School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China.
Environ Sci Technol. 2021 Nov 16;55(22):15136-15148. doi: 10.1021/acs.est.1c03444. Epub 2021 Nov 5.
Knowledge of the distribution and dissemination of antibiotic resistance genes (ARGs) is essential for understanding anthropogenic impacts on natural ecosystems. The transportation of ARGs via aquatic environments is significant and has received great attention, but whether there has been anthropogenic ARG pollution to the hadal ocean ecosystem has not been well explored. For investigating ecological health concerns, we profiled the ARG occurrence in sediments of the Mariana Trench (MT) (10 890 m), the deepest region of the ocean. Metagenomic-based ARG profiles showed a sudden increase of abundance and diversity in the surface layer of MT sediments reaching 2.73 × 10 copy/cell and 81 subtypes, and a high percentage of ∼63.6% anthropogenic pollution sources was predicted by the Bayesian-modeling classification method. These together suggested that ARG accumulation and anthropogenic impacts have already permeated into the bottom of the deepest corner on the earth. Moreover, six ARG-carrying draft genomes were retrieved using a metagenomic binning strategy, one of which assigned as was identified as a potential bacterial host to contribute to the ARG accumulation in MT, carrying F, M, Q, A2, PBP-2X, and PBP-1A. We propose that the MT ecosystem needs further long-term monitoring for the assessment of human impacts, and our identified three biomarkers (A2, F, and A) could be used for the rapid monitoring of anthropogenic pollution. Together our findings imply that anthropogenic pollution has penetrated into the deepest region of the ocean and urge for better pollution control to reduce the risk of ARG dissemination to prevent the consistent accumulation and potential threat to the natural environment.
了解抗生素耐药基因 (ARG) 的分布和传播对于理解人为因素对自然生态系统的影响至关重要。ARGs 通过水生环境的迁移非常重要，已受到广泛关注，但人为 ARG 污染是否已经对深海海洋生态系统造成影响尚未得到充分探索。为了研究生态健康问题，我们对马里亚纳海沟 (MT) （10890 米）沉积物中的 ARG 发生情况进行了分析，MT 是海洋的最深处。基于宏基因组的 ARG 图谱显示，MT 沉积物表层的丰度和多样性突然增加，达到 2.73×10 拷贝/细胞和 81 个亚型，贝叶斯模型分类方法预测约 63.6%的 ARG 具有人为污染来源。这些结果表明，ARG 的积累和人为影响已经渗透到地球上最深处的底部。此外，我们使用宏基因组 binning 策略还检索到了六个携带 ARG 的草案基因组，其中一个被鉴定为可能的细菌宿主，有助于 MT 中 ARG 的积累，携带 F、M、Q、A2、PBP-2X 和 PBP-1A。我们提出 MT 生态系统需要进一步的长期监测，以评估人为影响，我们鉴定的三个生物标志物 (A2、F 和 A) 可用于快速监测人为污染。总之，我们的研究结果表明，人为污染已经渗透到海洋的最深处，并迫切需要更好的污染控制措施来减少 ARG 传播的风险，以防止其在自然环境中的持续积累和潜在威胁。
