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key concept

8.4

Enzymes Bring Substrates Together so Reactions Readily Occur

During and after the formation of the enzyme–substrate complex, chemical interactions occur. These interactions contribute directly to the breaking of old bonds and the formation of new ones. In catalyzing a reaction, an enzyme may use one or more strategies.

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  • Several different mechanisms enable enzymes to speed up chemical reactions.

  • An enzyme may undergo a change in shape called induced fit as the result of binding its substrate.

  • Many enzymes require additional chemical partners to catalyze a chemical reaction.

  • The concentration of substrate influences the rate of an enzyme-catalyzed reaction.