{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,13]],"date-time":"2026-09-13T02:25:53Z","timestamp":1789266353266,"version":"build-2803163510"},"reference-count":0,"publisher":"American Society for Microbiology","issue":"1","license":[{"start":{"date-parts":[[1986,1,1]],"date-time":"1986-01-01T00:00:00Z","timestamp":504921600000},"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":[[1986,1]]},"abstract":"<jats:p>A novel beta-lactamase, which had a pI of 6.5 and a molecular weight of 25,000, was observed in two Pseudomonas aeruginosa isolates. The enzyme, designated NPS-1, was encoded by a plasmid of molecular weight 41 X 10(6) which also encoded resistance to streptomycin and sulfonamide. This plasmid, designated pMLH50, was freely transmissible to other P. aeruginosa strains, but not to Escherichia coli K-12. The enzyme was purified partially and shown to have activity against both penicillins and cephalosporins. Vmax rates for oxacillin and carbenicillin were less than 50% of the Vmax for benzylpenicillin, and the Vmax for cephaloridine was only 3% of the Vmax for benzylpenicillin. Imipenem, aztreonam, and several antipseudomonal cephalosporins were stable to the enzyme. Hydrolysis of most substrates obeyed Michaelis-Menten kinetics, but cefsulodin induced a reversible reduction in the activity of the enzyme. Transconjugants of the beta-lactamase-producing isolates in P. aeruginosa PU21 acquired beta-lactam resistances which mirrored the hydrolytic activity of the enzyme.<\/jats:p>","DOI":"10.1128\/aac.29.1.99","type":"journal-article","created":{"date-parts":[[2012,6,28]],"date-time":"2012-06-28T00:04:52Z","timestamp":1340841892000},"page":"99-103","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":27,"title":["Characterization of NPS-1, a novel plasmid-mediated beta-lactamase, from two Pseudomonas aeruginosa isolates"],"prefix":"10.1128","volume":"29","author":[{"given":"D M","family":"Livermore","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C S","family":"Jones","sequence":"additional","affiliation":[],"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.29.1.99","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.29.1.99","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T14:34:34Z","timestamp":1645454074000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/AAC.29.1.99"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1986,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1986,1]]}},"alternative-id":["10.1128\/AAC.29.1.99"],"URL":"https:\/\/doi.org\/10.1128\/aac.29.1.99","relation":{},"ISSN":["0066-4804","1098-6596"],"issn-type":[{"value":"0066-4804","type":"print"},{"value":"1098-6596","type":"electronic"}],"subject":[],"published":{"date-parts":[[1986,1]]},"assertion":[{"value":"1986-01-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}