What is the significance of adding proteases at the time of isolation of genetic material (DNA)?
Proteases degrade the proteins present inside a cell (from which DNA is being isolated). If the proteins are not removed from DNA preparation then they could interfere with any downstream treatment of DNA.
While doing a PCR, 'denaturation' step is missed. What will be its effect on the process?
If denaturation of double-stranded DNA does not take place then primers will not be able to anneal (joining) to the template. Hence, no extension will take place and after are there will be no amplification.
Name a recombinant vaccine that is currently being used in vaccination program.
Hepatitis-B recombinant vaccine (engerix) is used for vaccination of hapatitis virus.
Do biomolecules (DNA and protein) exhibit biological activity in anhydrous conditions?
Biomolecules (DNA, and protein) exhibit change in biological activity in anhydrous conditions, In non-aqueous or anhydrous conditions the rigidity of protein and DNA increases due to the weakening of hydrogen bond strength.
It results into the change in overall free energy, which is the combined effects of the exposure of the interior polar and non-polar groups and their interaction with water. In absence of aqueous condition, the free energy change is negative, which is responsible for the denaturation of biomolecules.
Increasing strength of hydrogen-bond causes water to primarily bond with itself and not to be available for the hydrating structure of proteins or DNA, or for dissolving ions.
On the other hand, if the water-water hydrogen bond strength reduces then the exchange mechanisms operating within the cell, such as hydrogen bonded water chains within and between proteins and DNA, will become non-operational. It will further leads to the denaturation.
What modification is done on the Ti-plasmid of Agrobacterium tumefaciens to convert it into a cloning vector?
The plasmid is disarmed by deleting the tumour inducing genes in the plasmid. So, that it become an effective cloning vector. The modified tumour inducing (Ti) plasmid of Agrobacterium tumefaciens will no longer remain pathogenic to the plants but still deliver genes of interest into a variety of plants.