Biomaterial Database

Purification and properties of UDP-glucose (UDP-galactose) pyrophosphorylase from Bifidobacterium bifidum. 1979

L Lee, and A Kimura, and T Tochikura

An enzyme having both UDP-glucose (UDP-Glc) and UDP-galactose (UDP-Gal) pyrophosphorylase activities was purified to homogeneity from Bifidobacterium bifidum. The molecular weight of the enzyme was about 200,000 and it appeared to be composed of four identical subunits. The purified enzyme showed almost the same reactivity towards UDP-Glc and UDP-Gal, and showed about 10% of this activity towards UDP-xylose at 8 mM. The enzyme required magnesium ions for maximum activity. The apparent equilibrium constants were about 2.5 for UDP-Glc pyrophosphorolysis and 1.1 for UDP-Gal pyrophosphorolysis. The enzyme activities were inhibited by various nucleotides (product or substrate analogs). Some sugar phosphates, such as fructose 6-P, erythrose 4-P, and 3-phosphoglycerate, stimulated the activities. These properties are discussed in relation to the significance of the enzyme in galactose metabolism of B. bifidum.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009713	Nucleotidyltransferases	A class of enzymes that transfers nucleotidyl residues. EC 2.7.7.	Nucleotidyltransferase
D005694	UTP-Hexose-1-Phosphate Uridylyltransferase	An enzyme that catalyzes the synthesis of UDPgalactose from UTP and galactose-1-phosphate. It is present in low levels in fetal and infant liver, but increases with age, thereby enabling galactosemic infants who survive to develop the capacity to metabolize galactose. EC 2.7.7.10.	Galactosephosphate Uridylyltransferase,UDP Galactose Pyrophosphorylase,Galactose-1-Phosphate Uridyltransferase,Galactose 1 Phosphate Uridyltransferase,Galactose Pyrophosphorylase, UDP,Pyrophosphorylase, UDP Galactose,UTP Hexose 1 Phosphate Uridylyltransferase,Uridyltransferase, Galactose-1-Phosphate,Uridylyltransferase, Galactosephosphate,Uridylyltransferase, UTP-Hexose-1-Phosphate
D005957	UTP-Glucose-1-Phosphate Uridylyltransferase	An enzyme that catalyzes the formation of UDPglucose from UTP plus glucose 1-phosphate. EC 2.7.7.9.	Glucosephosphate Uridylyltransferase,UDP Glucose Pyrophosphorylase,UDPG Pyrophosphorylase,Pyrophosphorylase, UDP Glucose,Pyrophosphorylase, UDPG,UTP Glucose 1 Phosphate Uridylyltransferase,Uridylyltransferase, Glucosephosphate,Uridylyltransferase, UTP-Glucose-1-Phosphate
D000191	Actinomycetaceae	A family of bacteria including numerous parasitic and pathogenic forms.
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities