Substrate ambiguity
Jan 31, 2026
Substrate ambiguity is a biological phenomenon where a single enzyme can interact with and catalyze reactions for multiple different substrates, rather than being specific to just one.
This contrasts with the classical “lock-and-key” model of enzymes, which assumed strict one-to-one binding relationships between enzymes and substrates.
Substrate ambiguity represents the actual behavior of some enzymes in nature, even though it may appear ambiguous to an observer expecting more narrow binding specificity.
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