Purine and Pyrimidines

Question 1

What has to be activated in order for Purines to be made de novo?

Answer 1

ribose 5-phosphate

Question 2

IMP is formed from what 5 contributing groups?

Answer 2

Aspartate, Glycine, Glutamine, Formate, and Bicarb ion

Question 3

Ribose 5-phosphate is converted to what in Purine synthesis?

Answer 3

IMP

Question 4

IMP can be salvaged from what two ribonucleotides?

Answer 4

adenine and guanine

Question 5

IMP to GMP requires what?

Answer 5

1 ATP

Question 6

IMP to AMP requires what?

Answer 6

1 GTP

Question 7

What is the nitrogen donor in the conversion of IMP to GMP?

Answer 7

Glutamine –> be careful, don’t confuse with glutamate

Question 8

What is the nitrogen donor in the conversion of IMP to AMP?

Answer 8

Aspartate

Question 9

ATP induces what in GMP production?

Answer 9

Increases GMP prod.

Question 10

GTP production increases what?

Answer 10

AMP

Question 11

Purines can be salvaged from what interconversions?

Answer 11

free bases, nucelosides, and nucleotides

Question 12

In Lesch-Nyhan syndrome, a person is defective in what pathway?

Answer 12

Purine salvage

Question 13

In Lesch-Nyhan syndrome purines are converted to what substance?

Answer 13

Uric acid

Question 14

Adenosine Deaminase Deficiency is a deficiency in what pathway?

Answer 14

Purine salvage

Question 15

Adenosine deaminase is used in the conversion of adenosine into what?

Answer 15

Inosine

Question 16

Adenosine Deaminase Deficiency causes what?

Answer 16

Bubble Boy syndrome

The body isn’t able to produce T or B cells

Question 17

In purine synthesis, the base is made when?

Answer 17

While ATTACHED to sugar

Question 18

In pyrimidine synthesis, the base is made when?

Answer 18

It is made BEFORE it is attached to sugar

Question 19

Pyrimidine synthesis is inhibited by what?

Answer 19

UTP

Question 20

The source of nitrogen for pyrimidine synthesis comes from what?

Answer 20

Glutamine

Question 21

Pyrimidine synthesis uses what regulation enzyme that resembles the urea cycle?

Answer 21

CPSII

Question 22

Deoxyribonucleotides are synthesized from what?

Answer 22

ribonucleotides

Question 23

Are purines more likely to be degraded or salvaged?

Answer 23

salvaged

Question 24

Purines are broken down to what substance?

Answer 24

uric acid

Question 25

Gout is a problem associated with what pathway?

Answer 25

Purine degradation

Question 26

What can be labeled in order to determine if a patient has gout?

Answer 26

Glycine

Question 27

Orotic aciduria is a problem with 2 defective enzymes that stop the production of what?

Answer 27

UMP

Question 28

When levels of ATP is high, what happens?

Answer 28

GMP is produced

Question 29

When levels of GTP are high, what happens?

Answer 29

AMP is produced

Question 30

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is used in what pathway?

Answer 30

purine salvage pathway

Question 31

PRPP causes an increase in what pathway?

Answer 31

Purine and Pyrimidine synthesis