Lecture 01, 2

• What are the energy-rich compounds produced in metabolism?

  ATP and NADH/H+
• How does understanding metabolism aid drug development?

  It helps in designing targeted therapies
• What is the primary role of metabolism?

  Generation of cellular energy
• What is the provision of energy needed for in cells?

  To maintain internal composition
• What are the four purposes of energy in metabolism?

  • Mechanical work (movement)
  • Active transport across membranes
  • Synthesis of molecules
  • Nervous transmission
• What is catabolism?

  Breakdown of complex molecules to simple ones
• What is anabolism?

  Synthesis of complex molecules from simple units
• What is the sum of all chemical reactions in a living organism called?

  Metabolism
• How are metabolic pathways characterised?

  They can be simple, branched, or cyclic

  
• How can changes in one metabolic pathway affect another?

  By altering the availability of substrates
• What does Gibbs free energy (ΔG) measure?

  The maximum energy available for work
• What does a negative ΔG indicate about a reaction?

  It is spontaneous and releases energy
• What is an exergonic reaction?

  A reaction that releases energy
• What is an endergonic reaction?

  A reaction that requires energy input
• What are coupled reactions in metabolism?

  • Reactions where energy from one drives another
  • Essential for efficient energy use in cells
• What is ATP considered in cellular processes?

  The energy currency of the cell
• How is energy released from ATP?

  Through ATP breakdown to ADP and Pi

  
• What is the standard Gibbs energy of hydrolysis of ATP?

  Approximately -30 kJ mol-1

  
• What is substrate phosphorylation?

  Direct ATP production during nutrient breakdown
• What is oxidative phosphorylation?

  Indirect ATP production using electron transport
• What are the two intermediates involved in oxidative phosphorylation?

  NAD+ and FAD

  
• How are NAD+ and FAD reduced during nutrient breakdown?

  By the addition of hydrogen

  
• What happens to reduced NAD+ and FAD in the electron transport chain?

  They are oxidised, passing electrons

  
• What is the final product of oxygen in the electron transport chain?

  Water
• How much ATP is produced from the oxidation of NADH?

  2.5 to 3 ATP
• How much ATP is produced from the oxidation of FADH2?

  1.5 to 2 ATP
• How can metabolic pathways be exploited in drug development?

  • Differences in pathways can target specific enzymes
  • Example: beta-lactams in bacteria
  • Example: ergosterol synthesis in fungi
• What role do enzymes play in metabolic reactions?

  They lower activation energy for reactions
• What are enzymes made from?

  Globular proteins
• Why are cofactors important for enzymes?

  They assist in enzyme function
• What is the summary of metabolism?

  • Sum of all chemical reactions in organisms
  • Involves catabolism and anabolism
  • Coupled reactions for energy efficiency
  • Sources of energy: carbohydrates, fats, proteins
  • ATP as energy currency
  • NAD+ and FAD as important cofactors