Tolerance and detoxification mechanisms in marine diatom Phaeodactylum tricornutum exposed to cadmium

Abstract

Tolerance is one of the most important mechanisms for survival. Organisms living in polluted environments with heavy metals develop tolerance to these contaminants; this tolerance has been attributed to the ability to synthesize metal-binding substances or another different mechanism able to mediate metal detoxification. It has been demonstrated that high levels of metals induce the formation of these substances in plants, algae, and some fungi (phytochelatins), which are a protective mechanism against the toxicity of heavy metals. In this study we have addressed the capacity of the microalga Phaeodactylum tricornutum to produce metal-binding pep tides in response to stress induced by cadmium. Liquid chromatography using biogel P-60, thiol analysis in chromatographic fractions, and capillary electrophoresis provided evidence of phytochelatins production in this alga.