Urea-induced Denaturation of Human Phenylalanine Hydroxylase*

@article{Kleppe1999UreainducedDO,
  title={Urea-induced Denaturation of Human Phenylalanine Hydroxylase*},
  author={Rune Kleppe and Kathrin Uhlemann and Per Morten Knappskog and Jan Haavik},
  journal={The Journal of Biological Chemistry},
  year={1999},
  volume={274},
  pages={33251 - 33258}
}
Human phenylalanine hydroxylase was expressed and purified from Escherichia coli as a fusion protein with maltose-binding protein. After removal of the fusion partner, the effects of increasing urea concentrations on enzyme activity, aggregation, unfolding, and refolding were examined. At pH 7.50, purified human phenylalanine hydroxylase is transiently activated in the presence of 0–4 m urea but slowly inactivated at higher denaturant concentrations. Intrinsic tryptophan fluorescence… Expand
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