Please note that you are looking at an abridged version of the output (all checks that gave normal results have been removed from this report). You can have a look at the Full report instead.
269 V21 ( 262-) A -
Plausible side chain atoms were detected with (near) zero occupancy
When crystallographers do not see an atom they either leave it out completely, or give it an occupancy of zero or a very high B-factor. WHAT IF neglects these atoms. In this case some atoms were found with zero occupancy, but with coordinates that place them at a plausible position. Although WHAT IF knows how to deal with missing side chain atoms, validation will go more reliable if all atoms are presnt. So, please consider manually setting the occupancy of the listed atoms at 1.0.
6 LYS ( 9-) A - CE 6 LYS ( 9-) A - NZ 42 LYS ( 45-) A - NZ 77 LYS ( 80-) A - NZ 129 LYS ( 133-) A - NZ 155 LYS ( 159-) A - CE 155 LYS ( 159-) A - NZ 164 LYS ( 168-) A - NZ 168 LYS ( 172-) A - CE 168 LYS ( 172-) A - NZ 171 ASP ( 175-) A - OD2 235 GLU ( 239-) A - CG 235 GLU ( 239-) A - CD 235 GLU ( 239-) A - OE1 235 GLU ( 239-) A - OE2 249 ASN ( 253-) A - CB 249 ASN ( 253-) A - CG 249 ASN ( 253-) A - OD1 249 ASN ( 253-) A - ND2 251 GLN ( 255-) A - OE1 251 GLN ( 255-) A - NE2 253 LYS ( 257-) A - NZ 257 LYS ( 261-) A - CE 257 LYS ( 261-) A - NZ
In a colour picture, the residues that are part of a helix are shown in blue, strand residues in red. Preferred regions for helical residues are drawn in blue, for strand residues in red, and for all other residues in green. A full explanation of the Ramachandran plot together with a series of examples can be found at the WHAT_CHECK website.
Chain identifier: A
Coordinate problems, unexpected atoms, B-factor and occupancy checks
Warning: Missing atoms
The atoms listed in the table below are missing from the entry. If many atoms
are missing, the other checks can become less sensitive. Be aware that it
often happens that groups at the termini of DNA or RNA are really missing,
so that the absence of these atoms normally is neither an error nor the
result of poor electron density. Some of the atoms listed here might also be
listed by other checks, most noticeably by the options in the previous
section that list missing atoms in several categories. The plausible atoms
with zero occupancy are not listed here, as they already got assigned a
non-zero occupancy, and thus are no longer 'missing'.
6 LYS ( 9-) A CD 42 LYS ( 45-) A CE 66 GLU ( 69-) A OE1 77 LYS ( 80-) A CE 129 LYS ( 133-) A CE 155 LYS ( 159-) A CD 251 GLN ( 255-) A CD 253 LYS ( 257-) A CE 257 LYS ( 261-) A CD
Atoms want to move. That is the direct result of the second law of thermodynamics, in a somewhat weird way of thinking. Any way, many atoms seem to have more than one position where they like to sit, and they jump between them. The population difference between those sites (which is related to their energy differences) is seen in the occupancy factors. As also for atoms it is 'to be or not to be', these occupancies should add up to 1.0. Obviously, it is possible that they add up to a number less than 1.0, in cases where there are yet more, but undetected' rotamers/positions in play, but also in those cases a warning is in place as the information shown in the PDB file is less certain than it could have been. The residues listed below contain atoms that have an occupancy greater than zero, but all their alternates do not add up to one.
WARNING. Presently WHAT CHECK only deals with a maximum of two alternate positions. A small number of atoms in the PDB has three alternates. In those cases the warning given here should obviously be neglected! In a next release we will try to fix this.
