ID EMRE_ECOLI Reviewed; 110 AA. AC P23895; Q2MBN8; DT 01-NOV-1991, integrated into UniProtKB/Swiss-Prot. DT 01-NOV-1991, sequence version 1. DT 27-MAR-2024, entry version 179. DE RecName: Full=Multidrug transporter EmrE; DE AltName: Full=Efflux-multidrug resistance protein EmrE; DE AltName: Full=Ethidium resistance protein; DE AltName: Full=Methyl viologen resistance protein C; GN Name=emrE; Synonyms=eb, mvrC; OrderedLocusNames=b0543, JW0531; OS Escherichia coli (strain K12). OC Bacteria; Pseudomonadota; Gammaproteobacteria; Enterobacterales; OC Enterobacteriaceae; Escherichia. OX NCBI_TaxID=83333; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RX PubMed=1936950; DOI=10.1016/0378-1097(91)90338-b; RA Purewal A.S.; RT "Nucleotide sequence of the ethidium efflux gene from Escherichia coli."; RL FEMS Microbiol. Lett. 66:229-231(1991). RN [2] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RX PubMed=1320256; DOI=10.1093/nar/20.12.3159; RA Morimyo M., Hongo E., Hama-Inaba H., Machida I.; RT "Cloning and characterization of the mvrC gene of Escherichia coli K-12 RT which confers resistance against methyl viologen toxicity."; RL Nucleic Acids Res. 20:3159-3165(1992). RN [3] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=K12 / MG1655 / ATCC 47076; RA Chung E., Allen E., Araujo R., Aparicio A.M., Davis K., Duncan M., RA Federspiel N., Hyman R., Kalman S., Komp C., Kurdi O., Lew H., Lin D., RA Namath A., Oefner P., Roberts D., Schramm S., Davis R.W.; RT "Sequence of minutes 4-25 of Escherichia coli."; RL Submitted (JAN-1997) to the EMBL/GenBank/DDBJ databases. RN [4] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=K12 / MG1655 / ATCC 47076; RX PubMed=9278503; DOI=10.1126/science.277.5331.1453; RA Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., RA Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., RA Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., RA Shao Y.; RT "The complete genome sequence of Escherichia coli K-12."; RL Science 277:1453-1462(1997). RN [5] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911; RX PubMed=16738553; DOI=10.1038/msb4100049; RA Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., RA Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.; RT "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 RT and W3110."; RL Mol. Syst. Biol. 2:E1-E5(2006). RN [6] RP FUNCTION, AND KINETIC PARAMETERS. RC STRAIN=K12 / JM109 / ATCC 53323; RX PubMed=7896833; DOI=10.1074/jbc.270.12.6856; RA Yerushalmi H., Lebendiker M., Schuldiner S.; RT "EmrE, an Escherichia coli 12-kDa multidrug transporter, exchanges toxic RT cations and H+ and is soluble in organic solvents."; RL J. Biol. Chem. 270:6856-6863(1995). RN [7] RP FUNCTION, AND REVIEW. RX PubMed=9050242; DOI=10.1242/jeb.200.2.335; RA Schuldiner S., Lebendiker M., Yerushalmi H.; RT "EmrE, the smallest ion-coupled transporter, provides a unique paradigm for RT structure-function studies."; RL J. Exp. Biol. 200:335-341(1997). RN [8] RP FUNCTION, PH DEPENDENCE, AND MUTAGENESIS OF GLU-14. RC STRAIN=K12 / JM109 / ATCC 53323; RX PubMed=10681497; DOI=10.1074/jbc.275.8.5264; RA Yerushalmi H., Schuldiner S.; RT "An essential glutamyl residue in EmrE, a multidrug antiporter from RT