Biochemistry Playlist: Enzymes Overview

Introduction

• This lecture is part of the biochemistry playlist aimed at preparing for MCAT and related exams.
• Previous topics included amino acids, peptide bonds, protein structures, conjugated proteins, and denaturation.
• Today's focus is on enzymes.

Proteins and Amino Acids

• Proteins: Comprised of polypeptides made from amino acids.
• Types of peptides:
  • Dipeptide
  • Tripeptide
  • Oligopeptide
  • Polypeptide
• Protein structures:
  • Primary: Sequence of amino acids.
  • Secondary: Patterns such as alpha helices and beta-pleated sheets.
  • Tertiary: Three-dimensional structure.
  • Quaternary: Multiple tertiary structures.

Enzymes as Catalysts

• Definition: Enzymes are proteins that act as catalysts, speeding up reactions without being consumed.
• Function:
  • Lower activation energy of reactions.
  • Do not alter the equilibrium or overall energy change (ΔG) of the reaction.
  • Specific for particular reactions or classes of reactions.

Mechanism of Action

• Analogy: Traveling from California to New York
  • Without enzyme: Like traveling in individual cars.
  • With enzyme: Like traveling by airplane (faster and more energy-efficient).
• Enzymes lower the activation energy by providing an easier pathway.
• Changes in pH and temperature can affect enzyme activity.

Enzyme Specificity

• Enzymes are specific to substrates and types of reactions.
• Common types of enzymes discussed:
  • Hydrolases: Break down substances in the presence of water (e.g., trypsin, chymotrypsin).

Graphical Representation

• Activation Energy: The energy required to start a reaction. Visualized as the peak of a graph.
• ΔG (Change in Free Energy): Difference between initial and final states, remains unchanged by enzymes.
• Enzymes lower the activation energy but do not change ΔG.

Conclusion

• Understanding enzymes involves understanding how they lower activation energy and their specificity.
• Next topics will cover enzyme nomenclature and kinetics, including the Michaelis-Menten model.

Additional Resources

• Mention of courses and downloadable materials on medicosisperfectness.com.
• Discount available using promo code "taxidrone".

Study Tips

• Practice drawing graphs and understanding concepts from memory.

End of lecture notes.

Please ensure to review this material for deeper understanding and preparation for upcoming topics in the biochemistry series.