Positional proteomics at the N-terminus as a means of proteome simplification.

One strategy to reduce complexity in proteome analysis is through rational reduction of the proteolytic peptides that constitute the analyte for mass spectrometric analysis. Methods for selective isolation of C- and N-terminal peptides have been developed. In this chapter, we outline the context and variety of methods for selective isolation of N-terminal peptides and detail one method based on negative selection through differential removal of internal peptides.