WHAT IF Check report

This file was created 2012-01-25 from WHAT_CHECK output by a conversion script. If you are new to WHAT_CHECK, please study the pdbreport pages. There also exists a legend to the output.

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.

Verification log for pdb2dpx.ent

Checks that need to be done early-on in validation

Warning: Problem detected upon counting molecules and matrices

The parameter Z as given on the CRYST card represents the molecular multiplicity in the crystallographic cell. Normally, Z equals the number of matrices of the space group multiplied by the number of NCS relations. The value of Z is multiplied by the integrated molecular weight of the molecules in the file to determine the Matthews coefficient. This relation is being validated in this option. Be aware that the validation can get confused if both multiple copies of the molecule are present in the ATOM records and MTRIX records are present in the header of the PDB file.

Space group as read from CRYST card: P 1 21 1
Number of matrices in space group: 2
Highest polymer chain multiplicity in structure: 1
Highest polymer chain multiplicity according to SEQRES: 2
Such multiplicity differences are not by definition worrisome as it is very
well possible that this merely indicates that it is difficult to superpose
chains due to crystal induced differences
No explicit MTRIX NCS matrices found in the input file
Value of Z as found on the CRYST1 card: 4
Polymer chain multiplicity and SEQRES multiplicity disagree 1 2
Z and NCS seem to support the SEQRES multiplicity (so the matrix counting
problems seem not overly severe)

Warning: Ligands for which a topology was generated automatically

The topology for the ligands in the table below were determined automatically. WHAT IF uses a local copy of Daan van Aalten's Dundee PRODRG server to automatically generate topology information for ligands. For this PDB file that seems to have gone fine, but be aware that automatic topology generation is a complicated task. So, if you get messages that you fail to understand or that you believe are wrong, and one of these ligands is involved, then check the ligand topology first.

 283 GDP   ( 500-)  A  -
 285 GDP   ( 500-)  B  -

Non-validating, descriptive output paragraph

Note: Ramachandran plot

In this Ramachandran plot x-signs represent glycines, squares represent prolines, and plus-signs represent the other residues. If too many plus- signs fall outside the contoured areas then the molecule is poorly refined (or worse). Proline can only occur in the narrow region around phi=-60 that also falls within the other contour islands.

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

Note: Ramachandran plot

Chain identifier: B

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'.

   1 SER   (  90-)  A      OG
  26 GLU   ( 115-)  A      CG
  26 GLU   ( 115-)  A      CD
  26 GLU   ( 115-)  A      OE1
  26 GLU   ( 115-)  A      OE2
  27 HIS   ( 125-)  A      CG
  27 HIS   ( 125-)  A      ND1
  27 HIS   ( 125-)  A      CD2
  27 HIS   ( 125-)  A      CE1
  27 HIS   ( 125-)  A      NE2
  84 ARG   ( 189-)  A      CG
  84 ARG   ( 189-)  A      CD
  84 ARG   ( 189-)  A      NE
  84 ARG   ( 189-)  A      CZ
  84 ARG   ( 189-)  A      NH1
  84 ARG   ( 189-)  A      NH2
  87 ASP   ( 195-)  A      CG
  87 ASP   ( 195-)  A      OD1
  87 ASP   ( 195-)  A      OD2
 101 ARG   ( 209-)  A      CG
 101 ARG   ( 209-)  A      CD
 101 ARG   ( 209-)  A      NE
 101 ARG   ( 209-)  A      CZ
 101 ARG   ( 209-)  A      NH1
 101 ARG   ( 209-)  A      NH2
 146 ARG   ( 254-)  A      CG
 146 ARG   ( 254-)  A      CD
 146 ARG   ( 254-)  A      NE
 146 ARG   ( 254-)  A      CZ
 146 ARG   ( 254-)  A      NH1
 146 ARG   ( 254-)  A      NH2
 174 ASP   ( 128-)  B      CG
 174 ASP   ( 128-)  B      OD1
 174 ASP   ( 128-)  B      OD2
 185 SER   ( 139-)  B      OG
 268 GLN   ( 241-)  B      CG
 268 GLN   ( 241-)  B      CD
 268 GLN   ( 241-)  B      OE1
 268 GLN   ( 241-)  B      NE2
 281 ARG   ( 254-)  B      CG
 281 ARG   ( 254-)  B      CD
 281 ARG   ( 254-)  B      NE
 281 ARG   ( 254-)  B      CZ
 281 ARG   ( 254-)  B      NH1
 281 ARG   ( 254-)  B      NH2

Warning: What type of B-factor?

