title: Antibiotic resistant Pseudomonas spp. in the aquatic environment: A prevalence study under tropical and temperate climate conditions.
abstract: Microbial populations which are resistant to antibiotics are an emerging environmental concern with potentially serious implications for public health. Thus, there is a growing concern in exploring the occurrence of antibiotic resistance in the environment with no limitations to the factors that contribute to their emergence. The aquatic environment is considered to be a hot-spot for the acquisition and spread of antibiotic resistance due to pollution with emerging contaminants derived from anthropogenic activities. In this study, we report on the isolation and characterization of 141 Pseudomonas spp. from aquatic sediments receiving partially (un)treated hospital and communal effluents from three distinct geographical locations: Democratic Republic of the Congo (DRC), India (IN), and Switzerland (CH). P. putida (42%) and P. aeruginosa (39%) were the dominant Pseudomonas species. The highest frequency of antibiotic resistance against eight anti-pseudomonas agents was found among IN isolates (35-60%), followed by DRC (18-50%) and CH (12-54%). CTX-M was the most frequent β-lactamase found in CH (47% of isolates), while VIM-1 was dominant in isolates from DRC (61%) and IN (29%). NDM-1 was found in 29% of the total IN isolates and surprisingly also in 6% of CH isolates. Chromosomally-encoded efflux mechanisms were overexpressed in P. aeruginosa isolates from all three geographic locations. In vitro conjugative transfers of antibiotic resistance plasmids occurred more frequently under tropical temperatures (30 and 37 °C) than under temperate conditions (10 °C). The presence of Extended Spectrum β-lactamases (ESBLs) and Metallo β-lactamases (MBLs) in the isolates from environmental samples has important implications for humans who depend on public water supply and sanitation facilities. To our knowledge, this is the first study to demonstrate a comparison between treated/untreated effluents from urban and hospital settings as a source of microbial resistance by evaluating the aquatic ecosystems sediments from tropical and temperate climate conditions. Taken together, our findings demonstrate a widespread occurrence of antibiotic resistance in aquatic ecosystems sediments receiving untreated/treated wastewater and how these contemporary sources of contamination, contribute to the spread of microbial resistance in the aquatic environment. This research presents also useful tools to evaluate sediment quality in the receiving river/reservoir systems which can be applied to similar environments.
authors.affiliation: University of Geneva, Faculty of Sciences, Section of Earth and Environmental Science, Department F.-A. Forel for Environmental and Aquatic Sciences and Institute of Environmental Sciences, Blvd Carl-Vogt 66, CH-1205 Geneva, Switzerland.
authors.forename: Naresh
authors.initials: N
authors.lastname: Devarajan
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva, 1, rue Michel Servet, CH-1211 Geneva 4, Switzerland; Transplant Infectious Diseases Unit, University Hospitals Geneva, 4, rue Gabrielle-Perret-Gentil, CH-1211 Geneva 14, Switzerland.
authors.forename: Thilo
authors.initials: T
authors.lastname: Köhler
authors.affiliation: University of Geneva, Faculty of Sciences, Section of Earth and Environmental Science, Department F.-A. Forel for Environmental and Aquatic Sciences and Institute of Environmental Sciences, Blvd Carl-Vogt 66, CH-1205 Geneva, Switzerland.
authors.forename: Periyasamy
authors.initials: P
authors.lastname: Sivalingam
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva, 1, rue Michel Servet, CH-1211 Geneva 4, Switzerland; Transplant Infectious Diseases Unit, University Hospitals Geneva, 4, rue Gabrielle-Perret-Gentil, CH-1211 Geneva 14, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: van Delden
authors.affiliation: University of Kinshasa (UNIKIN), Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, Democratic Republic of the Congo.
authors.forename: Crispin K
authors.initials: CK
authors.lastname: Mulaji
authors.affiliation: University of Kinshasa (UNIKIN), Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, Democratic Republic of the Congo.
authors.forename: Pius T
authors.initials: PT
authors.lastname: Mpiana
authors.affiliation: University of Geneva, Faculty of Sciences, Section of Earth and Environmental Science, Department F.-A. Forel for Environmental and Aquatic Sciences and Institute of Environmental Sciences, Blvd Carl-Vogt 66, CH-1205 Geneva, Switzerland.
authors.forename: Bastiaan W
authors.initials: BW
authors.lastname: Ibelings
authors.affiliation: University of Geneva, Faculty of Sciences, Section of Earth and Environmental Science, Department F.-A. Forel for Environmental and Aquatic Sciences and Institute of Environmental Sciences, Blvd Carl-Vogt 66, CH-1205 Geneva, Switzerland; University of Kinshasa (UNIKIN), Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, Democratic Republic of the Congo. Electronic address: john.pote@unige.ch.
authors.forename: John
authors.initials: J
authors.lastname: Poté
mesh_terms: D000900:Anti-Bacterial Agents; D002980:Climate; D003430:Cross-Sectional Studies; D008826:Microbial Sensitivity Tests; D011549:Pseudomonas; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D001618:beta-Lactamases
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: Antibiotic resistance; Aquatic environment contamination; Climatic condition; Extended spectrum β-lactamases; Pseudomonas species; Urban wastewater