2X79

Inward facing conformation of Mhp1

Summary for 2X79

• Entry DOI: 10.2210/pdb2x79/pdb
• Descriptor: Hydantoin permease (1 entity in total)
• Functional Keywords: transport protein, transporter, membrane protein
• Biological source: Microbacterium liquefaciens
• Total number of polymer chains: 1
• Total formula weight: 55556.68

Authors

Shimamura, T.,Weyand, S.,Beckstein, O.,Rutherford, N.G.,Hadden, J.M.,Sharples, D.,Sansom, M.S.P.,Iwata, S.,Henderson, P.J.F.,Cameron, A.D. (deposition date: 2010-02-25, release date: 2010-05-05, Last modification date: 2024-10-23)

Primary citation

Shimamura, T.,Weyand, S.,Beckstein, O.,Rutherford, N.G.,Hadden, J.M.,Sharples, D.,Sansom, M.S.P.,Iwata, S.,Henderson, P.J.F.,Cameron, A.D.
Molecular Basis of Alternating Access Membrane Transport by the Sodium-Hydantoin Transporter Mhp1.
Science, 328:470-, 2010

PubMed Abstract: The structure of the sodium-benzylhydantoin transport protein Mhp1 from Microbacterium liquefaciens comprises a five-helix inverted repeat, which is widespread among secondary transporters. Here, we report the crystal structure of an inward-facing conformation of Mhp1 at 3.8 angstroms resolution, complementing its previously described structures in outward-facing and occluded states. From analyses of the three structures and molecular dynamics simulations, we propose a mechanism for the transport cycle in Mhp1. Switching from the outward- to the inward-facing state, to effect the inward release of sodium and benzylhydantoin, is primarily achieved by a rigid body movement of transmembrane helices 3, 4, 8, and 9 relative to the rest of the protein. This forms the basis of an alternating access mechanism applicable to many transporters of this emerging superfamily.

PubMed: 20413494
DOI: 10.1126/SCIENCE.1186303

Experimental method

X-RAY DIFFRACTION (3.8 Å)