Bacteriophages, also called phages, are viruses that have the ability to infect bacteria.s, which are used for the viral replication process. The term comes from the Greek and means «bacteria eater. Like all other viruses, bacteriophages are cellless and obligate intracellular parasitessince they do not have their own metabolism and need the host cell to reproduce.
Bacteriophages are found in different places in nature and are not responsible for causing harm to human health. By parasitizing bacteria, bacteriophages act in these places, controlling bacterial populations.
→ Characteristics of bacteriophages
Most bacteriophages have DNA as their genetic material, but there are types that have RNA. Bacteriophages with DNA generally have the following components: head, tail and tail fibers. The head is where the genetic material is, and the tail and the tail fibers are related to the penetration of the genetic material into the host cell. Bacteriophages can infect different bacteria, but there are very specific types that are able to infect only a certain type of bacteria.
Note the main parts of a bacteriophage
→ Bacteriophage infection cycle
Upon finding the host cell, the bacteriophage attaches to it. The virus injects its genetic material inside the bacterium and begins to use its structures in order to duplicate it and produce new capsids. Utilizing the bacterial machinery, the bacteriophage is able to produce new viruses.
Don’t stop now… There’s more after the publicity 😉
Bacteriophages may or may not cause lysis (disruption) of the host cell. Bacteriophages that promote lysis are called lytics, and those that do not cause cell death are called tempered or lysogenic. Temperate bacteriophages cause their genetic material to be incorporated into the cell’s genome and, as the bacterium divides, they transmit the viral material to their offspring. In this case, viruses assume a state of latency. From time to time, however, the lysogenic cycle can be interrupted and the lytic cycle begins, which causes the release of bacteriophages and cell lysis.
ASome types of bacteriophages take 20 to 60 minutes to complete their multiplication.
→ phage therapy
Bacteriophages, in addition to not causing harm to our health, can be used to treat diseases caused by bacteria. This technique is based on insertion of bacteriophages into the organism so that they find, parasitize the bacteria that cause the disease and promote their destruction (lysis). The main advantage of phagotherapy is that bacteriophages act only on bacteria, replicating only inside these cells.
Curiosity: Did you know that bacteriophages are probably the most abundant life form on the planet?
By Ma. Vanessa dos Santos