{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:08:06Z","timestamp":1791331686564,"version":"4.3.1"},"reference-count":0,"publisher":"American Society for Microbiology","issue":"5","license":[{"start":{"date-parts":[[1993,5,1]],"date-time":"1993-05-01T00:00:00Z","timestamp":736214400000},"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":[[1993,5]]},"abstract":"<jats:p>A clinical isolate of Enterobacter cloacae, strain NOR-1, exhibited resistance to imipenem and remained susceptible to extended-spectrum cephalosporins. Clavulanic acid partially restored the susceptibility of the strain to imipenem. Two beta-lactamases with isoelectric points (pI) of 6.9 and &gt; 9.2 were detected in strain E. cloacae NOR-1; the higher pI corresponded to AmpC cephalosporinase. Plasmid DNA was not detected in E. cloacae NOR-1 and imipenem resistance could not be transferred into Escherichia coli JM109. The carbapenem-hydrolyzing beta-lactamase gene was cloned into plasmid pACYC184. One recombinant plasmid, pPTN1, harbored a 5.3-kb Sau3A fragment from E. cloacae NOR-1 expressing the carbapenem-hydrolyzing beta-lactamase. This enzyme (pI 6.9) hydrolyzed ampicillin, cephalothin, and imipenem more rapidly than it did meropenem and aztreonam, but it hydrolyzed extended-spectrum cephalosporins only weakly and did not hydrolyze cefoxitin. Hydrolytic activity was partially inhibited by clavulanic acid, sulbactam, and tazobactam, was nonsusceptible to chelating agents such as EDTA and 1,10-o-phenanthroline, and was independent of the presence of ZnCl2. Its relative molecular mass was 30,000 Da. Induction experiments concluded that the carbapenem-hydrolyzing beta-lactamase biosynthesis was inducible by cefoxitin and imipenem. Subcloning experiments with HindIII partial digests of pPTN1 resulted in a recombinant plasmid, designated pPTN2, which contained a 1.3-kb insert from pPTN1 and which conferred resistance to beta-lactam antibiotics. Hybridization studies performed with a 1.2-kb HindIII fragment from pPtN2 failed to determine any homology with ampC of E. cloacae, with other known beta-lactamase genes commonly found in members of the family Enterobacteriaceae (bla(TEM-1)) and bla(SHV-3) derivatives), and with previously described carbapenemase genes such as those from Xanthomonas maltophilia, Bacillus cereus, Bacteroides fragilis (cfiA), and Aeromonas hydrophila (cphA). This work describing the biochemical properties of a novel chromosome-encoded beta-lactamase from E. cloacae indicates that this enzyme differs from all the previously described carbapenemases. This is the first reported cloning of a carbapenem-hydrolyzing gene from a member of the family Enterobacteriaceae.<\/jats:p>","DOI":"10.1128\/aac.37.5.939","type":"journal-article","created":{"date-parts":[[2012,6,28]],"date-time":"2012-06-28T00:05:50Z","timestamp":1340841950000},"page":"939-946","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":137,"title":["Biochemical properties of a carbapenem-hydrolyzing beta-lactamase from Enterobacter cloacae and cloning of the gene into Escherichia coli"],"prefix":"10.1128","volume":"37","author":[{"given":"P","family":"Nordmann","sequence":"first","affiliation":[{"name":"Laboratoire de Microbiologie, H\u00f4pital Raymond Poincar\u00e9, Facult\u00e9 de M\u00e9decine Paris-Ouest, Garches, France."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S","family":"Mariotte","sequence":"additional","affiliation":[{"name":"Laboratoire de Microbiologie, H\u00f4pital Raymond Poincar\u00e9, Facult\u00e9 de M\u00e9decine Paris-Ouest, Garches, France."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T","family":"Naas","sequence":"additional","affiliation":[{"name":"Laboratoire de Microbiologie, H\u00f4pital Raymond Poincar\u00e9, Facult\u00e9 de M\u00e9decine Paris-Ouest, Garches, France."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Labia","sequence":"additional","affiliation":[{"name":"Laboratoire de Microbiologie, H\u00f4pital Raymond Poincar\u00e9, Facult\u00e9 de M\u00e9decine Paris-Ouest, Garches, France."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M H","family":"Nicolas","sequence":"additional","affiliation":[{"name":"Laboratoire de Microbiologie, H\u00f4pital Raymond Poincar\u00e9, Facult\u00e9 de M\u00e9decine Paris-Ouest, Garches, France."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","container-title":["Antimicrobial Agents and Chemotherapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.37.5.939","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.37.5.939","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T15:33:52Z","timestamp":1645457632000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/AAC.37.5.939"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,5]]},"references-count":0,"journal-issue":{"issue":"5","published-print":{"date-parts":[[1993,5]]}},"alternative-id":["10.1128\/AAC.37.5.939"],"URL":"https:\/\/doi.org\/10.1128\/aac.37.5.939","relation":{},"ISSN":["0066-4804","1098-6596"],"issn-type":[{"value":"0066-4804","type":"print"},{"value":"1098-6596","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,5]]},"assertion":[{"value":"1993-05-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}