Contacts of the helix formed by residues 218 - 245 (chain A) in PDB entry 3PWH


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 GLY 218 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    214A  GLN*     4.3     4.2    +      -       -      +
    216A  LEU*     3.7    15.4    -      -       -      +
    217A  PRO*     1.3    83.7    -      -       -      +
    219A  GLU*     1.3    59.8    +      -       -      +
    220A  ARG*     3.1    11.1    +      -       -      -
    221A  ALA*     3.3    16.5    +      -       -      +
    222A  ARG*     3.7    10.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 219 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    217A  PRO*     3.7    24.2    -      -       +      +
    218A  GLY*     1.3    73.8    -      -       -      +
    220A  ARG*     1.3    62.6    +      -       -      +
    221A  ALA      3.3     0.2    -      -       -      -
    222A  ARG*     3.5    41.9    +      -       -      +
    223A  SER*     2.8    42.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 220 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    218A  GLY*     3.1     3.1    -      -       -      -
    219A  GLU*     1.3    81.9    +      -       -      +
    221A  ALA*     1.3    61.0    +      -       -      +
    223A  SER*     4.3     9.1    +      -       -      -
    224A  THR*     2.7    38.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 221 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  MET*     3.6    22.0    -      -       -      -
    214A  GLN*     6.0     0.9    -      -       -      +
    218A  GLY*     3.3    10.5    +      -       -      +
    219A  GLU      3.3     0.2    -      -       -      -
    220A  ARG*     1.3    77.5    -      -       -      +
    222A  ARG*     1.3    61.2    +      -       -      +
    224A  THR*     3.9     2.7    -      -       -      -
    225A  LEU*     2.8    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 222 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    208A  LEU*     5.0     5.4    +      -       +      +
    211A  MET*     2.8    56.3    +      -       +      +
    212A  GLU*     3.8    16.4    +      -       -      +
    214A  GLN*     3.9     9.3    -      -       -      +
    217A  PRO      5.0     0.2    -      -       -      -
    218A  GLY      3.7     6.9    +      -       -      +
    219A  GLU*     3.4    40.8    +      -       -      +
    221A  ALA*     1.3    79.2    -      -       -      +
    223A  SER*     1.3    57.4    +      -       -      +
    225A  LEU*     3.2     1.8    +      -       -      +
    226A  GLN*     2.8    52.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 223 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219A  GLU*     2.8    31.8    +      -       -      +
    220A  ARG*     4.3    12.7    +      -       -      -
    222A  ARG*     1.3    72.9    -      -       -      +
    224A  THR*     1.3    63.7    +      -       -      +
    226A  GLN*     3.5     8.8    +      -       -      +
    227A  LYS*     3.2    30.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 224 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    220A  ARG*     2.7    29.5    +      -       -      -
    221A  ALA*     3.9     3.6    -      -       -      -
    223A  SER*     1.3    76.1    -      -       -      +
    225A  LEU*     1.3    59.5    +      -       -      +
    227A  LYS*     3.1     8.2    +      -       -      +
    228A  GLU*     2.9    43.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 225 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  ILE*     4.2    30.1    -      -       +      +
    109A  PRO*     6.4     1.6    -      -       +      -
    204A  ALA      4.0     4.9    -      -       -      +
    207A  GLN*     3.4    35.7    -      -       +      -
    208A  LEU*     3.6    14.8    -      -       +      -
    211A  MET*     3.5    20.9    -      -       +      -
    221A  ALA      2.8    23.0    +      -       -      +
    222A  ARG      3.6     2.9    -      -       -      +
    224A  THR*     1.3    74.6    -      -       -      +
    226A  GLN*     1.3    52.0    +      -       -      +
    228A  GLU*     2.9    12.5    +      -       +      +
    229A  VAL*     2.7    44.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 226 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    208A  LEU*     4.4    25.0    -      -       +      +
