Title Application of Free-Flow Electrophoresis/2-Dimentional Gel Electrophoresis for Fractionation and Characterization of Native Proteome of Pseudomonas putida KT2440
Author Chi-Won Choi1, Young S. Hong2, and Seung Il Kim1*
Address 1Proteome Research Team, Korea Basic Science Institute, Daejeon 305-806, Republic of Korea, 2Department of Tropical Medicine, Tulane University, 1430 Tulane Avenue, New Orleans, LA 70112, USA
Bibliography Journal of Microbiology, 46(4),448-455, 2008,
DOI
Key Words free flow electrophoresis, native proteome fractionation, Pseudomonas putida KT2440
Abstract Free Flow Electrophoresis (FFE) is a liquid-based isoelectric focusing method. Unlike conventional in-gel fractionation of proteins, FFE can resolve proteins in their native forms and fractionation of subcellular compartments of the cell is also possible. To test the efficacy of the FFE method, the native cytosol proteome of a bacterium, Pseudomonas putida KT2440 was fractionated by FFE and the spectrum of protein elutes was characterized in association with 2-dimentional gel electrophoresis (2-DE). Major native proteins of P. putida KT2440 were eluted in the range of pH 4.8~6.0 in FFE, whereas the denatured proteome of P. putida KT2440 was widely distributed in the rage of pH 4~10 in the 2-DE analysis. In addition, one of the three FFE major fractions, which was eluted at pH 5.0, was further analyzed using 2-DE/MS-MS. Then, the pH range of identified proteins eluted in 2-DE/MS-MS was 4.72~5.89, indicating that observed pI values of native cytosolic proteomes in FFE were narrower than those of denatured cytosolic proteome. These results suggest that FFE fractionation and 2-DE/MS analysis may be useful tools for characterization of native proteomes of P. putida KT2440 and comparative analysis between denatured and native proteomes.