With the recent growing interest of antibiotic resistance genes (ARGs) and their co-selection with heavy metal resistance genes (HMRGs), their relationship to heavy metals needs further analysis. This study examined the response of heavy metal resistant microorganisms (HMRMs) and antibiotic resistant microorganisms (ARMs) and their resistance genes (HMRGs and ARGs) to Cu and Cr stresses using metagenome. Results showed that Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, and Nitrospirae are the dominant HMRMs and ARMs, with majority of HMRMs taxa presenting changes similar to ARMs under heavy metal stresses. Types of HMRGs and ARGs changed (increased or decreased) under Cu and Cr stresses, and a significant relationship was noted between HMRGs and ARGs and their related microbe (p < 0.05). Network analysis revealed synergistic relationships between majority of HMRGs and ARGs; however, negative correlations were also noted between them. Co-occurrence of HMRGs and ARGs was mainly observed in chromosomes, and plasmids were found to provide limited opportunities for heavy metals to promote antibiotic resistance through co-selection. These findings imply that the response of HMRMs and ARMs is induced by heavy metals, and that the changes in these microbial communities are the main factor driving the diversity and abundance of HMRGs and ARGs.

随着最近抗生素抗性基因 (ARGs) 及其与重金属抗性基因 (HMRGs) 的共同选择越来越受到关注，它们与重金属的关系需要进一步分析。本研究使用宏基因组检测了重金属抗性微生物 (HMRM) 和抗生素抗性微生物 (ARM) 及其抗性基因 (HMRGs 和 ARG) 对铜和铬胁迫的响应。结果表明，Alphaproteobacteria、Betaproteobacteria、Gammaproteobacteria、Deltaproteobacteria 和 Nitrospirae 是主要的 HMRM 和 ARM，大多数 HMRM 分类群在重金属胁迫下呈现与 ARM 相似的变化。HMRGs和ARGs的类型在Cu和Cr胁迫下发生变化（增加或减少），并且HMRGs和ARGs及其相关微生物之间存在显着关系（p <0.05）。网络分析揭示了大多数 HMRGs 和 ARGs 之间的协同关系；然而，也注意到它们之间存在负相关。HMRGs 和 ARGs 的共存主要在染色体中观察到，并且发现质粒为重金属通过共选择促进抗生素抗性提供了有限的机会。这些发现意味着HMRMs和ARMs的反应是由重金属诱导的，这些微生物群落的变化是驱动HMRGs和ARGs多样性和丰度的主要因素。发现质粒为重金属通过共选择促进抗生素抗性提供了有限的机会。这些发现意味着HMRMs和ARMs的反应是由重金属诱导的，这些微生物群落的变化是驱动HMRGs和ARGs多样性和丰度的主要因素。发现质粒为重金属通过共选择促进抗生素抗性提供了有限的机会。这些发现意味着HMRMs和ARMs的反应是由重金属诱导的，这些微生物群落的变化是驱动HMRGs和ARGs多样性和丰度的主要因素。