    222A  ARG*     2.8    40.3    +      -       -      +
    223A  SER*     3.9     8.2    -      -       -      +
    225A  LEU*     1.3    71.5    -      -       -      +
    227A  LYS*     1.3    61.5    +      -       +      +
    229A  VAL*     3.8     9.8    -      -       -      +
    230A  HIS*     3.0    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 227 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223A  SER*     3.2    15.6    +      -       -      +
    224A  THR*     3.1    10.2    +      -       -      +
    225A  LEU      3.0     0.6    -      -       -      -
    226A  GLN*     1.3    83.9    -      -       -      +
    228A  GLU*     1.3    61.1    +      -       -      +
    229A  VAL      3.1     1.1    -      -       -      -
    230A  HIS*     3.5    21.4    +      -       +      +
    231A  ALA*     2.9    29.1    +      -       -      +
    293A  ARG*     3.3    41.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 228 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  ARG*     3.3    35.1    +      -       -      -
    105A  ALA*     4.0    13.3    -      -       +      +
    106A  ILE*     3.7    21.2    -      -       +      +
    224A  THR*     2.9    34.2    +      -       +      +
    225A  LEU*     2.9    13.1    +      -       +      +
    227A  LYS*     1.3    75.9    -      -       -      +
    229A  VAL*     1.3    58.2    +      -       -      +
    231A  ALA*     3.5     4.6    +      -       -      +
    232A  ALA*     3.0    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 229 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  ILE*     3.8    14.6    -      -       +      -
    200A  ILE*     6.4     0.4    -      -       +      -
    201A  PHE*     4.2    22.7    -      -       +      -
    204A  ALA*     3.8    28.5    -      -       +      -
    205A  ARG*     5.0    10.3    -      -       -      +
    208A  LEU*     6.1     4.5    -      -       +      -
    225A  LEU*     2.7    29.4    +      -       +      +
    226A  GLN*     3.8     9.0    -      -       -      +
    228A  GLU*     1.3    75.4    -      -       -      +
    230A  HIS*     1.3    55.6    +      -       -      +
    231A  ALA      3.2     0.2    -      -       -      -
    232A  ALA*     3.1     1.5    +      -       -      +
    233A  LYS*     2.7    36.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 230 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  GLN      3.0    20.5    +      -       -      +
    227A  LYS*     3.2    26.2    +      -       +      +
    229A  VAL*     1.3    76.5    -      -       -      +
    231A  ALA*     1.3    54.8    +      -       -      +
    233A  LYS*     4.5     2.5    -      -       -      -
    234A  SER*     2.8    38.7    +      -       -      -
    291A  ARG*     2.9    59.1    +      -       -      +
    292A  ILE*     4.9     4.9    -      -       +      -
    293A  ARG*     5.1    11.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 231 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  ARG*     3.3    32.0    -      -       -      +
    227A  LYS      2.9    16.1    +      -       -      +
    228A  GLU      3.8     0.9    -      -       -      +
    229A  VAL      3.2     0.2    -      -       -      -
    230A  HIS*     1.3    76.7    -      -       +      +
    232A  ALA*     1.3    60.5    +      -       -      +
    234A  SER*     3.5     6.6    +      -       -      -
    235A  ALA*     2.9    27.7    +      -       -      +
    292A  ILE*     5.2     7.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 232 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  ARG*     3.8    28.0    -      -       +      +
    106A  ILE*     3.9    15.5    -      -       +      -
    197A  TYR*     3.3    11.6    -      -       -      -
    200A  ILE*     4.1    15.3    -      -       +      -
    201A  PHE*     3.9     5.4    -      -       +      -
    228A  GLU      3.0    17.3    +      -       -      +
    229A  VAL*     3.5     4.9    -      -       -      +
    231A  ALA*     1.3    74.8    -      -       -      +
    233A  LYS*     1.3    60.7    +      -       -      +
    235A  ALA*     3.1     1.6    +      -       -      +
