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What does it mean when an enzyme is saturated with substrate?
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Protein
The molecular structure of a peptide (a small protein) consists of a sequence of amino acids.
When an enzyme is saturated with substrate, it means that all of the available active sites on the enzyme molecules are occupied and actively engaged in catalyzing a reaction.12
At this state, the reaction has reached its maximum velocity. Because every active site is filled, the rate of the reaction is no longer dependent on the concentration of the substrate; instead, it is limited by the speed at which the enzyme can convert the substrate into product and release it to free up the active site for another molecule.23