Corrin ring-induced redox tuning

Abstract

The density functional calculations suggest that the expansion of the corrin macrocycle's N₄ core by 0.06–0.10 Å leads to an appreciable lowering of 100–150 mV vs. saturated calomel electrode in the reduction potentials of two biologically important B₁₂ cofactors namely methylcobalamin and adenosylcobalamin respectively. This redox tuning of B₁₂ cofactors may encourage the electron transfer-based activation mechanism for B₁₂-dependent enzymes.