tRNA wybutosine-synthesizing protein 5 (Tyw5)

TRNA hydroxylase that acts as a part of the wybutosine biosynthesis pathway. Wybutosine is a hyper modified guanosine with a tricyclic base located at the 3'-place adjacent to the anticodon of eukaryotic phenylalanine tRNA.

Catalyzes the hydroxylation of 7-(a-amino-a-carboxypropyl)wyosine (yW-72) into undermodified hydroxywybutosine (OHyW*). OHyW* being further transformed into hydroxywybutosine (OHyW) by LCMT2/TYW4.