Which one of the following antibiotics binds sterols and alters membrane permeability?
**Core Concept**
The question is testing the student's knowledge of the mechanism of action of certain antibiotics, specifically those that bind to sterols and alter membrane permeability. This is a key concept in pharmacology, as it affects the way these antibiotics interact with cells and exert their effects.
**Why the Correct Answer is Right**
The correct answer binds to sterols, specifically ergosterol, which is a critical component of fungal cell membranes. This binding alters the fluidity and permeability of the membrane, ultimately leading to cell death. This mechanism is particularly effective against fungal pathogens, making it a valuable therapeutic strategy.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not bind to sterols and alter membrane permeability. Instead, it targets other cellular processes, such as protein synthesis or DNA replication.
**Option B:** This option is also incorrect because it does not exhibit the same mechanism of action as the correct answer. It may target other cellular components or pathways, but not sterols or membrane permeability.
**Option C:** This option is incorrect because it is a mechanism of action that is not relevant to the question. It may be a characteristic of other antibiotics, but not those that bind to sterols and alter membrane permeability.
**Clinical Pearl / High-Yield Fact**
One key takeaway from this question is that antibiotics that bind to sterols and alter membrane permeability are effective against fungal pathogens, but may not be effective against bacterial pathogens. This is an important consideration when selecting antibiotics for treatment.
**Correct Answer:** C. Polyenes.