You hear about resistant bacteria more and more in the news. This is often the result of antibiotics use. But what exactly is resistance, and how does it originate?
You hear about resistant bacteria more and more in the news. This is often the result of antibiotics use. But what exactly is resistance, and how does it originate?
Antibiotic resistance
Antibiotic use has increased by 36% in the past 10 years. But no new antibiotic has been discovered since 1987. This has led to excessive and unwise use of antibiotics, resulting in resistance. Bacteria adapt easily and quickly become insensitive to antibiotics. More and more often, they become resistant to almost all types of antibiotics that we have, such as the multi-resistant hospital bacterium MRSA (meticillin-resistant Staphylococcus aureus). Antibiotics kill sensitive bacteria, but leave resistant bacteria untouched. They can then multiply and spread undisturbed. Misuse of antibiotics further accelerates this process, resulting in a vicious cycle.
Adaptability
Bacteria adapt incredibly quickly. First of all, because they multiply very quickly. They do that through binary fission. On average, bacteria divide every 20 minutes. The fastest can do this in just six minutes! In humans it takes an average of 30 years before we produce the next generation. Under the right conditions, therefore, a billion bacteria will originate from one bacterium in just ten hours. So there are a lot of divisions, and with each division there can be small mistakes in the DNA, so-called mutations. Most of these mutations have no effect or are even harmful to the bacterium. But sometimes the bacteria can survive just a little better. For example in an environment with antibiotics. In addition, bacteria also absorb a lot of genetic material from their environment and actively exchange it with each other. This is called conjugation. For example, a bacterium can "borrow" new properties, such as insensitivity to antibiotics, from other bacteria. Recently it has even been discovered that bacteria even actively cooperate against antibiotics and become insensitive.