The chemical cue tetrabromopyrrole from a biofilm bacterium induces settlement of multiple Caribbean corals.
Microbial biofilms induce larval settlement for some invertebrates, including corals; however, the chemical cues involved have rarely been identified. Here, we demonstrate the role of microbial biofilms in inducing larval settlement with the Caribbean coral Porites astreoides and report the first instance of a chemical cue isolated from a marine biofilm bacterium that induces complete settlement (attachment and metamorphosis) of Caribbean coral larvae. Larvae settled in response to natural biofilms, and the response was eliminated when biofilms were treated with antibiotics. A similar settlement response was elicited by monospecific biofilms of a single bacterial strain, Pseudoalteromonas sp. PS5, isolated from the surface biofilm of a crustose coralline alga. The activity of Pseudoalteromonas sp. PS5 was attributed to the production of a single compound, tetrabromopyrrole (TBP), which has been shown previously to induce metamorphosis without attachment in Pacific acroporid corals. In addition to inducing settlement of brooded larvae (P. astreoides), TBP also induced larval settlement for two broadcast-spawning species, Orbicella (formerly Montastraea) franksi and Acropora palmata, indicating that this compound may have widespread importance among Caribbean coral species.
Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Ft. Pierce, FL 34949, USA sneedj@si.edu.
Jennifer M
JM
Sneed
Eckerd College, 4200 54th Avenue South, St. Petersburg, FL 33711, USA.
Koty H
KH
Sharp
Mote Marine Laboratory and Aquarium, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
Kimberly B
KB
Ritchie
Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Ft. Pierce, FL 34949, USA.
Valerie J
VJ
Paul
D000818:Animals; D037421:Anthozoa / Q000254:growth & development / Q000502:physiology*; D018441:Biofilms; D003463:Cues; D005431:Florida; D007814:Larva / Q000254:growth & development / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy; D008675:Metamorphosis, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D031161:Pseudoalteromonas / Q000737:chemistry* / Q000502:physiology*; D011758:Pyrroles / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
D011758:Pyrroles; D012336:RNA, Ribosomal, 16S
Pseudoalteromonas; biofilm; chemical ecology; coral recruitment; larval settlement