Institute of Problems of Chemical Physics, Russian Academy of Sciences, Russian Federation
pp. 35 - 38
Keywords: magnetic isotopes, nuclear spin, nanoreactors, nanomaterials, reliability, robustness, biosystems
With dimensions of the order of tens angstroms, biomolecular devices are assigned, in modern terminology, to objects of “nanophysics”. At the same time, all of them are composed from chemical elements many of which have magnetic and nonmagnetic stable isotopes, amongst them – carbon, oxygen, silicon, sulphur, calcium, zinc, etc. In chemical physics, the magnetic isotope effects (MIE) have long been known for many magnetic isotopes, from H/D to 235U/238U. Here I present the mini-review of the recent works in which MIE of magnesium have been revealed in living nature. Cations of Mg serve the obligate cofactor functions in cell processes. Meanwhile, Mg has three stable isotopes, 24Mg, 25Mg and 26Mg with natural abundance of approximately 79, 10 and 11 %, from which only 25Mg is magnetic (nuclear spin I = 5/2) whereas 24Mg and 26Mg are nonmagnetic isotopes (nuclear spin I = 0). In experiments with yeast cells, S. cerevisiae, it has been revealed that the enrichment of cells with the magnetic isotope, 25Mg, gives the two-fold increase in the rate constant of post-radiation recovery of the cells when compared to the cells enriched with the nonmagnetic magnesium isotope. In experiments with another commonly accepted cell model, E. coli, it has been revealed that the bacteria essentially faster adapt to the growth media enriched with 25Mg by comparison to the media enriched with 24Mg or 26Mg. Thus, the magnetic isotope of magnesium, by comparison with the non-magnetic ones, essentially accelerates the adaptation of living cells to the stress conditions. Furthermore, effects of different magnesium isotopes on the muscle protein myosin, one of the most important nanoreactors of cell bioenergetics, were investigated. It has been revealed that 25Mg essentially, 2 - 2.5 times by comparison to the spin-less 24Mg or 26Mg, accelerates the reaction of ATP hydrolysis. Thus, we have documented the nuclear spin catalysis in enzymatic hydrolysis of ATP, i.e. – acceleration of mechanochemical cycle of myosin by the nuclear spin of 25Mg. The experimental results of our group provide the grounds of believing that pharmaceutical agents enriched in 25Mg and possibly in the magnetic isotopes of some other elements will find use in nanonuclear biotechnology and medicine for creating novel anti-stress drugs including anti-radiation protectors. Besides, they open novel ways for control over efficiency and reliability of nanoreactors in optical communications, quantum information processing, computational schemes and the like. Koltover, V.K. Stable magnetic isotopes: from spin chemistry to biomedicine. Russian Chem. Bull. (Engl. Translation), 2014, 63, №5, 1029-1035. Koltover, V.K. Nuclear spin effects in physics of living nature. In: Horizons in World Physics. Nova Science Publishing, New York, 2015, pp. 65-78.