File:7591334f5a.jpg

(A) Best-fit superposition of 38 final simulated annealing structures of the A-site RNA−gentamicin C1a complex, viewed from the major groove side of the RNA. The heavy atoms have been superimposed. The RNA is shown in beige and gentamicin C1a is red. The three rings of gentamicin C1a are numbered as in Figure 1. (B) Single representative structure of A-site RNA−gentamicin C1a complex. All heavy atoms are displayed. The same colors as in (A) are used except that RNA phosphate groups are highlighted. (C) Best-fit superposition of gentamicin C1a of the 38 final structures of the A-site RNA−gentamicin C1a complex. Gentamicin C1a is in red and nitrogen atoms are highlighted in blue. Inter-ring hydrogen bonds are represented by dashed lines. Gentamicin C1a rings are labeled as in Figure 1.