EXPRESSION AND PURIFCATION OF PP5C FOR DRUG DESIGN

Abstract

Protein phosphatase 5 (PP5) is a serine/threonine phosphatase (PSP) that participates in the cellular response to stress, particularly DNA damage. While participation in this pathway is unique to PP5, the structure of the enzyme is very similar to other members of the PSP family. The similarity between these phosphatases makes designing specific inhibitors for any one member of the PSP family exceedingly difficult. It is with this end goal in mind that I have chosen to express and characterize the catalytic domain of PP5 (PP5c) in order to examine the protein for differences that would allow for drug design. This characterization focused on activity and stability through the of pNPP assays and differential scanning fluorimetry, respectively.. These assays were done with protein phosphatase 1 (PP1) as a comparison and it was found that PP5c is most stable under different buffer conditions and has a lower activity level than PP1.