Evolution of antibiotic resistance at low antibiotic concentrations including selection below the minimal selective concentration

TY - JOUR

T1 - Evolution of antibiotic resistance at low antibiotic concentrations including selection below the minimal selective concentration

AU - Stanton, Isobel C.

AU - Murray, Aimee K.

AU - Zhang, Lihong

AU - Snape, Jason

AU - Gaze, William H.

N1 - Publisher Copyright: © 2020, The Author(s).

PY - 2020/9/3

Y1 - 2020/9/3

N2 - Determining the selective potential of antibiotics at environmental concentrations is critical for designing effective strategies to limit selection for antibiotic resistance. This study determined the minimal selective concentrations (MSCs) for macrolide and fluoroquinolone antibiotics included on the European Commissionʼs Water Framework Directive’s priority hazardous substances Watch List. The macrolides demonstrated positive selection for ermF at concentrations 1–2 orders of magnitude greater (>500 and <750 µg/L) than measured environmental concentrations (MECs). Ciprofloxacin illustrated positive selection for intI1 at concentrations similar to current MECs (>7.8 and <15.6 µg/L). This highlights the need for compound specific assessment of selective potential. In addition, a sub-MSC selective window defined by the minimal increased persistence concentration (MIPC) is described. Differential rates of negative selection (or persistence) were associated with elevated prevalence relative to the no antibiotic control below the MSC. This increased persistence leads to opportunities for further selection over time and risk of human exposure and environmental transmission.

AB - Determining the selective potential of antibiotics at environmental concentrations is critical for designing effective strategies to limit selection for antibiotic resistance. This study determined the minimal selective concentrations (MSCs) for macrolide and fluoroquinolone antibiotics included on the European Commissionʼs Water Framework Directive’s priority hazardous substances Watch List. The macrolides demonstrated positive selection for ermF at concentrations 1–2 orders of magnitude greater (>500 and <750 µg/L) than measured environmental concentrations (MECs). Ciprofloxacin illustrated positive selection for intI1 at concentrations similar to current MECs (>7.8 and <15.6 µg/L). This highlights the need for compound specific assessment of selective potential. In addition, a sub-MSC selective window defined by the minimal increased persistence concentration (MIPC) is described. Differential rates of negative selection (or persistence) were associated with elevated prevalence relative to the no antibiotic control below the MSC. This increased persistence leads to opportunities for further selection over time and risk of human exposure and environmental transmission.

UR - http://www.scopus.com/inward/record.url?scp=85090116109&partnerID=8YFLogxK

U2 - 10.1038/s42003-020-01176-w

DO - 10.1038/s42003-020-01176-w

M3 - Article

C2 - 32884065

AN - SCOPUS:85090116109

SN - 2399-3642

VL - 3

JO - Communications Biology

JF - Communications Biology

IS - 1

M1 - 467

ER -