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The complex exists as an obligatory dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with cytochrome c oxidase (complex IV, CIV)"}],"commentType":"SUBUNIT"},{"commentType":"SUBCELLULAR LOCATION","subcellularLocations":[{"location":{"evidences":[{"evidenceCode":"ECO:0000250","source":"UniProtKB","id":"P08525"}],"value":"Mitochondrion inner membrane","id":"SL-0168"},"topology":{"evidences":[{"evidenceCode":"ECO:0000250","source":"UniProtKB","id":"P08525"}],"value":"Single-pass membrane protein","id":"SL-9904"}}]},{"texts":[{"evidences":[{"evidenceCode":"ECO:0000305"}],"value":"Belongs to the UQCRQ/QCR8 family"}],"commentType":"SIMILARITY"}],"features":[{"type":"Initiator methionine","location":{"start":{"value":1,"modifier":"EXACT"},"end":{"value":1,"modifier":"EXACT"}},"description":"Removed","evidences":[{"evidenceCode":"ECO:0000269","source":"PubMed","id":"7803451"}]},{"type":"Chain","location":{"start":{"value":2,"modifier":"EXACT"},"end":{"value":72,"modifier":"EXACT"}},"description":"Cytochrome b-c1 complex subunit 8","featureId":"PRO_0000193548"},{"type":"Topological domain","location":{"start":{"value":2,"modifier":"EXACT"},"end":{"value":41,"modifier":"EXACT"}},"description":"Mitochondrial matrix","evidences":[{"evidenceCode":"ECO:0000250","source":"UniProtKB","id":"P08525"}]},{"type":"Transmembrane","location":{"start":{"value":42,"modifier":"EXACT"},"end":{"value":59,"modifier":"EXACT"}},"description":"Helical","evidences":[{"evidenceCode":"ECO:0000255"}]},{"type":"Topological domain","location":{"start":{"value":60,"modifier":"EXACT"},"end":{"value":72,"modifier":"EXACT"}},"description":"Mitochondrial intermembrane","evidences":[{"evidenceCode":"ECO:0000250","source":"UniProtKB","id":"P08525"}]},{"type":"Sequence conflict","location":{"start":{"value":15,"modifier":"EXACT"},"end":{"value":15,"modifier":"EXACT"}},"description":"in Ref. 2; AA sequence","evidences":[{"evidenceCode":"ECO:0000305"}],"alternativeSequence":{"originalSequence":"I","alternativeSequences":["L"]}}],"keywords":[{"id":"KW-0903","category":"Technical term","name":"Direct protein sequencing"},{"id":"KW-0249","category":"Biological process","name":"Electron transport"},{"id":"KW-0472","category":"Cellular component","name":"Membrane"},{"id":"KW-0496","category":"Cellular component","name":"Mitochondrion"},{"id":"KW-0999","category":"Cellular component","name":"Mitochondrion inner membrane"},{"id":"KW-1185","category":"Technical term","name":"Reference proteome"},{"id":"KW-0679","category":"Biological process","name":"Respiratory chain"},{"id":"KW-0812","category":"Domain","name":"Transmembrane"},{"id":"KW-1133","category":"Domain","name":"Transmembrane helix"},{"id":"KW-0813","category":"Biological process","name":"Transport"}],"references":[{"referenceNumber":1,"citation":{"id":"7803451","citationType":"journal article","authors":["Braun H.-P.","Kruft V.","Schmitz U.K."],"citationCrossReferences":[{"database":"PubMed","id":"7803451"},{"database":"DOI","id":"10.1016/0005-2728(94)90057-4"}],"title":"Primary structure, cell-free synthesis and mitochondrial targeting of the 8.2 kDa protein of cytochrome c reductase from potato.","publicationDate":"1994","journal":"Biochim. 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