The impact of depuration on mussel hepatopancreas bacteriome composition and predicted metagenome

Abstract

Due to the rapid elimination of bacteria through normal behaviour of filter feeding and excretion, the decontamination of hazardous contaminating bacteria from shellfish is performed by depuration. This process, under conditions that maximize shellfish filtering activity, is a useful method to eliminate microorganisms from bivalves. The microbiota composition in bivalves reflects that of the environment of harvesting waters, so quite different bacteriomes would be expected in shellfish collected in different locations. Bacterial accumulation within molluscan shellfish occurs primarily in the hepatopancreas. In order to assess the effect of the depuration process on these different bacteriomes, in this work we used 16S RNA pyrosequencing and metagenome prediction to assess the impact of 15 h of depuration on the whole hepatopancreas bacteriome of mussels collected in three different locations.

E. coli Is a Poor End-Product Criterion for Assessing the General Microbial Risk Posed From Consuming Norovirus Contaminated Shellfish

“…This also has parallels with humans where E. coli O157:H7 is known to cause disease in humans via preferential binding to the epithelial cells in the gut due to its high abundance of adhesins and fimbriae (Torres et al, 2005;Vidal et al, 2007). Our result is also consistent with the findings that depuration has a major effect on the bacterial diversity within mussel tissues, preferentially retaining some bacteria at the expense of others (Rubiolo et al, 2018).…”

Vibrio splendidus infection induces dysbiosis in the blue mussel and favors pathobiontic bacteria

“…Firmicutes, Planctomycetes, Bacteroidetes Actinobacteria, Verrucomicrobia, Tenericutes and Chloroflexi appeared as subdominant phyla with a relative abundance ranging from 7.1% to 1.3%. The presence of these microbial phyla is common in marine bivalves such as oysters (King et al, 2012;Lokmer et al, 2016) and mussels (Musella et al, 2020;Pierce and Ward, 2019;Rubiolo et al, 2018). However, the prevalence and pattern of dominant bacteria are difficult to compare across studies, especially at lower taxonomic levels, as the structure and the composition of the microbiota is particularly influenced by host factors (genetics, life stages, health status) and harvesting environments (ecology and geography, season) (Paillard et al, 2022).…”

“…However, the prevalence and pattern of dominant bacteria are difficult to compare across studies, especially at lower taxonomic levels, as the structure and the composition of the microbiota is particularly influenced by host factors (genetics, life stages, health status) and harvesting environments (ecology and geography, season) (Paillard et al, 2022). Indeed, previous research has revealed the change in microbiota composition in mussels by different factors such as diet, temperature (Li et al, 2019b(Li et al, , 2018, season (Pierce and Ward, 2019) and depuration (Rubiolo et al, 2018;Vezzulli et al, 2018). Moreover, Musella et al (2020) showed the variability of microbial communities in Mytilus galloprovincialis between the digestive gland, foot, gill, stomach and hemolymph.…”

From the raw bar to the bench: Bivalves as models for human health

“…Increased understanding of microbe-host interactions would also allow developing and/or optimizing strategies to manipulate bivalve microbiome and to prevent/treat the accumulation of human pathogens. Two studies on changes in the composition of the microbiome of mussels after depuration have revealed a decrease in bacterial diversity and evenness, but the studies differ on the outcome regarding changes in the relative abundance of Proteobacteria (Rubiolo et al, 2018;Vezzulli et al, 2018).…”