Alanine-glyoxylate transaminase (AGXT) catalyzes the irreversible reaction of glyoxylate and alanine to form glycine and pyruvate (Danpure and Jennings 1988). The active form of the enzyme is a homodimer (Zhang et al. 2003) with one molecule of pyridoxal phosphate bound to each subunit (Coulter-Mackie et al. 2005). Mutations in this enzyme are associated with primary hyperoxaluria type I. Mutant alleles encode both catalytically inactive proteins and active ones that are mis-localized to mitochondria (Purdue et al. 1990; Takada et al. 1990).