Download THE CITRIC ACID CYCLE - Universitas Airlangga

THE CITRIC ACID CYCLE
Kadek Rachmawati
 The citric acid cycle = Kreb’s cycle = Tricarboxy lic acid cycle
a series of reactions that
oxidized Asetyl-CoA
 Occur in Mitochondria
 To yield energy (ATP)
 TCA cycle
the final common pathway for the
aerobic oxidation of carbohydrate, lipid and
protein
TCA cycle is common pathway for
carbohydrate, lipid and protein
TCA cycle pathway
The function of TCA cycle :
 1. Oxidized of Acetyl CoA
ATP
( 1 mol Acetyl CoA
12 mol ATP )
 2. The citric acid cycle is AMPHIBOLIC :
- it can oxidized to yield ATP
- it is important in the provision of carbon
skeletons for gluconeogenesis, fatty acid
synthesis and interconversion of amino acid
Vitamins play key roles of the Citric Acid Cycle
 Four of the B vitamins are essential in the citric
acid cycle :
1. Ribovlavin
FAD
2. Niacin
NAD
3. Thiamin
TPP
4. Pantothenic acid
CoA
 The B vitamins are essential in energy yielding
metabolism by dehydrogenase enzyme :
- FAD
2 mol ATP
- NAD
3 mol ATP
INHIBITOR OF TCA CYCLE
1. Fluoroacetate
• Condensation with CoA
Fluoroacetyl-CoA
• Condensation FluoroacetylCoA with Oxaloacetate
Fluorocitrate
inhibit Akonitase enzyme
accumulation of citrate
• Fluoroacetate
pesticide
2. Malonate
suksinat dehydrogenase
enzyme
3. Arsenite
α-ketoglutarate dehydrogenase enzyme
Participation of TCA cycle in fatty acid
synthesis from glucose
Involvement of TCA cycle in transamination
and gluconeogenesis
REGULATION OF TCA CYCLE
REGULATION OF TCA CYCLE
REGULATION OF TCA CYCLE
REGULATION OF TCA CYCLE