Viollet S, Fuchs RT, Munafo DB, Zhuang F, Robb GB.

BMC Biotechnol. 2011 Jul 1;11:72. doi: 10.1186/1472-6750-11-72.

T4 RNA Ligase 2 truncated active site mutants: improved tools for RNA analysis

The K227Q mutation prevents transfer of the adenylyl residue from the adapter to unwanted targets.