Sandbox Reserved 1852: Difference between revisions
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==Applications== | ==Applications== | ||
The CE20 model is the most efficient Diels-Alderase yet, surpassing many other biological (antibody) and artificial (ribozyme, metalloenzyme) attempts at catalyzing the Diels-Alder reaction.<ref name="Preiswerk"/> Even then, the CE20 model has a catalytic efficiency value at least 4 orders of magnitude lower than the preferred values seen in any moderately-efficient natural enzymes catalyzing various reactions. This demonstrates the innate slowness of the Diels-Alder reaction.<ref name="Preiswerk"/> | The CE20 model is the most efficient Diels-Alderase yet, surpassing many other biological (antibody<ref name="Gouverneur"/>) and artificial (ribozyme, metalloenzyme) attempts at catalyzing the Diels-Alder reaction.<ref name="Preiswerk"/> Even then, the CE20 model has a catalytic efficiency value at least 4 orders of magnitude lower than the preferred values seen in any moderately-efficient natural enzymes catalyzing various reactions. This demonstrates the innate slowness of the Diels-Alder reaction.<ref name="Preiswerk"/> | ||
Though the rate of product formation using this enzyme is not significantly different from that found when reactants reflux free in solution (about 10 substrate molecules/hour),<ref name="Preiswerk"/> the Diels-Alderase shows a vast improvement in product stereoselectivity. When refluxed in a room temperature aqueous solution containing the necessary substrates, the enzyme catalyzed an over 90% conversion rate, producing only the 3R,4S endo cyclohexane product isomer. By comparison, refluxing the substrates free in toluene for a similar duration of time yields a racemic (66:34) mixture of endo and exo products. It is primarily for these stereoselective benefits that this enzyme is valuable for synthetic purposes. <ref name="Preiswerk"/> | Though the rate of product formation using this enzyme is not significantly different from that found when reactants reflux free in solution (about 10 substrate molecules/hour),<ref name="Preiswerk"/> the Diels-Alderase shows a vast improvement in product stereoselectivity. When refluxed in a room temperature aqueous solution containing the necessary substrates, the enzyme catalyzed an over 90% conversion rate, producing only the 3R,4S endo cyclohexane product isomer. By comparison, refluxing the substrates free in toluene for a similar duration of time yields a racemic (66:34) mixture of endo and exo products. It is primarily for these stereoselective benefits that this enzyme is valuable for synthetic purposes. <ref name="Preiswerk"/> | ||
