BCH210 FINAL EXAM
When is NADH/FADH2 produced?
- Glycolysis step 6 (2 per glucose)* becomes FADH in mitochondria
- PDH (2 per glucose)
- CAC NADH: Isocitrate dehydrogenase, alphaketoglutarate dehydrogenase
complex, malate dehydrogenase (3 per cycle, 6 per glucose)
- CAC FADH2: Succinate dehydrogenase (1 per cycle, 2 per glucose)
Total per glucose in oxidative phosphorylation: 8 NADH, 4 FADH2
When is H2O produced/used?
- Glycolysis: 2 H2O per glucose
- CAC: 1 used in step 1, 1 used in step 7 (-2 per cycle, -4 per glucose)
- ETC/ATP synthase: 3.5 made per NADH, 2.5 per FADH (in regular cycle = 38)
Total per glucose after glycolysis, CAC, ETC, and ATP synthase: 36 H2O
When is ATP/GTP produced/used?
- Glycolysis: 2 used in steps 1 and 3, produced in step 7 and 10 (1 in each step, 4
total per glucose) --> net 2 per glucose
- CAC: GTP produced (1 per cycle, 2 per glucose) in step 5
,- ETC/ATP synthase: 2.5 made per NADH, 1.5 per FADH
Total per glucose after glycolysis, CAC, ETC, and ATP synthase: 30 ATP
Triacylglycerol
A lipid consisting of three fatty acids linked to one glycerol molecule; also called a
fat or triglyceride.
Fat cell hormone signalling
Epinephrine and glucagon signal via GPCRs to activate triglycerol lipase/hormone
sensitive lipase (HSL) (phosphorylation via PKA)
triacylglycerol lipase / hormone sensitive lipase (HSL)
Hydrolyzes ester bonds on TAGs producing free fatty acids (ususally 16:0).
Hydrolyzes one ester bond at a time (used 3 times to break down one TAG).
Phosphorylated + activated by PKA glucagon/epinephrine (GPCR) signaling
albumin
Protein that can carry free fatty acids through the blood. Can bring FFAs to all cells
(except brain) for beta oxidation
Acyl CoA Synthetase
Covalently adds CoA onto fatty acid chains to trap them in the cytosol. uses ATP
(→AMP), and subsequent hydrolysis of PPi + H2O -> 2 Pi is favourable and helps
,provide energy for overall reaction. Requires 2 ATP (one in reaction, one to
regenerate ADP from AMP)
Adenylate kinase
ATP + AMP <--> 2 ADP (ADP --> ATP then done by ATP synthase)
Carnitine Shuttle
Mechanism for moving fatty acids from the cytosol to the mitochondrial matrix as
fatty esters of carnitine. Regulates what comes into the mitochondria. Made of
CAT I, CAT II, and translocase.
Carnitine Acyltransferase I (CAT I)
Creates acyl carnitine from acyl CoA, which is then brought into matrix by
translocase in exchange for carnitine. Inhibited by malonyl CoA
Carnitine Acyltransferase II (CAT II)
Regenerates fatty acyl CoA using acyl from acyl carnitine (produces free carnitine
to be transported back out)
Beta oxidation
A metabolic sequence that breaks fatty acids down to two-carbon fragments that
enter the citric acid cycle as acetyl CoA. Each round takes 2 carbons off chain,
requires H2O, NAD+, FAD+, and a new CoA and produces NADH, FADH2, and 1
Acetyl CoA. Last round produces 2 Acetyl CoAs. Number of rounds in (#Cs in acyl
chain / 2) - 1.
, Beta oxidation: Acyl CoA dehydrogenase
Produces FADH2 (reduced) and creates a double bond in the fatty acid chain
(oxidized)
Beta oxidation: Hydratase
Adds water across the double bond
Beta oxidation: Dehydrogenase
Produces NADH and creates a keto group on
the β carbon in the chain
Beta oxidation: Thiolase
Uses CoA to release acetyl CoA from beta keto acid; producing a fatty acyl CoA
chain with 2 fewer carbons
Beta oxidation overall reaction
16:0 CoA + 7 NAD+ + 7 FAD + 7 H2O + 7 CoA --> 8 acetyl CoA + 7 NADH + 7 FADH2
+ 7 H+
Complete oxidation of a 16:0-CoA in the mitochondrial matrix
When is NADH/FADH2 produced?
- Glycolysis step 6 (2 per glucose)* becomes FADH in mitochondria
- PDH (2 per glucose)
- CAC NADH: Isocitrate dehydrogenase, alphaketoglutarate dehydrogenase
complex, malate dehydrogenase (3 per cycle, 6 per glucose)
- CAC FADH2: Succinate dehydrogenase (1 per cycle, 2 per glucose)
Total per glucose in oxidative phosphorylation: 8 NADH, 4 FADH2
When is H2O produced/used?
- Glycolysis: 2 H2O per glucose
- CAC: 1 used in step 1, 1 used in step 7 (-2 per cycle, -4 per glucose)
- ETC/ATP synthase: 3.5 made per NADH, 2.5 per FADH (in regular cycle = 38)
Total per glucose after glycolysis, CAC, ETC, and ATP synthase: 36 H2O
When is ATP/GTP produced/used?
- Glycolysis: 2 used in steps 1 and 3, produced in step 7 and 10 (1 in each step, 4
total per glucose) --> net 2 per glucose
- CAC: GTP produced (1 per cycle, 2 per glucose) in step 5
,- ETC/ATP synthase: 2.5 made per NADH, 1.5 per FADH
Total per glucose after glycolysis, CAC, ETC, and ATP synthase: 30 ATP
Triacylglycerol
A lipid consisting of three fatty acids linked to one glycerol molecule; also called a
fat or triglyceride.
Fat cell hormone signalling
Epinephrine and glucagon signal via GPCRs to activate triglycerol lipase/hormone
sensitive lipase (HSL) (phosphorylation via PKA)
triacylglycerol lipase / hormone sensitive lipase (HSL)
Hydrolyzes ester bonds on TAGs producing free fatty acids (ususally 16:0).
Hydrolyzes one ester bond at a time (used 3 times to break down one TAG).
Phosphorylated + activated by PKA glucagon/epinephrine (GPCR) signaling
albumin
Protein that can carry free fatty acids through the blood. Can bring FFAs to all cells
(except brain) for beta oxidation
Acyl CoA Synthetase
Covalently adds CoA onto fatty acid chains to trap them in the cytosol. uses ATP
(→AMP), and subsequent hydrolysis of PPi + H2O -> 2 Pi is favourable and helps
,provide energy for overall reaction. Requires 2 ATP (one in reaction, one to
regenerate ADP from AMP)
Adenylate kinase
ATP + AMP <--> 2 ADP (ADP --> ATP then done by ATP synthase)
Carnitine Shuttle
Mechanism for moving fatty acids from the cytosol to the mitochondrial matrix as
fatty esters of carnitine. Regulates what comes into the mitochondria. Made of
CAT I, CAT II, and translocase.
Carnitine Acyltransferase I (CAT I)
Creates acyl carnitine from acyl CoA, which is then brought into matrix by
translocase in exchange for carnitine. Inhibited by malonyl CoA
Carnitine Acyltransferase II (CAT II)
Regenerates fatty acyl CoA using acyl from acyl carnitine (produces free carnitine
to be transported back out)
Beta oxidation
A metabolic sequence that breaks fatty acids down to two-carbon fragments that
enter the citric acid cycle as acetyl CoA. Each round takes 2 carbons off chain,
requires H2O, NAD+, FAD+, and a new CoA and produces NADH, FADH2, and 1
Acetyl CoA. Last round produces 2 Acetyl CoAs. Number of rounds in (#Cs in acyl
chain / 2) - 1.
, Beta oxidation: Acyl CoA dehydrogenase
Produces FADH2 (reduced) and creates a double bond in the fatty acid chain
(oxidized)
Beta oxidation: Hydratase
Adds water across the double bond
Beta oxidation: Dehydrogenase
Produces NADH and creates a keto group on
the β carbon in the chain
Beta oxidation: Thiolase
Uses CoA to release acetyl CoA from beta keto acid; producing a fatty acyl CoA
chain with 2 fewer carbons
Beta oxidation overall reaction
16:0 CoA + 7 NAD+ + 7 FAD + 7 H2O + 7 CoA --> 8 acetyl CoA + 7 NADH + 7 FADH2
+ 7 H+
Complete oxidation of a 16:0-CoA in the mitochondrial matrix
