Biochemistry 514 Exam Ii: Glycogen Breakdown

Front 1

Glycogen Phosphorylase

Back 1

-Glycogen + Pi---> glucose 1-P + glycogen (minus one sugar)
-Sterically inhibited 4 sugars away from branching point
-Phosphorolysis
-alpha 1,4-linkages

Front 2

Debranching enzyme-2 activities

Back 2

-Transferase activity, takes off most of the branch and moves it to the end of the molecule.
1. Transferase: removes branches
2. Alpha-1,6 glucosidase: removes last glucose molecule (breaks alpha-1,6) with water

Front 3

Glucose 1-P--->glucose-6-P

Back 3

Phosphoglucomutase

Front 4

Glucose-6-P--->glucose--->blood

Back 4

Glucose-6-Phosphatase

Front 5

Glycogen ---> Glucose-1-P

Back 5

Glycogen phosphorylase

Front 6

Regulation of Glycogen Breakdown

Back 6

AMP +
ATP -
Glucose 6-P -
Ca +2 +

Front 7

Hormonal control

Back 7

Epinephrine + glucagon--->adenylate cyclase (ATP)--->Cyclic AMP--->protein kinase--->Phosphorylase Kinase

Front 8

Inactive, unphosphorylated, regulated Glycogen Phosphorylase --->Inactive, phosphorylated, unregulated Glycogen Phosphorylase

Back 8

Phosphorylase Kinase

Front 9

Glycogen Phsophorylase (inactive, phosphorylated, unregulated)--->Glycogen Phosphorylase (active, phosphorylated, unregulated)

Back 9

Glucose

Front 10

Glycogen Synthase (active, unphosphorylated) ---> Glycogen Synthase (inactive, phosphorylated)

Back 10

Protein Kinase

Front 11

Glycogen Synthase (inactive phosphorylated) ---> Glycogen Synthase (active, unphosphorylated )

Back 11

Phosphatase

Front 12

Glycogen Phosphorylase (inactive, unphosphorylated) regulation

Back 12

AMP +
ATP -
GTP -

Front 13

Glycogen Phosphorylase (active, phosphorylated)regulation

Back 13

Insensitve to cellular effectors, except glucose -

Front 14

Glycogen Synthase (inactive, phosphorylated)

Back 14

G-6-P +

Front 15

Von Gierke's Disease

Back 15

Deficient in glucose 6-Phosphatase (can't break down glycogen)
-Increased amounts of glycogen in liver
-Liver enlargment, hypoglycemia, ketosis, hyperuricemia, hyperlipemia
-correct by giving simple sugars

Front 16

Pompe's Disease

Back 16

Deficient in alpha 1,4-glucosidase (which removes end glucose molecules from glucose stores)
-Increases amount of glycogen
-Cardiorespiratory failure, death by age 2

Front 17

Cori's Disease

Back 17

-Deficient in amylo-1,6-glucosidase (debranching enzyme)
-Increase amt of glycogen, but shorter outer branches
-Still have some access to glycogen stores
-Milder form of Von Gierke's Disease

Front 18

Andersen's Disease

Back 18

-Deficient in branching enzyme (alpha 1,2 to alpha 1,6)
-Normal amt of glycogen, very long single chains (no branching)
-Inflammatory response bc thinks long chains are a foreign substance
-Cirrhosis of liver, death by age 2

Front 19

McArdle's Disease

Back 19

-Defective Phosphorylase
-Glycogen normal, but increased amts of it
-Limited ability to perform strenuous exercise bc of painful muscle cramps
-In muscle

Front 20

Hers' Disease

Back 20

-Defective Phosphorylase
-Increase amount of glycogen
-in liver

Front 21

Type VIII

Back 21

-Defective phosphorylase kinase (turns tense structure into tense phosphorylate form)
-Increased amt of glycogen
-Mild liver enlargment, mild hypoglycemia
-Sex-linked trait