Download MendeleySolution Structure of the Guanine Nucleotide-binding STAS Domain of SLC26-related SulP Protein Rv1739c from Mycobacterium tuberculosis.
Sharma, A.K., Ye, L., Baer, C.E., Shanmugasundaram, K., Alber, T., Alper, S.L., Rigby, A.C.(2011) J Biol Chem 286: 8534-8544
- PubMed: 21190940
- DOI: https://doi.org/10.1074/jbc.M110.165449
- Primary Citation of Related Structures:
2KLN - PubMed Abstract:
The structure and intrinsic activities of conserved STAS domains of the ubiquitous SulP/SLC26 anion transporter superfamily have until recently remained unknown. Here we report the heteronuclear, multidimensional NMR spectroscopy solution structure of the STAS domain from the SulP/SLC26 putative anion transporter Rv1739c of Mycobacterium tuberculosis. The 0.87-Å root mean square deviation structure revealed a four-stranded β-sheet with five interspersed α-helices, resembling the anti-σ factor antagonist fold. Rv1739c STAS was shown to be a guanine nucleotide-binding protein, as revealed by nucleotide-dependent quench of intrinsic STAS fluorescence and photoaffinity labeling. NMR chemical shift perturbation analysis partnered with in silico docking calculations identified solvent-exposed STAS residues involved in nucleotide binding. Rv1739c STAS was not an in vitro substrate of mycobacterial kinases or anti-σ factors. These results demonstrate that Rv1739c STAS binds guanine nucleotides at physiological concentrations and undergoes a ligand-induced conformational change but, unlike anti-σ factor antagonists, may not mediate signals via phosphorylation.
Organizational Affiliation:
From the Divison of Molecular and Vascular Medicine,; Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, and; Department of Medicine, Harvard Medical School, Boston, Massachusetts 02215 and.
