Composition and Functional Characterization of Microbiome Associated with Mucus of the Coral Fungia echinata Collected from Andaman Sea

Abstract

This study describes the community composition and functions of the microbiome associated with the mucus of the coral Fungia echinata based on metagenomic approach. Metagenome sequence data showed a dominance of the class Gammaproteobacteria followed by Alphaproteobacteria, Betaproteobacteria, Deltaproteobacteria, Flavobacteriia, Bacilli, and Clostridia. At the order level, the most abundant groups were Pseudomonadales, Oceanospirillales, Alteromonadales, and Rhodobacterales. The genus Psychrobacter was the most predominant followed by Thalassolituus and Cobetia, although other genera were also present, such as Sulfitobacter, Pseudoalteromonas, Oleispira, Halomonas, Oceanobacter, Acinetobacter, Pseudomonas, Vibrio, and Marinobacter. The metabolic profile of the bacterial community displayed high prevalence of genes associated with core-housekeeping processes, such as carbohydrates, amino acids, proteins, and nucleic acid metabolism. Further, high abundance of genes coding for DNA replication and repair, stress response, and virulence factors in the metagenome suggested acquisition of specific environmental adaptation by the microbiota. Comparative analysis with other coral metagenome exhibits marked differences at the taxonomical and functional level. This study suggests the bacterial community compositions are influenced by the specific coral micro-niche and the oligotrophic marine environment.

Coral Bacterial-Core Abundance and Network Complexity as Proxies for Anthropogenic Pollution

“…This genus has been described as being vertically transmitted from parent to offspring in M. hispida ( Leite et al, 2017 ), which suggests a potential key role of this group for the holobiont. On the other hand, the genus Acinetobacter has been detected in a wide range of hosts ( Wegley et al, 2007 ; Shnit-Orland and Kushmaro, 2009 ; Sweet et al, 2013 ; Li Y. et al, 2014 ; Badhai et al, 2016 ; Meyer et al, 2016 ; Zhou et al, 2016 ; Leite et al, 2017 ), including many tropical corals ( Wegley et al, 2007 ; Sweet et al, 2013 ; Leite et al, 2017 ), where this genus has been considered as an effective first line of defense ( Santos et al, 2015 ; Leite et al, 2017 ) and also as potential pathogens ( Shnit-Orland and Kushmaro, 2009 ; Sweet et al, 2013 ; Li J. et al, 2014 ; Meyer et al, 2016 ).…”

Comparison of microbiomes of cold-water corals Primnoa pacifica and Primnoa resedaeformis, with possible link between microbiome composition and host genotype

“…Three families (Pseudomonadaceae, Bacillaceae, and Moraxellaceae) are core members of the mucus microbiome of Mussimilia hispida 40 . In addition, Pseudomonadaceae are core members of the Coelastrea aspera microbiome 34 and associate with numerous other tropical stony corals, including Stylophora pistillata 41 , Pachyseris speciosa 37 , Fungia echinata 42 , Orbicella faveolata 43 , O. annularis 43 , and Astrangia poculata 44 , whose range extends from tropical to temperate regions. This family of bacteria also populates the microbiomes of tropical soft corals 45 , 46 , as well as cold-water gorgonians 19 .…”

“…In addition to appearing as core members of the P. resedaeformis microbiome, Vibrionaceae bacteria were recently identified as core members of the microbiome of stony coral Cladocora caespitosa 81 , and appear in the microbiomes of corals worldwide 19 , 21 , 22 , 35 – 37 , 41 , 42 , 45 , 54 , 63 – 65 , 71 , 76 , 82 – 85 . Though Vibrios are often associated with coral disease, their widespread association with healthy corals suggests an important function in the normal functioning of the coral holobiont.…”

Spatial and Seasonal Variability of Reef Bacterial Communities in the Upper Gulf of Thailand

“…Similarly, the predominant orders Pseudomonadales (genus Psychrobacter) and Oceanospiralles (Cobetia and Endozoicomonas) likely benefit the corals. Psychrobacter supports the metabolism of complex carbohydrates, amino acids, and lipids, and were reported in abundance in the mucus of Acropora and Porites (McKew et al, 2012;Badhai et al, 2016). For members of Oceanospiralles, interactions with corals remain unclear, although they have been reported as relatively abundant in tropical reefs.…”

“…Functions such as DNA replication and repair, transcription, translation, energy metabolism, or the incorporation of key cofactors and vitamins are also important for coping with abiotic pressures, such as parasites, heavy metal contamination, ultraviolet radiation, exposure to reactive oxygen, etc. (Tout et al, 2014;Ainsworth et al, 2015;Badhai et al, 2016). COGs involved in cellular processes and signaling (i.e., chemotaxis, two-component system response), membrane transport, signal transduction, and cell motility (Figure 7B), might facilitate cellular interactions and metabolic exchanges between the bacterial community and the coral host (Tout et al, 2014;Ainsworth et al, 2015).…”