Sam F.Y. Li
National University of Singapore, Singapore
Title: NMR and MS-based Metabolomics of Microcystis spp. Unravel the Involvement of Microcystin in Thylakoid Membrane Stabilization and Photoinhibition Resistance
Biography
Biography: Sam F.Y. Li
Abstract
Microcystin (MC), a potent hepatotoxin commonly produced by several freshwater cyanobacterial species, especially Microcystis, pose serious threats to water safety worldwide, making them unsuitable for recreational uses, as well as drinking water supplies. Here, the metabolomes of MC-producing and MC-free Microcystis species chronically exposed to strong light illumination were compared using complementary metabolomics tools; NMR and LC-MS. NMR and MS-based metabolomics were capable of revealing MC-influenced metabolic changes in Microcystis spp. The up-regulation of thylakoid membrane building blocks (phosphotidylglycerol), photosynthetic pigments (chlorophyll-a), and carbon reserve sources (sucrose, glycogen, 3-hydroxybutyreate) in toxic Microcystis strains, indicated the involvement of MC in photosynthesis apparatus stabilization under high light illumination. The lowered levels of intermediates involved in phospholipid degradation revealed that Microcystis strains were more resistant to light-induced oxidative stress in the presence of MC. Taken together, our comparative metabolomic data suggest a photoinhibition resistance role for MC in light-stressed Microcystis spp., and confirm its involvement in thylakoid membrane and chlorophyll-a stabilization..