MCB 2000 Lecture Notes - Lecture 24: Pyruvate Carboxylase, Citric Acid Cycle, Acetyl-Coa
Document Summary
Citrate will exit mitochondria and be used for fatty acid synthesis in cytoplasm. Nadh, acetyl coa, oaa cannot cross mitochondrial membrane. Shuttles (indirect mechanisms, interconverted to other molecules) High requirement for synthesis of protoporphyrin ring. Oaa is rate-limiting intermediate in tca cycle. Oaa will condense with acetyl coa to make citrate, carbon skeleton used to produce glucose during gluconeogenesis, interchangeable with aspartic acid. Lling up reactions -> if diverting intermediates from tca cycle, they must be replaced. Nadh and fadh2 generated during reactions of tca will donate their electrons to the etc. Does not generate atp, but its activity is required for generation of atp (due to free energy changes); one does not happen without the other. Redox reactions -> electron carriers nadh and fadh2 reduce molecular oxygen (occurs through intermediate reactions) Complex 1 is very large, 46 subunits, has 2 prosthetic groups, iron-sulfur center. All complexes must have a transition metal center.