WHAT IF does not yet know well how to cope with B-factors in case TLS has been used. It simply assumes that the B-factor listed on the ATOM and HETATM cards are the total B-factors. When TLS refinement is used that assumption sometimes is not correct. TLS seems not mentioned in the header of the PDB file. But anyway, if WHAT IF complains about your B-factors, and you think that they are OK, then check for TLS related B-factor problems first.

Obviously, the temperature at which the X-ray data was collected has some importance too:

Crystal temperature (K) :100.000

Note: B-factor plot

The average atomic B-factor per residue is plotted as function of the residue number.

Chain identifier: A

Note: B-factor plot

Chain identifier: B

Nomenclature related problems

Warning: Tyrosine convention problem

The tyrosine residues listed in the table below have their chi-2 not between -90.0 and 90.0

   3 TYR   (  92-)  A
  45 TYR   ( 143-)  A
  64 TYR   ( 169-)  A
 147 TYR   (  92-)  B
 173 TYR   ( 127-)  B
 189 TYR   ( 143-)  B

Warning: Phenylalanine convention problem

The phenylalanine residues listed in the table below have their chi-2 not between -90.0 and 90.0.

 117 PHE   ( 225-)  A
 252 PHE   ( 225-)  B

Warning: Glutamic acid convention problem

The glutamic acid residues listed in the table below have their chi-3 outside the -90.0 to 90.0 range, or their proton on OE1 instead of OE2.

  39 GLU   ( 137-)  A

Geometric checks

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: 0.372
RMS-deviation in bond distances: 0.009

Warning: Low bond angle variability

Bond angles were found to deviate less than normal from the standard bond angles (normal values for protein residues were taken from Engh and Huber [REF], for DNA/RNA from Parkinson et al [REF]). 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 angles: 0.645
RMS-deviation in bond angles: 1.386

Error: Nomenclature error(s)

Checking for a hand-check. WHAT IF has over the course of this session already corrected the handedness of atoms in several residues. These were administrative corrections. These residues are listed here.

  39 GLU   ( 137-)  A

Error: Tau angle problems

The side chains of the residues listed in the table below contain a tau angle (N-Calpha-C) that was found to deviate from te expected value by more than 4.0 times the expected standard deviation. The number in the table is the number of standard deviations this RMS value deviates from the expected value.

 137 GLU   ( 245-)  A    4.62
  54 MET   ( 159-)  A    4.40

Torsion-related checks

Warning: Torsion angle evaluation shows unusual residues

The residues listed in the table below contain bad or abnormal torsion angles.

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.

 191 ILE   ( 145-)  B    -2.3
 187 MET   ( 141-)  B    -2.1

Warning: Backbone evaluation reveals unusual conformations

The residues listed in the table below have abnormal backbone torsion angles.

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.

  14 GLY   ( 103-)  A  Poor phi/psi
  31 ARG   ( 129-)  A  Poor phi/psi
  56 MET   ( 161-)  A  Poor phi/psi
  57 GLY   ( 162-)  A  Poor phi/psi
  96 LYS   ( 204-)  A  Poor phi/psi
 118 ASP   ( 226-)  A  Poor phi/psi
 129 HIS   ( 237-)  A  Poor phi/psi
 131 ASN   ( 239-)  A  Poor phi/psi
 158 GLY   ( 103-)  B  Poor phi/psi
 180 ASP   ( 134-)  B  Poor phi/psi
 231 LYS   ( 204-)  B  Poor phi/psi
 266 ASN   ( 239-)  B  Poor phi/psi
 chi-1/chi-2 correlation Z-score : -1.125

