Chapter 20: Antibacterial Drugs continued

Question 1

What do protein synthesis inhibitors do? (2)

Answer 1

• prevent translation
• can have adverse effects on host cells

Question 2

What type of ribosomes do bacteria, eukaryotes, and mitochondria have?

Answer 2

bacteria have 70s
Eukaryotes have 80s (in cytoplasm)
mitochondria have 70s

Question 3

What antibacterial drugs are protein synthesis inhibitors?

Answer 3

1. Chloramphenicol
2. Aminoglycosides
3. Tetracyclines
4. Macroslides

Question 4

What antibacterial drugs are protein synthesis inhibitors? (4)

Answer 4

1. Chloramphenicol
2. Aminoglycosides
3. Tetracyclines
4. Macroslides

Question 5

What are characteristics of chloramphenicol? (4)

Answer 5

• extremely effective
• extremely cheap
• extremely toxic
• occasionally used in eye drops for conjunctivitis

Question 6

in lecture, what does chloramphenicol induce?

Answer 6

• anemia cuz u cant produce RBC

Question 7

In diagram in slide 5, what do macrophages and chloramphenicol do?

Answer 7

• macrophage prevent the continuation of protein synthesis
• chloramphenicol prevents the peptide bonds from being formed

Question 8

Name 4 aminoglycosides.

Answer 8

• streptomycin
• gentamicin
• neomycin
• tobramycin

Question 9

What are aminoglycosides? (3)

Answer 9

• broad spectrum
• useful against gram -
• can be toxic and lead to kidney damage

Question 10

Giv an example of an aminoglycoside and what is causes

Answer 10

• opportunistic Pseudomonas sp.
• causes infections in cystic fibrosis

Question 11

What are tetracyclines? (3)

Answer 11

• broad spectrum
• penetrate host tissues well
• can be used against chlamydia

Question 12

What do tetracyclines suppress? (2)

Answer 12

• can suppress microbiota of intestinal tract
• lead to superinfections

Question 13

Are tetracyclines toxic? (3)

Answer 13

• they can be
• leads to yellowing of teeth in children
• liver damage
  just an fyi, these are always put in brown vials

Question 14

If you are allergic to penicillin, what would doctors give you instead? this was in lecture

Answer 14

tetracyclines

Question 15

What are macroslides? (2)

Answer 15

• narrow spectrum for gram positives
• does not penetrate the outer membrane of most gram negatives

Question 16

When would macroslides be used?

Answer 16

often used for people who are allergic to penicillins

Question 17

What is an example of a macroslide?

Answer 17

erythomycin

Question 18

What two antibacterial drugs are used to injure the plasma membrane?

Answer 18

• polymixin B
• Lipopeptides

Question 19

What is polymixin B? (2)

Answer 19

• bacteriocidal, but toxic
• generally used only in topical treatments
  note that polysporin had this

Question 20

What are lipopeptides? (3)

Answer 20

• narrow spectrum against gram positives
• one of the newest antibiotics
• approved to treat MRSA

Question 21

What two antibacterial drugs inhibit nucleic acid synthesis?

Answer 21

• rifamycins
• Fluoroquinolones

Question 22

What are rifamycins?

Answer 22

• blocks transcription (no mRNA, no protein)
• able to penetrate host tissues well

Question 23

What are rifamycins used to treat? Give examples of drugs

Answer 23

• tuberculosis and leprosy
  ex. rifampin, rifampicin

Question 24

What are fluoroquinolones?

Answer 24

• inhibit bacterial DNA replication (cells cannot divide)
• useful for fighting pathogenic E. coli (gram -) and anthrax (+) (therefore broad spectrum)
  ex. ciprofloxacin

Question 25

What would be a problem with fluoroquinolones?

Answer 25

• resistant bacteriaq develop quickly