Primary amine coding as a path to comparative proteomics

Abstract

Various isotope coding strategies are being used today in the field of comparative proteomics. This article specifically reviews the strengths and limitations of various N‐termini‐directing strategies. N‐termini‐directed coding strategy allows for use of different chromatographic enrichment techniques. Since N‐termini‐directed coding strategies are global in nature, they can be utilized in studying PTMs as well as protein expression. Using different N‐termini‐directed coding strategies, both relative and absolute quantification of proteins can be achieved either in the MS mode or in the MS/MS mode. The review ends with the conclusion that significant improvements have been made in the last decade. Among various issues, a need still exists for a better understanding of the kinetic issues in proteomics, relative protein pool sizes for different proteins and the issue of stimulus‐induced changes in protein aggregation. Another critical issue that needs to be addressed in great detail is the role of PTMs in regulation.