Escherichia coli."; RL J. Biol. Chem. 275:5264-5269(2000). RN [9] RP FUNCTION. RX PubMed=11574548; DOI=10.1074/jbc.m108231200; RA Ninio S., Rotem D., Schuldiner S.; RT "Functional analysis of novel multidrug transporters from human RT pathogens."; RL J. Biol. Chem. 276:48250-48256(2001). RN [10] RP REVIEW. RX PubMed=11443233; DOI=10.1152/physiologyonline.2001.16.3.130; RA Schuldiner S., Granot D., Mordoch S.S., Ninio S., Rotem D., Soskin M., RA Tate C.G., Yerushalmi H.; RT "Small is mighty: EmrE, a multidrug transporter as an experimental RT paradigm."; RL News Physiol. Sci. 16:130-134(2001). RN [11] RP MUTAGENESIS OF LEU-7; ALA-10; ILE-11; GLU-14; GLY-17 AND THR-18. RX PubMed=12590142; DOI=10.1074/jbc.m213120200; RA Gutman N., Steiner-Mordoch S., Schuldiner S.; RT "An amino acid cluster around the essential Glu-14 is part of the RT substrate- and proton-binding domain of EmrE, a multidrug transporter from RT Escherichia coli."; RL J. Biol. Chem. 278:16082-16087(2003). RN [12] RP SUBCELLULAR LOCATION, AND TOPOLOGY. RX PubMed=15044024; DOI=10.1016/s0014-5793(04)00240-6; RA Ninio S., Elbaz Y., Schuldiner S.; RT "The membrane topology of EmrE - a small multidrug transporter from RT Escherichia coli."; RL FEBS Lett. 562:193-196(2004). RN [13] RP SUBUNIT. RX PubMed=15111102; DOI=10.1016/s0014-5793(04)00228-5; RA Ubarretxena-Belandia I., Tate C.G.; RT "New insights into the structure and oligomeric state of the bacterial RT multidrug transporter EmrE: an unusual asymmetric homo-dimer."; RL FEBS Lett. 564:234-238(2004). RN [14] RP FUNCTION. RX PubMed=15371426; DOI=10.1074/jbc.m408187200; RA Rotem D., Schuldiner S.; RT "EmrE, a multidrug transporter from Escherichia coli, transports monovalent RT and divalent substrates with the same stoichiometry."; RL J. Biol. Chem. 279:48787-48793(2004). RN [15] RP SUBUNIT. RX PubMed=14755055; DOI=10.1073/pnas.0306533101; RA Elbaz Y., Steiner-Mordoch S., Danieli T., Schuldiner S.; RT "In vitro synthesis of fully functional EmrE, a multidrug transporter, and RT study of its oligomeric state."; RL Proc. Natl. Acad. Sci. U.S.A. 101:1519-1524(2004). RN [16] RP MUTAGENESIS OF TRP-63, AND SUBUNIT. RX PubMed=15882076; DOI=10.1021/bi050356t; RA Elbaz Y., Tayer N., Steinfels E., Steiner-Mordoch S., Schuldiner S.; RT "Substrate-induced tryptophan fluorescence changes in EmrE, the smallest RT ion-coupled multidrug transporter."; RL Biochemistry 44:7369-7377(2005). RN [17] RP SUBSTRATE-BINDING CAVITY. RX PubMed=16049002; DOI=10.1074/jbc.m504910200; RA Sharoni M., Steiner-Mordoch S., Schuldiner S.; RT "Exploring the binding domain of EmrE, the smallest multidrug RT transporter."; RL J. Biol. Chem. 280:32849-32855(2005). RN [18] RP TOPOLOGY [LARGE SCALE ANALYSIS]. RC STRAIN=K12 / MG1655 / ATCC 47076; RX PubMed=15919996; DOI=10.1126/science.1109730; RA Daley D.O., Rapp M., Granseth E., Melen K., Drew D., von Heijne G.; RT "Global topology analysis of the Escherichia coli inner membrane RT proteome."; RL Science 308:1321-1323(2005). RN [19] RP MUTAGENESIS OF TYR-4; TYR-6; TYR-40; TYR-53 AND TYR-60. RX PubMed=16672221; DOI=10.1074/jbc.m602088200; RA Rotem D., Steiner-Mordoch S., Schuldiner S.; RT "Identification of tyrosine residues critical for the