Biochemistry Lecture 15 - Glycolysis Flashcards
In which two cells is glycolysis “especially important?”
RBCs and muscle cells.
Why is glycolysis so important in RBCs?
They lack mitochondria and glycolysis is their only source of ATP.
What is the overall net glycolytic reaction under areobic conditions?
Glucose + 2Pi +2ADP + 2NAD+ –> 2Pyruvate + 2NADH + 2ATP + 2H+ + 2H2O
What is the purpose of conversion of pyruvate to lactate?
Under aerobic conditions, there must be regeneration of NAD+ to continue making ATP.
How many ATPs are gained per round of glycolysis?
2
Where does glycolysis occur?
cytoplasm
After muscle cells and RBCs produce lactate, what happens to the lactate?
It is transported to the liver for conversion back to glucose.
What enzyme deficiency is common in RBCs and what does it result in?
Pyruvate kinase deficiency results in anemia.
What is a common muscle cell enzyme deficiency that causes exercise intolerance?
PFK-1 deficiency.
What is the main function of NAD+?
To support bio oxidations (it gets reduced in this process to NADH)
What is the ratio of NAD+/NADH in cells typically?
It is HIGH.
What disease can result from niacin deficiency?
Pellagra (3 or 4 D’s - dementia, diarrhea, dermatitis, sometimes death)
How many electrons and hydrogens can NAD+ accept?
2 electrons and 1 Hydrogen
What enzyme is involved in the conversion of pyruvate to lactate in anaerobic conditions to regenerate NAD+?
Lactate dehydrogenase.
What is common of the regulatory steps in the glycolytic pathway?
They have highly negative free energy changes.
