Recombinant Escherichia coli Multidrug transporter emrE (emrE)

1. Optimal positions of the peptide staple were determined using free-energy simulations of peptide binding to monomeric EmrE Three of the four top-scoring peptides selected for experimental testing resulted in significant inhibition of proton-driven ethidium efflux in live cells without nonspecific toxicity. The approach described here is expected to be of general use for the design of peptide therapeutics. PMID: 30082384
2. Not only can EmrE export diverse drug substrates, it can couple antiport of a drug to either one or two protons, performing both electrogenic and electroneutral transport of a single substrate. PMID: 29114048
3. In a practical application of the BLaTM system, the authors find that the antiparallel interaction of TMD4, the known dimerization domain of the dual-topology small multidrug transporter EmrE, is sequence-specific and much stronger than the parallel one. PMID: 28432015
4. This work reveals a mechanism for regulating membrane-protein topogenesis, in which initially misintegrated configurations of the proteins undergo post-translational annealing to reach fully integrated multispanning topologies. PMID: 26408961
5. The results indicate that a binding pattern can be formed in the EmrE in such a way that GLU14 binds to the positively charged fragment of a substrate molecule, and other aromatic residues. PMID: 26014489
6. Based on these structural results, EmrE mutants were created to ascertain whether a specific loop length and composition were necessary for function. PMID: 25406320
7. Replacement of the corresponding alanine residue with serine in two different homologues of EmrE enables them to provide robust resistance to methyl viologen in vivo and to transport methyl viologen as determined in proteoliposome assays. PMID: 25479374
8. this study has analyzed fused versions of the dual-topology transporter EmrE, a member of the small multidrug resistance family, by blue-native PAGE and in vivo activity measurements. PMID: 24690367
9. the rate of interconversion between the inward- and outward-facing states of EmrE varies over 3 orders of magnitude. Thus, the identity of the bound substrate controls the rate of this critical step in the transport process. PMID: 24448799
10. The study identified that betaine and choline are natural quaternary cation compounds substrates of EmrE. PMID: 22942246
11. Transforming EmrE, a drug/H+ antiporter, into a polyamine importer by a single mutation. PMID: 23035252
12. EmrE structure in liposomes and the substrate-induced conformational changes PMID: 20551331
13. topology of inner membrane protein EmrE could be controlled by a single positively charged residue placed in different locations throughout the protein, including C terminus; observation points to plasticity in membrane protein insertion mechanisms PMID: 20508091
14. EmrE is a proton coupled multi-drug transporter of Escherichia coli PMID: 15189838
15. EmrE transports monovalent and divalent substrates with the same stoichiometry PMID: 15371426
16. analysis of ligand binding to the multidrug resistance protein EmrE by isothermal titration calorimetry PMID: 15501941
17. Crystallography of the integral membrane protein EmrE from Escherichia coli PMID: 15583400
18. analysis of a unique carboxyl residue in EmrE using mass spectrometry PMID: 15623511
19. Tryptophan 63, the only essential Trp residue in EmrE, is also a sensor for ligand binding and/or conformational changes following the EmrE substrate binding reaction. PMID: 15882076
20. analysis of the binding domain of EmrE PMID: 16049002
21. topological analysis of EmrE protein PMID: 17003034
22. 3-D structure of EmrE acquired by electron cryo-microscopy (cryo-EM) at 7.5 Angstroms resolution in the membrane plane showed that parts of the structure are related by quasi-symmetry PMID: 17005200
23. it was experimentally demonstrated that the evolution of the membrane protein, EmrE, composed of two homologous but oppositely oriented domains can occur in a small number of steps PMID: 17255477
24. The 3D structures of EmrE have since been retracted because of faulty software, but the suggestion that the protomers in the dimer are in an antiparallel topological orientation sparked controversy that is still ongoing. PMID: 17452106
25. Data compare the NMR spectra obtained from wildtype EmrE to those obtained from the mutant EmrE-E14C and the experiments allow to assign the chemical shift of the carboxylic carbon of E14. PMID: 17976529
26. study reports the corrected structures as recalculated from the original diffraction, new data from selenomethionine (SeMet)-labeled crystals, and functional assays of the recombinant proteins used for structure determination PMID: 18024586
27. Glu14 is a key residue for substrate transport in the EmrE dimer; it is asymmetric PMID: 18042544
28. Constraining the relative topology of homodimeric EmrE protomers within the dimer in order to assay EmrE activity in vivo leads to results that support a parallel topology of EmrE protomers in the functional dimer. PMID: 18059473
29. Data propose a coupled insertion and assembly model for EmrE in which the favorable energetics of the parallel dimer interface override topological constraints arising from weak asymmetry in positive charge distribution. PMID: 18616286
30. The revised X-ray structure with substrate bound suggests that the proposed antiparallel orientation of the monomers is indeed correct; this represents a new structural paradigm in membrane-protein structures. PMID: 19171974
31. Results add further weight to the hypothesis that an increased lateral phospholipid chain pressure hinders EmrE insertion across the bilayer. PMID: 19699749

Show More

Hide All

KEGG: ecj:JW0531

STRING: 316385.ECDH10B_0499