Characterizing the bacterial associates of three Caribbean sponges along a gradient from shallow to mesophotic depths

Abstract

Bacteriosponges have been shown to support relatively stable microbial communities across both distance and time, but little is known about the effect of depth on the composition of the associated community. To address this question, we examined the bacterial communities associated with three common Caribbean bacteriosponges collected at the same location over a depth gradient from approximately 10-100 m. The 16S rRNA genes of the associated communities were assessed using terminal restriction fragment length polymorphism and clone library analyses. Our results indicated that the stability and specificity of the associated bacterial communities varied with the host sponge but that each sponge supported a distinct community. Analyses of similarity suggested differences in community composition with depth, but examination of in silico predicted terminal restriction fragments failed to identify bacteria that occurred specifically at particular depths. Plakortis angulospiculatus, Agelas conifera, and Xestospongia muta supported diverse Chloroflexi species, while X. muta appeared to be the only sponge that hosted a cyanobacterial community. Regardless of host sponge, each species maintained a 'core' group of bacterial associates across a depth range with the composition of the remaining community presumably influenced by both biotic and abiotic factors.

Host-specific assembly of sponge-associated prokaryotes at high taxonomic ranks

“…However, Cyanobacteria were only present in the shallow sponges, whereas Crenarchaeota were more dominant in the upper twilight replicates. This adds to the observations that conspecific sponges from habitats with varying environmental factors (e.g., temperature, light, nutrients) can exhibit diverging prokaryotic community compositions to a certain degree 14, 24–26 . Apparently, certain prokaryotic taxa known to be involved in the nitrogen cycle in sponges, such as Nitrosopumilus , Nitrospira 27, 28 , or Synechococcus 29 are unequally distributed between the different depths in this intraspecific comparison.…”

Latitudinal variation in the microbiome of the sponge Ircinia campana correlates with host haplotype but not anti-predatory chemical defense

“…This high degree of host specificity and symbiont stability is reported across broad longitudinal and bathymetric ranges (Erwin et al 2012a, Olson & Gao 2013, Pita et al 2013b,c, Cárdenas et al 2014, Reveillaud et al 2014, temporal scales (Thiel et al 2007, Erwin et al 2012b, Hardoim & Costa 2014 and in response to exposure to sub-lethal temperatures, elevated nutrient levels, and food shortages (Webster et al 2008, Simister et al 2012a,b, Pita et al 2013a. Notable exceptions to these general trends in sponge microbiology also exist, where significant intraspecific variation in symbiont microbial communities has been detected across different habitats (Cleary et al 2013, Weigel & Erwin 2016) and latitudes (Taylor et al 2005, Anderson et al 2010, thus suggesting that host species is not the only factor that determines microbiome composition.…”

Shedding light on an East-Mediterranean mesophotic sponge ground community and the regional sponge fauna

“…Due to its inaccessibility by scuba diving, until recently it was therefore one of the less-studied habitats in the ocean (Lesser et al, 2009). Thus, basic information on the mesophotic sponge communities, including community composition, species depth range, habitat preferences, and species abundance and distribution, are scarce worldwide (Bo et al, 2011;Schönberg et al, 2012;Olson et al, 2013;Slattery et al, 2015). Furthermore, the processes that structure these communities are virtually unknown.…”