Functional and phylogenetic diversity assessment of microbial communities at Gulf of Kachchh, India: An ecological footprint

Abstract Analyzing microbial communities and their functional structure in an expeditious and extensive manner is very important to identify ecological indicators in the historically polluted niches. Thus, the present study aims to investigate the metabolic potential and phylogenetic diversity of oil and coal contaminated sediments of Navlkahi port (NAV), Gulf of Kachchh, Gujarat, India during two seasons viz. pre-monsoon (PreMN) and post-monsoon (PoMN) using NextSeq 499, a high throughput sequencing platform. Assessment of functional diversity of both metagenomes by SEED, Gene Ontology terms, Clusters of Orthologous Groups of protein categories, protein family numbers, and Kyoto Encyclopedia of Genes revealed xenobiotic compound degradation potential of indigenous microbial community. The results also revealed the higher abundance of genes involved in aromatic compound degradation, heavy metal resistance, stress response and other major biochemical cycles during PreMN season compared to PoMN. Taxonomic assessment suggests Alteromonadales were the predominant from phyla Proteobacteria at NAV. Apart from abundant microbial communities, “rare” community may also a play major role in the xenobiotic compound degradation. The statistical analysis indicates that the diversity and richness were almost similar during both the seasons. The existence of indicator microbial communities in xenobiotic compounds degradation and other major biochemical cycles in both contaminated metagenomes implies that stimulating indigenous microorganisms could be a valid option for remediating oil and coal contaminated sites. Moreover, the information generated from this experiment with high throughput sequencing may be the first report particularly with reference to functional and phylogenetic microbial diversity of coal and oil contaminated habitat.