TRIOSEPHOSpJiATE ISOMERASE AND PROLINE RACEMASE: REVELATION OF REACTION ENERGETICS
نویسنده
چکیده
II. Triosephosphate Isomerase ....................................... .432 A. Isotopic Labeling to Reveal Mechanism ...................... .432 B. Isotope Effects to Reveal Reaction Energetics ................. .433 1. Transfer Experiments ................................. .434 2. Discrimination Experiments ............................ .435 3. Exchange vs. Conversion Experiments .................. .435 4. Deuterium Kinetic Isotope Effects ...................... .436 5. Free Energy Profile for the Catalyzed Reaction .......... .438 C. Detection and Kinetic Characterization of Unliganded Enzymic Forms .............................. « •••••••••••••••••••••• 438 D. Reaction Energetics of Active-Site Mutants ................... .440 1. Replacing the Active-Site Glutamate with Aspartate: A Change in Reaction Energetics ....................... .440 2. Replacing the Active-Site Histidine with Glutamine~ A Change in Reaction Mechanism ...................... .441
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