1. Bacterial Metabolism
Metabolism
Sum up all the chemical processes that occur within a cell
1. Anabolism: Synthesis of more complex compounds and use of energy
2. Catabolism: Break down a substrate and capture energy

2. Overview of cell metabolism

3. Bacterial Metabolism Autotroph: Photosynthetic bacterial
Chemoautotrophic bacteria
Heterotroph:
Parasite
Saprophyte

4. 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

5. Photosynthesis (1) Higher plants Light reaction:
Photolysis of H2O produce ATP and NADPH
Two photosystem (I & II)
Dark fixation: use the production from light reaction (ATP and NADPH) to fix CO2
Reaction:
6CO2 + 6H2O > C6H12O6 +6O2
(Light and chloroplast)

8. Bacteria Photosynthesis
i. Only one photosystem can not do photolysis of H2O
ii. H2O not the source of electron donor
iii. O2 never formed as a product
iv. Bacterial chlorophyll absorb light at longer
W.L.
v. Similar CO2 fixation
vi. Only has cyclic photophosphorylation

9. How the Bacteria synthesize NADPH
Grow in the presence of the H2 gas
H2 + NADP  NADPH2
hydrogenase
Reverse the electron flow in the e- transport chain
H2S S
S + NADP  SO4-2 + NADPH2
Succinate Fumarate
Simple non-cyclic photosynthetic e- flow

10. Chlorophyll a and bacteriochlophyll a(1)

11. Chlorophyll a and bacteriochlophyll a(2)

12. Anoxygenic photosynthesis

13. Anoxygenic versus oxygenic phototrophs(2)

14. Anoxygenic versus oxygenic phototrophs(1)

15. Photosynthetic bacteria
(1) Chlorobium-green sulfur bacteria
Use green pigment chlorophyll
Use H2S (hydrogen sulfide), S (sulfur), Na2S2O3 (sodium thiosulfate) and H2 as e- donors.
(2) Chromatium-purple sulfur bacteria
Use purple carotenoid pigment, same e-donors
(3) Rhodospirillum-non sulfur purple bacteria
Use H2 and other organic compounds such as isopropanol etc, as e-donors.
Reaction: CO2 + 2H2A -----> CH20 + H20 +2A
A is not O

16. Chemautotroph
Some bacteria use O2 in the air to oxidize inorganic compounds and produce ATP (energy). The energy is enough to convert CO2 into organic material needed for cell growth.
Examples:
Thiobacillus (sulfur S)
Nitorsomonas (ammonia)
Nitrobacter (nitrite)
Various genera (hydrogen etc.)

17. 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

18. Aerobic respiration Euk.
glucose -----> G-6-P----->F-6-P----->
…... 2 pyruvate +2ATP + 2NADH
Prok.
glucose-----> G-6-P------>F-6-P
Process take places during transport of the substrate. Phosphate is from phosphoenolpyruvate (PEP)
> 2 pyruvate +2ATP + 2NADH

19. Pyruvate + 4NAD + FAD ----->
Kreb cycle:
Pyruvate + 4NAD + FAD ----->
3CO2 +4NADH + FADH
GDP + Pi -----> GTP
GTP + ADP -----> ATP + GDP
Electron trasnport Chain
4HADH > 12 ATP
FADH > 2 ATP Total 15 ATP
Glycolysis > 8 ATP
Total equation:
C6H12O6 + 6O > 6CO2 + 6H2O + 38 ATP

25. Generation of a proton-motive force(1)

26. Generation of a proton-motive force(2)

27. Mechanism of ATPase

28. 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.

32. 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

35. c. Mixed acid fermentation
P.A -----> lactic acid
acetic acid
H2 + CO2
succinic acid
ethyl alcohol
eg. E.coli and some enterbacter
d. Butylene-glycol F.
P.A -----> 2,3, butylene glycol
eg. Pseudomonas
e. Propionic acid F.
P.A -----> 2 propionic acid
eg. Propionibacterium

36. Alternative energy generating patterns(1)

37. Alternative energy generating patterns(2)

38. Alternative energy generating patterns(3)

39. Alternative energy generating patterns(4)

40. Energy/carbon classes of organisms

41. Chlorophyll a and bacteriochlophyll a(3)

42. Comparison of reaction centers of anoxyphototrophs