摘要

       牲畜废水处理厂是环境中抗生素耐药性决定因素的重要储存库。该研究探讨了典型牲畜污水处理厂中五种抗生素抗性基因（ARGs，包括 sulI、tetA、qnrD、mphB 和 mcr-1）和 1 类整合子 (intI1) 的流行情况，并分析了它们与两种金属抗性的综合关联基因（copA 和 czcA）、两种病原体基因（葡萄球菌和弯曲杆菌）、细菌群落和废水特性。结果表明在植物中检测到所有研究的基因。处理厂不能完全去除 ARGs 丰度，最多 2.2×104~3.7×108 份/L 的 ARGs 残留在流出物中。在随后的池塘中，Mcr-1 进一步富集了 27 倍。相关性分析表明，mphB 与 tetA 和 intI 显着相关。 Mcr-1 与 copA 强相关。 MphB 和 intI 与 czcA 显着相关。这些相关性暗示了细菌对抗生素和金属具有抗性的潜在共同选择风险。冗余分析表明，qnrD 和 mcr-1 分别与 13 和 14 个细菌属强相关。大多数 ARG 与废水养分呈正相关，表明有效减少废水养分将有助于控制抗生素耐药性。该研究将对牲畜设施和接收环境中 ARG 的归宿和减少提供有用的影响。

       The livestock wastewater treatment plant represents an important reservoir of antibiotic resistance determinants in the environment. The study explored the prevalence of five antibiotic resistance genes (ARGs, including sulI, tetA, qnrD, mphB and mcr−1) and class 1 integron (intI1) in a typical livestock wastewater treatment plant, and analyzed their integrated association with two metal resistance genes (copA and czcA), two pathogens genes (Staphylococcus and Campylobacter), bacterial community and wastewater properties. Results indicated that all investigated genes were detected in the plant. The treatment plant could not completely remove ARGs abundances, with up to 2.2 × 104~3.7 × 108 copies/L of them remaining in the effluent. Mcr−1 was further enriched by 27-fold in the subsequent pond. The correlation analysis showed that mphB significantly correlateed with tetA and intI. Mcr−1 strongly correlated with copA. MphB and intI significantly correlated with czcA. The correlations implied a potential co-selection risk of bacterial resistant to antibiotics and metals. Redundancy analyses indicated that qnrD and mcr−1 strongly correlated with 13 and 14 bacterial genera, respectively. Most ARGs positively correlated to wastewater nutrients, indicating that an efficient reduction of wastewater nutrients would contribute to the antibiotic resistance control. The study will provide useful implications on fates and reductions of ARGs in livestock facilities and receiving environments.

https://www.sciencedirect.com/science/article/abs/pii/S0147651318304354