The conversion of glucose to pyruvate occurs in 2 phases , what are they ? What is the net amount ATP per glucose molecule ?
Energy investment phase : phosphorylated forms of intermediates are synthesized at the expense of ATP.
Energy generation phase : a net of 2 molecules of ATP are formed by substrate-level phosphorylation per glucose molecule metabolized.
The irreversible phosphorylation of glucose by what enzymes allows for glucose to be trapped as the sugar as cytosolic glucose-6-phosphate (G-6-P)inside a cell ?
Hexokinase - muscles other cells
Gluckokinase -Liver and Pancrease
Hexokinase is inhibited by what molecule ?
G-6-Phosphate
The isomerization of G-6-P to
fructose-6-phosphate is catalyzed by ?
phosphoglucose isomerase
The irreversible phosphorylation of F-6-P to
Fructose-1,6-bisphosphate is catalyzed by ?
Why is This reaction is the most important control point and rate limiting and
committed step of glycolysis ? (regulatory point #2)
phosphofructokinase-1 (PFK-1)
It is irreversible
Fructose-1,6-bisphosphate is cleaved to dihydroxyacetone phosphate and
glyceraldehyde-3-phosphate by what enzyme ?
aldolase
What catalyzes the interconversion of DHAP and G-3-P so that it can be used in the next ?step. DHAP must be isomerized to G-3-P for furthermetabolism by the glycolytic pathway
Triose phosphate isomerase
Yields two G-3-P's
G-3-P is oxidized to
1,3-bisphosphoglycerate by what enzyme ?During this step the NADH formed by this reaction must be reoxidized back to NAD+ for glycolysis to continue.
Glyceraldehyde 3-phosphate dehydrogenase
What are the 2 major mechanisms for oxidizing NADH ?
1)The NADH linked conversion of pyruvate to lactate (anaerobic)
2) Oxidation of NADH via the respiratory chain (aerobic)
1,3-bisphosphoglycerate (1,3-BPG) is converted to 3-phosphoglycertae by the enzyme ?
In this reaction thehigh energy phosphate
group of 1,3-BPG is used to synthesize ATP from ADP
phosphoglycerate kinase
3-phosphoglycerate is converted to 2-phosphoglycertae by what enzyme ?
phosphoglycerate mutase
2-phosphoglycerate is dehydrated to phosphoenolpyruvate (PEP) by what enzyme ?
What can inhibit this enzyme ?
enolase
Fluoride
Phosphoenolpyruvate (PEP) is converted
to pyruvate by what enzyme ?
This is the third irreversible reaction of glycolysis (regulatory point #3)