Table 2. Determination of the NMR structure, a reference crystal structure and a reference NMR structure of the protein A2LD1: input for the structure calculations and characterization of bundles of 20 energy-minimized CYANA conformers representing the structures.

Except for the top six entries and the Ramachandran plot statistics, average values and standard deviations for the 20 conformers are given.

	NMR structure†	Reference crystal structure‡	Reference NMR structure§
NOE upper distance limits	3175	5557	5111
Intra-residual	615	1088	1301
Short-range	884	1415	1518
Medium-range	446	884	748
Long-range	1230	2170	1544
Dihedral angle constraints	461	502	506
Residual target-function value (Å2)	2.58 ± 0.31	1.86 ± 0.38	2.31 ± 0.48
Residual NOE violations
No. ≥ 0.1 Å	28 ± 5	12 ± 2	11 ± 3
Maximum (Å)	0.15 ± 0.04	0.19 ± 0.04	0.19 ± 0.01
Residual dihedral angle violations
No. ≥ 2.5°	0 ± 1	2 ± 1	1 ± 1
Maximum (°)	2.5 ± 1.5	3.3 ± 0.5	3.1 ± 1.4
AMBER energies (kcal mol−1)
Total	−5427 ± 89	−5506 ± 71	−5142 ± 117
van der Waals	−512 ± 24	−464 ± 18	−377 ± 33
Electrostatic	−6276 ± 99	−6584 ± 57	−6330 ± 97
R.m.s.d. from mean coordinates (Å)
Backbone (2–144)	0.65 ± 0.11	0.34 ± 0.05	0.71 ± 0.09
All heavy atoms (2–144)	1.06 ± 0.13	0.70 ± 0.05	1.14 ± 0.09
Backbone ( ≤ 0.64 Å)	0.49 ± 0.06	0.33 ± 0.05	0.54 ± 0.09
All heavy atoms ( ≤ 0.64 Å)	0.84 ± 0.05	0.64 ± 0.05	0.86 ± 0.09
Ramachandran plot statistics
Most favored regions (%)	76.7	87.0	75.7
Additional allowed regions (%)	21.1	11.8	22.4
Generously allowed regions (%)	1.6	0.6	1.3
Disallowed regions (%)	0.6	0.5	0.5

^†Structure calculated from the experimental NMR data. The top six entries represent the input generated in the final cycle of the ATNOS/CANDID and CYANA calculation.

^‡Structure calculated with CYANA from conformational constraints derived from the molecular model representing the crystal structure and subjected to the same energy minimization as the experimental NMR structure (Jaudzems et al., 2010 ▶).

^§Structure calculated with CYANA from conformational constraints derived from the bundle of 20 molecular models representing the NMR structure and subjected to the same energy minimization as the experimental NMR structure (Jaudzems et al., 2010 ▶).

^¶1 cal = 4.186 J.

^††The numbers in parentheses indicate the residues for which the r.m.s.d. was calculated. Residues with ≤ 0.64 Å are identified in Fig. 2 ▶(c).

^‡‡As determined by PROCHECK (Laskowski et al., 1993 ▶). The equivalent anaysis for the crystal structure deposited in the PDB (1vkb) results in 99.3% favored, 0.7% additionally allowed, 0% generously allowed and 0% disallowed.