phosphorylation
DESCRIPTION
Phosphorylation. When glucose enters a cell, a phosphate group (from ATP) gets attached to C #6. C 6 H 12 O 6 + PO 4 glucose-6-phosphate. All glucose inside a cell must be in the form of gluc-6-phos in order to be used. Non-reversible process in all except LIVER CELLS. - PowerPoint PPT PresentationTRANSCRIPT
When glucose entersa cell, a phosphate group(from ATP) gets attachedto C #6.
Phosphorylation
C6H12O6 + PO4 glucose-6-phosphate
All glucose inside a cellmust be in the form ofgluc-6-phos in order tobe used.
Non-reversible processin all except LIVER CELLS.
Glycogenesis
Glucose is stored asGLYCOGEN (long chains of gluc-6-phosmolecules)
“genesis” = formation
Glycolysis
Gluc-6-phos + 2ATP Pyruvate + 4ATP
Anaerobic processhttp://www.science.smith.edu/departments/Biology/Bio231/glycolysis.html
“lysis” = breaking apart
Glucose H- C = O | H - C - OH |HO- C - H | H - C - OH | H - C - OH | H - C - OH H
Pyruvate (Pyruvic acid)
CH3 - C – COOH || O
Kreb’s Cycle
• Pyruvic acid (from glycolysis) goes into the mitochondria
• CO2 + H+ are split off and
leaves a 2 carbon (acetyl)Group http://www.science.smith.edu/departments/Biology/Bio231/krebs.html (step 1)
• Acetyl group combines w/ CoA acetyl CoA
Coenzyme
Organic compound made by cells that must combine with an enzyme in order to work.
Coenzyme may be a hydrogen “carrier”
Hydrogen carriers
NAD – nicotinamide
adenine
dinucleotide
FAD – flavin adenine dinucleotide
NAD + H+ NADH+
FAD + H+ FADH+
Coenzyme A
Coenzyme that is NOT a hydrogen carrier.
Coenzyme A carries a 2-carbon (acetyl) group
ADP
Is also a coenzyme – carries phosphate groups
First part of Kreb’s cycle
CoA carries acetyl groupsinto the Kreb’s cycleto transfer them to oxaloacetic acid toform CITRIC ACID (nameof cycle) http://www.science.smith.edu/departments/Biology/Bio231/krebs.html (step 2)
Kreb’s cycleis important inthe metabolism of:
• Carbohydrates• Proteins• Lipids
In one “turn” of the Kreb’s cycle…..
• 2 molecules CO2
• 4 molecules H2 (3 NADH + 1FADH)
1 molecule acetyl CoA
•1 molecule ATP
And, now for the Kreb’sCycle itself………
From glycolysis
CH3 – C – COOH || O
+ CoA
CH3 – C – CoA || OAcetyl CoA
Pyruvic acid
Step #1CH3 – C – CoA || O acetyl CoA
COOH |C = O |CH2
|COOHoxaloacetic acid
COOH | CH2
|HO – C – COOH | CH2
| COOH citric acid
NADNADH+
Animationhttp://www.science.smith.edu/departments/Biology/Bio231/krebs.html
(step 2)
Step #2 COOH | CH2
|HO – C – COOH | CH2
| COOH citric acid
COOH | CH2
| C – COOH || CH | COOH cis-aconitic acid(unstable intermediate)
COOH | CH2
| C – COOH || CH | COOH cis-aconitic acid(unstable intermediate)
Step #3
COOH | CH2
| H - C – COOH | HO - CH | COOH isocitric acid
Step #4 COOH | CH2
| H - C – COOH | HO - CH | COOH isocitric acid
COOH | CH2
| H - C – COOH | C = O | COOH oxalosuccinic acid
-2H
Step #5 COOH | CH2
| H - C – COOH | C = O | COOH oxalosuccinic acid
COOH | CH2
| CH2 | C = O | COOH -ketoglutaric acid
-CO2
Step #6 COOH | CH2
| CH2 | C = O | COOH -ketoglutaric acid
COOH | CH2
| CH2 | C = O | CoA succinyl CoA
-CO2
-2H
NADH+NAD
Step #7 COOH | CH2
| CH2 | C = O | CoA succinyl CoA
COOH | CH2
| CH2 | COOHsuccinic acid
+H2O
NADNADH+
Step #8 COOH | CH2
| CH2 | COOHsuccinic acid
COOH | CH || CH | COOH fumaric acid
-2H
Step #9 COOH | CH || CH | COOH fumaric acid
COOH | HO - CH | CH2 | COOH malic acid
+H2O
Step #10 COOH | HO - CH | CH2 | COOH malic acid
COOH | C=O | CH2 | COOH oxaloacetic acid(back to where we started!)
-2H
Animation Summaryhttp://www.science.smith.edu/departments/Biology/Bio231/krebs.html
(step 3)
Summary to end of Kreb’s Cycle
In Out
1 pyruvic acid 1 CO2 (as waste)
1 NAD 1 NADH
CoA Acetyl CoA
1 acetyl CoA 2 CO2 (as waste)
3 NAD 3 NADH
1 FAD 1 FADH2
1 ADP 1 ATP
What happens to the CO2 produced in the Kreb’s Cycle?
Diffuses from mitochondria cytoplasm (cytosol) bloodstream exhaled (whew!)
Electron Transport ChainThe pairs of hydrogen ions (-2H) fromthe Kreb’s Cycle enter the electrontransport chain.
There are a series of HYDROGENACCEPTORS (NAD, FAD & cytochromes)that, as they pass the hydrogen ions along, ATP is being produced.
What ultimately happens to pairs of H?
Oxygen is final acceptor of H produces H2O!
From 4 pairs of H 36-38 ATPs produced inthe electron transport chain!
Glucose ATP count?
Phosphorylation & glycolysis: 8 ATP
Kreb’s cycle & electron transport: 30 ATP
Total = 38 ATPs
Electron Transport Chain(Animation)
http://www.science.smith.edu/departments/Biology/Bio231/etc.html
Fat metabolism1 unit of FAT
3 fatty acids 1 glycerol
18 C each chain glycolysis
Kreb’s cycle & electron transport
38 ATP
Each 18 C 6 pyruvic acidSo total of 18 pyruvic acids
18 pyruvic acids 684 ATP
So, 684 + 38 = 722 ATPs!
What about protein?
Single amino acids are used to buildmuscle, bones, connective tissue, and cytoplasm and cell membraneof cells.
Not typically catabolized (broken down)for energy – only during starvation.
22 amino acids – 8 are “essential”
Chemistry of Digestion writing prompt:
The carbohydrates, proteins and lipids have now been broken down into
single sugars, amino acids or fatty acids and glycerol. They are now in the liver.
Describe, in detail, the process by which glucose creates ATP and then how the other substances
become ATP as well. Be sure to include structures to
help your explanation.