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Title: QM-cluster model study of CO 2 hydration mechanisms in metal-substituted human carbonic anhydrase II
Abstract Human carbonic anhydrase (CA) metalloenzymes utilize a Zn 2+ -containing active site to catalyze the interconversion of carbon dioxide to bicarbonate. The Zn 2+ ion may be replaced with other divalent transition metals, though the catalytic efficiency of the enzyme will be reduced. In this work, quantum mechanical cluster models of the active site are used to map the reaction profile for the hydration mechanism of carbon dioxide. The Lipscomb proton transfer and Lindskog rotation mechanisms were examined for the native Zn 2+ -enzyme along with variants where the metal was substituted with Cd 2+ , Ni 2+ , Fe 2+ , and Fe 3+ . The findings highlight the impact the metal coordination geometry has on the reaction profile. The results also suggest Fe 2+ , which is the functional metal for a prototypical CA of an anaerobic bacterium, might also be functional for human CA if cultured within an anaerobic environment.  more » « less
Award ID(s):
1846408
NSF-PAR ID:
10431080
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Electronic Structure
Volume:
5
Issue:
1
ISSN:
2516-1075
Page Range / eLocation ID:
014002
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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