Question

What do you mean by disarmed pathogen and what is its importance?

Answer 1

Hint: A pathogen is described as an organism that causes the disease to its host, with the severity of the disease symptoms known as toxicity. Pathogens include bacteria and viruses as well as multicellular and unicellular eukaryotes. An infectious agent or disarmed pathogen is a biological agent that causes illness or disease to its host.

Complete step-by-step answer:
Disarmed pathogens are produced by eliminating genes that are responsible for virulence and adding genes of our interest instead so that when the disarmed pathogen is used to contaminate the host, it does not cause disease but transmits recombinant DNA into the host. Disarmed pathogens such as phage viruses,Agrobacterium tumefaciens are also used in the transmission of r-DNA into the host. Agrobacterium tumefaciens is a bacterium that is a pathogen of various dicot plants. It includes a plasmid known as Tumour inducing (Ti) plasmid. This bacterium naturally delivers a piece of Ti plasmid DNA known as a ‘T-DNA’ to the host. This results in the transformation of normal plant cells into tumour cells to generate chemicals that are needed by the bacterial pathogen. This Ti plasmid has now been transformed into a cloning vector that is no more pathogenic to the plants but still able to deliver genes of our interest into a wide range of plants. Retroviruses transmitted between normal animal cells and cancerous cells. Retroviruses have also been disarmed and are now utilised to carry suitable genes into animal cells. Bacteriophages are viruses that contaminate bacteria. They are very much host specific and cannot be utilised as disarmed pathogens in animals. Plasmids are double-stranded, circular, extrachromosomal DNA molecules present in bacteria.

Note: Pathogens are those organisms that cause diseases. Disarmed pathogen vectors when permitted to infect the cell, transmit the recombinant DNA into the host.