Van Coster RN, Gerlo EA, Giardina TG, Engelke UF, Smet JE, De Praeter CM, Meersschaut VA, De Meirleir LJ, Seneca SH, Devreese B, Leroy JG, Herga S, Perrier JP, Wevers RA, Lissens W. Aminoacylase I deficiency: a novel inborn error of metabolism.
Biochem Biophys Res Commun 2005;
338:1322-6. [PMID:
16274666 DOI:
10.1016/j.bbrc.2005.10.126]
[Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Accepted: 10/24/2005] [Indexed: 11/27/2022]
Abstract
This is the first report of a patient with aminoacylase I deficiency. High amounts of N-acetylated amino acids were detected by gas chromatography-mass spectrometry in the urine, including the derivatives of serine, glutamic acid, alanine, methionine, glycine, and smaller amounts of threonine, leucine, valine, and isoleucine. NMR spectroscopy confirmed these findings and, in addition, showed the presence of N-acetylglutamine and N-acetylasparagine. In EBV transformed lymphoblasts, aminoacylase I activity was deficient. Loss of activity was due to decreased amounts of aminoacylase I protein. The amount of mRNA for the aminoacylase I was decreased. DNA sequencing of the encoding ACY1 gene showed a homozygous c.1057 C>T transition, predicting a p.Arg353Cys substitution. Both parents were heterozygous for the mutation. The mutation was also detected in 5/161 controls. To exclude the possibility of a genetic polymorphism, protein expression studies were performed showing that the mutant protein had lost catalytic activity.
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