Enzymes: Structure and Function
What Are Enzymes?
•Enzymes are biocatalysts.
• increase reaction rates without being used up
• Most enzymes are globular proteins.
• However, some RNA (ribozymes and ribosomal RNA) also catalyze
reactions.
• Enzymes catalytic activity depends on native protein structure. If an
enzyme is denatured catalytic activity is usually lost
How to speed up reactions
Higher temperatures
Stability of macromolecules is limiting
Higher concentration of reactants
Costly as more valuable starting material is needed
Change the reaction by coupling to a fast one
Universally used by living organisms
Lower activation barrier by catalysis
Universally used by living organisms
What Are Enzymes?
•Enzymes are biocatalysts.
• increase reaction rates without being used up
• Most enzymes are globular proteins.
• However, some RNA (ribozymes and ribosomal RNA) also catalyze
reactions.
• Enzymes catalytic activity depends on native protein structure. If an
enzyme is denatured catalytic activity is usually lost
How to speed up reactions
Higher temperatures
Stability of macromolecules is limiting
Higher concentration of reactants
Costly as more valuable starting material is needed
Change the reaction by coupling to a fast one
Universally used by living organisms
Lower activation barrier by catalysis
Universally used by living organisms