function of an ion- RT coupled multidrug transporter."; RL J. Biol. Chem. 281:18715-18722(2006). RN [20] RP SUBUNIT. RX PubMed=17003034; DOI=10.1074/jbc.m607186200; RA Soskine M., Mark S., Tayer N., Mizrachi R., Schuldiner S.; RT "On parallel and antiparallel topology of a homodimeric multidrug RT transporter."; RL J. Biol. Chem. 281:36205-36212(2006). RN [21] RP TOPOLOGY OF MUTANT. RX PubMed=20308069; DOI=10.1074/jbc.m110.108746; RA Nasie I., Steiner-Mordoch S., Gold A., Schuldiner S.; RT "Topologically random insertion of EmrE supports a pathway for evolution of RT inverted repeats in ion-coupled transporters."; RL J. Biol. Chem. 285:15234-15244(2010). RN [22] RP SUBUNIT, SUBCELLULAR LOCATION, AND DOMAIN. RX PubMed=20551331; DOI=10.1074/jbc.m110.132621; RA Amadi S.T., Koteiche H.A., Mishra S., McHaourab H.S.; RT "Structure, dynamics, and substrate-induced conformational changes of the RT multidrug transporter EmrE in liposomes."; RL J. Biol. Chem. 285:26710-26718(2010). RN [23] RP SUBCELLULAR LOCATION. RX PubMed=20508091; DOI=10.1126/science.1188950; RA Seppaelae S., Slusky J.S., Lloris-Garcera P., Rapp M., von Heijne G.; RT "Control of membrane protein topology by a single C-terminal residue."; RL Science 328:1698-1700(2010). RN [24] RP SUBUNIT, SUBCELLULAR LOCATION, AND DOMAIN. RX PubMed=22178925; DOI=10.1038/nature10703; RA Morrison E.A., DeKoster G.T., Dutta S., Vafabakhsh R., Clarkson M.W., RA Bahl A., Kern D., Ha T., Henzler-Wildman K.A.; RT "Antiparallel EmrE exports drugs by exchanging between asymmetric RT structures."; RL Nature 481:45-50(2011). RN [25] RP REVIEW. RX PubMed=22100111; DOI=10.1016/j.sbi.2011.10.004; RA Henzler-Wildman K.; RT "Analyzing conformational changes in the transport cycle of EmrE."; RL Curr. Opin. Struct. Biol. 22:38-43(2012). RN [26] RP FUNCTION. RX PubMed=22942246; DOI=10.1128/jb.00666-12; RA Bay D.C., Turner R.J.; RT "Small multidrug resistance protein EmrE reduces host pH and osmotic RT tolerance to metabolic quaternary cation osmoprotectants."; RL J. Bacteriol. 194:5941-5948(2012). RN [27] RP FUNCTION. RX PubMed=23042996; DOI=10.1128/jb.01318-12; RA Nasie I., Steiner-Mordoch S., Schuldiner S.; RT "New substrates on the block: clinically relevant resistances for EmrE and RT homologues."; RL J. Bacteriol. 194:6766-6770(2012). RN [28] RP SUBUNIT, SUBCELLULAR LOCATION, AND MUTAGENESIS OF GLY-67. RX PubMed=23920359; DOI=10.1016/j.jmb.2013.07.039; RA Lloris-Garcera P., Slusky J.S., Seppaelae S., Priess M., Schaefer L.V., RA von Heijne G.; RT "In vivo trp scanning of the small multidrug resistance protein EmrE RT confirms 3D structure models'."; RL J. Mol. Biol. 425:4642-4651(2013). RN [29] RP FUNCTION, ACTIVITY REGULATION, AND DOMAIN. RX PubMed=24448799; DOI=10.1074/jbc.m113.535328; RA Morrison E.A., Henzler-Wildman K.A.; RT "Transported substrate determines exchange rate in the multidrug resistance RT transporter EmrE."; RL J. Biol. Chem. 289:6825-6836(2014). RN [30] RP FUNCTION. RX PubMed=29114048; DOI=10.1073/pnas.1708671114; RA Robinson A.E., Thomas N.E., Morrison E.A., Balthazor B.M., RA Henzler-Wildman K.A.; RT "New free-exchange model of EmrE transport."; RL Proc. Natl. Acad. Sci. U.S.A. 114:E10083-E10091(2017). RN [31] RP