splicing, is currently the most commonly used fusion splicing technology. It is more expensive for its complex technology, more powerful and flexible, and less sensitive to variations in the cable and environment.
DNA ligase is similar to the construction crew that builds the bridges. Through the process of DNA replication, many fragments are produced. DNA ligase fills the spaces between the different fragments to bridge together the gaps in DNA. It accomplishes this by creating phosphodiester bonds between the 3' end of one nucleotide and the 5' end of the next nucleotide.
Cutting and Splicing DNA Molecules. If you want to insert a piece of new DNA (foreign DNA) into an existing strand you'd have to cut the existing strand, somehow position the foreign DNA, and then join the strands. This joining is called ligation and can be done with the enzyme DNA ligase. Restriction enzymes are produced by bacteria and function to protect bacteria from foreign DNA (like viruses). Restriction enzymes work by degrading foreign DNA. Restriction enzymes recognize and cut the sugar phosphate backbone of the DNA molecule at specific sites on a strand of DNA. The restriction enzyme recognition site is determined by a specific sequence of nucleotides. Thousands of restriction enzymes have been isolated, although many share the same recognition sequence.