Tolerant sponges might adapt using their microbiome

Increased carbon emissions have been associated with ocean acidification, which could be disastrous for many species. Botté et al take advantage of a natural CO2 seep to investigate the impacts of ocean acidification. They looked at two species of sponge; the more low-pH tolerant Coelocarteria singaporensis (more abundant at the seep site) and the more sensitive Stylissa flabelliformis (more abundant at the control site). The metagenome of samples taken from 3 individuals of each species from both the control and seep sites were sequenced; this was used to determine microbiome community structure and was also functionally annotated. They observed both differences in community structure and differences in functional genes between the 4 treatments. Bacteria associated with C singaporensis had an enhanced potential for efficient carbon and nitrogen metabolism, whereas those associated with S flabelliformis showed a loss of functional potential in more acidic waters. This suggests that the more tolerant C singaporensis makes use of microbiome mediated adaptation- a rapid technique which could help species in a changing climate. This also continues to demonstrate the importance of the microbiome to the health of the host. Overall, this is a useful study with important results that help to explain the ability of an organism to thrive where others do not. However, the use of two-species comparison could limit the scope of the results.

Reference: Botté E, Nielsen S, Wahab M, Webster J, Robbins S, Thomas T, Webster N, 2019, Changes in metabolic potential of the sponge microbiome under ocean acidification, nature communications (10:4134)