1. Microbial Metabolism

2. A. Basic Concepts Definitions
Metabolism: The processes of catabolism and anabolism
Catabolism: The processes by which a living organism obtains its energy and raw materials from nutrients
Anabolism: The processes by which energy and raw materials are used to build macromolecules and cellular structures (biosynthesis)

4. Overview of cell metabolism

5. What are nutrients that bacteria want?
C Sugar, Lipid Energy, Biosynthesis
N Protein Biosynthesis
O Air Energy

6. Breakdown Synthesis Proteins to Amino Acids, Starch to Glucose
Amino Acids to Proteins, Glucose to Starch

7. Bacterial Metabolism ☺
  Exoenzymes: Bacteria cannot transport large polymers into the cell. They must break them down into basic subunits for transport into the cell. Bacteria therefore elaborate extracellular enzymes for the degradation of carbohydrates to sugars (carbohydrases), proteins to amino acids (proteases), and lipids to fatty acids (Lipases).

8. Energy Generating Patterns
After Sugars are made or obtained, they are the energy source of life.
Breakdown of sugar(catabolism) different ways:
Aerobic respiration
Anaerobic respiration
Fermentation

9. Aerobic respiration Most efficient way to extract energy from glucose.
Process: Glycolysis
Kreb Cycle
Electron transport chain
Glycolysis: Several glycolytic pathways
The most common one:
glucose-----> pyruvic acid + 2 NADH + 2ATP

10. B. Glycolytic Pathways
4 major glycolytic pathways found in different bacteria:
Embden-Meyerhoff-Parnas pathway
“Classic” glycolysis
Found in almost all organisms
Hexose monophosphate pathway
Also found in most organisms
Responsible for synthesis of pentose sugars used in nucleotide synthesis
Entner-Doudoroff pathway
Found in Pseudomonas and related genera
Phosphoketolase pathway
Found in Bifidobacterium and Leuconostoc

15. Formation of intermediates of the Embden– Meyerhof–Parnas (EMP) and Entner–Doudoroff (ED) pathway from carbohydrates other than glucose

17. BIOCHEMICAL REACTIONS OF RESPIRATION

18. Carbohydrate Metabolism
4. TCA cycle

20. Anaerobic respiration
Final electron acceptor : never be O2
Sulfate reducer: final electron acceptor is sodium sulfate (Na2 SO4)
Methane reducer: final electron acceptor is CO2
Nitrate reducer : final electroon acceptor is sodium nitrate (NaNO3)
O2/H2O coupling is the most oxidizing, more energy in aerobic respiration.
Therefore, anaerobic is less energy efficient.

21. C. Fermentation Features of fermentation pathways
Pyruvic acid is reduced to form reduced organic acids or alcohols.
The final electron acceptor is a reduced derivative of pyruvic acid
NADH is oxidized to form NAD: Essential for continued operation of the glycolytic pathways.
O2 is not required.
No additional ATP are made.
Gasses (CO2 and/or H2) may be released

24. Fermentation Glycosis: Glucose ----->2 Pyruvate + 2ATP + 2NADH
Fermentation pathways
a. Homolactic acid F.
P.A -----> Lactic Acid
eg. Streptococci, Lactobacilli
b.Alcoholic F.
P.A -----> Ethyl alcohol
eg. yeast

33. Nutrition
Table 27.1

34. Alternative energy generating patterns(3)

35. Alternative energy generating patterns(4)

36. Energy/carbon classes of organisms

38. Fig. 5-12

39. Overview of Metabolism