Meta-analysis to identify the core microbiome in diverse wastewater

A meta-analysis was carried out using 20 publicly available metagenomic datasets obtained from diverse wastewater samples. A taxonomic assignment was performed, and the diversity measures were calculated. A total of 6,11,942 reads were analysed, and the sequences were assigned to 2605 operational taxonomic units (OTUs) based on ≥ 97% sequence identity. The taxonomic classification carried out at the phyla level indicated that Proteobacteria , Firmicutes , and Bacteroidetes were the dominant bacterial phyla. At the genera level, Comamonas , Pseudomonas , Acidovorax , Arcobacter , and Acinetobacter were prevalent across most wastewaters, forming the core microbial genera. Similarly, Burkholderiaceae , Rhodocyclaceae , Ruminococcaceae , Rhodobacteraceae , and Rhizobiaceae formed the core microbial families across the selected wastewaters. Spearman correlation analysis showed positive and negative correlations between the identified core microbiome, indicating the symbiotic relationship among bacteria involved in bioremediation. Metabolic pathway analysis indicated the presence of genes related to xenobiotics biodegradation and metabolism pathways in the datasets analysed. Majority of the wastewaters harbored an unclassified and uncultured bacterial consortia, indicating a novel microbiome yet to be characterised. Diversity analysis showed similarity in the habitation of microbiome irrespective of the physico-chemical nature and characteristics of wastewaters. As a comprehensive survey of diverse wastewater microbiome, this study provides insights into the core microbial diversity that could improve the existing bioremediation strategies.