L13 Nucleotide metabolism

Question 1

What are the 3 structural components of nucleotides?

Answer 1

Ribose, base and phosphate

Question 2

How many rings does purines have?

Answer 2

2

Question 3

How many rings does purimidines have?

Answer 3

1

Question 4

What are the 2 types of purines?

Answer 4

Adenine and Guanine

Question 5

What are the 4 types of purimidines?

Answer 5

Uracil, Thymine, and Cytosine

Question 6

What is the tranformation flow of nucleic acids to mono-nucleotides?

Answer 6

Nuleic acids → mononucleotides(3 components: ribose, base and phosphate) → phosphate removal to form nucleosides (2 components: ribose and base) → bases (purines and pyrimidines) → go through salvage reactions (recycling of intact bases for inter-conversions) to form mono-nucleotides

Question 7

Can purines be degraded compeletly?

Answer 7

No

Question 8

Uric acid is formed from catabolism of what chemical?

Answer 8

Purine nuleotides

Question 9

Elevated levels of uric acid can cause which kind of disease?

Answer 9

GOUT

Question 10

Allopurinol is a drug for treatment of GOUT, what is it structurally similar to?

Answer 10

Hypoxanthine

Question 11

In what form are nitrogens in pyrimidines released？

Answer 11

NH4+ and then urea

Question 12

Pyrimidine carbon skeletons are degraded to what metabolite?

Answer 12

Acetyl-CoA or succinyl CoA, which can be completely oxidized

Question 13

Inter-convensions of purine nuleotides happens at which level?

Answer 13

Monophosphate level

Question 14

Inter-convension of purimidine nuleotides happens at which level?

Answer 14

Different levels, not just monophosphate level

Question 15

What is the first step of biosynethesis of new purines?

Answer 15

Formation of 5-phosphoriboxyl 1-pyrophosphate (PRPP), which is a sugar
Have a sugar first that act as a platform

Question 16

Which enzyme is anti-cancer drugs target at?

Answer 16

Amidophosphoribosyl transferase