SOLUTION NMR Experimental Data

Experimental Details
Sample Conditions
Sample Contents5 mM kalata B1; 90% H2O, 10% D2O
Solvent90% H2O/10% D2O
Ionic Strength0
Temperature (K)298
Experiment(s):2D NOESY
Spectrometer Information
Manufacturer Model Field Strength
Bruker DMX 750.0
NMR Refinement
Method torsion angle dynamics
Details Structures are based on a total of 333 distance constraints. This includes 6 upper and 6 lower limits defining 3 disulfide bonds, as well as 3 upper and 3 lower limits defining a peptide bond cyclizing the peptide backbone. Residue numbering follows the original description of citation 1, except that for the purposes of structure calculations, the N-terminal residue was taken as Asn8. Therefore, residues 30-36 in this deposition correspond to residues 1-7 in citation 1 and related PDB entry 1kal. Structures were refined in the absence of any artificial constraints defining disulfide bonds until all NOEs had been assigned and low target functions were achieved (tf=0.6). 15 additional calculations were performed with these input data and the inclusion of constraints defining all possible disulfide pairing combinations. The structures containing disulfides between [5(34)-13], [17-29] and [22-27] displayed the lowest target function (0.74, second lowest was 1.54). On the basis of this result and analysis of NOEs observed between Cys sidechain protons, this disulfide bonding arrangement was assumed to be correct and served as the basis for this deposition.
NMR Ensemble Information
Conformer Selection Criteria target function
Conformers Calculated Total Number 50
Conformers Submitted Total Number 20
Additional NMR Experimental Information
1 Structure was determined using NOEs from a single 100 ms mixing time NOESY experiment
Computation: NMR Software
# Classification Software Name Author
1 refinement version: 1.5 DYANA P. Guentert
2 collection version: 2.6 XWINNMR Bruker
3 data analysis version: 1.3.11 Xeasy C. Bartels