Coral associated bacteria Targeted Locus. uncultured bacterium

Bacteria associated with three species of coral before and after mass spawning. Bacteria associated with three coral species, Acropora millepora, Pocillopora damicornis and Tubastrea faulkneri, were assessed before and after coral mass spawning on Ningaloo Reef in Western Australia to correlate microbial diversity and community structure with coral reproductive stages and strategies. Two colonies of each species were sampled before and after the mass spawning event and two additional samples were collected for P. damicornis after planulation to allow comparison between brooding and spawning coral reproductive strategies. A variable 470 bp region of the 16S rRNA gene was selected for pyrosequencing to provide an understanding of potential variations in coral-associated bacterial diversity and community structure. Bacterial diversity increased for all coral species after spawning as assessed by Chao1 diversity indicators. Minimal changes in community structure were observed at the class level and data at the taxonomical level of genus incorporated into a PCA analysis indicated that despite bacterial diversity increasing after spawning, coral-associated community structure did not shift greatly with samples grouped according to species. However, interesting changes could be detected from the dataset; for example, á-Proteobacteria increased in relative abundance after coral spawning and particularly the Roseobacter clade was found to be prominent in all coral species, indicating this group, regardless of the corals' reproductive strategy may be important in coral reproduction and early coral life stages which has been proposed in previous studies.