Bacterial resistance evolution towards disinfectants and antimicrobial surfaces and development of a standardized test
- Question
Disinfectants and antimicrobial surfaces (AMCs) are important tools to prevent the spread of pathogens and antimicrobial resistant bacteria. However, concerns have been raised about the possibility for the evolution and selection of resistance against disinfectants and AMCs. In turn, resistance against disinfectants and AMCs can be associated to antibiotic resistance due to cross-resistance - a single mechanism conferring resistance to a disinfectant and an antibiotic- and co-resistance - two distinct mechanisms physically linked on e.g. a plasmid. The risk for resistance and cross-resistance during use of biocides (including disinfectants and AMCs) must be evaluated during authorization according to the EU biocidal product regulation. However, to date there is a lack of standardized methods that support risk assessment during the authorization process.
Methods
We used adaptive laboratory evolution (ALE) experiments which are based on repeated exposure of bacteria toQuestion
Disinfectants and antimicrobial surfaces (AMCs) are important tools to prevent the spread of pathogens and antimicrobial resistant bacteria. However, concerns have been raised about the possibility for the evolution and selection of resistance against disinfectants and AMCs. In turn, resistance against disinfectants and AMCs can be associated to antibiotic resistance due to cross-resistance - a single mechanism conferring resistance to a disinfectant and an antibiotic- and co-resistance - two distinct mechanisms physically linked on e.g. a plasmid. The risk for resistance and cross-resistance during use of biocides (including disinfectants and AMCs) must be evaluated during authorization according to the EU biocidal product regulation. However, to date there is a lack of standardized methods that support risk assessment during the authorization process.
Methods
We used adaptive laboratory evolution (ALE) experiments which are based on repeated exposure of bacteria to disinfectants or AMCs. The experiments are followed by phenotypic (antimicrobial susceptibility testing) and genotypic (whole genome sequencing) characterization of the evolved strains. The basic idea of these experiments is to expose bacteria to lethal conditions and select for mutants with increased survival. This approach is fundamentally different to other ALE experiments, which commonly select for increased growth at subinhibitory concentrations. However, selection for increased survival represents a selective pressure that more realistically reflects selection under in-use conditions of disinfectants and AMCs.
Results
First, we studied adaptation of E. coli during repeated disinfection with benzalkonium chloride in a suspension assay. The experiments showed a 2000-fold increase in survival within 5 exposure cycles. The adaptive changes are linked to highly parallel mutations in genes related to lipid A biosynthesis, less negative cell surface charge, reduced growth rate and increased competitive ability in the presence of certain antibiotics. We use the same approach to develop standardizable ALE experiments based upon accepted standards that are used to determine the efficacy of disinfectants (EN 13697) and antimicrobial surfaces (ISO 22196). The results highlight pronounced adaptation of different test strains towards surface disinfection (benzalkonium chloride and isopropanol) and AMCs (copper).
Conclusion
Bacteria can adapt with increased survival towards lethal stress imposed by disinfectants and AMCs. The adaptive ability of bacteria to disinfectants and AMCs can be determined in a standardized manner.…
Autor*innen: | Selina SchmidtORCiD |
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Weitere Person: | Frank SchreiberORCiD, Viola Boenke, Niclas NordholtORCiD, Orestis Kanaris, Claudia Sündermann |
Dokumenttyp: | Posterpräsentation |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2022 |
Organisationseinheit der BAM: | 4 Material und Umwelt |
4 Material und Umwelt / 4.1 Biologische Materialschädigung und Referenzorganismen | |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Sanitär- und Kommunaltechnik; Umwelttechnik |
Freie Schlagwörter: | Antimicrobial resistance; Antimicrobial surfaces; ISO22196; Round robin test |
Themenfelder/Aktivitätsfelder der BAM: | Umwelt |
Umwelt / Umwelt-Material-Interaktionen | |
Veranstaltung: | 74. Jahrestagung der Deutschen Gesellschaft für Hygiene und Mikrobiologie [DGHM] e. V. |
Veranstaltungsort: | Berlin, Germany |
Beginndatum der Veranstaltung: | 05.09.2022 |
Enddatum der Veranstaltung: | 07.09.2022 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 30.11.2022 |
Referierte Publikation: | Nein |