FUNCTION, AND DOMAIN. RX PubMed=30287687; DOI=10.1074/jbc.ra118.005430; RA Thomas N.E., Wu C., Morrison E.A., Robinson A.E., Werner J.P., RA Henzler-Wildman K.A.; RT "The C terminus of the bacterial multidrug transporter EmrE couples drug RT binding to proton release."; RL J. Biol. Chem. 293:19137-19147(2018). RN [32] RP STRUCTURE BY NMR, AND SUBCELLULAR LOCATION. RX PubMed=9688273; DOI=10.1046/j.1432-1327.1998.2540610.x; RA Schwaiger M., Lebendiker M., Yerushalmi H., Coles M., Groeger A., RA Schwarz C., Schuldiner S., Kessler H.; RT "NMR investigation of the multidrug transporter EmrE, an integral membrane RT protein."; RL Eur. J. Biochem. 254:610-619(1998). RN [33] RP STRUCTURE BY ELECTRON MICROSCOPY (7.5 ANGSTROMS) IN COMPLEX WITH THE DRUG RP TPP(+), AND SUBUNIT. RX PubMed=14633977; DOI=10.1093/emboj/cdg611; RA Ubarretxena-Belandia I., Baldwin J.M., Schuldiner S., Tate C.G.; RT "Three-dimensional structure of the bacterial multidrug transporter EmrE RT shows it is an asymmetric homodimer."; RL EMBO J. 22:6175-6181(2003). RN [34] RP X-RAY CRYSTALLOGRAPHY (3.8 ANGSTROMS), AND RETRACTED PAPER. RX PubMed=14970332; DOI=10.1073/pnas.0400137101; RA Ma C., Chang G.; RT "Structure of the multidrug resistance efflux transporter EmrE from RT Escherichia coli."; RL Proc. Natl. Acad. Sci. U.S.A. 101:2852-2857(2004). RN [35] RP ERRATUM OF PUBMED:14970332, AND RETRACTION NOTICE OF PUBMED:14970332. RX PubMed=17360700; DOI=10.1073/pnas.0700711104; RA Ma C., Chang G.; RL Proc. Natl. Acad. Sci. U.S.A. 104:3668-3668(2007). RN [36] RP X-RAY CRYSTALLOGRAPHY (3.7 ANGSTROMS) IN COMPLEX WITH THE DRUG TPP(+), AND RP RETRACTED PAPER. RX PubMed=16373573; DOI=10.1126/science.1119776; RA Pornillos O., Chen Y.-J., Chen A.P., Chang G.; RT "X-ray structure of the EmrE multidrug transporter in complex with a RT substrate."; RL Science 310:1950-1953(2005). RN [37] RP ERRATUM OF PUBMED:16373573, AND RETRACTION NOTICE OF PUBMED:16373573. RX PubMed=17185584; DOI=10.1126/science.314.5807.1875b; RA Chang G., Roth C.B., Reyes C.L., Pornillos O., Chen Y.J., Chen A.P.; RL Science 314:1875-1875(2006). RN [38] {ECO:0007744|PDB:2I68} RP STRUCTURE BY ELECTRON MICROSCOPY (7.5 ANGSTROMS), 3D-STRUCTURE MODELING, RP SUBUNIT, AND SUBCELLULAR LOCATION. RX PubMed=17005200; DOI=10.1016/j.jmb.2006.08.072; RA Fleishman S.J., Harrington S.E., Enosh A., Halperin D., Tate C.G., RA Ben-Tal N.; RT "Quasi-symmetry in the cryo-EM structure of EmrE provides the key to RT modeling its transmembrane domain."; RL J. Mol. Biol. 364:54-67(2006). RN [39] {ECO:0007744|PDB:3B5D, ECO:0007744|PDB:3B61, ECO:0007744|PDB:3B62} RP X-RAY CRYSTALLOGRAPHY (3.80 ANGSTROMS) OF APOPROTEIN AND IN COMPLEXES WITH RP TPP, FUNCTION, SUBUNIT, AND SUBCELLULAR LOCATION. RX PubMed=18024586; DOI=10.1073/pnas.0709387104; RA Chen Y.J., Pornillos O., Lieu S., Ma C., Chen A.P., Chang G.; RT "X-ray structure of EmrE supports dual topology model."; RL Proc. Natl. Acad. Sci. U.S.A. 104:18999-19004(2007). RN [40] RP STRUCTURE BY ELECTRON MICROSCOPY, AND DOMAIN. RX PubMed=18295794; DOI=10.1016/j.jmb.2008.01.056; RA Korkhov V.M., Tate C.G.; RT "Electron crystallography reveals plasticity within the drug binding site RT of the small multidrug transporter EmrE."; RL J. Mol. Biol. 377:1094-1103(2008). CC -!