    236A  ALA      2.8    22.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 233 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201A  PHE*     3.3    26.4    -      -       +      -
    205A  ARG*     6.3     0.7    -      -       -      +
    229A  VAL*     2.7    23.4    +      -       +      +
    230A  HIS*     3.8     1.8    -      -       -      +
    232A  ALA*     1.3    70.9    -      -       -      +
    234A  SER*     1.3    64.3    +      -       -      +
    236A  ALA*     3.0     6.2    +      -       +      +
    237A  ILE*     2.9    38.3    +      -       +      +
    291A  ARG*     3.5    31.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 234 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  HIS*     2.8    29.2    +      -       -      -
    231A  ALA*     3.7     5.4    -      -       -      -
    232A  ALA      3.3     0.2    -      -       -      -
    233A  LYS*     1.3    75.8    -      -       -      +
    235A  ALA*     1.3    59.2    +      -       -      +
    237A  ILE*     3.4     7.9    +      -       -      +
    238A  ILE*     3.0    29.4    +      -       -      +
    287A  ILE*     4.4     1.7    -      -       -      +
    288A  TYR*     6.6     0.4    -      -       -      -
    291A  ARG*     2.8    44.2    +      -       -      +
    292A  ILE*     4.0    13.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 235 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  LEU*     5.8     0.3    -      -       -      +
     98A  ILE*     3.8    24.7    -      -       +      -
    102A  ARG*     4.3     4.0    -      -       +      -
    197A  TYR*     3.2    20.4    +      -       +      +
    231A  ALA      2.9    16.1    +      -       -      +
    232A  ALA*     3.3    12.1    -      -       -      +
    233A  LYS      3.1     0.2    -      -       -      -
    234A  SER*     1.3    75.4    -      -       -      +
    236A  ALA*     1.3    64.1    +      -       -      +
    238A  ILE*     3.1    22.7    +      -       +      +
    239A  ALA*     3.1    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 236 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197A  TYR*     3.4    37.6    +      -       +      -
    201A  PHE*     4.5     6.1    -      -       +      -
    232A  ALA      2.8     7.6    +      -       -      +
    233A  LYS*     3.0    13.7    +      -       +      +
    235A  ALA*     1.3    76.9    -      -       -      +
    237A  ILE*     1.3    59.2    +      -       +      +
    239A  ALA*     3.5     1.8    +      -       -      +
    240A  GLY*     2.9    26.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 237 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233A  LYS*     2.9    27.1    +      -       +      +
    234A  SER*     3.7     6.5    -      -       -      +
    235A  ALA      3.2     0.2    -      -       -      -
    236A  ALA*     1.3    77.2    -      -       +      +
    238A  ILE*     1.3    60.4    -      -       -      +
    240A  GLY*     3.9     1.7    -      -       -      +
    241A  LEU*     3.2    32.2    +      -       +      +
    287A  ILE*     3.5    19.7    -      -       +      -
    291A  ARG*     3.7    39.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 238 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  VAL*     6.2     0.4    -      -       +      -
     48A  LEU*     4.2     4.9    -      -       +      -
     95A  LEU*     4.0    21.7    -      -       +      +
     98A  ILE*     5.6     7.2    -      -       +      -
    234A  SER*     3.0    20.0    -      -       -      +
    235A  ALA*     3.1    16.7    +      -       +      +
    237A  ILE*     1.3    76.4    -      -       -      +
    239A  ALA*     1.3    65.7    +      -       -      +
    241A  LEU*     3.3    13.8    +      -       -      +
    242A  PHE*     3.4    10.6    +      -       -      +
    280A  ASN*     4.9     1.4    +      -       -      -
    284A  ASN*     3.6    27.8    -      -       -      +
    287A  ILE*     4.0    19.3    -      -       +      -
    288A  TYR*     3.3    35.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 239 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  LEU*     4.0    31.4    -      -       +      +
    190A  LEU*     4.6     6.0    -      -       +      +
    193A  MET*     4.5    14.4    -      -       +      -
    197A  TYR*     4.5    17.0    -      -       +      +
    235A  ALA      3.1    10.3    +      -       -      +
