label: 18S rRNA aminocarboxypropyltransferase activity
label_lc: 18s rrna aminocarboxypropyltransferase activity
description: "Catalysis of the reaction: N1-methylpseudouridine in 18S rRNA + S-adenosyl-L-methionine = H+ + N1-methyl-N3-[(3S)-3-amino-3-carboxypropyl]pseudouridine in 18S rRNA + S-methyl-5'-thioadenosine."