Table 1.

NMR and refinement statistics.

	HACS1 SH3 domain
NMR distance and dihedral constraints
Distance constraints
Total NOE	1148
Intra-residue	495
Inter-residue
Sequential (|i – j | = 1)	245
Medium-range (|i – j | < 4)	75
Long-range (|i – j | > 5)	333
Hydrogen bond restraints a	9
Hydrogen bonds inferred b	25
Total dihedral angle restraints
ϕ	61
ψ	61
Total RDCs	49
Q before refinement with RDCs (%)	41
Q after refinement with RDCs (%)	11
Structure statistics
Violations (mean and s.d.)
Distance constraints (Å)	0.0349 ± 0.0023
Dihedral angle constraints (°)	0.4255 ± 0.0153
Deviations from idealized geometry
Bond lengths (Å)	0.0025 ± 0.0005
Bond angles (°)	0.4255 ± 0.0153
Impropers (°)	0.3185 ± 0.0134
Average pairwise r.m.s. deviation among 20 structures (Å)
Heavy	0.32
Backbone	1.16

a hydrogen bond restraints submitted to the HBDA module of XPLOR 2.52.

b hydrogen bonds inferred by the HBDB module of XPLOR 2.52.