SensiStain Anti-Thymidylate Synthase Antibody detects for the thymidylate synthase enzyme which functions to catalyze the conversion of deoxyuridine monophosphate (dUMP) to 2'-deoxythymidine-5'-monophosphate (dTMP), an essential precursor in DNA biosynthesis processes. It is a key enzyme which has been a target for chemotherapy.