RESUMO

The molecular nature of the glycine cleavage system was investigated in eight patients with typical (neonatal) and two patients with atypical (late onset) nonketotic hyperglycinemia (NKH). The overall activity of the glycine cleavage system was found to be decreased in all of the liver and brain tissue studied, but it was undetectable or extremely low in typical NKH, whereas there was some residual activity in atypical NKH. Six patients with typical NKH had a specific defect in the P protein, and one a defect in the T protein; the activity of the T protein was defective in one patient with atypical NKH.

Assuntos

Aminoácido Oxirredutases/metabolismo , Proteínas de Transporte/metabolismo , Glicina/sangue , Hidroximetil e Formil Transferases , Erros Inatos do Metabolismo/sangue , Complexos Multienzimáticos/metabolismo , Transferases/metabolismo , Aminometiltransferase , Encéfalo/enzimologia , Glicina/líquido cefalorraquidiano , Humanos , Lactente , Recém-Nascido , Fígado/enzimologia , Erros Inatos do Metabolismo/líquido cefalorraquidiano , Fenótipo , Transtornos Psicomotores/sangue