tailieunhanh - Báo cáo khoa học: Proteomics of Synechocystis sp. PCC 6803 Identification of novel integral plasma membrane proteins

The cyanobacterial plasma membrane is an essential cell barrier with func-tions such as the control of taxis, nutrient uptake and secretion. These functions are carried out by integral membrane proteins, which are difficult to identify using standard proteomic methods. | ỊFEBS Journal Proteomics of Synechocystis sp. PCC 6803 Identification of novel integral plasma membrane proteins Tatiana Pisareva1 Maria Shumskaya1 Gianluca Maddalo2 Leopold Ilag2 and Birgitta Norling1 1 Department of Biochemistry and Biophysics Arrhenius Laboratories for NaturalSciences Stockholm University Sweden 2 Department of AnalyticalChemistry Arrhenius Laboratories for NaturalSciences Stockholm University Sweden Keywords cyanobacteria integral proteins plasma membrane proteome Synechocystis 6803 Correspondence B. Norling Department of Biochemistry and Biophysics Arrhenius Laboratories of Natural Sciences Stockholm University SE-10691 Stockholm Sweden Fax 46 8 153679 Tel 46 8 162460 E-mail birgitta@ Received 8 September 2006 revised 27 November 2006 accepted 5 December 2006 The cyanobacterial plasma membrane is an essential cell barrier with functions such as the control of taxis nutrient uptake and secretion. These functions are carried out by integral membrane proteins which are difficult to identify using standard proteomic methods. In this study integral proteins were enriched from purified plasma membranes of Synechocystis sp. PCC 6803 using urea wash followed by protein resolution in 1D SDS PAGE. In total 51 proteins were identified by peptide mass fingerprinting using MALDI-TOF MS. More than half of the proteins were predicted to be integral with 1-12 transmembrane helices. The majority of the proteins had not been identified previously and include members of metalloproteases chemotaxis proteins secretion proteins as well as type 2 NAD P H dehydrogenase and glycosyltransferase. The obtained results serve as a useful reference for further investigations of the address codes for targeting of integral membrane proteins in cyanobacteria. doi Cyanobacteria are unique among prokaryotes because of their complex membrane organization. Similar to other Gram-negative bacteria cyanobacteria have an envelope consisting of