Transcript watcut.uwaterloo.ca

Glucose is an indispensable metabolite
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The brain requires at least ~50% of its calories in the form of
glucose
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Red blood cells exclusively subsist on glucose
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Glucose is a precursor of other sugars needed in the
biosynthesis of nucleotides, glycoproteins, and glycolipids
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Glucose is needed to replenish NADPH, which supplies
reducing power for biosynthesis and detoxification
© Michael Palmer 2014
The pyruvate carboxylase reaction
© Michael Palmer 2014
The active site of E. coli biotin carboxylase
© Michael Palmer 2014
Activation of bicarbonate and carboxylation of
biotin
© Michael Palmer 2014
The carboxylation of pyruvate
© Michael Palmer 2014
The phosphoenolpyruvate carboxykinase reaction
© Michael Palmer 2014
Fructose-1,6-bisphosphatase and glucose-6phosphatase
© Michael Palmer 2014
Energy balance of gluconeogenesis
© Michael Palmer 2014
Mitochondrial substrate transport in
gluconeogenesis
© Michael Palmer 2014
Ethanol degradation inhibits gluconeogenesis
© Michael Palmer 2014
Simultaneous activity of glycolysis and
gluconeogenesis creates futile cycles
© Michael Palmer 2014
Glucose phosphorylation cycling involves two
separate compartments
© Michael Palmer 2014
Allosteric regulation limits fructose-6-phosphate
phosphorylationcycling
© Michael Palmer 2014
Hormonal control of phosphofructokinase
andfructose-1,6-bisphosphatase
© Michael Palmer 2014
The secondary messengers cAMP and fructose-2,6bisphosphate
© Michael Palmer 2014
Regulation of pyruvate kinase
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allosteric inhibition by ATP
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allosteric activation by alanine and fructose-1,6-bisphosphate
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inhibition by PKA-mediated phosphorylation