Warning: Unusual rotamers

The residues listed in the table below have a rotamer that is not seen very often in the database of solved protein structures. This option determines for every residue the position specific chi-1 rotamer distribution. Thereafter it verified whether the actual residue in the molecule has the most preferred rotamer or not. If the actual rotamer is the preferred one, the score is 1.0. If the actual rotamer is unique, the score is 0.0. If there are two preferred rotamers, with a population distribution of 3:2 and your rotamer sits in the lesser populated rotamer, the score will be 0.667. No value will be given if insufficient hits are found in the database.

It is not necessarily an error if a few residues have rotamer values below 0.3, but careful inspection of all residues with these low values could be worth it.

  16 SER   ( 105-)  A    0.38

Warning: Unusual backbone conformations

For the residues listed in the table below, the backbone formed by itself and two neighbouring residues on either side is in a conformation that is not seen very often in the database of solved protein structures. The number given in the table is the number of similar backbone conformations in the database with the same amino acid in the centre.

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!

  11 PRO   ( 100-)  A      0
  13 VAL   ( 102-)  A      0
  25 VAL   ( 114-)  A      0
  26 GLU   ( 115-)  A      0
  27 HIS   ( 125-)  A      0
  28 THR   ( 126-)  A      0
  31 ARG   ( 129-)  A      0
  35 VAL   ( 133-)  A      0
  47 ILE   ( 145-)  A      0
  48 TRP   ( 146-)  A      0
  49 LEU   ( 154-)  A      0
  50 PRO   ( 155-)  A      0
  55 ALA   ( 160-)  A      0
  56 MET   ( 161-)  A      0
  58 ASP   ( 163-)  A      0
  67 THR   ( 172-)  A      0
  85 ALA   ( 190-)  A      0
  86 ARG   ( 191-)  A      0
  87 ASP   ( 195-)  A      0
  88 VAL   ( 196-)  A      0
  95 ASN   ( 203-)  A      0
  96 LYS   ( 204-)  A      0
  99 LEU   ( 207-)  A      0
 103 ARG   ( 211-)  A      0
 104 GLU   ( 212-)  A      0
And so on for a total of 91 lines.

Warning: Omega angles too tightly restrained

The omega angles for trans-peptide bonds in a structure are expected to give a gaussian distribution with the average around +178 degrees and a standard deviation around 5.5 degrees. These expected values were obtained from very accurately determined structures. Many protein structures are too tightly restrained. This seems to be the case with the current structure too, as the observed standard deviation is below 4.0 degrees.

Standard deviation of omega values : 1.625

Bump checks

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.

