Structural Basis of Ion-Substrate Coupling in the Sodium-Dependent Dicarboxylate Transporter VcINDY
- Description
VcINDY is a sodium-dependent dicarboxylate transporter that imports tricarboxylic acid cycle intermediates across the inner membrane of Vibrio cholerae. This study used a combination of structure determination by single-particle cryo-electron microscopy, substrate-binding affinity measurements by intrinsic tryptophan fluorescence quenching, and position accessibility quantification by site-directed cysteine alkylation assay to demonstrate that the VcINDY protein couples sodium and substrate binding via a previously unseen cooperative mechanism. This dataset includes particle stacks of VcINDY and structure of VcINDY in sodium-saturating and sodium-free conditions. The findings reveal that VcINDY’s conformational selection mechanism is a result of the sodium-dependent formation of the substrate binding site.
Access
- Restrictions
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Free to All
- Instructions
- The cryo-electron microscopy particle stacks, maps, and models generated in this study have been deposited in the Electron Microscopy Public Image Archive (EMPIAR) database, Electron Microscopy Data Bank (EMDB) database, and Protein Data Bank (PDB).
- Grant Support
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High Performance Computing Core/NYU Langone HealthMathers Foundation/Mathers FoundationTESS Research Foundation/TESS Research Foundation210121/Z/18/Z/Wellcome TrustBB/V007424/1/Biotechnology and Biological Sciences Research Council129844-PF-17-135-01-TBE/American Cancer SocietyW81XWH-16-1-0153/Department of Defense