Question
What are bacterial phages? Describe their structure in detail.
✓
Answer
Viruses which infect and destroy bacteria are called bacteriophages. The word phage is derived from the Greek word ‘phagos’ which means to feeding others. These were discovered separately by Dwart and D'Harrell. Like bacteria, bacteriophages are found in almost every type of habitat and natural conditions. From the point of view of morphology, there are huge difference between them.
Structure of a Bacteriophage : The structure of a typical bacteriophage is similar to that of a tadpole, which is differentiated into a clear head and tail. Most bacteriophages $\left( T _2, T_6\right)$ is head prismatic while its tail is long and cylindrical, the tail remain attached to the prismatic head. With its help they attach to the bacterial cell.
Its length is approximately is equal to the length of the head. The prismatic head is made of protein molecule and its central core contains a large molecule of long DNA. There is a collar between the head and tail. At the proximal end of the tail there is a hexagonal plate attached to the collar, which is called the base plate. Six tail fibers are attached to the lower surface of the base plate with the help of which the phage remains stuck to the surface of the bacteria and the enzymes secreted by them hefp in fusion (lysis) with the bacterial wall.
Structure of a Bacteriophage : The structure of a typical bacteriophage is similar to that of a tadpole, which is differentiated into a clear head and tail. Most bacteriophages $\left( T _2, T_6\right)$ is head prismatic while its tail is long and cylindrical, the tail remain attached to the prismatic head. With its help they attach to the bacterial cell.
Its length is approximately is equal to the length of the head. The prismatic head is made of protein molecule and its central core contains a large molecule of long DNA. There is a collar between the head and tail. At the proximal end of the tail there is a hexagonal plate attached to the collar, which is called the base plate. Six tail fibers are attached to the lower surface of the base plate with the help of which the phage remains stuck to the surface of the bacteria and the enzymes secreted by them hefp in fusion (lysis) with the bacterial wall.
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