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MP4. Regulation of Metabolic Pathways: How Is It Regulated?

  • Page ID
    4263
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    Exquisite mechanisms have evolved that control the flux of metabolites through metabolic pathways to insure that the output of the pathways meets biological demand and that energy in the form of ATP is not wasted by having opposing pathways run concomitantly in the same cell.

    Enzymes can be regulated by changing the activity of a preexisting enzyme or changing the amount of an enzyme.

    A. Changing the activity of a pre-existing enzyme: The quickest way to modulate the activity of an enzyme is to alter the activity of an enzyme that already exists in the cell. The list below, illustrated in the following figure, gives common ways to regulate enzyme activity

    1. Prod_Feedback Inhib
      1. Figure: Regulation of the Activity of Pre-existing Enzymes

        Reg Exist Enz Act

        Jmol: Erk2 -Structural Comparison of phosphorylated and dephosphorylated enzyme

        B. Changing the amount of an enzyme: Another and less immediate but longer duration method to modulate the activity of an enzyme is to alter the activity of an enzyme that already exists in the cell. The list below, illustrated in the following figure, shows way in which enzyme concentration is regulated.

        1. Reg Enz Amount

    This page titled MP4. Regulation of Metabolic Pathways: How Is It Regulated? is shared under a CC BY-NC 3.0 license and was authored, remixed, and/or curated by Chris Schaller.

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