{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:56:38Z","timestamp":1785405398352,"version":"3.56.0"},"reference-count":69,"publisher":"American Society for Microbiology","issue":"5","license":[{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["J Bacteriol"],"published-print":{"date-parts":[[2026,5,21]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      Mycobacteria have a hydrophobic cell envelope that makes uniform growth in liquid culture challenging. Non-ionic detergents, including Tween-80 and tyloxapol, are commonly added to media when culturing mycobacterial species in the laboratory. Tyloxapol was reported to exhibit anti-tuberculous activity during animal infection with\n                      <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                      in the 1950s. In the 1980s, microscopy studies suggested that tyloxapol impacted the interaction between\n                      <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                      and the phagosomal membrane, preventing mycobacterial access to the cytoplasm. It is now known that the ESX-1 Type VII secretion system mediates the interaction between pathogenic mycobacteria and the phagosomal membrane.\n                      <jats:italic toggle=\"yes\">Mycobacterium marinum<\/jats:italic>\n                      is a pathogenic mycobacterial species that has been widely used to understand the molecular mechanisms and host responses to the ESX-1 system. The hemolytic activity of\n                      <jats:italic toggle=\"yes\">M. marinum<\/jats:italic>\n                      allows the study of ESX-1 lytic activity outside of the context of a host cell. We found that tyloxapol inhibits the hemolytic activity of\n                      <jats:italic toggle=\"yes\">M. marinum<\/jats:italic>\n                      in a concentration-dependent manner. We discovered the mechanism underlying the inhibition of hemolysis is the differential inhibition of the production and secretion of ESX-1 substrates. Proteomics analysis indicates that tyloxapol specifically inhibited the secretion of a subset of ESX-1 substrates in addition to specific PE\/PPE\/PEGRS proteins, but not the secretion of proteins secreted by the Sec, ESX-3, or ESX-5 secretion systems. Our findings directly impact how the field interprets data from studies where\n                      <jats:italic toggle=\"yes\">M. marinum<\/jats:italic>\n                      , and potentially other mycobacterial species, were grown in tyloxapol. Our findings may explain the original observations linking tyloxapol to anti-tuberculosis activity.\n                    <\/jats:p>\n                    <jats:sec>\n                      <jats:title>IMPORTANCE<\/jats:title>\n                      <jats:p>\n                        Tuberculosis, which is caused by\n                        <jats:italic toggle=\"yes\">Mycobacterium tuberculosis<\/jats:italic>\n                        , is one of the world\u2019s deadliest diseases. We lack a clear understanding of how\n                        <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                        and related mycobacterial species cause disease. In the 1950s, it was reported that treating\n                        <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                        -infected animals with tyloxapol improved the survival and, in some cases, protected the animals from death. Tyloxapol is a detergent that is commonly added to mycobacterial cultures to promote dispersed growth in the laboratory. Later studies suggested that tyloxapol altered the interaction between\n                        <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                        and the phagosomal membrane during macrophage infection. The ability to escape the phagosome is essential for mycobacteria to cause disease and is mediated by the ESX-1 Type VII protein secretion system. Using\n                        <jats:italic toggle=\"yes\">M. marinum<\/jats:italic>\n                        , a well-established model for understanding the molecular mechanisms of ESX-1 secretion, we show that tyloxapol used at more than 100-fold less than what is commonly used to grow mycobacteria in the lab inhibits ESX-1 secretion. Our findings have widespread implications on how we interpret our findings as a field and may explain why tyloxapol impacted\n                        <jats:italic toggle=\"yes\">M. tuberculosis<\/jats:italic>\n                        infection of both animals and macrophages. Our study also indicates that tyloxapol can be used as a tool to understand the molecular mechanisms of ESX-1 protein secretion.