Agricultural Research Service, U.S. Department of Agriculture 1 article published in JoVE Chemistry Identification of Antibacterial Immunity Proteins in Escherichia coli using MALDI-TOF-TOF-MS/MS and Top-Down Proteomic Analysis Clifton K. Fagerquist1, Ernesto Rojas1 1Produce Safety & Microbiology, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture Here we present a protocol for the rapid identification of proteins produced by genomically sequenced pathogenic bacteria using MALDI-TOF-TOF tandem mass spectrometry and top-down proteomic analysis with software developed in-house. Metastable protein ions fragment because of the aspartic acid effect and this specificity is exploited for protein identification.