    236A  ALA      4.1     2.9    -      -       -      +
    238A  ILE*     1.3    79.2    -      -       -      +
    240A  GLY*     1.3    62.9    +      -       -      +
    242A  PHE*     3.3    16.1    +      -       -      +
    243A  ALA*     3.4     9.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 240 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    236A  ALA      2.9    18.7    +      -       -      -
    237A  ILE*     4.1     2.2    -      -       -      -
    238A  ILE      3.2     0.2    -      -       -      -
    239A  ALA*     1.3    78.4    -      -       -      +
    241A  LEU*     1.3    62.7    +      -       -      +
    243A  ALA*     3.6     5.4    +      -       -      +
    244A  LEU*     3.1    24.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 241 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    237A  ILE*     3.2    23.4    +      -       +      +
    238A  ILE*     3.3     9.0    +      -       -      +
    240A  GLY*     1.3    73.6    -      -       -      +
    242A  PHE*     1.3    60.8    +      -       -      +
    244A  LEU*     3.6    21.4    -      -       +      -
    245A  CYS*     2.9    41.0    +      -       -      -
    280A  ASN*     3.6    11.2    -      -       -      +
    283A  VAL*     3.7    33.7    -      -       +      -
    284A  ASN*     5.4     0.2    -      -       -      +
    287A  ILE*     4.1    17.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 242 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  LEU*     6.0     0.9    -      -       +      -
     88A  ALA*     3.8    13.9    -      -       +      -
     91A  SER*     4.0    21.1    -      -       -      -
     92A  ILE*     3.3    34.5    -      -       +      -
     95A  LEU*     3.6    26.7    -      -       +      -
    186A  VAL*     4.8    10.8    -      -       +      -
    190A  LEU*     4.4    10.3    -      -       +      -
    238A  ILE      3.4     5.0    +      -       -      +
    239A  ALA      3.3    10.9    +      -       -      +
    240A  GLY      3.2     0.4    -      -       -      -
    241A  LEU*     1.3    76.9    -      -       -      +
    243A  ALA*     1.3    63.2    +      -       -      +
    245A  CYS      2.8    17.2    +      -       -      -
    246A  TRP*     2.9    53.8    +      +       +      -
    280A  ASN*     2.9    29.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 243 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    190A  LEU*     3.7    33.9    -      -       +      -
    239A  ALA      3.4     5.0    +      -       -      +
    240A  GLY*     4.0     7.4    -      -       -      +
    242A  PHE*     1.3    84.8    -      -       -      +
    244A  LEU*     1.3    57.6    +      -       -      +
    246A  TRP*     4.8     1.6    -      -       -      -
    247A  LEU*     2.9    50.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 244 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240A  GLY      3.1    19.8    +      -       -      +
    241A  LEU*     3.6    25.6    -      -       +      +
    242A  PHE      3.1     0.2    -      -       -      -
    243A  ALA*     1.3    76.5    -      -       -      +
    245A  CYS*     1.3    61.6    +      -       -      +
    246A  TRP      3.5     0.2    -      -       -      -
    247A  LEU*     5.3     2.7    -      -       -      -
    248A  PRO*     3.8    10.6    -      -       +      +
    276A  LEU*     3.7    13.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 245 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    241A  LEU*     2.9    29.9    +      -       -      +
    242A  PHE      2.8     5.3    +      -       -      +
    244A  LEU*     1.3    87.2    -      -       -      +
    246A  TRP*     1.3    59.1    +      -       -      +
    248A  PRO*     4.4     0.2    -      -       -      -
    273A  ALA      5.2     0.9    -      -       -      +
    276A  LEU*     3.6    39.2    -      -       -      +
    277A  ALA*     3.2    27.5    +      -       -      +
    279A  THR*     5.3     4.3    -      -       -      -
    280A  ASN*     3.8    24.5    -      -       +      -
    283A  VAL*     5.7     5.4    -      -       -      -
----------------------------------------------------------
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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