Catabolism Of Pyruvate Flashcards
Where does the TCA cycle occur
Glycolysis - cytosol outside mito
tCA - matrix between Cristae
How does pyruvate enter the mitochondrial matrix
The hydrogen gradient from cytosol To matrix
Pyruvate transporter via facilitated diffusion
A similar process regulates ADP ATP and Pi movement in and out of mito
How is pyruvate metabolised to acetyl-CoA
The pyruvate dehydrogenase complex catalyses th oxidative decarboxylation of pyruvate to acetyl coA
PDC consist of 3 enzymes and is allosterically regulated by phosphorylation
PDC activity determines glucose oxidation in well oxygenated tissues
Reaction is irreversible
Give a brief overview of the TCA cycle
8 reactions 2C condenses with 4C The 6C made is decarboxylated twice Four oxidation reactions One GTP formed Recreat 4C
Describe the PDC deficiency
Deficiency on X chromosome Presents largely as neurological children disease Poor muscle tone Retardation Seizures Lactic acidosis RESP problems Brain lesions
Describe the fumerate hydrated deficiency and hereditary leiomyomatosis and renal cell cancer
Defect in fumerate hydratase
Multiple systemic benign and malignant metastasis
Link between TCA and cell prolif
How is the redox balanc maintained
Only limited amounts of NAD are present in a cell
Glycolysis reduces NAD to nADH and h
NADH must be reoxidised for glycolysis to continue
