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Published on: May 4, 2022
On the relationship between efficiency and cooperativity in multi-subunit molecular machines.
Miki Ben-Maimon1, Amnon Horovitz1
1Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Summary
Machine efficiency increases with greater cooperativity between subunits. Optimizing energy differences and binding affinities can further enhance molecular machine performance, guiding design strategies.
Area of Science:
- Biophysics
- Molecular Machines
- Systems Biology
Background:
- Molecular machines exhibit crucial properties like subunit coordination and efficiency.
- Cooperativity among subunits significantly influences the functional output of oligomeric machines.
Purpose of the Study:
- To investigate the relationship between subunit cooperativity and the efficiency of molecular machines.
- To identify key parameters that modulate machine efficiency based on cooperativity.
Main Methods:
- Analysis of theoretical models for oligomeric molecular machines.
- Mathematical modeling to explore the impact of cooperativity and allosteric effects on efficiency.
Main Results:
- Machine efficiency non-linearly increases with rising cooperativity.
- Efficiency is enhanced by increased allosteric constants or higher binding energy in the high-affinity state, but not concurrently.
Conclusions:
- Cooperativity is a critical design principle for enhancing molecular machine efficiency.
- Understanding the interplay between cooperativity, allosteric constants, and binding energies offers pathways for optimizing machine performance.
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