Shotgun Label-free Proteomic Analyses of the Oyster Parasite Perkinsus Marinus - Shotgun Label-free Proteomic Analyses of the Oyster Parasite Perkinsus Marinus - Open Access Pub

Perkinsus marinus is an intracellular parasitic protozoan that is responsible for serious disease epizootics in marine bivalve mollusks worldwide. Despite all available information on P. marinus genomics, more baseline data is required at the proteomic level. Our aim was to study the proteome profile of in vitro cultured P. marinus isolated from oysters Crassostrea spp. using a label-free shotgun UDMSE approach. A total of 4073 non-redundant proteins were identified across three biological replicates with stringent identification. Proteins specifically related to adaptive survival, cell recognition, antioxidants, regulation of apoptosis and others were detected. Important virulence factors of P. marinus were identified including serine protease and iron-dependent superoxide dismutase. Other proteins with involvement in several pathogens invasion strategies were rhoptries, serine-threonine kinases, and protein phosphatases. Interestingly, peptides corresponding to retroviruses polyproteins were identified in all replicates. The interactomic analysis of P. marinus proteins demonstrated extensive clusters network related to biological processes. In conclusion, we provide the first comprehensive proteomic profile of P. marinus that can be useful for further investigations on Perkinsus biology and virulence mechanisms. DOI10.14302/issn.2326-0793.JPGR-17-1571 Marine bivalve molluscs production worldwide is being affected by disease epizootics caused by intracellular protozoan parasites of the genus Perkinsus. Numerous species have been described but only two species namely Perkinsusmarinus and Perkinsusolseni require notification to the World Organization for Animal Health 1. P. marinus has been associated with significant mortalities of the eastern oyster Crassostrea virginica but other species such as the pacific oyster Crassostrea gigas and the mangrove oyster Crassostrea rhizophorae are also susceptible 2. The parasite belongs to a new independent phylum Perkinsozoa that is positioned between the phyla Apicomplexa and Dinoflagellata 3. Species of Perkinsus are believed to be transmitted directly from host to host during the feeding process 4. Different developmental stages are observed that are all believed to be infective 2. No effective therapies have been developed to date. A considerable amount of genomic information is availablefor P. marinus. In contrast, few studies available on comparisons of proteomic profiles of different Perkinsus species and on proteome variability of P. olseni resulted in low throughputs: 28 and 19 annotated proteins,