Home | Hydrolases | Amylase | Penicillin Acylase | Pyrophosphatase | Summary and Sources

Summary
By examining not only a specific class of enzymes, but also specific examples of hydrolases, many similarities and differences can be noted. By looking at the hydrolases in general we can see that they all catalyze reactions in which some molecule is broken down into two or more smaller molecules by the addition of water. In the case of amylase, carbohydrates were broken down into monosaccharides. Penicillin acylase breaks down penicillin into its counterparts (though the reaction it catalyses is the reverse in order to produce penicillin). Finally, inorganic pyrophosphatase breaks down polyphosphates and transfers phosphate groups throughout the cell.

Though these may seem similar in a larger sense, they are also very different. They all belong to the same class of enzymes and react similarly as described above, but they also vary in a number of ways. First is the bonds each breaks. The amylase breaks glycosidic bonds, penicillin acylase breaks amide linkages, and pyrophosphatase breaks phosphate bonds. All three of the enzymes also have specific pH conditions that must be met. Each is involved in different cellular processes and are located in different parts of the cell. Besides cellular location, some enzymes such as amylase are only produce by certain organs. All these differences only brush over the vast amounts of subtle yet significant requirements of each enzyme that gives them each specific characteristics. By simply looking at the class of an enzyme, you are only getting a narrow view of the wide possibilities of that enzyme.

Sources
Aghajari, Nushin. Crystal structures of...alpha-amylase...complexed with an inhibitor. Protein Science, vol. 7, pp. 564-572, 1998.

Cooperman, B.S. Toward...description of metal-assisted phosphoryl transfer in pyrophosphatase. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 98 (6): 3121-3126 MAR 13 2001.

Done, Sarah H. Ligand-induced Conformational Change in Penicillin Acylase. Journal of Molecular Biology, iss. 284, pp. 463-475, 1998.

Rydberg, Edwin H. Cloning, mutagenesis, and structural analysis of human pancreatic alpha-amylase expressed in Pichia pastoris. Protein Science, vol. 8, pp. 635-643, 1999.

Stryer, Lubert. Biochemistry [fifth ed.]. W.H. Freeman and Company, New York. 2002.

Websites Used:

http://portal.isiknowledge.com/portal.cgi/wos?Init=Yes&SID=B2aplLHJL4iJbBagjK4

http://pdbbeta.rcsb.org/pdb/Welcome.do