Top-down proteomic identification of plasmid and host proteins produced by pathogenic Escherichia coli using MALDI-TOF-TOF tandem mass spectrometry.

ABSTRACT: Fourteen proteins produced by three pathogenic Escherichia coli strains were identified using antibiotic induction, MALDI-TOF-TOF tandem mass spectrometry (MS/MS) and top-down proteomic analysis using software developed in-house. Host proteins as well as plasmid proteins were identified. Mature, intact protein ions were fragmented by post-source decay (PSD), and prominent fragment ions resulted from the aspartic acid effect fragmentation mechanism wherein polypeptide backbone cleavage (PBC) occurs on the C-terminal side of aspartic acid (D), glutamic acid (E) and asparagine (N) residues. These highly specific MS/MS-PSD fragment ions were compared to b- and y-type fragment ions on the C-terminal side of D-, E- and N-residues of in silico protein sequences derived from whole genome sequencin

SUBMITTER: Fagerquist CK 

PROVIDER: S-EPMC8629258 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature