A synthesis of new, bi-labeled peptides for quantitative proteomics.

Abstract

The reported method allows for a cheap and efficient synthesis of peptides labeled with heavy isotopes, and for their precise quantification. Peptides of our design are stable, and the isotopic label, which is a part of the peptide backbone, is stable as well. Moreover, they can be quickly quantified in solution at any time, so the possible decomposition of standard or a non-uniform distribution of the peptide in lyophylisate does not pose a problem. Therefore, we deem our synthesis to be useful for a broad range of quantitative proteomics methods. In addition, the procedure described herein allows direct application of crude peptides as the analytical standards. The elimination of expensive and time-consuming chromatographic purification reduces the cost of AQUA peptides and gives the possibility of a rapid preparation of large libraries of proteolytic fragments.