title: Antibiotic and metal resistance among hospital and outdoor strains of Pseudomonas aeruginosa.
abstract: Phenotypic analyses of antibiotic and metal resistance of a collection of 130 strains of Pseudomonas aeruginosa from various outdoor (i.e. soil, water, animals) and hospital (environment, patients, individuals with cystic fibrosis) settings were performed. Resistance was scored according to the origin of the strains and their likely exposure to antibiotics and chemicals. Most of the 76 outdoor strains showed a wild-type antibiotic resistance phenotype, i.e. resistance to minocycline and trimethoprim-sulfamethoxazole. Sixty percent of hospital strains showed a multiresistance phenotype (from 3 to 16 antibiotics) and confirmed that frequent exposure to antibiotics favored selection and maintenance of antibiotic resistance in P. aeruginosa. Twelve percent of outdoor strains naturally exposed to antiseptics and hydrocarbons showed significant resistance profiles, suggesting that chemical contaminants could contribute to selection of antibiotic resistance. For metal resistance, outdoor strains were more frequently resistant to zinc and cadmium, whereas hospital strains were more frequently resistant to mercury and copper. Differences in metal resistance between the 130 strains investigated were not related to previously characterized processes such as those implicating czcA, involved in cadmium, zinc, and cobalt resistance, or copA and copB, involved in copper resistance. Regulatory or new processes were likely to have contributed to the observed variations. Strains showing strong resistance to antibiotics were the least resistant to metals, and inversely. The lack of significant correlations between antibiotic and metal resistance suggests involvement of distinct processes that are rarely co-selected. The effects of the P. aeruginosa collection size and multi-factorial selective pressure on data sets are discussed.
authors: Université de Lyon, France Research Group on Bacterial Opportunistic Pathogens and Environment, UMR 5557 Ecologie Microbienne, CNRS, VetAgro Sup and Université Lyon 1, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne Cedex, France. aderedjian@club-internet.fr
authors: Amélie
authors: A
authors: Deredjian
authors: Céline
authors: C
authors: Colinon
authors: Elisabeth
authors: E
authors: Brothier
authors: Sabine
authors: S
authors: Favre-Bonté
authors: Benoit
authors: B
authors: Cournoyer
authors: Sylvie
authors: S
authors: Nazaret
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003428:Cross Infection / Q000382:microbiology*; D003550:Cystic Fibrosis / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D004783:Environmental Microbiology; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D008670:Metals / Q000494:pharmacology*; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D008670:Metals