Reaction: 2'-phospho-[ligated tRNA] + NAD+ = mature tRNA + ADP-ribose 1",2"-phosphate + nicotinamide
For diagram click here and for mechanism, click here.
Glossary: ADP-ribose = adenosine 5'-(5-deoxy-D-ribofuranos-5-yl diphosphate)
Other name(s): yeast 2'-phosphotransferase; Tpt1; Tpt1p; 2'-phospho-tRNA:NAD+ phosphotransferase
Systematic name: 2'-phospho-[ligated tRNA]:NAD+ phosphotransferase
Comments: Catalyses the final step of tRNA splicing in the yeast Saccharomyces cerevisiae . The reaction takes place in two steps: in the first step, the 2'-phosphate on the RNA substrate is ADP-ribosylated, causing the relase of nicotinamide and the formation of the reaction intermediate, ADP-ribosylated tRNA . In the second step, dephosphorylated (mature) tRNA is formed along with ADP ribose 1",2"-cyclic phosphate. Highly specific for oligonucleotide substrates bearing an internal 2'-phosphate. Oligonucleotides with only a terminal 5'- or 3'-phosphate are not substrates .
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 126905-00-8
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