摘要
      十六烷基三甲基氯化铵（ATMAC-C16）是一种季铵化合物，广泛用作消毒剂、抗菌剂和表面活性剂。在这里，部分硝化/厌氧氨氧化（PN/A）系统暴露于不同水平的ATMAC-C16（0–10 mg/L），主要目的是揭示PN/A系统对ATMAC-C6的长期微生物反应，重要的是，探索PN/A对ATMAC-C16和关键抗性菌株的耐受性。ATMAC-C16的环境和极端水平主要通过影响anammox（hzsB）基因来影响脱氮效率。在ATMAC-C16的压力下富集了两种类型的厌氧氨氧化菌Candidatus Jettenia和Candidatu Kuenenia，这使PN/A系统保持了良好的脱氮性能。ATMAC-C16可能引起PN/A系统中整个微生物种群的兴奋，从而提高细胞活力。ATMAC-C16降低了大多数抗生素抗性基因（ARGs）的相对丰度，但显著富集了QACs抗性基因（QRGs）。PN/A系统对ATMAC-C16的耐受性可能通过诱导编码基因（qacH-01/02）的外排泵来增强。ARGs和QRG之间的微生物宿主动态和共选择机制导致了qacEdeltal-01/02和qacH-01/02的相反趋势。墨西哥假黄单胞菌被鉴定为ATMAC-C16抗性菌株，其对10mg/L ATMAC-C19的抗性不仅可以通过捕获qacH基因获得，还可以得益于其自身的外排泵系统。因此，从耐药基因，特别是QRG的传播角度来看，应重视QRG和ATMAC-C16耐药菌株在PN/A技术中的传播风险。
Abstract
Hexadecyl trimethyl ammonium chloride (ATMAC-C16) is a kind of quaternary ammonium compound (QACs) which is extensively consumed as disinfectants, antimicrobials and surfactants. Here, the partial nitrification/anammox (PN/A) system was exposed to different levels of ATMAC-C16 (0–10 mg/L) and the main objective was to reveal the long-term microbiological responses of PN/A system to ATMAC-C16, importantly, explore the tolerance of PN/A to ATMAC-C16 and the key resistant strain. Nitrogen removal efficiency was influenced by environmental and extreme levels of ATMAC-C16 through mainly affecting the anammox (hzsB) gene. Two types of anammox, Candidatus Jettenia and Candidatus Kuenenia, were enriched under the pressure of ATMAC-C16, which allowed PN/A system to maintain good nitrogen removal performance. ATMAC-C16 might cause the hormesis of entire microbial population in PN/A system, leading to the enhancement of cell viability. ATMAC-C16 decreased the relative abundances of most antibiotics resistance genes (ARGs) but significantly enriched QACs resistance genes (QRGs). The tolerance of PN/A system to ATMAC-C16 might be strengthened by inducing the efflux pumps encoding genes (qacH-01/02). Microbial hosts dynamic and co-selection mechanism among ARGs and QRGs resulted in the opposite trends of qacEdeltal-01/02 and qacH-01/02. Pseudoxanthomonas mexicana was identified as the ATMAC-C16 resistant strain, and its resistance to 10 mg/L ATMAC-C16 might not only obtain by capturing the qacH gene, but also benefit from its own efflux pump system. Therefore, from the perspective of the transmission of resistance genes, especially for QRGs, the spread risk of QRGs and ATMAC-C16 resistant strain in PN/A technique should be taken seriously.

https://www.sciencedirect.com/science/article/abs/pii/S0043135422003499