Integrated metagenomic and culture-dependent profiling reveals electric shavers as selective reservoirs for multidrug-resistant opportunistic pathogens

<h4>Introduction</h4>Personal care items are commonly viewed as passive vehicles for microbial transfer; however, the physicochemical stresses they impose may actively shape microbial persistence, community composition, and the distribution of resistance-associated determinants. Electric shavers may therefore constitute an underrecognized anthropogenic niche for the enrichment of clinically relevant antimicrobial resistance traits.<h4>Methods</h4>We sampled electric shavers from 10 individuals at early (day 2) and mature (day 21) usage stages, generating 8 high-quality metagenomes and recovering 97 viable isolates spanning 16 bacterial species. Deep metagenomic sequencing, combined with whole-genome sequencing of 45 representative isolates, was used to resolve the ecological, functional, and evolutionary features of shaver-associated microbiomes.<h4>Results</h4>Shaver-associated community assembly was dominated by stringent environmental filtering, which promoted the repeated enrichment of stress-adapted lineages across hosts, notably <i>Acinetobacter ursingii</i> MLST3244 and <i>Klebsiella pneumoniae</i> MLST995 and MLST23. We further identified recurrent mobile genetic element-associated resistance islands and plasmid backbones in different host cohorts, suggesting repeated selection under shared anthropogenic pressures rather than direct evidence of <i>de novo</i> convergent evolution. Importantly, viable <i>Klebsiella pneumoniae</i> isolates co-carried extended-spectrum β-lactamase genes such as <i>bla</i> _SHV and major virulence determinants, while metagenomic profiling detected reads assigned to <i>mcr-</i> and <i>tet</i>(X)-like gene variants at the community level, targeted PCR further confirmed the presence of these resistance determinants.<h4>Discussion</h4>Because routine shaving can generate barrier-disrupting micro-abrasions, electric shavers may function as selective reservoirs for multidrug-resistant bacteria. Our findings reveal a previously overlooked exposure interface through which everyday personal care practices may promote the enrichment and persistence of clinically important resistance and virulence determinants.