{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T16:49:31Z","timestamp":1790873371931,"version":"4.1.0"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1994,10,1]]},"abstract":"<jats:p>N-chlorosuccinimide oxidizes one of the methionine residues of mucus proteinase inhibitor with a second-order rate constant of 1.5 M-1.s-1. Cyanogen bromide cleavage and NH2-terminal sequencing show that the modified residue is methionine-73, the P\u20321 component of the inhibitor's active centre. Oxidation of the inhibitor decreases its neutrophil elastase inhibitory capacity but does not fully abolish it. The kinetic parameters describing the elastase-oxidized inhibitor interaction are: association rate constant kass. = 2.6 x 10(5) M-1.s-1, dissociation rate constant kdiss. = 2.9 x 10(-3) s-1 and equilibrium dissociation constant Ki = 1.1 x 10(-8) M. Comparison with the native inhibitor indicates that oxidation decreases kass. by a factor of 18.8 and increases kdiss. by a factor of 6.4, and therefore leads to a 120-fold increase in Ki. Yet, the oxidized inhibitor may still act as a potent elastase inhibitor in the upper respiratory tract where its concentration is 500-fold higher than Ki, i.e. where the elastase inhibition is pseudo-irreversible. Experiments in vitro with fibrous human lung elastin, the most important natural substrate of elastase, support this view: 1.35 microM elastase is fully inhibited by 5-6 microM oxidized inhibitor whether the enzyme-inhibitor complex is formed in the presence or absence of elastin and whether elastase is pre-adsorbed on elastin or not.<\/jats:p>","DOI":"10.1042\/bj3030061","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T21:40:01Z","timestamp":1439242801000},"page":"61-68","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Oxidized mucus proteinase inhibitor: a fairly potent neutrophil elastase inhibitor"],"prefix":"10.1042","volume":"303","author":[{"given":"C","family":"Boudier","sequence":"first","affiliation":[{"name":"Laboratoire d'Enzymologie, INSERM Unit\u00e9 237, Universit\u00e9 Louis Pasteur de Strasbourg, F-67400 Illkirch, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J G","family":"Bieth","sequence":"additional","affiliation":[{"name":"Laboratoire d'Enzymologie, INSERM Unit\u00e9 237, Universit\u00e9 Louis Pasteur de Strasbourg, F-67400 Illkirch, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/303\/1\/61\/614925\/bj3030061.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/303\/1\/61\/614925\/bj3030061.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,23]],"date-time":"2021-11-23T23:13:36Z","timestamp":1637709216000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/303\/1\/61\/31207\/Oxidized-mucus-proteinase-inhibitor-a-fairly"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1994,10,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1994,10,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj3030061","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1994,10,1]]}}}