, Iodoacetamide reaction with the sulfhydryl group of cysteine side chain. (B) Schematic representation of preRumA * showing five different fragments expected from the tryptic digestion. (C) Charged ions peaks observed in the Orbitrap Fusion nLC-MS spectrum of the digested preRumA * products. The predicted exact masses for each of the fragments are labeled in their respective spectra. (D) MS 2 experiments and assignment of trypsin-activated RumA fragment ion peaks. Major product ions in the spectrum were identified to fit successive loss of Gln18, FIGURE 8 | Iodoacetamide derivatization and trypsin cleavage of preRumA *. (A)

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