2.13-NucleoTide Metabolism Flashcards
What makes a deoxyribonucleotide? Hint: 3 parts… Also what are the bonds between nucleotides?
Deoxyribose, Organic base, and phosphate..PhosphoDiester Bonds
What can Inosinate be converted to?
AMP and GMP
What is the carbohydrate used for synthesis of nucleic acids? What is it derived from?
Ribose-5-Phosphate, the PPP pathway! WOW that is a BIG pathway, it’s coming up over and over!
When creating DNA and RNA de novo, how are deoxyribonucleotides made?
FROM Ribonucleotides!
What disease comes from a HGPRT (Hypoxanthine-Guanine Phosphoribosyl Transferase :) :) LONG NAME WINNER!!!) deficiency?
Lesch Nyhan
What is the difference between a nucleotide and a nucleoside?
NucleoTide=base + sugar + Phosphate…..NucleoSIDE= just base+ sugar (the phosphate committed suicide)
What are the suffixes for a nucleotide and a nucleoside respectively?
Nucleoside ends in= idine(pyrimIDINE) or sine(Purine)…….Nucleotide ends in ylate (LIKE as in phosphorYLATE. get it?!)
What are the two building blocks for salvage nucleotides?
Activated ribose (PRPP) + base
What are the 5 building blocks for de novo nucleotides?
Activated Ribose (PRPP) + AAs + ATP + CO2 + NH3
What is the RATE LIMITING STEP in PRPP synthesis? Enzyme? Which pathways is are PRPP involved with?
Ribose-5-Phosphate—–>PRPP (PhosphoRibosyl-1-PyroPhosphate). Enzyme PRPP Synthase…… PRPP INVOLVED IN EVERYTHING! Purine AND Pyrimidine, de novo AND Salvage pathways!
What is the committed step in Purine Synthesis? What is the enzyme?
PRPP—->5-Phosphoribosyl-1-Amine….Enzyme=PRPP AmidoTransferase
What is PRPP AmidoTransferase (enzyme in committed step of purine syn) stimulated by?
PRPP (Substrate of the Rxn)
What is PRPP AmidoTransferase (enzyme in committed step of purine syn) allosterically inhibited by?
LOTS! ATP, ADP, and AMP at one site and GTP, GDP, GMP at another
What process turns IMP to AMP?
Amination
What two process turn IMP to GMP?
Oxidation then Amination
Do to the fact that that we want equal amounts of AMP, ADP, and ATP in our cells, what enzymes PHOSPHORYLATE AMP and GMP to make this happen? Where does it happen?
Adenylate Kinase and Guanylate Kinase…In the cytosol
What molecules regulate the conversion of 5 PhosphoRibosylAmine to AMP and GMP? SLAM DUNK better get all three
AMP, GMP, IMP
What is a mutant Purine associated with Inosate? (and made in outer space)
Hypoxanthine
What are the three main disease conditions we discussed for the breakdown of Purines?
Severe Combined Immunodeficiency Disease (SCID), Gout, and Lesch-Nyhan
What is the dysfunctional enzyme in SCID?
Adenosine DeAminase (converting Adenosine to Inosine)
What causes Gout? What fixes Gout (name the enzyme at play)?
Overproduction of Uric Acid.. Allo-Purin-ol BLOCKS Xanthine Oxidase from making Uric Acid!
What are the two enzymes necessary for Purine salvage?
APRT & HGPRT
What is the enzyme deficiency associated with Lesch-Nyhan Syndrome? Which two bases can you not SALVAGE? What is the main physical manifestation?
HGPRT, so no Hypoxantine or Guanine. Pt will do self mutilation
Where is CPSI found? Where is CPSII found?
CPS1 found in the Matrix (Urea Cycle) and CPSII found in the Cytosol (Pyrimidine Synthesis)
