Heat‐induced shift in coral microbiome reveals several members of the Rhodobacteraceae family as indicator species for thermal stress in Porites lutea

• Published in: MicrobiologyOpen (Weinheim) Vol. 8; no. 12; pp. e935 - n/a
• Main Authors: Pootakham, Wirulda, Mhuantong, Wuttichai, Yoocha, Thippawan, Putchim, Lalita, Jomchai, Nukoon, Sonthirod, Chutima, Naktang, Chaiwat, Kongkachana, Wasitthee, Tangphatsornruang, Sithichoke
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01-12-2019; John Wiley and Sons Inc; Wiley
• Subjects: Abundance; Algae; Animals; Anthozoa - microbiology; Aquariums; Bacteria; Biodiversity; Bleaching; Climate change; Community structure; Consortia; coral bleaching; coral microbiome; Coral Reefs; Corals; coral‐associated bacteria; Deoxyribonucleic acid; Diversity indices; DNA; DNA Barcoding, Taxonomic; Ecosystem; Endozoicomonas; Fungi; Genetic testing; Heat; heat stress; Heat tolerance; Hot Temperature; Indicator species; Metagenomics - methods; Microbiomes; Microbiota; Microorganisms; Original; PacBio sequencing; Porites lutea; Rhodobacteraceae; RNA, Ribosomal, 16S - genetics; rRNA 16S; Seawater; Stress, Physiological; Symbionts; Temperature tolerance; thermal bleaching; Thermal stress; Vibrio; Water temperature; Waterborne diseases; Thailand; Phuket Thailand; heat stress; Endozoicomonas; coral microbiome; PacBio sequencing; Rhodobacteraceae; Porites lutea; thermal stress; thermal bleaching; coral bleaching; coral-associated bacteria
• ISSN: 2045-8827; 2045-8827
• DOI: 10.1002/mbo3.935

The coral holobiont is a complex ecosystem consisting of coral animals and a highly diverse consortium of associated microorganisms including algae, fungi, and bacteria. Several studies have highlighted the importance of coral‐associated bacteria and their potential roles in promoting the host fitness and survival. Recently, dynamics of coral‐associated microbiomes have been demonstrated to be linked to patterns of coral heat tolerance. Here, we examined the effect of elevated seawater temperature on the structure and diversity of bacterial populations associated with Porites lutea, using full‐length 16S rRNA sequences obtained from Pacific Biosciences circular consensus sequencing. We observed a significant increase in alpha diversity indices and a distinct shift in microbiome composition during thermal stress. There was a marked decline in the apparent relative abundance of Gammaproteobacteria family Endozoicomonadaceae after P. lutea had been exposed to elevated seawater temperature. Concomitantly, the bacterial community structure shifted toward the predominance of Alphaproteobacteria family Rhodobacteraceae. Interestingly, we did not observe an increase in relative abundance of Vibrio‐related sequences in our heat‐stressed samples even though the appearance of Vibrio spp. has often been detected in parallel with the increase in the relative abundance of Rhodobacteraceae during thermal bleaching in other coral species. The ability of full‐length 16S rRNA sequences in resolving taxonomic uncertainty of associated bacteria at a species level enabled us to identify 24 robust indicator bacterial species for thermally stressed corals. It is worth noting that the majority of those indicator species were members of the family Rhodobacteraceae. The comparison of bacterial community structure and diversity between corals in ambient water temperature and thermally stressed corals may provide a better understanding on how bacteria symbionts contribute to the resilience of their coral hosts to ocean warming.
We examined the effect of elevated seawater temperature on the structure and diversity of bacterial populations associated with Porites lutea, using full‐length 16S rRNA sequences obtained from Pacific Biosciences circular consensus sequencing. The bacterial community structure shifted toward the predominance of Alphaproteobacteria family Rhodobacteraceae. On the other hand, there was a marked decline in the apparent relative abundance of Gammaproteobacteria family Endozoicomonadaceae after P. lutea had been exposed to elevated seawater temperature.