Question

Discuss the lysogeny phase of the bacteriophage multiplication cycle. Briefly explain the medical significance of this cycle.

Answer 1

Lysogenic method is one of the proedure through which phage virus reproduced. During Lysogenic cycle a phage virus inserted its genetic material and get inserted with the genome of the host. Otherqise the viral nucleic acid remains inside the host cytoplasm as circular nucleic acid. The genetic material of phage virus is known as prophage and can passed to subsequent daughter cells through cell division. In normal situation, a phage virus in lysogenic cycle is not harmful to host as its remain in latent stage. However, due to exposures like UV the bacteriophage starts to reproduce by the lytic cycle method, when the viral genetic maerial takes the control over the host replciation machinery and new bacteriohages released by destroying the host cells.

In some instances presence of gene expression of a phage virus of lysogenic cycle can alter the phenotype of the host.which is called as lysogenic conversion.which is of madical concern. If we take the example of the bacteria Corynebacterium diphtheriae, normally do not show any harmful effect to host organism. However, if the bactera get contaminated with phage ? virus infect the bacteria, the bacteria becomes pathogenic and produce toxin responsible for diptheria.