Publication Abstract from PubMed
To study the role of hydrogen bonding via interfacial water molecules in protein-protein interactions, we examined the interaction between hen egg white lysozyme (HEL) and its HyHEL-10 variable domain fragment (Fv) antibody. We constructed three antibody mutants (l-Y50F, l-S91A, and l-S93A) and investigated the interactions between the mutant Fvs and HEL. Isothermal titration calorimetry indicated that the mutations significantly decreased the negative enthalpy change (8-25 kJ mol(-1)), despite some offset by a favorable entropy change. X-ray crystallography demonstrated that the complexes had nearly identical structures, including the positions of the interfacial water molecules. Taken together, the isothermal titration calorimetric and x-ray crystallographic results indicate that hydrogen bonding via interfacial water enthalpically contributes to the Fv-HEL interaction despite the partial offset because of entropy loss, suggesting that hydrogen bonding stiffens the antigen-antibody complex.
The role of hydrogen bonding via interfacial water molecules in antigen-antibody complexation. The HyHEL-10-HEL interaction.,Yokota A, Tsumoto K, Shiroishi M, Kondo H, Kumagai I J Biol Chem. 2003 Feb 14;278(7):5410-8. Epub 2002 Nov 19. PMID:12444085[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.