Potential threat of antibiotics resistance genes in bioleaching of heavy metals from sediment
Potential threat of antibiotics resistance genes in bioleaching of heavy metals from sediment
复制标题
抗生素抗性基因对沉积物中重金属生物浸出的潜在威胁
DOI：
10.1016/j.scitotenv.2021.152750
复制
发表时间：
2022
影响因子：
9.8
通讯作者：
Lou Liping
中科院分区：
文献类型：
--
作者：
Hu Xinyi;Wu Chuncheng;Shi Hongyu;Xu Weijian;Hu Baolan;Lou Liping
生物淋滤是一种很有前途的沉积物重金属污染修复技术。在生物浸出过程中，来自生物浸出的金属的压力更可能导致抗生素抗性基因（ARG）的传播。比较了土著菌和功能菌剂两种典型的重金属生物淋滤处理中ARGs丰度的变化。结果表明，两种处理均能成功地对重金属进行生物淋滤，其中功能菌剂对Cu的去除率更高。大多数ARGs的绝对丰度在生物淋滤后下降了一个log单位，特别是tetR（p = 0.02）和tetX（p = 0.04），而intI1从106拷贝/g下降到104拷贝/g。在相对丰度方面，非药物治疗组ARG从3.90 × 10 − 4增加到1.67 × 10 − 3拷贝/16S rRNA基因拷贝（p = 0.01），药物治疗组达到6.65 × 10 − 2拷贝/16S rRNA基因拷贝，而intI1相对丰度维持在10 − 3拷贝/16S rRNA基因拷贝。与外排泵机制和核糖体保护机制相关的ARGs相对丰度增加最多。共现网络分析表明，铜的生物淋滤是决定ARGs分布的环境因子，厚壁蚁可能是ARGs的潜在寄主。与土著细菌的生物浸出相比，功能菌剂的添加导致微生物α多样性的减少和Cu生物浸出量的增加，导致ARGs的相对丰度更高。两种生物淋滤处理均能有效去除沉积物中的重金属污染，但需考虑其对ARGs增殖的风险，尤其是功能菌剂处理。今后，应开发一种经济有效的绿色技术，同时减少精氨酸的绝对丰度和相对丰度。
Bioleaching is considered a promising technology for remediating heavy metals pollution in sediments. During bioleaching, the pressure from the metals bioleached is more likely to cause the spread of antibiotic resistance genes (ARGs). The changes in abundance of ARGs in two typical heavy metal bioleaching treatments using indigenous bacteria or functional bacteria agent were compared in this study. Results showed that both treatments successfully bioleached heavy metals, with a higher removal ratio of Cu with functional bacteria agent. The absolute abundances of most ARGs decreased by one log unit after bioleaching, particularlytetR (p= 0.02) andtetX (p= 0.04), andintI1 decreased from 106to 104copies/g. As for the relative abundance, ARGs in the non-agent treatment increased from 3.90 × 10−4to 1.67 × 10−3copies/16S rRNA gene copies (p= 0.01), and in the treatment with agent, it reached 6.65 × 10−2copies/16S rRNA gene copies, andintI1 relative abundance was maintained at 10−3copies/16S rRNA gene copies. The relative abundance of ARGs associated with efflux pump mechanism and ribosomal protection mechanism increased the most. The co-occurrence network indicated that Cu bioleached was the environmental factor determining the distribution of ARGs,Firmicutesmight be the potential hosts of ARGs. Compared to bioleaching with indigenous bacteria, the addition of functional bacteria agent engendered a decrease in microbial alpha diversity and an increase in the amount of Cu bioleached, resulting in a higher relative abundance of ARGs. Heavy metal pollution can be effectively removed from sediments using the two bioleaching treatments, however, the risk of ARGs propagation posed by those procedures should be considered, especially the treatment with functional bacteria agents. In the future, an economical and efficient green technology that simultaneously reduces both the absolute abundance and relative abundance of ARGs should be developed.