lOMoARcPSD|26676891
BMSC 230 Chapter Summaries
Metabolism (University of Saskatchewan)
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BMSC 230 Chapter Summaries
Chapter 15
15.1
- catabolism: getting energy from fuel
- anabolism: rxns that use energy for biosynthesis
- spontaneous rxns have a negative free energy
- thermodynamically unfavorable rxns can be driven by a thermodynamically favorable one
(hydrolysis of ATP)
15.2
- energy derived from catabolism takes form of ATP
- ATP hydrolysis is exergonic and the energy released can be used for cellular processes
- ATP hydrolysis shifts the equilibrium of a coupled rxn by 10 8
- ATP contains 2 phosphoanhydride linkages
15.3
- ATP formation is coupled to the oxidation of carbon fuels
- Electrons are removed from C and added to O2 in a series of REDOX rxns
- As electrons flow down an gradient they release energy
- Energy from C oxidation can be trapped as high-phosphoryl-transfer-potential compounds
- Energy from above can be used to synthesise ATP
15.4
- ATP, NADPH, acetyl CoA -> activated carriers, transfer activated groups
- NADPH carries 2 e- and provides energy in biosynthesis of cell components
- activated carries are derived from vitamins
15.5
- amounts of critical enzymes are controlled by regulation of synthesis and degradation
- catalytic activities of enzymes are regulated by allosteric interactions and covalent modification
- movements of substrates into cellular components is controlled
- energy charge is dependent on amounts of ATP, AMP, ADP
- high energy charge inhibits ATP generation but activates ATP utilization
Chapter 16
16.1
- glycolysis converts glucose to pyruvate
- takes place in cytoplasm
- first stage: glucose converted to fructose 1,6-biphosphate by phosphorylation, isomerization,
and phosphorylation
- 2 m’cles of ATP are consumed for each of the 3 rxns (6ATP)
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- fructose 1,6-biphosphate is then is cleaved by aldolase into dihydroxyacetone phosphate and
glyceraldehyde 3-phosphate (reversible)
- glyceraldehyde 3-phosphate is oxidized and phosphorylated to form 1,3-biphosphoglycerate
- 1,3-biphosphoglycerate transfers a phosphoryl group from ADP to for ATP and 3-
phosphoglycerate
- phosphoryl shift and dehydration of 3-phosphoglycerate forms phosphoenolpyruvate
- another m’cle of ATP is formed when phosphoenolpyruvate is converted to pyruvate
- net gain of 2 ATP m’cles in the formation of 2 pyruvate m’cles from 1 m’cle of glucose
16.2
- NAD+ is electron acceptor in oxidation of glyceraldehyde 3-phosphate
- NAD+ must be regenerated for glycolysis to continue
- NADH formed in glycolysis transfers e- to O2 through ETC to regenerate NAD+ (aerobic)
- NAD+ is regenerated from reduction of pyruvate to lactose (anaerobic)
- NAD+ is regenerated by reduction of pyruvate to ethanol (other)
16.3
- fructose and galactose are also used for fuel
- must be converted to intermediates before they can be used in the glycolytic pathway
- fructose is phosphorylated into fructose 6-phosphate
- fructose 1-phosphate is formed in the liver and then cleaved to dihydroxyacetone phosphate and
glyceraldehyde
- glyceraldehyde is phosphorylated to form glyceraldehyde 3-phosphate
- galactose is converted to glucose 1-phosphate in a 4-step process that includes UDP-glucose
- glucose 1-phosphate is converted into glucose 6-phosphate by phosphoglucomutase
16.4
- glycolytic pathway degrades glucose for ATP and provides building blocks for the synthesis of
cellular components
- conversion of glucose into pyruvate is regulated based off cellular needs
- rxns of glycolysis are reversible EXCEPT for rxns catalyzed by hexokinase, phosphofructokinase,
pyruvate kinase
- phosphofructokinase is inhibited by high levels of ATP and citrate, activated by AMP and fructose
2,6-biphosphate
- in the liver, this signals that there is a high level of glucose
- phosphofructokinase is activated when building blocks or energy is needed
- hexokinase is inhibited by glucose 6-phosphate, which accumulates when phosphofructokinase
is inactive
- ATP and alanine allosterically inhibit pyruvate kinase, fructose 1,6-phosphate activates
- pyruvate kinase is most active when energy levels are low and glycolytic intermediates
accumulate
16.5
