title: Interrelation between the metabolism of L-isoleucine and L-allo-isoleucine in patients with maple syrup urine disease.
abstract: The nonprotein amino acid L-allo-isoleucine is formed endogenously in maple syrup urine disease patients from (R)-3-methyl-2-oxo-pentanoic acid. During strict metabolic balance, the plasma L-allo-isoleucine/L-isoleucine ratio correlates inversely with the residual activity of the branched-chain 2-oxoacid dehydrogenase in fibroblasts and thus constitutes a relevant in vivo parameter of the severity of the metabolic defect in MSUD patients.
authors.affiliation: Kinderklinik, Universität Düsseldorf, Federal Republic of Germany.
authors.forename: U
authors.initials: U
authors.lastname: Wendel
authors.forename: U
authors.initials: U
authors.lastname: Langenbeck
authors.forename: J W
authors.initials: JW
authors.lastname: Seakins
mesh_terms: D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide); D055598:Chemical Phenomena; D002621:Chemistry; D002675:Child, Preschool; D005260:Female; D005347:Fibroblasts / Q000201:enzymology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007532:Isoleucine / Q000097:blood*; D007536:Isomerism; D007658:Ketone Oxidoreductases / Q000378:metabolism; D007700:Kinetics; D008297:Male; D008375:Maple Syrup Urine Disease / Q000175:diagnosis / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000378:metabolism
chemical_list: D009097:Multienzyme Complexes; D007532:Isoleucine; D007658:Ketone Oxidoreductases; D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)