Skip to main content
Fig. 3 | Microbiome

Fig. 3

From: Metagenomic, phylogenetic, and functional characterization of predominant endolithic green sulfur bacteria in the coral Isopora palifera

Fig. 3

Putative pathways and a proposed syntrophic model of dominant bacteria in the green layer. a Putative nitrogen, sulfur, and carbon fixation metabolisms in the green layer. Solid arrows indicate pathways with genes present in the metagenome; dotted arrows indicate pathways with genes not present in the metagenome. Asterisks indicate pathways with genes affiliated to GSB. Colors of arrows indicate different metabolic pathways. b A syntrophic model of dominant GSB and sulfate-reducer in the green layer. GSB are able to obtain light that shines into the coral skeleton. During photosynthesis, GSB obtain CO2 released by sulfate-reducing bacteria (SRB) and other heterotrophs. For carbon fixed by the rTCA cycle, GSB obtain sulfide as an electron donor, which comes from SRB, while the SRB obtain oxidized sulfur compounds released from GSB. Therefore, GSB and SRB provide sulfur resources for each other. Functional redundancy of nitrogen fixation might be present in the coral skeleton because both GSB and SRB could process nitrogen fixation

Back to article page