UMP kinase or uridylate kinase is essential for biosynthesis of nucleic acid. It catalyzes the ATP-dependent phosphorylation of UMP into UDP. 

UMP   +   ATP      =           UDP    +    ADP

UMP kinase is an attractive antibacterial target.  The UMP kinase assay is based on measurement of ADP generated from the kinase reaction.  The assay is fluorescence-based and can be carried out using regular black 96-well or 384-well plates or micro-cuvettes.  

E. coli UMP Kinase Assay Kit Plus-100 (Catalog number: UMK100KE)

E. coli UMP Kinase Assay Kit Plus-500 (Catalog number: UMK500KE)