Scheidig AJ (2009) The structure of the periplasmic thiol-disulfide oxidoreductase from Paracoccus pantotrophus indicates a triple Trx/Grx/DsbC functionality in chemotrophic sulfur oxidation. Acta Cryst D65:229–240
Friedrich CG (1998) Physiology and genetics of sulfur-oxidizing bacteria. Adv Microb Physiol 39:235–289
Friedrich CG, Quentmeier A, Bardischewsky F, Rother D, Kraft R, Kostka S, Prinz H (2000) Novel genes coding for lithotrophic sulfur oxidation of Paracoccus pantotrophus GB17. J Bacteriol 182:4677–4687
Jain S, Kaushal D, Dasgupta SK, Tyagi AK (1997) Construction of shuttle vectors for genetic manipulation and molecular analysis of mycobacteria. Gene 190:37–44
Kelly DP (1989) Physiology and biochemistry of unicellular sulfur bacteria. In: Schlegel HG, Bowien B (eds) Autotrophic Bacteria. Springer, Berlin Science Tech Publishers, Madison, pp 193–217
Lahiri C, Mandal S, Ghosh W, Dam B, Roy P (2006) A novel gene cluster soxSRT is essential for the chemolithotrophic oxidation of thiosulfate and tetrathionate by Pseudaminobacter salicylatoxidans KCT001. Curr Microbiol 54:267–273
Mandal S, Chatterjee S, Dam B, Roy P, Das Gupta SK (2007) The dimeric repressor SoxR binds cooperatively to the promoter(s) regulating expression of the sulfur oxidation (sox) operon of Pseudaminobacter salicylatoxidans KCT001. Microbiology 153:80–91
Miller JH (1972) Experiments in molecular genetics. Cold Spring Harbor Laboratory, Cold Spring Harbor, pp 352–355, 403, 404
Mukhopadhyaya PN, Deb C, Lahiri C, Roy P (2000) A soxA gene, encoding a diheme cytochrome c, and a sox locus, essential for sulfur oxidation in a new sulfur lithotrophic bacterium. J Bacteriol 182:4278–4287
Orawski G, Bardischewsky F, Quentmeier A, Rother D, Friedrich CG (2007) The periplasmic thioredoxin SoxS plays a key role in activation in vivo of chemotrophic sulfur oxidation of Paracoccus pantotrophus. Microbiology 153:1081–1086
Pomposiello PJ, Demple B (2001) Redox-operated genetic switches: the SoxR and OxyR transcription factors. Trends Biotechnol 19:109–114
Rother D, Henrich HJ, Quentmeier A, Bardischewsky F, Friedrich CG (2001) Novel genes of the sox gene cluster, mutagenesis of the flavoprotein SoxF, and evidence for a general sulfur-oxidizing system in Paracoccus pantotrophus GB17. J Bacteriol 183:4499–4508
Rother D, Orawski G, Bardischewsky F, Friedrich CG (2005) SoxRS-mediated regulation of chemolithotrophic sulfur oxidation in Paracoccus pantotrophus. Microbiology 151:1707–1716
Rother D, Ringk J, Friedrich CG (2008) Sulfur oxidation of Paracoccus pantotrophus: the sulfur binding protein SoxYZ is the target of the periplasmic thiol-disulfide oxidoreductase SoxS. Microbiol 154:1980–1988
Sambrook J, Russell DW (2001) Molecular cloning: a laboratory manual, 2nd edn. Cold Spring Harbor Laboratory, Cold Spring Harbor
Acknowledgments
SM is grateful to CSIR for his fellowship. Author is thankful to Dr. Sujoy K Dasgupta and Dr. Wriddhiman Ghosh for their valuable comments and constant support.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mandal, S. The Sulfur Oxidation Operon Repressor Function is Influenced by the Product of its Adjacent Upstream ORF in Pseudaminobacter salicylatoxidans KCT001. Curr Microbiol 64, 259–264 (2012). https://doi.org/10.1007/s00284-011-0063-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00284-011-0063-6