Antiparallel Dimers of the Small Multidrug Resistance Protein EmrE Are More Stable Than Parallel Dimers

Background: EmrE is a dual-topology membrane protein, but it is not clear whether the active form is composed of parallel or anti-parallel dimers. Results: Antiparallel EmrE dimers are more stable than parallel dimers. Conclusion: Antiparallel EmrE dimers most likely correspond to the functional form of the protein. Significance: The results provide new information on the functional form of EmrE.