Structural insights into the interaction of human IgG1 with Fc gamma RI: no direct role of glycans in binding.
Oganesyan, V., Mazor, Y., Yang, C., Cook, K.E., Woods, R.M., Ferguson, A., Bowen, M.A., Martin, T., Zhu, J., Wu, H., Dall'Acqua, W.F.(2015) Acta Crystallogr D Biol Crystallogr 71: 2354-2361
- PubMed: 26527150 
- DOI: https://doi.org/10.1107/S1399004715018015
- Primary Citation of Related Structures:  
4ZNE - PubMed Abstract: 
The three-dimensional structure of a human IgG1 Fc fragment bound to wild-type human Fc¦ÃRI is reported. The structure of the corresponding complex was solved at a resolution of 2.4 ? using molecular replacement; this is the highest resolution achieved for an unmutated Fc¦ÃRI molecule. This study highlights the critical structural and functional role played by the second extracellular subdomain of Fc¦ÃRI. It also explains the long-known major energetic contribution of the Fc `LLGG' motif at positions 234-237, and particularly of Leu235, via a `lock-and-key' mechanism. Finally, a previously held belief is corrected and a differing view is offered on the recently proposed direct role of Fc carbohydrates in the corresponding interaction. Structural evidence is provided that such glycan-related effects are strictly indirect.
Organizational Affiliation: 
Department of Antibody Discovery and Protein Engineering, MedImmune LLC, 1 MedImmune Way, Gaithersburg, MD 20878, USA.