An important factor dictating coral fitness is the quality of bacteria associated with corals and coral reefs. One way that bacteria benefit corals is by stimulating the larval to juvenile life cycle transition of settlement and metamorphosis. Tetrabromopyrrole (TBP) is a small molecule produced by bacteria that stimulates metamorphosis with and without attachment in a range of coral species. A standing debate remains, however, about whether TBP biosynthesis from live
- Award ID(s):
- 1942251
- NSF-PAR ID:
- 10463819
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- ISME Communications
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2730-6151
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Pseudoalteromonas luteoviolacea is a globally distributed marine bacterium that stimulates the metamorphosis of marine animal larvae, an important bacteria–animal interaction that can promote the recruitment of animals to benthic ecosystems. Recently, differentP .luteoviolacea isolates have been shown to produce two stimulatory factors that can induce tubeworm and coral metamorphosis; Metamorphosis‐Associated Contractile structures (MACs) and tetrabromopyrrole (TBP) respectively. However, it remains unclear what proportion ofP .luteoviolacea isolates possess the genes encoding MACs, and what phenotypic effect MACs and TBP have on other larval species. Here, we show that 9 of 19 sequencedP .luteoviolacea genomes genetically encode both MACs and TBP. WhileP .luteoviolacea biofilms producing MACs stimulate the metamorphosis of the tubewormHydroides elegans , TBP biosynthesis genes had no effect under the conditions tested. Although MACs are lethal to larvae of the cnidarianHydractinia symbiologicarpus ,P .luteoviolacea mutants unable to produce MACs are capable of stimulating metamorphosis. Our findings reveal a hidden complexity of interactions between a single bacterial species, the factors it produces and two species of larvae belonging to different phyla. -
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