INVESTIGATION OF SPATIAL AND SEASONAL MICROBIOME DYNAMICS AND ASSOCIATED ANTIBACTERIAL ACTIVITY IN SCLERACTINIAN CORAL PLATYGYRA DAEDALEA IN THE ARABIAN GULF

Abstract

Corals have critical interactions with their associated microbes, which play an integral part in maintaining coral health and stability. Environmental factors can influence the microbial community of the coral resulting in dysbiosis which often correlates with the appearance of disease. However, the foundational understanding of variations in coral microbiomes in response to environmental factors across spatial and temporal scales is limited. In this study, 16s rRNA sequencing was utilized to study the spatial and seasonal dynamics of the microbiome of the coral Platygyra daedalea in Qatari reefs. P. daedalea microbiomes displayed significant variability in diversity and abundance among the 5 study sites. On the other hand, although there were apparent variations in microbiome composition between summer and winter, there was no evidence to support these variations were seasonal, indicating that P. daedalea microbiome is mainly driven by reef location. Analysis of the free-living microbial communities identify potential microbial taxa as indicators of environmental perturbations that can influence coral health. Fifty coral associated bacteria were isolated from P. daedalea comprising of 13 families belonging to Proteobacteria, Firmicutes and Bacteroidetes. Investigation of the antimicrobial activity of coral associated bacteria emphasized that microbial interactions regulate microbiome community structure. Pseudovibrio denitrificans N40 exhibited strong activity against 40% of the cultured coral isolates.