has part archaeosine-tRNA biosynthetic process https://github.com/geneontology/go-ontology/issues/27059 Archaeosine (7-formamidino-7-deazaguanosine) is a structural variant of the hypermodified nucleoside 7-deazaguanosine. The biosynthesis pathway starts with archaeosine tRNA-guanine transglycosylase (ArcTGT) which catalyzes the exchange of guanine at position 15 in the D-loop of archaeal tRNAs with a free 7-cyano-7-deazaguanine. hjd The chemical reactions and pathways involved in the biosynthesis of archaeosine, an archaea-specific modified base found at position 15 in the D-loop of certain archaeal tRNAs. biological_process GO:0002927 2012-01-18T03:06:27Z archaeosine synthase activity tRNA modification 7-cyano-7-deazaguanine tRNA-ribosyltransferase activity