|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.50A [2011] >
IJC-A Vol.50A(03-04) [March-April 2011] >
| Title: | Density functional theory investigations of the catalytic mechanism of  -carbonic anhydrase |
| Authors: | Hakkim, V
Rajapandian, V
Subramanian, V |
| Keywords: | Bioinorganic chemistry
Theoretical chemistry
Catalysis
Reaction mechanisms
Metalloenzymes
Carbonic anhydrase |
| Issue Date: | Mar-2011 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | Carbonic anhydrase (CA) is an enzyme that
catalyses the reversible hydration of carbon dioxide. There are three broad
classes  , , and  , of CA, divided into three genetically unrelated families,
namely, animal, plant, and bacterial CAs, respectively. The active site of this
enzyme contains a zinc atom which is necessary for catalysis. In this study,
the catalytic mechanism of -CA has been investigated using its active site
model employing DFT based Becke’s three parameter exchange and B3LYP method. It
is evident from the results that the activation barrier for the nucleophilic
attack is negligible, which is similar to that of -CA. Furthermore, results
show that Asp162-Arg164 dyad and Glu151 residues play a decisive role in the
catalysis. Primarily, the catalytic dyad orients the hydroxyl group
appropriately to enable nucleophilic attack and stabilizes the negative charge
on the bicarbonate. |
| Page(s): | 503-510 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-0975(Online); 0376-4710(Print) |
| Source: | IJC-A Vol.50A(03-04) [March-April 2011]
|
|
