Speaker at Catalysis conferences 2021 - Tudor Spataru
Tudor Spataru
Columbia University, USA
Title : The mechanism of the vitamin B12 active forms catalytic processes in human body

Abstract:

For decades Methionine Synthase process has been considered as an energy barrier process by research community. Nevertheless, the in-vivo Methionine Synthase process can, in principle, run unlimited number of its turnovers without side effects and products. This requires two valid conditions for this process: a) the Methionine Synthase process reactions are running without energy barrier; b) the minima of the energy of the Methionine Synthase process reactions correspond to the products formation at each Methionine Synthase process threshold.  CASSF(13,13) approximation has been used for Methionine Synthase process mechanism determination in this research. We have proved that the in-vivo Methionine Synthase process is of full effectiveness, meaning that all reactions are running without energy barrier under influence of the studied process substrate and that the minima of total energy Methionine Synthase reactions correspond to the products formation at each Methionine Synthase process thresholds. This is the first time that this biochemical phenomenon is completely solved.

The Co-C bond cleavage and hydrogen transfer from the substrates to the 5'- deoxy-5’-adenosyl ligand are considered the triggering reactions of adenosylcobalamin cofactor dependent bio-chemical processes by international research community for decades. Moreover, these two reactions have not been distinguished and separate from each other by experimental data up to now.  We have proved that the triggering reaction e. g. the Co-C bond cleavage of the in-vivo  adenosylcobalamin dependent bioprocesses is of full effectiveness, meaning that is running without energy barrier under influence of the studied processes substrates and that the minimum of total energy of Co-C bond cleavage reaction correspond to the full Co-C bond rupture. We also have shown the transfer of the hydrogen from the substrates of the studied bio-processes to 5'- deoxy-5’-adenosyl ligand of the adenosylcobalamin cofactor and the Co-C bond cleavage are closely connected concerted reactions, which cannot be separate from each other and that the hydrogen transfer from substrates of the adenosylcobalamin dependent bioprocesses has a tunneling nature and is energetically convenient. Our data show that, the Co-C bond cleavage is favoring the hydrogen transfer from the substrate to 5’-adenosyl radical, and vice versa.

Audience take-away:

  • The audience will be able to know that the in-vivo Methionine Synthase process is of full effectiveness, meaning that all reactions are running without energy barrier under influence of the studied process substrate and that the minima of total energy Methionine Synthase reactions correspond to the products formation at each Methionine Synthase process thresholds. This is the first time that this biochemical phenomenon is completely solved.
  • This research that other faculty could use to expand their research or teaching the Co-C bond cleavage and hydrogen transfer from the substrates to the 5'- deoxy-5’-adenosyl ligand are considered the triggering reactions of adenosylcobalamin cofactor dependent bio-chemical processes by international research community for decades. Moreover, these two reactions have not been distinguished and separate from each other by experimental data up to now.  And the triggering reaction e. g. the Co-C bond cleavage of the in-vivo  adenosylcobalamin dependent bioprocesses is of full effectiveness, meaning that is running without energy barrier under influence of the studied processes substrates and that the minimum of total energy of Co-C bond cleavage reaction correspond to the full Co-C bond rupture. 

Biography:

Profesor Tudor Spataru studied Chemistry at the Cishinau State University, Republic of Moldova and graduated Thesis  in 1972. He then joined the research group of Prof. Bersucher at the Institute of  Chemistry, Moldovien Academy of Sciences . She received her PhD degree in 1985 at the same institution. A long time is an Associate Professor at the Department of Chemistry, Columbia University and Profesor at Natural Sciences Department, Hostos Community College. Published more than 100 research articles in SCI(E) journals.

Watsapp