Water-Restructuring Mutations Can Reverse the Thermodynamic Signature of Ligand Binding to Human Carbonic Anhydrase.Fox, J.M., Kang, K., Sastry, M., Sherman, W., Sankaran, B., Zwart, P.H., Whitesides, G.M.
(2017) Angew. Chem. Int. Ed. Engl. 56: 3833-3837
- PubMed: 28252841
- DOI: 10.1002/anie.201609409
- Primary Citation of Related Structures:
- PubMed Abstract:
This study uses mutants of human carbonic anhydrase (HCAII) to examine how changes in the organization of water within a binding pocket can alter the thermodynamics of protein-ligand association. Results from calorimetric, crystallographic, and theor ...
This study uses mutants of human carbonic anhydrase (HCAII) to examine how changes in the organization of water within a binding pocket can alter the thermodynamics of protein-ligand association. Results from calorimetric, crystallographic, and theoretical analyses suggest that most mutations strengthen networks of water-mediated hydrogen bonds and reduce binding affinity by increasing the enthalpic cost and, to a lesser extent, the entropic benefit of rearranging those networks during binding. The organization of water within a binding pocket can thus determine whether the hydrophobic interactions in which it engages are enthalpy-driven or entropy-driven. Our findings highlight a possible asymmetry in protein-ligand association by suggesting that, within the confines of the binding pocket of HCAII, binding events associated with enthalpically favorable rearrangements of water are stronger than those associated with entropically favorable ones.
Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA.,Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.,Schrödinger, Inc., 120 West 45thStreet, New York, NY, 10036, USA.,Schrödinger, Sanali Infopark, 8-2-120/113 Banjara Hills, Hyderabad, 11937, Andhra Pradesh, India.