Free‐living bacterial communities associated with tubeworm (Ridgeia piscesae) aggregations in contrasting diffuse flow hydrothermal vent habitats at the Main Endeavour Field, Juan de Fuca Ridge

Abstract

We systematically studied free-living bacterial diversity within aggregations of the vestimentiferan tubeworm Ridgeia piscesae sampled from two contrasting flow regimes (High Flow and Low Flow) in the Endeavour Hydrothermal Vents Marine Protected Area (MPA) on the Juan de Fuca Ridge (Northeast Pacific). Eight samples of particulate detritus were recovered from paired tubeworm grabs from four vent sites. Most sequences (454 tag and Sanger methods) were affiliated to the Epsilonproteobacteria, and the sulfur-oxidizing genus Sulfurovum was dominant in all samples. Gammaproteobacteria were also detected, mainly in Low Flow sequence libraries, and were affiliated with known methanotrophs and decomposers. The cooccurrence of sulfur reducers from the Deltaproteobacteria and the Epsilonproteobacteria suggests internal sulfur cycling within these habitats. Other phyla detected included Bacteroidetes, Actinobacteria, Chloroflexi, Firmicutes, Planctomycetes, Verrucomicrobia, and Deinococcus–Thermus. Statistically significant relationships between sequence library composition and habitat type suggest a predictable pattern for High Flow and Low Flow environments. Most sequences significantly more represented in High Flow libraries were related to sulfur and hydrogen oxidizers, while mainly heterotrophic groups were more represented in Low Flow libraries. Differences in temperature, available energy for metabolism, and stability between High Flow and Low Flow habitats potentially explain their distinct bacterial communities.

Differential specificity between closely related corals and abundant Endozoicomonas endosymbionts across global scales

“…These bacteria also frequently associate with other marine organisms, including gorgonians (Correa et al , 2013; La Rivière et al , 2013; Vezzulli et al , 2013; Bayer et al , 2013a; Ransome et al , 2014), ascidians (Dishaw et al , 2014), tube worms (Forget and Juniper, 2013), mollusks (Jensen et al , 2010; Hyun et al , 2014) and fish (Mendoza et al , 2013). Although the sequence-based evidence for Endozoicomonas as a core microbiome member of certain corals is compelling, most studies have used corals from only one geographic location and often methods across studies are not standardized, making comparative analyses difficult.…”

Endozoicomonas genomes reveal functional adaptation and plasticity in bacterial strains symbiotically associated with diverse marine hosts

“…for review14). These bacteria associate with a wide variety of marine hosts, including corals1516171819, and other cnidarians2021, sponges2223, gorgonians242526, molluscs2728, worms29, fish3031, and tunicates3233. Despite these associations with numerous hosts in oceans worldwide, the functional role of Endozoicomonas remains unclear.…”

Ultra-Violet Radiation Has a Limited Impact on Seasonal Differences in the Acropora Muricata Holobiont

“…As the immunocompetence of an animal largely depends on its energy reserves, the higher occurrence of potentially pathogenic OTUs in A. muricata in summer may be linked to a reduced fitness of the holobiont, as evidenced by the lower tissue biomass (proteins), and Symbiodinium photosynthetic efficiency compared to winter. In summer, we also observed a lower abundance of Thalassospira, known as potential symbionts of ctenophores (Hao, 2014), and four OTUs of Endozoicomonas, a genus commonly found in healthy corals (Bayer et al, 2013a,b;Neave et al, 2017;van de Water et al, 2017van de Water et al, , 2018b, as well as in a wide range of other marine invertebrates (Forget and Juniper, 2013;Fiore et al, 2015;Katharios et al, 2015). Although their exact functions are unknown, both Thalassospira and Endozoicomonas may be involved in host health through nutrient acquisition and provision, and in structuring of the host microbial community (Hao, 2014; reviewed by Neave et al, 2016).…”