The histidine 115-histidine 134 dyad mediates the lactonase activity of mammalian serum paraoxonases.

@article{Khersonsky2006TheH1,
  title={The histidine 115-histidine 134 dyad mediates the lactonase activity of mammalian serum paraoxonases.},
  author={Olga Khersonsky and Dan S. Tawfik},
  journal={The Journal of biological chemistry},
  year={2006},
  volume={281 11},
  pages={7649-56}
}
Serum paraoxonases (PONs) are calcium-dependent lactonases that catalyze the hydrolysis and formation of a variety of lactones, with a clear preference for lipophilic lactones. However, the lactonase mechanism of mammalian PON1, a high density lipoprotein-associated enzyme that is the most studied family member, remains unclear, and other family members have not been examined at all. We present a kinetic and site-directed mutagenesis study aimed at deciphering the lactonase mechanism of PON1… CONTINUE READING