Enzymes as Biological Catalyst Research Assignment Paper

Enzymes Student’s Name
Institutional Affiliation
Enzymes
Enzymes as Biological Catalyst
Enzymes refers to the protein chemical that acts as a catalyst to speed up chemical reactions by lowering the activation energy required. In other words, It catalyses nearly all the chemical reactions that occurs in the body cells (Hanninen & Atalay, 2009).
Enzymes have an adapted special three- dimensional shape that gives it a large surface area to fit into the shapes of the reactants. Reactants are also known as substrates.
An enzyme has a section known as the active site, which is very essential (Hanninen & Atalay, 2009). The active site has a unique shape and chemical surroundings that makes the chemical reactions easy and faster. In other words, the active part of an enzyme is a part inside the enzyme that fits into the shape of a substrate molecules (DeChancie, 2008).
The amino acid align in series of chains to cover the substrate through salt-bridges, H-bonding, as well as hydrophobic interactions. When the reactions is fully complete, products are released, as they no longer fit the active sites after the reactions. Sometimes additional non-protein molecules are required to aid reaction for some enzymes (DeChancie, 2008).
Tightly bounded cofactors are referred as prosthetic groups. Cofactors that are bound and released easily are called coenzymes. Many vitamins acts as coenzymes (DeChancie, 2008).
Naming Enzymes
Enzymes names usually ends –ase to identify the reacting substance. For instance, enzyme sucrace catalyses the hydrolysis of sucrose. Also, the naming is framed to describe the specific function of the enzyme (DeChancie, 2008). For example, enzyme oxidase is named according to its oxidation reaction functions. Sometimes, enzyme are named randomly, especially the digestion enzymes such as Pepsin and Trypsin (DeChancie, 2008).
Classification of Enzymes
Enzymes are classified according to the type of reactions they catalyse.
Class

Reactions Catalysed

Oxidoreductases

Oxidation

Transferases

Transfer groups of atoms

Hydrolases

Hydrolysis

Lyases

Add atoms, remove atoms

Isomeris

Rearrange atoms

Ligases

Use ATP to combine molecules

Enzymes Specificity
Enzymes have to prove to possess varying degrees of specificity for substrates. In addition, enzymes are likely to identify and catalyse either a single substrate, a group of similar substrates or a specific type bond (DeChancie, 2008).
Types of Enzyme Specificity

Types

Reaction Type

Example

Absolute

Catalyse a single type of reaction for single substitute

Urease catalyses only the hydrolysis of urea

Group

Catalyse one type of reaction for similar substrates

Hexokinase adds a phosphate group of hexoses

Linkage

Catalyse one type of reactions for a specific type of bond

Chymotrypsin catalyses the hydrolysis of peptide bonds.

Lock-and-Key Model
The lock-and-key model explains the enzyme actions...