Prevalence of fosA3 Gene in Fosfomycin-Resistant Proteus mirabilis in the Autonomous Community of Madrid (Spain) and Characterization of Two Positive Strains

Microb Drug Resist. 2023 Oct;29(10):444-447. doi: 10.1089/mdr.2022.0269. Epub 2023 Apr 6.

Abstract

Plasmid-mediated resistance to fosfomycin has been seldom described in Proteus mirabilis. We report two strains harboring fosA3 gene. Whole-genome sequencing revealed a plasmid that encoded fosA3 gene flanked by two insertion sequence (IS)26 mobile elements. Both strains also produced the blaCTX-M-65 gene that was located in the same plasmid. The sequence detected was IS1182-blaCTX-M-65-orf1-orf2-IS26-IS26-fosA3-orf1-orf2-orf3-IS26. The importance of this transposon lies in its ability to spread in Enterobacterales, therefore, epidemiological surveillance should be carried out.

Keywords: antibiotic resistance; fosA3 Proteus mirabilis; fosfomycin; urinary tract infection.