  83 ARG   ( 188-)  A      NH2 <->  286 HOH   (  83 )  A      O      0.55    2.15  INTRA BF
 166 PHE   ( 111-)  B      O   <->  175 ARG   ( 129-)  B      NH1    0.39    2.31  INTRA BF
 279 ARG   ( 252-)  B      C   <->  281 ARG   ( 254-)  B      N      0.33    2.57  INTRA BF
  31 ARG   ( 129-)  A      NH2 <->  133 GLN   ( 241-)  A      OE1    0.32    2.38  INTRA BF
 279 ARG   ( 252-)  B      O   <->  281 ARG   ( 254-)  B      N      0.27    2.43  INTRA BF
 144 ARG   ( 252-)  A      NE  <->  286 HOH   (  73 )  A      O      0.26    2.44  INTRA BF
 100 VAL   ( 208-)  A      CG2 <->  286 HOH   (  77 )  A      O      0.25    2.55  INTRA BF
 130 HIS   ( 238-)  A      ND1 <->  286 HOH   (  55 )  A      O      0.24    2.46  INTRA BL
  83 ARG   ( 188-)  A      NH1 <->  286 HOH   (  82 )  A      O      0.23    2.47  INTRA BF
 265 HIS   ( 238-)  B      ND1 <->  287 HOH   (  28 )  B      O      0.19    2.51  INTRA BF
 211 LYS   ( 179-)  B      NZ  <->  214 GLU   ( 182-)  B      OE2    0.14    2.56  INTRA BF
  79 ARG   ( 184-)  A      NE  <->   90 ILE   ( 198-)  A      CD1    0.13    2.97  INTRA BF
 152 LEU   (  97-)  B      CD2 <->  192 TRP   ( 146-)  B      CE3    0.12    3.08  INTRA BF
  66 VAL   ( 171-)  A      O   <->  104 GLU   ( 212-)  A      N      0.09    2.61  INTRA BL
 230 ASN   ( 203-)  B      CG  <->  231 LYS   ( 204-)  B      N      0.09    2.91  INTRA BL
  56 MET   ( 161-)  A      CG  <->   57 GLY   ( 162-)  A      N      0.09    2.91  INTRA BF
  22 PHE   ( 111-)  A      O   <->   31 ARG   ( 129-)  A      NH1    0.09    2.61  INTRA BF
 175 ARG   ( 129-)  B      O   <->  186 LEU   ( 140-)  B      N      0.08    2.62  INTRA BF
  58 ASP   ( 163-)  A      N   <->   59 ALA   ( 164-)  A      N      0.08    2.52  INTRA BL
  95 ASN   ( 203-)  A      CG  <->   96 LYS   ( 204-)  A      N      0.08    2.92  INTRA BL
   4 LYS   (  93-)  A      O   <->   58 ASP   ( 163-)  A      N      0.08    2.62  INTRA BL
 126 ALA   ( 234-)  A      N   <->  283 GDP   ( 500-)  A      O6     0.08    2.62  INTRA BL
  20 ARG   ( 109-)  A      NH2 <->  286 HOH   (  25 )  A      O      0.07    2.63  INTRA BF
  48 TRP   ( 146-)  A      CH2 <->   54 MET   ( 159-)  A      CE     0.07    3.13  INTRA BF
 182 GLU   ( 136-)  B      CB  <->  279 ARG   ( 252-)  B      NH2    0.06    3.04  INTRA BF
   1 SER   (  90-)  A      CB  <->    3 TYR   (  92-)  A      CZ     0.06    3.14  INTRA BF
 114 ALA   ( 222-)  A      O   <->  118 ASP   ( 226-)  A      N      0.05    2.65  INTRA BL
 249 ALA   ( 222-)  B      O   <->  253 ASP   ( 226-)  B      N      0.05    2.65  INTRA BF
 233 ASP   ( 206-)  B      OD1 <->  285 GDP   ( 500-)  B      N1     0.05    2.65  INTRA BL
  95 ASN   ( 203-)  A      ND2 <->  283 GDP   ( 500-)  A      N7     0.05    2.95  INTRA BL
  79 ARG   ( 184-)  A      CZ  <->   90 ILE   ( 198-)  A      CD1    0.04    3.16  INTRA BF
 103 ARG   ( 211-)  A      NH2 <->  286 HOH   (  34 )  A      O      0.04    2.66  INTRA BL
 159 LYS   ( 104-)  B      NZ  <->  285 GDP   ( 500-)  B      O2B    0.03    2.67  INTRA BL
 238 ARG   ( 211-)  B      NH2 <->  258 GLU   ( 231-)  B      OE1    0.03    2.67  INTRA BL
 148 LYS   (  93-)  B      CD  <->  189 TYR   ( 143-)  B      OH     0.03    2.77  INTRA BF
 101 ARG   ( 209-)  A      N   <->  286 HOH   (  77 )  A      O      0.03    2.67  INTRA BF
 280 LEU   ( 253-)  B      N   <->  281 ARG   ( 254-)  B      N      0.03    2.57  INTRA BF
 195 ASP   ( 163-)  B      N   <->  196 ALA   ( 164-)  B      N      0.02    2.58  INTRA BF
 192 TRP   ( 146-)  B      N   <->  287 HOH   (  80 )  B      O      0.02    2.68  INTRA BF
  20 ARG   ( 109-)  A      O   <->   24 GLY   ( 113-)  A      N      0.02    2.68  INTRA
 211 LYS   ( 179-)  B      NZ  <->  214 GLU   ( 182-)  B      CD     0.02    3.08  INTRA BF
 100 VAL   ( 208-)  A      CG2 <->  101 ARG   ( 209-)  A      N      0.02    2.98  INTRA BF
 197 TYR   ( 165-)  B      CB  <->  225 ILE   ( 198-)  B      CD1    0.02    3.18  INTRA BF
   4 LYS   (  93-)  A      N   <->   58 ASP   ( 163-)  A      OD2    0.01    2.69  INTRA BF
 261 ALA   ( 234-)  B      N   <->  262 ALA   ( 235-)  B      N      0.01    2.59  INTRA BL
 261 ALA   ( 234-)  B      N   <->  285 GDP   ( 500-)  B      O6     0.01    2.69  INTRA BL
 149 VAL   (  94-)  B      CG2 <->  186 LEU   ( 140-)  B      CD2    0.01    3.19  INTRA BF
 113 CYS   ( 221-)  A      SG  <->  117 PHE   ( 225-)  A      CZ     0.01    3.39  INTRA BL

