Human liver L-alanine-glyoxylate aminotransferase: characteristics and activity in controls and hyperoxaluria type I patients using a simple spectrophotometric method.

We have studied the characteristics of human liver alanine-glyoxylate aminotransferase, which is deficient in hyperoxaluria type I, an inherited disorder of glyoxylate metabolism. The enzyme was optimally active at pH 8.0 showing apparent Km values for L-alanine and glyoxylate of 8.3 and 1.3 mmol/l, respectively. Activity was found to proceed linearly for up to 4 h. Measurements under these optimal conditions enabled the biochemical diagnosis of hyperoxaluria type I to be made via enzyme activity measurements in percutaneous needle biopsy specimens of liver tissue.