Question

The following reaction is catalyzed by the enzyme urease. To what class of enzymes does urease belong?

Short answer

Urease belongs to the hydrolase class of enzymes.

Step-by-step solution

Understand the Role of Urease

Urease is an enzyme that catalyzes the hydrolysis of urea, converting it into ammonia and carbon dioxide. This means that urease facilitates the breakdown of urea by adding a water molecule to it, a process crucial in nitrogen metabolism.

Identify Enzyme Classes

There are six major classes of enzymes: oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases. Each class is defined by the type of reaction they catalyze.

Match Reaction Type to Enzyme Class

Hydrolases are the class of enzymes that catalyze the cleavage of bonds via the addition of water, a process known as hydrolysis. Since urease catalyzes the hydrolysis of urea, it falls under this class.

Confirm with Urease Reaction

The specific reaction catalyzed by urease is: \[\text{urea} + \text{H}_2\text{O} \rightarrow \text{ammonia} + \text{carbon dioxide}\]This clearly demonstrates a hydrolysis reaction, confirming that urease is a hydrolase.

Key concepts

Understanding Urease

Urease is a fascinating enzyme that plays a significant role in breaking down urea through a process known as hydrolysis. Urea is a compound that contains nitrogen, and when urease acts upon it, the molecule is split into ammonia and carbon dioxide. This enzymatic action involves the addition of a water molecule, which helps in breaking the chemical bonds in urea. By doing so, urease aids in nitrogen metabolism. This is essential for many organisms as it helps convert nitrogen from a less usable form in urea to more readily usable forms, such as ammonia, which can be further processed by biological systems.

Role of Hydrolase Enzymes

Enzymes are categorized into several classes based on the type of reaction they facilitate. Hydrolases are one such class. These enzymes are responsible for catalyzing reactions that involve breaking chemical bonds through the addition of water. This is called hydrolysis.

• Hydrolases participate in a wide range of biological processes.
• They not only help in breaking down large molecules but also assist in the metabolism of various compounds.

Urease is a specific example of a hydrolase enzyme because it helps in the hydrolysis of urea. By facilitating the breakdown of this nitrogen-containing compound, urease proves critical in many biological pathways involving nitrogen.

Nitrogen Metabolism Significance

The process of nitrogen metabolism involves the transformation of nitrogenous compounds into forms that can be utilized by living organisms. Urease, as a hydrolase enzyme, is an integral part of this process as it converts urea, a waste product with excess nitrogen, into ammonia.

• Ammonia can then be assimilated into amino acids or other nitrogenous compounds necessary for life.
• This process is crucial for maintaining the nitrogen balance within organisms, especially in plants and certain bacteria.

Without enzymes like urease, the nitrogen cycle would be inefficient, limiting the availability of nitrogen in a practical form for biological use.

Basics of Enzyme Catalysis

Enzyme catalysis refers to the acceleration of chemical reactions by enzymes. Enzymes, including urease, act as catalysts to increase the reaction rate without being consumed in the process. They are incredibly specific in their action.

• Each enzyme only catalyzes one kind of reaction or acts on a particular substrate.
• They lower the activation energy required for a reaction, which means the reaction takes place more easily and quickly.

For instance, urease specifically catalyzes the hydrolysis of urea, effectively speeding up the conversion of urea into ammonia and carbon dioxide. Enzymes like urease are indispensable in supporting life due to their role in facilitating necessary biochemical reactions efficiently.