Wednesday, November 10, 2010
Final exam conflict for Monday 12/13 at 2PM?
Meet immediately after lecture
TODAY to choose date/time for make-up exam.
This discussion has now
The make-up final exam will be on Wednesday 12/15 at 9:00AM,
In order to take this make-up exam, you must be on “the prof’s list” of
eligible students (direct conflict with another final exam, or 2 other final exams
within 24 hours of the regular Monday 2PM exam).
If you are sick at the time of
the regular exam, e-mail the prof!
Friday 11/12 at 2:55 – 4PM in Comstock B108: Interviews for the HCEC and for
medical schools-- what are they looking for?!
FA entry into mitochondrial matrix is regulated
cells control [CoA] in each membrane-bound compartment
-oxidation of FA
"ketone bodies" as fuel for heart (and kidneys)
amino acid breakdown: transfer of amino group to alpha-KG, forming Glu
In the liver mitochondrial matrix, bicarbonate combines with the
phosphate of an ATP, then in a second step with an ammonium ion at the
expense of another ATP to form carbamoyl phosphate.
This can be called "Step
1" of the Urea Cycle (However, note that by definition of a cycle, the starting
substrate reacts with the final product.
For that reason, textbook authors usually
“don’t count” the formation of carbamoyl phosphate as a step of the Urea Cycle!).
carbamoyl phosphate synthetase
, accounts for about 1/4 of the
protein in the liver mitochondrial matrix!
Wow that's a lot, considering all the
other enzymes in the matrix (PDH, CAC).
The overall reaction is a cycle-- the first reactant combines with the last product:
Carbamoyl phosphate, the first reactant, combines with ornithine, the last
product, also in the matrix, to form citrulline and P
Citrulline is transported across the inner mitochondrial membrane.
Citrulline then combines with ATP and Asp in the third reaction to form
This reaction and all the other reactions of the urea cycle
occur "in the cytosol", but in fact, the enzymes for these reactions are all