Magnetic-isotope effect of magnesium in the living cell

Abstract

12 1 There is a great variety of chemical elements which have both kinds of stable isotopes, nonmagnetic and magnetic ones. For example, among three stable iso topes of magnesium, 24 Mg, 25 Mg, and 26 Mg with natu ral abundance of approximately 78.99, 10.00, and 11.01%, 25 Mg is magnetic isotope (it has nuclear spin I = 5/2) while 24 Mg and 26 Mg are nonmagnetic iso topes (nuclear spin I = 0) [1]. In this work we studied the influence of different isotopes of magnesium on cells of Escherichia coli and found that the cells which were grown on magnetic isotope, 25 Mg, essentially faster adapt to the new media by comparison with the cells which were grown on the nonmagnetic isotopes. Thus, we have experimentally revealed, for the first time, the magnetic isotope effect in vivo.The solutions of the magnesium sulphate were pre pared from the relevant oxides, 24 MgO, 25 MgO, and 26 MgO, with the isotope enrichment, correspondingly, 99.8, 98.8, and 97.7 atomic percent (Federal State Unitary Enterprise "Integrated Plant Electrohimpri bor," RosAtom). Experiments were performed with bacteria E. coli, "museum" strain K12TG1, which were cultivated on the solid lactose BCP agar (Bio Merieux, France) in accordance with the standard design [2, 3]. The bacterial inoculates have been pre viously incubated for 24 h in the artificial liquid nutri ent medium M9, that was composed from 8 g of glu cose, 2 g of NH 4 Cl, 12 g of Na 2 HPO 4 , 6 g of K 2 HPO 4 , 1 g of NaCl in 1 liter of distilled water, pH 7.0, without magnesium. Thereafter, the equal aliquots of the cells (400 µL) were suspended in 50 mL of the same medium but supplemented with 24 Mg, 25 Mg, or 26 Mg 1 The article was translated by the authors. as 2.2 mM of 24 MgSO 4 , 25 MgSO 4 , or 26 MgSO 4 , and were then cultivated under the conditions of continu ous aeration with shaking at 37°C. The experiments with different isotopes were performed simulta neously, three bacteria samples with each kind of the isotope, a total of 9 samples under the same conditions in parallel. According to the data of high resolution mass spectrometry (spectrometer ICP-MS "Ele ment-2," USA), the element compositions of the media were the same for all samples with amounts of contaminants no more than 10 -6 M, no matter which kind of magnesium isotope was used. Kinetics of the cell growth was hourly monitored by optical density measurements at 620 nm (OD 620 ) using multi channel immunoenzyme analyzer "Uniplan" (Picon, Russia). The colony forming ability of bacteria was tested by the routine technique of seeding the cells, which entered the stationary phase of growth, on the solid nutrient media (BCP-agar) accompanied by count ing the colonies after incubation for 16 h at 37°C [2, 3]. The experimental sessions were replicated twice with different microbial inoculates.The kinetic curves of growth of the cell cultures in our experiments were of the standard form: the phase of relatively slow adaptation to the new growth media ("lag-phase") followed by the rapid phase of expo nential growth ("log-ph...

Enzymatic mechanisms of biological magnetic sensitivity

“…Moreover, it has been proven experimentally for both chemical [Salikhov et al, 1984;Steiner and Ulrich, 1989] and enzymatic reactions [Banerjee, 2003;Fontecave et al, 2003;Toraya, 2003]. Spin dependencies of some enzymatic reactions have been demonstrated in vitro using isolated phosphorylating enzymes [Buchachenko et al, 2005a;Buchachenko, 2009], mitochondria [Buchachenko et al, 2005b], and in vivo in experiments with Escherichia coli (E. coli) bacteria [Koltover et al, 2012;Shevchenko et al, 2012]. However, to explain the peculiarities of these experiments and to predict results of future experiments, a coherent theory of magnetosensitive enzymatic reactions is necessary.…”

Stable Magnetic Isotopes as a New Trend in Biomedicine

“…However, for the exponential phase of the cell growth, we have not found any significant differences in the rates of cell growth between magnetic 25 Mg and nonmagnetic 24 Mg and 26 Mg. The time of doubling of the cell mass was approximately the same, regardless of the type of magnesium isotopes (Koltover et al, 2012). This obviously suggests a different "bottle-neck" of metabolism in the exponential phase of growth with other, than ATP, limiting substrate and another limiting reaction independent upon the nuclear spin of magnesium.…”

“…Vitaly K. Koltover (2012). Stable Magnetic Isotopes as a New Trend in Biomedicine, Biomedicine, Dr. Chao Lin (Ed.…”

“…Inasmuch as the total SOD activity is normally adjusted to the intracellular level of О 2 •─ , the reduced level of SOD in the cells can be considered as evidence for lower production of О 2 •─ as the failure by-product of cell respiration. Thereafter, these experiments have been replicated in cooperation with the microbiologists of Orenburg State University using another strain of E. coli, K12TG1 (Koltover et al, 2012). After cultivation for 24 h in the artificial liquid minimal M9-medium without magnesium (and without tap water), the cells were suspended in the fresh M9-medium supplemented with different isotopes of magnesium as 0.…”

Stable magnetic isotopes: from spin chemistry to biomedicine

“…2, b). 23 In all of our experiments, the elemental composition (from lithium to uranium) of all samples was analyzed by atomic emission spectroscopy and high resolution mass spectrometry at the Institute of Microelectronics Tech nology and High Purity Materials, Russian Academy of Sciences (the Analytical Center headed by V. K. Karan dashev). According to the results of analysis, the detected differences could not be attributed to any impurity ele ments.…”