Contacts of the helix formed by residues 221 - 246 (chain B) in PDB entry 1DKF


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 ASP 221 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215B  GLU*     4.6    13.5    -      -       -      +
    218B  VAL*     5.0     3.8    -      -       +      -
    220B  LEU*     1.3    73.1    -      -       -      +
    222B  ILE*     1.3    51.8    +      -       -      +
    223B  ASP*     3.2    12.3    +      -       -      +
    224B  LEU*     2.7    43.4    +      -       +      +
    225B  TRP*     2.7    31.7    +      -       -      +
    299B  ASN*     2.8    30.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 222 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    220B  LEU*     3.7    18.1    +      -       +      +
    221B  ASP*     1.3    72.2    +      -       -      +
    223B  ASP*     1.3    72.1    +      -       -      +
    225B  TRP*     3.4    25.5    -      -       +      +
    226B  ASP*     2.9    39.0    +      -       -      +
    402B  ILE*     4.5    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 223 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    221B  ASP*     3.0     9.2    +      -       -      +
    222B  ILE*     1.3    90.5    -      -       +      +
    224B  LEU*     1.3    64.4    +      -       -      +
    226B  ASP*     3.5    19.8    +      -       -      +
    227B  LYS*     3.6    27.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 224 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    210B  THR*     5.7     8.7    -      -       -      -
    215B  GLU*     6.6     0.2    -      -       +      -
    221B  ASP*     2.7    41.3    +      -       +      +
    223B  ASP*     1.3    69.6    -      -       -      +
    225B  TRP*     1.3    67.0    +      -       -      +
    227B  LYS*     3.0    18.1    +      -       +      +
    228B  PHE*     3.0    23.8    +      -       -      +
    290B  LEU*     5.5     2.7    -      -       +      -
    292B  LEU*     4.1    30.5    -      -       +      -
    296B  GLN*     3.5    39.9    -      -       +      +
    299B  ASN*     4.1     5.2    -      -       +      -
    300B  ALA*     3.9     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 225 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    220B  LEU*     4.1    12.1    -      -       +      -
    221B  ASP      2.7    12.3    +      -       -      +
    222B  ILE*     3.4    26.2    -      -       +      +
    224B  LEU*     1.3    77.3    -      -       -      +
    226B  ASP*     1.3    72.1    +      -       -      +
    228B  PHE*     3.8    22.7    -      +       -      -
    229B  SER*     2.8    47.8    +      -       -      -
    300B  ALA      3.0    35.6    +      -       -      +
    301B  GLY*     4.1     5.6    -      -       -      -
    398B  LEU*     3.7    30.1    -      -       +      -
    402B  ILE*     3.7    32.0    -      -       +      +
    405B  SER*     4.6     7.9    -      -       -      +
    406B  MET*     4.0    17.7    -      -       +      -
    600B  BMS      3.9    20.9    -      +       -      -
----------------------------------------------------------
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Residues in contact with ASP 226 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  ILE*     2.9    28.3    +      -       -      +
    223B  ASP*     3.7    18.7    -      -       -      +
    224B  LEU      3.1     0.6    -      -       -      -
    225B  TRP*     1.3    91.6    +      -       -      +
    227B  LYS*     1.3    62.2    +      -       +      +
    229B  SER*     3.9     4.3    -      -       -      -
    230B  GLU*     3.2    25.3    +      -       -      +
    402B  ILE*     6.0     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 227 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    208B  TYR*     5.7     5.4    -      -       +      +
    210B  THR      4.6    21.3    +      -       -      +
    223B  ASP*     3.6    21.1    +      -       -      +
    224B  LEU*     3.0    17.0    +      -       +      +
    226B  ASP*     1.3    77.8    -      -       +      +
    228B  PHE*     1.3    61.4    +      -       -      +
    230B  GLU*     3.1     8.2    -      -       -      +
    231B  LEU*     2.8    35.6    +      -       +      +
