BCM252: STUDY UNIT 1
Chapter 14: Summary
- Glycolysis, a process by which cells can extract a limited amount of energy from glucose
- Endogenous polysaccharides and dietary disaccharides and polysaccharides are degraded by
phosphorolysis and hydrolysis, respectively
- generated, hexoses are phosphorylated and funneled into glycolysis
- Fermentation, a process by which cells can continue using glycolysis to extract energy in anaerobic
conditions
Chapter 14.1 Glycolysis
Central importance of glucose
1. Glucose is an excellent fuel.
- yields a good amount of energy upon oxidation (loss of protons/H)
o 2840 kJ/mol glucose
- can be efficiently stored in the polymeric form
- Many organisms and tissues can meet their energy needs on glucose only
2. Glucose is a versatile biochemical precursor.
- Many organisms can use glucose to generate:
o all the amino acids
o membrane lipids
o nucleotides in DNA and RNA
o cofactors needed for metabolism
Four Major Pathways of Glucose Utilization
1. Storage
- can be stored in the polymeric form (starch, glycogen)
- used for later energy needs
2. Energy production
- generates energy via oxidation of glucose
- short-term energy needs
3. Production of NADPH and pentoses
- generates NADPH for use in relieving oxidative stress (injury by radicals of reactive oxygen species) and synthesizing fatty
acids
- generates pentose phosphates for use in DNA/RNA biosynthesis
4. Structural carbohydrate production
- used for generation of alternate carbohydrates used in cell walls of bacteria, fungi, and plants
,Glycolysis: Importance
- Sequence of 10 enzyme-catalyzed reactions by which glucose (6C molecule) is
converted into pyruvate (3C molecule).
o Pyruvate can be further aerobically oxidized.
o Pyruvate can be used as a precursor in biosynthesis.
- Some of the free energy is captured by the synthesis of ATP and NADH.
- Research of glycolysis played a large role in the development of modern biochemistry.
o understanding the role of coenzymes
o discovery of the pivotal role of ATP
o development of methods for enzyme purification
o inspiration for the next generations of biochemists
,Glycolysis: Overview
-
-
-
-
o
o
-
Glycolysis: The Preparatory Phase
, Glycolysis: The Payoff Phase
Glycolysis: The Role of Enzymes
Harnessing energy from glucose via glycolysis is
facilitated by enzymes
Cofactors:
- Some enzymes require an additional
chemical component called a cofactor – either
one or more inorganic ions
- Examples are Copper, Iron, Potassium,
Magnesium, Manganese, Nickel and Zinc
- Cofactor: an inorganic ion or a coenzyme
required for enzyme activity.
Coenzymes:
- Some enzymes also contain a complex organic or
metalloorganic molecule called a coenzyme
- Coenzymes act as transient carriers of specific functional
groups
- Examples are Biocytin, Coenzyme A, Flavin adenine
dinucleotide (FAD), Lipoate, Nicotinamide adenine
dinucleotide (NAD), Pyridoxal phosphate, Tetrahydrofolate,
Thiamine pyrophosphate (TPP)
- Coenzyme: an organic cofactor required for the action of
certain enzymes; often has a vitamin component.
Chapter 14: Summary
- Glycolysis, a process by which cells can extract a limited amount of energy from glucose
- Endogenous polysaccharides and dietary disaccharides and polysaccharides are degraded by
phosphorolysis and hydrolysis, respectively
- generated, hexoses are phosphorylated and funneled into glycolysis
- Fermentation, a process by which cells can continue using glycolysis to extract energy in anaerobic
conditions
Chapter 14.1 Glycolysis
Central importance of glucose
1. Glucose is an excellent fuel.
- yields a good amount of energy upon oxidation (loss of protons/H)
o 2840 kJ/mol glucose
- can be efficiently stored in the polymeric form
- Many organisms and tissues can meet their energy needs on glucose only
2. Glucose is a versatile biochemical precursor.
- Many organisms can use glucose to generate:
o all the amino acids
o membrane lipids
o nucleotides in DNA and RNA
o cofactors needed for metabolism
Four Major Pathways of Glucose Utilization
1. Storage
- can be stored in the polymeric form (starch, glycogen)
- used for later energy needs
2. Energy production
- generates energy via oxidation of glucose
- short-term energy needs
3. Production of NADPH and pentoses
- generates NADPH for use in relieving oxidative stress (injury by radicals of reactive oxygen species) and synthesizing fatty
acids
- generates pentose phosphates for use in DNA/RNA biosynthesis
4. Structural carbohydrate production
- used for generation of alternate carbohydrates used in cell walls of bacteria, fungi, and plants
,Glycolysis: Importance
- Sequence of 10 enzyme-catalyzed reactions by which glucose (6C molecule) is
converted into pyruvate (3C molecule).
o Pyruvate can be further aerobically oxidized.
o Pyruvate can be used as a precursor in biosynthesis.
- Some of the free energy is captured by the synthesis of ATP and NADH.
- Research of glycolysis played a large role in the development of modern biochemistry.
o understanding the role of coenzymes
o discovery of the pivotal role of ATP
o development of methods for enzyme purification
o inspiration for the next generations of biochemists
,Glycolysis: Overview
-
-
-
-
o
o
-
Glycolysis: The Preparatory Phase
, Glycolysis: The Payoff Phase
Glycolysis: The Role of Enzymes
Harnessing energy from glucose via glycolysis is
facilitated by enzymes
Cofactors:
- Some enzymes require an additional
chemical component called a cofactor – either
one or more inorganic ions
- Examples are Copper, Iron, Potassium,
Magnesium, Manganese, Nickel and Zinc
- Cofactor: an inorganic ion or a coenzyme
required for enzyme activity.
Coenzymes:
- Some enzymes also contain a complex organic or
metalloorganic molecule called a coenzyme
- Coenzymes act as transient carriers of specific functional
groups
- Examples are Biocytin, Coenzyme A, Flavin adenine
dinucleotide (FAD), Lipoate, Nicotinamide adenine
dinucleotide (NAD), Pyridoxal phosphate, Tetrahydrofolate,
Thiamine pyrophosphate (TPP)
- Coenzyme: an organic cofactor required for the action of
certain enzymes; often has a vitamin component.
