ExoClone™ PCR Cloning Kit provides a process for cloning any PCR product up to 6kb into any vector with an EcoRI site in its MCS. This process circumvents the problem of sporadic 3′-terminal dA addition during PCR. The ExoClone kit takes advantage of the fact that phosphorothioate linkages are resistant to exonuclease III cleavage. Primers are designed to begin with an extra 5′-AATTC sequence. After amplification with a special dNTP mix (dATP, dCTP, TTP, and thio-dGTP), the product is treated briefly with exonuclease III, and degradation stops when the enzyme encounters the 3′-dG-phosphorothioate. Whether or not a 3′-dA has been added, this treatment produces a 5′-terminal 4-base overhang identical to an EcoRI digestion product. This sticky end allows the ligation of the PCR product into any vector containing an EcoRI site.

• Greater ligation efficiency than blunt-end or TA cloning
• Ligate PCR products (up to 6 kb) into any EcoR I site
• No pre-cut cloning vectors to purchase

ExoClone is a trademark of Sigma-Aldrich Co. LLC