Andrade, Lidiane Maria, et al. “Chlorella Vulgaris Phycoremediation at Low Cu+2 Contents: Proteomic Profiling of Microalgal Metabolism Related to Fatty Acids and CO2 Fixation.” Chemosphere, Elsevier BV, Dec. 2021, p. 131272. Crossref, doi:10.1016/j.chemosphere.2021.131272.

Abstract

The aim of this work was to correlate metabolic changes with copper ions (Cu⁺²) bioremediation by microalgae C. vulgaris 097 CCMA-UFSCar at low Cu⁺² content. The metabolic effects include proteome changes related to fatty acid biosynthesis (value-added product) and carbon fixation (climate change mitigation). Cu⁺², even at low concentration, showed a significant negative impact on C. vulgaris growth. The microalgal bioremediation reached 100, 74, 38 and 26% for Cu⁺² content at 0.1; 0.3; 0.6 and 0.9 mg L⁻¹, respectively. Regarding proteomics, the numbers of proteins reduced (≈37%) from 581 proteins (control) to 369 proteins (0.9 mg of Cu⁺² L⁻¹) compared to control. The microalgal CO₂ fixation is strictly related to the Calvin cycle, particularly phase 1, in which ribulose bisphosphate carboxylase large chain (RuBisCO) produces two phosphoglycerate molecules from CO₂ and ribulose 1,5-bisphosphate. Then, phosphoglycerate can be metabolically reduced into glucose. When compared to control, the RuBisCO was underexpressed (≈50%). Similar changes in proteomic profiling of metabolism-related to fatty acid biosynthesis was observed. Nevertheless, no protein was found for the cultivation at 0.9 mg of Cu⁺² L⁻¹. Thus, the analysis of C. vulgaris proteomic data indicated that even at low concentration, Cu⁺² lead to drastic metabolic changes.