Study predicts streptomycin resistance mutations are widespread and easily evolved across bacterial species
A computational study screened over 20,000 bacterial genomes and found that most bacterial species can readily evolve resistance to streptomycin, while roughly 7% already carry resistance variants. Researchers curated 12 high-confidence resistance mutations across two genes — rpsL and rrs — and assessed both the ease of acquiring resistance and its pre-existing presence. The findings suggest streptomycin resistance is far more broadly distributed across the bacterial tree of life than previously recognized, with implications for antibiotic treatment strategies.
Researchers posting to bioRxiv used computational methods to evaluate streptomycin resistance potential across the bacterial tree of life, analyzing more than 20,000 genomes from diverse bacterial clades. The study focused on 12 curated high-confidence resistance mutations — eight in the rpsL gene and four in the rrs gene — examining both 'evolvability' (how accessible resistance mutations are via single-nucleotide changes) and 'intrinsic resistance' (whether resistance variants are already present). Results indicate that the majority of bacterial species have genetic pathways that make rpsL resistance mutations readily achievable. Approximately 7% of bacterial species were found to already harbor rpsL resistance variants, with a notably uneven taxonomic distribution and a particular enrichment within the Alphaproteobacteria class. The study provides what the authors describe as a global map of the streptomycin resistance mutational landscape, offering testable predictions for experimental follow-up. Because streptomycin is used to treat serious infections including tuberculosis and plague, understanding the breadth of potential resistance is clinically relevant. The work also highlights that antimicrobial resistance research has historically been concentrated on a narrow set of pathogens and model organisms, leaving most of bacterial diversity understudied.
What's missing
As a preprint, this study has not yet undergone peer review, so findings should be treated as preliminary. The study is purely computational and does not include experimental validation confirming that predicted evolvable mutations actually confer phenotypic resistance in the species analyzed. The panel of 12 mutations may not capture the full diversity of streptomycin resistance mechanisms. It is also unclear whether intrinsically resistant species have been exposed to streptomycin in their natural environments, which would affect interpretation of the 7% prevalence figure.
What different sources said
- bioRxivCenter
Mutations associated with streptomycin resistance predicted to be highly prevalent and evolvable across bacteria
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