Contacts of the helix formed by residues 45 - 71 (chain A) in PDB entry 2X6B


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with SER 45 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  THR      3.9     0.2    +      -       -      -
     44A  VAL*     1.3    75.9    -      -       -      +
     46A  TRP*     1.3    67.3    +      -       -      +
     47A  PRO*     3.2    11.7    -      -       -      -
     48A  VAL*     3.0    38.5    +      -       -      +
     49A  PHE*     3.2     8.8    +      -       -      +
    134A  ARG*     4.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  VAL      3.6     0.8    +      -       -      -
     45A  SER*     1.3    70.9    -      -       -      +
     47A  PRO*     1.3    69.3    -      -       +      +
     49A  PHE*     3.6    17.6    +      +       -      +
     50A  ILE*     3.4    34.9    +      -       +      +
    131A  ILE*     4.6     7.6    -      -       +      -
    134A  ARG*     3.4    65.0    -      -       +      +
    135A  PHE*     3.5    35.7    -      +       -      -
    137A  ARG*     5.1     1.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  SER*     3.3    14.1    -      -       -      -
     46A  TRP*     1.3    91.1    -      -       +      +
     48A  VAL*     1.3    63.3    +      -       +      +
     49A  PHE      3.0     2.1    +      -       -      -
     50A  ILE*     3.3     8.9    +      -       +      +
     51A  THR*     2.9    33.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  VAL*     4.0    24.5    -      -       +      -
     45A  SER*     3.0    28.3    +      -       -      +
     47A  PRO*     1.3    80.9    -      -       +      +
     49A  PHE*     1.3    56.1    +      -       -      +
     51A  THR*     3.3     9.3    -      -       +      -
     52A  LEU*     2.9    38.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  LEU*     3.9    20.9    -      -       +      -
     44A  VAL*     4.4     5.1    -      -       +      +
     45A  SER      3.2     5.1    +      -       -      +
     46A  TRP*     3.6    21.1    -      +       +      +
     47A  PRO      3.0     0.6    -      -       -      -
     48A  VAL*     1.3    74.6    -      -       -      +
     50A  ILE*     1.3    71.1    +      -       +      +
     51A  THR      2.8     5.0    +      -       -      -
     52A  LEU*     3.0     6.8    +      -       +      +
     53A  ILE*     3.0    44.4    +      -       +      +
    130A  LEU*     3.9    31.9    -      -       +      -
    131A  ILE*     3.2    36.3    -      -       +      -
    134A  ARG*     3.2    49.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  TRP*     3.4    20.1    +      -       +      +
     47A  PRO*     3.3     9.3    +      -       +      +
     49A  PHE*     1.3    86.6    -      -       +      +
     51A  THR*     1.3    55.2    +      -       -      +
     53A  ILE*     4.3     4.2    -      -       -      +
     54A  THR*     2.7    46.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  PRO*     2.9    16.6    +      -       -      +
     48A  VAL*     3.3    16.0    -      -       +      +
     49A  PHE      2.8     1.6    -      -       -      -
     50A  ILE*     1.3    75.8    -      -       -      +
     52A  LEU*     1.3    71.5    +      -       +      +
     54A  THR*     3.6     5.1    -      -       -      +
     55A  GLY*     2.8    21.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  LEU*     3.9    27.8    -      -       +      -
     44A  VAL*     4.9    11.2    -      -       +      -
     48A  VAL*     2.9    35.2    +      -       +      +
     49A  PHE*     3.0     8.0    +      -       +      +
     51A  THR*     1.3    75.2    -      -       +      +
     53A  ILE*     1.3    60.2    +      -       +      +
     55A  GLY*     3.0     3.9    +      -       -      -
     56A  LEU*     2.8    27.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  PHE*     3.0    46.3    +      -       +      +
     50A  ILE*     4.3     4.0    -      -       -      +
     52A  LEU*     1.3    74.8    -      -       +      +
     54A  THR*     1.3    73.0    +      -       -      +
     55A  GLY      2.7     2.9    +      -       -      -
     56A  LEU*     2.9    19.8    +      -       +      +
     57A  TYR*     3.0    15.9    +      -       +      +
    127A  ALA*     3.8    32.3    -      -       +      -
    130A  LEU*     6.0     2.5    -      -       +      -
    131A  ILE*     4.3     4.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  ILE*     2.7    33.3    +      -       -      +
     51A  THR*     3.6     6.5    -      -       -      +
     53A  ILE*     1.3    81.4    -      -       -      +
