Download 20141031093018

AP Biology
Living Metabolism
Part 1
Catabolism
(Hydrolysis Reaction)
Free energy
Reactants
Amount of
energy
released
(G < 0)
Energy
Products
Progress of the reaction
Exergonic reaction: energy released
Anabolism
(Dehydration
Synthesis)
Free energy
Products
Energy
Reactants
Progress of the reaction
Endergonic reaction: energy required
Amount of
energy
required
(G > 0)
Energy Coupling
Two processes united by Energy
Kinetic Energy vs. Potential
Energy
Potential Energy vs. Kinetic
Energy
Potential Energy vs. Kinetic
Energy
Thermodynamics
LE 8-3
Heat
Chemical
energy
First law of thermodynamics
CO2
H2O
Second law of thermodynamics
Δ G = ΔH – TΔ S
G- Gibbs “free” energy
H – Enthalpy (Total usable energy in the
system)
 T – Temperature in Kelvin (273 + C⁰)
 S- Entropy (Disorder created by
something being broken down)
 Δ – Change in a variable over time



Gibbs “Free” Energy
Unstable (Capable of
work)
vs.
Stable (no work)
G < 0
A closed hydroelectric system
G = 0
LE 8-6a
Free energy
Reactants
Amount of
energy
released
(G < 0)
Energy
Products
Progress of the reaction
Exergonic reaction: energy released
LE 8-6b
Free energy
Products
Energy
Reactants
Progress of the reaction
Endergonic reaction: energy required
Amount of
energy
required
(G > 0)
Potential Energy vs. Kinetic
Energy
Types of work
performed by
living cells
Pi
P
Motor protein
Protein moved
Mechanical work: ATP phosphorylates motor proteins
Membrane
protein
ADP
+
Pi
ATP
Pi
P
Solute transported
Solute
Transport work: ATP phosphorylates transport proteins
P
NH2
Glu
+
NH3
+
Pi
Glu
Reactants: Glutamic acid
and ammonia
Product (glutamine)
made
Chemical work: ATP phosphorylates key reactants
ATP
Phosphorylation
Proteins
R groups of Amino Acids
2’ structure
3’ Structure
Proteins
involved in
constructing a
red blood cell
Quaternary
Structure
Polypeptide
chain
b Chains
Iron
Heme
Polypeptide chain
Collagen
a Chains
Hemoglobin
.
Substrate
Active site
Enzyme
Enzyme-substrate
complex
.
Substrates enter active site; enzyme
changes shape so its active site
embraces the substrates (induced fit).
Substrates held in
active site by weak
interactions, such as
hydrogen bonds and
ionic bonds.
Substrates
Enzyme-substrate
complex
Active
site is
available
for two new
substrate
molecules.
Enzyme
Products are
released.
Substrates are
converted into
products.
Products
Active site (and R groups of
its amino acids) can lower EA
and speed up a reaction by
• acting as a template for
substrate orientation,
• stressing the substrates
and stabilizing the
transition state,
• providing a favorable
microenvironment,
• participating directly in the
catalytic reaction.
.
Free energy
Course of
reaction
without
enzyme
EA
without
enzyme
EA with
enzyme
is lower
Reactants
Course of
reaction
with enzyme
G is unaffected
by enzyme
Products
Progress of the reaction
Optimal Performance
Denaturation of a protein
.
A substrate can
bind normally to the
active site of an
enzyme.
Substrate
Active site
Enzyme
Normal binding
A competitive
inhibitor mimics the
substrate, competing
for the active site.
Competitive
inhibitor
Competitive inhibition
A noncompetitive
inhibitor binds to the
enzyme away from the
active site, altering the
conformation of the
enzyme so that its
active site no longer
functions.
Noncompetitive inhibitor
Noncompetitive inhibition
Reaction rates for each condition
.
Allosteric enzyme
with four subunits
Regulatory
site (one
of four)
Active site
(one of four)
Activator
Active form
Oscillation
Nonfunctional
active site
Allosteric activator
stabilizes active form.
Inactive form
Stabilized active form
Allosteric inhibitor
stabilizes inactive form.
Inhibitor
Allosteric activators and inhibitors
Stabilized inactive
form
Feedback
Inhibition or
Negative
Feedback
Initial substrate
(threonine)
Active site
available
Isoleucine
used up by
cell
Threonine
in active site
Enzyme 1
(threonine
deaminase)
Intermediate A
Feedback
inhibition
Enzyme 2
Active site of
enzyme 1 can’t
bind
Intermediate B
theonine
pathway off
Enzyme 3
Isoleucine
binds to
allosteric
site
Intermediate C
Enzyme 4
Intermediate D
Enzyme 5
End product
(isoleucine)
.
Binding of one substrate molecule to
active site of one subunit locks all
subunits in active conformation.
Substrate
Inactive form
Stabilized active form
Cooperativity another type of allosteric activation
Electron Transport chain
creating a concentration
gradient in a Thylakoid
Redox reaction
Energy Coupling
Light
between
energy
Photosynthesis and
Cellular Respiration
ECOSYSTEM
Photosynthesis
in chloroplasts
Organic+ O
molecules 2
Cellular respiration
in mitochondria
CO2 + H2O
ATP
powers most cellular work
Heat
energy
Cellular Energy
Is Oxygen present?
Photosynthesis and Cellular
Respiration chemical reactions
(Remember… conservation of
matter.)
6 CO2 + 12 H2O  C6H12O6 + 6 O2
+6 H2O + Heat
Photosynthesis
C6H12O6 + 6O2  6CO2 + 6H2O + Heat + Free E
Cellular Respiration
ATP Structure
Phosphorylation using Free energy
Redox reaction
Is Oxygen present?
Pyruvate
Conversion
MITOCHONDRION
CYTOSOL
NAD+
NADH
+ H+
Acetyl Co A
Pyruvate
Transport protein
CO2
Coenzyme A
Kreb’s Cycle Simplified
Actual Kreb’s Cycle
Electron Transport Chain is
located on the inner FOLDED
membrane
Electron Transport Chain
(Proteins are H+ Pumps)
“Building” the proton
concentration gradient
Glycolysis
Citric
acid
cycle
ATP
ATP
Inner
mitochondrial
membrane
Oxidative
phosphorylation:
electron transport
and chemiosmosis
ATP
H+
H+
H+
H+
Intermembrane
space
Cyt c
Protein complex
of electron
carriers
Q
IV
III
I
ATP
synthase
II
Inner
mitochondrial
membrane
FADH2
NADH + H+
2H+ + 1/2 O2
H2O
FAD
NAD+
Mitochondrial
matrix
ATP
ADP + P i
(carrying electrons
from food)
H+
Electron transport chain
Electron transport and pumping of protons (H+),
Which create an H+ gradient across the membrane
Oxidative phosphorylation
Chemiosmosis
ATP synthesis powered by the flow
of H+ back across the membrane
ATP Synthase Complex using
kinetic movement of H+ (protons)
Valence is important with
electronegativity
Series of Redox reaction
(Electron Transport chain)

