Toxicological effects of CdSe nanocrystals on the marine diatom Phaeodactylum tricornutum: The first mass spectrometry-based proteomic approach.

Fiche publication


Date publication

mai 2018

Journal

Ecotoxicology and environmental safety

Auteurs

Membres identifiés du Cancéropôle Est :
Mr HAMMANN Philippe


Tous les auteurs :
Poirier I, Pallud M, Kuhn L, Hammann P, Demortière A, Jamali A, Chicher J, Caplat C, Gallon RK, Bertrand M

Résumé

In the marine environment, benthic diatoms from estuarine and coastal sediments are among the first targets of nanoparticle pollution whose potential toxicity on marine organisms is still largely unknown. It is therefore relevant to improve our knowledge of interactions between these new pollutants and microalgae, the key players in the control of marine resources. In this study, the response of P. tricornutum to CdSe nanocrystals (CdSe NPs) of 5 nm (NP5) and 12 nm (NP12) in diameter was evaluated through microscopic, physiological, biochemical and proteomic approaches. NP5 and NP12 affected cell growth but oxygen production was only slightly decreased by NP5 after 1-d incubation time. In our experimental conditions, a high CdSe NP dissolution was observed during the first day of culture, leading to Cd bioaccumulation and oxidative stress, particularly with NP12. However, after a 7-day incubation time, proteomic analysis highlighted that P. tricornutum responded to CdSe NP toxicity by regulating numerous proteins involved in protection against oxidative stress, cellular redox homeostasis, Ca regulation and signalling, S-nitrosylation and S-glutathionylation processes and cell damage repair. These proteome changes allowed algae cells to regulate their intracellular ROS level in contaminated cultures. P. tricornutum was also capable to control its intracellular Cd concentration at a sufficiently low level to preserve its growth. To our knowledge, this is the first work allowing the identification of proteins differentially expressed by P. tricornutum subjected to NPs and thus the understanding of some molecular pathways involved in its cellular response to nanoparticles.

Mots clés

Marine microalgae, Nanoparticles, Oxidative stress, Physiological responses, Proteomics, Toxicity

Référence

Ecotoxicol. Environ. Saf.. 2018 May 15;152:78-90