Exam 2 Lecture #5 TCA Cycle Flashcards
How do pyruvate, fatty acids, and amino acids get turned into acetyl coA?
Pyruvate gets oxidized into acetyl coA (PDH)
Fatty Acids undergo Beta Oxidation to create acetyl CoA
Amino Acids get deaminated and oxidized to form acetyl coA
What are the four fates of pyruvate?
Pyruvate:
undergoes oxidation to create acetyl CoA
Gets transaminated to create alanine
Undergoes carboxylation to create oxaloacetate
gets reduced to form lactate
If you have a deficiency in the vitamin cofactors for PDH, which are ___________, then PDH complex will become_______
Vitamin deficiency in Thiamine (TPP, B1), Riboflavin (FAD, B2), or Niacin (NAD, B3) will cause PDH complex to be less active
What is the overview for the TCA cycle in terms of what you get out of it?
The TCA cycle:
you oxidize acetyl coA (essentially a combustion reaction), and get the production of 3 NADH, 1 FADH2, and 1 GTP
Where does the TCA take place?
The mitochondria, which is smart because the reduced electron carriers can then be in close proximity to the ETC
Explain the first step of the Krebs Cycle
The first step of the krebs cycle:
acetyl coA (which is a 2 carbon compound) combines with oxaloacetate (4 carbon compound) to create citrate (catalyzed by citrate synthase)
Draw the Krebs Cycle
Explain how the intermediates are replenished in the TCA
Identify the biosynthetic pathways for which the TCA cycle is intermediates for
What are the activators and inhibitors for the two most important enzymes in the TCA cycle
Explain the PDH defeciency
PDH defeciency: leads to increased lactate, pyruvate, alanine
Leads to lactic acidosis
Fumarase Deficiency
Can’t turn fumarase into malate
increased fumarate, succinate, alpha keto glutamate, and citrate in the urine
severe neurological impairment
What does fluroasetate/ rate poison do?
It inhibits iconitase and therefore inhibits the TCA cycle
