Mass spectrometric determination of disulfide linkages in recombinant therapeutic proteins using online LC-MS with electron-transfer dissociation.

ABSTRACT: In the biotechnology industry, the generation of incorrectly folded recombinant proteins, either from an E.coli expression system or from an overexpressed CHO cell line (disulfide scrambling), is often a great concern as such incorrectly folded forms may not be completely removed in the final product. Thus, significant efforts have been devoted to map disulfide bonds to ensure drug quality. Similar to ECD, disulfide bond cleavages are preferred over peptide backbone fragmentation in ETD. Thus, an online LC-MS strategy combining collision-induced dissociation (CID-MS(2)), electron-transfer dissociation (ETD-MS(2)), and CID of an isolated product ion derived from ETD (MS(3)) has been used to characterize disulfide-linked peptides. Disulfide-linked peptide ions were identified by CID and ETD

SUBMITTER: Wu SL 

PROVIDER: S-EPMC2645030 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature