摘要

       了解含抗生素废水生物处理过程中整体抗生素抗性基因 (ARG) 的归宿是水生态安全评估的核心问题。虽然基于微生物电极呼吸的生物转化过程可以显着解毒一些抗生素污染物，例如氯霉素（CAP）、减少CAP的生物阴极微生物组和抵抗组对连续电刺激的反应，尤其是ARGs网络相互作用，我们知之甚少。在这里，使用高通量功能基因阵列 (GeoChip v4.6) 和 Illumina 16S rRNA 基因 MiSeq 测序，研究了响应连续电刺激的减少 CAP 的生物阴极微生物组和抵抗组的结构、组成、多样性和网络相互作用。我们的结果表明，与纯生物还原过程相比，CAP 生物电还原过程可以显着加速 CAP 在含 CAP 废水处理过程中抗菌活性的消除。连续电刺激可以明显改变微生物组和抵抗组结构，并持续降低 CAP 减少生物膜内的系统发育、功能和整体 ARG 多样性和网络复杂性。总体 ARGs 和特定 CAP 抗性相关的主要促进剂超家族 (MFS) 转运蛋白基因的相对丰度与 CAP 对无活性抗菌产物 AMCl（部分脱氯芳香胺）的还原效率呈显着负相关，这可能会降低与含抗生素废水处理过程中多重耐药菌和 ARGs 的演变。这项研究为抗生素减少生物阴极抵抗组对连续电刺激的反应提供了新的见解，并提供了有关评估抗生素污染物生物电化学处理的整体 ARG 风险的有用信息。

       Understanding the fate of overall antibiotic resistance genes (ARGs) during the biological treatment of antibiotic containing wastewater is a central issue for the water ecological safety assessment. Although the microbial electrode-respiration based biotransformation process could significantly detoxify some antibiotic contaminants, e.g. chloramphenicol (CAP), the response of CAP-reducing biocathode microbiome and resistome to continuous electrical stimulation, especially ARGs network interactions, are poorly understood. Here, using highthroughput functional gene array (GeoChip v4.6) and Illumina 16S rRNA gene MiSeq sequencing, the structure, composition, diversity and network interactions of CAP-reducing biocathode microbiome and resistome in response to continuous electrical stimulation were investigated. Our results indicate that the CAP bioelectroreduction process could significantly accelerate the elimination of antibacterial activity of CAP during CAP-containing wastewater treatment compared to the pure bioreduction process. Continuous electrical stimulation could obviously alter both the microbiome and resistome structures and consistently decrease the phylogenetic, functional and overall ARGs diversity and network complexity within the CAP-reducing biofilms. The relative abundances of overall ARGs and specific CAP resistance related major facilitator superfamily (MFS) transporter genes were significantly negatively correlated with the reduction efficiency of CAP to inactive antibacterial product AMCl (partially dechlorinated aromatic amine), which may reduce the ecological risk associated with the evolution of multidrug-resistant bacteria and ARGs during antibiotic-containing wastewater treatment process. This study offers new insights into the response of an antibiotic reducing biocathode resistome to continuous electrical stimulation and provides useful information on the assessment of overall ARGs risk for the bioelectrochemical treatment of antibiotic contaminants.

https://www.sciencedirect.com/science/article/abs/pii/S0043135418308765