Bacteriophage
A bacteriophage is a virus that infects bacteria. It consists of genetic material (DNA or RNA) surrounded by a protein coat. Bacteriophages attach to the surface of a bacterium, inject their genetic material, and use the bacterial cell to reproduce new viral particles. After this, the bacterial cell often breaks down (lysis), releasing new bacteriophages.
Did you know that...
01
Up to 500 new particles
One phage can produce up to 500 new viral particles in a single infected bacterial cell.
02
About 165 million years
Phages have existed on Earth for about 165 million years, making them some of the oldest known pathogens.
03
70%
70% of all bacteria in the ocean can be infected by phages.
04
50%
Phages can reduce bacterial populations by 50% in a few hours.
05
About 100 years
They have been used in medicine for about 100 years.
Structure and functions of microorganisms
Head (Capsid)
Contains the nucleic acid (DNA or RNA) of the phage. The capsid protects the genetic material of the virus until it is introduced into the bacterial cell. The shape of the head can be icosahedral or filamentous.
Nucleic Acid
The genetic material of the phage, which may be single-stranded or double-stranded DNA or RNA. Contains all the necessary information for the synthesis of new phage particles inside the bacterial cell.
Neck
Connects the head to the tail in some types of bacteriophages, such as contractile type phages. The neck may contain molecules necessary for attachment to the bacterial cell.
Tail
Serves to attach to the bacterial cell and introduce the phage's nucleic acid inside it. The tail may be equipped with specific fibers that recognize and bind to receptors on the surface of the bacterium.
Basal Body
Located at the end of the tail and participates in the process of attaching to the bacterial cell, as well as in the injection of viral DNA or RNA through the bacterial cell wall.
Tail Fibers
Help the phage precisely latch onto specific receptors on the surface of the bacterial cell, ensuring the specificity of the infection.
