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Looking Outwards: Isolation of Cyanobacterial Released Carbohydrate Polymers and Proteins
Published on: May 27, 2019
Subcellular Localization of Carotenoid Biosynthesis in Synechocystis sp. PCC 6803
Lifang Zhang1, Tiago Toscano Selão1, Eva Selstam2
1School of Biological Sciences, Nanyang Technological University, Singapore.
Abstract:
The biosynthesis pathway of carotenoids in cyanobacteria is partly described. However, the subcellular localization of individual steps is so far unknown. Carotenoid analysis of different membrane subfractions in Synechocystis sp. PCC6803 shows that "light" plasma membranes have a high carotenoid/protein ratio, when compared to "heavier" plasma membranes or thylakoids. The localization of CrtQ and CrtO, two well-defined carotenoid synthesis pathway enzymes in Synechocystis, was studied by epitope tagging and western blots. Both enzymes are locally more abundant in plasma membranes than in thylakoids, implying that the plasma membrane has higher synthesis rates of β-carotene precursor molecules and echinenone.
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