Ground-state electronic destabilization via hyperconjugation in aspartate aminotransferase.
نویسندگان
چکیده
Binding isotope effects for l-aspartate reacting with the inactive K258A mutant of PLP-dependent aspartate aminotransferase to give a stable external aldimine intermediate are reported. They provide direct evidence for electronic ground-state destabilization via hyperconjugation. The smaller equilibrium isotope effect with deazaPLP-reconstituted K258A indicates that the pyridine nitrogen plays an important role in labilizing the Cα-H bond.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 134 20 شماره
صفحات -
تاریخ انتشار 2012