Community-integrated multi-omics facilitates screening and isolation of the organohalide dehalogenation microorganism

A variety of anthropogenic organohalide contaminants generated from industry are released into the environment and thus cause serious pollution that endangers human health. In the present study, we investigated the microbial community composition of industrial saponification wastewater using 16S rRNA sequencing, providing genomic insights of potential organohalide dehalogenation bacteria (OHDBs) by metagenomic sequencing. We also explored yet-to-culture OHDBs involved in the microbial community. Microbial diversity analysis reveals that Proteobacteria and Patescibacteria phyla dominate microbiome abundance of the wastewater. In addition, a total of six bacterial groups (Rhizobiales, Rhodobacteraceae, Rhodospirillales, Flavobacteriales, Micrococcales, and Saccharimonadales) were found as biomarkers in the key organohalide removal module. Ninety-four metagenome-assembled genomes were reconstructed from the microbial community, and 105 hydrolytic dehalogenase genes within 42 metagenome-assembled genomes were identified, suggesting that the potential for organohalide hydrolytic dehalogenation is present in the microbial community. Subsequently, we characterized the organohalide dehalogenation of an isolated OHDB, Microbacterium sp. J1-1, which shows the dehalogenation activities of chloropropanol, dichloropropanol, and epichlorohydrin. This study provides a community-integrated multi-omics approach to gain functional OHDBs for industrial organohalide dehalogenation.

Automated summary

This study investigated the microbial community composition and potential organohalide dehalogenation bacteria (OHDBs) in industrial saponification wastewater using 16S rRNA sequencing and metagenomic sequencing. The study found that the dominant microbial phyla in the wastewater were Proteobacteria and Patescibacteria, and identified six bacterial groups as biomarkers for organohalide removal. A total of 105 hydrolytic dehalogenase genes were also identified in 42 reconstructed metagenomes, indicating the potential for organohalide hydrolytic dehalogenation in the microbial community. Additionally, the study characterized the dehalogenation activities of an isolated OHDB, Microbacterium sp. J1-1.