Head Research Scientist, Department of Kinetics and Catalysis, Institute of Problems of Chemical Physics, Russian Academy of Sciences, Russia
Title: Nuclear spin catalysis in biomolecular nanoreactors: Premises and promises
Vitaly Koltover is Head Researcher at the Department of Kinetics and Catalysis, Institute of Problems of Chemical Physics, the premier organization of Russian Academy of Sciences, Chernogolovka, Moscow Region, Russia. He holds PhD degree in Physics (Candidate of Physical and Mathematical Sciences, Chemical Physics), and SciD degree in Biology (Doctor of Biological Sciences, Biophysics. Published more than 250 papers including books, conference proceedings and papers in the representative journals indexed in Web of Science and Scopus. As invited scientist, he worked in Austria (Vienna), Germany (Rostock, Freiburg), India (Chennai, Mumbai), Israel (Beer Sheva) and USA (National Lawrence Berkeley Laboratory, University of Pennsylvania, Northwestern University). Plenary and oral presentations at the scientific meetings in Russia, Austria, Canada, China, France, Greece, Italy, Israel, Japan, Ukraine and USA. Currently, his main research interests are magnetic isotope effects and nuclear spin catalysis in biology, chemical nano-bionics, reliability (robustness) and aging of biological systems.
Cells are composed from atoms of chemical elements, many of which have magnetic and nonmagnetic stable isotopes. In molecular and chemical physics, magnetic isotope effects (MIEs) have long been known for a number of magnetic isotopes, among them 13C, 17O, 29Si, 33S, 73Ge, and 235U. Not long ago, MIEs were discovered in the experiments with the living cells enriched with the magnetic isotope of magnesium, 25Mg. Moreover, MIEs were revealed in the experiments with one of the most important molecular motors of cell bioenergetics, myosin isolated from smooth muscle. The rate of the enzymatic ATP hydrolysis is 2.0–2.5 times higher with 25Mg than that with the nonmagnetic 24Mg or 26Mg. Besides, MIE was revealed with zinc. While Zn2+ performs the cofactor function less efficiently than Mg2+, it was found that the rate of the ATP hydrolysis driven by myosin is 40-50 percent higher with the magnetic 67Zn as compared to the nonmagnetic 64Zn or 68Zn. Furthermore, the beneficial MIE of 25Mg was discovered in the ATP hydrolysis catalyzed by mitochondrial H+-ATPase isolated from yeast cells and reconstituted into the proteoliposome membrane. On its own, factual evidence of MIE unambiguously indicates that there is a spin-selective rate-limiting step, the “bottle-neck” in the chemo-mechanical cycle of the enzyme that is accelerated by the nuclear spins of 25Mg or 67Zn. Although detailed mechanisms of ability of the biocatalysts to perceive the nuclear magnetism require further investigations, there are the grounds to believe that this new field, nuclear spin catalysis, highlight promising venues for future research in catalysis with possible application of the stable magnetic isotopes in medicine for creating novel anti-stress drugs including the low-toxic anti-radiation protectors. Besides, it opens novel ways for control over efficiency and reliability in optical communications, quantum information processing, computational schemes and the like.