Beta-ureidopropionase (UPB1)

The BUP1 open reading frame of 1,152 bp corresponds to a protein of 384 amino acids with a calculated molecular mass of 43 kD, surrounded by a 5-prime untranslated region of 61 nucleotides and a 3-prime untranslated region of 277 nucleotides. The protein shows 84% identity with the translation product of the rat beta-ureidopropionase cDNA.

Expression of the human cDNA in Escherichia coli and eukaryotic COS-7 cells revealed a very high beta-ureidopropionase enzymatic activity, thus confirming the identity of the cDNA. Human EST libraries from brain, liver, kidney, and heart contained partial beta-ureidopropionase cDNAs, suggesting expression in these tissues, as seen in the rat.