Energy Production In Carbohydrates 4 Flashcards
Where does the pyruvate reaction take place?
Mitochondrial matrix
What reaction takes place in pyruvate reaction?
Pyruvate + CoA + NAD+ -> acetyl CoA + CO2 + NADH + H+
What enzyme is used in pyruvate reaction?
Pyruvate dehydrogenase
What provides the cofactors for PDH?
B vitamins, therefore reaction is sensitive to vitamin B1 deficiency
Is the pyruvate reaction reversible?
Reaction is irreversible
What can inhibit the pyruvate reaction?
Acetyl CoA
NADH
ATP
Citrate
What can activate the pyruvate reaction?
CoASH
NAD+
ADP
Insulin
What can a PDH deficiency result in?
Lactic acidosis
Where does the Krebs cycle take place?
Mitochondria
What happens in the Krebs cycle?
Acetyl is converted to 2CO2
Oxidative as requires NAD+ and FAD
Some energy is produced as ATP/GTP
What is produced in the Krebs cycle for every glucose molecule?
Krebs cycle occurs twice for each glucose molecule
6 NADH
2 FADH2
2 GTP
How is the Krebs cycle regulated in general?
Regulated by energy availability (ATP/ADP ratio, NADH/NAD+ ratio)
How is the Krebs cycle regulated at isocitrate to C5?
Isocitrate dehydrogenase enzyme used
Stimulated by ADP, inhibited by NADH and ATP
How is the Krebs cycle regulated at alpha-ketoglutarate (C5) to succinyl-CoA (C4)?
Alpha-ketoglutarate dehydrogenase enzyme used
Inhibited by NADH, ATP and succinyl-CoA
What is the Krebs cycle a central pathway for?
Catabolism of sugars, fatty acids, ketone bodies, amino acids and alcohol