Pathogenic Bacteria Associated with Coral Disease in Chuuk Island

Abstract

Understanding patterns of microbial diversity and composition in the coral is essential to assess the impact of microbes on marine ecosystem. Although the potential roles of microbes in coral were revealed, their diversity and their effects on coral disease are still unclear. In this study, we used a 16S rRNA gene taq-pyrosequencing technique to investigate the bacterial communities associated with coral and the surrounding seawater in Chuuk, Micronesia. Our results showed 1160 and 1650 Operational Taxonomic Units (OTUs) were found at each sampling times, March and May. Altogether, over 26 bacterial phyla were recovered from coral and seawater, of which Proteobacteria was the most dominant group in both. In addition, the value of Shannon index, which measures the evenness of the distribution of individuals among OTUs, of seawater in seawater is higher than coral in March and May, displaying a higher diversity of bacteria. An interest thing is that the bacterial composition between coral and seawater showed distinct pattern. In particular, we found two bacteria which are associated with coral disease, Vibrio owenssi and Photobacterium rosenbergii. Species-specific primers were designed to target the barcode gene 16S rRNA from bacteria and were used to evaluate the presence of bacteria in coral. on coral disease are still unclear. In this study, we used a 16S rRNA gene taq-pyrosequencing technique to investigate the bacterial communities associated with coral and the surrounding seawater in Chuuk, Micronesia. Our results showed 1160 and 1650 Operational Taxonomic Units (OTUs) were found at each sampling times, March and May. Altogether, over 26 bacterial phyla were recovered from coral and seawater, of which Proteobacteria was the most dominant group in both. In addition, the value of Shannon index, which measures the evenness of the distribution of individuals among OTUs, of seawater in seawater is higher than coral in March and May, displaying a higher diversity of bacteria. An interest thing is that the bacterial composition between coral and seawater showed distinct pattern. In particular, we found two bacteria which are associated with coral disease, Vibrio owenssi and Photobacterium rosenbergii. Species-specific primers were designed to target the barcode gene 16S rRNA from bacteria and were used to evaluate the presence of bacteria in coral.