Question

After transformation, what will be the fate of DNA from the vector alone ligation reaction?

A. replicated by cellular enzymes

B. degraded by cellular proteases

C. integrated into bacterial chromosome through site specific recombination

D. degraded by RecBCD

E. integrated into bacterial chromosome through homologous recombination

Answer 1

ANS C. integrated into bacterial chromosome through site specific recombination

The final step in the construction of a recombinant plasmid is connecting the insert DNA (gene or fragment of interest) into a compatibly digested vector backbone. This is accomplished by covalently connecting the sugar backbone of the two DNA fragments. This reaction, called ligation, is performed by the T4 DNA ligase enzyme. The DNA ligase catalyzes the formation of covalent phosphodiester linkages, which permanently join the nucleotides together. After ligation, the insert DNA is physically attached to the backbone and the complete plasmid can be transformed into bacterial cells for propagation.

DNA backbone Sticky End DNA insert G DÕO Plage SAUVEDO CO Sticky End Ligation Recombinant DNA XXHENHEVOS