This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hall, J. A. Articles by Pajor, A. M. Search for Related Content PubMed PubMed Citation Articles by Hall, J. A. Articles by Pajor, A. M.

 Previous Article  |  Next Article 

Journal of Bacteriology, February 2007, p. 880-885, Vol. 189, No. 3
0021-9193/07/$08.00+0     doi:10.1128/JB.01452-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Functional Reconstitution of SdcS, a Na⁺-Coupled Dicarboxylate Carrier Protein from Staphylococcus aureus

Jason A. Hall^, and Ana M. Pajor^*

Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555

Received 13 September 2006/ Accepted 7 November 2006

In Staphylococcus aureus, the transport of dicarboxylates is mediated in part by the Na⁺-linked carrier protein SdcS. This transporter is a member of the divalent-anion/Na⁺ symporter (DASS) family, a group that includes the mammalian Na⁺/dicarboxylate cotransporters NaDC1 and NaDC3. In earlier work, we cloned and expressed SdcS in Escherichia coli and found it to have transport properties similar to those of its eukaryotic counterparts (J. A. Hall and A. M. Pajor, J. Bacteriol. 187:5189-5194, 2005). Here, we report the partial purification and subsequent reconstitution of functional SdcS into liposomes. These proteoliposomes exhibited succinate counterflow activity, as well as Na⁺ electrochemical-gradient-driven transport. Examination of substrate specificity indicated that the minimal requirement necessary for transport was a four-carbon terminal dicarboxylate backbone and that productive substrate-transporter interaction was sensitive to substitutions at the substrate C-2 and C-3 positions. Further analysis established that SdcS facilitates an electroneutral symport reaction having a 2:1 cation/dicarboxylate ratio. This study represents the first characterization of a reconstituted Na⁺-coupled DASS family member, thus providing an effective method to evaluate functional, as well as structural, aspects of DASS transporters in a system free of the complexities and constraints associated with native membrane environments.

---

* Corresponding author. Mailing address: Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645. Phone: (409) 772-3434. Fax: (409) 772-5102. E-mail: ampajor{at}utmb.edu.

Published ahead of print on 17 November 2006.

Present address: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.

---

Journal of Bacteriology, February 2007, p. 880-885, Vol. 189, No. 3
0021-9193/07/$08.00+0     doi:10.1128/JB.01452-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

This article has been cited by other articles:

• Youn, J.-W., Jolkver, E., Kramer, R., Marin, K., Wendisch, V. F. (2009). Characterization of the Dicarboxylate Transporter DctA in Corynebacterium glutamicum. J. Bacteriol. 191: 5480-5488 [Abstract] [Full Text]  
• Youn, J.-W., Jolkver, E., Kramer, R., Marin, K., Wendisch, V. F. (2008). Identification and Characterization of the Dicarboxylate Uptake System DccT in Corynebacterium glutamicum. J. Bacteriol. 190: 6458-6466 [Abstract] [Full Text]  
• Teramoto, H., Shirai, T., Inui, M., Yukawa, H. (2008). Identification of a Gene Encoding a Transporter Essential for Utilization of C4 Dicarboxylates in Corynebacterium glutamicum. Appl. Environ. Microbiol. 74: 5290-5296 [Abstract] [Full Text]