{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T08:02:11Z","timestamp":1761292931647},"reference-count":0,"publisher":"American Society for Microbiology","issue":"3","license":[{"start":{"date-parts":[[1976,9,1]],"date-time":"1976-09-01T00:00:00Z","timestamp":210384000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Antimicrob Agents Chemother"],"published-print":{"date-parts":[[1976,9]]},"abstract":"<jats:p>\n            Selected cephalosporins, including cefamandole, cephaloridine, cephaloglycin, and cefoxitin, were examined for their ability to inhibit the enzymatic activity of and act as substrates for beta-lactamases produced by\n            <jats:italic>Enterobacter cloacae<\/jats:italic>\n            and\n            <jats:italic>Staphylococcus aureus<\/jats:italic>\n            . Enzyme inhibition was determined by Michaelis-Menten kinetic measurements and by a spot plate assay using a chromogenic substrate (Glaxo compound 87\/312). These two methods provide comparable estimates of kinetic parameters. Inhibition of beta-lactamase, as measured by these two methods, was generally found to correlate with resistance to hydrolysis and is proposed as a preliminary method of assessing susceptibility of cephalosporins to beta-lactamase hydrolysis. Four 7-\u03b1OCH\n            <jats:sub>3<\/jats:sub>\n            , 7-\u03b1H cephalosporin analogue pairs were also examined. The presence of the 7-\u03b1OCH\n            <jats:sub>3<\/jats:sub>\n            substituent invariably resulted in reduced susceptibility to enzymatic hydrolysis, regardless of the other C7 substituent. The 7-\u03b1OCH\n            <jats:sub>3<\/jats:sub>\n            compounds were also better inhibitors than were their 7-\u03b1H analogues, with the exception that 7-\u03b1OCH\n            <jats:sub>3<\/jats:sub>\n            compounds having C7 adipic acid substituents were less inhibitory to the\n            <jats:italic>S. aureus<\/jats:italic>\n            enzyme than were the corresponding 7-\u03b1H analogues. Response of these two enzymes to 7-\u03b1OCH\n            <jats:sub>3<\/jats:sub>\n            and 7-\u03b1H cephalosporins suggests that beta-lactamase hydrolysis of these compounds involves attack at the alpha side of the betalactam ring.\n          <\/jats:p>","DOI":"10.1128\/aac.10.3.470","type":"journal-article","created":{"date-parts":[[2012,6,27]],"date-time":"2012-06-27T23:57:02Z","timestamp":1340841422000},"page":"470-475","update-policy":"http:\/\/dx.doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":13,"title":["Substrate Inhibition of Beta-Lactamases, a Method for Predicting Enzymatic Stability of Cephalosporins"],"prefix":"10.1128","volume":"10","author":[{"given":"David F.","family":"Mahoney","sequence":"first","affiliation":[{"name":"Lilly Research Laboratories, Eli Lilly &amp; Co., Indianapolis, Indiana 46206"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G. A.","family":"Koppel","sequence":"additional","affiliation":[{"name":"Lilly Research Laboratories, Eli Lilly &amp; Co., Indianapolis, Indiana 46206"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J. R.","family":"Turner","sequence":"additional","affiliation":[{"name":"Lilly Research Laboratories, Eli Lilly &amp; Co., Indianapolis, Indiana 46206"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"235","container-title":["Antimicrobial Agents and Chemotherapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.10.3.470","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.10.3.470","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T13:32:31Z","timestamp":1645450351000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/AAC.10.3.470"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1976,9]]},"references-count":0,"journal-issue":{"issue":"3","published-print":{"date-parts":[[1976,9]]}},"alternative-id":["10.1128\/AAC.10.3.470"],"URL":"https:\/\/doi.org\/10.1128\/aac.10.3.470","relation":{},"ISSN":["0066-4804","1098-6596"],"issn-type":[{"value":"0066-4804","type":"print"},{"value":"1098-6596","type":"electronic"}],"subject":[],"published":{"date-parts":[[1976,9]]},"assertion":[{"value":"1976-09-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}