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PubMed · 16201924

Ciprofloxacin, salicylate, and 2,4-dinitrophenol decrease production of AmpC-type beta-lactamase in two Citrobacter freundii clinical isolates.

María M Tavío·Mariagrazia Perilli·Jordi Vila·Pino Becerro·Joaquím Ruiz·Gianfranco Amicosante·María T Jiménez De Anta
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Abstract

The effect of ciprofloxacin and two mar RAB inducers on the susceptibility to beta-lactam antibiotics in two AmpC beta-lactamase semi-constitutive producer Citrobacter freundii clinical isolates (the DM 1 and DM 2 strains) was studied. Possible changes in outer membrane protein expression, permeability to cephaloridine, active efflux, and hydrolytic activity of beta-lactamase-crude extracts were evaluated under the influence of ciprofloxacin, sodium salicylate, and 2,4-dinitrophenol. Results were compared with those of the effect of the same three chemicals on a normally beta-lactamase-inducible wild-type C. freundii strain. The three assayed compounds decreased beta-lactamase hydrolysis on cephaloridine in both the two clinical isolates as well as in the wild-type strain. However, only the DM 1 and DM 2 strains showed increased susceptibility to beta-lactams. Sodium salicylate and 2,4-dinitrophenol, but not ciprofloxacin, reduced the expression of a 45-kDa outer membrane protein in the three studied strains, which was accompanied by a 4- to 20-fold diminution in permeability to cephaloridine. In conclusion, two mar RAB inducers and ciprofloxacin induced the Mar phenotype and repressed AmpC beta-lactamase synthesis in the DM 1 and DM 2 clinical isolates.

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2,4-DinitrophenolCiprofloxacinCitrobacter freundiiDrug Resistance, BacterialEnzyme InductionHumansSalicylatesbeta-Lactamasesbeta-LactamsJournal ArticleResearch Support, Non-U.S. Gov't

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María M Tavío, Mariagrazia Perilli, Jordi Vila, Pino Becerro, Joaquím Ruiz, Gianfranco Amicosante, María T Jiménez De Anta. 2005. Ciprofloxacin, salicylate, and 2,4-dinitrophenol decrease production of AmpC-type beta-lactamase in two Citrobacter freundii clinical isolates.. https://doi.org/10.1089/mdr.2005.11.225

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