Question

1. COVID-19 disease has spread globally, and there is demand for vaccine development. If you are supported by the funding and experts, how will you design a nucleic acid/protein based vaccine or treatment for the disease?

2. Describe and differentiate the conjugation, transformation, and transduction processes that allow genes to be horizontally transferred.

Answer 1

1. Vaccines can be made by many ways but most prominently Live attenuated , Inactivated and Subunit vaccines are used . Recent studies shows that there is recurrence of infection even after complete recovery with no symptoms. So if there is possibility of recurrence ,we need more effective response and long term immunological memory.

Live attenuated vaccine production would be my first choice as it activates immune system very effectively leads to an strong immune response. Once memory generated by this vaccine can protect recepient for lifetime. Again mortality rate for the COVID-19 is less as compared to other severe infections such as Swine Flu. Which opens platform for this vaccine . This vaccine does not need a booster dose . Attenuation by blind passaging in different cells types leads to an attenuation by adapting new environment. Although passaging requires more time , with the help of expert it can be make least. Live attenuated vaccine with treatment will be the best option .

2. These are the type of horizhontal gene transfer , that means passing a DNA to other cell of the same generation. Such gene transfer occurs in bacteria.

Conjugation - In this process , the genetic material is transferred to other cell by means of sex pili. Pili are type of bacterial appendages which is thinner and shorter than flagella. These pili works as a conjugation bridge between two bcaterial cells and through its hollow bridge genetic material transferred. In most cases , DNA is in the form of a plasmid . Such plasmids are called as a F (fertility factor) plasmids. The cell contain F plasmid is called as F+ while other with no plasmid F-. After transfer of DNA recipient F- cell becomes F+ . As one strand of DNA is transferred , other strand is started to synthesize making them double stranded.

Transformation- It is the process in whcih DNA is takes up by the bacterium from its environment. When bacterial cell lyse releases their genetic material into the environment , which is took up by the other bacterium.

Transduction- In this process Viruses that infect bacteria carries short pieces of DNA from one bacteria to other . Such viruses are called as bacteriophage. Such phages requires a host for its replication. They infect the bacteria , uses host machinery , multiplies and releases by lysis of host cell . This is called as lytic cycle. But some phages induces lysogenic cycle which leads to an multipication of phages into the cell without affecting the host for long time. When such lysogenic phages reinfect the new host the will be accidently get transferred .

Difference

Sr. no	Conjugation	Transformation	Transduction
1.	Transfer of DNA by means of pili.	Transfer of DNA by means of uptake from surroundings.	Transfer of DNA by by using vectors.
2.	This process is resistant toDNase as DNA present inside  the bacteria.	This process is sensitive to DNase.	This process is resistant to DNase as naked DNA is  present.
3.	Required physical contact between donor and receipent bacterial cell.	Dose not requires any physical contact.	Involves virus and bacteria but does not reuires any physical contact.