23 GLU ( 26-) A 0.50 82 ASP ( 85-) A 0.50
Obviously, the temperature at which the X-ray data was collected has some importance too:
Number of TLS groups mentione in PDB file header: 0
Crystal temperature (K) :100.000
Note: B-factor plot
The average atomic B-factor per residue is plotted as function of the residue
Chain identifier: A
Warning: Low bond length variability
Bond lengths were found to deviate less than normal from the mean Engh and
Huber [REF] and/or Parkinson et al [REF] standard bond lengths. The RMS
Z-score given below is expected to be near 1.0 for a normally restrained
data set. The fact that it is lower than 0.667 in this structure might
indicate that too-strong restraints have been used in the refinement. This
can only be a problem for high resolution X-ray structures.
RMS Z-score for bond lengths: 0.462
RMS-deviation in bond distances: 0.011
Warning: Possible cell scaling problem
Comparison of bond distances with Engh and Huber [REF] standard values for
protein residues and Parkinson et al [REF] values for DNA/RNA shows a
significant systematic deviation. It could be that the unit cell used in
refinement was not accurate enough. The deformation matrix given below gives
the deviations found: the three numbers on the diagonal represent the
relative corrections needed along the A, B and C cell axis. These values are
1.000 in a normal case, but have significant deviations here (significant at
the 99.99 percent confidence level)
There are a number of different possible causes for the discrepancy. First the cell used in refinement can be different from the best cell calculated. Second, the value of the wavelength used for a synchrotron data set can be miscalibrated. Finally, the discrepancy can be caused by a dataset that has not been corrected for significant anisotropic thermal motion.
Please note that the proposed scale matrix has NOT been restrained to obey the space group symmetry. This is done on purpose. The distortions can give you an indication of the accuracy of the determination.
If you intend to use the result of this check to change the cell dimension of your crystal, please read the extensive literature on this topic first. This check depends on the wavelength, the cell dimensions, and on the standard bond lengths and bond angles used by your refinement software.
Unit Cell deformation matrix
| 0.996005 0.000035 -0.000242| | 0.000035 0.997248 -0.000059| | -0.000242 -0.000059 0.997189|Proposed new scale matrix
| 0.023827 0.000000 0.006041| | 0.000000 0.024501 0.000001| | 0.000003 0.000000 0.014361|With corresponding cell
A = 41.972 B = 40.814 C = 71.839 Alpha= 90.004 Beta= 104.240 Gamma= 90.000
The CRYST1 cell dimensions
A = 42.140 B = 40.927 C = 72.036 Alpha= 90.000 Beta= 104.230 Gamma= 90.000
(Under-)estimated Z-score: 7.003
Warning: Unusual bond angles
The bond angles listed in the table below were found to deviate more than 4
sigma from standard bond angles (both standard values and sigma for protein
residues have been taken from Engh and Huber [REF], for DNA/RNA from
Parkinson et al [REF]). In the table below for each strange angle the bond
angle and the number of standard deviations it differs from the standard
values is given. Please note that disulphide bridges are neglected. Atoms
starting with "-" belong to the previous residue in the sequence.
171 ASP ( 175-) A CB CG OD2 102.28 -7.0
171 ASP ( 175-) A 18.63
These scores give an impression of how `normal' the torsion angles in protein residues are. All torsion angles except omega are used for calculating a `normality' score. Average values and standard deviations were obtained from the residues in the WHAT IF database. These are used to calculate Z-scores. A residue with a Z-score of below -2.0 is poor, and a score of less than -3.0 is worrying. For such residues more than one torsion angle is in a highly unlikely position.
80 PRO ( 83-) A -2.3 172 PHE ( 176-) A -2.2 159 VAL ( 163-) A -2.2 89 GLN ( 92-) A -2.1 27 PRO ( 30-) A -2.0 147 GLY ( 151-) A -2.0
Residues with `forbidden' phi-psi combinations are listed, as well as residues with unusual omega angles (deviating by more than 3 sigma from the normal value). Please note that it is normal if about 5 percent of the residues is listed here as having unusual phi-psi combinations.
26 SER ( 29-) A PRO omega poor 54 LEU ( 57-) A omega poor 72 ASP ( 75-) A Poor phi/psi 89 GLN ( 92-) A omega poor 92 PHE ( 95-) A omega poor 108 LYS ( 111-) A Poor phi/psi 125 GLY ( 129-) A Poor phi/psi 174 ASN ( 178-) A Poor phi/psi 187 TYR ( 191-) A omega poor 193 SER ( 197-) A omega poor 197 PRO ( 201-) A PRO omega poor 199 LEU ( 203-) A Poor phi/psi 203 VAL ( 207-) A omega poor 231 GLY ( 235-) A omega poor 248 LYS ( 252-) A Poor phi/psi chi-1/chi-2 correlation Z-score : -0.317
For this check, backbone conformations are compared with database structures using C-alpha superpositions with some restraints on the backbone oxygen positions.
A residue mentioned in the table can be part of a strange loop, or there might be something wrong with it or its directly surrounding residues. There are a few of these in every protein, but in any case it is worth looking at!
4 TYR ( 7-) A 0 7 HIS ( 10-) A 0 16 ASP ( 19-) A 0 17 PHE ( 20-) A 0 21 LYS ( 24-) A 0 24 ARG ( 27-) A 0 25 GLN ( 28-) A 0 26 SER ( 29-) A 0 47 SER ( 50-) A 0 51 ALA ( 54-) A 0 59 ASN ( 62-) A 0 61 HIS ( 64-) A 0 69 ASP ( 72-) A 0 70 SER ( 73-) A 0 72 ASP ( 75-) A 0 73 LYS ( 76-) A 0 74 ALA ( 77-) A 0 77 LYS ( 80-) A 0 80 PRO ( 83-) A 0 81 LEU ( 84-) A 0 82 ASP ( 85-) A 0 89 GLN ( 92-) A 0 96 SER ( 99-) A 0 100 GLN ( 103-) A 0 103 GLU ( 106-) A 0And so on for a total of 115 lines.
The contact distances of all atom pairs have been checked. Two atoms are said to `bump' if they are closer than the sum of their Van der Waals radii minus 0.40 Angstrom. For hydrogen bonded pairs a tolerance of 0.55 Angstrom is used. The first number in the table tells you how much shorter that specific contact is than the acceptable limit. The second distance is the distance between the centres of the two atoms. Although we believe that two water atoms at 2.4 A distance are too close, we only report water pairs that are closer than this rather short distance.
The last text-item on each line represents the status of the atom pair. If the final column contains the text 'HB', the bump criterion was relaxed because there could be a hydrogen bond. Similarly relaxed criteria are used for 1-3 and 1-4 interactions (listed as 'B2' and 'B3', respectively). BL indicates that the B-factors of the clashing atoms have a low B-factor thereby making this clash even more worrisome. INTRA and INTER indicate whether the clashes are between atoms in the same asymmetric unit, or atoms in symmetry related asymmetric units, respectively.
261 UNX ( 265-) A UNK <-> 262 UNX ( 266-) A UNK 1.52 1.48 INTRA 263 UNX ( 267-) A UNK <-> 264 UNX ( 268-) A UNK 1.47 1.53 INTRA 260 UNX ( 264-) A UNK <-> 261 UNX ( 265-) A UNK 1.47 1.53 INTRA 266 UNX ( 270-) A UNK <-> 267 UNX ( 271-) A UNK 1.47 1.53 INTRA 262 UNX ( 266-) A UNK <-> 264 UNX ( 268-) A UNK 0.77 2.43 INTRA 263 UNX ( 267-) A UNK <-> 265 UNX ( 269-) A UNK 0.74 2.46 INTRA 260 UNX ( 264-) A UNK <-> 262 UNX ( 266-) A UNK 0.72 2.48 INTRA 261 UNX ( 265-) A UNK <-> 263 UNX ( 267-) A UNK 0.70 2.50 INTRA 265 UNX ( 269-) A UNK <-> 267 UNX ( 271-) A UNK 0.70 2.50 INTRA 262 UNX ( 266-) A UNK <-> 266 UNX ( 