Project description:Coral harbor diverse and specific bacteria play significant roles in coral holobiont function. Bacteria associated with three of the common and phylogenetically divergent reef-building corals in the South China Sea, Porites lutea, Galaxea fascicularis and Acropora millepora, were investigated using 454 barcoded-pyrosequencing. Three colonies of each species were sampled, and 16S rRNA gene libraries were constructed individually. Analysis of pyrosequencing libraries showed that bacterial communities associated with the three coral species were more diverse than previous estimates based on corals from the Caribbean Sea, Indo-Pacific reefs and the Red Sea. Three candidate phyla, including BRC1, OD1 and SR1, were found for the first time in corals. Bacterial communities were separated into three groups: P. lutea and G. fascicular, A. millepora and seawater. P. lutea and G. fascicular displayed more similar bacterial communities, and bacterial communities associated with A. millepora differed from the other two coral species. The three coral species shared only 22 OTUs, which were distributed in Alphaproteobacteria, Deltaproteobacteria, Gammaproteobacteria, Chloroflexi, Actinobacteria, Acidobacteria and an unclassified bacterial group. The composition of bacterial communities within each colony of each coral species also showed variation. The relatively small common and large specific bacterial communities in these corals implies that bacterial associations may be structured by multiple factors at different scales and that corals may associate with microbes in terms of similar function, rather than identical species.
Project description:In this study, the complete mitogenome sequence of Galaxy Coral, <i>Galaxea fascicularis</i> (Cnidaria: Oculinidae), has been sequenced by next-generation sequencing method. The overall base composition of <i>Galaxea fascicularis</i> mitogenome is 24.9% for A, 14.0% for C, 24.3% for G and 36.8% for T and has low GC content of 38.3%. The assembled mitogenome, consisting of 18 751 bp, has unique 13 protein-coding genes (PCGs), three transfer RNAs and two ribosomal RNAs genes. The <i>G. fascicularis</i> mitogenome has the common mitogenome gene organization and feature of scleractinian coral. Among 13 PCGs, ND5 gene is interrupted by group I intron (12?022?bp). There are 12 genes embedded in ND5 group I intron (tRNA-Leu, ND1, CYTB, ND2, ND6, ATP6, ND4, 12S rRNA, COX3, COX2, ND4L and ND3). The complete mitogenome provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis for stony coral.
Project description:Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
| S-EPMC3035286 | BioStudies
Project description:Bacterial communities of Galaxea fascicularis in Hainan Island
| PRJNA810598 | ENA
Project description:Bacterial communities of Galaxea fascicularis in Xisha Islands
Project description:The success of coral reef ecosystems largely depends on mutualistic symbiosis between scleractinian corals and the dinoflagellate photosymbiont Symbiodinium spp. However, further investigation is needed to elucidate the flexibility of coral-algae associations in response to environmental changes. In this study, we applied a molecular method (high-throughput internal transcribed spacer 2 region of ribosomal RNA gene amplicon sequencing) to explore diversity and flexibility of Symbiodinium associated with Galaxea fascicularis, an ecologically important scleractinian coral species collected at five locations around Hainan Island, South China Sea. The results revealed a high diversity of Symbiodinium subclades with C2r and D17 being dominant in G. fascicularis. Clade D Symbiodinium occurred most frequently in habitats where the annual average sea surface temperatures are the highest, suggesting that temperature is an important factor in determining Symbiodinium D abundance in G. fascicularis. The distribution of coral-Symbiodinium associations are possibly mediated by trade-off mechanisms which change the relative abundance of Symbiodinium clades/subclades under different environmental conditions. These findings provide further evidence that reef-building corals such as G. fascicularis can shuffle their symbionts to cope with environmental changes, and have implications for our understanding of the ecology of flexible coral-algal symbiosis.
Project description:Population connectivity resulting from larval dispersal is essential for the maintenance or recovery of populations in marine ecosystems, including coral reefs. Studies of species diversity and genetic connectivity within species are essential for the conservation of corals and coral reef ecosystems. We analyzed mitochondrial DNA sequence types and microsatellite genotypes of the broadcast-spawning coral, Galaxea fascicularis, from four regions in the subtropical Nansei Islands in the northwestern Pacific Ocean. Two types (soft and hard types) of nematocyst morphology are known in G. fascicularis and are significantly correlated with the length of a mitochondrial DNA noncoding sequence (soft type: mt-L; hard type: mt-S type). Using microsatellites, significant genetic differentiation was detected between the mitochondrial DNA sequence types in all regions. We also found a third genetic cluster (mt-L+), and this unexpected type may be a cryptic species of Galaxea. High clonal diversity was detected in both mt-L and mt-S types. Significant genetic differentiation, which was found among regions within a given type (F ST = 0.009-0.024, all Ps ? 0.005 in mt-L; 0.009-0.032, all Ps ? 0.01 in mt-S), may result from the shorter larval development than in other broadcast-spawning corals, such as the genus Acropora. Nevertheless, intraspecific genetic diversity and connectivity have been maintained, and with both sexual and asexual reproduction, this species appears to have a potential for the recovery of populations after disturbance.