Penicillin belongs to the antibiotics known as β‑lactams, and all of them act on bacteria in the same way. Describe how penicillin kills non-resistant bacteria.
One way that a bacterium can be resistant to an antibiotic, such as a β‑lactam, is by possessing protein pumps in its cell surface membrane that remove the antibiotic from the bacterium. The gene for such an efflux pump is located on a plasmid. Outline how the bacterium makes an efflux pump from a gene on a plasmid.
Using Table 2.1, suggest why the MICs of mutant strains 1 and 2 are different from that of strain R.\n\nmutant strain 1\n\nmutant strain 2
Suggest how a population of strain R of $P.\ aeruginosa$ could be replaced by mutant strain 2.
Explain how mutant S could replace a population of strain R of $P.\ aeruginosa$.