Drugs

Question 1

AZT (azidothymidine)

Answer 1

• nucleoside analogue of thymidine
• anti-viral
• no free 3’ OH group = chain termination
• has high affinity for reverse transcriptase
• Treatment for HIV

Question 2

Didanosine (ddl)

Answer 2

• nucleoside analogue of adenosine
• no free 3’ OH group = chain termination
• high affinity for reverse transcriptase
• Treatment for HIV

Question 3

Acyclovir

Answer 3

• nucleoside analogue of guanosine
• has an open chains instead of a closed pentose sugar ring
• no free 3’ OH group
• viral thymidine kinase = 1st phosphorylation
• Treatment for herpes = only attacks infected cells and does not touch healthy cells because it can only be phosphorylated by viral thymidine kinase which is only in infected cells

Question 4

Tenofovir

Answer 4

• nucleotide analogue of adenosine monophosphate
• open chain instead of pentose sugar ring
• no free 3’ OH group = chain termination
• treatment for HIV infections

Question 5

Cytosine arabinoside (araC) aka cytarabine

Answer 5

• nucleoside analogue of cytosine - anti-cancer
• has 3’OH group, but there is a 2’ OH group too = steric hinderance!
• chain termination
• treatment for leukemia [myeloid + lymphoma]

Question 6

Adenosine Arabinoside (araA) aka vidarabine

Answer 6

• nucleoside analogue of adenosine - anti-caner
• has 3’OH group, but there is a 2’ OH group too = steric hinderance!
• chain termination
• treatment for anti-neoplastic agent, relapsed childhood acute lymphoblastic leukemia and herpes simplex infections

Question 7

Decitabine

Answer 7

• nucleoside analogue of cytidine - hypomethylation agent
• removes a methyl group
• prevent DNA methyltransferase enzymes from methylating cytosine - remember because DNA methylation is an important mechanism of gene regulation euk.
• important for transcriptional regulation
• use as a anti-methylator to counteract cancer cells

Question 8

azacytidine

Answer 8

• nucleoside analogue of cytidine - hypomethylation agent
• removes a methyl group
• prevent DNA methyltransferase enzymes from methylating cytosine - remember because DNA methylation is an important mechanism of gene regulation euk.
• important for transcriptional regulation
• use as a anti-methylator to counteract cancer cells

Question 9

Ciprofloxacin (Quinolone type)

Answer 9

• inhibits topoisomerase II (bacterial DNA gyrase)
• positive supercoils are not unwound
• treatment of respiratory and urinary tract infections and can also be used to treat anthrax

Question 10

Camptothecin

Answer 10

• anti-cancer drug
• binds to and inhibits topoisomerase I = DNA breakage
• inhibits replication

Question 11

Etoposide

Answer 11

• anti-cancer drug
• inhibits the activity of topoisomerase II (DNA gyrase) = DNA breakage
• inhibits replication

Question 12

Actinomycin D (Dactinomycin)

Answer 12

• binds between G-C bases
• inhibits replication by prevent ssDNA and inhibiting RNA transcription
• anti-cancer drug, not normally used as an antibiotic

Question 13

Rifampin

Answer 13

• Antibiotic
• from a strain of streptomycin
• inhibits transcription initiation by blocking the formation of the 1st phosphodiester bond
• RNA polymerase is not affected
• treatment for tuberculosis

Question 14

Amanita Phalloides

Answer 14

-produces alpha amanitin which inhibits RNA polymerase II (mRNA)

Question 15

Novobiocin

Answer 15

• inihibits topoisomerase II (DNA gyrase)

- positive supercoils are not unwound

Question 16

What do Rotenone
piericidine A (bacterial antibiotic)
barbiturate amytal
do?

Answer 16

Inhibit NADH dehydrogenase in Complex I

Question 17

What do CO
Azide
Hydrogen Sulphide (H2S)
Cyanide (CN-)
do?

Answer 17

Inhibit cytochrome oxidase (Complex IV)

Question 18

what does Antimycin A (antibiotic) do?

Answer 18

Inhibits cytochrome b of cytochrome reductase (Complex III)

Question 19

what does Oligomycin (Streptomyces antibiotic) do?

Answer 19

Inhibits ATP synthase (Complex V)

Question 20

what do ETC inhibitors do?

Answer 20

decrease ATP synthesis, decrease ETC and oxygen consumption

Question 21

what does Atractyloside
Bongkrekic Acid
do?

Answer 21

Inhibits ADP/ATP transport; inhibits function of nucleotide translocase

Question 22

what do DNP (dinitrophenol)
ASA (aspirin)
Thermogenin
Ionophores
do?

Answer 22

Destroy the protein gradient

Question 23

what do Ionophores
• Gramicidin = channel formers
• Valinomycin = mobile carrier
do?

Answer 23

Make inner mitochondrial membrane permeable to compounds that can’t usually cross (small molecules now can get through)

Question 24

what do uncouplers do?

Answer 24

decrease ATP synthesis, increase ETC, increase oxygen consumption

Question 25

what do uncouplers and ionophores do?

Answer 25

allow for dissipation of the proton gradient

Question 26

Streptomycin

Answer 26

Family of antibiotics with aminoglycoside structure | Prevents assembly of ribosome by binding to 30S subunit

Question 27

Tetracycline

Answer 27

Family of antibiotics with four (tetra) ring (cyclic) structure Blocks elongation by binding to 30S subunit and blocking the access of the aminoacyl-tRNA access to the A-site on the mRNA-ribosomal complex

Question 28

Erythromycin (clindamycin)

Answer 28

Family of antibiotics and has macrolide structure | Binds to the 50S subunit of the complete 70S ribosome of bacteria and blocks ribosome translocation

Question 29

Chloramphenicol

Answer 29

nhibits peptidyl transferase activity May inhibit mitochondrial translation Not broadly used because potential to develop decrease WBC Important in some cases – some meningitis conditions

Question 30

Cycloheximide

Answer 30

``` Inhibits peptidyl transferase activity May inhibit mitochondrial translation Toxic to eukaryotes Prokaryotes and mitochondria not affected Important experimental tool (cheap) ```

Question 31

Puromycin

Answer 31

Analog of aminoacyl-tRNA Toxic to both prokaryotes and eukaryotes translation It’s a chain terminator in protein synthesis

Question 32

Diphtheria toxin

Answer 32

C. diphtheria + bacterial virus Causes diphtheria – lethal disease of respiratory tract The A fragment of the toxin catalyzes the ADP-ribosylation of EF-2 = inhibiting translocation in eukaryotes