Phylogenetic Diversity of Bacterial Community Associated with the Marine Sponge Halichondira nigrocutis Collected off Southwest Indian Coast

Abstract

This study aimed to evaluate the bacterial communities associated with the marine sponge Halichondria nigrocutis present in Indian waters by both cultivation and cultivation-independent techniques. Results using cultivation method showed that bacteria belonging to Bacillus, Acinetobacter and Vibrio spp. to be the predominant groups. Metagenomic study of sponge-associated bacteria by cultivation independent approach, involving cloning and sequencing of the 16S rDNA gene generated sequences that were subjected to phylogenetic analysis. Results demonstrated the community structure to be represented by the phyla Proteobacteria (alpha-, gamma- and delta-classes), Cyanobacteria, Actinobacteria and Firmicutes, with isolates belonging to alpha-proteobacterial group to be predominating. To our knowledge this study appears to be the first to record cultivable and uncultivable bacterial groups associated with H.nigrocutis from Indian waters.