Enzymes in Biology

Enzymes are biological catalysts that speed up chemical reactions in living organisms.
They lower the activation energy required for reactions.

Made of proteins (mostly) or RNA (ribozymes).
Composed of one or more polypeptide chains folded into a specific three-dimensional shape.

Catalyze metabolic reactions, including digestion, energy production, and biosynthesis.
Specificity: Each enzyme acts on a specific substrate due to its unique active site.

Substrate Binding: The substrate binds to the enzyme's active site, forming an enzyme-substrate complex.
Transition State: The enzyme stabilizes the transition state, lowering activation energy.
Product Formation: The substrate is transformed into product(s) and released from the active site.
Enzyme Recovery: The enzyme is free to catalyze another reaction.

Temperature: Each enzyme has an optimal temperature. Excessive heat can denature enzymes.
pH: Enzymes also have an optimal pH. Deviations can reduce activity or denature the enzyme.
Substrate Concentration: Increasing substrate can increase reaction rate until saturation occurs.
Inhibitors: Molecules that decrease enzyme activity. Types include:
- Competitive Inhibitors: Compete with substrates for the active site.
- Non-competitive Inhibitors: Bind to an enzyme at a site other than the active site, altering its function.

Cofactors: Inorganic ions (e.g., Mg²⁺, Zn²⁺) that assist enzyme function.
Coenzymes: Organic molecules (e.g., vitamins) that play a crucial role in enzyme activity.

Essential for metabolic processes and energy production.
Regulation of biochemical pathways.
Involved in DNA replication and repair.
Applications in biotechnology, medicine, and industry (e.g., fermentation, diagnostics).

Study of the rates of enzyme-catalyzed reactions.
Often modeled using the Michaelis-Menten equation, which describes the relationship between substrate concentration and reaction rate.

Allosteric Regulation: Enzymes have allosteric sites where molecules can bind and change enzyme activity.
Feedback Inhibition: End products of a metabolic pathway inhibit an enzyme involved earlier in the pathway to prevent overproduction.

Primarily composed of proteins or RNA (ribozymes).
Consist of one or multiple polypeptide chains folded into a unique three-dimensional structure.

Catalyze vital metabolic reactions, including digestion, energy production, and biosynthesis.
Specificity established through unique active sites tailored to specific substrates.

Substrate Binding: Formation of an enzyme-substrate complex at the active site.
Transition State: Stabilized by the enzyme, which reduces activation energy.
Product Formation: Conversion of substrate into product(s) occurs, followed by their release.
Enzyme Recovery: Makes enzyme available for subsequent reactions.

Temperature: Each enzyme has an optimal temperature; high heat can denature enzymes.
pH: Each enzyme has an optimal pH; changes can inhibit activity or denature the enzyme.
Substrate Concentration: Increased substrate levels can enhance reaction rates until saturation is reached.
Inhibitors: Molecules that reduce enzyme functionality, categorized into:
- Competitive Inhibitors: Compete with substrates for the active site.
- Non-competitive Inhibitors: Bind at different sites, altering enzyme behavior.

Cofactors: Inorganic ions (e.g., Mg²⁺, Zn²⁺) that support enzyme activity.
Coenzymes: Organic compounds (e.g., vitamins) that are essential for enzyme functionality.

Crucial for metabolic processes and energy yield.
Regulate metabolic pathways.
Play roles in DNA replication and repair.
Utilized in biotechnology, medicine, and industrial applications, such as fermentation and diagnostics.

Examines the rates of enzyme-mediated reactions.
Often represented by the Michaelis-Menten equation, illustrating the relationship between substrate concentration and reaction velocity.

Allosteric Regulation: Binding of molecules at allosteric sites alters enzyme activity.
Feedback Inhibition: End products of metabolic pathways inhibit earlier enzymes, preventing overproduction.

Amylase: Enzyme that hydrolyzes starch into sugars.
Protease: Enzyme responsible for breaking down proteins into amino acids.
Lipase: Enzyme that catalyzes the hydrolysis of fats into fatty acids and glycerol.