{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T15:59:04Z","timestamp":1762271944888},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1978,1,1]]},"abstract":"<jats:p>Reversible competitive inhibitors of a penicillinase, beta-lactamase 1 from Bacillus cereus, were studied. These represent the first inhibitors of a penicillinase that lack the beta-lactam ring. The products of the enzymic reaction, namely penicilloic acids, are inhibitors; their decarboxylation products, the penilloic acids, are also inhibitors, and have somewhat lower Ki values. Inhibitors have been prepared from benzylpenicillin, phenoxymethyl-penicillin, methicillin (2,6-dimethoxybenzamidopenicillanic acid) and 3-hydroxy-4-nitrobenzamidopenicillanic acid. Decarboxylation of the penicilloic acids from benzyl-penicillin, or from phenoxymethylpenicillin, leads to epimerization (at C-5) of the penilloic acid. Nuclear-magnetic resonance spectroscopy at a frequency of 270 MHz can distinguish the epimers. Other competitive inhibitors studied were boric acid, benzene boronic acid and m-aminobenzeneboronic acid. Boric acid itself was the best inhibitor of beta-lactamase I so far found.<\/jats:p>","DOI":"10.1042\/bj1690197","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T20:09:42Z","timestamp":1439237382000},"page":"197-204","update-policy":"http:\/\/dx.doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":98,"title":["Reversible inhibitors of penicillinases"],"prefix":"10.1042","volume":"169","author":[{"given":"P A","family":"Kiener","sequence":"first","affiliation":[]},{"given":"S G","family":"Waley","sequence":"additional","affiliation":[]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/169\/1\/197\/619154\/bj1690197.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/169\/1\/197\/619154\/bj1690197.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T17:43:06Z","timestamp":1637948586000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/169\/1\/197\/11442\/Reversible-inhibitors-of-penicillinases"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1978,1,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1978,1,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj1690197","relation":{},"ISSN":["0264-6021"],"issn-type":[{"value":"0264-6021","type":"print"}],"subject":[],"published":{"date-parts":[[1978,1,1]]}}}