18 by: Megan Martin
Student – Megan Martin
Name of Enzyme & E.C. number – carbonic anhydrase; 4.2.1.1
Where is enzyme found? The focus was specifically on carbonic anhydrase II, as there is 15 different carbonic anhydrases found in the human body. Carbonic anhydrase II can be found in both the kidney and the brain respectively
What does the enzyme do? Carbonic anhydrase is an enzyme that is classified as a metalloenzyme, which refers to an enzyme that uses a metal cation as a cofactor in the enzyme’s active site. The purpose of carbonic anhydrase is to preform the reversible reaction of converting carbon dioxide and water into bicarbonate and protons. It is known that an increase in carbon dioxide will directly influence the pH of blood. In such, increased levels of carbon dioxide will lower this pH, which subsequently lowers oxygen-hemoglobin binding. The stability of these essential processes can be attributed to carbonic anhydrase as it reduces the amount of carbon dioxide found in blood.
Interesting facts about carbonic anhydrase:
Carbonic anhydrase has both a hydrophilic and a hydrophobic pocket.
The zinc core of the enzyme is fixed into a tetrahedral coordination.
Although this enzyme is considered a metal-ion catalyst due to the zinc core, the enzyme also performs acid-base catalyst.
Carbonic anhydrase can bind to multiple different substrates, and its efficiency is only restricted by that diffusion rate
Carbonic anhydrase is one of the faster enzymes
Carbonic anhydrase inhibitors fall into a class of medicine that helps treat the conditions of glaucoma
References
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