Literature summary for 2.7.7.12 extracted from

Lai, K.; Langley, S.D.; Dembure, P.P.; Hjelm, L.N.; Elsas, L.J.2nd.
Duarte allele impairs biostability of galactose-1-phosphate uridyltransferase in human lymphoblasts (1998), Hum. Mutat., 11, 28-38.

Search for more literature for 2.7.7.12

Cloned(Commentary)

Cloned (Comment)	Organism
expression of N314D mutants in human lymphoblasts	Homo sapiens

Protein Variants

Protein Variants	Comment	Organism
E203K	native heterozygous mutant, reduced activity by about 50% in erythrocytes	Homo sapiens
N314D	native missense mutant Duarte D, homozygous, characteristic isoform, partial impairment of enzyme activity in human erythrocytes, fibroblasts, and transformed lymphoblasts, reduced Vmax, increased thermal lability	Homo sapiens
N314D/E203K	homozygous N314D mutant with introduced cis mutation E203K does no longer show the reduced, but the full activity and increased thermolablity of mutant without E203K	Homo sapiens

Inhibitors

Inhibitors	Comment	Organism	Structure
cycloheximide	i.e. 3-[2-(3,5-dimethyl-2-oxocyclohexyl)-2-hydroxyethyl]glutarimide; inhibition of de novo enzyme synthesis; mutant N314D is more sensitive than the wild-type	Homo sapiens

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
0.13	-	UDP-glucose	wild-type from lymphoblasts, 37°C	Homo sapiens
0.14	-	UDP-glucose	N314D homozygous mutant from lymphoblasts, 37°C	Homo sapiens
0.2	-	UDP-glucose	wild-type from erythrocytes, 37°C	Homo sapiens

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
86000	-	nondenaturing PAGE	Homo sapiens

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
UDP-glucose + alpha-D-galactose 1-phosphate	Homo sapiens	essential enzyme in galactose metabolism, deficiency causes genetic disorder galactosemia, e.g. mutant Duarte variant	alpha-D-glucose 1-phosphate + UDP-galactose	-	r

Organism

Organism	UniProt	Comment	Textmining
Homo sapiens	-	missense mutant N314D, Duarte allele	-

Purification (Commentary)

Purification (Comment)	Organism
70600fold from erythrocytes	Homo sapiens

Reaction

Reaction	Comment	Organism	Reaction ID
UDP-alpha-D-glucose + alpha-D-galactose 1-phosphate = alpha-D-glucose 1-phosphate + UDP-alpha-D-galactose	reaction mechanism of Duarte mutant N314D	Homo sapiens	a

Source Tissue

Source Tissue	Comment	Organism	Textmining
erythrocyte	-	Homo sapiens	-
fibroblast	-	Homo sapiens	-
lymphoblast	-	Homo sapiens	-

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg]	Specific Activity Maximum [µmol/min/mg]	Comment	Organism
additional information	-	activity in different genotypes	Homo sapiens
16.8	-	purified enzyme	Homo sapiens

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
UDP-glucose + alpha-D-galactose 1-phosphate	-	Homo sapiens	alpha-D-glucose 1-phosphate + UDP-galactose	-	r
UDP-glucose + alpha-D-galactose 1-phosphate	essential enzyme in galactose metabolism, deficiency causes genetic disorder galactosemia, e.g. mutant Duarte variant	Homo sapiens	alpha-D-glucose 1-phosphate + UDP-galactose	-	r

Synonyms

Synonyms	Comment	Organism
GALT	-	Homo sapiens

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
37	-	assay at	Homo sapiens

Temperature Stability [°C]

Temperature Stability Minimum [°C]	Temperature Stability Maximum [°C]	Comment	Organism
additional information	-	increased thermal lability of the mutant N314D compared to the wild-type	Homo sapiens
50	-	15 min, 30% loss of activity for the wild-type enzyme, over 55% loss of activity for the homozygous N314D mutant	Homo sapiens

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Release 2023.1 (January 2023)