| 摘要: |
| 近年来，抗生素抗性基因(antibiotic resistance genes, ARGs)及其介导的抗生素耐药性已成为备受关注的新兴环境问题，对生态安全和人类健康构成潜在威胁。已有研究表明，藻华能够影响ARGs的组成与分布，但目前关于黄海绿潮对ARGs分布特征及传播机制的影响尚不明确。该研究以受黄海绿潮影响严重的青岛近海为研究区域，采用宏基因测序技术，系统解析了浒苔绿潮对ARGs分布特征与传播机制的影响。暴发期和消亡期均以四环素类抗性基因(tetracycline)和大环内酯类抗性基因(mls)为主，但四环素类抗性基因的相对丰度在消亡期显著上升。两个时期的优势亚型均为tetA，但消亡期的相对丰度更高。除此之外，暴发期优势亚型为bacA、ugd、lnu(H)和rphB，消亡期为macB、bacA、novA和qacE。ARG宿主群落组成也差异显著，蓝藻纲(Cyanophyceae)在暴发期占比较高，在消亡期显著下降；消亡期则以α-变形菌纲(Alphaproteobacteria)、γ-变形菌纲(Gammaproteobacteria)和黄杆菌纲(Flavobacteriia)为主，且相对丰度高于暴发期。与暴发期相比，消亡期ARGs造成的潜在耐药宿主传播风险与抗性风险相对较高。此外，研究还检测到6种人类病原体细菌(human pathogenic bacteria, HPB)。研究结果揭示了浒苔绿潮对青岛近海ARGs分布特征、宿主组成及潜在传播风险的影响，为深化藻华影响下ARGs传播机制的认识以及海洋ARGs风险评估与治理提供科学依据。 |
| 关键词: 抗生素抗性基因 黄海绿潮 分布特征 传播机制 宏基因测序 |
| DOI：10.11693/hyhz20260400106 |
| 分类号: |
| 基金项目:山东省自然科学基金项目, ZR2024QD036号 |
|
| ZHENG D, YIN G, LIU M, et al, 2021. A systematic review of antibiotics and antibiotic resistance genes in estuarine and coastal environments [J]. Science of the Total Environment, 777: 146009.ZHU Y G, ZHAO Y, LI B, et al, 2017. Continental-scale pollution of estuaries with antibiotic resistance genes [J]. Nature Microbiology, 2: 16270. |
|
WU Pei-Xiao1,2,3, CHEN Xiao-Zhong1,2,3, SHAO Hong-Bing1,2,3, HE Hui1,2,3, CUI Dan-Hua4, WANG Min1,2,5,6
|
|
1.College of Marine Life Sciences, MOE Key Laboratory of Evolution &2.Marine Biodiversity and Institute of Evolution &3.Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China;4.Qingdao Eighth People’s Hospital, Qingdao 266121, China;5.Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System;6.Haide College, UMT-OUC Joint Centre for Marine Studies, Ocean University of China
|
| Abstract: |
| In recent years, antibiotic resistance genes (ARGs) and the antibiotic resistance they mediate have emerged as growing environmental concern, which pose potential threats to ecological security and human health. Previous studies have shown that algal blooms can affect the composition and distribution of ARGs; however, the effects of Ulva prolifera green tide in the Yellow Sea on the distribution characteristics and transmission mechanisms of ARGs remain unclear. In this study, the coastal waters of Qingdao, which are heavily affected by green tides, were selected as the studied areas. Metagenomic sequencing was employed to systematically elucidate the impacts of U. prolifera green tide on distribution characteristics and transmission mechanisms of ARGs. Tetracycline resistance genes and macrolide-lincosamide-streptogramin (mls) resistance genes were the dominant ARG types at both phases, with tetracycline resistance genes exhibiting a marked increase in relative abundance at the decline phase. The dominant ARG subtype at both phases was tetA, but its relative abundance was higher at the decline phase. In addition, the dominant subtypes at the outbreak phase mainly included bacA, ugd, lnu(H) and rphB, whereas those were macB, bacA, novA and qacE at the decline phase. The composition of the ARG host community also differed significantly between phases. Cyanophyceae accounted for a higher proportion at the outbreak phase but decreased significantly at the decline phase. In contrast, Alphaproteobacteria, Gammaproteobacteria and Flavobacteriia dominated the decline phase, and their relative abundances were all higher than those at the outbreak phase. Compared with the outbreak phase, ARGs posed relatively higher potential transmission and health risks at the decline phase. In addition, six human pathogenic bacteria (HPB) were detected in this study. These findings reveal the effects of U. prolifera green tide on the distribution characteristics, host composition and potential transmission risks of ARGs in the coastal waters of Qingdao, and provide a scientific basis for deepening the understanding of ARG transmission mechanisms under algal bloom conditions as well as for the risk assessment and management of marine ARGs. |
| Key words: antibiotic resistance genes green tides in the Yellow Sea distribution patterns transmission mechanisms metagenomic sequencing |