Metagenomic profiling of diversified marine microbiome across microplastic-contaminated niches of Bay of Bengal, India

Diverse microorganisms in the marine sediment share a significant section of the global marine ecosystem and play a dominant role in marine biogeochemistry. The present study is the first to report an evaluation of shotgun metagenomic sequencing of microplastic-contaminated marine water and sediment samples from the coastal shores of the Bay of Bengal, India, across a stretch of 25 km, which houses a plethora of ubiquitous and uncultured microbial biodiversity coexisting with multitudinous human interventions. Illumina Nova sequencing 6000 suggested the presence of 88,539 scaffolds of data containing 132,568 identified genes of marine microorganisms. Taxonomic identification with the assistance of curated global databases ensued in the presence of Proteobacteria (53.12 %), Bacteroidetes (7.13 %), Actinobacteria (5.87 %), and miscellaneous (33.86 %) in abundance. Azonexus hydrophillus, Mycobacteroides abscessus, and Acidaminobacter hydrogenoformans were identified in profusion from the sequenced samples of the study area. The adaptation, sustenance, and survivability in the presence of plastic pollutants confirm the presence of microplastic-degrading enzymes in the microorganisms. The functional annotations revealed 54.32 % and 58.34 % similarities in genes with KEGG and COG databases, revealing the heavy presence of inorganic and amino acid transport channels. Further metabolic profiling of the identified novel microorganisms will assist in engineering the enhancement of microbial enzymes, such as cutinases, lipases, and esterases, leading to microplastic degradation activity. The present research work signifies the analysis and documentation of native microbiota of the marine shores of the Bay of Bengal and their interactive potentialities with microplastic-contaminated anthropogenic environments.