GAPDH mechanism Flashcards
1
Q
what is the first step of the GAPDH mechanism (after the enzyme substrate complex has already formed)?
A
Cys thiol acts as a nucleophile and attacks the aldehyde to form a thio-hemiacetal His as GB
2
Q
what is the second step of the GAPDH mechanism?
A
thiohemiacetal undergoes oxidation to an acyl thioester by direct hydride transfer to NAD+
3
Q
what is the third step of the GAPDH mechanism?
A
NAD+ replaces NADH
4
Q
what is the fourth step of the GAPDH mechanism?
A
inorganic P attacks the thioester to form 1,3-BPG and free cys (regenerates enzyme) His as GA
5
Q
what happens to the energy released by C oxidation?
A
energy released by C oxidation is converted into high-phosphoryl transfer potential