\n                      <\/jats:p>\n                    <\/jats:sec>\n                  <\/jats:sec>","DOI":"10.1128\/jb.00136-26","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T13:16:35Z","timestamp":1776863795000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":1,"title":["Tyloxapol inhibits ESX-1 secretion in\n                    <i>Mycobacterium marinum<\/i>"],"prefix":"10.1128","volume":"208","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-1736-5770","authenticated-orcid":false,"given":"Owen A.","family":"Collars","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biological Sciences, University of Notre Dame","place":["Notre Dame, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4354-0309","authenticated-orcid":true,"given":"Simon D.","family":"Weaver","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biological Sciences, University of Notre Dame","place":["Notre Dame, USA"]},{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Chemistry and Biochemistry, University of Notre Dame","place":["Notre Dame, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6631-5944","authenticated-orcid":false,"given":"Richard L.","family":"Hernandez","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biological Sciences, University of Notre Dame","place":["Notre Dame, USA"]},{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Chemistry and Biochemistry, University of Notre Dame","place":["Notre Dame, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5927-5277","authenticated-orcid":true,"given":"Matthew M.","family":"Champion","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Chemistry and Biochemistry, University of Notre Dame","place":["Notre Dame, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6733-596X","authenticated-orcid":true,"given":"Patricia A.","family":"Champion","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/009yjbg58","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biological Sciences, University of Notre Dame","place":["Notre Dame, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_5_2_2","doi-asserted-by":"publisher","DOI":"10.1084\/jem.134.3.713"},{"key":"e_1_3_5_3_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M800123200"},{"key":"e_1_3_5_4_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1462-5822.2009.01335.x"},{"key":"e_1_3_5_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cell.2007.05.059"},{"key":"e_1_3_5_6_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1002507"},{"key":"e_1_3_5_7_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1462-5822.2012.01799.x"},{"key":"e_1_3_5_8_2","doi-asserted-by":"publisher","DOI":"10.1084\/jem.20031072"},{"key":"e_1_3_5_9_2","doi-asserted-by":"publisher","DOI":"10.4049\/jimmunol.178.5.3143"},{"key":"e_1_3_5_10_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.chembiol.2023.04.014"},{"key":"e_1_3_5_11_2","doi-asserted-by":"publisher","DOI":"10.1038\/168150a0"},{"key":"e_1_3_5_12_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1476-5381.1955.tb00063.x"},{"key":"e_1_3_5_13_2","doi-asserted-by":"publisher","DOI":"10.1164\/art.1952.65.6.718"},{"key":"e_1_3_5_14_2","first-page":"581","article-title":"Antituberculous activity of certain non-ionic detergents","volume":"46","author":"Rees RJ","year":"1953","unstructured":"Rees RJ. 1953. Antituberculous activity of certain non-ionic detergents. Proc R Soc Med 46:581\u2013583.","journal-title":"Proc R Soc Med"},{"key":"e_1_3_5_15_2","doi-asserted-by":"publisher","DOI":"10.7883\/yoken1952.39.49"},{"key":"e_1_3_5_16_2","doi-asserted-by":"publisher","DOI":"10.7883\/yoken1952.39.35"},{"key":"e_1_3_5_17_2","doi-asserted-by":"publisher","DOI":"10.1038\/nrmicro1773"},{"key":"e_1_3_5_18_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2235593100"},{"key":"e_1_3_5_19_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2958.2003.03844.x"},{"key":"e_1_3_5_20_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1635213100"},{"key":"e_1_3_5_21_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2958.2004.04261.x"},{"key":"e_1_3_5_22_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.86.5.1057-1069.1963"},{"key":"e_1_3_5_23_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.coi.2004.05.011"},{"key":"e_1_3_5_24_2","doi-asserted-by":"publisher","DOI":"10.1128\/MMBR.00082-19"},{"key":"e_1_3_5_25_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2958.2002.03237.x"},{"key":"e_1_3_5_26_2","doi-asserted-by":"publisher","DOI":"10.1086\/345862"},{"key":"e_1_3_5_27_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0900589106"},{"key":"e_1_3_5_28_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2958.2006.05409.x"},{"key":"e_1_3_5_29_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.00756-09"},{"key":"e_1_3_5_30_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1003734"},{"key":"e_1_3_5_31_2","doi-asserted-by":"publisher","DOI":"10.1128\/mBio.01073-14"},{"key":"e_1_3_5_32_2","doi-asserted-by":"publisher","DOI":"10.1038\/nmicrobiol.2016.232"},{"key":"e_1_3_5_33_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1523321113"},{"key":"e_1_3_5_34_2","doi-asserted-by":"publisher","DOI":"10.1128\/mbio.01044-25"},{"key":"e_1_3_5_35_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.aav5912"},{"key":"e_1_3_5_36_2","doi-asserted-by":"publisher","unstructured":"Block AM Nair RR Meikle V Wiegert PC White DW Zhang L Niederweis M Tischler AD. 2025. The Mycobacterium tuberculosis ESX-5 secretion system enables carbon source utilization and growth in