L4-Microbial PART 2 Metabolism Aerobic respiration

• Catabolism


  The process of breaking down organic molecules to release energy
• Chemoorganotrophs


  Organisms that utilize organic carbon molecules for metabolism
• Glycolysis


  1. Breakdown of glucose, producing pyruvate, ATP, and NADH

  2. Occurs in the cytoplasm, is oxygen-independent, and is followed by the Krebs cycle in aerobic conditions or fermentation in anaerobic conditions

  
• Citric Acid Cycle (Krebs Cycle)

  1. Enzyme-catalyzed reactions in the mitochondrial matrix

  2. Key reactions producing ATP, NADH, and FADH2

  3. Roles in the oxidation of organic compounds and biosynthesis of crucial metabolites

  
• Glyoxylate Cycle


  • A modified version of the Citric Acid Cycle that converts acetyl-CoA into succinate for carbohydrate synthesis
  • Two-step bypass involving isocitrate lyase and malate synthase

  
• Fermentation


  1. Anaerobic process releasing energy from glucose

  2. Alcoholic fermentation in yeast produces ethanol and CO2

  3. Lactic acid fermentation in some bacteria and animal cells produces lactic acid

  4. NADH+H+ is the reducing agent, and the energy released is two ATP molecules

  
• Importance of Fermentation


  • Food and Beverage Production
  • Dairy Products
  • Preservation of Food
  • Biotechnology
  • Environmental Applications
  • Health and Medicine
  • Carbon Recycling
  • Flavor Enhancement
• Electron Carriers: NAD & FAD, Cytochromes, Ferredoxin, Quinones
• Electron Transport Chain
• ATP Synthase