- FUNCTION: Multidrug efflux protein that confers resistance to a wide CC range of toxic compounds, including ethidium, methyl viologen, CC acriflavine, tetraphenylphosphonium (TPP(+)), benzalkonium, propidium, CC dequalinium and the aminoglycoside antibiotics streptomycin and CC tobramycin (PubMed:7896833, PubMed:9050242, PubMed:10681497, CC PubMed:11574548, PubMed:15371426, PubMed:18024586, PubMed:18295794, CC PubMed:23042996, PubMed:24448799). Can also transport the CC osmoprotectants betaine and choline (PubMed:22942246). The drug efflux CC is coupled to an influx of protons (PubMed:7896833, PubMed:15371426, CC PubMed:29114048). Can couple antiport of a drug to either one or two CC protons, performing both electrogenic and electroneutral transport of a CC single substrate (PubMed:29114048). Simultaneously binds and CC cotransports proton and drug (PubMed:29114048, PubMed:30287687). CC {ECO:0000269|PubMed:10681497, ECO:0000269|PubMed:11574548, CC ECO:0000269|PubMed:15371426, ECO:0000269|PubMed:18024586, CC ECO:0000269|PubMed:18295794, ECO:0000269|PubMed:22942246, CC ECO:0000269|PubMed:23042996, ECO:0000269|PubMed:24448799, CC ECO:0000269|PubMed:29114048, ECO:0000269|PubMed:30287687, CC ECO:0000269|PubMed:7896833, ECO:0000269|PubMed:9050242}. CC -!- ACTIVITY REGULATION: Substrate identity influences both the ground- CC state and transition-state energies for the conformational exchange CC process, emphasizing the coupling between substrate binding and CC transport. {ECO:0000269|PubMed:24448799}. CC -!- BIOPHYSICOCHEMICAL PROPERTIES: CC Kinetic parameters: CC KM=247 uM for methyl viologen {ECO:0000269|PubMed:7896833}; CC Vmax=1572 nmol/min/mg enzyme with methyl viologen as substrate CC {ECO:0000269|PubMed:7896833}; CC pH dependence: CC Optimum pH is 8-8.5. Transport activity occurs from pH 7.5 to 9. CC {ECO:0000269|PubMed:10681497}; CC -!- SUBUNIT: Homodimer (PubMed:14633977, PubMed:15111102, PubMed:14755055, CC PubMed:15882076, PubMed:17003034, PubMed:18024586, PubMed:20551331, CC PubMed:22178925, PubMed:23920359). Forms an antiparallel dimeric CC structure (PubMed:17005200, PubMed:18024586, PubMed:20551331, CC PubMed:22178925, PubMed:23920359). Also forms dimers of homodimers CC (PubMed:14755055). {ECO:0000269|PubMed:14633977, CC ECO:0000269|PubMed:14755055, ECO:0000269|PubMed:15111102, CC ECO:0000269|PubMed:15882076, ECO:0000269|PubMed:17003034, CC ECO:0000269|PubMed:17005200, ECO:0000269|PubMed:18024586, CC ECO:0000269|PubMed:20551331, ECO:0000269|PubMed:22178925, CC ECO:0000269|PubMed:23920359}. CC -!- INTERACTION: CC P23895; P23895: emrE; NbExp=2; IntAct=EBI-8789431, EBI-8789431; CC -!- SUBCELLULAR LOCATION: Cell inner membrane {ECO:0000269|PubMed:15044024, CC ECO:0000269|PubMed:9688273}; Multi-pass membrane protein CC {ECO:0000269|PubMed:15044024, ECO:0000269|PubMed:17005200, CC ECO:0000269|PubMed:9688273}. Note=Forms antiparallel homodimers CC (PubMed:17005200, PubMed:18024586, PubMed:20508091, PubMed:20551331, CC PubMed:22178925, PubMed:23920359). The topology could be controlled by CC a single positively charged residue placed in different locations CC throughout the protein, including the very C terminus CC (PubMed:20508091). {ECO:0000269|PubMed:17005200, CC ECO:0000269|PubMed:18024586, ECO:0000269|PubMed:20508091, CC ECO:0000269|PubMed:20551331, ECO:0000269|PubMed:22178925, CC ECO:0000269|PubMed:23920359}. CC -!