Europhys. Lett.
Volume 70, Number 6, June 2005
Page(s) 850 - 856
Section Interdisciplinary physics and related areas of science and technology
Published online 18 May 2005
Europhys. Lett., 70 (6), pp. 850-856 (2005)
DOI: 10.1209/epl/i2004-10525-6

Stochastic dynamics of magnetosomes in cytoskeleton

V. N. Binhi1 and D. S. Chernavskii2

1  A. M. Prokhorov General Physics Institute RAS - 38 Vavilova St. Moscow 119991, Russian Federation
2  P. N. Lebedev Physics Institute RAS - 53 Leninsky Av. Moscow 119991, Russian Federation

received 28 September 2004; accepted in final form 26 April 2005
published online 18 May 2005

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$\un{rad}$ that facilitates explaining the biological effects of low-frequency weak magnetic fields and geomagnetic fluctuations. Slow magnetic-field variations on the order of 200$\un{nT}$ control the rotations effectively.

87.50.Mn - Effects of radiation and external fields on biomolecules, cells and higher organisms: Magnetic fields.
87.10.+e - Biological and medical physics: General theory and mathematical aspects.
87.16.Ac - Subcellular structure and processes: Theory and modeling; computer simulation.

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