The Fildes Peninsula is among the Antarctic regions most affected by human activity.As the interface between terrestrial and marine ecosystems,the intertidal is a gateway for ecological and public health risks.Antibio...The Fildes Peninsula is among the Antarctic regions most affected by human activity.As the interface between terrestrial and marine ecosystems,the intertidal is a gateway for ecological and public health risks.Antibiotic resistance genes(ARGs)and virulence factor genes(VFGs)intensify these risks by transferring pathogenic traits via horizontal gene transfer.However,a comprehensive assessment of ARGs and VFGs in Fildes Peninsula intertidal sediments is lacking.We addressed this gap by performing shotgun metagenomic sequencing on 14 intertidal sediments.We detected 20 ARG types comprising 397 subtypes.Multidrug,bacitracin,and polymyxin resistance dominated the resistome,although their overall abundance was relatively low.A total of 4,204 VFGs were identified and were primarily associated with adherence,motility,immune modulation,and effector delivery.The abundance of VFGs was also relatively low and significantly correlated with the abundance of ARGs.Additionally,we also identified 787 mobile genetic elements(MGEs)that carried 138 VFGs but found no ARGs associated with MGEs at the contig level.Host assignment implicated taxa such as Ilumatobacter as major ARG carriers and detected opportunistic pathogen Pseudomonas aeruginosa carrying CAM-1,a metallo-β-lactamase gene.In summary,our results reveal a highly diverse but generally low-abundance resistome and virulome in Fildes Peninsula intertidal sediments,with limited evidence for MGE-mediated ARG dissemination.However,they emphasize the necessity of monitoring to protect Antarctic microbial integrity.展开更多
基金supported by the Shanghai Frontiers Science Center of Polar Science(Grant no.SOO2024-04)the National Natural Science Foundation of China(Grant no.42476264)Lanzhou University(Grant no.lzuibky-2024-oy01).
文摘The Fildes Peninsula is among the Antarctic regions most affected by human activity.As the interface between terrestrial and marine ecosystems,the intertidal is a gateway for ecological and public health risks.Antibiotic resistance genes(ARGs)and virulence factor genes(VFGs)intensify these risks by transferring pathogenic traits via horizontal gene transfer.However,a comprehensive assessment of ARGs and VFGs in Fildes Peninsula intertidal sediments is lacking.We addressed this gap by performing shotgun metagenomic sequencing on 14 intertidal sediments.We detected 20 ARG types comprising 397 subtypes.Multidrug,bacitracin,and polymyxin resistance dominated the resistome,although their overall abundance was relatively low.A total of 4,204 VFGs were identified and were primarily associated with adherence,motility,immune modulation,and effector delivery.The abundance of VFGs was also relatively low and significantly correlated with the abundance of ARGs.Additionally,we also identified 787 mobile genetic elements(MGEs)that carried 138 VFGs but found no ARGs associated with MGEs at the contig level.Host assignment implicated taxa such as Ilumatobacter as major ARG carriers and detected opportunistic pathogen Pseudomonas aeruginosa carrying CAM-1,a metallo-β-lactamase gene.In summary,our results reveal a highly diverse but generally low-abundance resistome and virulome in Fildes Peninsula intertidal sediments,with limited evidence for MGE-mediated ARG dissemination.However,they emphasize the necessity of monitoring to protect Antarctic microbial integrity.
