A Combined Method of Protein Extraction from Unorthodox Plant Samples for Proteomics

This study aimed to generate an improved method of protein extraction and purification from plant tissues containing very high amounts of phenolic compounds and other interfering biomolecules. Protein extraction at proteomic studies on some plant species including conifers is challenging and the yield and quality is unpredictable. Two popular protocols were combined with each other to construct a novel one with enhanced abilities to produce higher purity of samples compatible for high precision molecular systems and analysis. The new method was compared with the other two for their efficiencies in classical SDS-PAGE, 2-DE and capillary chromatography applications. All three methods were comparable in SDS-PAGE procedure; however, only the new method created acceptable gel images in 2-DE. Bioanalyzer results, also, demonstrated that the new method provided protein samples pure enough to be used in capillary chromatography with 2 times more peaks in electropherograms with lower noise and higher total relative protein concentrations closest to the applied amount. The new combined method is a successful alternative for plant proteomicists with higher yield and quality of proteins from recalcitrant tissues. The new method could be preferred, especially, for high-tech, sensitive proteomic analysis.