title: Characteristics of extended-spectrum β-lactamase (ESBL)- and pAmpC beta-lactamase-producing Enterobacteriaceae of water samples in Tunisia.
abstract: The presence of extended-spectrum beta-lactamase and plasmid-mediated AmpC beta-lactamase producing Enterobacteriaceae (ESBL-Eb and pAmpC-Eb, respectively) was analyzed in 57 wastewater and 57 surface-water samples in Tunisia. Twenty-four of the 57 wastewater samples (42.1%) and one of the 57 surface-water samples (1.7%, a river that received effluents of a wastewater-treatment-plant) contained ESBL-Eb or pAmpC-Eb; one ESBL/pAmpC-Eb per positive sample was further characterized. Beta-lactamase genes detected were as follows: blaCTX-M-1 (10 Escherichia coli),blaCTX-M-15 (eight E. coli, one Klebsiella pneumoniae, one Citrobacter freundii), blaCTX-M-14 (one E. coli) and blaCMY-2 (four E. coli). The blaTEM-1, blaOXA-1 or blaSHV-1 genes were also found in 72% of these isolates. The ISEcp1, orf477 or IS903 sequences were found upstream or downstream of blaCTX-M genes. Class 1 integrons were present in 16 of the 25 ESBL-Eb/pAmpC-Eb strains (64%), and contained five different gene-cassette arrays. Most of the strains (76%) showed a multiresistant phenotype and qnr genes were identified in four strains. Molecular typing of ESBL/CMY-2-producing E. coli isolates showed 23 different PFGE-patterns and 15 different sequence-types (ST10, ST46, ST48, ST58, ST69, ST101, ST117, ST131, ST141, ST288, ST359, ST399, ST405, ST617, and the new ST4530); these strains were ascribed to phylogroups A (11 isolates), B1 (3 isolates), D (6 isolates) and B2 (3 isolates). From one to five plasmids were detected in each strain (size from 30kb to >240kb) and ESBL or pAmpC genes were transferred by conjugation in 69.5% of the E. coli strains. In conclusion, ESBL-Eb and pAmpC-Eb strains are frequently detected in wastewater samples and they might be a source for dissemination in other environments with repercussion in public health.
authors.affiliation: Laboratoire des Microorganismes et Biomolécules actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Leila
authors.initials: L
authors.lastname: Ben Said
authors.affiliation: Laboratory of Epidemiology and Veterinary Microbiology, Pasteur Institute of Tunis, Tunisia.
authors.forename: Ahlem
authors.initials: A
authors.lastname: Jouini
authors.affiliation: Area de Bioquímica y Biología Molecular, Universidad de La Rioja, 26006 Logroño, Spain.
authors.forename: Carla Andrea
authors.initials: CA
authors.lastname: Alonso
authors.affiliation: Laboratoire des Microorganismes et Biomolécules actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Naouel
authors.initials: N
authors.lastname: Klibi
authors.affiliation: Laboratoire des Microorganismes et Biomolécules actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Raoudha
authors.initials: R
authors.lastname: Dziri
authors.affiliation: Laboratoire des Microorganismes et Biomolécules actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Abdellatif
authors.initials: A
authors.lastname: Boudabous
authors.affiliation: Laboratoire des Microorganismes et Biomolécules actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia; Institut Supérieur des Sciences Biologiques Appliquées de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Karim
authors.initials: K
authors.lastname: Ben Slama
authors.affiliation: Area de Bioquímica y Biología Molecular, Universidad de La Rioja, 26006 Logroño, Spain. Electronic address: carmen.torres@unirioja.es.
authors.forename: Carmen
authors.initials: C
authors.lastname: Torres
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D004784:Environmental Monitoring; D005798:Genes, Bacterial; D014416:Tunisia; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis*; D001618:beta-Lactamases / Q000032:analysis / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D014874:Water Pollutants, Chemical; C048795:AmpC beta-lactamases; D001618:beta-Lactamases
keywords: CTX-M; ESBL; Tunisia; Wastewater; pAmpC