Term
|
Definition
Acetyl-CoA + OAA → Citrate + CoASH .
Rapid and Exergonic. Break thioester bond.
Inhibited by NADH and succinyl CoA
Important in bacteria not man |
|
|
Term
|
Definition
Citrate -> Isocitrate (dehydration)
Poisioned by Zn++, fluro-acetate
Zn inhibits enzymes requuiring bivalent metal cofactors |
|
|
Term
|
Definition
Isocitrate + NAD+ → NADH + H+ + α-ketoglutarate + CO2
Oxidation and Decarboxylation
Major regulater:
Inhibited: NADH, ATP
Activated: ADP, Ca++
Phosphorlation at serine prevents binding of isocitrate |
|
|
Term
| α-ketoglutarate dehydrogenase |
|
Definition
α-ketoglutarate + CoASH + NAD+ succinyl CoA + NADH + H+ + CO2
Oxidation and decarboxylation
Similar to Pyr DEH(requires CoASH and other coenzymes) However not regulated by phosphorylation
Inhibited: ATP, GTP, NADH, Succinyl-CoA
Activated: Ca+
Arenite poisoning |
|
|
Term
|
Definition
AsO3-- binds reactive –SH groups(Cysteine)
α-ketoglutarate Deh, Pyruvate Deh and Succinate Deh |
|
|
Term
|
Definition
Succinyl-CoA + GDP + Pi Succinate + CoASH + GTP
Breaks high-energy thioester bond.
Recycles CoASH in matrix(used in α-ketoglutarate deh step) |
|
|
Term
|
Definition
Succinate + FAD ←→ Fumarate + FADH2
Enzyme is only membrane bound in TCA cycle
Inhibited by Arsenite/aresenate(AsO32-) |
|
|
Term
|
Definition
Malate + NAD+ ←→ Oxaloacetate + NADH + H+
Oxidation to produce NADH vs oxidative decarboxylations of two other NADH produced |
|
|
Term
| Major regulatory factor of Pyr Deh and TCA cycle |
|
Definition
NAD+ / NADH ratio.
Tied to oxidative phosphorylation. Replenishes NAD+ and FAD |
|
|
Term
Destination of TCA intermediates
Citrate
a-ketoglutarate
Succinyl-CoA
OAA |
|
Definition
Citrate → Fatty Acids, Steroids
α-ketoglutarate → Glutamate → Amino Acids, purines Succcinyl-CoA → Heme, chlorophyll
OAA → Aspartate → Amino acids, purines, pyrimidine’s
Enzymes must be inhibited |
|
|
Term
|
Definition
DHAP + NADH → Glycerol-3-P + NAD+. Glyercerol-3-P can cross mitochondria membrane. In inner membrane Glycerol-3-P + FAD → FADH2 + DHAP DHAP returns to cytosol.
Glycerophosphate deh is enzyme
e- shuttled to FADH2 |
|
|
Term
|
Definition
OAA reduced to Malate. NADH → NAD+ Malate moves to matrix
Malate Oxidized to OAA in mitochondria. NADH is now in matrix.
OAA transaminated to create α-ketoglutarate and aspartate; moves to cytosol
in cytosol. α-ketoglutarate + aspartate → OAA and glutamate
Shuttling of e- to make NADH |
|
|
