Regulation Flashcards
Hexokinase
Glucokinase
GLYCOLYSIS STEP 1
Glucose + ATP —> Glucose-6-phosphate + ADP
Hexokinase: feedback inhibited by G-6-P
Glucokinase: inducible by insulin
PFK-1
GLYCOLYSIS- STEP 3 RATE LIMITING
Fructose-6-phosphate + ATP —> fructose-1,6-bisphosphate + ADP
(+) AMP, fructose-2,6-bisphosphate
(-) ATP
PFK-2
Fructose-6-phosphate —> fructose-2,6-bisphosphate
(+) fed and dephos
(-) fasted and phos
Pyruvate kinase
STEP 10 GLYCOLYSIS
Phosphoenolpyruvate + ADP + Pi —> pyruvate + ATP
(+) fructose-1,6-bisphosphate
(-) ATP
(+) fed and dephos
(-) fasted and phos
PDH complex
Pyruvate + NAD+ + CoA —> acetyl CoA + NADH + CO2 + H+
(+) ADP, NAD+, pyruvate
(-) ATP, acetyl CoA, NADH
(+) fed and dephos
(-) fasted and phos
Isocitrate dehydrogenase
TCA CYCLE RATE LIMITING
Isocitrate + NAD+ + H+ —> alpha-ketoglutarate + NADH + CO2
(+) ADP, NAD+
(-) ATP, NADH
Alpha-ketoglutarate dehydrogenase
TCA Cycle
Alphaketoglutarate + NAD+ + CoA —> succinyl CoA + NADH + CO2
Feedback inhibited by succinyl CoA
(-) ATP, NADH
Glycogen synthase
UDP-glucose + glycogen —> glycogen + UDP
(+) fed and dephos
(-) fasted and phos
Glycogen phosphorylase
Glycogen —> glucose
Muscle (+) AMP
Liver (-) glucose
(+) fasted and phos
(-) fed and dephos
Acetyl CoA carboxylase
Fatty Acid Synthesis RATE LIMITING
Acetyl CoA + ATP + HCO3- —> malonyl CoA + ADP + Pi + H+
(+) citrate
(-) palmitoyl CoA
(+) fed and dephos
(-) fasted and phos
HMG-CoA reductase
Cholesterol Synthesis
HMG-CoA + 2 NADPH + 2 H+ —> Mevalonate + NADP+ + CoA
(+) fed and dephos
(-) fasted and phos
Pyruvate carboxylase
Fatty acid synthesis and gluconeogenesis
(+) acetyl CoA, ATP
(-) ADP
PEPCK
Gluconeogenesis
OAA + GTP —> PEP + CO2 + GDP
(-)ADP
Glucose-6-phosphatase
Gluconeogenesis
G-6-P + H2O —> glucose + Pi
Substrate level
