Dihydropyrimidinase is an enzyme that plays a crucial role in the catabolism of pyrimidines, specifically by catalyzing the hydrolytic ring opening of dihydropyrimidines to N-carbamyl-β-amino acids. Deficiencies in this enzyme can lead to disorders such as dihydropyrimidinuria, characterized by the accumulation of dihydropyrimidines in the urine.