Packing, accessibility and threading

Note: Inside/Outside RMS Z-score plot

The Inside/Outside distribution normality RMS Z-score over a 15 residue window is plotted as function of the residue number. High areas in the plot (above 1.5) indicate unusual inside/outside patterns.

Chain identifier: A

Note: Inside/Outside RMS Z-score plot

Chain identifier: B

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.

 221 ARG   ( 189-)  B      -5.64
 144 ARG   ( 252-)  A      -5.41
 279 ARG   ( 252-)  B      -5.39
  56 MET   ( 161-)  A      -5.11

Note: Quality value plot

The quality value smoothed over a 10 residue window is plotted as function of the residue number. Low areas in the plot (below -2.0) indicate unusual packing.

Chain identifier: A

Note: Quality value plot

The quality value smoothed over a 10 residue window is plotted as function of the residue number. Low areas in the plot (below -2.0) indicate unusual packing.

Chain identifier: B

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.

 101 ARG   ( 209-)  A   -2.95

Note: Second generation quality Z-score plot

The second generation quality Z-score smoothed over a 10 residue window is plotted as function of the residue number. Low areas in the plot (below -1.3) indicate unusual packing.

Chain identifier: A

Note: Second generation quality Z-score plot

Chain identifier: B

Water, ion, and hydrogenbond related checks

Error: Water molecules without hydrogen bonds

The water molecules listed in the table below do not form any hydrogen bonds, neither with the protein or DNA/RNA, nor with other water molecules. This is a strong indication of a refinement problem. The last number on each line is the identifier of the water molecule in the input file.

 287 HOH   (  66 )  B      O

Error: HIS, ASN, GLN side chain flips

Listed here are Histidine, Asparagine or Glutamine residues for which the orientation determined from hydrogen bonding analysis are different from the assignment given in the input. Either they could form energetically more favourable hydrogen bonds if the terminal group was rotated by 180 degrees, or there is no assignment in the input file (atom type 'A') but an assignment could be made. Be aware, though, that if the topology could not be determined for one or more ligands, then this option will make errors.

 171 HIS   ( 125-)  B

Warning: Buried unsatisfied hydrogen bond donors

The buried hydrogen bond donors listed in the table below have a hydrogen atom that is not involved in a hydrogen bond in the optimized hydrogen bond network.

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.

