{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T14:31:26Z","timestamp":1790865086816,"version":"4.1.0"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1995,6,1]]},"abstract":"<jats:p>Knowledge of the kinetics of the rod cyclic GMP phosphodiesterase is essential for understanding the kinetics and gain of the light response. Therefore, the interactions between Mg2+, cyclic GMP, and purified, trypsin-activated bovine rod cyclic GMP phosphodiesterase (EC 3.1.4.17) were examined. The effects of Mg2+ and of cyclic GMP on the rod phosphodiesterase activity were mutually concentration-dependent. Formation of a free Mg-cyclic GMP complex is unlikely due to its high dissociation constant (Kd = 19 mM). Plots of 1\/velocity versus 1\/[cyclic GMP] as a function of [Mg2+] and 1\/velocity versus 1\/[Mg2+] as a function of [cyclic GMP] intersected to the left of the 1\/velocity axis. This is consistent with the formation of a ternary complex between the phosphodiesterase, Mg2+, and cyclic GMP. A competitive inhibitor of the phosphodiesterase relative to cyclic GMP, 3-isobutyl-1-methylxanthine, non-competitively inhibited the enzyme relative to Mg2+, Pb2+, a competitive inhibitor of the phosphodiesterase relative to Mg2+ [D. Srivastava, R.L. Hurwitz and D. A. Fox (1995) Toxicol. Appl. Pharmacol, in the press] non-competitively inhibited the enzyme relative to cyclic GMP. Collectively these results are suggestive of a rapid equilibrium random binding order of Mg2+ and cyclic GMP to the rod phosphodiesterase.<\/jats:p>","DOI":"10.1042\/bj3080653","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T21:43:44Z","timestamp":1439243024000},"page":"653-658","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Effects of magnesium on cyclic GMP hydrolysis by the bovine retinal rod cyclic GMP phosphodiesterase"],"prefix":"10.1042","volume":"308","author":[{"given":"D","family":"Srivastava","sequence":"first","affiliation":[{"name":"College of Optometry, University of Houston, TX 77204-6052, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D A","family":"Fox","sequence":"additional","affiliation":[{"name":"College of Optometry, University of Houston, TX 77204-6052, USA."},{"name":"Deparment of Biochemical and Biophysical Sciences, University of Houston, Houston, TX 77204-6052, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R L","family":"Hurwitz","sequence":"additional","affiliation":[{"name":"Departments of Pediatrics and Cell Biology, Baylor College of Medicine, Houston, TX 77030, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/308\/2\/653\/616850\/bj3080653.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/308\/2\/653\/616850\/bj3080653.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,24]],"date-time":"2021-11-24T01:04:52Z","timestamp":1637715892000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/308\/2\/653\/37641\/Effects-of-magnesium-on-cyclic-GMP-hydrolysis-by"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,6,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1995,6,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj3080653","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,6,1]]}}}