Fructose Metabolism

Question 1

What is the first step in fructose metabolism?

Answer 1

Fructose -> Fructose-1-Phosphate

Question 2

Which enzyme converts Fructose to Fructose-1-Phosphate?

Answer 2

Fructokinase

Question 3

What does the suffix -kinase mean in an enzyme?

Answer 3

A phosphate group gets added

Question 4

What does Fructokinase do to fructose?

Answer 4

Adds a phosphate group to it

Question 5

Which enzyme works on Fructose-1-Phosphate?

Answer 5

Aldolase B

Question 6

Aldolase B can convert Fructose-1-Phosphate into either:

Answer 6

1) Glyceraldehyde
2) DHAP

Question 7

Both Glyceraldehyde and DHAP are converted into:

Answer 7

Glyceraldehyde-3-Phosphate (G3P)

Question 8

Glyceraldehyde-3-Phosphate (G3P) enters which metabolic process?

Answer 8

Glycolysis

Question 9

Clinical symptoms of Fructokinase deficiency?

Answer 9

1) Fructosemia
2) Fructosuria
(Benign)

Question 10

Mode of inheritance of Fructokinase deficiency?

Answer 10

Autosomal recessive

Question 11

What accumulates in Fructokinase deficiency?

Answer 11

Fructose

Question 12

Which enzyme is deficient in Hereditary Fructose Intolerance?

Answer 12

Aldolase B

Question 13

What accumulates in Hereditary Fructose Intolerance (Aldolase B Deficiency)?

Answer 13

Fructose-1-Phosphate

Question 14

Fructokinase requires a phosphate group. Where does it get it from?

Answer 14

ATP

Question 15

What are the findings in Hereditary Fructose Intolerance (Aldolase B Deficiency)?

Answer 15

1) DECREASED ATP!!!
2) DECREASED Gluconeogenesis
3) DECREASED Glycogenolysis
4) Hypoglycemia

Question 16

What is the treatment for Hereditary Fructose Intolerance (Aldolase B Deficiency)?

Answer 16

Decrease fructose, glucose, and sucrose

Question 17

Clinical picture of someone becoming hypoglycemic after eating fruit, honey, or juice. What do they most likely have?

Answer 17

Hereditary Fructose Intolerance (Aldolase B Deficiency)