A deficiency of the enzyme NADP dependent xylitol dehydrogenase (L-xylulose reductase) has previously been found to be the cause of chronic essential pentosuria. (wits.ac.za)
Essential pentosuria is a recessively inherited condition which is marked by the continual excretion of relatively large amounts of the enzymes substrate, L-xylulose. (wits.ac.za)
A L-xylulose reductase assay suitable for the identification of carriers of essential pentosuria was developed and tested on members of a South African Lebanese family in which the inheritance of pentosuria had previously been suggested to be dominant. (wits.ac.za)
While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. (diabeteshealthmatters.com)
Dicarbonyl2
Dicarbonyl/L-xylulose reductase, also known as carbonyl reductase II, is an enzyme that in human is encoded by the DCXR gene located on chromosome 17. (wikipedia.org)
This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. (diabeteshealthmatters.com)
Xylitol6
In enzymology, an L-xylulose reductase (EC 1.1.1.10) is an enzyme that catalyzes the chemical reaction xylitol + NADP+ ⇌ {\displaystyle \rightleftharpoons } L-xylulose + NADPH + H+ Thus, the two substrates of this enzyme are xylitol and NADP+, whereas its 3 products are L-xylulose, NADPH, and H+. (wikipedia.org)
Xylulose Xylitol (Note conversion of ketone to alcohol) This enzyme belongs to the superfamily of short-chain oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. (wikipedia.org)
The systematic name of this enzyme class is xylitol:NADP+ 2-oxidoreductase (L-xylulose-forming). (wikipedia.org)
The minor isozyme is e1ectrophoretica 1 1 y distinct from the major isozyme, has markedly higher Michael is constants for the substrates L-xylulose and xylitol and shows a lower pH optimum when catalysing the oxidation of xylitol. (wits.ac.za)
One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. (diabeteshealthmatters.com)
Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. (diabeteshealthmatters.com)
Deficiency1
A deficiency is responsible for pentosuria. (wikipedia.org)
Excessive1
The insufficiency of L-xylulose reductase activity causes an inborn error of metabolism disease characterized by excessive urinary excretion of L-xylulose. (wikipedia.org)
Gene1
The pentosuria allele could then be used as a gene marker in linkage studies aimed at mapping the L-xylulose reductase locus. (wits.ac.za)
Cell1
No evidence of tight linkage was found between the pentosuria allele's locus and those coding for various red cell antigens, red cell enzymes and serum proteins. (wits.ac.za)
Condition1
This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. (diabeteshealthmatters.com)