Table 1.

NMR restraints and structural statistics

Distance restraints
Intranucleotide NOEs	370
Internucleotide NOEs (n, n + 1)	266
Long-range NOEs (n, n + m, m > 1)	57
Torsion angle restraints	130
Hydrogen bond restraints	32
Residual dipolar couplings	51
Base pair planarity restraints	22
Total number of restraints	928 (∼28/nt)
NOE violations > 0.3 Å	2.2 ± 1.2
Maximum NOE violations (Å)	0.38 ± 0.08
Deviations from idealized covalent geometry
Bonds (Å)	0.009 ± 0.000
Angles (°)	1.62 ± 0.12
Pairwise all heavy atom RMSD from average structure (Å)
Overall	0.76 ± 0.20
Without the asymmetric internal loop	0.76 ± 0.24
Without the GAAA tetraloop	0.63 ± 0.29
Without the first GC base pair	0.74 ± 0.22
Without the GAAA tetraloop and the first GC base pair	0.62 ± 0.31
Without the asymmetric internal loop and the GAAA tetraloop	0.64 ± 0.33
Without the asymmetric internal loop, the GAAA tetraloop and the first GC base pair	0.62 ± 0.36