Differential proteomes of the cyanobacterium Cyanothece sp. CCY 0110 upon exposure to heavy metals

The proteomes of the highly efficient extracellular polymeric substances (EPS)-producer cyanobacterium Cyanothece sp. CCY 0110, grown in medium supplemented with an essential metal (Cu2+) or a non-essential metal (Cd2+),were compared using iTRAQ technology. The data were obtained within a larger study that evaluated the overall effects of different heavy metals on growth/survival, EPS production and ultrastructure of this cyanobacterium [1]. To allow a broader understanding of the strategies triggered to coupe with toxic effects of the metals, Cyanothece′s proteomes were evaluated after chronic and acute exposure to Cu2+ and Cd2+ in two independent 8-plex iTRAQ studies. For the chronic exposure 0.1 mg/l of Cu2+ or 5 mg/l of Cd2+ were used for 10 and 20 days, while in the acute experiments the cells were exposed to 10× these concentrations for 24 h. 202 and 268 proteins were identified and quantified for studies 1 (Cu2+) and 2 (Cd2+), respectively. The majority of the proteins with significant fold changes were associated with photosynthesis, CO2 fixation and carbohydrate metabolism, translation, and nitrogen and amino acid metabolism.