Bacterial strategies to evade natural or human-imposed antibiotics are varied an

Question

Bacterial strategies to evade natural or human-imposed antibiotics are varied and include membrane-bound efflux pumps that export antibiotics from the cell.
A review of efflux pumps (Grkovic, S., et al., 2002) states that, because energy is required to drive the pumps, activating them in the absence of the antibiotic has a selective disadvantage. The review also states that a given antibiotic may play a role in the regulation of efflux by interacting with either an activator protein or a repressor protein, depending on the system involved.

Based on this information, how might such systems be categorized in terms of regulation?

Select all types of regulation that are consistent with the information provided.

negative inducible

negative repressible

positive inducible

positive repressible

negative inducible

negative repressible

positive inducible

positive repressible

Explanation / Answer

Since it is stated that activating efflux pumps in the absence of the antibiotic has a selective disadvantage, therefore it is beneficial for the organism to have inducible pumps so that they are activated only when a stimulus is provided.

Types of regulation that are consistent with the information provided are: positive inducible and negative repressible.

If antibiotic interacts with an activator then it positively induces the pump to start functioning and export the antibiotic out of the cell. If antibiotic interacts with a repressor then the pump will not work, thus negatively repressing its activity and antibiotic is not exported out of the cell in this case.

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.