Identification of the D-enantiomer of 2-hydroxyglutaric acid in glutaric aciduria type II.
We determined the optical isomer of the 2-hydroxyglutaric acid (2HG) that was elevated in the urine of five Japanese children with a mild form of glutaric aciduria type II (GA2), caused by a deficiency of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). The D- and L-enantiomers of 2HG were separated by capillary gas chromatography with a combination of (S)-(+)-2-octanol derivatization and chromatography on a DB-1 column. The isomer that was elevated in GA2 patients was predominantly the D-enantiomer, an observation that may serve as an additional marker for the biochemical diagnosis of GA2. D-2HG dehydrogenation, but not L-2HG dehydrogenation is apparently blocked in GA2. A specific D-2HG dehydrogenase or D-2HG-CoA dehydrogenase may be metabolically linked to ETF and ETF-QO in the mitochondria.
Watanabe
H
H
Department of Pediatrics, Gifu University School of Medicine, Japan.
Yamaguchi
S
S
Saiki
K
K
Shimizu
N
N
Fukao
T
T
Kondo
N
N
Orii
T
T
D015415:Biomarkers; D002648:Child; D008401:Gas Chromatography-Mass Spectrometry; D005977:Glutarates / Q000652:urine*; D006801:Humans; D015151:Immunoblotting; D007564:Japan; D000608:Renal Aminoacidurias / Q000175:diagnosis / Q000652:urine*; D013237:Stereoisomerism
D015415:Biomarkers; D005977:Glutarates; C019417:alpha-hydroxyglutarate