- insulin stimulates uptake of glucose by adipose tissue and muscle
BMSC 230 Chapter Summaries
Metabolism (University of Saskatchewan)
, lOMoARcPSD|26676891
BMSC 230 Chapter Summaries
Chapter 15
15.1
- catabolism: getting energy from fuel
- anabolism: rxns that use energy for biosynthesis
- spontaneous rxns have a negative free energy
- thermodynamically unfavorable rxns can be driven by a thermodynamically favorable one
(hydrolysis of ATP)
15.2
- energy derived from catabolism takes form of ATP
- ATP hydrolysis is exergonic and the energy released can be used for cellular processes
- ATP hydrolysis shifts the equilibrium of a coupled rxn by 10 8
- ATP contains 2 phosphoanhydride linkages
15.3
- ATP formation is coupled to the oxidation of carbon fuels
- Electrons are removed from C and added to O2 in a series of REDOX rxns
- As electrons flow down an gradient they release energy
- Energy from C oxidation can be trapped as high-phosphoryl-transfer-potential compounds
- Energy from above can be used to synthesise ATP
15.4
- ATP, NADPH, acetyl CoA -> activated carriers, transfer activated groups
- NADPH carries 2 e- and provides energy in biosynthesis of cell components
- activated carries are derived from vitamins
15.5
- amounts of critical enzymes are controlled by regulation of synthesis and degradation
- catalytic activities of enzymes are regulated by allosteric interactions and covalent modification
- movements of substrates into cellular components is controlled
- energy charge is dependent on amounts of ATP, AMP, ADP
- high energy charge inhibits ATP generation but activates ATP utilization
Chapter 16
16.1
- glycolysis converts glucose to pyruvate
- takes place in cytoplasm
- first stage: glucose converted to fructose 1,6-biphosphate by phosphorylation, isomerization,
and phosphorylation
- 2 m’cles of ATP are consumed for each of the 3 rxns (6ATP)
, lOMoARcPSD|26676891
- fructose 1,6-biphosphate is then is cleaved by aldolase into dihydroxyacetone phosphate and
glyceraldehyde 3-phosphate (reversible)
- glyceraldehyde 3-phosphate is oxidized and phosphorylated to form 1,3-biphosphoglycerate
- 1,3-biphosphoglycerate transfers a phosphoryl group from ADP to for ATP and 3-
phosphoglycerate
- phosphoryl shift and dehydration of 3-phosphoglycerate forms phosphoenolpyruvate
- another m’cle of ATP is formed when phosphoenolpyruvate is converted to pyruvate
- net gain of 2 ATP m’cles in the formation of 2 pyruvate m’cles from 1 m’cle of glucose
16.2
- NAD+ is electron acceptor in oxidation of glyceraldehyde 3-phosphate
- NAD+ must be regenerated for glycolysis to continue
- NADH formed in glycolysis transfers e- to O2 through ETC to regenerate NAD+ (aerobic)
- NAD+ is regenerated from reduction of pyruvate to lactose (anaerobic)
- NAD+ is regenerated by reduction of pyruvate to ethanol (other)
16.3
- fructose and galactose are also used for fuel
- must be converted to intermediates before they can be used in the glycolytic pathway
- fructose is phosphorylated into fructose 6-phosphate
- fructose 1-phosphate is formed in the liver and then cleaved to dihydroxyacetone phosphate and
glyceraldehyde
- glyceraldehyde is phosphorylated to form glyceraldehyde 3-phosphate
- galactose is converted to glucose 1-phosphate in a 4-step process that includes UDP-glucose
- glucose 1-phosphate is converted into glucose 6-phosphate by phosphoglucomutase
16.4
- glycolytic pathway degrades glucose for ATP and provides building blocks for the synthesis of
cellular components
- conversion of glucose into pyruvate is regulated based off cellular needs
- rxns of glycolysis are reversible EXCEPT for rxns catalyzed by hexokinase, phosphofructokinase,
pyruvate kinase
- phosphofructokinase is inhibited by high levels of ATP and citrate, activated by AMP and fructose
2,6-biphosphate
- in the liver, this signals that there is a high level of glucose
- phosphofructokinase is activated when building blocks or energy is needed
- hexokinase is inhibited by glucose 6-phosphate, which accumulates when phosphofructokinase
is inactive
- ATP and alanine allosterically inhibit pyruvate kinase, fructose 1,6-phosphate activates
- pyruvate kinase is most active when energy levels are low and glycolytic intermediates
accumulate
16.5
- insulin stimulates uptake of glucose by adipose tissue and muscle
