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Updated: Apr 17, 2026

Identification of Small Molecule-binding Proteins in a Native Cellular Environment by Live-cell Photoaffinity Labeling
Published on: September 20, 2016
Photo-induced conjugation of tetrazoles to modified and native proteins
Winna Siti1, Amit Kumar Khan, Hans-Peter M de Hoog
1Centre for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Drive 637553, Singapore. MNallani@ntu.edu.sg.
Abstract:
Bio-orthogonal chemistry has been widely used for conjugation of polymer molecules to proteins. Here, we demonstrate the conjugation of polyethylene glycol (PEG) to bovine beta-lactoglobulin (BLG) by photo-induced cyclo-addition of tetrazole-appended PEG and allyl-modified BLG. During the course of the investigation, a significant side-reaction was found to occur for the conjugation of PEG-tetrazole to native BLG. Further exploration of the underlying chemistry reveals that the presence of a tryptophan residue is sufficient for conjugation of tetrazole-modified molecules.

