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Molecular Entanglement and Electrospinnability of Biopolymers
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Shear viscosity of two-state enzyme solutions.
Yuto Hosaka1, Shigeyuki Komura1, David Andelman2
1Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo 192-0397, Japan.
Physical Review. E
|February 20, 2020
Summary
This study models enzyme solutions to calculate shear viscosity, finding it depends on substrate concentration and enzyme properties. Results link viscosity to tracer particle diffusion in these solutions.
Area of Science:
- Biophysics
- Chemical Engineering
- Rheology
Background:
- Understanding the rheological properties of enzyme solutions is crucial for biochemical processes.
- Enzymatic conformational changes influence solution viscosity.
Purpose of the Study:
- To determine the shear viscosity of dilute enzyme solutions.
- To investigate the impact of substrate concentration and enzyme properties on viscosity.
Main Methods:
- Modeling enzymes as two-state dimers with elastic springs.
- Utilizing Boltzmann distribution weighted by catalytic cycle waiting times.
- Deriving viscosity expressions based on substrate affinity for fast and slow enzymes.
Main Results:
- Obtained shear viscosity as a function of substrate concentration and physical properties.
- Differentiated viscosity expressions for fast and slow enzymes based on substrate affinity.
- Established a connection between solution viscosity and tracer particle diffusion coefficients.
Conclusions:
- Enzyme-substrate interactions significantly affect solution viscosity.
- The developed model provides insights into the rheology of enzyme solutions.
- Viscosity and diffusion are interrelated in these complex fluid systems.
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