1 / 16

ط      Citric acid cycle, Steps and enzymes ط      Regulatory steps of CAC ط      Energetic of CAC

Citric acid cycle (CAC). ط      Citric acid cycle, Steps and enzymes ط      Regulatory steps of CAC ط      Energetic of CAC D4 231-239  ,     L2  467-469. Citric Acid Cycle (CAC). CAC is for complete oxidation of Glu (CO 2 +H 2 O) & production of further ATP in mitoch. matrix (mitosol)

apollo
Download Presentation

ط      Citric acid cycle, Steps and enzymes ط      Regulatory steps of CAC ط      Energetic of CAC

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Citric acid cycle (CAC) ط     Citric acid cycle, Steps and enzymes ط     Regulatory steps of CAC ط     Energetic of CAC D4 231-239  ,     L2  467-469

  2. Citric Acid Cycle (CAC) CAC is for complete oxidation of Glu (CO2+H2O) & production of further ATP in mitoch. matrix (mitosol) fig6.18,  ATP is generated: by high-energy phosphate bond (1 GTP) + by reducing equivalent (3 NADH, 1 FADH2) in the elect-trans-oxid phosph sequence(mitosol) fig6.19, OA (4C) + ACoA (2C) CS-ase (–CoA)  "citroyl-SCoA as intermediate"C-ate (6C) A-tase "cis-Aconitate as intermediate" IsoC (6C) ICDH (+NADH/CO2) "oxalosuccinate as intermediate" α-KG (5C) α-KGDH (+NADH/CO2) SCoA (5C) SCoA S-tase (+GTP) "succinate phaphate as intermediate" S-ate (4C) SDH (+FADH2) F-ate (5C) F-aseM-ate (4C) MDH (+NADH/CO2) OA (4C) *Tricarboxylic Acid (TCA) cycle = Citric Acid Cycle (CAC) = Kreb's cycle

  3. Regulation and characters of Citric acid cycle ط     Inhibitors of  CAC ط     Amphibolic Nature of the cycle ط     Anapleorotic reaction of CAC ط     Reactions of CAC:  stoichametry of CAC                                     control of CAC ط     Clinical correlation                    Pyruvate Dehydrogenase deficiency                    Fumarase deficiency D4 231-239  ,     L2  467-469

  4. ACoA (2C) fate fig6.11,  a) A (acetyl) + CoA (β-ME + PA + A, R)  ACoA               b) Acetate + CoA AK (–ATP)  ACoA fig6.17,  AA, FA, Pyr     ACoA  KB (only in liver mitosol)  Cholesterol Citrate  Carbon Source of Sterols & FA biosynthesis (cytosol)  Source of Reducing Equivalent (cytosol)  Other Metabolic Pathways Allosteric Regulation (cytosol)  TCA cycle (mitosol)

  5. CAC Regulation fig6.23,   1. OA + ACoA CS-ase(–) by acylCoA, SCoA, NADH, ATP (+) by ACoA, OACitarate * fig 6.20, Citrate ===> Carbon Source / Reducing Equivalent Source / Allosteric Regulator

  6. CAC Regulation                 2. Citrate A-tase (–) by MFC-ate (aninhibitor) (+) by Fe2+ IsoCitrate * Isocitrate continues in CAC

  7. CAC Regulation                 3. IsoCitrate ICDH(–) by ATP, NADH (+) by AMP, ADP, NAD+, Ca2+α-Ketoglutarate * α-KG ===>    ammonia (urea) / AA metabolism (Glu = α-KG)

  8. CAC Regulation fig,  ICDH aPK (–) by IsoC, OA, Pyr, 3PG, PEP ICDH b ICDH bPP-tase (+) by IsoC, OA, Pyr, 3PG, PEP ICDH a

  9. CAC Regulation                 4. α-KG α-KGDH(–) by ATP, NADH, GTP, SCoA (+) by Ca2+ SCoA * fig 6.21, SCoA ===>    PCoA / heme biosynthesis / KB utilization

  10. CAC Regulation                 5. Succinyl CoA SCoA S-taseSuccinate * Succinate continues in CAC

  11. CAC Regulation 6. Succinate SDH(–) by OA, Malonate (an inhibitor) (+) by ATP, Pi, succinateFumarate * Fumarate ===>    ammonia (urea) / Glu = α-KG

  12. CAC Regulation 7. Fumarate Fumarase Malate * Malate ===>    FA synth (Citrate) / Glu (OA)

  13. CAC Regulation 8. Malate MDH(–) by NAD+ (+) by OAOA * OA ===>    Pyr (PEP) / Asp (Pyrimidines)

  14. fig, Anaplerotic reaction (CAC): Pyr Pyr C-lase (-CO2/ATP) OAPEP C-lase (CO2/Pi)  PEP Pyr Malic Enz (NADPH)  M-ate MDH (NADH) OA

  15. Clinical Correlations Fumarase Deficiency: a)  Deficiency in in both cytosolic (bld lymphocytes) and in mitosolic. b)  High F-ate in urine & 1 more of C-ate, α-KG, S-ate, M-ate. c)  Sever neurological impairment, encephalopathy & Dystonia (soon after birth). d)  F-ase Deficiency is an autosomal recessive disorder (glu replaced by gln).

More Related