NAD⁺ +2 electrons + H⁺ ion = NADH

FAD⁺ + 2 electrons + 2 H⁺ ions = FADH₂
“Making” of electron carriers
Electron Transport Chain is
is ALWAYS located on a membrane
Oxygen is at the end
Process of Cellular Respiration
Energy Investment Phase &
Phosphofructokinase
Energy Payoff Phase
Is Oxygen present?
Pyruvate
Conversion
MITOCHONDRION
CYTOSOL
NAD+
NADH
+ H+
Acetyl Co A
Pyruvate
Transport protein
CO2
Coenzyme A
Kreb’s Cycle Simplified
Actual Kreb’s Cycle
Electron Transport Chain is
located on the inner FOLDED
membrane
Electron Transport Chain
(Proteins are H+ Pumps)
“Building” the proton
concentration gradient
Glycolysis
Citric
acid
cycle
ATP
ATP
Inner
mitochondrial
membrane
Oxidative
phosphorylation:
electron transport
and chemiosmosis
ATP
H+
H+
H+
H+
Intermembrane
space
Cyt c
Protein complex
of electron
carriers
Q
IV
III
I
ATP
synthase
II
Inner
mitochondrial
membrane
FADH2
NADH + H+
2H+ + 1/2 O2
H2O
FAD
NAD+
Mitochondrial
matrix
ATP
ADP + P i
(carrying electrons
from food)
H+
Electron transport chain
Electron transport and pumping of protons (H+),
Which create an H+ gradient across the membrane
Oxidative phosphorylation
Chemiosmosis
ATP synthesis powered by the flow
of H+ back across the membrane
ATP Synthase Complex using
kinetic movement of H+ (protons)
.
Allosteric enzyme
with four subunits
Regulatory
site (one
of four)
Active site
(one of four)
Activator
Active form
Oscillation
Nonfunctional
active site
Allosteric activator
stabilizes active form.
Inactive form
Stabilized active form
Allosteric inhibitor
stabilizes inactive form.
Inhibitor
Allosteric activators and inhibitors
Stabilized inactive
form
Energy Payoff Phase
Is Oxygen present?
Energy Payoff Phase
Need to keep Glycolysis going
Alcohol Fermentation
Bacteria and Yeast
Lactic Acid Fermentation
Animals such as yourself
Miller Urey experiment
Proteins
Macromolecule
Utilization in
Cellular
Respiration
Amino
acids
Carbohydrates
Sugars GlycerolFatty
acids
Glycolysis
Glucose
Glyceraldehyde-3- P
NH3
Fats
Pyruvate
Acetyl CoA
Citric
acid
cycle
Oxidative
phosphorylation
Amino Acid Basic
Structure
a carbon
Amino
group
Carboxyl
group
Basic lipid Structure
Ester linkage
Fat molecule (triacylglycerol)
Negative Feedback
Phosphofructokinase
(Puts on the SECOND ATP)