16S rDNA-based bacterial diversity analysis of Arabian Sea sediments: A metagenomic approach

Marine ecosystems are highly productive as they harbor different marine microorganisms. Analysis of microbial diversity from these ecosystems will help identify new microbes having specificity for unique applications. This study deals with the culture-independent assessment of bacterial community structure and diversity of Arabian Sea sediments based on sequence analysis of 16S rDNA clone library. The sequences classified into seven phyla of bacterial domain including members of phylum Proteobacteria, Bacteriodetes, Actinobacteria, Firmicutes, Chloroflexi, Deferribacter and Acidobacterium. Most sequences were identified as phylum Proteobacteria (62.80%), with a dominance of classes Alphaproteobacteria (58.46%) and Gammaproteobacteria (38.46%). 10.47% of the sequences did not fall into any taxonomic hierarchy suggesting the possibility of unexplored/unidentified ones in marine sediments. This study adds to the limited information about the Viable But Not Culturables (VBNCs) in the sediments of Arabian Sea. Further studies are essential to understand the diversity and function in detail.