1. Macronutrients : C,H,N,O,P,S
Nutrition
Macronutrients : C,H,N,O,P,S

2. Carbon Required for the synthesis of all organics Sources
Carbohydrates
Lipids
Proteins
Nucleic acids
 Sources
Organic
Monosaccharides, disaccharides, polysaccharides, proteins, lipids, nucleic acids, phenols, etc.
Inorganic
CO2 and CO

3. Phosphorous Required for the synthesis of: Sources: Nucleic acids
Phospholipids
ATP
Sources:
Organic and inorganic
The inorganic form is the most used

4. Nitrogen Required for the synthesis of: Sources: Amino acids
Nucleic acids
Peptidoglycan
Sources:
Organic: amino acids
Inorganic: NH3, NO3 & N2

5. Sulfur Required for the synthesis of: Sources:
Amino acids (Cysteine/Methionine)
Vitamins (thiamine and biotin)
Sources:
Organic: amino acids
Cysteine and methionine
Inorganic:
S, SO4

6. Hydrogen and Oxygen Required for the synthesis of all organics!
Carbohydrates
Lipids
Proteins
Nucleic acids
Sources:
Organic:
Any organic compound
Inorganic:
H2 (Methanogens only)
H2O (Mainly autotrophs)

7. Nutritional Classification
Carbon source
Heterotrophs :
Preformed organic molecules
Autotrophs:
Inorganic molecules
CO2 and CO

8. Nutritional Classification (cont’d)
Source of energy
Phototrophs:
Light
Chemotrophs:
Oxidation of either organic or inorganic compounds
Source of e-
Organotrophs:
Reduced organic molecules
Lithotrophs:
Reduced inorganic molecules

9. Nutritional Types Nomenclature: Source of Carbon-Energy-Electrons
Ex. Autotroph photolithotroph
Heterotroph photoorganotroph
Autotroph chemolithotroph
Heterotroph chemoorganotroph

10. Producing Energy Oxidative-Respiration Fermentation Aerobic Anaerobic
O2 used as a final e- acceptor
Anaerobic
Inorganic final e- acceptor other than O2 is used
Fermentation
Organic final e- acceptor is used

11. Microbial Energy Metabolism
Glycolytic pathways
Respiration
Fermentation
Chemolithotrophy
Photosynthesis

12. Glycolytic Pathways Glycolysis: Most common glycolytic pathway
Partial oxidation of glucose to pyruvate
Net production of 2 ATP
2 NAD are reduced to NADH
Each of these steps is carried out twice for each glucose molecule

13. Respiration Features Pyruvate is completely oxidized to CO2
NADH is oxidized to NAD
Essential for continued operation of glycolytic pathways
Uses an inorganic electron acceptor
Aerobic respiration: O2 is the final e- acceptor
Anaerobic respiration: An inorganic substance other than O2 is the final e- acceptor
Ex. nitrate, nitrite, sulfate
Additional ATP are made

14. Respiration – Electron Transport Chain
Aerobic respiration :
Final e- acceptor: O2
3 ATP/NADH
2 ATP/FADH
Anaerobic respiration:
Final e- acceptor other than O2:
NO3, NO2, SO4, etc.

15. Fermentation Features Pyruvate is reduced to organic acids or alcohols
Final e- acceptor is organic
NADH is oxidized to NAD:
Essential for continued operation of glycolytic pathways
O2 is not required
No additional ATP made
Gasses (CO2 and/or H2) may be released

16. Culture Media

17. Types of Media Liquid (Broths) Solid media Allows growth in suspension
Uniform distribution of nutrients, environmental parameters and others
Allows growth of large volumes
Solid media
Same as liquid media + solidification agent
Agar: Polysaccharide derived from an algae

18. Growth in Broths Non inoculated clear Turbid + sediment Turbid
Clear + sediment

19. Growth on Agar Growth on solid surface Isolated growth
Allows isolation of single colonies
Allows isolation of pure cultures
Easier for counting colonies and observing morphology of colonies.
Plates are used to:
grow and culture bacteria, fungi, animal tissues, or plant tissues
obtain separated pure cultures of bacteria (plate streaking)
count colonies from serial dilutions
test for growth and reactions on certain materials (such as manitol-salt, or blood agar)
test for bacteria viruses (bacteriophages)
test for resistance to materials (such as antibiotics) or nutritional needs (this is also used to select for bacteria with certain properties or favor the growth of one type/strain over others)
Single colony

20. Solid Media (Cont’d) Slants Stab Growth on surface and in depth
Different availabilities of oxygen
Stab
Semi-solid medium
Long term storage
Low availability of oxygen

21. Nutritional Complexity
Nutritional complexity is a function of the biosynthetic capacity
The greater the biosynthetic capacity, the lower the nutritional requirements

22. Complex Media Composed of rich and complex ingredients
Ex. Soya protein extracts
Milk protein extracts
Blood products
Tomato juice, etc.
Exact chemical composition is unknown
Can be selective and/or differential

23. Defined Media Known chemical composition
Can contain up to 80 different ingredients
Can be very simple
Allows the growth of a restricted number of microorganisms
Composition is highly variable according to the microorganism
Can be selective and/or differential

24. Selective Media
Contain compounds which inhibit or kills the undesired organisms
Ex. Medium containing penicillin only allows the growth of penicillin resistant microorganisms

25. Differential Media Allows to discriminate different species
Often contain pH indicators
Allows to discriminate different metabolisms
Production of alkali changes medium to red
Production of acid changes medium to yellow

26. Environmental Parameters
Oxygen requirements pH
Temperature
Solute concentration/Water availability

27. Oxygen Requirements Aerobic: Microaerophilic:
Absolute requirement of oxygen for survival
Oxygen is used as a final electron acceptor
Oxygen is used by bacteria which have an oxidative metabolism or perform aerobic respiration
Microaerophilic:
Absolute requirement for low oxygen concentrations
High concentrations are deadly

28. Oxygen Requirements (cont’d)
Anaerobic/Aerotolerant:
Oxygen is tolerated but not required
Facultative anaerobes:
Facultative oxygen requirement
Can choose to use oxygen or not
Have an oxygen dependent and an oxygen independent metabolism
Strict or obligate anaerobes:
Oxygen is not used nor tolerated; cannot survive in the presence of oxygen