Preliminary analysis of bacterial diversity associated with the Porites coral from the Arabian Sea

It is widely reported that coral reefs are suffering degradation from a combination of stresses. We have previously reported the use of genomic tools in the study of environmental impact assessment and hypothesize that monitoring the bacterial diversity associated with a coral would indicate changes in its health before visible damage occurs. This study analyzes the bacterial diversity associated with Porites coral collected from two sites in the Arabian Sea using culture independent techniques. Two clone libraries were constructed from the16S rDNA amplicons and selected individual clones were partially sequenced. Retrieved sequences were identified by BLAST analysis and indicate the presence of unidentified bacteria. Diversity index was calculated using Shannon-Wiener index. The bacterial diversity associated with coral sample 1 gives the index of species diversity, H (1) as 1.6287, divergence from eqiprobability as 45.708% and the evenness of the sample as 54.291. For coral sample 2, the values obtained were, H (1) as 1.97, divergence from eqiprobability as 15.11% and the evenness of the sample as 84.88. Sequences representing bacteria related to agricultural or industrial pollution and pathogenesis were also found. Coral samples collected near a lagoon area, showed a greater percentage of sequences representing bacteria related to human interventions, indicative of pollution.