What is catabolism vs anabolism?
Catabolism breaks down big molecules for energy
Anabolism is the synthesis of bigger molecules from small molecules
What two molecules are convergence points for sugar fatty acid, and amino acid metabolism?
pyruvate, Acetyl-CoA
What is the key chemical process that is happening to sugar-derived metabolites during glycolysis and the citric acid cycle?
stepwise oxidation of molecules
What molecules are being reduced as sugar-derived metabolites are modified?
NAD+ gets turned into NADH and FADH2
In what form is carbon released when it is fully oxidized
CO2
What process is yielding ATP during glycolysis and the citric acid cycle?
substrate level phosphorylation
What is oxidized in during oxidative phosphorylation?
NADH, FADH2 gets turned into NAD+
What is being reduced during oxidative phosphorylation?
metabolites, it’s a anabolic reaction
What is produced as a product of the transport of electrons from NADH and FADH2 to O2?
proton gradient
What is the proton gradient coupled to?
ATP synthase for ATP synthesis
What are four generalizations of catabolic pathways?
oxidative process of fuel molecules
generate ATP
generate reduced electron carriers
converse on intermediates (pyruvate, Acetyl-CoA)
What are two generalizations of anabolic pathways?
reductive biosynthesis (and using NADPH)
use ATP
What does a very negative delta G step mean in a reaction?
irreversible, determines the direction of the entire pathway
What are control points?
steps that have a very negative delta G, irreversible
What is allosteric activation?
effectors that bind to a site away from the active site, stabilize the R state and increase affinity
What is allosteric inhibition?
inhibitors that bind to a site away from the active site, stabilize the T state, decrease affinity
What is product inhibiton?
immediate product of enzyme competes with substrate from binding to active site
What is covalent modification?
adding a covalent bond to change enzyme activity, such as phosphorylation
What is regulation of enzyme availability?
Transcription controlled
Sequestration- inhibitory protein binds to enzyme, making it unavailable
What is a substrate cycle?
sets of opposing cycles of catabolic/anabolic pathways
Glycolysis and gluconeogenesis are opposing pathways. What reactions do they share?
the ones that are near equilibrium (delta G near 0)
What type of bonds hold up ATP/ADP/AMP?
phosphoanhydride bonds
What are the three reasons why transferring a phosphoryl group from ATP has a highly negative delta G?
resonance stabilization is greater in products
electrostatic repulsion is reduced after hydrolysis
hydrolysis products are better solvated
What are the three ways that ATP can be used as energy currency?
transfer phosphate groups to metabolites to power endergonic reactions
transfer phosphoryl groups to proteins to make conformational changes
regenerate nucleotide triphosphate
