Consider an enzyme that catalyzes the ?-elimination reaction below via an enolate intermediate (shown). You know that the active site contains a glutamate residue, a histidine residue, and a Zn2+ ion that are all important for catalysis. Propose an acid/base mechanism for this hypothetical enzyme-catalyzed reaction. Hint: alpha protons are more acidic than normal alkyl protons when an enolate can form.
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The histidine residue can act as a base and abstract the alpha proton from the substrate, forming an enolate intermediate. Show moreā¦
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