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Updated: Mar 21, 2026

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[Magnetic Magnesium Isotope Accelerates ATP Hydrolysis Catalyzed by Myosin]
Biofizika
|May 20, 2016
Summary
Magnetic 25Mg isotopes significantly enhance ATP activity in myosin subfragment-1 by 2.0-2.5 times. This nuclear spin catalysis effect was observed only during enzymatic ATP hydrolysis, not spontaneous reactions.
Area of Science:
- Biochemistry
- Chemical Physics
- Isotope Effects
Context:
- Investigating the role of magnesium isotopes in enzymatic reactions.
- Focusing on the interaction between magnesium and myosin subfragment-1 in ATP hydrolysis.
- Exploring potential nuclear spin effects in biological systems.
Purpose:
- To determine the influence of magnetic (25Mg) versus nonmagnetic (24Mg, 26Mg) magnesium isotopes on ATP activity.
- To elucidate the mechanism behind the observed differences in reaction rates.
- To establish the presence and significance of nuclear spin catalysis in enzymatic ATP hydrolysis.
Summary:
- Experimental studies demonstrated that the magnetic 25Mg isotope increases the ATP activity of isolated myosin subfragment-1 by 2.0-2.5 times compared to nonmagnetic 24Mg and 26Mg isotopes.
- This magnetic isotope effect was exclusively observed during enzymatic ATP hydrolysis, with no effect noted in spontaneous hydrolysis in aqueous solution.
- The findings indicate a significant catalytic role for the magnetic 25Mg isotope, termed nuclear spin catalysis, in the enzymatic breakdown of ATP.
Impact:
- Provides novel insights into isotope effects in enzyme kinetics.
- Suggests a new mechanism (nuclear spin catalysis) influencing biological reaction rates.
- Opens avenues for isotope-based modulation of enzyme activity in biochemical research and potentially therapeutic applications.
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