Other Carbohydrates

Question 1

why is NADPH important

Answer 1

It is important for the synthesis of reducing equivlents, NADPH, for glutathione (GSH) reduction

Question 2

what is the first step of the pentose phosphate pathway?

Answer 2

G6P is converted into 6 phosphoglucono alpha lactone using Glucose-6- dehydrogenase

Question 3

What occurs when you have a deficiency in G6P dehydrogenase

Answer 3

you do not get the PPP and have no NADPH made to protect the cell

Question 4

G6P dehydrogenase

Answer 4

Converts G6P to 6 phosphoglucono delta lactone
most common deficincy - cannot make NADPH
X-linked
jaundice
get hemolytic anemia due to the increased ROS. Will see heinz bodies

Question 5

What are the names of the enzymes that transfer carbons in the PPP

Answer 5

transketolase and transaldolase

Question 6

what is the enzyme that uses Thiamine as a cofactor?

Answer 6

transketolase

Question 7

Where is the second NADPH of the PPP generated?

Answer 7

between 6-phospho gluconate and ribulose 5P. It uses the 6-phosphogluconate dehydrogenase enzyme. It is a decarboxylation rxn.

Question 8

6 phospho gluconate dehydrogenase

Answer 8

gain an NADPH in the PPP by convering 6 phosphpo gluconate to ribulose 5P

Question 9

Fructose Metabolism takes place

Answer 9

in the liver

Question 10

what is the rate limiting step of fructose breadown?

Answer 10

Aldolase B, converion of F1P to glycerol and DHAP

Question 11

between F1P and F16BP which is preferntially cleaved by aldolase B?

Answer 11

F16BP

Question 12

path way of fructose break down?

Answer 12

Fructose becomes F1P using fructokinase or F6P using hexokinase.F6P is broken down into F16BP using Phosphofructokinase. Using aldolase B, F1P is broken down into DHAP and Glyceraldehyde and F16BP is borken into DHAP and G3P

Question 13

essential fructosuria

Answer 13

not bad. When you have a defect in

Question 14

action of phosphofructokinase

Answer 14

convert F6P to F16BP

Question 15

deficiency of psosphofructokinase

Answer 15

essential frucosuria

Question 16

deficiency in aldolase B

Answer 16

hereditary fructose intolerence.

Question 17

hereditary fructose intolerance

Answer 17

deficiency in aldolase B. Trap phosphate stores in F1P, which stops OxPhos –> liver failure.

Question 18

where does sorbitol come from?

Answer 18

It comes from the break down of glucose via aldol reductase. Occurs during hyperglycemia - glucose takes this alternative pathway. capacity of hexokinase is exceeded

Question 19

what does sorbitol do?

Answer 19

diabetic neuropathy!

Question 20

how do you get fructose from glucose?

Answer 20

convert to sorbitol, convert sorbitol to fructose.

Question 21

why do we need to make fructose?

Answer 21

so the spermies can swim! Sperm use fruotse for major fuel source

Question 22

Classic Galactasemia

Answer 22

When you have a problem with the Gal 1-P urididyl transferase which converts Gal-1-p to Glu 1P

Question 23

pathway of making Lactose

Answer 23

G1p –> UDP Glu–> UDP Gal –> Lactose.

Question 24

what enzyme converts UDP Gal –> Lactose

Answer 24

lactose synthase

Question 25

protein B of lactose synthase is made in response to

Answer 25

prolcatin