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Updated: May 10, 2025
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Selection of Transporter-Targeted Inhibitory Nanobodies by Solid-Supported-Membrane SSM-Based Electrophysiology
Published on: May 3, 2021
2.5K
Energetic and structural control of polyspecificity in a multidrug transporter
Silas T Miller1,2,3, Katherine A Henzler-Wildman3, Srivatsan Raman2,3,4,5
1Cellular and Molecular Biology Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA.
Biorxiv : the Preprint Server for Biology
|April 28, 2025
Summary
Multidrug efflux pumps confer antibiotic resistance. New research reveals how these molecular machines balance energy use and broad substrate recognition, linking efficiency directly to drug transport versatility.
Area of Science:
- Biochemistry
- Molecular Biology
- Microbiology
Background:
- Multidrug efflux pumps are crucial in antibiotic resistance, exporting diverse compounds using ion gradients.
- The molecular mechanisms behind their broad substrate specificity and energy efficiency are not fully understood.
Purpose of the Study:
- To investigate the molecular principles governing multidrug efflux pump substrate recognition and energy coupling.
- To provide a high-resolution view of multidrug transport by deconvoluting key functional contributions.
Main Methods:
- Multiparametric deep mutational scanning across eight substrates and two energy conditions.
- Integration of substrate recognition, energetic coupling, and protein stability data.
- Application of a pH-based selection scheme to assess pH-dependent transport efficiency.
Main Results:
- Substrate specificity is determined by a distributed network of residues, not just the binding site.
- Mutations impact binding, energy coupling, conformational flexibility, and membrane interactions.
- A direct relationship exists: highly efficient pumps show broad substrate profiles, while inefficient ones are narrower.
Conclusions:
- Energy coupling is fundamentally linked to polyspecificity in multidrug efflux pumps.
- This study uncovers the biochemical logic underlying multidrug transport and resistance.
- Findings offer insights into designing novel strategies to combat antibiotic resistance.
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