Tolerance to multiple metal stressors in emerging non-typhoidal MDR Salmonella serotypes: a relevant role for copper in anaerobic conditions

• Type: Article in International Scientific Journal
• Date: 2016

Authors

J Mourão (Author) FFUP; Marçal, Sara (Author) Other; Ramos, Paula (Author) Other; Campos, Joana (Author) Other; Machado, Jorge (Author) Other; Luisa Peixe (Author) FFUP; Novais, Carla (Author) FFUP; Antunes, Patrícia (Author) FCNAUP

Journal

Title: Journal of Antimicrobial Chemotherapy

Vol. 71 No. 8

Pages: 2147-2157

ISSN: 0305-7453

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 32 Citations

Scopus - 31 Citations

Pubmed / Medline

Scientific classification

CORDIS: Health sciences

FOS: Medical and Health sciences

Other information

Authenticus ID: P-00M-0CS

DOI: 10.1093/jac/dkw120

Abstract (EN): Objectives: Factors driving the expansion of particular MDR Salmonella serotypes/clones are not completely understood. We assessed if emergent MDR Salmonella serotypes/clones were more enriched in metal tolerance genes (e.g. to Cu/Ag) than other less frequent ones, as an additional feature to survive in environments contaminated with metals. Methods: Metal (Cu pco/Ag,Cu sil/Hg mer/As ars/Te ter) tolerance genes screening (PCR/sequencing), MICs of CuSO4/AgNO3 (aerobiosis/anaerobiosis), genetic element characterization (S1/I-CeuI PFGE) and conjugation assays were performed in a well-characterized Salmonella collection (n¿275 isolates; 2000¿14; 49 serotypes/clones). Results: The sil+pco genes were detected in 37% of isolates from diverse serotypes, mainly in emergent Rissen/ST469 and Typhimurium/ST34 European clone (100%), which are mostly associated with pig settings where Cu is highly used. These genes were frequently co-located with merA+terFand/or antibiotic resistance genes in plasmids (100¿270 kb; IncHI2/IncHI1/IncN/IncFIIA; mostly transferable by conjugation) or in the chromosome. Most sil+pco+ isolates (77%) were MDR contrasting with sil+pco2 ones (48%). The sil+pco+ isolates presented significantly higher MICCuSO4 under anaerobiosis (MIC50/MIC90¿28/32 mM) and MICAgNO3 after previous Ag contact (MIC50/MIC90.3 mM) than sil2 ones (MIC50/MIC90¿2/8 mM to CuSO4; MIC50/MIC90¿0.125/0.16 mM to AgNO3). Use of these modified methodological approaches allowed the establishment of CuSO4/AgNO3 tolerance cut-offs to differentiate sil+ and sil2 isolates, here firstly proposed. Conclusions: This study demonstrates that acquisition of Cu/Ag tolerance genes (sil/pco genes) might contribute to the emergence of particular clinically relevant MDR Salmonella serotypes/clones by facilitating their survival in diverse metal-contaminated settings, particularly in pig production. Assessment of control measures for the use and/or accumulation of metals in diverse environments are needed to prevent a wider expansion of such strains or the emergence of new ones.

Language: English

Type (Professor's evaluation): Scientific

Notes: <a href="http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS&DestLinkType=FullRecord&KeyUT=000383249500016">Indexado na ISI Web of Science</a> <a href="https://www.ncbi.nlm.nih.gov/pubmed/27118781">Indexado na Pubmed</a> <a href="http://www.scopus.com/record/display.url?eid=2-s2.0-84977576839&origin=inward">Indexado na Scopus</a>

No. of pages: 11