cl19470

RNA 2'-phosphotransferase, Tpt1 / KptA family; Tpt1 catalyses the last step of tRNA splicing in yeast. It transfers the splice junction 2'-phosphate from ligated tRNA to NAD, to produce ADP-ribose 1"-2"-cyclic phosphate. This is presumed to be followed by a transesterification step to release the RNA. The first step of this reaction is similar to that catalysed by some bacterial toxins. #=GF CC Escherichia coli KptA and mouse Tpt1 are likely to use the same reaction mechanism.