{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,19]],"date-time":"2025-09-19T11:05:25Z","timestamp":1758279925040},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1980,5,1]]},"abstract":"<jats:p>The binding constants of substrate, inhibitors and coenzymes to native Lactobacillus casei dihydrofolate reductase and to the enzyme modified (at Trp-21) by N-bromosuccinimide have been determined using fluorimetric and spectrophotometric methods. The modification leads to only modest decreases (factors of 2-4) in the binding of substrate or substrate analogues, but the effects of coenzyme binding are much larger. The binding of NADPH is decreased by a factor of 200, but that of NADP+ by only a factor of 4, indicating a clear difference in their mode of interaction with the enzyme. The nature of this difference is discussed in the light of crystallographic and n.m.r. studies of the enzyme.<\/jats:p>","DOI":"10.1042\/bj1870501","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T20:22:05Z","timestamp":1439238125000},"page":"501-506","update-policy":"http:\/\/dx.doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["The effects of modification with <i>N<\/i>-bromosuccinimide on the binding of ligands to dihydrofolate reductase"],"prefix":"10.1042","volume":"187","author":[{"given":"J W","family":"Thomson","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G C","family":"Roberts","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A S","family":"Burgen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/187\/2\/501\/574034\/bj1870501.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/187\/2\/501\/574034\/bj1870501.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T13:53:07Z","timestamp":1637934787000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/187\/2\/501\/5443\/The-effects-of-modification-with-N"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1980,5,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1980,5,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj1870501","relation":{},"ISSN":["0264-6021"],"issn-type":[{"value":"0264-6021","type":"print"}],"subject":[],"published":{"date-parts":[[1980,5,1]]}}}