The Starlet Sea Anemone, Nematostella vectensis, possesses body region-specific bacterial associations with spirochetes dominating the capitulum

Abstract

Sampling of different body regions can reveal highly specialized bacterial associations within the holobiont and facilitate identification of core microbial symbionts that would otherwise be overlooked by bulk sampling methods. Here, we characterized compartment-specific associations present within the model cnidarian Nematostella vectensis by dividing its morphology into three distinct microhabitats. This sampling design allowed us to uncover a capitulum-specific dominance of spirochetes within N. vectensis. Bacteria from the family Spirochaetaceae made up 66% of the community in the capitulum, while only representing 1.2% and 0.1% of the communities in the mesenteries and physa, respectively. A phylogenetic analysis of the predominant spirochete sequence recovered from N. vectensis showed a close relation to spirochetes previously recovered from wild N. vectensis. These sequences clustered closer to the recently described genus Oceanispirochaeta, rather than Spirochaeta perfilievii, supporting them as members of this clade. This suggests a prevalent and yet uncharacterized association between N. vectensis and spirochetes from the order Spirochaetales.

Anthony Bonacolta

PhD Student · Now Postdoctoral Fellow at The University of British Columbia

My PhD research focused on understanding the roles of micro-eukaryotes and bacteria in marine organisms, including the coral holobiont during bleaching from a single-cell perspective.

Javier del Campo

Group Leader

My research aims at understanding the global diversity and distribution of eukaryotic and prokaryotic microbes employing curated phylogenetic frameworks focusing on novel environmental taxa.