Younger Nucleotide Metabolism Flashcards
(37 cards)
Nucleotide functions:
Structural component: -DNA and RNA -Coenzymes (CoA, FAD, NAD+, NADP+) -Secondary messengers (cAMP) -Energy "currency" of the cell (ATP) -Regulators of many pathways (DONT NEED TO MEMORIZE, just correlate)
Features of Nucleotides:
Nitrogenous base and sugar
Nitrogenous base: Purines and Pyrimidines
CUT PY
Pyrimidines: Cytosine, Thymine (DNA) Uracil (RNA)
AG PU
Purines: Adenine and Guanine
Nucleotides sugar:
Ribose in RNA
Deoxyribose in DNA
Nucleoside=
Nitrogenous base + Sugar
Nucleotide=
Nucleoside + 1-3 phosphate groups
Be able to distinguish between ribonucleic acids and deoxyribonucleic acid.
Know that OH is in RNA and H in DNA
The ribose 5-phosphate is from what other pathway?
HMP shunt
What is the enzyme that catalyzes the formation of the activated pentose?
Activates the ribose by putting inorganic phosphate on it
PRPP synthetase
List the + and - regulators of PRPP synthetase
(+) Inorganic phosphate
(-) purine ribonucleotides
What carbon is pyrophosphate and nitrogenous base bound to?
1’ Carbon
What is the rate limiting step of production of purines, this is catalyzed by what enzyme?
PRPP amidotransferase (puts amine group on base)
What is a derivative of Folate?
THF (tetrahydrofolate)
Why is folate required in our diet?
We need it to modify it to make THF.
As long as you have ______ you are going to be activated and be producing purine (promoting the production of nucleotides).
PRPP Amidotransferase
What “drug” will inhibit PRPP amidotransferase?
6-Mercaptopurine
What drug is a folic acid, inhibits THF synthesis, and therefore is an anti-tumor drug?
Methotrexate (mammalian cells)
What drug is a structural analog of PABA (para aminobenzoic acid)?
Sulfonamides (sulfa drugs) they function as antibiotics
Whats the activator of PRPP? (rate limiting, committed step of pyrimidine synthesis)
CPS-II (carbamoyl phosphate synthetase II)
What activates and inhibits CPS-II?
(+) PRPP
-) UTP (also downstream products are inhibitors
PRPP provides the ________ for the pyrimidine.
pentose
Pyrimidine bases are produced then attached to ____.
PRPP
What else can hydroxyurea treat other than being an anti-tumor drug?
Sickle Cell Anemia because it promotes HbF synthesis
Does synthase need ATP to work?
no, synthetase does