Antibiotics

Question 1

What do sulphonamides inhibit?

Answer 1

Dihydropterate synthase (part of nucleic acid synthesis)

Question 2

What does Trimethoprim inhibit?

Answer 2

Dihydrofolate reductase

Question 3

What do fluoroquinolones inhibit?

Answer 3

DNA gyrase

Question 4

What does Rifamycin inhibit?

Answer 4

RNA polymerase

Question 5

What do macrolides inhibit?

Answer 5

Ribosomes

Question 6

What does chloramphenicol inhibit?

Answer 6

Ribosomes

Question 7

What do tetracyclines inhibit?

Answer 7

Ribosomes

Question 8

What do aminoglycosides inhibit?

Answer 8

Ribosomes

Question 9

Give an example of a fluoroquinolone

Answer 9

Ciprofloxacin

Question 10

Give an example of combination treatment

Answer 10

Co-trimoxazole; combo of sulphonamide and trimethoprim

Question 11

Give an example of a macrolide

Answer 11

Erythromycin

Question 12

Give an example of an aminoglycoside

Answer 12

Gentamycin

Question 13

Which class of antibiotics does erythromycin come under?

Answer 13

Macrolide

Question 14

Which class of antibiotics does gentamycin come under?

Answer 14

Aminoglycosides

Question 15

Which class of antibiotics does Ciprofloxacin come under?

Answer 15

Fluoroquinolones

Question 16

What inhibits RNA polymerase?

Answer 16

Rifamycin

Question 17

What inhibits DNA gyrase? Give an example

Answer 17

Fluoroquinolones e.g. ciprofloxacin

Question 18

What else do fluoroquinolones inhibit?

Answer 18

Topoisomerase 4

Question 19

What is rifamycin used for and what does it inhibit?

Answer 19

RNA polymerase; used for TB

Question 20

What inhibits peptidoglycan synthesis?

Answer 20

Glycopeptides

Question 21

What transports peptidoglycan across the cell membrane?

Answer 21

Bactoprenol

Question 22

What inhibits bactoprenol?

Answer 22

Bacitracin

Question 23

What inhibits transpeptidase?

Answer 23

Beta lactam antibiotics

Question 24

Name 3 beta lactam antibiotics

Answer 24

Carbapenems
Cephalosporins
Penicillin

Question 25

How do beta lactams bind to transpeptidase?

Answer 25

They bind covalently to transpeptidase

Question 26

Name an antibiotic that disrupts the cell wall of gram positive bacteria

Answer 26

Lipopeptides

Question 27

Give an example of an antibiotic which disrupts Gram negative cell membranes and state how they work

Answer 27

Polymyxins - bind to LPS

Question 28

Name four causes of antibiotic resistance

Answer 28

Over-prescription Lack of regulation Livestock forming Lack of development of new antibiotics

Question 29

List the five types of resistance

Answer 29

``` Destruction enzymes Additional targets Hyperproduction of target enzyme Changes to target Alteration in drug permeation ```

Question 30

Give an examples of hyperproduction of the target enzymes

Answer 30

Trimethoprim - increased DHF reductase production by E.coli

Question 31

Give examples of additional targets being produced by bacteria

Answer 31

Different DHF reductase production by E.coli

Question 32

Give examples of destruction enzymes being produced by bacteria

Answer 32

Beta lactamases - hydrolyse the C-N bond of the beta lactam ring

Question 33

Give examples of changes to target enzymes and a bacterium which does this

Answer 33

Changes to DNA gyrase e.g. Staph aureus has a mutation in its topoisomerase enzyme at the Par C region and is therefore resistant to quinolones

Question 34

Give an example of alterations to drug permeation

Answer 34

Increased efflux mechanisms | Decreased aquaporins

Question 35

Which group of bacteria have developed resistance via altering drug permeation?

Answer 35

Gram negative bacteria

Question 36

What are the two types of drugs used to treat fungal infections?

Answer 36

Azoles | Polyenes

Question 37

How do azoles work?

Answer 37

They inhibit the enzymes involved in membrane ergosterol synthesis

Question 38

Give an example of an azole

Answer 38

Fluconazole

Question 39

How do polyenes work?

Answer 39

They bind to ergosterol and create pores

Question 40

Give an example of a polyene

Answer 40

Amphotericin