TCA cycleTCA cycle Tri carboxylic acid cycle : is called so

because several of its metabolites have three carboxyl group (citrate ,cis-aconitate ,isocitrate) .

Also called Kreb-cycle

Cycle of energy production, central cycle in the metabolisim of CHO, fatty acid and amino acid.

TCA cyclePrimary function of this cycle is energy production and final metabolites are CO2 and H2O .

Pyrovate which is the end product of glycolytic pathway is converted to acetyl coA as in the reaction pyruvate dehydrogenas + FAD

Pyruvate Acetyl coA +CoA-SH +CO2 +NADH

+NAD

TCA cycleSteps of TCA cycle Citrate synthetase Oxaloacetate Citrate + acetyl CoA CH2COOH | HO-COOH | CH2COOH

TCA cycle Aconitase Citrate Cis-aconitate H2O CH2COOH | C- COOH || CH-

COOH

TCA cycle

Aconitase Cis-aconitate Iso-citrate H2O CH2COOH | CH-COOH | HO-CH-COOH

TCA cycle

Isocitrate dehydrogenase Isocitrate Oxalosuccinate

+ NAD + NADH

TCA cycle

Isocitrate dehydrogenase Oxalosuccinate α-

ketoglutyrate CO2

TCA cycle

α-ketoglutyrate dehydrogenase complex α-ketoglutyrate succinyl CoA + CoA-SH CO2 + NAD + NADH

TCA cycle

Succinate Thiokinase Succinyl CoA Succinate Mg CoA-SH +ADP + ATP

TCA cycle

Succinate dehydrogenase

Succinate Fumerate + FAD + FADH

TCA cycle

Fumarase Fumarate Malate H2O

TCA cycle

Malate dehydrogenase Malate Oxaloacetate + NAD + NADH