BioWiki

Table of Contents

<select Language> bio:リガーゼ|Japanese bio:en:ligase|English </select>

Ligase

Ligase connect a 5'-terminus and 3'-terminus of a polynucleotide with ATP. This enzyme plays roles in DNA replication and reparing in vivo.


ligase+ATP →

Reactions

DNA replication

  • Connect 5'-terminus and 3'-terminus of 'Okazaki fragments' which is polymerized by a polymerase.

DNA reparing

  • Connect 5'-terminus and 3'-terminus after BER or NER reparing.

Purpose of use

The ligase is an essential enzyme for cloning technology. Restriction enzymes are compared to 'scissors', ligases are compared to 'glue' as well.

About using Ligation-Kits

Commercially available 'ligation-kits' contain specialized buffers optimized with salt concentration and detergent concentration. Moreover, some kits contain additional proteins such as a reparing protein, PprA (Nippon gene). We have to be careful for the buffer before transformation because the buffer might suppress the ligation reaction. Therefore, the solution after ligation reaction should be subjected to Ethanol-precipitation method. Some ligation kit contains a buffer that cancel such adverse effect (TaKaRa). Anyway, we can use kits emphasizing 'High-Efficient' in ease, but we should understand why it is efficient.