hydrolysis of glucose-6-phosphate
DESCRIPTION
Hydrolysis of Glucose-6-Phosphate. ∆Gº = –3.3 kcal/mol. = –13.8 kJ/mol. High ∆Gº Hydrolysis Compounds. ∆Gº = –14.8 kcal/mol = –61.9 kJ/mol. High ∆Gº Hydrolysis Compounds. ∆Gº = –11.8 kcal/mol = –49.3 kJ/mol. High ∆Gº Hydrolysis Compounds. ∆Gº = –10.3 kcal/mol = –43 kJ/mol. - PowerPoint PPT PresentationTRANSCRIPT
Hydrolysis of Glucose-6-Phosphate
∆Gº = –3.3 kcal/mol= –13.8 kJ/mol
O
CH2OP
O
O
HO
+ H2O O
CH2HO+ OHP
O
O
HOO
CH2OP
O
O
HO
+ H2O O
CH2HO+ OHP
O
O
HO
Ionization,resonance
Productstabilization
High ∆Gº Hydrolysis Compounds
∆Gº = –14.8 kcal/mol = –61.9 kJ/mol
OC
O
C
CH2
O P
O
O
O
Pi
H2OO
CO
C
CH2
OH
OC
O
C
CH3
O
Phospho-enolpyruvate
(PEP)
enol-ketoisomerization
High ∆Gº Hydrolysis Compounds
∆Gº = –11.8 kcal/mol = –49.3 kJ/mol
CO O
CH
PO O
O
HO
CH2 O P
O
O
O
1,3-Bisphosphoglyceric Acid(1,3-diPGA)
COO
CH OH
CH2OP
O
O
OH2O
Pi H
Resonancestabilized
High ∆Gº Hydrolysis Compounds
∆Gº = –10.3 kcal/mol = –43 kJ/mol
OC
O
CH2
N CH3
C NH
NH
P OO
O
H2O
OC
O
CH2
N CH3
C NH
NH2
+ Pi
PhosphocreatineResonance
possible
Phosphate Anhydrides (Pyrophosphates)
∆Gº = –7.3 kcal/mol = –30.5 kJ/mol
O P
O
O
O P
O
O
O P
O
O
O CH2
OAdenine
OHHORepulsion
H2O
ADP + Pi
Adenosine triphosphate(ATP)
Thiol Esters
∆Gº = –7.5 kcal/mol = –31.4 kJ/mol
CoA S C
O
CH3
CoASH
+
+
H3C CO
O
H
H2O
Thiol Esters
R1
CS
R2
O
R1
CS
R2
O
R1
CO
R2
O
R1
CO
R2
O
Thiol ester less resonance-stabilized
“High-Energy” Compounds• Large ∆Gº hydrolysis
– Bond strain (electrostatic repulsion) in reactant• ATP
– Products stabilized by ionization• Acyl-P
– Products stabilized by isomerization• PEP
– Products stabilized by resonance• Creatine-P
“High-Energy” Compounds
• “High-energy” compound is one with a ∆Gº below –6 kcal/mol (–25 kJ/mol)
High-Energy Compounds
Group Transfer Potential
Lecture 25
Chemical Sense in Metabolism