{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,16]],"date-time":"2025-10-16T20:06:21Z","timestamp":1760645181745},"reference-count":0,"publisher":"Proceedings of the National Academy of Sciences","issue":"12","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1976,12]]},"abstract":"<jats:p>To identify possible substrate-binding subunit(s) of yeast cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1-9-3-1), the purified enzyme was reacted with yeast iso-1-cytochrome c whose single free sulfhydryl group at position 107 had been activated with 5,5'-dithiobis(2-nitrobenzoate). The resulting cytochrome c derivative appeared to function as an \"affinity-label\" of cytochrome oxidase, since it rapidly inactivated the enzyme. Inactivation was competitively prevented by underivatized cytochrome c. When the \"affinity-labeled\" oxidase was analyzed by two-dimensional polyacrylamide electrophoresis in dodecyl sulfate (separation in the second dimension being carried out in the presence of excess sulfhydryl compound), it was found that the derivatized cytochrome c had specifically formed a mixed disulfide with the mitochondrially made subunit III (apparent molecular weight 24,000) of the oxidase. Similar results were obtained when underivatized iso-I-cytochrome c was crosslinked to the oxidase by oxidative disulfide bridge formation in the presence of ortho-phenanthroline and Cu++. These data indicate that the hydrophobic mitochondrially made subunit III of yeast cytochrome c oxidase is in close proximity to the cytochrome c binding site on the enzyme. Since cytochrome c and the mitochondrially made cytochrome oxidase subunit III are typical peripheral and integral membrane proteins, respectively, the present study suggests a useful approach for analyzing specific interactions between these different classes of membrane proteins.<\/jats:p>","DOI":"10.1073\/pnas.73.12.4334","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T07:13:49Z","timestamp":1149059629000},"page":"4334-4338","update-policy":"http:\/\/dx.doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":54,"title":["Interaction of integral and peripheral membrane proteins: affinity labeling of yeast cytochrome oxidase by modified yeast cytochrome c."],"prefix":"10.1073","volume":"73","author":[{"given":"W","family":"Birchmeier","sequence":"first","affiliation":[]},{"given":"C E","family":"Kohler","sequence":"additional","affiliation":[]},{"given":"G","family":"Schatz","sequence":"additional","affiliation":[]}],"member":"341","published-online":{"date-parts":[[1976,12]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.73.12.4334","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T14:58:02Z","timestamp":1649861882000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.73.12.4334"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1976,12]]},"references-count":0,"journal-issue":{"issue":"12","published-print":{"date-parts":[[1976,12]]}},"alternative-id":["10.1073\/pnas.73.12.4334"],"URL":"https:\/\/doi.org\/10.1073\/pnas.73.12.4334","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1976,12]]},"assertion":[{"value":"1976-12-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}