    290B  LEU*     4.4    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 228 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224B  LEU      3.0    15.0    +      -       -      +
    225B  TRP*     3.8    26.2    -      +       -      +
    227B  LYS*     1.3    76.1    -      -       -      +
    229B  SER*     1.3    59.4    +      -       -      +
    231B  LEU*     3.4     7.6    +      -       -      +
    232B  SER*     2.9    42.2    +      -       -      -
    286B  PHE*     3.8    31.6    -      +       +      -
    290B  LEU*     5.6     1.5    -      -       -      +
    292B  LEU*     5.8     2.5    -      -       +      -
    297B  MET*     4.8     1.8    -      -       +      -
    300B  ALA*     3.4    34.1    -      -       +      +
    301B  GLY*     4.5     4.7    -      -       -      -
    302B  PHE*     3.9    21.1    -      +       -      -
    600B  BMS      3.3    52.3    -      +       -      -
----------------------------------------------------------
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Residues in contact with SER 229 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225B  TRP*     2.8    47.2    +      -       -      -
    226B  ASP*     3.9     5.6    -      -       -      -
    228B  PHE*     1.3    74.4    -      -       -      +
    230B  GLU*     1.3    61.1    +      -       -      +
    233B  THR*     3.0    28.6    +      -       -      -
    405B  SER*     5.8     0.5    -      -       -      -
    406B  MET*     4.5     4.5    +      -       -      +
    600B  BMS      3.1    35.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 230 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226B  ASP      3.2    12.6    +      -       -      +
    227B  LYS*     3.1    12.6    -      -       -      +
    229B  SER*     1.3    77.2    -      -       -      +
    231B  LEU*     1.3    68.7    +      -       +      +
    233B  THR*     2.9    19.9    +      -       -      -
    234B  LYS*     3.1    47.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 231 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227B  LYS*     2.8    23.6    +      -       +      +
    228B  PHE*     3.8     4.5    -      -       -      +
    230B  GLU*     1.3    75.4    +      -       +      +
    232B  SER*     1.3    56.9    +      -       -      +
    234B  LYS*     3.3    21.1    +      -       +      +
    235B  CYS*     2.9    23.9    +      -       -      +
    286B  PHE*     3.6    30.3    -      -       +      -
    287B  SER*     5.4     1.1    -      -       -      -
    288B  ASP*     3.8    34.5    -      -       +      +
    290B  LEU*     3.8    23.1    -      -       +      -
    600B  BMS      3.6    33.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 232 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228B  PHE*     2.9    23.9    +      -       -      -
    229B  SER      3.7     1.3    -      -       -      -
    231B  LEU*     1.3    73.4    -      -       -      +
    233B  THR*     1.3    69.2    +      -       -      +
    235B  CYS*     2.8    13.0    +      -       -      +
    236B  ILE*     2.8    18.5    +      -       -      +
    269B  LEU*     5.0     0.4    -      -       -      -
    600B  BMS      3.1    74.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 233 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    229B  SER      3.0    12.9    +      -       -      -
    230B  GLU*     2.9    12.2    +      -       -      -
    232B  SER*     1.3    78.8    -      -       -      +
    234B  LYS*     1.3    64.8    -      -       +      +
    236B  ILE*     3.1     8.1    +      -       -      +
    237B  ILE*     3.1    34.7    +      -       +      +
    407B  PRO*     5.7     3.1    -      -       -      +
    409B  LEU*     4.3    17.2    -      -       +      +
    600B  BMS      3.3    21.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 234 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230B  GLU*     3.1    42.4    +      -       -      +
    231B  LEU*     3.4    22.8    -      -       +      +
    232B  SER      3.1     0.2    -      -       -      -
    233B  THR*     1.3    82.1    -      -       +      +
    235B  CYS*     1.3    56.9    +      -       -      +
    237B  ILE*     3.1    18.0    +      -       +      +
    238B  LYS*     2.9    32.4    +      -       +      +
    288B  ASP*     6.4     1.1    -      -       -      -
