ISSN:
1432-1327
Keywords:
Key words Heme-based catalysis
;
Axial ligand
;
Molecular orbital calculations
;
Oxygen transfer
;
Peroxidase
;
Cytochrome P450
;
Reaction pathway
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract The present commentary focusses on the role of the axial ligand in peroxidase- and P450-type catalysis. Based on molecular orbital calculations and the experimental evidence available, it is argued that the ligand of a heme-containing enzyme may be a factor in setting the relative chance, although not the intrinsic capability, of the enzyme to catalyse a specific type of heme-based reaction chemistry. The ligand can do so by influencing the electrophilicity, i.e. the redox potential of the high-valency iron-oxo complex, and also by influencing the energy barrier for a reaction pathway through delocalization of valence electrons along the axial ligands, thereby, in the case of a cysteinate but not a histidine axial ligand, stabilizing oxygen transfer pathways.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s007750050068
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