Top-Down Proteomic Identification of Shiga Toxin 2 Subtypes from Shiga Toxin-Producing Escherichia coli by Matrix-Assisted Laser Desorption Ionization–Tandem Time of Flight Mass Spectrometry
Workflow for in silico database (ISDB) construction using USDA ISDB Processor v1.2 (Fig. S1) and an unrooted radial phylogenetic tree of the Stx2a, Stx2c, and Stx2d subtypes (Fig. S2).