Allosteric communication in class A β-lactamases occurs via cooperative coupling of loop dynamics
Abstract
Understanding allostery in enzymes and tools to identify it, offer promising alternative strategies to inhibitor development. Through a combination of equilibrium and nonequilibrium molecular dynamics simulations, we identify allosteric effects and communication pathways in two prototypical class A β-lactamases, TEM-1 and KPC-2, which are important determinants of antibiotic resistance. The nonequilibrium simulations reveal pathways of communication operating over distances of 30 Å or more. Propagation of the signal occurs through cooperative coupling of loop dynamics. Notably, 50% or more of clinically relevant amino acid substitutions map onto the identified signal transduction pathways. This suggests that clinically important variation may affect, or be driven by, differences in allosteric behavior, providing a mechanism by which amino acid substitutions may affect the relationship between spectrum of activity, catalytic turnover and potential allosteric behavior in this clinically important enzyme family. Simulations of the type presented here will help in identifying and analyzing such differences.
Data availability
All analysis scripts have been uploaded on figshare with doi 10.6084/m9.figshare.13583384
Article and author information
Author details
Funding
AstraZeneca (Case Studentship)
- Ioannis Galdadas
National Institute of Allergy and Infectious Diseases (R01AI072219)
- Robert A Bonomo
National Institute of General Medical Sciences (GM105978)
- Pratul K Agarwal
National Institutes of Health (RO1AI063517)
- Robert A Bonomo
- Shozeb Haider
Engineering and Physical Sciences Research Council (EP/M022609/1)
- Ana Sofia F Oliveira
- Adrian J Mulholland
Engineering and Physical Sciences Research Council (EP/N024117/1)
- Ana Sofia F Oliveira
- Adrian J Mulholland
Biotechnology and Biological Sciences Research Council (BB/L01386X/1)
- Ana Sofia F Oliveira
- Adrian J Mulholland
Medical Research Council (MR/T016035/1)
- Catherine L Tooke
- James Spencer
- Adrian J Mulholland
National Institute of Allergy and Infectious Diseases (R01AI100560)
- Robert A Bonomo
National Institute of Allergy and Infectious Diseases (R01AI063517)
- Robert A Bonomo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Galdadas et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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