The twelfth motif instance identified by searching the kink-turn motif using RNAMotifScanX. (A) The base-interaction pattern and the 3D structure of this motif instance. Color labels: green—the NC helix where the cross-strand A–A stacking is found; red—the bulge loop that corresponds to the kink region of the motif instance; blue—the C helix where two A-minor interactions are found (a type I and a type II A-minor interaction); purple—the adenine residues that participate in the two A-minor interactions. (B) Superimposition of the C helices of a kink-turn (blue), a reverse kink-turn (red), and this motif instance (orange). The NC-helix turns toward neither left nor right, but to the opposite direction. (C) Interacting residues (highlighted in orange) of this motif with the ribosomal proteins L30P (1S72, chain W) and L32E (1S72, chain Y).
