N-terminal labeling of proteins by the Pictet–Spengler reaction

The Pictet–Spengler reaction was applied to the N-terminal labeling of horse heart myoglobin. This was performed in the following two steps: (1) conversion of the N-terminal glycine residue to an α-keto aldehyde by a transamination reaction and (2) condensation of the resulting activated myoglobin with tryptamine analogues by the Pictet–Spengler reaction. Ultraviolet (UV)/visible (vis) absorption and circular dichroism (CD) spectral data revealed that the tertiary structure of myoglobin was not altered by the Pictet–Spengler reaction.

Graphical abstractThis work describes the methodology for the N-terminal modification of proteins by the Pictet–Spengler reaction.Figure optionsDownload full-size imageDownload as PowerPoint slide