     55A  GLY*     1.3    59.5    +      -       -      +
     57A  TYR*     3.6     7.8    -      -       -      +
     58A  LEU*     3.1    36.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  THR      2.8    14.2    +      -       -      -
     52A  LEU*     3.2     5.2    -      -       -      -
     53A  ILE      2.7     2.6    +      -       -      -
     54A  THR*     1.3    76.3    -      -       -      +
     56A  LEU*     1.3    65.5    +      -       -      -
     58A  LEU*     2.8    23.4    +      -       -      +
     59A  VAL*     3.1    16.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  LEU      2.8    15.1    +      -       -      +
     53A  ILE*     2.9    12.0    +      -       +      +
     55A  GLY*     1.3    68.9    -      -       -      -
     57A  TYR*     1.3    66.7    +      -       -      +
     59A  VAL*     3.0    22.5    +      -       +      +
     60A  THR*     3.1    33.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  ILE*     3.0    13.0    +      -       +      +
     54A  THR*     3.6    14.6    -      -       -      +
     56A  LEU*     1.3    76.1    -      -       -      +
     58A  LEU*     1.3    78.0    +      -       +      +
     60A  THR*     2.7    23.2    +      -       -      -
     61A  ASN*     3.3    23.8    +      -       -      -
     87A  PHE*     5.9     0.4    -      +       -      -
     91A  VAL*     3.6    32.4    +      -       +      +
     94A  MET*     3.5    24.4    -      -       +      +
     95A  ALA*     4.1    13.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  THR*     3.1    31.0    -      -       +      +
     55A  GLY*     2.8    16.2    +      -       -      +
     57A  TYR*     1.3    91.1    -      -       +      +
     59A  VAL*     1.3    57.7    +      -       +      +
     62A  ALA*     2.9    25.3    +      -       -      +
     87A  PHE*     3.1    33.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  GLY      3.1    15.2    +      -       -      +
     56A  LEU*     3.0    17.4    +      -       +      +
     58A  LEU*     1.3    77.3    -      -       +      +
     60A  THR*     1.3    58.8    +      -       +      +
     62A  ALA*     3.2    10.1    +      -       +      +
     63A  LEU*     2.8    42.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  LEU*     3.1    31.5    +      -       +      +
     57A  TYR*     2.7    20.1    +      -       -      -
     59A  VAL*     1.3    75.7    -      -       +      +
     61A  ASN*     1.3    62.5    +      -       -      +
     63A  LEU*     2.8    16.0    +      -       +      +
     64A  PHE*     2.6    52.5    +      -       -      -
     94A  MET*     3.7    13.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  TYR*     3.3    28.9    +      -       -      +
     60A  THR*     1.3    79.1    +      -       -      +
     62A  ALA*     1.3    58.7    +      -       -      +
     64A  PHE      3.9     0.2    -      -       -      -
     65A  ALA*     2.9    31.4    +      -       -      +
     87A  PHE*     3.2    23.6    -      -       +      -
     90A  SER*     3.0    28.3    +      -       -      +
     91A  VAL*     3.3    32.3    -      -       -      +
     94A  MET*     3.0    25.2    -      -       -      +
    116A  GLU*     3.2     7.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58A  LEU      2.9    15.9    +      -       -      +
     59A  VAL*     3.2    16.4    -      -       +      +
     61A  ASN*     1.3    75.5    -      -       -      +
     63A  LEU*     1.3    59.5    +      -       +      +
     66A  LEU*     3.0    28.1    +      -       -      +
     83A  PHE*     3.4    15.6    -      -       +      -
     87A  PHE*     3.0    16.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  VAL*     2.8    31.6    +      -       +      +
     60A  THR*     2.8    19.1    +      -       +      +
     62A  ALA*     1.3    76.5    -      -       +      +
     64A  PHE*     1.3    62.3    +      -       +      +
     66A  LEU*     3.0    24.2    -      -       +      +
     67A  ALA*     2.8    24.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  THR*     2.6    40.2    +      -       -      -
     61A  ASN*     4.7     0.7    -      -       -      -
     63A  LEU*     1.3    70.5    -      -       +      +
     65A  ALA*     1.3    59.5    +      -       -      +
     66A  LEU      2.8     1.3    -      -       -      -
     67A  ALA*     2.5    31.2    +      -       +      +
     68A  TYR*     2.9    27.8    +      +       +      -
     90A  SER*     3.3    15.7    -      -       -      +
     94A  MET*     4.7     4.3    -      -       -      -
    112A  LEU*     4.2     9.9    -      -       +      -
