Imaging the uptake of nitrogen-fixing bacteria into larvae of the coral Acropora millepora
|Author(s)||Lema Anais Kimberley1, 2, 3, 4, 5, Clode Peta L.6, 7, Kilburn Matt R.6, Thornton Ruth8, Willis Bette L.1, 2, 4, Bourne David G.3, 4|
|Affiliation(s)||1 : James Cook Univ, ARC Ctr Excellence Coral Reef Studies, Townsville, Qld 4811, Australia.
2 : James Cook Univ, Coll Marine & Environm Sci, Townsville, Qld 4811, Australia.
3 : Australian Inst Marine Sci, Ctr Marine Microbiol & Genet, PMB 3, Townsville, Qld 4810, Australia.
4 : James Cook Univ, AIMS JCU, Townsville, Qld 4811, Australia.
5 : IFREMER, Dyneco Pelagos, Plouzane, France.
6 : Univ Western Australia, Ctr Microscopy Characterisat & Anal, Crawley, WA, Australia.
7 : Univ Western Australia, Oceans Inst, Crawley, WA, Australia.
8 : Univ Western Australia, Sch Paediat & Child Heath, Crawley, WA, Australia.
|Source||Isme Journal (1751-7362) (Nature Publishing Group), 2016-07 , Vol. 10 , N. 7 , P. 1804-1808|
|WOS© Times Cited||25|
Diazotrophic bacteria are instrumental in generating biologically usable forms of nitrogen by converting abundant dinitrogen gas (N-2) into available forms, such as ammonium. Although nitrogen is crucial for coral growth, direct observation of associations between diazotrophs and corals has previously been elusive. We applied fluorescence in situ hybridization (FISH) and nanoscale secondary ion mass spectrometry to observe the uptake of N-15-enriched diazotrophic Vibrio sp. isolated from Acropora millepora into conspecific coral larvae. Incorporation of Vibrio sp. cells was observed in coral larvae after 4-h incubation with enriched bacteria. Uptake was restricted to the aboral epidermis of larvae, where Vibrio cells clustered in elongated aggregations. Other bacterial associates were also observed in epidermal areas in FISH analyses. Although the fate and role of these bacteria requires additional investigation, this study describes a powerful approach to further explore cell associations and nutritional pathways in the early life stages of the coral holobiont.