Younger Nucleotide Metabolism

Question 1

Nucleotide functions:

Answer 1

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)

Question 2

Features of Nucleotides:

Answer 2

Nitrogenous base and sugar

Question 3

Nitrogenous base: Purines and Pyrimidines

Answer 3

CUT PY
Pyrimidines: Cytosine, Thymine (DNA) Uracil (RNA)
AG PU
Purines: Adenine and Guanine

Question 4

Nucleotides sugar:

Answer 4

Ribose in RNA

Deoxyribose in DNA

Question 5

Nucleoside=

Answer 5

Nitrogenous base + Sugar

Question 6

Nucleotide=

Answer 6

Nucleoside + 1-3 phosphate groups

Question 7

Be able to distinguish between ribonucleic acids and deoxyribonucleic acid.

Answer 7

Know that OH is in RNA and H in DNA

Question 8

The ribose 5-phosphate is from what other pathway?

Answer 8

HMP shunt

Question 9

What is the enzyme that catalyzes the formation of the activated pentose?
Activates the ribose by putting inorganic phosphate on it

Answer 9

PRPP synthetase

Question 10

List the + and - regulators of PRPP synthetase

Answer 10

(+) Inorganic phosphate

(-) purine ribonucleotides

Question 11

What carbon is pyrophosphate and nitrogenous base bound to?

Answer 11

1’ Carbon

Question 12

What is the rate limiting step of production of purines, this is catalyzed by what enzyme?

Answer 12

PRPP amidotransferase (puts amine group on base)

Question 13

What is a derivative of Folate?

Answer 13

THF (tetrahydrofolate)

Question 14

Why is folate required in our diet?

Answer 14

We need it to modify it to make THF.

Question 15

As long as you have ______ you are going to be activated and be producing purine (promoting the production of nucleotides).

Answer 15

PRPP Amidotransferase

Question 16

What “drug” will inhibit PRPP amidotransferase?

Answer 16

6-Mercaptopurine

Question 17

What drug is a folic acid, inhibits THF synthesis, and therefore is an anti-tumor drug?

Answer 17

Methotrexate (mammalian cells)

Question 18

What drug is a structural analog of PABA (para aminobenzoic acid)?

Answer 18

Sulfonamides (sulfa drugs) they function as antibiotics

Question 19

Whats the activator of PRPP? (rate limiting, committed step of pyrimidine synthesis)

Answer 19

CPS-II (carbamoyl phosphate synthetase II)

Question 20

What activates and inhibits CPS-II?

Answer 20

(+) PRPP

-) UTP (also downstream products are inhibitors

Question 21

PRPP provides the ________ for the pyrimidine.

Answer 21

pentose

Question 22

Pyrimidine bases are produced then attached to ____.

Answer 22

PRPP

Question 23

What else can hydroxyurea treat other than being an anti-tumor drug?

Answer 23

Sickle Cell Anemia because it promotes HbF synthesis

Question 24

Does synthase need ATP to work?

Answer 24

no, synthetase does

Question 25

What enzyme inhibits the antitumor drug 5-FU?

Answer 25

Thymidylate synthase

Question 26

_________ inhibits THF in bacteria.

Answer 26

Trimethoprim

Question 27

What do sulfa drugs (sulfonamides) do?

Answer 27

They are good at targeting prokaryotes, they target bacteria that make folic acid.

Question 28

________ pathway is more important for purines than pyrimidines.

Answer 28

Salvage

Question 29

Adenosine deaminase deficiency is one of the causes of ________ disease (14% of cases).

Answer 29

SCID (severe combined immunodeficiency disease)

may require living in a bubble

Question 30

What is a treatment of SCID?

Answer 30

Bone marrow transplant or enzyme replacement

Question 31

What enzyme is involved with excretion which produces uric acid and is excreted in urine?

Answer 31

Xanthine oxidase

Question 32

What does xanthine oxidase deficiency do?

Answer 32

It causes accumulation of nitrogenous bases in the body. Because it is not being degraded to uric acid.

Question 33

What happens with Gout?

Answer 33

hyperuricemia (accumulation of uric acid in blood) by over production of uric acid (xanthine oxidase overproduction)

Question 34

What drug inhibits xanthine oxidase which produces uric aced? Slows down production of uric acid.

Answer 34

Allopurinol

Question 35

What disease is a deficiency in the purine salvage pathway, caused by HGPRT, a deficit of purines, resulting in production of uric acid… resulting in extreme hyperuricemia

Answer 35

Lesch-Nyhan syndrome (self mutilation, mental retardation, bad stuff)

Question 36

What is a build up of uric acid called?

Answer 36

hyperuricemia

Question 37

Gout can affect what parts of the eye?

Answer 37

Conjunctiva, cornea, iris, sclera, lens, other eye tissues.