Characterization of microbial community structure in the octocoral Leptogorgia virgulata

Characterization of microbial community structure in the octocoral Leptogorgia virgulata" (2011). Honors Theses. 1 This thesis has been accepted as part of the honors requirements in the Department of Biology. _____________________________________ ____________________ (advisor signature) (date) _____________________________________ ____________________ (reader signature) (date) 2 Abstract The process of spicule formation in L. virgulata results in a drop in pH, which, if left unregulated, could lead to demineralization and subsequent animal death. Carbonic anhydrase has been suggested as a possible pH regulatory mechanism in L. virgulata tissues. This study focuses on an additional hypothetical mechanism of pH regulation involving the production of urease by endosymbiotic bacteria living within L. virgulata tissue. PCR and DGGE are used as culture-independent methods to characterize facets of microbial community structure on L. virgulata in order to identify one or many urease-producing endosymbionts. DGGE analysis shows high diversity among the microbial community within L. virgulata and varying community structure on different tissue types. Future sequencing of bacterial 16S rDNA fragments will yield significant clues about the possible bacterial relationship involved in L. virgulata spicule development.