{"entity": "publication", "iuid": "2b6897bb0221436eb22bbff20dfe0839", "timestamp": "2026-11-09T14:37:10.093Z", "links": {"self": {"href": "https://publications.scilifelab.se/publication/2b6897bb0221436eb22bbff20dfe0839.json"}, "display": {"href": "https://publications.scilifelab.se/publication/2b6897bb0221436eb22bbff20dfe0839"}}, "title": "The Mycobacterium smegmatis bd-II terminal oxidase employs a carboxylate shift mechanism.", "authors": [{"family": "Kovalova", "given": "Terezia", "initials": "T", "orcid": "0000-0002-0144-2463", "researcher": {"href": "https://publications.scilifelab.se/researcher/28a04987c43944d788c125a1dfd15828.json"}}, {"family": "Janczak", "given": "Mateusz", "initials": "M", "orcid": "0009-0004-2291-8282", "researcher": {"href": "https://publications.scilifelab.se/researcher/b889c580d7e14eb99582fb79e78c49fe.json"}}, {"family": "Gamiz-Hernandez", "given": "Ana P", "initials": "AP", "orcid": "0000-0002-0961-328X", "researcher": {"href": "https://publications.scilifelab.se/researcher/8021ee901c9442e792bba76d38984d4a.json"}}, {"family": "Lundin", "given": "Daniel", "initials": "D", "orcid": "0000-0002-8779-6464", "researcher": {"href": "https://publications.scilifelab.se/researcher/227cc90e084348a193fee05eb23a6bf3.json"}}, {"family": "Sharma", "given": "Soni", "initials": "S"}, {"family": "Vilhj\u00e1lmsd\u00f3ttir", "given": "Johanna", "initials": "J"}, {"family": "Sj\u00f6strand", "given": "Dan", "initials": "D"}, {"family": "Kaila", "given": "Ville R I", "initials": "VRI", "orcid": "0000-0003-4464-6324", "researcher": {"href": "https://publications.scilifelab.se/researcher/cdcc63256cea406c9cb9cdaecc9cbcbe.json"}}, {"family": "H\u00f6gbom", "given": "Martin", "initials": "M", "orcid": "0000-0001-5574-9383", "researcher": {"href": "https://publications.scilifelab.se/researcher/d968fcccace74b689185bb9fa2d33bf8.json"}}, {"family": "\u00c4delroth", "given": "Pia", "initials": "P", "orcid": "0000-0003-0853-6785", "researcher": {"href": "https://publications.scilifelab.se/researcher/b798b3a524114a62b4132d17cb34f8ea.json"}}], "type": "journal article", "published": "2026-03-17", "journal": {"title": "Proc. Natl. Acad. Sci. U.S.A.", "issn": "1091-6490", "volume": "123", "issue": "11", "pages": "e2515348123", "issn-l": "0027-8424"}, "abstract": "Cytochrome bd is a terminal oxidase expressed under low oxygen conditions and central for the survival of many pathogens. Here, we characterize the cyt bd-II from , a member of a hitherto uncharacterized evolutionary group (qOR-2) of Mycobacterium smegmatisbd oxidases, by combining biochemical studies with cryo-electron microscopy (cryo-EM), and multiscale simulations. Overexpressing the appCB operon in its native host led to production of a highly active bd-II (kobs = 30 e- s-1) that together with a high-resolution (2.8 \u00c5) cryo-EM structure and multiscale simulations reveal unique proton pathways and oxygen channels responsible for its function. We propose that a pH-dependent molecular switch, involving coordination changes of heme d and surrounding bulky residues regulate substrate access into the active site. Taken together, our findings provide detailed mechanistic insight of qOR-2 type bd oxidases, and a basis for understanding the evolution of the superfamily.", "doi": "10.1073/pnas.2515348123", "pmid": "41805574", "labels": {"Cryo-EM": "Service"}, "xrefs": [{"db": "pmc", "key": "PMC12994193"}], "notes": [], "created": "2026-11-05T15:02:37.461Z", "modified": "2026-11-05T15:02:37.633Z"}