Stochastic dynamics of magnetosomes in cytoskeleton

Considered are the rotations of nanoscopic magnetic particles, magnetosomes, embedded in the cytoskeleton and subjected to the influence of an ac magnetic field and thermal noise. The rotations are studied within a double-well potential formed by mechanical and magnetic forces. It is shown that the motion of the magnetosomes meets the conditions of the so-called "stochastic resonance" under not-too-tight constraints on the elasticity of the cytoskeleton medium. The excursion of regular rotations reaches the value of 2 rad that facilitates explaining the biological effects of low-frequency weak magnetic fields and geomagnetic fluctuations. Slow magnetic-field variations on the order of 200 nT control the rotations effectively.