Comprehensive Patterns of Bacterial Diversity and Identification of Pathogenic Bacteria from KIOST Marine Resources Center in South Sea of Korea.

Abstract

Understanding patterns of microbial diversity and composition in the seawater is essential to assess the impact of microbes on ocean ecosystem. Although the potential roles of microbes in ocean were revealed, their diversity and relationships with environmental factors remain unclear. In this study, we adopted a 16S rRNA gene taq-pyrosequencing technique to investigate the bacterial communities associated with two different seasonal seawaters from South Sea of Korea. Our results revealed highly diverse bacterial communities up to 900 Operational Taxonomic Units (OTUs) estimated from each seawater which was sampled at March and May, when environment conditions differed significantly. Altogether, 13 bacterial phyla were recovered from the both seawaters, of which Proteobacteria was the most dominant group. In addition, the value of Shannon index, which measures the evenness of the distribution of individuals among OTUs, of seawater in May is higher than that in March, suggesting that it displays a wider diversity of bacteria. Interestingly, the proportion of pathogenic bacteria was significantly increased in May relative to March. In particular, Pseudoalteromona and Vibrios were only determined as pathogenic bacteria from both seawaters, and of which Vibrios were dominant.ps with environmental factors remain unclear. In this study, we adopted a 16S rRNA gene taq-pyrosequencing technique to investigate the bacterial communities associated with two different seasonal seawaters from South Sea of Korea. Our results revealed highly diverse bacterial communities up to 900 Operational Taxonomic Units (OTUs) estimated from each seawater which was sampled at March and May, when environment conditions differed significantly. Altogether, 13 bacterial phyla were recovered from the both seawaters, of which Proteobacteria was the most dominant group. In addition, the value of Shannon index, which measures the evenness of the distribution of individuals among OTUs, of seawater in May is higher than that in March, suggesting that it displays a wider diversity of bacteria. Interestingly, the proportion of pathogenic bacteria was significantly increased in May relative to March. In particular, Pseudoalteromona and Vibrios were only determined as pathogenic bacteria from both seawaters, and of which Vibrios were dominant.