title: Trophic Mode-Dependent Proteomic Analysis Reveals Functional Significance of Light-Independent Chlorophyll Synthesis in Synechocystis sp. PCC 6803.
abstract: The photosynthetic model organism Synechocystis sp. PCC 6803 can grow in different trophic modes, depending on the availability of light and exogenous organic carbon source. However, how the protein profile changes to facilitate the cells differentially propagate in different modes has not been comprehensively investigated. Using isobaric labeling-based quantitative proteomics, we simultaneously identified and quantified 45% Synechocystis proteome across four different trophic modes, i.e., autotrophic, heterotrophic, photoheterotrophic, and mixotrophic modes. Among the 155 proteins that are differentially expressed across four trophic modes, proteins involved in nitrogen assimilation and light-independent chlorophyll synthesis are dramatically upregulated in the mixotrophic mode, concomitant with a dramatic increase of PIIphosphorylation that senses carbon and nitrogen assimilation status. Moreover, functional study using a mutant defective in light-independent chlorophyll synthesis revealed that this pathway is important for chlorophyll accumulation under a cycled light/dark illumination regime, a condition mimicking day/night cycles in certain natural habitats. Collectively, these results provide the most comprehensive information on trophic mode-dependent protein expression in cyanobacterium, and reveal the functional significance of light-independent chlorophyll synthesis in trophic growth.
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Longfa
authors: L
authors: Fang
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Haitao
authors: H
authors: Ge
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Xiahe
authors: X
authors: Huang
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Ye
authors: Y
authors: Liu
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Min
authors: M
authors: Lu
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Jinlong
authors: J
authors: Wang
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China.
authors: Weiyang
authors: W
authors: Chen
authors: Department of Chemistry, University of Louisiana at Lafayette, Lafayette, LA 70504, USA.
authors: Wu
authors: W
authors: Xu
authors: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Beijing 100101, China. Electronic address: ycwang@genetics.ac.cn.
authors: Yingchun
authors: Y
authors: Wang
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D002734:Chlorophyll / Q000096:biosynthesis* / Q000528:radiation effects; D003624:Darkness; D008027:Light; D010788:Photosynthesis; D052817:Phototrophic Processes; D020543:Proteome; D046939:Synechocystis / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; D002734:Chlorophyll
keywords: Synechocystis; light-independent chlorophyll synthesis; nitrogen assimilation; phosphorylation; proteomics