LSM2101 Part I Lecture 7 Gluconeogenesis

• Synthesis of glucose from:
• lactate
• glycerol
• glucogenic amino acids, e.g. alanine
• odd fatty acid chains -> propionyl-CoA
• Reverse of Glycolysis, but:
• Hexokinase -> Glucose-6-phosphatase
• Pyruvate Carboxylase: pyruvate -> oxaloacetate
• PEPCK: oxaloacetate -> PEP
• other enzymes are the same
• Location: 90% liver, 10% kidney
• Pyr Carboxylase: in mitochondria
• PEPCK: in mitochondria or cytosol
• Transfer from mitochondria -> cytosol:
• Malate Route (generate NADH)
• Aspartate Route
• PEP channel
• Regulations
• Pyruvate Carboxylase: (+) acetyl-CoA
• PFK: (+) AMP, F2,6BP (-)citrate,ATP vs. FBPase: (-) AMP, F2,6BP
• PFK2: (+)AMP, Pi, F6P (-)citrate, ATP vs. FBPase2: (-) F6P (+)G3P 
• Diseases
• Deficient in Pyruvate Carboxylase: lactic acidosis, hypoglycemia
• Deficient in FBP: no gluconeogenesis
• Anaerobic glycolysis = production of lactate
• in erythrocytes, tissues of eyes, skeletal muscle (short of ATP)
• Recycle of lactate: Cori cycle, in liver
• Adipose Tissue
• store fatty acids as triacylglyceride
• broken to: glycerol + FAs, transported to liver
• Glycerol -> Glucose
• FA (odd) -> propionyl-CoA -> succinyl-CoA -> glucose
• Glucose-Alanine Cycle
• Pyruvate -> Alanine (transamination), in muscles
• Alanine -> Pyruvate, in liver