Discovery and characterization of a photo-oxidative histidine-histidine cross-link in IgG1 antibody utilizing ¹⁸O-labeling and mass spectrometry.

ABSTRACT: A novel photo-oxidative cross-linking between two histidines (His-His) has been discovered and characterized in an IgG1 antibody via the workflow of XChem-Finder, (18)O labeling and mass spectrometry (Anal. Chem. 2013, 85, 5900-5908). Its structure was elucidated by peptide mapping with multiple proteases with various specificities (e.g., trypsin, Asp-N, and GluC combined with trypsin or Asp-N) and mass spectrometry with complementary fragmentation modes (e.g., collision-induced dissociation (CID) and electron-transfer dissociation (ETD)). Our data indicated that cross-linking occurred across two identical conserved histidine residues on two separate heavy chains in the hinge region, which is highly flexible and solvent accessible. On the basis of model studies with short peptides, it has

SUBMITTER: Liu M 

PROVIDER: S-EPMC4030806 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature