Bacteria that are not easily killed by antibiotics
The evolution of strains of bacteria that are not affected by a particular antibiotic as a result of natural selection.
Single-celled organism. Has a cell wall, cell membrane, cytoplasm. Its DNA is loosely-coiled in the cytoplasm and there is no distinct nucleus
The different stages in development of a new medicine are shown in the interactive timeline below.
Bacteria are responsible for many diseases, you can learn more about diseases caused by bacteria in the Infectious Diseases resource.
New medicines are needed to treat bacterial infections. Bacteria frequently mutate and as a result infections due to strains of antibiotic-resistant bacteria have appeared which can be very difficult to treat. You can see how resistant bacteria can arise in the animation below.