**5. Prevalent metagenomes for bioremediation**

Metagenomes extracted from uncultured microbial communities from multiple contaminant sites are screened and further identified for degrading properties [71]. Microbial communities vary according to the characteristics of source and site of contamination [72]. A metagenomic analysis conducted on the heavy metal-contaminated groundwater revealed metagenomes of γ- and β-Proteobacteria dominated by *Rhodanobacter*-like γ-proteobacterial and *Burkholderia*like β-proteobacterial species from the habitat of extremely high levels of uranium, nitrate, technetium and various organic contaminants [73]. Moreover, multiple metagenome projects have been taking place around the world; we have sorted out a list of multiple environmental metagenome projects with top microbe having the highest percentage of presence in the metagenomic community (Table 2). Studies on microbial adaptation of toxic environments may give rise to trace new metagenomic communities useful for efficient bioremediation. Specific functions and interactions of microbial communities with respect to contaminationdegrading capabilities can be a result of environmental-based gene switching in the metage‐ nomes.


**Table 2.** List of multiple environmental metagenome projects with top microbe having the highest percentage of presence in the metagenomic community
