Trait-Based Comparison of Coral and Sponge Microbiomes

Area of Science:

• Marine microbiology
• Symbiosis research
• Metagenomics and metatranscriptomics

Background:

• Microbial communities are crucial for coral and sponge health and function.
• While microbiome diversity is known, functional roles remain less understood.
• Uncertainty exists regarding functional convergence versus divergence in invertebrate microbiomes.

Purpose of the Study:

• To compare the functional roles of microbiomes in two distinct invertebrate hosts: a coral and a sponge.
• To investigate whether host phylogeny and microhabitat differences shape functionally distinct microbial communities.
• To determine if symbiotic invertebrate hosts harbor functionally similar or dissimilar microbiomes.

Main Methods:

• Utilized metatranscriptomic and 16S rRNA gene profiling.
• Compared microbial communities from a star coral (Montastraea cavernosa) and a giant barrel sponge (Xestospongia muta).
• Analyzed functional pathways related to carbon, nitrogen, and sulfur assimilation, and aerobic nitrogen cycling.

Main Results:

• Identified functional similarities in carbon, nitrogen, and sulfur assimilation and aerobic nitrogen cycling between coral and sponge microbiomes.
• Observed minimal statistical differences in pathway coverage and abundance between the two hosts.
• Noted specific pathway enrichments: phosphonate and siderophore metabolism in coral, chloroalkane metabolism in sponge; carbon fixation in coral, fatty acid metabolism in sponge.

Conclusions:

• Coral and sponge microbiomes exhibit conserved functions in essential metabolic pathways despite taxonomic differences.
• Some specialized metabolic functions may be unique to each host type.
• Metatranscriptomic and metagenomic data showed high correlation, validating functional predictions.