Metagenomic analysis of soil samples collected from estuarine mangroves of Arabian Sea reveals rich microbiota and high numbers of sulphate reducing bacteria accompanied with methanogen bacteria.

This study reports the analyses of the microbiome of the estuarine soil of mangroves of the Arabian Sea. Mangroves soil samples were collected from 12 locations of Arabian Sea coast of Maharashtra, India. 16S rRNA gene V3-V4 region amplicon sequencing was performed using the Miseq Illumina platform to identify the microbial communities present in the mangroves ecosystem. The metagenomics analysis provided an insight into the abundance, diversity and spatial variations in the mangrove microbial communities in relation to physico-chemical parameters and revealed that Proteobacteria, Flavobacteria and Planctomycetes are abundant in mangroves system. The differences in bacterial abundance, composition and diversity can partly be attributed to the physico-chemical characteristics of the samples, geographical location and anthropogenic activities in the locality. High numbers of sulphate reducing bacteria accompanied with methanogen bacteria were characteristic of Indian mangroves. The results obtained in the current study indicate rich species diversity and add valuable insights about the diversity of microbial communities of the mangroves in Maharashtra along the west coast of India and can provide better information for effective measures for conservation of mangroves. GIS based prediction suggest that the sulphur utilizing communities are under threat from anthropogenic activities and may decline in future if immediate measures are not implemented.