270-) A UNK 0.69 2.51 INTRA 261 UNX ( 265-) A UNK <-> 267 UNX ( 271-) A UNK 0.61 2.59 INTRA 133 GLN ( 137-) A NE2 <-> 270 HOH ( 438 ) A O 0.42 2.28 INTRA 262 UNX ( 266-) A UNK <-> 265 UNX ( 269-) A UNK 0.39 2.81 INTRA 260 UNX ( 264-) A UNK <-> 267 UNX ( 271-) A UNK 0.37 2.83 INTRA 264 UNX ( 268-) A UNK <-> 267 UNX ( 271-) A UNK 0.29 2.91 INTRA 263 UNX ( 267-) A UNK <-> 266 UNX ( 270-) A UNK 0.26 2.94 INTRA 33 HIS ( 36-) A ND1 <-> 270 HOH ( 411 ) A O 0.24 2.46 INTRA 230 GLU ( 234-) A N <-> 270 HOH ( 417 ) A O 0.17 2.53 INTRA 270 HOH ( 297 ) A O <-> 270 HOH ( 402 ) A O 0.17 2.03 INTRA 270 HOH ( 338 ) A O <-> 270 HOH ( 490 ) A O 0.12 2.08 INTRA 59 ASN ( 62-) A ND2 <-> 64 ASN ( 67-) A ND2 0.12 2.73 INTRA 12 HIS ( 15-) A ND1 <-> 15 LYS ( 18-) A NZ 0.11 2.89 INTRA BL 72 ASP ( 75-) A OD1 <-> 86 ARG ( 89-) A NE 0.10 2.60 INTRA 129 LYS ( 133-) A NZ <-> 270 HOH ( 434 ) A O 0.04 2.66 INTRA 109 LYS ( 112-) A NZ <-> 270 HOH ( 389 ) A O 0.04 2.66 INTRA 4 TYR ( 7-) A C <-> 270 HOH ( 464 ) A O 0.02 2.78 INTRA 104 HIS ( 107-) A NE2 <-> 190 TYR ( 194-) A OH 0.01 2.69 INTRA BL 48 TYR ( 51-) A OH <-> 119 HIS ( 122-) A NE2 0.01 2.69 INTRA BL
Chain identifier: A
Warning: Abnormal packing environment for some residues
The residues listed in the table below have an unusual packing environment.
The packing environment of the residues is compared with the average packing environment for all residues of the same type in good PDB files. A low packing score can indicate one of several things: Poor packing, misthreading of the sequence through the density, crystal contacts, contacts with a co-factor, or the residue is part of the active site. It is not uncommon to see a few of these, but in any case this requires further inspection of the residue.
7 HIS ( 10-) A -6.49 132 GLN ( 136-) A -5.70 97 LEU ( 100-) A -5.25 249 ASN ( 253-) A -5.21
Chain identifier: A
Warning: Low packing Z-score for some residues
The residues listed in the table below have an unusual packing
environment according to the 2nd generation packing check. The score
listed in the table is a packing normality Z-score: positive means
better than average, negative means worse than average. Only residues
scoring less than -2.50 are listed here. These are the unusual
residues in the structure, so it will be interesting to take a
special look at them.
251 GLN ( 255-) A -2.86 15 LYS ( 18-) A -2.58
Chain identifier: A
Water, ion, and hydrogenbond related checks
Warning: Water molecules need moving
The water molecules listed in the table below were found to be significantly
closer to a symmetry related non-water molecule than to the ones given in the
coordinate file. For optimal viewing convenience revised coordinates for
these water molecules should be given.
The number in brackets is the identifier of the water molecule in the input file. Suggested coordinates are also given in the table. Please note that alternative conformations for protein residues are not taken into account for this calculation. If you are using WHAT IF / WHAT-CHECK interactively, then the moved waters can be found in PDB format in the file: MOVEDH2O.pdb.
