lipid catabolism
DESCRIPTION
LIPID CATABOLISM. lipid menagerie. phospholipid. triglyceride. from McDonalds to Metabolism…. fig17-1. from McDonalds to Metabolism…. The chylomicron: a lipoprotein. fig17-2. mobilization of glycerol. fig17-4. connecting the FA to CoA-SH. fig17-5. connecting the FA to CoA-SH. - PowerPoint PPT PresentationTRANSCRIPT
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Lecture 12 Slides
part II intro fig4
Anabolism!!!
Gluconeogenesis
anabolic production of glucose
fig 14-16
Carbohydratesa two-lane highway…
what determinesthese specialsteps?
The glycolysis energy landscape
(pyruvate set to 0)
fig 14-17
First bypass
fig 14-17
First bypass, second step PEPCK
The glycolysis energy landscape
(pyruvate set to 0)
Three big steps down… or up
table 14-2
fig 14-17
First bypass
WHICHTISSUEScan do
GLUCONEOGENESIS?
fig 15-20
WHICH TISSUES can do GLUCONEOGENESIS?
1) LIVER
2) KIDNEY
fig 15-20
WHICH TISSUES can do GLUCONEOGENESIS?
1) LIVER
2) KIDNEY
fig 14-16 top
Three big steps on theway up…
fig 15-20
HOW DOES THE LIVER DECIDE WHETHER TO DO
GLUCONEOGENESISor GLYCOLYSIS?
fig 15-20
Two fates for pyruvate regulation by AcCoA abundance
Fructose bisphosphate is at a key position in both cat and ana
fig 15-15
Remember regulation of PFK-1??
pg 581
fig15-16
When glucose is abundant, so is F2,6BP
F2,6BP acceleratesPFK-1
fig 15-16
When glucose is low, so is F2,6BP
F2,6BP inhibitsFBPase
fig 15-16
When glucose is low, so is F2,6BPWhen glucose is abundant, so is F2,6BP
fig 15-17
Separate distinct enzyme activities control Fr2,6BP levels
fig 15-17
…and hormones control these enzymes
fig 15-20
WHAT ARE THECARBON SOURCE(S)
FOR GLUCONEOGENESIS?
fig 15-20
CARBON SOURCE(S) FOR GLUCONEOGENESIS?
1) Lactate
fig 15-20
CARBON SOURCE(S) FOR GLUCONEOGENESIS?
2) Glycerol
lipid menagerie (BLAST from the PAST)
phospholipid
triglyceride
fig 15-20
CARBON SOURCE(S) FOR GLUCONEOGENESIS?
3) Amino acids
table 14-4
CAN WE USEFATTY ACIDS
for GLUCONEOGENESIS?
Can you make glucose from fat using Krebs?
Fat breakdown produces AcCoA (later…)
Krebs cycle converts AcCoA to OAA
OAA can be converted to PEP (PEP-CK)
PEP is the rate-limiting step for synthesis ofglucose (later…)
so, why not?
every time you put an acetate intwo CO2 come out before you get to OAA!
fig 16-13
KREBS! (BLAST from the PAST)
CAN ANY ORGANISM USE
FATTY ACIDS for
GLUCONEOGENESIS?
fancy
The Glyoxylate Cycle
fig 16-20
Glyoxylate Cycle:
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anend runaround carbonloss
isocitratelyase
malate synthase
Plants: the Kings of Glyoxylate…
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Glyoxylate cycle: a cellular biochemist’s view…
fig 16-22 (sort of)
Glyoxylate cycle: a cellular biochemist’s view…
fig 16-22
Glyoxylate cycle: a cellular biochemist’s view…
fig 16-22
Glyoxylate cycle: a cellular biochemist’s view…
fig 16-22
The Biochemical Bottom Line:
fig 16-22
Acetyl-CoA + 3 NAD+ + FAD + GDP + Pi + 2 H2O→
CoA-SH + 3 NADH + 3 H+ + FADH2 + GTP + 2 CO2
Krebs
2 Acetyl-CoA + NAD+ → succinate + NADH + H+
Glyoxylate
Speaking of plants..
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RUBISCO: ribulose
Plants make glucose from… CO2 by photosynthesis
Optical processes (light-dependent reactions) generate ATP and NADPH by use of electron transport and H+ gradients
Biochemical reaction “fixes” CO2 to make 3 carbon precursor…
RUBISCO: ribulose-bis-phosphate carbolxylase
Plants use gluconeogenesis to make glucose from the 3PG made by rubisco…
3PG 1,3bPG
G3P
DHAP
Fr1,6bP etc
ATP and NADPH are employed as the expected substrates
in this process