Improved Peptide Mapping of Therapeutic Antibodies using Proteases with Orthogonal Cleavage Specificity

Part # PS321

Abstract

Chris Hosfield, Michael Rosenblatt and Marjeta Urh
Promega Corporation, 2800 Woods Hollow Rd, Madison, WI 53711

Peptide mapping of therapeutic proteins is typically performed with trypsin. While trypsin is an excellent protease, peptide maps produced with trypsin are not always complete and tryptic peptides may not be suitable to monitor all important quality attributes. In such cases, using alternative proteases with orthogonal sequence coverage can help fill these gaps. In this study we report the characterization of a new recombinant Asp-specific protease, rAsp-N, and utilized the NISTmAb reference IgG to develop protocols for efficient digestion and improved sequence coverage compared to trypsin alone. We further illustrate how sequence coverage can be increased within a single injection by combining digests from both proteases prior to data collection.

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