The TCA cycle,It’s Regulation
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TCA CYCLE
The citric acid cycle or TCA cycle is the central metabolic
pathway of the cell.
It is essentially involves the oxidation of acetyle CoA to CO2
and H2O.
TCA cycle is the final common oxidative pathway for
carbohydrate, fats and amino acids.
TCA cycle is also known as Krebs cycle.
In eukaryotes, the reactions of the citric acids cycle take
place inside mitochondria.
REGULATION OF THE KREBS CYCLE
The cycle begins when acetyl group from acetyl CoA is
attached to oxaloacetate to form citrate.
Then citrate is rearranged to an isomer called
isocitrate.
Isocitrate is oxidised to alfa-ketogluterate. CO2 is
released and NADH is formed.
alfa-ketogluterate is oxidised as it combines with CoA
to form succinyl CoA. Once again CO2 is released and NADH
is formed.
Succinyl CoA is then broken down to CoA and succinate.
Succinate is oxidised to fumarate.FADH2 is made.
Fumarate combines with water to make malate.
Malate is the oxidised to oxaloacetate.NADH is made. The
cycle can begin again.
SIGNIFICANCE OF TCA CYCLE
The citric acids cycle is not only a pathway for oxidation of
two carbon units, but also a major pathway for Transamination
and deamination of amino acids.
Providing the substrate for amino acids synthesis by
transamination as well as for gluconeogeneis and fatty acid
synthesis.
This is the general notes on TCA Cycle and It’s Regulation.
Thank you for reading.