Polynucleotide Ligase-Catalyzed Joining of Deoxyribo-oligonucleotides on Ribopolynucleotide Templates and of Ribo-oligonucleotides on Deoxyribopolynucleotide Templates

T4 polynucleotide ligase efficiently catalyzes the head-to-tail joining of the ribo-oligoadenylates, r-(pA) 8 and r-(pA) 10 , in the presence of high molecular weight deoxypolythymidylate. The enzyme also catalyzes the joining of deoxy-oligothymidylates, e.g., d-(pT) 10 , in the presence of ribopolyadenylate. The enzyme failed to bring about the joining of r-(pA) 10 when poly r-U was used as the template, although a slow formation of the expected activated intermediate from r-(pA) 10 was detected.