Accurate determination of Peptide Phosphorylation Stoichiometry Via Automated Diagonal Capillary Electrophoresis Coupled with Mass Spectrometry – Proof of Principle

摘要: While reversible protein phosphorylation plays an important role in many cellular processes, simple and reliable measurement of the stoichiometry can be challenging. This is confounded by differences ionization efficiency phosphorylated unphosphorylated sites during analysis mass spectrometry. Here, we demonstrate diagonal capillary electrophoresis–mass spectrometry for accurate determination this stoichiometry. Diagonal electrophoresis a two-dimensional separation method that incorporates immobilized alkaline phosphatase microreactor at distal end first employs identical electrophoretic modes both dimensions. The dimension used to separate mixture forms peptide. Fractions are parked reactor where they undergo complete dephosphorylation. products then periodically transferred second analyzed spec...