The Interdomain Loop Modulates Conformational Dynamics for the Antibiotic-resistant Activity of TEM-type...

Area of Science:

• Biochemistry
• Molecular Biology
• Microbiology

Background:

• Extended-spectrum β-lactamases (ESBLs) confer resistance to crucial antibiotics.
• TEM-type ESBLs are a significant global health concern due to their prevalence.
• The precise impact of mutations on TEM-type ESBL dynamics and resistance is not fully understood.

Purpose of the Study:

• To investigate how specific mutations (G238S, E104K, M182T) affect the conformational dynamics of TEM-type ESBLs.
• To correlate these dynamic changes with the enzymes' extended-spectrum antibiotic resistance.
• To elucidate the role of the interdomain loop in ESBL function and evolution.

Main Methods:

• Utilized hydrogen/deuterium exchange mass spectrometry (HDX-MS).
• Integrated HDX-MS data with molecular dynamics (MD) simulations.
• Analyzed conformational dynamics of enzyme domains and interdomain loops.

Main Results:

• Individual and combined mutations significantly alter enzyme conformational dynamics across domains and loops.
• The interdomain loop exhibits distinct dynamic responses to different mutations and substrate binding.
• These dynamic changes are linked to the catalytic efficiency and antibiotic resistance.

Conclusions:

• Mutation-driven conformational dynamics are central to TEM-type ESBL antibiotic resistance.
• The interdomain loop plays a critical role in modulating ESBL dynamics and function.
• Findings offer insights for novel inhibitor design and understanding β-lactamase evolution.