{"doi":"10.7554/elife.91930","title":"ESAT-6 undergoes self-association at phagosomal pH and an ESAT-6-specific nanobody restricts M. tuberculosis growth in macrophages","abstract":"(Mtb) is known to survive within macrophages by compromising the integrity of the phagosomal compartment in which it resides. This activity primarily relies on the ESX-1 secretion system, predominantly involving the protein duo ESAT-6 and CFP-10. CFP-10 likely acts as a chaperone, while ESAT-6 likely disrupts phagosomal membrane stability via a largely unknown mechanism. we employ a series of biochemical analyses, protein modeling techniques, and a novel ESAT-6-specific nanobody to gain insight into the ESAT-6's mode of action. First, we measure the binding kinetics of the tight 1:1 complex formed by ESAT-6 and CFP-10 at neutral pH. Subsequently, we demonstrate a rapid self-association of ESAT-6 into large complexes under acidic conditions, leading to the identification of a stable tetrameric ESAT-6 species. Using molecular dynamics simulations, we pinpoint the most probable interaction interface. Furthermore, we show that cytoplasmic expression of an anti-ESAT-6 nanobody blocks Mtb replication, thereby underlining the pivotal role of ESAT-6 in intracellular survival. Together, these data suggest that ESAT-6 acts by a pH-dependent mechanism to establish two-way communication between the cytoplasm and the Mtb-containing phagosome.","journal":"eLife","year":2023,"id":329798,"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":18,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9552,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2023-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1052984,"name":"Mila Trank-Greene","orcid":"0009-0000-4934-3811","position":1,"is_corresponding":false},{"id":552210,"name":"Xammy Nguyenla","orcid":"0000-0002-7532-8356","position":2,"is_corresponding":false},{"id":1052985,"name":"Aidan Anastas","orcid":"0009-0005-3875-1162","position":3,"is_corresponding":false},{"id":1052986,"name":"Sintayehu K Gurmessa","orcid":"0000-0003-1644-2359","position":4,"is_corresponding":false},{"id":753658,"name":"Ilaria R Merutka","orcid":"0000-0003-0612-7400","position":5,"is_corresponding":false},{"id":1052987,"name":"Shandee D Dixon","orcid":"0000-0002-6013-0080","position":6,"is_corresponding":false},{"id":777229,"name":"Anthony Shumate","orcid":"0000-0002-8180-9893","position":7,"is_corresponding":false},{"id":1053496,"name":"Abigail R Groncki","orcid":null,"position":8,"is_corresponding":false},{"id":664677,"name":"Matthew AH Parson","orcid":"0000-0001-6270-559X","position":9,"is_corresponding":false},{"id":282789,"name":"Jessica R. Ingram","orcid":"0000-0003-1294-0270","position":10,"is_corresponding":false},{"id":279587,"name":"Eric Barklis","orcid":"0000-0003-4944-6671","position":11,"is_corresponding":false},{"id":245413,"name":"John E. Burke","orcid":"0000-0001-7904-9859","position":12,"is_corresponding":false},{"id":344407,"name":"Ujwal Shinde","orcid":"0000-0001-6229-2609","position":13,"is_corresponding":false},{"id":245647,"name":"Hidde L. Ploegh","orcid":"0000-0002-1090-6071","position":14,"is_corresponding":false},{"id":279588,"name":"Fikadu Tafesse","orcid":"0000-0002-8575-4164","position":15,"is_corresponding":false},{"id":559390,"name":"Timothy A. Bates","orcid":"0000-0002-2533-7668","position":0,"is_corresponding":true}],"reference_count":91,"raw_metadata":null,"created_at":"2026-07-19T01:09:05.843139Z","pmid":"38805257","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":[]}