   9 GLY   (  98-)  A      N
  14 GLY   ( 103-)  A      N
  15 LYS   ( 104-)  A      N
  16 SER   ( 105-)  A      N
  17 ALA   ( 106-)  A      N
  47 ILE   ( 145-)  A      N
  57 GLY   ( 162-)  A      N
  65 SER   ( 170-)  A      OG
  79 ARG   ( 184-)  A      NE
  95 ASN   ( 203-)  A      ND2
 127 ALA   ( 235-)  A      N
 153 GLY   (  98-)  B      N
 158 GLY   ( 103-)  B      N
 159 LYS   ( 104-)  B      N
 160 SER   ( 105-)  B      N
 161 ALA   ( 106-)  B      N
 202 SER   ( 170-)  B      OG
 216 ARG   ( 184-)  B      NE
 230 ASN   ( 203-)  B      ND2
 236 ARG   ( 209-)  B      NE
 255 LYS   ( 228-)  B      N

Warning: Buried unsatisfied hydrogen bond acceptors

The buried side-chain hydrogen bond acceptors listed in the table below are not involved in a hydrogen bond in the optimized hydrogen bond network.

Side-chain hydrogen bond acceptors buried inside the protein normally form hydrogen bonds within the protein. If there are any not hydrogen bonded in the optimized hydrogen bond network they will be listed here.

Waters are not listed by this option.

 233 ASP   ( 206-)  B      OD2

Warning: Possible wrong residue type

The residues listed in the table below have a weird environment that cannot be improved by rotamer flips. This can mean one of three things, non of which WHAT CHECK really can do much about. 1) The side chain has actually another rotamer than is present in the PDB file; 2) A counter ion is present in the structure but is not given in the PDB file; 3) The residue actually is another amino acid type. The annotation 'Alt-rotamer' indicates that WHAT CHECK thinks you might want to find an alternate rotamer for this residue. The annotation 'Sym-induced' indicates that WHAT CHECK believes that symmetry contacts might have something to do with the difficulties of this residue's side chain. Determination of these two annotations is difficult, so their absence is less meaningful than their presence. The annotation Ligand-bound indicates that a ligand seems involved with this residue. In nine of ten of these cases this indicates that the ligand is causing the weird situation rather than the residue.

 104 GLU   ( 212-)  A   H-bonding suggests Gln
 233 ASP   ( 206-)  B   H-bonding suggests Asn; Ligand-contact
 239 GLU   ( 212-)  B   H-bonding suggests Gln

Final summary

Note: Summary report for users of a structure

This is an overall summary of the quality of the structure as compared with current reliable structures. This summary is most useful for biologists seeking a good structure to use for modelling calculations.

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 :   1.073
  2nd generation packing quality :   0.413
  Ramachandran plot appearance   :   0.664
  chi-1/chi-2 rotamer normality  :  -1.125
  Backbone conformation          :   1.691

RMS Z-scores, should be close to 1.0:
  Bond lengths                   :   0.372 (tight)
  Bond angles                    :   0.645 (tight)
  Omega angle restraints         :   0.296 (tight)
  Side chain planarity           :   0.249 (tight)
  Improper dihedral distribution :   0.679
  B-factor distribution          :   0.918
  Inside/Outside distribution    :   1.017

Note: Summary report for depositors of a structure

This is an overall summary of the quality of the X-ray structure as compared with structures solved at similar resolutions. This summary can be useful for a crystallographer to see if the structure makes the best possible use of the data. Warning. This table works well for structures solved in the resolution range of the structures in the WHAT IF database, which is presently (summer 2008) mainly 1.1 - 1.3 Angstrom. The further the resolution of your file deviates from this range the more meaningless this table becomes.

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 : 1.80


Structure Z-scores, positive is better than average:

  1st generation packing quality :   1.4
  2nd generation packing quality :  -0.2
  Ramachandran plot appearance   :   0.7
  chi-1/chi-2 rotamer normality  :  -0.8
  Backbone conformation          :   1.5

RMS Z-scores, should be close to 1.0:
  Bond lengths                   :   0.372 (tight)
  Bond angles                    :   0.645 (tight)
  Omega angle restraints         :   0.296 (tight)
  Side chain planarity           :   0.249 (tight)
  Improper dihedral distribution :   0.679
  B-factor distribution          :   0.918
  Inside/Outside distribution    :   1.017
==============

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.