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.
172 MNL ( 8-) C - 173 SAR ( 7-) C - 174 ABA ( 6-) C - 175 BMT ( 5-) C - 176 MVA ( 4-) C - 177 DAL ( 1-) C -
For example, an aspartic acid can be protonated on one of its delta oxygens. This is possible because the one delta oxygen 'helps' the other one holding that proton. However, if a delta oxygen has a group bound to it, then it can no longer 'help' the other delta oxygen bind the proton. However, both delta oxygens, in principle, can still be hydrogen bond acceptors. Such problems can occur in the amino acids Asp, Glu, and His. I have opted, for now to simply allow no hydrogen bonds at all for any atom in any side chain that somewhere has a 'funny' group attached to it. I know this is wrong, but there are only 12 hours in a day.
166 MLE ( 2-) C - N bound to 177 DAL ( 1-) C - C
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: Artificial side chains detected
At least two residues (listed in the table below) were detected with chi-1
equal to 0.00 or 180.00. Since this is highly unlikely to occur accidentally,
the listed residues have probably not been refined.
166 MLE ( 2-) C 167 MLE ( 3-) C 169 MLE ( 10-) C
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.
6 VAL ( 6-) A 0.46 21 SER ( 21-) A 0.51 115 CYS ( 115-) A 0.40
Obviously, the temperature at which the X-ray data was collected has some importance too:
Temperature cannot be read from the PDB file. This most likely means that
the temperature is listed as NULL (meaning unknown) in the PDB file.
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: 0.463
RMS-deviation in bond distances: 0.011
Warning: Torsion angle evaluation shows unusual residues
The residues listed in the table below contain bad or abnormal
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.
29 VAL ( 29-) A -2.3 61 MET ( 61-) A -2.3 134 GLU ( 134-) A -2.2 69 ARG ( 69-) A -2.2 109 GLY ( 109-) A -2.1
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.
70 HIS ( 70-) A Poor phi/psi 106 ASN ( 106-) A Poor phi/psi chi-1/chi-2 correlation Z-score : -1.106
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!
12 VAL ( 12-) A 0 16 PRO ( 16-) A 0 25 PHE ( 25-) A 0 26 ALA ( 26-) A 0 28 LYS ( 28-) A 0 29 VAL ( 29-) A 0 43 GLU ( 43-) A 0 44 LYS ( 44-) A 0 46 PHE ( 46-) A 0 48 TYR ( 48-) A 0 49 LYS ( 49-) A 0 51 SER ( 51-) A 0 53 PHE ( 53-) A 0 54 HIS ( 54-) A 0 58 PRO ( 58-) A 0 60 PHE ( 60-) A 0 61 MET ( 61-) A 0 68 THR ( 68-) A 0 70 HIS ( 70-) A 0 71 ASN ( 71-) A 0 73 THR ( 73-) A 0 79 TYR ( 79-) A 0 81 GLU ( 81-) A 0 83 PHE ( 83-) A 0 86 GLU ( 86-) A 0And so on for a total of 83 lines.
Standard deviation of omega values : 1.872
Error: Abnormally short interatomic distances
The pairs of atoms listed in the table below have an unusually short
interactomic distance; each bump is listed in only one direction.
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.
174 ABA ( 6-) C N <-> 175 BMT ( 5-) C C 1.37 1.33 INTRA B3 170 ALA ( 11-) C C <-> 177 DAL ( 1-) C N 1.37 1.33 INTRA B3 168 VAL ( 9-) C N <-> 172 MNL ( 8-) C C 1.37 1.33 INTRA B3 166 MLE ( 2-) C N <-> 177 DAL ( 1-) C C 1.37 1.33 INTRA B3 172 MNL ( 8-) C N <-> 173 SAR ( 7-) C C 1.37 1.33 INTRA B3 173 SAR ( 7-) C N <-> 174 ABA ( 6-) C C 1.37 1.33 INTRA B3 167 MLE ( 3-) C C <-> 176 MVA ( 4-) C N 1.36 1.34 INTRA B3 175 BMT ( 5-) C N <-> 176 MVA ( 4-) C C 1.36 1.34 INTRA B3 166 MLE ( 2-) C CA <-> 177 DAL ( 1-) C C 0.78 2.42 INTRA 175 BMT ( 5-) C CA <-> 176 MVA ( 4-) C C 0.78 2.42 INTRA 168 VAL ( 9-) C CA <-> 172 MNL ( 8-) C C 0.77 2.43 INTRA 175 BMT ( 5-) C CN <-> 176 MVA ( 4-) C C 0.69 2.51 INTRA 170 ALA ( 11-) C CA <-> 177 DAL ( 1-) C N 0.69 2.41 INTRA 1 MET ( 1-) A N <-> 178 HOH (2001 ) A O 0.68 2.02 INTRA BF 167 MLE ( 3-) C CA <-> 176 MVA ( 4-) C N 0.67 2.43 INTRA 172 MNL ( 8-) C CA <-> 173 SAR ( 7-) C C 0.67 2.43 INTRA 174 ABA ( 6-) C CA <-> 175 BMT ( 5-) C C 0.67 2.43 INTRA 166 MLE ( 2-) C CN <-> 177 DAL ( 1-) C C 0.66 2.54 INTRA 173 SAR ( 7-) C CA <-> 174 ABA ( 6-) C C 0.59 2.41 INTRA 172 MNL ( 8-) C CM1 <-> 173 SAR ( 7-) C C 0.56 2.54 INTRA 173 SAR ( 7-) C CN <-> 174 ABA ( 6-) C C 0.55 2.55 INTRA 52 CYS ( 52-) A SG <-> 155 LYS ( 155-) A NZ 0.53 2.77 INTRA 167 MLE ( 3-) C O <-> 176 MVA ( 4-) C N 0.45 2.25 INTRA 170 ALA ( 11-) C O <-> 177 DAL ( 1-) C N 0.44 2.26 INTRA 175 BMT ( 5-) C CN <-> 176 MVA ( 4-) C CA 0.30 2.90 INTRA 166 MLE ( 2-) C CN <-> 177 DAL ( 1-) C CA 0.29 2.91 INTRA 167 MLE ( 3-) C CA <-> 176 MVA ( 4-) C CN 0.27 2.93 INTRA 52 CYS ( 52-) A SG <-> 178 HOH (2151 ) A O 0.24 2.76 INTRA 70 HIS ( 70-) A CD2 <-> 178 HOH (2057 ) A O 0.19 2.61 INTRA 172 MNL ( 8-) C CM1 <-> 173 SAR ( 7-) C CA 0.18 2.92 INTRA 1 MET ( 1-) A SD <-> 2 VAL ( 2-) A N 0.16 3.04 INTRA BF 52 CYS ( 52-) A CB <-> 155 LYS ( 155-) A NZ 0.14 2.96 INTRA 65 GLY ( 65-) A N <-> 178 HOH (2067 ) A O 0.13 2.57 INTRA BL 173 SAR ( 7-) C CN <-> 174 ABA ( 6-) C CA 0.12 2.98 INTRA 6 VAL ( 6-) A CG1 <-> 7 PHE ( 7-) A N 0.10 2.90 INTRA BL 175 BMT ( 5-) C CA <-> 176 MVA ( 4-) C O 0.08 2.72 INTRA 167 MLE ( 3-) C O <-> 176 MVA ( 4-) C CA 0.06 2.74 INTRA 102 ASN ( 102-) A ND2 <-> 178 HOH (2102 ) A O 0.06 2.64 INTRA BL 168 VAL ( 9-) C CA <-> 172 MNL ( 8-) C O 0.06 2.74 INTRA 166 MLE ( 2-) C CA <-> 177 DAL ( 1-) C O 0.04 2.76 INTRA 68 THR ( 68-) A OG1 <-> 75 GLY ( 75-) A N 0.04 2.66 INTRA 144 ARG ( 144-) A O <-> 178 HOH (2143 ) A O 0.03 2.37 INTRA 66 ASP ( 66-) A OD2 <-> 72 GLY ( 72-) A N 0.03 2.67 INTRA BL 96 GLY ( 96-) A N <-> 115 CYS ( 115-) A O 0.02 2.68 INTRA BL 12 VAL ( 12-) A N <-> 15 GLU ( 15-) A O 0.02 2.68 INTRA BL 100 MET ( 100-) A SD <-> 129 PHE ( 129-) A CE1 0.02 3.38 INTRA BL 10 ILE ( 10-) A O <-> 17 LEU ( 17-) A N 0.02 2.68 INTRA BL 55 ARG ( 55-) A O <-> 63 GLN ( 63-) A N 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.
148 ARG ( 148-) A -7.83 144 ARG ( 144-) A -5.42 2 VAL ( 2-) A -5.23 69 ARG ( 69-) A -5.22
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.
120 GLU ( 120-) A -2.84
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.
178 HOH (2007 ) A O 1.29 32.99 11.78
178 HOH (2024 ) A O 178 HOH (2038 ) A O Unrecognized bound group for 167 Bound atom= 176 MVA ( 4-) C N
102 ASN ( 102-) 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.
1 MET ( 1-) A N 19 ARG ( 19-) A NH1 87 ASN ( 87-) A N 102 ASN ( 102-) A N 117 ALA ( 117-) A N 121 TRP ( 121-) A N 154 LYS ( 154-) A N
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.
178 HOH (2090 ) A O 0.97 K 4
81 GLU ( 81-) A H-bonding suggests Gln
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 : -1.089 2nd generation packing quality : -2.108 Ramachandran plot appearance : -0.310 chi-1/chi-2 rotamer normality : -1.106 Backbone conformation : -0.184
Bond lengths : 0.463 (tight) Bond angles : 0.729 Omega angle restraints : 0.340 (tight) Side chain planarity : 0.414 (tight) Improper dihedral distribution : 0.913 B-factor distribution : 0.640 Inside/Outside distribution : 0.918
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 : 1.86
Structure Z-scores, positive is better than average:
1st generation packing quality : -0.6 2nd generation packing quality : -1.5 Ramachandran plot appearance : 0.1 chi-1/chi-2 rotamer normality : -0.5 Backbone conformation : -0.4
Bond lengths : 0.463 (tight) Bond angles : 0.729 Omega angle restraints : 0.340 (tight) Side chain planarity : 0.414 (tight) Improper dihedral distribution : 0.913 B-factor distribution : 0.640 Inside/Outside distribution : 0.918 ==============
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.