{"doi":"10.1101/2025.07.31.667927","title":"Selectivity of the time-dependent <i>M. tuberculosis</i> LeuRS inhibitor ganfeborole is driven by target vulnerability","abstract":"ABSTRACT Ganfeborole (GSK3036656) inhibits the Mycobacterium tuberculosis leucyl-tRNA-synthetase (mtLeuRS) and is in phase 2a clinical trials for the treatment of tuberculosis. Here we show that ganfeborole is a time-dependent inhibitor of mtLeuRS (IC 50 1 nM) and generates a post-antibiotic effect of 77 h at 50xMIC (MIC 0.058 μM) with M. tuberculosis H37Rv ( Mtb ), indicating that mtLeuRS is a highly vulnerable drug target and supporting the excellent in vivo efficacy of the drug. Ganfeborole is also a potent time-dependent inhibitor of Escherichia coli LeuRS (ecLeuRS, IC 50 2 nM), however no antibacterial activity is observed towards E. coli up to 1 mM ganfeborole despite the observation that less potent ganfeborole analogs have antibacterial activity. To rationalize this observation, we propose that ganfeborole forms a complex with AMP that binds to the ecLeuRS editing site but does not impact aminoacylation. In support, addition of 12.5 μM norvaline generates a ganfeborole MIC of 0.4 μM since ecLeuRS is unable to hydrolyze norvaline-tRNA Leu . Additionally, mutations that reduce the affinity and residence time of ganfeborole-AMP on ecLeuRS result in antibacterial activity. We propose that the activity of ganfeborole towards Mtb is because mtLeuRS is a highly vulnerable target so that only low levels of enzyme need to be inhibited by the ganfeborole-tRNA Leu complex in contrast to ecLeuRS, which we previously demonstrated is a low vulnerability target.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2025,"id":571562,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9607,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":928015,"name":"YongLe He","orcid":"0000-0001-7274-535X","position":1,"is_corresponding":false},{"id":1385578,"name":"Siobhan A. Cohen","orcid":null,"position":2,"is_corresponding":false},{"id":1385115,"name":"Amanda R. Strohm","orcid":"0009-0003-2334-9504","position":3,"is_corresponding":false},{"id":352850,"name":"Gauri Shetye","orcid":"0000-0001-6282-2833","position":4,"is_corresponding":false},{"id":352862,"name":"Scott G. Franzblau","orcid":"0000-0002-8698-0243","position":5,"is_corresponding":false},{"id":740842,"name":"Stephen G. Walker","orcid":"0009-0006-3560-4738","position":6,"is_corresponding":false},{"id":1477677,"name":"Dickon Alley","orcid":null,"position":7,"is_corresponding":false},{"id":22118,"name":"Peter J. Tonge","orcid":"0000-0003-1606-3471","position":8,"is_corresponding":false},{"id":1290458,"name":"Mingqian Wang","orcid":"0000-0002-1341-6051","position":0,"is_corresponding":true}],"reference_count":32,"raw_metadata":null,"created_at":"2026-07-19T02:57:15.755535Z","pmid":null,"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":[]}