title: Site-Specific Protein Bioconjugation via a Pyridoxal 5'-Phosphate-Mediated N-Terminal Transamination Reaction.
abstract: The covalent attachment of chemical groups to proteins is a critically important tool for the study of protein function and the creation of protein-based materials. Methods of site-specific protein modification are necessary for the generation of well defined bioconjugates possessing a new functional group in a single position in the amino acid sequence. This article describes a pyridoxal 5'-phosphate (PLP)-mediated transamination reaction that is specific for the N-terminus of a protein. The reaction oxidizes the N-terminal amine to a ketone or an aldehyde, which can form a stable oxime linkage with an alkoxyamine reagent of choice. Screening studies have identified the most reactive N-terminal residues, facilitating the use of site-directed mutagenesis to achieve high levels of conversion. Additionally, this reaction has been shown to be effective for a number of targets that are not easily accessed through heterologous expression, such as monoclonal antibodies. Curr. Protoc. Chem. Biol. 2:125-134 © 2010 by John Wiley & Sons, Inc.
authors.affiliation: University of California, Berkeley, Department of Chemistry, Berkeley, California.
authors.forename: Leah S
authors.initials: LS
authors.lastname: Witus
authors.forename: Matthew
authors.initials: M
authors.lastname: Francis
keywords: N‐terminus; PLP; bioconjugation; oximation; pyridoxal phosphate