Data_Sheet_1_Highly Variable and Non-complex Diazotroph Communities in Corals From Ambient and High CO2 Environments.pdf

• Main Authors: Laura Geissler, Valentine Meunier, Nils Rädecker, Gabriela Perna, Riccardo Rodolfo-Metalpa, Fanny Houlbrèque, Christian R. Voolstra
• Format: Dataset
• Language: unknown
• Published: 2021
• Subjects: Oceanography; Marine Biology; Marine Geoscience; Biological Oceanography; Chemical Oceanography; Physical Oceanography; Marine Engineering; coral holobiont; diazotrophy; nitrogen fixation; climate change; ocean acidification; nifH; next-generation sequencing; Rus’; Ocean acidification
• Online Access: https://doi.org/10.3389/fmars.2021.754682.s001; https://figshare.com/articles/dataset/Data_Sheet_1_Highly_Variable_and_Non-complex_Diazotroph_Communities_in_Corals_From_Ambient_and_High_CO2_Environments_pdf/16894078

The ecological success of corals depends on their association with microalgae and a diverse bacterial assemblage. Ocean acidification (OA), among other stressors, threatens to impair host-microbial metabolic interactions that underlie coral holobiont functioning. Volcanic CO 2 seeps offer a unique opportunity to study the effects of OA in natural reef settings and provide insight into the long-term adaptations under a low pH environment. Here we compared nitrogen-fixing bacteria (diazotrophs) associated with four coral species (Pocillopora damicornis, Galaxea fascicularis, Acropora secale, and Porites rus) collected from CO 2 seeps at Tutum Bay (Papua New Guinea) with those from a nearby ambient CO 2 site using nifH amplicon sequencing to characterize the effects of seawater pH on bacterial communities and nitrogen cycling. Diazotroph communities were of generally low diversity across all coral species and for both sampling sites. Out of a total of 25 identified diazotroph taxa, 14 were associated with P. damicornis, of which 9 were shared across coral species. None of the diazotroph taxa, however, were consistently found across all coral species or across all samples within a species pointing to a high degree of diazotroph community variability. Rather, the majority of sampled colonies were dominated by one or two diazotroph taxa of high relative abundance. Pocillopora damicornis and Galaxea fascicularis that were sampled in both environments showed contrasting community assemblages between sites. In P. damicornis, Gammaproteobacteria and Cyanobacteria were prevalent under ambient pCO 2 , while a single member of the family Rhodobacteraceae was present at high relative abundance at the high pCO 2 site. Conversely, in G. fascicularis diazotroph communities were indifferent between both sites. Diazotroph community changes in response to OA seem thus variable within as well as between host species, potentially arguing for haphazard diazotroph community assembly. This warrants further research into the underlying ...