• Corpus ID: 12348750

On the mechanism of L-alloisoleucine formation: studies on a healthy subject and in fibroblasts from normals and patients with maple syrup urine disease.

  title={On the mechanism of L-alloisoleucine formation: studies on a healthy subject and in fibroblasts from normals and patients with maple syrup urine disease.},
  author={Peter Schadewaldt and H. -W. Hammen and C. Dalle-Feste and Udo Wendel},
  journal={Journal of inherited metabolic disease},
  volume={13 2},
L-Alloisoleucine formation from L-isoleucine was studied in vitro and in vivo. When a healthy subject was loaded with L-isoleucine, plasma levels of L-isoleucine and 3-methyl-2-oxopentanoate (KMV), as well as L-alloisoleucine, increased. Peak values were reached successively and were in the order L-isoleucine much greater than KMV much greater than L-alloisoleucine. Metabolic clearance of L-isoleucine and KMV was rapid; clearance of L-alloisoleucine was considerably delayed. When human skin… 
Significance of L-alloisoleucine in plasma for diagnosis of maple syrup urine disease.
The present findings indicate that plasma L-alloisoleucine above the cutoff value of 5 micromol/L is the most specific and most sensitive diagnostic marker for all forms of MSUD.
Branched-chain L-amino acid metabolism in classical maple syrup urine disease after orthotopic liver transplantation
Most likely, the enhanced substrate supply from extrahepatic sources led to an elevation of the plasma concentrations and thus induced a compensatory enhancement of the metabolic flux through the branched-chain 2-oxo acid dehydrogenase complex in the intact liver tissue.
Human branched-chain L-amino acid aminotransferase: Activity and subcellular localization in cultured skin fibroblasts
The data suggest that, in human fibroblasts, isoenzyme type I resides within the mitochondrial space and possible implications for the metabolism of branched-chain compounds are discussed.
Renal clearance of branched-chain L-amino and 2-oxo acids in maple syrup urine disease
The results show that the renal excretion of free BCAA as well as of the acylated derivatives is negligible and the renalexcretion of BCOA, however, to some extent counteracts increases in BCAA concentrations and thus contributes to the lowering of total BCAA pools in MSUD.
Maple syrup urine disease: Interrelations between branched-chain amino-, oxo- and hydroxyacids; implications for treatment; associations with CNS dysmyelination
A relaxed treatment protocol for patients with maple syrup urine disease may benefit them in quality of life, but it apparently exacts a cost in metabolic control and CNS pathology.
A Rapid and Sensitive UPLC-MS/MS-Method for the Separation and Quantification of Branched-Chain Amino Acids from Dried Blood Samples of Patients with Maple Syrup Urine Disease (MSUD)
Newborn screening for MSUD is a special challenge since patients with MSUD can metabolically decompensate rapidly without adequate treatment within the first two weeks of life. However, the screening
Chiral compounds in metabolism: a look in the molecular mirror
This article provides a background to the field of enantiomers and their analysis as demonstrated by examples of inborn errors of metabolism and hints at the possible discovery of as yet unidentified metabolic pathways.