Temperature Effects on Microbial Communities of Sea Fan Coral as an Indicator of Disease Susceptibility

Coral reefs are in decline due to increases in coral disease. We suspect that one of the main sources of coral immunity is the strength the residential, native microbiota. Based on vertebrate models I suspect that disturbing the normal microbial community will lead to disease. The goal of this study is to use the coral-microbiota-disease hypothesis as a tool to establish how an increase in sea surface temperature leads to disease. I tested this by first exposing cuttings of sea fan coral (Gorgonia ventalina) to average summer sea surface temperature as well as to higher than average temperatures. Then, I analyzed the microbial community structure using denaturing gradient gel electrophoresis (DGGE). Finally, I identified individual bands through sequencing. I found that there were not significant differences in the microbial communities due to changes in temperature. However, the microbial community structures varied greatly when comparing coral on reefs and those in aquaria.