Isolation, purification and characterization of novel uricase from Delftia tsuruhatensis IICT-RSP4

A novel uricase (urate oxidase; EC 1.7.3.3), produced in the absence of uric acid induction, was isolated and characterized from the bacterial strain IICT-RSP4 and identified through 16S rRNA sequencing and whole-genome analysis. Among the tested conditions, dextrose and urea were found to be the most effective carbon and nitrogen sources, respectively, for enhanced uricase production. Enzyme purification was performed via ammonium sulfate precipitation followed by size-exclusion chromatography coupled with Fast Protein Liquid Chromatography (FPLC). Molecular characterization of enzyme was performed by SDS–PAGE and ESI–LC–MS. The results showed that the uricase producing strain IICT-RSP4 was identified as Delftia tsuruhatensis IICT-RSP4. The highest enzymatic activity was achieved under optimal conditions of pH 7.0 and a temperature of 30 °C and calculated as 20.72 U/ml. The purification resulted an increase in enzyme activity from 1.7 to 40 U/ml and revealed a molecular weight of approximately 36 kDa. Biochemical profiling of enzyme indicated an optimal activity at pH 9.0 and 30 °C in the presence of cobalt ions. These findings suggest that D. tsuruhatensis IICT-RSP4 is a promising microbial source of uricase with potential biotechnological applications.