2.13-NucleoTide Metabolism Flashcards Preview

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Flashcards in 2.13-NucleoTide Metabolism Deck (32)
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1
Q

What makes a deoxyribonucleotide? Hint: 3 parts… Also what are the bonds between nucleotides?

A

Deoxyribose, Organic base, and phosphate..PhosphoDiester Bonds

2
Q

What can Inosinate be converted to?

A

AMP and GMP

3
Q

What is the carbohydrate used for synthesis of nucleic acids? What is it derived from?

A

Ribose-5-Phosphate, the PPP pathway! WOW that is a BIG pathway, it’s coming up over and over!

4
Q

When creating DNA and RNA de novo, how are deoxyribonucleotides made?

A

FROM Ribonucleotides!

5
Q

What disease comes from a HGPRT (Hypoxanthine-Guanine Phosphoribosyl Transferase :) :) LONG NAME WINNER!!!) deficiency?

A

Lesch Nyhan

6
Q

What is the difference between a nucleotide and a nucleoside?

A

NucleoTide=base + sugar + Phosphate…..NucleoSIDE= just base+ sugar (the phosphate committed suicide)

7
Q

What are the suffixes for a nucleotide and a nucleoside respectively?

A

Nucleoside ends in= idine(pyrimIDINE) or sine(Purine)…….Nucleotide ends in ylate (LIKE as in phosphorYLATE. get it?!)

8
Q

What are the two building blocks for salvage nucleotides?

A

Activated ribose (PRPP) + base

9
Q

What are the 5 building blocks for de novo nucleotides?

A

Activated Ribose (PRPP) + AAs + ATP + CO2 + NH3

10
Q

What is the RATE LIMITING STEP in PRPP synthesis? Enzyme? Which pathways is are PRPP involved with?

A

Ribose-5-Phosphate—–>PRPP (PhosphoRibosyl-1-PyroPhosphate). Enzyme PRPP Synthase…… PRPP INVOLVED IN EVERYTHING! Purine AND Pyrimidine, de novo AND Salvage pathways!

11
Q

What is the committed step in Purine Synthesis? What is the enzyme?

A

PRPP—->5-Phosphoribosyl-1-Amine….Enzyme=PRPP AmidoTransferase

12
Q

What is PRPP AmidoTransferase (enzyme in committed step of purine syn) stimulated by?

A

PRPP (Substrate of the Rxn)

13
Q

What is PRPP AmidoTransferase (enzyme in committed step of purine syn) allosterically inhibited by?

A

LOTS! ATP, ADP, and AMP at one site and GTP, GDP, GMP at another

14
Q

What process turns IMP to AMP?

A

Amination

15
Q

What two process turn IMP to GMP?

A

Oxidation then Amination

16
Q

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?

A

Adenylate Kinase and Guanylate Kinase…In the cytosol

17
Q

What molecules regulate the conversion of 5 PhosphoRibosylAmine to AMP and GMP? SLAM DUNK better get all three

A

AMP, GMP, IMP

18
Q

What is a mutant Purine associated with Inosate? (and made in outer space)

A

Hypoxanthine

19
Q

What are the three main disease conditions we discussed for the breakdown of Purines?

A

Severe Combined Immunodeficiency Disease (SCID), Gout, and Lesch-Nyhan

20
Q

What is the dysfunctional enzyme in SCID?

A

Adenosine DeAminase (converting Adenosine to Inosine)

21
Q

What causes Gout? What fixes Gout (name the enzyme at play)?

A

Overproduction of Uric Acid.. Allo-Purin-ol BLOCKS Xanthine Oxidase from making Uric Acid!

22
Q

What are the two enzymes necessary for Purine salvage?

A

APRT & HGPRT

23
Q

What is the enzyme deficiency associated with Lesch-Nyhan Syndrome? Which two bases can you not SALVAGE? What is the main physical manifestation?

A

HGPRT, so no Hypoxantine or Guanine. Pt will do self mutilation

24
Q

Where is CPSI found? Where is CPSII found?

A

CPS1 found in the Matrix (Urea Cycle) and CPSII found in the Cytosol (Pyrimidine Synthesis)

25
Q

What is the parent molecule in Pyrimidine Syn? Is the ring closed before or after this parent molecule is made?

A

OMP (Orotidylate). Ring is closed right before OMP made.

26
Q

What is the enzyme that converts RNA nucleotides to DNA nucleotides?

A

RiboNucleate Reductase (Need a little RNR?!)

27
Q

What molecule does our friend RNR need to do its job? What enzyme reduces this molecule?

A

Thiordoxin…Thiordoxin Reductase

28
Q

What are the three enzymes used in the salvage of pyrimidines? hint: think of the three pyrimidines

A

deoxyCytidine kinase, Uridine Kinase, Thymidine Kinase

29
Q

What is the molecule that salvages pyrimidines after they are phosphoylated in the cell? Not significant

A

pyrimidine phosphoribosyltransferase

30
Q

Uric acid is a product of ______ catabolism

A

purine

31
Q

CPS 1

A

urea cycle in mitochondria in liver

32
Q

CPS 2

A

purine synthesis