RESUMO
An abnormal ninhydrin positive compound was observed in the urine of two unrelated patients with neurological abnormalities. The compound was isolated by cation exchange followed by preparative paper chromatography and finally purified via cation exchange column chromatography. Its identification as O-phosphohydroxylysine resulted from FAB mass spectrometry and NMR spectroscopy. Chemical synthesis confirmed the structure. It was tentatively postulated that these patients had a defect of the metabolism of hydroxylysine, viz., a deficiency of the enzyme O-phosphohydroxylysine phospholyase.
Assuntos
Hidroxilisina/análogos & derivados , Erros Inatos do Metabolismo/urina , Adolescente , Criança , Cromatografia em Camada Fina , Eletroforese , Feminino , Humanos , Hidrólise , Hidroxilisina/metabolismo , Hidroxilisina/urina , Espectroscopia de Ressonância Magnética/métodos , MasculinoRESUMO
Two brothers, aged 7 and 5 years, who excreted large amounts of the leucine metabolites 3-methylglutaconic acid, 3-methylglutaric acid, and 3-hydroxyisovaleric acid, are described. The excretion of these metabolites could be enhanced by increasing the leucine intake. Restriction of the protein intake resulted in a marked reduction of the metabolite excretion. However, the excretion of the ultimate leucine metabolite, 3-hydroxy-3-methylglutaric acid, remained unchanged at a low level. The only clinical abnormality was speech retardation. A (partial) deficiency of 3-methylglutaconyl coenzyme A hydratase is proposed to be the most likely underlying defect.