- DOMAIN: Binds different substrates in the same active site CC (PubMed:18295794, PubMed:22178925). Binding of the substrate induces CC conformational changes of EmrE (PubMed:18295794, PubMed:20551331, CC PubMed:22178925). The asymmetric antiparallel homodimer exchanges CC between inward- and outward-facing states that are identical except CC that they have opposite orientation in the membrane (PubMed:22178925, CC PubMed:24448799). The conserved C-terminal tail is strongly coupled to CC EmrE's drug-binding domain and participates in secondary gating of CC EmrE-mediated proton/drug transport, occluding the binding pocket of CC fully protonated EmrE in the absence of drug to prevent dissipative CC proton transport (PubMed:30287687). {ECO:0000269|PubMed:18295794, CC ECO:0000269|PubMed:20551331, ECO:0000269|PubMed:22178925, CC ECO:0000269|PubMed:24448799, ECO:0000269|PubMed:30287687}. CC -!- MISCELLANEOUS: Mutants designed to insert with biased topology are CC functional regardless of the topology. {ECO:0000269|PubMed:20308069}. CC -!- MISCELLANEOUS: Encoded by the cryptic lambdoid prophage DLP12. CC -!- SIMILARITY: Belongs to the drug/metabolite transporter (DMT) CC superfamily. Small multidrug resistance (SMR) (TC 2.A.7.1) family. CC {ECO:0000305}. CC -!- CAUTION: The membrane insertion topology of the two monomers was CC controversial and some studies originally suggested a parallel CC arrangement of the two monomers in the EmrE dimer. The antiparallel CC dimeric structure is now the generally accepted functional topology. CC {ECO:0000305, ECO:0000305|PubMed:15044024, CC ECO:0000305|PubMed:17003034}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; Z11877; CAA77936.1; -; Genomic_DNA. DR EMBL; M62732; AAA24190.1; -; Genomic_DNA. DR EMBL; U82598; AAB40740.1; -; Genomic_DNA. DR EMBL; U00096; AAC73644.1; -; Genomic_DNA. DR EMBL; AP009048; BAE76318.1; -; Genomic_DNA. DR PIR; JN0329; JN0329. DR RefSeq; NP_415075.1; NC_000913.3. DR RefSeq; WP_001070439.1; NZ_LN832404.1. DR PDB; 2I68; EM; -; A/B=1-110. DR PDB; 3B5D; X-ray; 3.80 A; A/B=1-110. DR PDB; 3B61; X-ray; 4.50 A; A/B/C/D/E/F/G/H=1-110. DR PDB; 3B62; X-ray; 4.40 A; A/B/C/D=1-110. DR PDB; 7JK8; NMR; -; A/B=1-110. DR PDB; 7MGX; X-ray; 3.13 A; A/B/E/F=1-110. DR PDB; 7MH6; X-ray; 2.85 A; A/B=1-110. DR PDB; 7SFQ; NMR; -; A/B=1-110. DR PDB; 7SSU; X-ray; 3.22 A; A/B=1-110. DR PDB; 7SV9; X-ray; 3.36 A; A/B=1-110. DR PDB; 7SVX; X-ray; 3.90 A; A/B=1-110. DR PDB; 7T00; X-ray; 3.91 A; A/B=1-110. DR PDBsum; 2I68; -. DR PDBsum; 3B5D; -. DR PDBsum; 3B61; -. DR PDBsum; 3B62; -. DR PDBsum; 7JK8; -. DR PDBsum; 7MGX; -. DR PDBsum; 7MH6; -. DR PDBsum; 7SFQ; -. DR PDBsum; 7SSU; -. DR PDBsum; 7SV9; -. DR PDBsum; 7SVX; -. DR PDBsum; 7T00; -. DR AlphaFoldDB; P23895; -. DR BMRB; P23895; -. DR EMDB; EMD-1087; -. DR SMR; P23895; -. DR BioGRID; 4259366; 101. DR ComplexPortal; CPX-2121; EmrE multidrug transporter complex. DR DIP; DIP-9505N; -. DR STRING; 511145.b0543; -. DR TCDB; 2.A.7.1.3; the drug/metabolite transporter (dmt) superfamily. DR PaxDb; 511145-b0543; -. DR DNASU; 948442; -. DR EnsemblBacteria; AAC73644; AAC73644; b0543. DR GeneID; 948442; -. DR KEGG; ecj:JW0531; -. DR KEGG; eco:b0543; -. DR PATRIC; fig|1411691.4.peg.1735; -. DR EchoBASE; EB0623; -. DR eggNOG; COG2076; Bacteria. DR HOGENOM; CLU_133067_0_2_6; -. DR InParanoid; P23895; -. DR OMA; TYALWSG; -. DR OrthoDB; 9808638at2; -. DR PhylomeDB; P23895; -. DR BioCyc; EcoCyc:EMRE-MONOMER; -. DR BioCyc; MetaCyc:EMRE-MONOMER; -. DR SABIO-RK; P23895; -. DR EvolutionaryTrace; P23895; -. DR PRO; PR:P23895; -. DR Proteomes; UP000000318; Chromosome. DR Proteomes; UP000000625; Chromosome. DR GO; GO:1990207; C:EmrE multidrug transporter complex; IPI:ComplexPortal. DR GO; GO:0016020; C:membrane; IDA:EcoliWiki. DR GO; GO:0005886; C:plasma membrane; IDA:EcoCyc. DR GO; GO:0015199; F:amino-acid betaine transmembrane transporter activity; IMP:EcoCyc. DR GO; GO:0015297; F:antiporter activity; IDA:EcoliWiki. DR GO; GO:0015220; F:choline transmembrane transporter activity; IMP:EcoCyc. DR GO; GO:0042802; F:identical protein binding; IPI:IntAct. DR GO; GO:0022857; F:transmembrane transporter activity; IDA:CACAO. DR GO; GO:0042910; F:xenobiotic transmembrane transporter activity; IDA:EcoCyc. DR GO; GO:0071466; P:cellular response to xenobiotic stimulus; IDA:ComplexPortal. DR GO; GO:0015871; P:choline transport; IMP:EcoCyc. DR GO; GO:0006974; P:DNA damage response; IEP:EcoliWiki. DR GO; GO:0031460; P:glycine betaine transport; IMP:EcoCyc. DR GO; GO:0006970; P:response to osmotic stress; IMP:EcoCyc. DR GO; GO:0009410; P:response to xenobiotic stimulus; IMP:EcoliWiki. DR GO; GO:0055085; P:transmembrane transport; IBA:GO_Central. DR GO; GO:1990961; P:xenobiotic detoxification by transmembrane export across the plasma membrane; IDA:ComplexPortal. DR GO; GO:0006805; P:xenobiotic metabolic process; IMP:EcoliWiki. DR GO; GO:0042908; P:xenobiotic transport; IDA:EcoCyc. DR Gene3D; 1.10.3730.20; -; 1. DR InterPro; IPR000390; Small_drug/metabolite_transptr. DR InterPro; IPR045324; Small_multidrug_res. DR PANTHER; PTHR30561:SF1; MULTIDRUG TRANSPORTER EMRE; 1. DR PANTHER; PTHR30561; SMR FAMILY PROTON-DEPENDENT DRUG EFFLUX TRANSPORTER SUGE; 1. DR Pfam; PF00893; Multi_Drug_Res; 1. DR SUPFAM; SSF103481; Multidrug resistance efflux transporter EmrE; 1. PE 1: Evidence at protein level; KW 3D-structure; Antiport; Cell inner membrane; Cell membrane; Membrane; KW Reference proteome; Transmembrane; Transmembrane helix; Transport. FT CHAIN 1..110 FT /note="Multidrug transporter EmrE" FT /id="PRO_0000108074" FT TRANSMEM 4..21 FT /note="Helical; Name=1" FT /evidence="ECO:0000305|PubMed:17005200" FT TRANSMEM 34..52 FT /note="Helical; Name=2" FT /evidence="ECO:0000305|PubMed:17005200" FT TRANSMEM 58..80 FT /note="Helical; Name=3" FT /evidence="ECO:0000305|PubMed:17005200" FT TRANSMEM 87..104 FT /note="Helical; Name=4" FT /evidence="ECO:0000305|PubMed:17005200" FT SITE 4 FT /note="Required for proper coupling between the substrate FT transport and the proton gradient" FT SITE 14 FT /note="Essential for translocation and for substrate and FT proton binding" FT /evidence="ECO:0000305|PubMed:12590142, FT ECO:0000305|PubMed:29114048" FT SITE 40 FT /note="Involved in substrate