gluconeogenesis Flashcards
(25 cards)
what is the breaking up meaning of gluco-neo-genesis
synthesis of new glucose
what is glucogeogenesis
metabolic pathway that generates glucose from non carbohydrate carbon substrates like lactate, pyruvate
why do we use gluconeogenesis
brain and central nervous system use glucose as their sole energy
what is the reversal of glycolysis
gluconeogenesis
what steps do glycolysis and glucogenesis have in common
hexokinase–> G6P
pfk 1 –> Fructose 1,6-bisphosphate
PK—> pyru. carbox. and pep carboxylase
what is similar to hexokinase in gluconeogenesis
glucokinase, isozyme of glycolysis in liver
to bypass pyruvate kinase what two enzymes are involved
pyruvate carboxylase and PEPCK
what does pyruvate carboxylase do
catalyzes the atp and biotin dependent conversionof pyruv. oxaloacetate in the mitochondrial matrix
what does PEPCK
uses gtp to convert oxaloacetate to phosphoenolpyruvate by phosphorylation
pyruvate carb. uses what cofactor
biotin and it involves CO2
what is the net atp. gtp, atp, NADH in gluconeo
2 atp
2Gtp = atp equivalent
2 ATP
2 nAdh
where does gluconeogenesis happen
90% in the liver
what bypasses glucokinase
glucose 6 phosphate
why is the liver important
huge reservoir or buffer for glucose
glucokinase never achieves equilibirrum
where do the reactions happen
in the cytosol except pyruvate carboxylase and some pep carb. happen in the mitochondria matrix
what else is considred a part of gluconeo
malate DH
what is reciprocal regulation
must turn one on and the other off
what is an example of reciprocal regulation
fructose 6 phosphate and fructose 1,6 bisphosphate
what two enzymes take place at the same time
phosphofructokinase and fructose 1,6 bisphosphatase
what catalyzes a prochiral differentiation
LDH
even though glycolysis is anaerobic what needs to be regenerated to sustain glycolysis
NAd+
what is lactobacillus
lactose into lactic acid in yogurt
what is transferred to the liver where it
is turned back to glucose (
muscle lactate
where can glucogenesis start
lactate
