The Fe-CO bond energy in myoglobin: a QM/MM study of the effect of tertiary structure.
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ABSTRACT:
SUBMITTER: Strickland N
PROVIDER: S-EPMC1367296 | biostudies-literature | 2006 Feb
REPOSITORIES: biostudies-literature
Publications
The Fe-CO bond energy in myoglobin: a QM/MM study of the effect of tertiary structure.
Strickland Nikki N Mulholland Adrian J AJ Harvey Jeremy N JN
Biophysical journal 20051230 4
The Fe-CO bond dissociation energy (BDE) in myoglobin (Mb) has been calculated with B3LYP quantum mechanics/molecular mechanics methods for 22 different Mb conformations, generated from molecular dynamics simulations. Our average BDE of 8.1 kcal/mol agrees well with experiment and shows that Mb weakens the Fe-CO bond by 5.8 kcal/mol; the calculations provide detailed atomistic insight into the origin of this effect. BDEs for Mb conformations with the R carbonmonoxy tertiary structure are on aver ...[more]
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