Download MendeleyMolecular Mechanism of Antibody-Mediated Activation of Beta-Galactosidase.
Vinothkumar, K.R., Mcmullan, G., Henderson, R.(2014) Structure 22: 621
- PubMed: 24613486
- DOI: https://doi.org/10.1016/j.str.2014.01.011
- Primary Citation of Related Structures:
4CKD - PubMed Abstract:
Binding of a single-chain Fv antibody to Escherichia coli β-galactosidase (β-gal) is known to stabilize the enzyme and activate several inactive point mutants, historically called antibody-mediated enzyme formation mutants. To understand the nature of this activation, we have determined by electron cryo-microscopy the structure of the complex between β-gal and the antibody scFv13R4. Our structure localizes the scFv13R4 binding site to the crevice between domains 1 and 3 in each β-gal subunit. The mutations that scFv13R4 counteracts are located between the antibody binding site and the active site of β-gal, at one end of the TIM-barrel that forms domain 3 where the substrate lactose is hydrolyzed. The mode of binding suggests how scFv stabilizes both the active site of β-gal and the tetrameric state.
Organizational Affiliation:
MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
