Related Experiment Video
Updated: Jun 20, 2026

The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
Structural and biochemical characterization of the interaction between KPC-2 beta-lactamase and beta-lactamase
Melinda S Hanes1, Kevin M Jude, James M Berger
1Biophysics Graduate Group, University of California, Berkeley, California 94729, USA.
Abstract:
KPC beta-lactamases hydrolyze the "last resort" beta-lactam antibiotics (carbapenems) used to treat multidrug resistant infections and are compromising efforts to combat life-threatening Gram-negative bacterial infections in hospitals worldwide. Consequently, the development of novel inhibitors is essential for restoring the effectiveness of existing antibiotics. The beta-lactamase inhibitor protein (BLIP) is a competitive inhibitor of a number of class A beta-lactamases. In this study, we characterize the previously unreported interaction between KPC-2 beta-lactamase and BLIP. Biochemical results show that BLIP is an extremely potent inhibitor of KPC enzymes, binding KPC-2 and KPC-3 with subnanomolar affinity. To understand the basis of affinity and specificity in the beta-lactamase-BLIP system, the crystallographic structure of the KPC-2-BLIP complex was determined to 1.9 A resolution. Computational alanine scanning was also conducted to identify putative hot spots in the KPC-2-BLIP interface. Interestingly, the two complexes making up the KPC-2-BLIP asymmetric unit are distinct, and in one structure, the BLIP F142 loop is absent, in contrast to homologous structures in which it occupies the active site. This finding and other sources of structural plasticity appear to contribute to BLIP's promiscuity, enabling it to respond to mutations at the beta-lactamase interface. Given the continuing emergence of antibiotic resistance, the high-resolution KPC-2-BLIP structure will facilitate its use as a template for the rational design of new inhibitors of this problematic enzyme.
More Related Videos
Related Concept Videos
Inhibitors of Gram-positive Cell Wall Synthesis
The Equilibrium Binding Constant and Binding Strength
Protein-Drug Binding: Mechanism and Kinetics
Various forces drive these interactions, including hydrogen bonds, hydrophobic interactions, ionic bonds, electrostatic interactions, and van der Waals forces. These bonds enable drugs to bind to specific sites on proteins,...
Protein-protein Interfaces
Enzymes
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme Inhibition

