Zhang Yan, Su Zhiguo, Qiu Xuyang, Liu He, Wen Donghui, Chen Lyujun
Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment & Ecology, Jiangnan University, Wuxi, 214122, China.
Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou, 215011, China.
Environ Sci Ecotechnol. 2025 Jun 3;26:100586. doi: 10.1016/j.ese.2025.100586. eCollection 2025 Jul.
Class 1 integrons facilitate horizontal gene transfer, significantly influencing antibiotic resistance gene (ARG) dissemination within microbial communities. Wastewater treatment plants (WWTPs) are critical reservoirs of ARGs and integrons, yet the integron-mediated dynamics of ARG transfer across different WWTP types remain poorly understood. Here we show distinct ARG profiles associated with class 1 integrons in municipal and industrial WWTPs using a novel approach combining nested-like high-throughput qPCR and PacBio sequencing. Although industrial WWTPs contained higher absolute integron abundances, their relative ARG content was lower (1.27 × 10-9.59 × 10 copies/ng integron) compared to municipal WWTPs (3.72 × 10-1.98 × 10 copies/ng integron). Of the 132,084 coding sequences detected from integrons, 56.8 % encoded antibiotic resistance, with industrial plants showing lower ARG proportions, reduced ARG array diversity, and greater incorporation of non-ARG sequences. These findings suggest industrial WWTP integrons integrate a broader array of exogenous genes, reflecting adaptation to complex wastewater compositions. This work enhances our understanding of integron-driven ARG dynamics in wastewater and offers a robust strategy for environmental integron analysis.
1类整合子促进水平基因转移，对微生物群落中抗生素抗性基因（ARG）的传播有显著影响。污水处理厂（WWTPs）是ARG和整合子的重要储存库，但不同类型污水处理厂中整合子介导的ARG转移动态仍知之甚少。在这里，我们使用一种结合巢式高通量qPCR和PacBio测序的新方法，展示了城市和工业污水处理厂中与1类整合子相关的不同ARG谱。尽管工业污水处理厂的整合子绝对丰度较高，但其相对ARG含量（1.27×10 - 9.59×10拷贝/纳克整合子）低于城市污水处理厂（3.72×10 - 1.98×10拷贝/纳克整合子）。从整合子中检测到的132,084个编码序列中，56.8%编码抗生素抗性，工业污水处理厂的ARG比例较低，ARG阵列多样性降低，非ARG序列的掺入更多。这些发现表明，工业污水处理厂的整合子整合了更广泛的外源基因阵列，反映了对复杂废水成分的适应性。这项工作增进了我们对污水处理中整合子驱动的ARG动态的理解，并为环境整合子分析提供了一种强大的策略。
