Magnetosensitivity of bacteria E. coli: Magnetic isotope and magnetic field effects.

The biological effects of a 25 Mg nuclear spin and weak magnetic fields have been found and studied by using bacterial cells of Escherichia coli (E. coli) grown on standard M9 nutrient media with different isotopes of magnesium: 24 Mg, 25 Mg, 26 Mg, and a natural mixture of Mg isotopes. Among these isotopes only 25 Mg has a nuclear spin I = 5/2 and nuclear magnetic moment which have been known to affect enzymatic processes in vitro due to hyperfine interactions with uncoupled electrons of substrates. Other non-magnetic magnesium isotopes, 24 Mg and 26 Mg, have neither a nuclear spin (I = 0) nor a nuclear magnetic moment. Bacterial cells grown on 25 Mg-media and enriched with this isotope manifest a higher growth rate and colony-forming units (CFU) compared with cells grown on media containing nonmagnetic 24 Mg and 26 Mg isotopes. Magnetic field dependencies of CFU cells enriched with different magnesium isotopes have been obtained. The observed isotope-dependent differences are explained by intracellular enzymatic ion-radical reactions which are magnetic field and nuclear spin sensitive. Enzymatic synthesis of ATP is considered as the most probable magnetosensitive biochemical process in vivo as far as effectiveness of ATP production is concerned; it determines the viability of cells and was shown in vitro as a nuclear spin-dependent reaction. Bioelectromagnetics. 38:581-591, 2017. © 2017 Wiley Periodicals, Inc.