On-site reaction for PPAR gamma modification using a specific bifunctional ligand
Kojima, H., Itoh, T., Yamamoto, K.(2017) Bioorg Med Chem 25: 6492-6500
- PubMed: 29097031 
- DOI: https://doi.org/10.1016/j.bmc.2017.10.024
- Primary Citation of Related Structures:  
5WQX, 5WR0, 5WR1 - PubMed Abstract: 
Site-specific labeling is an important methodology to elucidate the biological function of a target protein. Here, we report a strategy for site-specific chemical labeling, termed the "on-site reaction". We designed and readily synthesized a bifunctional ligand possessing two reaction sites, an enone and an azide moiety. This strategy involves an on-site conjugate addition reaction with protein followed by a Hüisgen cycloaddition reaction. We demonstrate this strategy by using fluorescein as a probe and peroxisome proliferator activated receptor γ (PPARγ) as a target protein. The reactions were evaluated by ESI-mass analysis and the binding site and modes of binding were revealed by X-ray crystallization analysis. The proposed methodology can easily convert a covalent ligand into chemical tool for protein functional analysis and the identification of drug targets.
Organizational Affiliation: 
Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan.