5UHQ
Structure of a SemiSWEET Q20A mutant
Summary for 5UHQ
| Entry DOI | 10.2210/pdb5uhq/pdb |
| Related | 5UHS |
| Descriptor | Sugar transporter SemiSWEET (1 entity in total) |
| Functional Keywords | membrane, transporter, semisweet, transport protein |
| Biological source | Leptospira biflexa serovar Patoc (strain Patoc 1 / ATCC 23582 / Paris) |
| Total number of polymer chains | 4 |
| Total formula weight | 42670.80 |
| Authors | Fastman, N.M.,Feng, L. (deposition date: 2017-01-11, release date: 2017-08-02, Last modification date: 2023-10-04) |
| Primary citation | Latorraca, N.R.,Fastman, N.M.,Venkatakrishnan, A.J.,Frommer, W.B.,Dror, R.O.,Feng, L. Mechanism of Substrate Translocation in an Alternating Access Transporter. Cell, 169:96-107.e12, 2017 Cited by PubMed Abstract: Transporters shuttle molecules across cell membranes by alternating among distinct conformational states. Fundamental questions remain about how transporters transition between states and how such structural rearrangements regulate substrate translocation. Here, we capture the translocation process by crystallography and unguided molecular dynamics simulations, providing an atomic-level description of alternating access transport. Simulations of a SWEET-family transporter initiated from an outward-open, glucose-bound structure reported here spontaneously adopt occluded and inward-open conformations. Strikingly, these conformations match crystal structures, including our inward-open structure. Mutagenesis experiments further validate simulation predictions. Our results reveal that state transitions are driven by favorable interactions formed upon closure of extracellular and intracellular "gates" and by an unfavorable transmembrane helix configuration when both gates are closed. This mechanism leads to tight allosteric coupling between gates, preventing them from opening simultaneously. Interestingly, the substrate appears to take a "free ride" across the membrane without causing major structural rearrangements in the transporter. PubMed: 28340354DOI: 10.1016/j.cell.2017.03.010 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.78 Å) |
Structure validation
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