Proteomic analysis of the cyanobacterium Synechocystis sp. PCC 6803
EMSL Project ID
11104
Abstract
Cyanobacteria are oxygenic photo-autotrophic prokaryotes that are responsible for roughly 50% of the primary productivity in oceans and lakes. Among the oxygenic photosynthetic organisms cyanobacteria are the most ancient. Cyanobacteria are closely related to plant chloroplasts that have developed from a single endosymbiosis event between a eukaryotic cell and a cyanobacterium. Photosynthetic processes in cyanobacteria take place in the specialized thylakoid membranes. In these membranes the photosynthetic electron transport chain, which is responsible for transforming light energy into chemical energy, resides. Being dependent on photosynthesis, cyanobacterial cells are uniquely adapted to harvesting and utilizing light energy under constantly changing environmental conditions. The adaptation mechanisms span the range between increasing the efficacy of light harvesting at low light intensities to protecting the photosynthetic apparatus from photo-oxidative damage under high light intensities. In addition, depending on photosynthetic processes, an increased demand for micronutrients such as iron and manganese and substrates such as CO2 is created. The result of these requirements is that a large fraction of the cyanobacterial genome contains genes which are directly or indirectly involved in photosynthetic processes. The purpose of this proposal is to expand our knowledge on the networks by which these processes are regulated. In order to do so we propose to study the proteome of a well established cyanobacterial model organism, Synechocystis sp. PCC 6803.
For the purpose of this EMSL User project we have grown Synechocystis cells under a variety of culture conditions to generate a diverse set of protein expression profiles. So far, limited proteomic analysis has revealed approximately 1/3 of the Synechocystis proteome. In order to study regulatory networks in Synechocystis we propose to extend the degree of proteomic coverage by analyzing additional growth/stress condition samples by high resolution LC-MS/MS and to do a comparison of the proteins detected between these distinct culture conditions. Limited SCX fractionation will be performed on a selected number of key growth/stress conditions which show the greatest promise following the initial proteome analyses to assist in extending the overall coverage of the Synechocystis proteome.
Project Details
Project type
Exploratory Research
Start Date
2004-10-28
End Date
2005-12-14
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Xu M, T. Ogawa, HB Pakrasi, and H Mi. 2008. Identification and localization of the CupB protein involved in constitutive CO2-uptake in the cyanobacterium, Synechocystis sp. strain PCC 6803. Plant and Cell Physiology 49(6): 994-997