In Vitro Packing of Vector: Lamda Phage

Production of infectious Lamda phage virus particles from a naked DNA with Cos sites, preheads, tails, and packing proteins in the laboratory conditions.
Like a wild-type virus, an assembled virus can infect the bacterial host, inject its DNA into the host, and form plaques.
BHB2688: lysogenic for CI,, b2 red3 Eam4 Sam7 can accumulate tail and packing proteins but not prehead proteins. Major Capsid geneE is mutated
Unlike BHB2690, which is lysogenic for CIt, B2 red3, Dam15, and Sam7 can synthesise tail and prehead proteins but not packing proteins. DNA Packing protein gene D is mutated
A mixture of the two lysates gives a full set of lambda proteins, which when mixed with lambda DNA, can generate infectious phage particles.
Proteins from both mutant and infected bacteria are isolated, mixed, and then incubated with lamda DNA or Cosmids or lamda based vectors with Cos sites.
Sequentially, all the phage proteins are assembled to form a head and tail structure, and packing proteins D and A will help in the packing of DNA with cos sites which are separated by 38 to 53 kb DNA
The functional assembly of the virus has taken place in laboratory conditions, hence the process is called in vitro packing.
In vitro packing is a very essential technique, and it is part and parcel of genomic DNA library construction by using cosmid vectors or Lamda phage replacement vectors.

[@ankitamalakar8993]

Thank you for explaining it so well.

[@Dr.DNA-Primer]

Welcome and try to subscribe for updates

[@shalink.sharma2190]

Sir, what is single strain system in packaging of lambda cloning vector?

[@Dr.DNA-Primer]

Mutation in Cos sites of Lamda DNA can not undergo replication but can synthesize all phage proteins. Such proteins are purified and mixed with recombinant lamda molecule and then phage particles are formed in vitro. Mutations in Cos sites lambda DNA phage strain is sufficient to pack the recombinant lamda DNA.