Galactose 1-phosphate uridylyltransferase

T14. Severity of Clinical Symptoms Due to Enzyme Deficiency The clinical symptoms of two forms of galactosemia—deficiency of galactokinase or of UDP-glucose galactose 1-phosphate uridylyltransferase— show radically different severity. Although both types produce gastric discomfort after milk ingestion, deficiency of the transferase also leads to liver, kidney, spleen, and brain dysfunction and eventual death. What products accumulate in the blood and tissues with each type of enzyme deficiency Estimate the relative toxicities of these products from the above information. 

Answer In galactokinase deficiency, galactose accumulates in UDP-glucose galactose 1-phosphate uridylyltransferase deficiency, galactose 1-phosphate accumulates (see Fig. 14-12). The latter metabolite is clearly more toxic. 

Case B (c) Galactose 1-phosphate uridylyltransferase is an enzyme involved in conversion of galactose to glucose, which then can enter glycolysis. Absence of this enzyme leads to accumulation of galactose in the blood and excretion in the urine. A patient with this deficiency should be on a low-lactose diet (treatment 3). 

Erin Galway has galactosemia, which is caused by a deficiency of j galactose 1-phosphate uridylyltransferase it is one of the most common genetic diseases. Galactosemia is an autosomal recessive disorder of galactose metabolism that occurs in about 1 in 60,000 newborns. Approximately two... 

BL1643 was annotated to be a galactose 1-phosphate uridylyltransferase (EC 2.7.7.10) (GalT2), meaning the enzyme transfers the UMP (uridine monophosphate) unit of UTP (uridine triphosphate) to GallP. Although the LnpC protein did not have this activity, it showed UDP-glucose-hexose 1-phosphate uridylyltransferase... 

Figure 8.9. Output of a PASTA search, (a) Hit list from a PASTA search with human histidine triad (HIT) protein (SWISS-PROT P49789) as the query against the swissprot database. The search was performed using ktup = 1. (b) Optimal local alignment of the query to one of the database entries (marked by arrow in hit list) containing the sequence of rat galactose-1-phosphate uridylyltransferase (GalT). Although the sequence similarity is weak, these proteins have been shown to share structural similarity.

McCorvie TJ, et al. Misfolding of galactose 1-phosphate uridylyltransferase can result in type I galactosemia. Biochim Biophys Acta. 2013 1832(8) 1279-93. 

Negative selection It allows snrvival of only transformed cells, such as galT (galactose-1-phosphate uridylyltransferase), badh (betaine aldehyde dehydrogenase), DOGRl (2-deoxyglucose-6-phosphate phosphatase), and codA (cytosine deaminase). 

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