Magnetic isotope of magnesium accelerates ATP hydrolysis catalyzed by myosin

In this paper, we present the results of experimental studies on the influence of different magnesium isotopes, magnetic ²⁵Mg and nonmagnetic ²⁴Mg or ²⁶Mg, on ATP-hydrolytic activity of the isolated myosin subfragment-1. The reaction rate in the presence of magnetic ²⁵Mg isotope turned out to be 2.0–2.5 times higher than that using non-magnetic ²⁴Mg or ²⁶Mg isotopes. In absence of the enzyme, as at spontaneous ATP hydrolysis in aqueous solution, no magnetic isotope effect was observed. Thus, a significant catalytic effect of the magnetic ²⁵Mg isotope (nuclear spin catalysis) was discovered in the enzymatic hydrolysis of ATP.