{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T10:37:53Z","timestamp":1773657473988,"version":"3.50.1"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1993,7,1]]},"abstract":"<jats:p>The H2-oxidation, H2-production and H-3H-exchange activities of the periplasmic hydrogenase from Desulfovibrio vulgaris (Hildenborough) were almost completely abolished by Hg(II) and the organic mercurials p-chloromercuribenzoate (pCMB) and p-hydroxymercuriphenylsulphonate. The thiol-modifying reagents N-ethylmaleimide, iodoacetate, dithionitrobenzoate and 2-nitro-5-thiocyanobenzoate had no effect on the activities. Kinetic and spectroscopic measurements suggest that inactivation by pCMB involves at least two reactions; a rapid reaction that is reversed by thiols, and a second, slower and irreversible reaction that occurs at high concentrations of the mercurial. The irreversible reaction was associated with loss of visible absorbance, indicative of a disrupted iron sulphur cluster(s). The effects on the H-3H-exchange activity indicate that the reversible modification affects the H2-activating site. Enzyme that had lost activity due to pCMB treatment, or during long-term storage, was reactivated by thiols. This reactivation was followed by a slower irreversible inactivation, as also occurred with native enzyme; the inactivation was O2 dependent and it was partly prevented by catalase, suggesting that H2O2 may be involved.<\/jats:p>","DOI":"10.1042\/bj2930237","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T21:33:18Z","timestamp":1439242398000},"page":"237-241","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Effects of thiols and mercurials on the periplasmic hydrogenase from <i>Desulfovibrio vulgaris<\/i> (Hildenborough)"],"prefix":"10.1042","volume":"293","author":[{"given":"T F","family":"Fagan","sequence":"first","affiliation":[{"name":"Department of Biochemistry, University College, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S G","family":"Mayhew","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, University College, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/293\/1\/237\/611498\/bj2930237.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/293\/1\/237\/611498\/bj2930237.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,23]],"date-time":"2021-11-23T22:31:58Z","timestamp":1637706718000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/293\/1\/237\/30237\/Effects-of-thiols-and-mercurials-on-the"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,7,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1993,7,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj2930237","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,7,1]]}}}