270 HOH ( 277 ) A O 11.36 1.48 26.03 270 HOH ( 280 ) A O -7.16 -8.75 32.75 270 HOH ( 291 ) A O -17.22 -7.38 39.95 270 HOH ( 301 ) A O 13.20 -3.76 13.49 270 HOH ( 302 ) A O 8.73 -3.74 21.15 270 HOH ( 307 ) A O -15.75 9.09 -1.97 270 HOH ( 310 ) A O -1.08 9.26 28.13 270 HOH ( 325 ) A O 9.12 -4.65 23.57 270 HOH ( 326 ) A O 13.57 0.25 24.54 270 HOH ( 327 ) A O 1.86 12.42 23.20 270 HOH ( 337 ) A O -14.77 20.13 17.61 270 HOH ( 348 ) A O -1.44 11.15 26.18 270 HOH ( 354 ) A O 7.83 -5.87 -10.71 270 HOH ( 361 ) A O -19.39 17.22 6.06 270 HOH ( 362 ) A O 13.21 -5.94 24.63 270 HOH ( 367 ) A O 1.20 -6.52 34.66 270 HOH ( 368 ) A O -5.94 -11.42 36.59 270 HOH ( 407 ) A O -13.37 19.81 14.50 270 HOH ( 481 ) A O -26.67 -6.34 5.45
270 HOH ( 403 ) A O 270 HOH ( 405 ) A O 270 HOH ( 460 ) A O Metal-coordinating Histidine residue 91 fixed to 1 Metal-coordinating Histidine residue 93 fixed to 1 Metal-coordinating Histidine residue 116 fixed to 1
50 GLN ( 53-) A 133 GLN ( 137-) A
Hydrogen bond donors that are buried inside the protein normally use all of their hydrogens to form hydrogen bonds within the protein. If there are any non hydrogen bonded buried hydrogen bond donors in the structure they will be listed here. In very good structures the number of listed atoms will tend to zero.
Waters are not listed by this option.
4 TYR ( 7-) A N 28 VAL ( 31-) A N 55 ARG ( 58-) A NE 55 ARG ( 58-) A NH2 71 GLN ( 74-) A N 97 LEU ( 100-) A N 196 THR ( 200-) A N 200 LEU ( 204-) A N 226 ASN ( 230-) A ND2 228 ASN ( 232-) A N 241 TRP ( 245-) A N 256 PHE ( 260-) A N Only metal coordination for 93 HIS ( 96-) A NE2 Only metal coordination for 116 HIS ( 119-) A ND1
The output gives the ion, the valency score for the ion itself, the valency score for the suggested alternative ion, and a series of possible comments *1 indicates that the suggested alternate atom type has been observed in the PDB file at another location in space. *2 indicates that WHAT IF thinks to have found this ion type in the crystallisation conditions as described in the REMARK 280 cards of the PDB file. *S Indicates that this ions is located at a special position (i.e. at a symmetry axis). N4 stands for NH4+.
259 NA ( 263-) A -.- -.- Too few ligands (1)
The score listed is the valency score. This number should be close to (preferably a bit above) 1.0 for the suggested ion to be a likely alternative for the water molecule. Ions listed in brackets are good alternate choices. *1 indicates that the suggested ion-type has been observed elsewhere in the PDB file too. *2 indicates that the suggested ion-type has been observed in the REMARK 280 cards of the PDB file. Ion-B and ION-B indicate that the B-factor of this water is high, or very high, respectively. H2O-B indicates that the B-factors of atoms that surround this water/ion are suspicious. See: swift.cmbi.ru.nl/teach/theory/ for a detailed explanation.
270 HOH ( 378 ) A O 1.02 K 4 Ion-B 270 HOH ( 488 ) A O 0.96 NA 5 *1 and *2
161 ASP ( 165-) A H-bonding suggests Asn
The second part of the table mostly gives an impression of how well the model conforms to common refinement restraint values. The first part of the table shows a number of global quality indicators.
