LB145
Sec 001-004
Happy Valentine’s Day!
Today’s Announcements
• StudyNotes5 AND Homework4 are due on
Feb 19th.
• **Download HW VERSION 2.0**
• Field Trip sign up – started!
• Glycolysis and the Krebs Cycle.
• Oxidative Phosphorylation, the ETC.
Tuesday
Glycolysis: What do
you need to know?
Track the Carbons and Phosphates:
Glucose + ATP  Fructose-P + ADP
Fructose-P + ATP  P-Fructose-P
P-Fructose-P  P-CCC + P-CCC
P-CCC + P-CCC + 2NAD+ + 2Pi P-CCC-P + P-CCC-P + 2NADH
P-CCC-P + P-CCC-P + 2ADP  P-CCC + P-CCC + 2ATP
P-CCC + P-CCC + 2ADP  Pyruvate + Pyruvate + 2ATP
Methods of Producing ATP
GLYCOLYSIS & CITRIC ACID CYCLE
• Substrate-level phosphorylation occurs when ATP is
produced by the enzyme-catalyzed transfer of a
phosphate group from an intermediate substrate to
ADP.
Campbell: Fig. 9-6-3
Electrons carried
via NADH and
FADH2
Electrons
carried
via NADH
Citric
acid
cycle
Glycolysis
Pyruvate
Glucose
Oxidative
phosphorylation:
electron transport
and
chemiosmosis
Mitochondrion
Cytosol
ATP
ATP
ATP
Substrate-level
phosphorylation
Substrate-level
phosphorylation
Oxidative
phosphorylation
Fig. 9-10
CYTOSOL
MITOCHONDRION
NAD+
NADH
+ H+
2
1
Pyruvate
Transport protein
3
CO2
Coenzyme A
Acetyl CoA
Fig. 9-11
Pyruvate
CO2
NAD+
CoA
NADH
+ H+
Acetyl CoA
CoA
CoA
Citric
acid
cycle
2 CO2
FADH2
3 NAD+
3 NADH
FAD
+ 3 H+
ADP + P
ATP
i
Bitter Melon
Selling my Body to Science
1. Consume a cup of liquid glucose.
2. Consume capsules that contain
bitter melon OR placebo.
3. Lie still on a bed with a dome
over my head and allow breath
to be analyzed for an hour.
QUESTIONS:
Q1: On a molecular level, what is happening if bitter melon aids weight
loss?
Q2: On a molecular level, what is happening if bitter melon does not aid
weight loss?
Q3: Why were they interested in the air I exhaled?
Q4: What do you think might happen to excess glucose in your body?
Glycolysis is a core metabolic pathway!
Campbell 8e Fig. 9.16
ETC:
The main pieces
Complex I: NADH dehydrogenase
•removes e- from NADH
•pumps 4 H+ into intermembrane space
Complex II: succinate dehydrogenase Complex III: Cytochrome bc1
•moves e- from FADH2 to Q
•transfers e- from Q to Cyt c
•pumps 2 H+ into intermembrane space
Complex IV: cytochrome c oxidase
•transfers e- from Cyt c to O2
•pumps 2H+ into intermembrane space
Q: ubiquinone, pumps 2 H+
into intermembrane space
Cyt c: cytochrome c
•e- shuttles
Disrupting cellular respiration:
What happens if…..?
Disrupting cellular respiration:
What happens if…..?
• Cyanide
– Binds to Cytochrome oxidase
(Complex IV)
– Immediate Effect?
– Ultimate Effect?
Disrupting cellular respiration:
What happens if…..?
• Rotenone
– Binds to ubiquinone binding site of
Complex I
– Immediate Effect?
– Ultimate Effect?
Disrupting cellular respiration:
What happens if…..?
• Dinitrophenol
– Protonophore (makes membrane
completely permeable to H+ ions)
– Immediate Effect?
– Ultimate Effect?
Anaerobic Respiration
Anaerobic Respiration
(from wikipedia)
Homework Problem:
Question: The Glucose Problem
In the molecular process known as cellular
respiration, how many ATP molecules can be made
from the electron transport chain after one
molecule of glucose is catabolized in glycolysis,
pyruvate processing and the citric acid cycle.
Assume that 1 ATP is produced when 3.5 protons pass through ATP synthase.
**What pieces of information do I need to know to
solve this problem?
Problem solving…
Problem solving…
What would be the implications if a
mitochondria was missing Complex II?
Problem solving…
If Complex I was missing, what would net more
ATP: Krebs Cycle OR ETC?
Problem solving…
Can the ETC make energy (ATP) when we are not
breathing? Why or why not?
Problem solving…
Assume there was an unlimited supply of readily
available NADH and an unlimited supply of
readily available photons. If you had to choose
one of the below two processes to make ATP,
which would you choose (and why!)
For TUESDAY:
1. SN5 and HW4 (Version 2.0)
2. Honors Option Students – SIGN UP FOR THE
FIELD TRIP (and show me the money)