How Bacteria Become Resistant to Antibiotics

Bacteria are responsible for illnesses such as gonorrhea, tuberculosis, cholera, syphilis, ear infections and other bacterial infections in the body. To kill bacteria doctors prescribe antibiotics that stop bacteria in their tracks. However, like the proverbial germ bacteria are hard to get rid of, especially as they are becoming resistant to the antibiotics that used to be able to kill them.

Antibiotics are compounds that kill bacteria in two ways: (1) antibiotics kill bacteria directly in a method known as bactericidal and (2) antibiotics kill bacteria by preventing them from growing and reproducing in a method known as bacteriostatic. Antibiotics achieve these methods in many ways. Antibiotics kill bacteria by blocking DNA and RNA synthesis, disrupting metabolic processes that bacteria thrive on, interfering with bacterial protein synthesis or by crippling the cell wall of bacteria.

Now, bacteria become resistant to antibiotics by preventing antibiotics from doing their jobs. Bacteria do this in many ways. Bacteria are becoming resistant to antibiotics because they prevent antibiotics from crippling their cell walls. Bacteria have found out that antibiotics attack their cells and destroy them by entering through a crippled cell wall. As a result, bacteria have developed stronger cell walls. In instances where antibiotics do happen to breach the cell walls of bacteria, those bacteria have learned to use energy from ATP to shoot antibiotics from their cells.

Bacteria have also learned to become resistant to antibiotics by changing the shape of their cells, so that antibiotics can't find what it is they are targeting to kill. In a more offensive move, bacteria have become resistant to antibiotics by targeting, attacking and killing antibiotics.

But How Did Bacteria Get So Smart?

As specific antibiotics are developed to kill specific bacteria, bacteria being living organisms have adopted Darwin's idea of survival of the fittest. Bacteria have figured out that in order to survive they must take on new DNA that will make the specific antibiotic designed to kill them ineffective. Bacteria take on new DNA through transformation (bacterial sex), by scavenging for DNA remnants from dead bacteria, by taking on an extra chromosome and by picking up bacterial genes that jump form molecule to molecule.

But bacteria's ingenuity did not happen overnight or on its own. The survival-of-the-fittest stand taken by bacteria has much to do with how people use antibiotics over a prolonged period of time. The use of antibiotics in animal food production and agriculture and the commonplace abuse of antibiotics have contributed to the rise in bacterial antibiotic resistance. When we use antibiotics to prevent illness in animals food production and agriculture, and when we use antibiotics to treat viral infections such and colds and flu we help bacteria to resist antibiotics.