Download MendeleyA Structurally Characterized Staphylococcus aureus Evolutionary Escape Route from Treatment with the Antibiotic Linezolid.
Perlaza-Jimenez, L., Tan, K.S., Piper, S.J., Johnson, R.M., Bamert, R.S., Stubenrauch, C.J., Wright, A., Lupton, D., Lithgow, T., Belousoff, M.J.(2022) Microbiol Spectr 10: e0058322-e0058322
- PubMed: 35736238
- DOI: https://doi.org/10.1128/spectrum.00583-22
- Primary Citation of Related Structures:
7TTU, 7TTW - PubMed Abstract:
Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen that presents great health concerns. Treatment requires the use of last-line antibiotics, such as members of the oxazolidinone family, of which linezolid is the first member to see regular use in the clinic. Here, we report a short time scale selection experiment in which strains of MRSA were subjected to linezolid treatment. Clonal isolates which had evolved a linezolid-resistant phenotype were characterized by whole-genome sequencing. Linezolid-resistant mutants were identified which had accumulated mutations in the ribosomal protein uL3. Multiple clones which had two mutations in uL3 exhibited resistance to linezolid, 2-fold higher than the clinical breakpoint. Ribosomes from this strain were isolated and subjected to single-particle cryo-electron microscopic analysis and compared to the ribosomes from the parent strain. We found that the mutations in uL3 lead to a rearrangement of a loop that makes contact with Helix 90, propagating a structural change over 15 Å away. This distal change swings nucleotide U2504 into the binding site of the antibiotic, causing linezolid resistance. IMPORTANCE Antibiotic resistance poses a critical problem to human health and decreases the utility of these lifesaving drugs. Of particular concern is the "superbug" methicillin-resistant Staphylococcus aureus (MRSA), for which treatment of infection requires the use of last-line antibiotics, including linezolid. In this paper, we characterize the atomic rearrangements which the ribosome, the target of linezolid, undergoes during its evolutionary journey toward becoming drug resistant. Using cryo-electron microscopy, we describe a particular molecular mechanism which MRSA uses to become resistant to linezolid.
Organizational Affiliation:
Centre to Impact AMR, Monash Universitygrid.1002.3, Clayton, Victoria, Australia.
