Structural evidence for substrate strain in antibody catalysisYin, J., Andryski, S.E., Beuscher IV, A.E., Stevens, R.C., Schultz, P.G.
(2003) Proc Natl Acad Sci U S A 100: 856-861
- PubMed: 12552112
- DOI: https://doi.org/10.1073/pnas.0235873100
- Primary Citation of Related Structures:
1N7M, 1NGW, 1NGX, 1NGY, 1NGZ
- PubMed Abstract:
The crystal structure of the Michaelis complex between the Fab fragment of ferrochelatase antibody 7G12 and its substrate mesoporphyrin has been solved to 2.6-A resolution. The antibody-bound mesoporphyrin clearly adopts a nonplanar conformation and reveals that the antibody catalyzes the porphyrin metallation reaction by straining/distorting the bound substrate toward the transition-state configuration. The crystal structures of the Fab fragment of the germ-line precursor antibody to 7G12 and its complex with the hapten N-methylmesoporphyrin have also been solved. A comparison of these structures with the corresponding structures of the affinity-matured antibody 7G12 reveals the molecular mechanism by which the immune system evolves binding energy to catalyze this reaction.
Department of Chemistry, University of California, Berkeley, CA 94720, USA.