Genetic determinants facilitating the evolution of resistance to carbapenem antibiotics
- The Broad Institute of MIT and Harvard, United States
Abstract
In this era of rising antibiotic resistance, in contrast to our increasing understanding of mechanisms that cause resistance, our understanding of mechanisms that influence the propensity to evolve resistance remains limited. Here, we identified genetic factors that facilitate the evolution of resistance to carbapenems, the antibiotic of 'last resort,' in Klebsiella pneumoniae, the major carbapenem resistant species. In clinical isolates, we found that high-level transposon insertional mutagenesis plays an important role in contributing to high-level resistance frequencies in several major and emerging carbapenem-resistant lineages. A broader spectrum of resistance-conferring mutations for select carbapenems such as ertapenem also enables higher resistance frequencies and importantly, creates stepping-stones to achieve high-level resistance to all carbapenems. These mutational mechanisms can contribute to the evolution of resistance, in conjunction with the loss of systems that restrict horizontal resistance gene uptake, such as the CRISPR-Cas system. Given the need for greater antibiotic stewardship, these findings argue that in addition to considering the current efficacy of an antibiotic for a clinical isolate in antibiotic selection, considerations of future efficacy are also important. The genetic background of a clinical isolate and the exact antibiotic identity can and should also be considered as it is a determinant of a strain's propensity to become resistant. Together, these findings thus provide a molecular framework for understanding acquisition of carbapenem resistance in K. pneumoniae with important implications for diagnosing and treating this important class of pathogens.
Data availability
All data generated or analyzed during this study are included in this article and in the supplementary tables. Sequencing data is deposited to NCBI under the accession number PRJNA670748.
Article and author information
Author details
Roby P Bhattacharyya
Funding
National Institute of Allergy and Infectious Diseases (5R01AI117043-05)
- Deborah Hung
National Institute of Allergy and Infectious Diseases (U19AI110818)
- Ashlee M Earl
Anita and Josh Bekenstein Gram Negative Gift
- Deborah Hung
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Ma et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Genetic determinants facilitating the evolution of resistance to carbapenem antibiotics
eLife 10:e67310.
https://doi.org/10.7554/eLife.67310
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