Function
GLUD1 catalyses the oxidative deamination of Glu to 2-oxoglutarate and free NH4+ using either NAD+ or NADP+ as a co-factor. The reaction occurs with the transfer of a hydride ion from Glu's Cα to NAD(P)+, thereby forming 2-iminoglutarate, which is hydrolyzed to 2-oxoglutarate and NH4+. The reaction's equilibrium under standard circumstances greatly favors Glu formation over NH4+ (Go' ~ 30 kJ.mol-1) formation. For this reason, it was thought that the enzyme played an important role in ammonia detoxification, because since high are toxic, this equilibrium position would be physiologically important; it would help to maintain low . However, in individuals with a certain form of hyperammonemia resulting from a form of hyperinsulinism, the enzyme's activity is increased due to decreased GTP sensitivy, a negative regulator. These individual's blood ammonia levels are raised significantly, which would not be expected if the enzyme did indeed operate at equilibrium.
Read more about this topic: Glutamate Dehydrogenase 1
Famous quotes containing the word function:
“As a medium of exchange,... worrying regulates intimacy, and it is often an appropriate response to ordinary demands that begin to feel excessive. But from a modernized Freudian view, worrying—as a reflex response to demand—never puts the self or the objects of its interest into question, and that is precisely its function in psychic life. It domesticates self-doubt.”
—Adam Phillips, British child psychoanalyst. “Worrying and Its Discontents,” in On Kissing, Tickling, and Being Bored, p. 58, Harvard University Press (1993)
“Think of the tools in a tool-box: there is a hammer, pliers, a saw, a screwdriver, a rule, a glue-pot, nails and screws.—The function of words are as diverse as the functions of these objects.”
—Ludwig Wittgenstein (1889–1951)
“The press and politicians. A delicate relationship. Too close, and danger ensues. Too far apart and democracy itself cannot function without the essential exchange of information. Creative leaks, a discreet lunch, interchange in the Lobby, the art of the unattributable telephone call, late at night.”
—Howard Brenton (b. 1942)