TY - JOUR
T1 - Stabilization of the adenosyl radical in coenzyme B12 - A theoretical study
AU - Dölker, Nicole
AU - Maseras, Feliu
AU - Siegbahn, Per E.M.
PY - 2004/3/1
Y1 - 2004/3/1
N2 - Density functional theory B3LYP calculations have been carried out on a large model for coenzyme B12. The dissociation curve for the homolytic cleavage of the Co-C bond has been studied for the free cofactor, in the gas phase and including the effect of a dielectric continuum with a dielectric constant of 4.00, as well as in the presence of some key residues present in methylmalonyl-CoA mutase, an enzyme that depends on coenzyme B 12. We describe a hitherto unknown effect of the cofactor which facilitates the homolysis reaction: electrostatic interactions stabilize the radicals formed in this step. H-bonding to protein residues leads to further stabilization. © 2004 Elsevier B.V. All rights reserved.
AB - Density functional theory B3LYP calculations have been carried out on a large model for coenzyme B12. The dissociation curve for the homolytic cleavage of the Co-C bond has been studied for the free cofactor, in the gas phase and including the effect of a dielectric continuum with a dielectric constant of 4.00, as well as in the presence of some key residues present in methylmalonyl-CoA mutase, an enzyme that depends on coenzyme B 12. We describe a hitherto unknown effect of the cofactor which facilitates the homolysis reaction: electrostatic interactions stabilize the radicals formed in this step. H-bonding to protein residues leads to further stabilization. © 2004 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.cplett.2004.01.048
DO - 10.1016/j.cplett.2004.01.048
M3 - Article
SN - 0009-2614
VL - 386
SP - 174
EP - 178
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 1-3
ER -