RNA polymerase mutations cause cephalosporin resistance in clinical Neisseria gonorrhoeae isolates
- Harvard TH Chan School of Public Health, United States
- Harvard Medical School, United States
- Royal Sussex County Hospital, United Kingdom
- University of Oxford, United Kingdom
Abstract
Increasing Neisseria gonorrhoeae resistance to ceftriaxone, the last antibiotic recommended for empiric gonorrhea treatment, poses an urgent public health threat. However, the genetic basis of reduced susceptibility to ceftriaxone is not completely understood: while most ceftriaxone resistance in clinical isolates is caused by target site mutations in penA, others lack these mutations. We show that penA-independent ceftriaxone resistance has evolved multiple times through distinct mutations in rpoB and rpoD. We identify five mutations in these genes that each increase resistance to ceftriaxone, including one mutation that arose independently in two lineages, and show that clinical isolates from multiple lineages are a single nucleotide change from ceftriaxone resistance. These RNA polymerase mutations result in large-scale transcriptional changes without altering susceptibility to other antibiotics, reducing growth rate, or deranging cell morphology. These results underscore the unexpected diversity of pathways to resistance and the importance of continued surveillance for novel resistance mutations.
Data availability
Sequencing data have been deposited in the NCBI SRA database under accession number PRJNA540288.
Article and author information
Author details
Funding
Richard and Susan Smith Family Foundation
- Yonatan H Grad
National Institutes of Health (R01 AI132606)
- Yonatan H Grad
National Institutes of Health (R01 GM76710)
- Suzanne Walker
National Institutes of Health (F32 GM123579)
- Michael A Welsh
National Institutes of Health (T32 GM007753)
- Daniel H F Rubin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Palace 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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RNA polymerase mutations cause cephalosporin resistance in clinical Neisseria gonorrhoeae isolates
eLife 9:e51407.
https://doi.org/10.7554/eLife.51407
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