The vertically-stratified resistomes in mangrove sediments was driven by the bacterial diversity

• Published in: Journal of hazardous materials Vol. 458; p. 131974
• Main Authors: Zeng, Jiaxiong, Pan, Yu, Hu, Ruiwen, Liu, Fei, Gu, Hang, Ding, Jijuan, Liu, Songfeng, Liu, Shengwei, Yang, Xueqin, Peng, Yisheng, Tian, Yun, He, Qiang, Wu, Yongjie, Yan, Qingyun, Shu, Longfei, He, Zhili, Wang, Cheng
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-09-2023
• Subjects: Anti-Bacterial Agents; Antibiotic/metal resistance gene; Bacteria - genetics; Bacterial diversity; Genes, Bacterial; Humans; Mangrove sediments; Metagenome sequencing; Microbiota; Mobile genetic element; PCoA; Antibiotic/metal resistance gene; MCCs; ARGs; Bacterial diversity; Mangrove sediments; ACCs; MGEs; ECCs; CARD; NCBI SRA; Mobile genetic element; AMCCs; TPM; ARB; HGT; ANOVA; MLS; MRGs; ORFs; Metagenome sequencing
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2023.131974

Early evidence has elucidated that the spread of antibiotic (ARGs) and metal resistance genes (MRGs) are mainly attributed to the selection pressure in human-influenced environments. However, whether and how biotic and abiotic factors mediate the distribution of ARGs and MRGs in mangrove sediments under natural sedimentation is largely unclear. Here, we profiled the abundance and diversity of ARGs and MRGs and their relationships with sedimental microbiomes in 0–100 cm mangrove sediments. Our results identified multidrug-resistance and multimetal-resistance as the most abundant ARG and MRG classes, and their abundances generally decreased with the sediment depth. Instead of abiotic factors such as nutrients and antibiotics, the bacterial diversity was significantly negatively correlated with the abundance and diversity of resistomes. Also, the majority of resistance classes (e.g., multidrug and arsenic) were carried by more diverse bacterial hosts in deep layers with low abundances of resistance genes. Together, our results indicated that bacterial diversity was the most important biotic factor driving the vertical profile of ARGs and MRGs in the mangrove sediment. Given that there is a foreseeable increasing human impact on natural environments, this study emphasizes the important role of biodiversity in driving the abundance and diversity of ARGs and MRGs.
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•Multidrug and multimetal were the most abundant resistome classes in mangrove sediments.•Bacterial diversity was the most important driver of the vertically-stratified resistomes.•The negative relationship between bacterial diversity and resistomes was a conserved trait in different mangrove sediments.