A silent H-bond can be mutationally activated for high-affinity interaction of BMP-2 and activin type IIB receptor.
Weber, D., Kotzsch, A., Nickel, J., Harth, S., Seher, A., Mueller, U., Sebald, W., Mueller, T.D.(2007) BMC Struct Biol 7: 6-6
- PubMed: 17295905 
- DOI: 10.1186/1472-6807-7-6
- Primary Citation of Related Structures:  
2H64, 2H62 - PubMed Abstract: 
Bone morphogenetic proteins (BMPs) are key regulators in the embryonic development and postnatal tissue homeostasis in all animals. Loss of function or dysregulation of BMPs results in severe diseases or even lethality. Like transforming growth factors beta (TGF-betas), activins, growth and differentiation factors (GDFs) and other members of the TGF-beta superfamily, BMPs signal by assembling two types of serine/threonine-kinase receptor chains to form a hetero-oligomeric ligand-receptor complex ...