Emergence of plasmid-mediated fosfomycin resistance among Escherichia coli harboring fosA4 , tet (X4), and mcr-1 genes in wild birds

• DOI: 10.1128/msystems.01673-24
• Publication Date: 2025-03-13T13:00:37Z
• Authors: Asim Munir; Xiaoyu Lu; Farwa Humak; Cemil Kürekci; Muhammad Shahid M...; Sehrish Gul; Zhiqiang Wang; Mashkoor Mohsin; Ruichao Li
• Keywords: Fosfomycin; Colistin; MCR-1; Tigecycline

ABSTRACT Fosfomycin represents a last-line reserve antibiotic for the treatment of infections caused by multidrug-resistant (MDR) bacteria. Nevertheless, advent plasmid-mediated fosfomycin resistance among bacteria from humans and food animals incurs great concern. This study reports detection genomic portrait gene, fosA4 , amid Escherichia coli wild birds co-harboring tigecycline gene tet (X4), colistin mcr-1 . A total 100 samples fecal droppings in urban parks Faisalabad, Pakistan were subjected isolation characterization fosfomycin-resistant E. The was identified 11 (11%) isolates, all exhibited an MDR phenotype. Genome sequencing confirmed that -positive isolates also co-harbored mobile (X4) on large IncFII plasmid. One isolate PKF8 belonging to ST48 co-carried IncHI2 To extent our knowledge, this is first discovery genes. emergence these pivotal antimicrobial genes native South Asia with their close association alarming. Our findings highlight urgent need further surveillance bacterial last-resort antibiotics clinics, animal farming, environment Health approach. IMPORTANCE global spread bearing strains public health However, research focusing pervasiveness still rare, best documentation highlighting concurrent presence within recovered Pakistan. co-existence ARGs along phylogenetic analysis revealed plasmids carried have ability horizontally between birds, animals, humans. Co-existence -carrying worrying warrants investigation.