2 BC922 lec11 metab Glycolysis web.ppt - zilouei.iut.ac.ir fileFeed-forward activation • Metabolite early in the pathway activates an enzyme further down the pathway Catabolism produces

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Anabolism and catabolism

Metabolism

Forms of metabolic pathways

Linear Cyclic

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• Single-step vs multi-step pathways

• A multistep enzyme pathway releases energy in smaller amounts that can be used by the cell

Feedback inhibition

• Product of a pathway controls the rate of its own synthesis by inhibiting an early step (usually the first “committed” step (unique to the pathway)

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Feed-forward activation

• Metabolite early in the pathway activates an enzyme further down the pathway

Catabolism produces compounds for energy utilization

(1) Nucleoside triphosphates (e.g. ATP)

(2) Reduced coenzymes (NADH, FADH2,)

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Thioesters Have High Free Energies of Hydrolysis

• Thioesters are energy-rich compounds (10.22)

• Acetyl CoA has a ∆Go’ = -31 kJ mol-1 (10.23)

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The pathway for catabolism of

glucose

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Glycolysis

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Glycolysis summary

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Glycolysis in summary

How many ATP and how many e-carriers are produced?

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