metabolism of glycogen - core.ac.uk · metabolism of glycogen describe the synthesis and breakdown...

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Dr. Mirhashemi

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Citric acid

cycle

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Biosynthetic roles of The citric acid cycle

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Metabolism of Glycogen

Describe the synthesis and breakdown of glycogen and how

the processes are regulated in response to hormone action.

Describe the various types of glycogen storage diseases

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Glycogen structure

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Electron micrograph of a liver cell

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Glycogen Is Synthesized and Degraded

by Different Pathways

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UDP-glucose is an activated form of glucose

UDP-glucose is synthesized from glucose 1-phosphate and

uridine triphosphate (UTP) in a reaction catalyzed by

UDP-glucose pyrophosphorylase.

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Glycogen synthase catalyzes the transfer of glucose

from UDP-glucose to a growing chain.

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A branching enzyme forms a-1,6 linkages

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The biosynthesis of glycogen

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Cross section of a glycogen molecule

Glucose 6-phosphate +ATP + Glycogen +

H2O Glycogen + ADP + 2 Pi

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Steps in glycogenolysis

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Glycogen Breakdown and Synthesis Are

Reciprocally Regulated

The principal enzymes controlling glycogen metabolism: glycogen phosphorylase and glycogen synthase.

Phosphorylation of glycogen phosphorylase increases its activity.

phosphorylation of glycogen synthase reduces its activity.

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Some types of Glycogen-storage diseases

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