Structure-based design of a hyperthermostable AgUricase for hyperuricemia and gout therapy.Arthrobacter globiformis Uricase (AgUricase) is a homotetrameric uricase with the potential for therapeutic use in treating hyperuricemia-related diseases.  To achieve sufficient therapeutic effects, it is essential for this enzyme to have high thermostability and long half-life in physiological condition.  To improve the thermostability of this enzyme, we introduced a series of cysteine pair mutations into the AgUricase subunits based on its structural model and studied the thermostability of the mutant enzymes with introduced disulfide bridges.  We introduced an additional intersubunit K244C-C302 disulfide bond based on the crystal structure of the K12C-E286C mutant and confirmed that this additional disulfide bond further stabilized the flexible C-terminal loop and improved the thermostability of the enzyme.  Our studies suggest that the introduction of disulfide bonds into proteins is a potential strategy for enhancing the thermostability of multimeric proteins for medical applications.
THERM