Multiple adaptive routes of Salmonella enterica Typhimurium to biocide and antibiotic exposure

BMC Genomics

Research Article

Emmanuela Marchi¹  Carlo Viti¹  Denis Grandgirard²  Stephen L. Leib²  Ricardo León-Sampedro³  Tânia Curiao³  Teresa M. Coque⁴  Fernando Baquero⁴  José Luis Martinez⁵  Marco R. Oggioni⁶ 

[1] Department of Agrifood Production and Environmental Sciences, University of Florence, Firenze, Italy;Neuroinfection Laboratory, Institute for Infectious Diseases, Bern, Switzerland;Servicio de Microbiología, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain;CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain;Servicio de Microbiología, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain;CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain;Unidad de Resistencia a Antibióticos y Virulencia bacteriana asociada al Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain;Unidad de Resistencia a Antibióticos y Virulencia bacteriana asociada al Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain;Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CSIC), Darwin 3, 28049, Cantoblanco, Madrid, Spain;University of Leicester, Leicester, UK;

关键词: Biocide resistance;    Antimicrobial susceptibility;    WGS;    Transcriptomics;    Collateral sensitivity;   

DOI  :  10.1186/s12864-016-2778-z

 received in 2015-10-16, accepted in 2016-05-26,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundBiocides and antibiotics are used to eradicate or prevent the growth of microbial species on surfaces (occasionally on catheters), or infected sites, either in combination or sequentially, raising concerns about the development of co-resistance to both antimicrobial types. The effect of such compounds on Salmonella enterica, a major food-borne and zoonotic pathogen, has been analysed in different studies, but only few works evaluated its biological cost, and the overall effects at the genomic and transcriptomic levels associated with diverse phenotypes resulting from biocide exposure, which was the aim of this work.ResultsExposure to triclosan, clorhexidine, benzalkonium, (but not to hypochlorite) resulted in mutants with different phenotypes to a wide range of antimicrobials even unrelated to the selective agent. Most biocide-resistant mutants showed increased susceptibility to compounds acting on the cell wall (β-lactams) or the cell membranes (poly-L-lysine, polymyxin B, colistin or toxic anions). Mutations (SNPs) were found in three intergenic regions and nine genes, which have a role in energy production, amino acids, carbohydrates or lipids metabolism, some of them involved in membrane transport and pathogenicity. Comparative transcriptomics of biocide-resistant mutants showed over-expression of genes encoding efflux pumps (sugE), ribosomal and transcription-related proteins, cold-shock response (cpeE) and enzymes of microaerobic metabolism including those of the phosphotransferase system. Mainly ribosomal, metabolic and pathogenicity-related genes had affected expression in both in vitro-selected biocide mutants and field Salmonella isolates with reduced biocide susceptibility.ConclusionsMultiple pathways can be involved in the adaptation of Salmonella to biocides, mainly related with global stress, or involving metabolic and membrane alterations, and eventually causing “collateral sensitivity” to other antimicrobials. These changes might impact the bacterial-environment interaction, imposing significant bacterial fitness costs which may reduce the chances of fixation and spread of biocide resistant mutants.

【 授权许可】

CC BY   
© The Author(s). 2016