    600B  BMS      6.0     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 235 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199B  PHE*     4.4     2.7    -      -       -      -
    231B  LEU      2.9    12.4    +      -       -      +
    232B  SER      2.8    11.4    +      -       -      +
    234B  LYS*     1.3    71.1    -      -       -      +
    236B  ILE*     1.3    55.9    +      -       -      +
    238B  LYS*     3.4     6.2    -      -       -      +
    239B  THR*     2.7    38.7    +      -       -      -
    269B  LEU*     4.0    11.4    -      -       +      -
    272B  ARG*     3.7    32.1    -      -       -      -
    287B  SER*     5.0     2.2    -      -       -      -
    600B  BMS      3.5    41.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 236 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    232B  SER      2.8    26.6    +      -       -      +
    233B  THR*     3.4     7.2    -      -       -      +
    235B  CYS*     1.3    72.7    -      -       -      +
    237B  ILE*     1.3    68.0    +      -       -      +
    239B  THR*     3.1     8.8    +      -       -      -
    240B  VAL*     2.9    23.0    +      -       -      +
    265B  CYS*     4.1    16.6    -      -       +      -
    269B  LEU*     3.5    25.4    -      -       +      -
    409B  LEU*     4.2    11.4    -      -       +      -
    410B  ILE*     3.6    31.2    -      -       +      -
    413B  MET*     4.0    12.8    -      -       +      -
    600B  BMS      3.4    34.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 237 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233B  THR*     3.1    27.9    +      -       +      +
    234B  LYS*     3.2    20.0    -      -       +      +
    236B  ILE*     1.3    77.2    -      -       -      +
    238B  LYS*     1.3    64.3    +      -       -      +
    240B  VAL*     3.2     5.5    +      -       -      +
    241B  GLU*     2.9    45.0    +      -       +      +
    409B  LEU*     4.2     8.5    -      -       +      -
    413B  MET*     3.6    34.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 238 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197B  GLU      4.7     8.7    +      -       -      -
    198B  THR*     3.4    44.5    -      -       -      +
    234B  LYS*     2.9    19.7    +      -       +      +
    235B  CYS*     3.4    11.0    -      -       -      +
    237B  ILE*     1.3    78.9    -      -       -      +
    239B  THR*     1.3    59.6    +      -       -      +
    241B  GLU*     3.0    34.7    +      -       -      +
    242B  PHE*     2.9    23.7    +      -       -      +
    272B  ARG*     4.0     3.4    -      -       -      +
    287B  SER*     6.5     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 239 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    235B  CYS      2.7    25.2    +      -       -      -
    236B  ILE*     3.1     8.9    +      -       -      -
    238B  LYS*     1.3    73.1    -      -       -      +
    240B  VAL*     1.3    57.0    +      -       -      +
    242B  PHE*     3.1    15.0    +      -       +      +
    243B  ALA*     2.9    26.6    +      -       +      +
    261B  LEU*     4.7     8.3    -      -       +      -
    265B  CYS*     4.6    14.6    -      -       -      -
    268B  ILE*     3.7    41.8    -      -       +      +
    269B  LEU*     3.5    17.0    -      -       +      +
    272B  ARG*     3.9     9.5    +      -       -      +
    334B  LEU*     6.3     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 240 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    236B  ILE      2.9    17.4    +      -       -      +
    237B  ILE      3.2     9.2    +      -       -      +
    239B  THR*     1.3    77.7    -      -       -      +
    241B  GLU*     1.3    62.7    +      -       +      +
    243B  ALA*     3.3     3.5    +      -       -      +
    244B  LYS*     3.1    30.2    +      -       +      +
    261B  LEU*     3.5    27.8    -      -       +      +
    265B  CYS*     5.4     0.9    -      -       -      -
    410B  ILE*     4.3    14.6    -      -       +      -
    413B  MET*     3.7    33.2    -      -       +      -
    414B  LEU*     3.9    26.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 241 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198B  THR*     4.1     9.8    -      -       +      +
    237B  ILE*     2.9    34.4    +      -       +      +