    115A  LEU*     4.4    15.5    -      -       +      -
    116A  GLU*     3.4    62.8    -      -       +      +
    119A  CYS*     4.2    18.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61A  ASN      2.9    22.9    +      -       -      +
     64A  PHE*     1.3    76.4    -      -       -      +
     66A  LEU*     1.3    59.9    +      -       -      +
     68A  TYR*     4.2     1.8    -      -       -      -
     69A  LEU*     3.3    17.0    +      -       -      +
     83A  PHE*     3.6    18.8    -      -       +      -
     86A  ALA*     3.1    31.7    -      -       +      +
     87A  PHE*     3.2    30.7    -      -       -      +
     90A  SER*     3.9     1.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  ALA      3.0    16.2    +      -       -      +
     63A  LEU*     3.0    29.3    +      -       +      +
     64A  PHE      2.8     0.6    -      -       -      -
     65A  ALA*     1.3    80.8    -      -       -      +
     67A  ALA*     1.3    55.8    +      -       -      +
     69A  LEU*     4.0     7.6    -      -       +      +
     70A  ALA*     3.1    24.4    +      -       -      +
     83A  PHE*     4.4    13.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 67 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  LEU      2.8     9.8    +      -       -      +
     64A  PHE*     2.5    28.8    +      -       +      +
     66A  LEU*     1.3    69.8    -      -       -      +
     68A  TYR*     1.3    57.7    +      -       +      +
     69A  LEU      3.0     5.2    -      -       -      -
     70A  ALA*     2.8    28.9    +      -       -      +
     71A  CYS*     3.2    12.7    -      -       -      -
    112A  LEU*     4.3    20.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 68 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  PHE*     2.9    41.0    +      +       +      +
     65A  ALA*     4.1     7.9    -      -       -      +
     67A  ALA*     1.3    71.8    -      -       +      +
     69A  LEU*     1.3    60.1    +      -       -      +
     71A  CYS*     2.9    23.0    -      -       -      +
     72A  GLY      3.0    11.6    -      -       -      +
     74A  VAL*     4.2     6.7    +      -       +      +
     75A  ILE*     4.3    19.1    -      -       +      -
     86A  ALA*     4.6     7.6    -      -       +      -
     89A  PHE*     3.7    35.0    -      +       -      -
     90A  SER*     4.9     1.6    -      -       -      -
     93A  THR*     4.1     2.5    -      -       +      +
    109A  ALA*     4.0    18.6    -      -       +      -
    112A  LEU*     3.5    33.8    +      -       +      -
    113A  VAL*     3.6    23.3    +      -       +      +
    116A  GLU*     2.7    29.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 69 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  ALA      3.3    18.4    +      -       -      +
     66A  LEU*     4.2     9.2    -      -       +      +
     67A  ALA      3.0     0.6    -      -       -      -
     68A  TYR*     1.3    80.3    -      -       +      +
     70A  ALA*     1.3    60.8    +      -       -      +
     71A  CYS      2.7    16.6    -      -       -      +
     72A  GLY      5.5     1.6    -      -       -      +
     73A  ASP*     5.6     6.1    -      -       -      +
     75A  ILE*     6.2     1.8    -      -       +      -
     79A  ARG      5.3     1.6    -      -       -      +
     80A  PRO*     5.7     0.2    -      -       +      -
     81A  GLY*     3.8    31.4    -      -       -      +
     82A  SER      3.8     7.4    -      -       -      +
     83A  PHE*     3.4    43.1    -      -       +      +
     86A  ALA*     3.9     8.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 70 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  LEU      3.1    16.8    +      -       -      +
     67A  ALA*     2.8    17.2    +      -       -      +
     69A  LEU*     1.3    77.9    -      -       -      +
     71A  CYS*     1.3    55.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 71 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  ALA      3.2    17.5    -      -       -      -
     68A  TYR*     2.9    18.6    -      -       -      +
     69A  LEU*     2.7    16.1    -      -       -      +
     70A  ALA*     1.3    77.1    -      -       -      +
     72A  GLY*     1.3    70.4    +      -       -      +
     74A  VAL*     3.8    18.8    -      -       +      -
    108A  LEU*     5.2    17.9    -      -       +      -
    109A  ALA      6.0     0.2    -      -       -      -
    112A  LEU*     4.1    16.2    -      -       -      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

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