binding" FT SITE 60 FT /note="Involved in substrate binding" FT SITE 63 FT /note="Involved in substrate binding" FT SITE 110 FT /note="Important for activity" FT /evidence="ECO:0000305|PubMed:30287687" FT MUTAGEN 4 FT /note="Y->C: Still binds substrate. No transport activity FT in the presence of a proton gradient, but still transports FT substrate in the absence of a proton gradient. Resistance FT to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 4 FT /note="Y->F,W: No effect on resistance to toxicants." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 6 FT /note="Y->C,F,L: No effect on resistance to toxicants." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 7 FT /note="L->C: No substrate binding. Resistance to toxicants FT is abolished." FT /evidence="ECO:0000269|PubMed:12590142" FT MUTAGEN 10 FT /note="A->C: Still binds substrate, with lower affinity. FT Resistance to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:12590142" FT MUTAGEN 11 FT /note="I->C: Still binds substrate, with lower affinity. FT Resistance to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:12590142" FT MUTAGEN 14 FT /note="E->C: No substrate binding. No transport activity. FT Resistance to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:10681497, FT ECO:0000269|PubMed:12590142" FT MUTAGEN 14 FT /note="E->D: Still binds substrate. No transport activity FT in the presence of a proton gradient, but still transports FT substrate in the absence of a proton gradient. Resistance FT to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:10681497, FT ECO:0000269|PubMed:12590142" FT MUTAGEN 17 FT /note="G->C: No substrate binding. Resistance to toxicants FT is abolished." FT /evidence="ECO:0000269|PubMed:12590142" FT MUTAGEN 18 FT /note="T->C: Still binds substrate, with lower affinity. FT Resistance to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:12590142" FT MUTAGEN 40 FT /note="Y->C,F,L,M,S,T,V: Modifies substrate specificity." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 53 FT /note="Y->C: No effect on resistance to toxicants." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 60 FT /note="Y->C,F: Still binds substrate, with lower affinity. FT Resistance to toxicants is abolished." FT /evidence="ECO:0000269|PubMed:16672221" FT MUTAGEN 63 FT /note="W->C,Y: No transport activity. Resistance to FT toxicants is abolished." FT /evidence="ECO:0000269|PubMed:15882076" FT MUTAGEN 63 FT /note="W->F: Still binds substrate, with two-fold reduction FT in substrate affinity. Resistance to toxicants is FT abolished." FT /evidence="ECO:0000269|PubMed:15882076" FT MUTAGEN 67 FT /note="G->W: Major destabilizing effect on the dimer form." FT /evidence="ECO:0000269|PubMed:23920359" FT HELIX 3..23 FT /evidence="ECO:0007829|PDB:7MH6" FT STRAND 24..27 FT /evidence="ECO:0007829|PDB:7MH6" FT HELIX 30..50 FT /evidence="ECO:0007829|PDB:7MH6" FT TURN 51..53 FT /evidence="ECO:0007829|PDB:7MH6" FT HELIX 56..78 FT /evidence="ECO:0007829|PDB:7MH6" FT HELIX 88..99 FT /evidence="ECO:0007829|PDB:7MH6" SQ SEQUENCE 110 AA; 11958 MW; 775153FC47D6AE3D CRC64; MNPYIYLGGA ILAEVIGTTL MKFSEGFTRL WPSVGTIICY CASFWLLAQT LAYIPTGIAY AIWSGVGIVL ISLLSWGFFG QRLDLPAIIG MMLICAGVLI INLLSRSTPH //