Enzymes

Definition

Enzymes are biological catalysts that speed up chemical reactions in living organisms by lowering the activation energy required for those reactions to occur. They are typically proteins and play essential roles in various biochemical processes, including metabolism and DNA replication. The efficiency of enzymes makes them crucial for maintaining life, and their function can be influenced by factors such as temperature, pH, and substrate concentration.

5 Must Know Facts For Your Next Test

1. Enzymes can be affected by changes in temperature and pH, which can alter their shape and functionality.
2. Many enzymes require cofactors or coenzymes, which are non-protein molecules that assist in enzyme activity.
3. Enzymes exhibit specificity, meaning each enzyme typically catalyzes only one type of reaction or acts on a specific substrate.
4. Immobilizing enzymes can enhance their stability and reusability in various applications, making them valuable in industrial processes.
5. The Michaelis-Menten equation is often used to describe the rate of enzyme-catalyzed reactions, illustrating the relationship between substrate concentration and reaction velocity.

Review Questions

• How do enzymes facilitate biochemical reactions and what factors influence their activity?
  • Enzymes facilitate biochemical reactions by lowering the activation energy required for those reactions to occur, effectively speeding up the process. Their activity can be influenced by several factors including temperature, pH levels, and substrate concentration. For example, each enzyme has an optimal temperature and pH at which it functions best. Deviations from these conditions can lead to decreased activity or denaturation of the enzyme.
• What is the significance of enzyme immobilization in industrial applications?
  • Enzyme immobilization involves attaching enzymes to a solid support or matrix, which allows for their reuse and enhances their stability during chemical processes. This technique is significant in industrial applications because it reduces production costs by allowing enzymes to be recovered and reused multiple times. Additionally, immobilized enzymes can be more resistant to changes in temperature and pH, leading to improved efficiency and consistency in processes like biofuel production or wastewater treatment.
• Evaluate the impact of enzyme specificity on metabolic pathways and overall cellular function.
  • Enzyme specificity plays a crucial role in metabolic pathways by ensuring that each reaction proceeds in a controlled manner, with only the intended substrates being acted upon. This specificity prevents unwanted side reactions that could disrupt cellular function or lead to the accumulation of toxic byproducts. Furthermore, the precise control exerted by enzymes allows cells to efficiently regulate their metabolic activities in response to changing environmental conditions or developmental cues, thus maintaining homeostasis and supporting overall cellular health.

Related terms

Catalysis: The process of increasing the rate of a chemical reaction through the addition of a substance, known as a catalyst, which remains unchanged after the reaction.

Substrate: The specific reactant molecule that an enzyme acts upon during a biochemical reaction, forming an enzyme-substrate complex.

Active Site: The region on an enzyme where the substrate binds and undergoes a chemical reaction, often shaped specifically to fit the substrate.