Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 1.1.1.22 extracted from

  • Kadirvelraj, R.; Sennett, N.C.; Custer, G.S.; Phillips, R.S.; Wood, Z.A.
    Hysteresis and negative cooperativity in human UDP-glucose dehydrogenase (2013), Biochemistry, 52, 1456-1465.
    View publication on PubMed

Protein Variants

Protein Variants Comment Organism
K94E substitution prevents hexamer formation. Mutant does not display hysteresis Homo sapiens

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
0.016
-
UDP-alpha-D-glucose wild-type, pH 7.5, 25°C Homo sapiens
0.269
-
UDP-alpha-D-glucose mutant K94E, pH 7.5, 25°C Homo sapiens
0.942
-
NAD+ wild-type, pH 7.5, 25°C, Hill coefficient 0.74 Homo sapiens
2.92
-
NAD+ mutant K94E, pH 7.5, 25°C Homo sapiens

Organism

Organism UniProt Comment Textmining
Homo sapiens O60701
-
-

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
additional information enzyme displays hysteresis, observed as a lag in progress curves, and is sensitive to product inhibition during the lag. The inhibition results in a systematic decrease in steady-state velocity and makes the lag appear to have a second-order dependence on enzyme concentration.The lag is in fact due to a substrate and cofactor-induced isomerization of the enzyme. The cofactor binds to the enzyme:substrate complex with negative cooperativity, suggesting that the isomerization may be related to the formation of an asymmetric enzyme complex Homo sapiens ?
-
?
UDP-alpha-D-glucose + 2 NAD+ + H2O
-
Homo sapiens UDP-alpha-D-glucuronate + 2 NADH + 2 H+
-
?

Turnover Number [1/s]

Turnover Number Minimum [1/s] Turnover Number Maximum [1/s] Substrate Comment Organism Structure
0.012
-
UDP-alpha-D-glucose mutant K94E, pH 7.5, 25°C Homo sapiens
0.055
-
NAD+ mutant K94E, pH 7.5, 25°C Homo sapiens
1.4
-
UDP-alpha-D-glucose wild-type, pH 7.5, 25°C Homo sapiens
1.8
-
NAD+ wild-type, pH 7.5, 25°C, Hill coefficient 0.74 Homo sapiens

General Information

General Information Comment Organism
physiological function enzyme displays hysteresis, observed as a lag in progress curves, and is sensitive to product inhibition during the lag. The inhibition results in a systematic decrease in steady-state velocity and makes the lag appear to have a second-order dependence on enzyme concentration.The lag is in fact due to a substrate and cofactor-induced isomerization of the enzyme. The cofactor binds to the enzyme:substrate complex with negative cooperativity, suggesting that the isomerization may be related to the formation of an asymmetric enzyme complex. The hysteresis may be the consequence of a functional adaptation, by slowing the response of the enzyme to sudden increases in the flux of substrate, the other biochemical pathways that use this important metabolite will have a competitive edge Homo sapiens