Download - 15 Glycolysis Glycogenesis
GLUCONEOGENESIS & GLYCOLYSISHigh Blood GlucoseINSULINREACTANTS PRODUCTS
Glucose Pi
GLUCOSE3.1.3.9
LIVER
GLUCOSE2.7.1.1
REACTANTS PRODUCTS
GlucoseATP
H2O
Endoplasmic Reticulum
Glucose-6-P5.3.1.9
Glucose-6-P5.3.1.9
ADP
GLUCAGON
Low Blood Glucose
Fructose-6-PPi H2O 3.1.3.11
Fructose-6-P2.7.1.11
ATP ADP
YC GL
ER
OL
3P-Glyce rol
Fructose-1,6-bis-P4.1.2.13
Di-OH-acetone-P 5.3.1.1 (Glycerone-P)2Pi 2 NAD+
3-P-Glyceraldehyde1.2.1.12
2NADH+2H+2 ADP 2 ATP
2x 1,3-bis-P-Glycerate2.7.2.3
2x 3-P-Glycerate5.4.2.1
2x 2-P-Glycerate2H2O 2CO2 2 GDP 2 GTP 4.1.1.32 4.2.1.11
G L U C O N E O G E N E S I S
Fructose-1,6-bis-P4.1.2.13
Di-OH-acetone-P G (Glycerone-P) L Y C 3-P-Glyceraldehyde O 2 NAD+ 1.2.1.12 2 Pi L 2NADH+2H+ Y 2x 1,3-bis-P-Glycerate S 2 ADP 2.7.2.3 I 2 ATP S 2x 3-P-Glycerate5.4.2.1
SCLE MU
GLUCOSE
2x 2-P-Glycerate4.2.1.11 2H2O 2 ADP 2 ATP
2x P-enolpyruvate 2x Oxaloacetate1.1.1.37
2x P-Enolpyruvate2.7.1.40
PYRUVATENADH+H+1.1.1.27
2NADH+2H+2 NAD+
Glutamate 2.6.1.21
2x PYRUVATE2 PEP
2NADH+2H+
2-Oxoglutarate
1.1.1.27
2x Malate 2x Malate2NAD+
2 Aspartate
NAD+
2x LACTATEMitochondrial Outer Membrane Mitochondrial Inner Membrane Mitochondrial Matrix
LACTATE
2 Aspartate2.6.1.21 Glutamate
2 PEP 2x PYRUVATEACETYL-CoAOxaloacetate Malate Succinyl-CoA Citrate4.1.1.32
2-Oxoglutarate
Amino acid 2 ADP 2 ATP 2H2O 2 Pi
2x Oxaloacetate
2x Oxaloacetate
**
6.4.1.1
**
** 6.4.1.1 **2x PYRUVATE
2CO2 2 PYRUVATE
2x PYRUVATE 2x Succinyl-CoA 2x PYRUVATEGlutamate 2.6.1.21
ATP
2x Succinyl-CoA5.4.99.2
2x PYRUVATE
2-Oxoglutarate
2NADH+2H+ 2NAD+
2 (S)-Methylmalonyl-CoA5.1.99.11.1.1.27
GL
UC
2 (R)-Methylmalonyl-CoA VALINE ISOLEUCINE METHIONINE
AG ON
ATP+CO2 6.4.1.3 ADP+Pi
2x LACTATE CO
2x ALANINE
2x PROPIONYL-CoA
RI C Y CLE
Low Blood Glucose
GLYCOLYSISGLUCONEOGENESIS
Glucose + 2ADP + 2Pi + 2NAD
++
Low Blood Glucose
2NADH+2H+
1.1.1.37
2 CO2 2GDP
Cytoplasmic Membrane
2GTP
2 Pyruvate + 2ATP + 2NADH + 2H
Cytosol
+
+ 2H2O+
Comparison of the two equations shows that: OXIDATION of 1 GLUCOSE to 2 PYRUVATE produces 2ATP whereas REDUCTION of 2 PYRUVATE to 1 GLUCOSE requires 4ATP + 2GTP To make GLUCONEOGENESIS thermodynamically possible requires the hydrolysis of the equivalent of 6ATPGluconeogenesis needs NADH for the reduction of 1,3-bis-P-glycerate to triose-P. For most precursors this is formed in the mitochondria and transported across the mitochondrial membrane via malate. Lactate is unique in that lactate dehydrogenase only occurs in the cytosol so that NADH is directly available in the cytosol for gluconeogenesis. However, the resulting pyruvate can only be converted into oxaloacetate within mitochondria since this is the only site of pyruvate carboxylase. The oxaloacetate so formed can then be transported into the cytosol by direct carboxylation to PEP or by transamination to aspartate in the mitochondria and then reverse transamination to oxaloacetate in the cytosolENZYMES Pyruvate kinase 5.1.99.1 Phosphoglycerate kinase 5.3.1.1 Glucose-6-phosphatase 5.4.2.1 Fructose-bisphosphatase 5.4.99.2 Phosphoenolpyruvate carboxykinase 6.2.1.17 Fructose-bisphosphatealdolase 6.4.1.1 Phosphopyruvate hydratase 6.4.1.3
2 Pyruvate + 4ATP + 2GTP + 2NADH + 2H + 6H2O
Glucose + 4ADP + 2GDP + 6Pi + 2NAD
1.1.1.27 Lactate dehydrogenase (only in cytosol) 1.1.1.37 Malate dehydrogenase 1.2.1.12 Glyceraldehyde-3-P dehydrogenase 2.7.1.1 Hexokinase 2.7.1.30 Glycerolkinase 2.7.1.11 6-Phosphofructokinase Liver Hexokinase is Hexokinase D (or IV) (Often called Glucokinase)
2.7.1.40 2.7.2.3 3.1.3.9 3.1.3.11 4.1.1.32 4.1.2.13 4.2.1.11
**
Methylmalonyl-CoA epimerase Triosephosphate isomerase Phosphoglycerate mutase Methylmalonyl-Co mutase Propionate-CoA ligase Pyruvate carboxylase (only in matrix) Propionyl-CoA carboxylase
Designed by Donald Nicholson
c 2002 IUBMB