Expressed protein ligation allows for the attachment of a chemically labeled peptide to the N- or C-terminus of a recombinant protein. In this book chapter, the practical considerations involved in using this protein engineering technology are described. In particular, approaches used to design optimal ligation sites are discussed. In addition, several methods used to generate the reactive fragments required for EPL are highlighted in practical details. Finally, strategies that one can implement to achieve efficient ligation reactions are presented.
Keywords: C-terminal thioester; Expressed protein ligation; Ligation site; N-terminal cysteine; Protein chemistry; Protein engineering; Protein labeling; Solid-phase peptide synthesis.