    238B  LYS*     3.0    40.7    +      -       -      +
    240B  VAL*     1.3    75.7    -      -       +      +
    242B  PHE*     1.3    65.2    +      -       -      +
    244B  LYS*     3.4     8.3    +      -       -      +
    245B  GLN*     3.1    34.3    +      -       +      +
    413B  MET*     5.9     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 242 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191B  VAL*     4.1     3.4    -      -       +      -
    194B  ALA*     3.6    27.6    -      -       +      -
    195B  HIS*     3.6    27.4    -      -       +      -
    198B  THR*     3.4    21.5    -      -       -      +
    238B  LYS      2.9     9.0    +      -       -      +
    239B  THR*     3.1    18.4    +      -       +      +
    241B  GLU*     1.3    77.5    -      -       -      +
    243B  ALA*     1.3    60.3    +      -       +      +
    245B  GLN*     2.8    28.2    +      -       -      +
    246B  LEU*     3.2    35.4    +      -       +      +
    268B  ILE*     5.8     3.4    -      -       +      -
    272B  ARG*     3.8    13.5    -      -       -      +
    327B  GLY*     3.4    24.7    -      -       -      -
    330B  SER*     3.8    23.3    -      -       -      -
    331B  ALA      4.2     2.9    -      -       -      -
    334B  LEU*     5.1     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 243 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239B  THR      2.9    11.7    +      -       -      +
    240B  VAL      3.6     8.1    -      -       -      +
    242B  PHE*     1.3    76.7    -      -       +      +
    244B  LYS*     1.3    58.6    +      -       -      +
    246B  LEU*     2.9    29.0    +      -       -      +
    249B  PHE*     3.1    37.9    -      -       +      +
    261B  LEU*     3.9    11.0    -      -       +      -
    334B  LEU*     3.6    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 244 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240B  VAL*     3.1    22.5    +      -       +      +
    241B  GLU*     3.6    13.0    -      -       -      +
    242B  PHE      3.2     0.2    -      -       -      -
    243B  ALA*     1.3    75.8    -      -       -      +
    245B  GLN*     1.3    70.4    +      -       -      +
    246B  LEU      3.4     5.0    +      -       -      +
    249B  PHE*     4.0     9.6    -      -       +      +
    250B  THR*     4.1    31.6    +      -       +      +
    257B  GLN*     5.2     2.9    -      -       -      +
    413B  MET*     4.3     7.1    +      -       -      +
    414B  LEU*     3.5    42.5    +      -       +      +
    416B  ASN*     4.1     9.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 245 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    190B  LYS*     5.6     4.5    -      -       -      +
    194B  ALA*     3.6    29.0    -      -       +      +
    197B  GLU*     5.2     9.3    -      -       +      +
    198B  THR*     5.4     3.1    -      -       +      -
    241B  GLU*     3.1    29.0    +      -       +      +
    242B  PHE*     2.8    13.2    +      -       -      +
    244B  LYS*     1.3    87.1    +      -       -      +
    246B  LEU*     1.3    62.3    +      -       -      +
    247B  PRO*     3.4     8.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 246 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191B  VAL*     4.2    18.6    -      -       +      -
    194B  ALA*     4.7     3.6    -      -       +      -
    242B  PHE*     3.5    44.6    -      -       +      +
    243B  ALA*     2.9    16.3    +      -       -      +
    244B  LYS      3.9     3.8    -      -       -      +
    245B  GLN*     1.3    78.2    -      -       -      +
    247B  PRO*     1.4    65.5    -      -       +      +
    248B  GLY      3.2     0.7    +      -       -      -
    249B  PHE*     2.9    30.3    +      -       +      +
    250B  THR*     4.5     1.4    +      -       -      -
    331B  ALA*     3.9    22.7    -      -       +      -
    334B  LEU*     3.4    33.2    -      -       +      -
    335B  ILE*     4.1    12.8    -      -       +      -
    355B  LEU*     5.7     1.6    -      -       +      -
----------------------------------------------------------
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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).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il