Abstract
In shotgun proteomics, peptide fractionation is essential for in-depth characterization of proteomes and the mapping of protein posttranslational modifications. Recently, a mix-mode chromatography [i.e., electrostatic repulsion hydrophilic interaction chromatography (ERLIC)] has been developed and found to be a versatile method in proteome characterization. Here, we use ERLIC to characterize the glycoproteome and phosphoproteome simultaneously. We also demonstrate that the ERLIC can be an alternative to the commonly used strong cation exchange chromatography for higher recovery of proteins during whole proteome analysis. These protocols can be easily adopted in most proteomics laboratories.