Glycolysis Flashcards

1
Q

Insulin stimulates what enzyme in glycolysis

A

Glucokinase locks glucose in the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

AMP stimulates what enzyme in glycolysis

A

PFK-1 makes fructose 1,6 bisphophate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What has a negative effect on PFK-1

A

Citrate ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the last step of glycolysis

A

Phosphoenolpyruvate –> Pyruvate via pyruvate kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Pyruvate kinase deficiency

A

Partial enzyme defect Hemolytic anemia increased 2,3-BPG no Heinz bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

RBC are capable of only doing

A

glycolysis HMP shunt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why does pyruvate kinase deficiency get hemolytic anemia

A

can’t do glycolysis to get ATP to power cation pumps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In methemoglobin iron is in the

A

+3 state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In hemoglobin iron is in the

A

+2 state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

RBC need the NADH from glycolysis to

A

change methemoglobin back to hemoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

RBC use the HMP shunt bc

A

to make NADPH an antioxidant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Increase of 2,3 BPG will cause

A

O2 sat curve to shift to the right decreased O2 affinity for Hb more O2 unloading off Hb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

After a high carb meal what will you see in glycolysis

A

Increased ATP Decreased PFK-1 decreased glycolysis (unless overrides by PFK-2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the first enzyme in glycolysis

A

Hexokinase glucokinase (liver only)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does PFK-2 do

A

Fructose-6P –> Fructose 2, 6 P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does PFK-1 do

A

Fructose-6P –> Fructose 1,6 bis P

17
Q

What is the role of Fructose 2,6-P

A

Will overcome any inhibition of PFK-1 by ATP or citrate to make Fructose 1,6-BP Complete glycolysis to make pyruvate to do FA synthesis ONLY IN LIVER

18
Q

What stimulates PFK-2

19
Q

Insulin stimulates what enzymes in glycolysis

A

hexokinase PFK-2 PFK-1 indirectly

20
Q

What inhibits PFK-2

A

Glucagon indirectly inhibits PFK-1 in liver

21
Q

In the presence of O2 how is NADH recycled to NAD+ to continue glycolysis

A

in the mitochondria electrons from pyruvate taken off and put on O2 to make water Pyruvate goes to mitochondria –> acetyl-coA via pyruvate DH to go into TCA cycle makes more ATP and CO2

22
Q

Without O2, how is NADH recycled to NAD+ to continue glycolysis

A

lactate DH converts pyruvate to lactate in the cytoplasm

23
Q

Which glycolysis enzymes require ATP

A

hexokinase/glucokinase

PFK-1

24
Q

Which glycolysis enzymes make ATP

A

Phosphoglycerate kinase (1,3-BPG to 3-PG)

Pyruvate kinase (PEP to pyruvate)

25
Which is induced by insulin, glucokinase or hexokinase
glucokinase
26
Which has a higher Km (low affinity), hexokinase or glucokinase
Glucokinase
27
Which has a higher Vmax (increased capacity), hexokinase or glucokinase
Glucokinase
28
Which has feedback inhibition by G6P, hexokinase or glucokinase
hexokinase
29
Biochemical basis in fasting state
1. Increased glucagon will increasing cAMP 2. increase protein kinase A 3. **increase in FBPase-2** 4. decrease PFK-2 5. **less glycolysis, more gluconeogenesis**
30
Biochemical basis of fed state
1. increase insulin will decrease cAMP 2. decrease protein kinase A 3. decrease FBPase-2 4. **increase PFK-2** 5. **more glycolysis**, less gluconeogenesis
31
Pyruvate DH is active in what state
fed state
32
Pyruvate DH is activated by
increase NAD+/NADH ratio, ADP, Calcium
33
what is PDH complex deficiency
Build up of pyruvate that gets shunted to lactate (via LDH) and alanine (via ALT)
34
Characteristics of PDH deficiency
1. neurologic defects 2. **lactic acidosis** 3. increase **serum alanine** in infancy
35
How to treat PDH deficiency
increase intake of ketogenic nutrients * high fat content * increase leucine and lysine