Antifungal Drugs

Question 1

Mechanisms of action & resistance to fluconazole

Answer 1

the role of fluconazole is to inhibit the 14 alpha - demethylase
this stops the biosynthesis of the steroid component of the bacterial cell wall
HOWEVER if this bug is resistance to this it uses efflux pumps to actively pump the drug out of the cell which stops it being able to inhibit its target enzyme

Question 2

what is ergosterol

Answer 2

this is the component which makes up the cell wall in fungal cell walls but not normal cell walls so this is the target for many drugs

Question 3

fungistatic

Answer 3

those that inhibit Fungal growth

Question 4

fungicidal

Answer 4

drugs kill fungal pathogens

Question 5

Mechanisms by which microbial cells might develop resistance

Answer 5

1, The target enzyme is overproduced, so that the drug does not inhibit the biochemical reaction completely.
2, The drug target is altered so that the drug cannot bind to the target. 3, The drug is pumped out by an efflux pump.
4, The entry of the drug is prevented at the cell membrane/cell wall level. 5, The cell has a bypass pathway that compensates for the loss-of-function inhibition due to the drug activity.
6, Some fungal “enzymes” that convert an inactive drug to its active form are inhibited. 7, The cell secretes some enzymes to the extracellular medium, which degrade the drug.