Detection of transaldolase deficiency by quantification of novel seven-carbon chain carbohydrate biomarkers in urine.

Transaldolase deficiency, a recently discovered disorder of carbohydrate metabolism with multisystem involvement, has been diagnosed in 6 patients. Affected patients have abnormal concentrations of polyols in body fluids and in all patients we have previously found increased amounts of a seven-carbon chain carbohydrate which we suspected of being sedoheptulose. We report development of a liquid chromatography-tandem mass spectrometry method for quantitation of the seven-carbon carbohydrates sedoheptulose and mannoheptulose in urine. Additionally, other seven-carbon chain carbohydrates were characterized in urine, including sedoheptitol, perseitol and sedoheptulose 7-phosphate. Transaldolase-deficient patients had significantly increased urinary sedoheptulose and sedoheptulose 7-phosphate, associated with subtle elevations of mannoheptulose, sedoheptitol and perseitol. Our findings reveal novel urinary biomarkers for identification of transaldolase deficiency.

Study of transaldolase deficiency in urine samples by capillary LC-MS/MS.

Transaldolase (TAL) is a key enzyme of the pentose phosphate pathway (PPP). TAL deficiency is a newly recognized cause of liver cirrhosis. We have developed an ion-pair LC separation combined with negative ion electrospray MS/MS detection method to assess PPP metabolites in urine samples from TAL-deficient mice. Sedoheptulose 7-phosphate (S7P), C5-polyols D-arabitol and D-ribitol, and 6-phosphogluconate (6PG) levels were markedly increased in urine of TAL-deficient mice with respect to those of wild-type and heterozygote littermates. The detection limits of S7P, D-arabitol, and 6PG were 0.15 +/- 0.015 pmol, 3.5 +/- 0.41 pmol, and 0.61 +/- 0.055 pmol, respectively. The limit of quantitation was 0.4 +/- 0.024 nmol/ml for S7P, 1.6 +/- 0.11 nmol/ml for 6PG and 10 +/- 0.7 nmol/ml for D-arabitol. Additional metabolites, hexose 6-phosphates (m/z 259), D-ribose 5-phosphate and D-xylulose 5-phosphate (m/z 229), D-fructose 1,6-diphosphate (m/z 339), C6-polyols (m/z 181) and GSSG (m/z 611), that have been positively identified in mouse urine, showed similar levels in control and TAL-deficient mice.

Urinary sugar phosphates and related organic acids in fructose-1,6-diphosphatase deficiency.

Two sisters with fructose-1,6-diphosphatase deficiency are reported. They presented with ketonuria, elevated plasma transaminase activity and severe metabolic acidosis during hypoglycaemic crises, which resembled Reye syndrome. Intravenous fructose tolerance tests provoked severe hypoglycaemia and metabolic acidosis. Fructose-1,6-diphosphatase activities in both peripheral leukocytes and cultured lymphocytes were below the limit of detection. Urinary organic acid analysis during crises revealed markedly increased excretion of lactate, ketone bodies, glycerol and glycerol-3-phosphate. We newly identified other glycolytic intermediates, glyceraldehyde, 3-phosphoglycerate and fructose-1,6-diphosphate, in the urine during hypoglycaemic attacks or after fructose tolerance tests. Identification of such compounds may be useful in the early diagnosis of this disease.

Determination of the structure of a fucose-containing trisaccharide monophosphate isolated from human pregnancy urine.

A new acidic oligosaccharide, isolated from the urine of a pregnant woman by gel filtration and ion-exchange chromatography, was shown on the basis of sugar analysis, methylation analysis, exo-glycosidase digestion, e.i.-m.s., f.a.b.-m.s., and n.m.r. spectroscopy to have the following structure: (Formula: see text).