bacterial metabolism n.
Skip this Video
Loading SlideShow in 5 Seconds..
Bacterial Metabolism PowerPoint Presentation
Download Presentation
Bacterial Metabolism

Loading in 2 Seconds...

play fullscreen
1 / 46

Bacterial Metabolism - PowerPoint PPT Presentation

  • Uploaded on

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. Overview of cell metabolism. Bacterial Metabolism. Autotroph:

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

Bacterial Metabolism

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
bacterial metabolism
Bacterial 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

bacterial metabolism1
Bacterial Metabolism
  • Autotroph:

Photosynthetic bacterial

Chemoautotrophic bacteria

  • Heterotroph:




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

(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


6CO2 + 6H2O -----> C6H12O6 +6O2

(Light and chloroplast)

bacteria photosynthesis
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


v. Similar CO2 fixation

vi. Only has cyclic photophosphorylation

how the bacteria synthesize nadph
How the Bacteria synthesize NADPH
  • Grow in the presence of the H2 gas

H2 + NADP+ ------------- NADPH2


  • Reverse the electron flow in the e- transport chain


S + NADP+-------- SO4-2 + NADPH2

Succinate Fumarate

  • Simple non-cyclic photosynthetic e- flow
photosynthetic bacteria
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
  • 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.)
aerobic respiration
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

aerobic respiration1
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

Kreb cycle:

Pyruvate + 4NAD + FAD ----->


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 + 6O2 ------> 6CO2 + 6H2O + 38 ATP

anaerobic respiration
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.

  • 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

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