BCHM IV: Chap. 13

Glycogenolysis

Breaks down glycogen

Glycolysis

Breaks down glucose by splitting monosaccharides

Glucose

Very versatile, easily stored and quickly released, rich in potential energy, and is the sole source of energy in many mammalian tissues and cell types.

Is glycolysis anaerobic or aerobic?

Both

How many steps are in the first phase (investment/preparatory phase) for glycolysis

Five which consumes energy

Step one of glycolysis

Phosphate is added onto C6 because it is the most accessible carbon with a hydroxyl where the phosphate is added because it is taken from the ATP. Mg will also neutralize the negative charge of the phosphate and hexokinase will then catalyze the reaction via the induced fit model.

Step two of glycolysis

Isomerization reaction where phosphoglucose isomerase will reversibly make a six sugar ring into a five sugar ring and establish another CH₂OH. Its free energy is a very small positive value.

Step three of glycolysis

Phosphofructiokinase (PFK1) will phosphorylate fructose-6-phosphate to fructose 1,6 bisphosphate and is irreversible and is the slowest step.

Which step in glycolysis is the first committed step and is the second priming reaction with the second input of ATP with Mg

Step three of glycolysis

PFK 2

Takes ATP to crete fructose 2,6 bisphosphate

How ADP will regulate PFK1

Speed things up in bacteria whereas phosphoenolpyruvate will slow down the process.

Step four of glycolysis

When aldolase catalyzes an alcohol to an aldehyde

Why can’t dihydroxyacetonephosphate (DHAP) be broken down in step four?

It is a ketone

Step five of glycolysis

Triose phosphate isomerase will flip the position of the carbonyl and hydroxyl groups

What makes triose phosphate isomerase (TPI) the perfect enzyme?

The loop it has allows it to be extremely efficient.

What does step five of glycolysis yield

Two glyceraldehyde-3-phosphate molecules

What is the input and the product for the first phase of glycolysis?

Input: -2 ATP and one glucose

Product: two glyceraldehyde-3-phosphates

The second phase (payoff) includes what steps and does what?

Includes steps 6-10 and produces energy

Step 6 of glycolysis

G3P is oxidized and the hydrogen attached to the carbonyl group will be replaced with a phosphate via G3P from taking a P from the reactants and will reduce NAD+ to NADH.

What are the products of step six for glycolysis

Two 1,3-bisphosphoglycerate molecules and two NADHs

Is step six of glycolysis (ir)reversible?

Reversible

What two processes allows step six of glycolysis to keep going?

Oxidative phosphorylation and fermentation

Step seven of glycolysis

Phosphoglycerate kinase (transferase enzyme) will catalyze