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bioRxiv · 10.1101/663674

Genomic and phenotypic comparison of environmental and patient-derived isolates of Pseudomonas aeruginosa suggest that antimicrobial resistance is rare within the environment

Ramsay, K. A.·Wardell, S. J.·Patrick, W. M.·Brockway, B.·Reid, D. W.·Winstanley, C.·Bell, S. C.·Lamont, I. L.
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Abstract

Patient-derived isolates of the opportunistic pathogen Pseudomonas aeruginosa are frequently resistant to antibiotics due to the presence of sequence variants in resistance-associated genes. However, the frequency of antibiotic resistance and of resistance-associated sequence variants in environmental isolates of P. aeruginosa has not been well studied. Antimicrobial susceptibility testing (ciprofloxacin, ceftazidime, meropenem, tobramycin) of environmental (n=50) and cystic fibrosis (n=42) P. aeruginosa isolates was carried out. Following whole genome sequencing of all isolates, twenty-five resistance-associated genes were analysed for the presence of likely function-altering sequence variants. Environmental isolates were susceptible to all antibiotics with one exception, whereas patient-derived isolates had significant frequencies of resistance to each antibiotic and a greater number of likely resistance-associated genetic variants. These findings indicate that the natural environment does not act as a reservoir of antibiotic-resistant P. aeruginosa, supporting a model in which antibiotic susceptible environmental bacteria infect patients and develop resistance during infection.\n\nAuthor Contributions\n\nO_TBL View this table:\norg.highwire.dtl.DTLVardef@19d869eorg.highwire.dtl.DTLVardef@f10c9forg.highwire.dtl.DTLVardef@173a576org.highwire.dtl.DTLVardef@17415e8org.highwire.dtl.DTLVardef@4a5d25_HPS_FORMAT_FIGEXP M_TBL C_TBL

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Ramsay, K. A., Wardell, S. J., Patrick, W. M., Brockway, B., Reid, D. W., Winstanley, C., Bell, S. C., Lamont, I. L.. 2019-06-07. Genomic and phenotypic comparison of environmental and patient-derived isolates of Pseudomonas aeruginosa suggest that antimicrobial resistance is rare within the environment. https://doi.org/10.1101/663674

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