Energy, Catalysis and Biosynthesis
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Transcript of Energy, Catalysis and Biosynthesis
Energy, Catalysis and BiosynthesisMetabolism
*catabolism
*anabolism
Complexity of metabolism
*potential energy
Conservation of EnergyEnergy is defined as the capacity to perform work.Kinetic energy is the energy of motion.Potential energy is stored energy.
Free energy, stability, and changeFree energyChange in free energy = DG
Gravitational Motion
Diffusion Chemical Reaction
Equilibrium*chemical equilibriumDG = 0, no net change in the system
Chemical reactions with free energy changes:*energetically favorable *energetically unfavorable
Free energy, stability, and change
Metabolic Disequilibrium
*Multistep open hydroelectric system
Enzymes–Metabolism is the total of all chemical reactions in an organism.–Most metabolic reactions require the assistance of enzymes, proteins that speed up chemical reactions.
Induced Fit
Enzymes
Enzymes are catalytic proteins Enzymes lower the barrier of EA
Enzymes
(a) Without enzyme (b) With enzyme
Reactant Reactant
Products Products
Activationenergy barrier Activation
energy barrierreduced byenzyme
Enzyme
Ener
gy le
vel
Ener
gy le
vel
Activation Energy–Activation energy•Activates the reactants •Triggers a chemical reaction–Enzymes lower the activation energy for chemical reactions.
Enzymes
Substrate
Substrate
Substrate
Active site
Active site
Active site
Inhibitor
Inhibitor
Enzymes Physical and chemical properties affect enzyme activity:
*inhibitors
*cofactor*coenzyme
*activators
ATP and Cellular Work
Main types of (cellular) work: mechanicaltransportchemical
The Structure of ATP
Triphosphate Diphosphate
Adenosine Adenosine
Energy
ATP ADP
P P P P P P
Phosphate(transferred to
another molecule)
– ATP (adenosine triphosphate)• Consists of adenosine plus a tail of three
phosphate groups • Is broken down to ADP and a phosphate group,
releasing energy
The Structure of ATP
ATP
ATP
ATP
ADP
ADP
ADP
P
P
P
ADP P
P P
P
PX X YY
(a) Motor protein performing mechanical work
(b) Transport protein performing transport work
(c) Chemical reactants performing chemical work
Solute
Solute transported
Protein moved
Product madeReactants
Transportprotein
Motor protein
ATP and Cellular Work
ATP and Cellular Work