摘要

从汽油和柴油消耗中排出的颗粒是城市空气污染的主要组成部分，由于大气沉降到水和土壤中，这些颗粒可能通过直接吸入或其他途径进入人体。抗菌药物耐药性是现代医疗保健最严重的威胁之一。然而，汽油和柴油废气颗粒如何影响抗性基因（ARG）在各种环境中的发展和传播仍然是一个很大的未知数。本研究调查了97辛烷汽油，93辛烷汽油，轻柴油和船用重柴油四种代表性汽油和柴油机废气颗粒，对对大肠杆菌S17 - 1 (供体)和K12 (受体)两种机会性大肠杆菌水平转移ARGs的影响及其可能机制。结果表明，与对照相比，这四种代表性类型的纳米级颗粒诱导了共轭转移率的浓度依赖性增加。还确定了参与ARG加速转移的潜在机制，包括细胞内活性氧（ROS）的产生和由此引起的氧化应激，SOS应答，细胞形态的改变以及膜蛋白mRNA基因表达的改变和那些参与促进接合转移的人。这些发现为汽油和柴油机尾气颗粒物对抗微生物药物的耐药性风险提供了新的证据和机制见解，并强调了替代燃料减轻空气污染和健康风险的严格战略的意义和必要性。

Particles exhausted from petrol and diesel consumptions are major components of urban air pollution that can be exposed to human via direct inhalation or other routes due to atmospheric deposition into water and soil. Antimicrobial resistance is one of the most serious threats to modern health care. However, how the petrol and diesel exhaust particles affect the development and spread of antimicrobial resistance genes (ARGs) in various environments remain largely unknown. This study investigated the effects and potential mechanisms of four representative petrol and diesel exhaust particles, namely 97 octane petrol, 93 octane petrol, light diesel oil, and marine heavy diesel oil, on the horizontal transfer of ARGs between two opportunistic Escherichia coli (E. coli) strains, E. coli S17-1 (donor) and E. coli K12 (recipient). The results demonstrated that these four representative types of nano-scale particles induced concentration-dependent increases in conjugative transfer rates compared with the controls. The underlying mechanisms involved in the accelerated transfer of ARGs were also identified, including the generation of intracellular reactive oxygen species (ROS) and the consequent induction of oxidative stress, SOS response, changes in cell morphology, and the altered mRNA expression of membrane protein genes and those involved in the promotion of conjugative transfer. The findings provide new evidences and mechanistic insights into the antimicrobial resistance risks posed by petrol and diesel exhaust particles, and highlight the implications and need for stringent strategies on alternative fuels to mitigate air pollution and health risks.

https://www.sciencedirect.com/science/article/pii/S0160412017319499