Metabolism - Handout 2 Flashcards
Catabolic reactions
Breakdown reactions that release energy.
Anabolic reactions
Building reactions that require energy.
What is oxidation? Is energy produced or required for these type of recations?
- The loss/removal of electrons (becomes lower in energy)
- Produces energy.
Mnemonic: OIL RIG (Oxidation Is Loss, Reduction Is Gain)
What is reduction? Is energy produced or required?
- Gain of electrons (becomes higher in energy)
- Requires energy
What is phosphorylation?
Gain of a phosphate group.
Ex. ADP → ATP
List the 3 types of phosphorylation that generate ATP, give an example of each.
- Substrate level phosphorylation - ex. glycolysis
- Oxidative phosphorylation - ex. electron transport chain
- Photophosphorylation - ex. use of light trapping pigments such as chlorophyll (don’t focus on this type of phosphosphorylation)
Explain the overall function of glycolysis (aka Embden Meyerhof Parnas - EMP pathway).
- Substrate level phosphorylation.
- Produces ATP.
- Reduces NAD+ to NADH.
- Oxidizes glucose to pyruvic acid.
- In respiration, pyruvic acid is converted to the first reactant in Kreb’s cycle.
Explain the overall function of Kreb’s cycle.
- Produces ATP.
- Reduces NAD+ to NADH.
- Reduces FADH to FADH2.
- NADH and FADH2 carry electrons to the ETC
Explain the overall function of the electron transport chain (ETC).
- Use the energy from electrons to produce lots of ATP
- This occurs via oxidative phosphorylation
Explain the overall function of fermentation.
- Incorporate the pyruvic acid and elcetrons carried by NADH from glycolysis into fermentation end products (i.e. acids and alcohol)
- Ineffeciently produces ATP and NAD+
What anerobic oxidation reaction occurs in glycolysis?
Glucose is oxidized to pyruvic acid.
What is the reduction reaction in glycolysis?
2 NAD+ are reduced to NADH
How many net ATP are produced by glycolysis.
2 ATP are produced by substrate-level phosphorylation.
What are the functions of the pentose phosphate pathway?
- It allows the breakdown of of pentoses.
- It produces important intermediate pentoses used in synthesis of nucleic acids, glucose from carbon dioxide in photosynthesis, and some amino acids
- Examples: Bacillus subtilis, E. coli, and Enterococcus faecalis
What is the most common glycolysis alternative?
The pentose phosphate pathway.
What is another name for the pentose phosphate pathway?
The hexose monophosphate shunt.
How many ATP per cycle are produced in the pentose phosphate pathway?
1 ATP/cycle
What pathway can run without glycolysis?
The Entner-Doudoroff pathway.
Give a clinically relevant example of a microbial genus that uses the Entner-Doudoroff pathway.
Pseudomonas
What are the products of the Entner-Doudoroff pathway per molecule of glucose?
2 NADPH and 1 ATP
What are the two other common names for Krebs cycle?
- Tricarboxylic acid (TCA) cycle
- Citric acid cycle
What are the net products of Krebs cycle, per 2 acetyl CoA?
- 4 CO2
- 6 NADH
- 2 FADH2
- 2 ATP
