Do plastics serve as a possible vector for the spread of antibiotic resistance? First insights from bacteria associated to a polystyrene piece from King George Island (Antarctica).

The retrieval of a polystyrene macro-plastic piece stranded on the shores in King George Island (South Shetlands, Antarctica) gave the opportunity to explore the associated bacterial flora. A total of 27 bacterial isolates were identified by molecular 16s rRNA gene sequencing and 7 strains were selected and screened for their ability to produce biofilm and antibiotic susceptibility profiles. All the bacterial isolates were able to produce biofilm. The Kirby-Bauer disk diffusion susceptibility test to 34 antibiotics showed multiple antibiotic resistances against the molecules cefuroxime and cefazolin (belonging to cephalosporins), cinoxacin (belonging to quinolones) and ampicillin, amoxicillin + clavulanic acid, carbenicillin and mezlocillin (belonging to beta-lactams). The obtained results suggest that plastics can serve as vectors for the spread of multiple resistances to antibiotics across Antarctic marine environments and underline the relevance of future studies on this topic.