Improving the efficacy of sewage treatment decreases norovirus contamination in oysters.

As human population increases worldwide, water quality will become increasingly problematic, and food consumed raw may be of higher risk. This is already evident for oysters grown in coastal areas - despite regulations based on bacterial indicators, oysters are still implicated in food-borne outbreaks worldwide. The pathogens most frequently detected are human noroviruses, which are shed at high concentrations in human excreta and are very resistant to environmental conditions.

Different secretory repertoires control the biomineralization processes of prism and nacre deposition of the pearl oyster shell.

Mollusca evolutionary success can be attributed partly to their efficiency to sustain and protect their soft body with an external biomineralized structure, the shell. Current knowledge of the protein set responsible for the formation of the shell microstructural polymorphism and unique properties remains largely patchy. In Pinctada margaritifera and Pinctada maxima, we identified 80 shell matrix proteins, among which 66 are entirely unique.

Transcriptome and proteome analysis of Pinctada margaritifera calcifying mantle and shell: focus on biomineralization.

Background: The shell of the pearl-producing bivalve Pinctada margaritifera is composed of an organic cell-free matrix that plays a key role in the dynamic process of biologically-controlled biomineralization. In order to increase genomic resources and identify shell matrix proteins implicated in biomineralization in P. margaritifera, high-throughput Expressed Sequence Tag (EST) pyrosequencing was undertaken on the calcifying mantle, combined with a proteomic analysis of the shell.

Molecular detection of the oyster parasite Mikrocytos mackini, and a preliminary phylogenetic analysis.

The protistan parasite Mikrocytos mackini, the causative agent of Denman Island disease in the oyster Crassostrea gigas in British Columbia, Canada, is of wide concern because it can infect other oyster species and because its life cycle, mode of transmission, and origins are unknown. PCR and fluorescent in situ hybridization (FISH) assays were developed for M. mackini, the PCR assay was validated against standard histopathological diagnosis, and a preliminary phylogenetic analysis of the M.

Changes in circulating and tissue-infiltrating hemocyte parameters of European flat oysters, Ostrea edulis, naturally infected with Bonamia ostreae.

We assayed European flat oyster, Ostrea edulis, hemocyte parameters, circulating and tissue-infiltrating hemocyte densities, circulating hemocyte type distribution and lysosomal enzyme contents, to possibly relate these hematological parameters to Bonamia ostreae infection. Circulating hemocyte densities were not statistically different between infected and uninfected oysters. In contrast, the number of tissue-infiltrating hemocytes increased with infection intensity suggesting a recruitment process at the site of infection and a possibility for cells to migrate from circulatory system to connective tissues.