摘要
      生物气溶胶由于其对气候、生态环境和人类健康的影响而受到广泛关注。本研究旨在揭示PM2.5中细菌群落组成的驱动因素和抗生素抗性基因（ARGs）的传播途径。结果表明，春季细菌浓度（8.76×105拷贝/m3）显著高于夏季（1.03×105拷贝g/m3）和冬季（4.74×104拷贝/m3）。冬季的低温和空气污染对细菌浓度产生了负面影响。通过网络分析确定了Keystone分类群。尽管大约50%的关键类群的相对丰度较低，但关键类群和其他类群之间复杂的相互作用对细菌群落结构的强烈影响值得关注。细菌群落聚集以随机过程为主（79.3%）。细菌和环境过滤之间的相互作用共同影响了细菌群落的组成。垂直基因转移在空气传播ARGs中发挥了重要作用。鉴于ARGs在受体中的潜在整合和表达，不能忽视由于高浓度ARGs和可移动遗传元素导致的人类暴露风险。这项研究强调了人类在城市地区接触可吸入细菌病原体和ARGs的情况。
Abstract
Bioaerosols have received extensive attention due to their impact on climate, ecological environment, and human health. This study aimed to reveal the driving factors that structure bacterial community composition and the transmission route of antibiotic resistance genes (ARGs) in PM2.5. The results showed that the bacterial concentration in spring (8.76 × 105 copies/m3) was significantly higher than that in summer (1.03 × 105 copies/m3) and winter (4.74 × 104 copies/m3). Low temperatures and air pollution in winter negatively affected bacterial concentrations. Keystone taxa were identified by network analysis. Although about 50 % of the keystone taxa had low relative abundances, the strong impact of complex interactions between keystone taxa and other taxa on bacterial community structure deserved attention. The bacterial community assembly was dominated by stochastic processes (79.3 %). Interactions between bacteria and environmental filtering together affected bacterial community composition. Vertical gene transfer played an important role in the transmission of airborne ARGs. Given the potential integration and expression of ARGs in recipients, the human exposure risk due to high concentrations of ARGs and mobile genetic elements cannot be ignored. This study highlights human exposure to inhalable bacterial pathogens and ARGs in urban areas.

https://www.sciencedirect.com/science/article/abs/pii/S0304389422023913