{"doi":"10.1073/pnas.2110790118","title":"Asymmetric protonation of glutamate residues drives a preferred transport pathway in EmrE","abstract":"Significance EmrE is a proton-coupled efflux pump that confers multidrug resistance to Escherichia coli . Here, we probed the electrostatic environment surrounding each essential Glu14 residue in the EmrE dimer by determining monomer specific p K a values using NMR spectroscopy. We discovered that acid/base chemistry at one of the two Glu14 residues in the homodimer potentiates a global conformational change within EmrE. Our findings revealed that asymmetric protonation states of EmrE leads to a preferred pathway of substrate transport. These insights led to a model to explain how EmrE accomplishes proton-coupled transport without leaking protons. Since the overall structure of EmrE resembles those of other transporters containing inverted repeat domains, our findings have application to other secondary active transporters.","journal":"Proceedings of the National Academy of Sciences","year":2021,"id":177778,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":20,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9506,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":722282,"name":"Ampon Sae Her","orcid":"0000-0001-9594-8678","position":1,"is_corresponding":false},{"id":346897,"name":"Nathaniel J. Traaseth","orcid":"0000-0002-1185-6088","position":2,"is_corresponding":false},{"id":722281,"name":"Jianping Li","orcid":"0000-0002-2334-6456","position":0,"is_corresponding":true}],"reference_count":43,"raw_metadata":null,"created_at":"2026-07-18T23:47:32.096934Z","pmid":"34607959","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}