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Updated: Jul 5, 2026
08:06
The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
Relationship between chiroptical properties, structural changes and interactions in enzymes: a computational study on
Christo Z Christov1, Tatyana G Karabencheva, Alessio Lodola
1Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, UK. c.christov@sussex.ac.uk
Computational Biology and Chemistry
|April 29, 2008
Summary
Circular dichroism (CD) reveals how chromophore environment affects rotational strengths in beta-lactamase enzymes. This study analyzes these changes to understand enzyme conformational dynamics.
Area of Science:
- Biochemistry and Molecular Biology
- Structural Biology
- Spectroscopy
Background:
- Enzyme functions, including catalysis, binding, and regulation, are intrinsically linked to conformational changes.
- Circular dichroism (CD) spectroscopy is a valuable technique for investigating these dynamic processes.
- Rotational strength (R) is a key characteristic measured in CD spectroscopy, reflecting the chirality of molecular transitions.
Purpose of the Study:
- To investigate the sensitivity of rotational strengths to significant conformational changes in beta-lactamases.
- To determine the influence of the chromophore environment on these rotational strength mechanisms.
- To analyze the impact of local environment (LE) effects on rotational strengths in two class A beta-lactamases.
Main Methods:
- Calculation of rotational strengths using the matrix method, incorporating local environment (LE) effects.
- Utilized X-ray crystallographic structures of enzyme-ligand complexes for the TEM-1 enzyme during its catalytic cycle.
- Employed crystallographic structures of both monomers of the beta-lactamase from B. licheniformis.
Main Results:
- Demonstrated differential sensitivity of rotational strengths to conformational changes based on the chromophore environment in Escherichia coli and B. licheniformis beta-lactamases.
- Quantified the perturbation of rotational strengths due to local interactions within the enzyme structures.
- Provided insights into how local environmental factors modulate the CD spectral characteristics of beta-lactamases.
Conclusions:
- The chromophore environment significantly influences the rotational strength mechanisms in class A beta-lactamases.
- The matrix method, including local environment effects, is effective for analyzing these environmentally dependent spectral changes.
- Understanding these perturbations is crucial for interpreting CD data related to enzyme conformational dynamics and function.
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