Biochemical biomarkers protocols in C. gigas and their applications in deep-sea species
Supervisors: Aourell Mauffret Nathalie Wessel Audrey Barranger (IFREMER)
In a context of global anthropisation, the application and development of biochemical biomarker methods and protocols has been an essential step to assess biotic impacts in numerous marine species. Toxicity tests already applied to coastal organisms (such as bivalves) could also be applied in lesser-known, deep-sea organisms. With an effort to address the knowledge gap associated with deep-sea environments, the CHeReef project aims at studying deep-sea corals and associated fauna in the Lampaul canyon, located 200 km away from the coast of Brittany. The third campaign (https://doi.org/10.17600/18003189), deployed on board of the Research Vessel “Pourquoi pas ?” collected a selection of biota from the canyon. Thus, the application of 2 biomarkers of oxidative stress (CAT, GST) and one marker of neurotoxic stress (AChE) has been done in a selection of organisms (the coldwater coral Lophelia pertusa, the annelid worm Eunice norvegica and unidentified crinoid individuals) collected in the survey. Another part of the report, carried on the model organism C. gigas assessed potential effect of time, type of conservation (processed sample or not) and conservation (Snap frozen or not) using the same biomarkers to assess potential damage due to sampling and length of conservation in deep-sea samples. Overall, different treatments in C. gigas samples allowed to see mixed results within enzymatic activities, highly influenced by the organ sampled. Significant effects of time and/or treatment were observed in multiple markers with a decrease of CAT and GST activity in samples stored as processed cytosolic fraction through time. Deep-sea samples showed varied results depending on the species considered in measured protein content, as well as CAT, AChE and GST activities, determining possible baseline values in 3 lesser known, deep-sea organisms.