UNIT 23.4 Quantitative Protein Analysis Using Enzymatic [18O]Water Labeling
Published Online: 1 APR 2014
Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.
Lab Protocol Title
Current Protocols in Protein Science
How to Cite
Castillo, M. J., Reynolds, K. J., Gomes, A., Fenselau, C. and Yao, X. 2014. Quantitative Protein Analysis Using Enzymatic [18O]Water Labeling. Current Protocols in Protein Science. 76:23.4:23.4.1–23.4.9.
- Published Online: 1 APR 2014
This unit describes the stepwise procedure for differential oxygen isotope labeling of peptides and mass spectrometric quantification of relative protein levels in comparative proteomic experiments. The [18O] labeling of peptides happens at the peptide C-terminus and is achieved via the enzymatic oxygen exchange of tryptic peptides via catalysis of immobilized trypsin. Experimental considerations in effective incorporation and stabilization of the oxygen labels are discussed. Methods for mass spectrometric quantification of peptides with differential [16O] and [18O] isotopes are presented. Curr. Protoc. Protein Sci. 76:23.4.1-23.4.9. © 2014 by John Wiley & Sons, Inc.
- enzymatic oxygen labeling;
- quantitative proteomics;
- immobilized trypsin;