MicrobialMetabolism.txt

• No energy is never created nor destroyed, only moved around.
• They extract energy that is already present in the bonds of the nutrients.

It is a reaction that salvages electrons (and the energy associated with them) released from the breaking of nutrient bonds.

How energy is banked.

Oxidation is the removal of electrons from a molecule, and is always coupled with a Reduction reaction.

Reduction is the gaining of electrons, and are always coupled with Oxidation.

• This is the removal of hydrogen atoms.
• Biological oxidation reactions are often dehydration reactions.

NAD+ + 2H++2e- = NADH+H+

This is energy extracted in the form of electrons

• ATP
• ATP has "high energy" or unstable bonds which allows the energy to be released quickly and easily

• Substrate-level phosphorylation
• Oxidative phosphorylation
• Photophosphorylation

Generation of ATP when a high energy phosphate is transferred directly to ADP from a phosphorylated substrate.

Electrons are transferred from organic compunds through a series of electron carriers to O2 or other oxidized inorganic or organic molecules.

This occurs in photosynthetic cells, the light causes chlorophyll to give up electrons

• By the oxidation of..
• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals
• Water

• Cellular respiration
• Fermentation

Both start with Glycolysis

• Glycolysis
• Intermediate step
• TCA cycle (Kreb's cycle)
• Electron Transport Chain

Glucose is oxidized to pyruvic acid with ATP and NADH produced

Pyruvic acid is converted to acetyle-CoA with NADH produced

Acetyl CoA is oxidized to CO2 with ATP, NADH and HADH2 produced

NADH and HADH2 are oxidized through a series of redox reactions and a considerable amount of ATP is produced

10 steps

• Used simultaneously with glycolysis (several intermediates can reenter glycolysis)
• Breakdown of 5-carbon sugars(pentoses) as well as glucose
• Produces important intermediates in the synthesis of, Cucleic acids, glucose from Co2 and certian amino acids
• Produces NADPH for anabolic reaction
• Yealds only 1 atp per glucose

• Bacteria can metabolize glucose without glycolysis or pentose phosphate pathway.
• Produces 2 NADPH and 1 ATP/glucose
• Used by obligate aerobes such as Pseudomonas Spp.

• After glucose is broken down to pyruvic acid, it can be channeled into either Fermentaion or
• Cellular respiration.
• Aerobic respiration or anaerobic respiration

• Tricarboxylic acid (TCA) cycle
• Kreb's cycle or citric acid cycle
• A large amount of potential energy stored in acetyl CoA is released by a series of redox reactions that transfer electrons to the electron carrier coenzymes (NAD+ and FAD)

• Used in the intermediate step
• Pyruvic acid is converted to a 2-carbon compound (decarboxylation)
• The 2 carbon acetle group then combines with Coenzyme A through a high energy bond
• NAD+ is reduced to NADH

• Glucose is split and oxidized through a ten step pathway to two molecules of pyruvic acid
• Net gain of 2 ATP molecules, 4 from energy phase(by substrate level phosphorylation) mins 2 from preparatory phase
• 2 NADH molecules produced (will be used to make more ATP)
• Pyruvic acid can now undergo either Fermentation or respiration

• Pathway # of Steps Energy used Energy Gained Energy forms
• Glycolysis 10 2 ATP 4 ATP, 2 NADH ATP, NADH
• Intermediate 1 0 2 NADH NADH
• Kreb's 9 0 2 ATP, 6NADH, 2 FADH ATP, NADH, FADH

Per per glucose molecule