Coral-associated microbial communities in reef-building corals of Ningaloo Reef Western Australia

摘要: Coral reefs are at risk and human-induced environmental stressors in synergism with microorganisms have been shown to be the key players for their deterioration. Little is known about dynamics of coral-microbial associations through different life stages coral holobiont virtually nothing partners Western Australian reef systems. This project intended investigate presence, diversity, community structure role coral-associated microbes Ningaloo Reef spawning brooding corals. Different were assessed. To determine ‘normal ranges’ microbes, three species (Acropora tenuis, Pocillopora damicornis Favites abdita) tagged examined over a period one year, sampling deployed every months. One was additionally sampled on Rottnest Island, 1200km south Reef, provide comparisons between geographical areas. The analysed by phylogenetic analysis 16S rRNA gene clone libraries. Principal component (PCA) revealed that samples grouped according time not species, indicating may result drivers such as oceanographic characteristics, benthic temperature. Tissue from Island corals similarities bacteria Reef. study highlights microbial communities highly diverse; however, complex interactions stability these necessarily dependant host specificity. Reproduction plays crucial survival therefore, data acquired adult colonies, Acropora tenuis (broadcast spawner), (brooder) Tubastrea faulkneri (ahermatypic), before after mass if which changed this event. A contemporary 454 sequencing approach implemented results distinct bacterial shifts all corals, independently reproductive activity. Clear changes assemblages also detected brooders planulation. infers change event likely driven factors respective seawater, well actual reproduction. Differences reflected styles Most α-Proteobacteria increased abundance planulation, suggesting specific involved reproduction irrespective strategies; particularly affiliated Roseobacter clade followed pattern. The assessment seawater collected broadcast A. P. respectively strategy release offspring increases fitness following processes settlement survival. Species genera Alteromonas appear play important roles early history Isolates planulae mainly Vibrio found similar released mother colony during Finally establishment partnerships larval potential symbiotic relationships studied. onset visualized, exploring presence location organism, determining when how enter tissues cycling nutrients towards coral-symbiotic algal partners. Nano-scale Second Ion Mass Spectrometry (SIMS) applied detect, image map uptake translocation 15N into larvae sub-cellular level. combined Fluorescent In Situ Hybridisation (FISH) co-localize labelled substrate Transmission Electron Microscopy (TEM) allow ultra-structural resolution images high images. first demonstrated beneficial translocating nitrogen holobiont, nutrient-poor environments live in.