What are the 3 irriversible steps in glycolysis?
- Phosphofructose kinase 1 (PFK-1)
- Pyruvate Kinase
What is the Enzyme that is rate determining in Gycolysis?
What is the committing step in glycolysis?
- Formation of 1,6-bisphosphate bc it is committed to Glycolysis
- The previous steps could have gone to other pathways like HMP shunt or glycogen synthesis
Phosphorylation of glucose to G-6-Phosphate is done by what enzymes in the muscle, brain and liver?
- Muscle, brain, Liver--Hexokinase
- Beta-cells, liver--glucokinase
Whats the negative feedback inhibition for Hexokinase?
- Glucokinase--no inhibitor
What are the only ketogenic A.A..capable of forming ketone bodies to be used as energy by the brain?
Lysine and Leucine
High levels of Fructose 1,6 - bisphosphate stimulate what enzyme in the Glycolytic Pathway?
What inhibits pyruvate kinase enzyme glycolysis?
phosphorylation by protein kinase A which is activated by cAMP which is in turn activated by glucagon
What inhibits Hexokinase?
Glucose 6 phosphate
What inhibits Glucokinase
Fructose 6 phosphate
Whats an allosteric activator of PFK-1?
Fructose 2,6 Bisphosphate
PFK-2 kinase activity is active when it is phosphorylated or dephosphorylated?
PFK-2 phosphatase activity is active when phospho or dephosphorylated?
Phosphorylation of glycolytic enzymes leads to their activation or inactivation?
Whats the consequence of converting 1,3 bisphosphoglycerate to 2,3 bisphosphoglycerate?
Loss of an ATP
Arsenic blocks what glycolytic enzyme?
Glyceraldehyde-3 phosphate dehydrogenase
Flouride blocks what glycolytic enzyme?
Whats the function of enolase?
converts phosphoenolpyruvate to pyruvate
What enzyme is similar to alpha ketoglutarate dehydrogenase?
Pyruvate dehydrogenase Complex
What are the cofactors needed for alpha ketoglutarate dehydrogenase?
- 2. lipoic acid
- 5. FAD
- 6. coA
ionic calcium in TCA cycle stimulates what enzymes?
Isocitrate dehydrogenase and apha ketoglutarate dehydrogenase
Whats the product of hydrogenating alpha ketoglutarate?
Arsenic blocks what in glycolysis?
- Glyceraldehyde 3 phosphate dehydrogenase
- In PDC binds Lipoic Acid
Flouroacetate (RAT poison) blocks what?
Aconitase which converts citrate to isocitrate
Arsenic blocks what enzymes?
- In glycolysis--glyceraldehyde 3 phosphate dehydrogenase
- In TCA-- alpha KG dehydrogenase and succinic dehydrogenase
- In PDC--lipoic acid