Comparative proteomics exploring the molecular mechanism of eutrophic water purification using water hyacinth (Eichhornia crassipes)

Eutrophication is a serious threat to ecosystem stability and use of water resources worldwide. Accordingly, physical, chemical, and biological technologies have been developed to treat eutrophic water. Phytoremediation has attracted a great deal of attention, and water hyacinth (Eichhornia crassipes) is regarded as one of the best plants for purification of eutrophic water. Previous studies have shown that water hyacinths remove nitrogen (N) and phosphorus (P) via diverse processes and that they can inhibit the growth of algae. However, the molecular mechanisms responsible for these processes, especially the role of proteins, are unknown. In this study, we applied a proteomics approach to investigate the protein dynamics of water hyacinth under three eutrophication levels. The results suggested that proteins with various functions, including response to stress, N and P metabolic pathways, synthesis and secretion, photosynthesis, biosynthesis, and energy metabolism, were involved in regulating water hyacinth to endure the excess-nutrient environment, remove N and P, and inhibit algal growth. The results help us understand the mechanism of purification of eutrophic water by water hyacinth and supply a theoretical basis for improving techniques for phytoremediation of polluted water.