Function
Is responsible for the final step in the biosynthesis of archaeosine, a modified nucleoside present in the dihydrouridine loop (D-loop) of archaeal tRNA (PubMed:28383498, PubMed:22032275). Catalyzes the conversion of 7-cyano-7-deazaguanine (preQ0)-modified tRNA to archaeosine-tRNA, transforming a nitrile group to a formamidine group. Can use neither glutamine nor asparagine as amino donor in vitro, is only able to utilize free ammonium (PubMed:28383498). However, the enzyme might function in vivo with a partner that serves to generate ammonium.