Structure Z-scores, positive is better than average:
1st generation packing quality : -0.268 2nd generation packing quality : 0.505 Ramachandran plot appearance : -1.219 chi-1/chi-2 rotamer normality : -0.317 Backbone conformation : -0.937
Bond lengths : 0.462 (tight) Bond angles : 0.680 Omega angle restraints : 1.124 Side chain planarity : 1.956 Improper dihedral distribution : 0.839 B-factor distribution : 0.460 Inside/Outside distribution : 0.955
The second part of the table mostly gives an impression of how well the model conforms to common refinement restraint values. The first part of the table shows a number of global quality indicators, which have been calibrated against structures of similar resolution.
Resolution found in PDB file : 1.44
Structure Z-scores, positive is better than average:
1st generation packing quality : -0.0 2nd generation packing quality : -0.2 Ramachandran plot appearance : -1.6 chi-1/chi-2 rotamer normality : -0.8 Backbone conformation : -1.5
Bond lengths : 0.462 (tight) Bond angles : 0.680 Omega angle restraints : 1.124 Side chain planarity : 1.956 Improper dihedral distribution : 0.839 B-factor distribution : 0.460 Inside/Outside distribution : 0.955 ==============
WHAT IF G.Vriend, WHAT IF: a molecular modelling and drug design program, J. Mol. Graph. 8, 52--56 (1990). WHAT_CHECK (verification routines from WHAT IF) R.W.W.Hooft, G.Vriend, C.Sander and E.E.Abola, Errors in protein structures Nature 381, 272 (1996). (see also http://swift.cmbi.ru.nl/gv/whatcheck for a course and extra inform Bond lengths and angles, protein residues R.Engh and R.Huber, Accurate bond and angle parameters for X-ray protein structure refinement, Acta Crystallogr. A47, 392--400 (1991). Bond lengths and angles, DNA/RNA G.Parkinson, J.Voitechovsky, L.Clowney, A.T.Bruenger and H.Berman, New parameters for the refinement of nucleic acid-containing structures Acta Crystallogr. D52, 57--64 (1996). DSSP W.Kabsch and C.Sander, Dictionary of protein secondary structure: pattern recognition of hydrogen bond and geometrical features Biopolymers 22, 2577--2637 (1983). Hydrogen bond networks R.W.W.Hooft, C.Sander and G.Vriend, Positioning hydrogen atoms by optimizing hydrogen bond networks in protein structures PROTEINS, 26, 363--376 (1996). Matthews' Coefficient B.W.Matthews Solvent content of Protein Crystals J. Mol. Biol. 33, 491--497 (1968). Protein side chain planarity R.W.W. Hooft, C. Sander and G. Vriend, Verification of protein structures: side-chain planarity J. Appl. Cryst. 29, 714--716 (1996). Puckering parameters D.Cremer and J.A.Pople, A general definition of ring puckering coordinates J. Am. Chem. Soc. 97, 1354--1358 (1975). Quality Control G.Vriend and C.Sander, Quality control of protein models: directional atomic contact analysis, J. Appl. Cryst. 26, 47--60 (1993). Ramachandran plot G.N.Ramachandran, C.Ramakrishnan and V.Sasisekharan, Stereochemistry of Polypeptide Chain Conformations J. Mol. Biol. 7, 95--99 (1963). Symmetry Checks R.W.W.Hooft, C.Sander and G.Vriend, Reconstruction of symmetry related molecules from protein data bank (PDB) files J. Appl. Cryst. 27, 1006--1009 (1994). Ion Checks I.D.Brown and K.K.Wu, Empirical Parameters for Calculating Cation-Oxygen Bond Valences Acta Cryst. B32, 1957--1959 (1975). M.Nayal and E.Di Cera, Valence Screening of Water in Protein Crystals Reveals Potential Na+ Binding Sites J.Mol.Biol. 256 228--234 (1996). P.Mueller, S.Koepke and G.M.Sheldrick, Is the bond-valence method able to identify metal atoms in protein structures? Acta Cryst. D 59 32--37 (2003). Checking checks K.Wilson, C.Sander, R.W.W.Hooft, G.Vriend, et al. Who checks the checkers J.Mol.Biol. (1998) 276,417-436.