Liver biopsy samples from the patients with hyperphenylalaninemia have an average of 5 percent of the normal hydroxylase activity. The parents of the patients have between 7.3 percent (excluding the value for one parent) and 10 percent of the normal hepatic hydroxylase activity. An explanation for these findings involves negative interallelic complementation, which involves protein-protein interaction between subunits in a multimeric enzyme. In support of this model is the evidence that rat liver phenylalanine hydroxylase is a multimeric protein composed of two electrophoretically distinguishable subunits.

DOI:
Version: za2963e q8zab q8zb7 q8zcd q8zd5 q8zee q8zff q8zgb