Changes in the composition and diversity of the bacterial microbiota associated with oysters (Crassostrea corteziensis,Crassostrea gigasandCrassostrea sikamea) during commercial production

Abstract

The resident microbiota of three oyster species (Crassostrea corteziensis, Crassostrea gigas and Crassostrea sikamea) was characterised using a high-throughput sequencing approach (pyrosequencing) that was based on the V3-V5 regions of the 16S rRNA gene. We analysed the changes in the bacterial community beginning with the postlarvae produced in a hatchery, which were later planted at two grow-out cultivation sites until they reached the adult stage. DNA samples from the oysters were amplified, and 31 008 sequences belonging to 13 phyla (including Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes) and 243 genera were generated. Considering all life stages, Proteobacteria was the most abundant phylum, but it showed variations at the genus level between the postlarvae and the adult oysters. Bacteroidetes was the second most common phylum, but it was found in higher abundance in the postlarvae than in adults. The relative abundance showed that the microbiota that was associated with the postlarvae and adults differed substantially, and higher diversity and richness were evident in the postlarvae in comparison with adults of the same species. The site of rearing influenced the bacterial community composition of C. corteziensis and C. sikamea adults. The bacterial groups that were found in these oysters were complex and metabolically versatile, making it difficult to understand the host-bacteria symbiotic relationships; therefore, the physiological and ecological significances of the resident microbiota remain uncertain.

Spatial and Temporal Dynamics of Pacific Oyster Hemolymph Microbiota across Multiple Scales

“…However, these bacteria have been previously found in Pacific oysters in Tasmania (Fernandez-Piquer et al, 2012), suggesting their affinity to form associations with oysters. Both Spirochaetes and Tenericutes are commonly isolated from various oyster tissues (Prieur et al, 1990; Green and Barnes, 2010; Husmann et al, 2010; King et al, 2012; Trabal et al, 2012; Wegner et al, 2013; Trabal Fernandez et al, 2014; Lokmer et al, 2016). However, Spirochaetes and Tenericutes are rare in the hemolymph in the laboratory (Lokmer and Wegner, 2015; Lokmer et al, 2016), where high abundance of Tenericutes is mainly linked to stress or even mortality (Lokmer and Wegner, 2015).…”

“…However, spatial and geographic information has so far primarily served to delineate core microbiomes (e.g., King et al, 2012; Wong et al, 2013; Dishaw et al, 2014) or to differentiate between the microbiomes of closely related species (Zouache et al, 2011; Phillips et al, 2012). This applies especially to marine hosts (e.g., Morrow et al, 2012; Reveillaud et al, 2014; Trabal Fernandez et al, 2014). Studies considering aspects of within-species spatial variation are less common and focused on large-scale differences between environmentally distinct sites (e.g., Trabal et al, 2012; Pierce et al, 2016; Ziegler et al, 2016).…”

Effect of freshwater mussels on the vertical distribution of anaerobic ammonia oxidizers and other nitrogen-transforming microorganisms in upper Mississippi river sediment

“…Numerous studies have found Proteobacteria to be the most abundant phylum in freshwater sediments (Bucci et al, 2014; Dai et al, 2016; Wakelin, Colloff & Kookana, 2008; Zeng et al, 2008; Zhang et al, 2015), sediments with mollusks (Fernandez et al, 2014; Lee et al, 2015), and also mollusk microbiomes (Frischer et al, 2000; Neta et al, 2015; Ngangbam et al, 2015; Trabal et al, 2012). Although our results showed Proteobacteria were the most abundant phylum, we observed a decrease in Proteobacteria by 6% and an increase in Nitrospirae by 10% in the presence of mussels.…”

Streptomyceseffect on the bacterial microbiota associated toCrassostrea sikameaoyster

“…; Trabal Fernandez et al . ). A similar tendency of lower species richness in the final control group ( t = 30) with respect to the initial control group ( t = 0) was also observed as estimated by Chao‐1, even though oysters remained as juvenile.…”

“…In a study with different oyster species, Trabal Fernandez et al . () found that Burkholderia and Escherichia / Shigella were the only Proteobacteria omnipresent in the adult stage of C. sikamea in two different cultivation sites and in the postlarvae stage at the rearing hatchery. Although oysters in this study were in their juvenile stage, the core microbiota of C. sikamea from these two independent studies did not share a single genus.…”