mice. bioRxiv:2025.10.28.685107. doi:10.1101\/2025.10.28.685107","DOI":"10.1101\/2025.10.28.685107"},{"key":"e_1_3_5_37_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pgen.1005190"},{"key":"e_1_3_5_38_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.00212-22"},{"key":"e_1_3_5_39_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2958.2012.08001.x"},{"key":"e_1_3_5_40_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.00827-15"},{"key":"e_1_3_5_41_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1005696"},{"key":"e_1_3_5_42_2","doi-asserted-by":"publisher","DOI":"10.1128\/mBio.02983-20"},{"key":"e_1_3_5_43_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.00653-16"},{"key":"e_1_3_5_44_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2123100119"},{"key":"e_1_3_5_45_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.00289-20"},{"key":"e_1_3_5_46_2","doi-asserted-by":"publisher","DOI":"10.1084\/jem.88.1.81"},{"key":"e_1_3_5_47_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.tube.2016.07.002"},{"key":"e_1_3_5_48_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.mimet.2019.105795"},{"key":"e_1_3_5_49_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.mimet.2024.107028"},{"key":"e_1_3_5_50_2","doi-asserted-by":"publisher","DOI":"10.1128\/iai.59.6.1905-1910.1991"},{"key":"e_1_3_5_51_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.187.4.1238-1245.2005"},{"key":"e_1_3_5_52_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1710167114"},{"key":"e_1_3_5_53_2","doi-asserted-by":"publisher","DOI":"10.1128\/mBio.02807-19"},{"key":"e_1_3_5_54_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.00233-22"},{"key":"e_1_3_5_55_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.0030105"},{"key":"e_1_3_5_56_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.74.1.88-98.2006"},{"key":"e_1_3_5_57_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1000285"},{"key":"e_1_3_5_58_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0211003"},{"key":"e_1_3_5_59_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.1131167"},{"key":"e_1_3_5_60_2","doi-asserted-by":"publisher","DOI":"10.1021\/pr500484w"},{"key":"e_1_3_5_61_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41564-024-01697-8"},{"key":"e_1_3_5_62_2","doi-asserted-by":"publisher","DOI":"10.1128\/iai.64.4.1491-1493.1996"},{"key":"e_1_3_5_63_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.162.3854.686"},{"key":"e_1_3_5_64_2","first-page":"403","article-title":"The effect of macrocyclon on the multiplication of tubercle bacilli in the lungs and spleen of mice","volume":"41","author":"Niffenegger J","year":"1960","unstructured":"Niffenegger J, Youmans GP. 1960. The effect of macrocyclon on the multiplication of tubercle bacilli in the lungs and spleen of mice. Br J Exp Pathol 41:403\u2013413.","journal-title":"Br J Exp Pathol"},{"key":"e_1_3_5_65_2","first-page":"414","article-title":"Effect of macrocyclon in acute and chronic pulmonary tuberculous infection in mice as shown by viable and total bacterial counts","volume":"41","author":"Hart PD","year":"1960","unstructured":"Hart PD, Rees RJ. 1960. Effect of macrocyclon in acute and chronic pulmonary tuberculous infection in mice as shown by viable and total bacterial counts. Br J Exp Pathol 41:414\u2013421.","journal-title":"Br J Exp Pathol"},{"key":"e_1_3_5_66_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0153079"},{"key":"e_1_3_5_67_2","doi-asserted-by":"publisher","unstructured":"Collars OA Hernandez RL Weaver SD Prest RJ Manu C Viswanathan G Cronin RM Jones BS Tobin DM Champion MM Champion PA. 2026. pH-responsive substrate switching in mycobacterial type VII ESX secretion. bioRxiv:2026.02.04.703728. doi:10.64898\/2026.02.04.703728","DOI":"10.64898\/2026.02.04.703728"},{"key":"e_1_3_5_68_2","doi-asserted-by":"publisher","DOI":"10.1128\/mbio.00987-23"},{"key":"e_1_3_5_69_2","doi-asserted-by":"publisher","DOI":"10.1128\/msphere.00005-24"},{"key":"e_1_3_5_70_2","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/gkv007"}],"container-title":["Journal of Bacteriology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/jb.00136-26","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/jb.00136-26","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T13:02:34Z","timestamp":1780664554000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/jb.00136-26"}},"subtitle":[],"editor":[{"given":"George","family":"O'Toole","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,5,21]]},"references-count":69,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2026,5,21]]}},"alternative-id":["10.1128\/jb.00136-26"],"URL":"https:\/\/doi.org\/10.1128\/jb.00136-26","relation":{"has-preprint":[{"id-type":"doi","id":"10.64898\/2026.02.02.703260","asserted-by":"object"}]},"ISSN":["0021-9193","1098-5530"],"issn-type":[{"value":"0021-9193","type":"print"},{"value":"1098-5530","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,21]]},"assertion":[{"value":"2026-03-03","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-03-09","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-04-22","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e00136-26"}}