Contacts of the helix formed by residues 149 - 174 (chain F) in PDB entry 3IFS


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 THR 149 (chain F).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    312E  HIS*     3.8    20.6    -      -       +      +
     82F  ILE*     3.9     7.0    -      -       +      -
    144F  SER*     4.0     8.9    +      -       -      -
    146F  SER*     3.6     9.3    +      -       -      -
    147F  GLY      3.7     0.8    -      -       -      -
    148F  THR*     1.3    75.8    +      -       -      +
    150F  THR*     1.3    68.5    +      -       -      +
    151F  GLU*     3.8    14.8    -      -       -      +
    152F  PRO*     3.4    19.3    -      -       +      +
    153F  ALA*     3.0    23.2    +      -       -      +
    426F  LYS*     5.5     7.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 150 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    351E  LEU*     4.5    17.5    -      -       +      +
    354E  LEU*     5.7     2.2    -      -       +      -
    362E  VAL*     4.2    24.5    -      -       +      -
    121F  ILE*     5.1     1.1    -      -       +      -
    148F  THR      3.0     7.4    +      -       -      -
    149F  THR*     1.3    73.6    -      -       -      +
    151F  GLU*     1.3    75.8    +      -       +      +
    153F  ALA*     3.8     2.4    -      -       -      +
    154F  LEU*     3.0    29.6    +      -       +      +
    429F  MSE      3.4    30.6    -      -       +      +
    430F  PHE*     3.8    14.9    -      -       -      -
    433F  LEU*     5.2     6.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 151 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    308E  SER*     2.7    34.4    +      -       -      +
    312E  HIS*     2.9    25.4    +      -       -      -
     82F  ILE*     3.4    12.5    -      -       +      +
    118F  GLY*     3.3    17.9    -      -       -      +
    120F  ASN      3.9    12.2    -      -       -      +
    121F  ILE*     3.4    24.4    -      -       +      +
    149F  THR*     3.8    12.1    -      -       -      +
    150F  THR*     1.3    81.7    +      -       -      +
    152F  PRO*     1.3    64.2    -      -       +      +
    154F  LEU*     3.8     5.3    -      -       -      +
    155F  ALA*     3.1    23.2    +      -       -      +
    425F  TYR*     4.4     5.3    +      -       -      -
    429F  MSE      5.6     4.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 152 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80F  VAL*     3.6    10.6    -      -       +      +
     81F  GLY*     4.0    18.2    -      -       -      -
     82F  ILE*     3.7    22.9    -      -       +      +
    118F  GLY*     3.5    17.5    -      -       -      +
    142F  VAL*     5.7     2.5    -      -       +      -
    143F  ILE      4.9     4.3    -      -       -      +
    144F  SER*     4.8    13.0    -      -       -      +
    149F  THR*     3.4    24.7    -      -       +      +
    151F  GLU*     1.3    96.2    -      -       +      +
    153F  ALA*     1.3    57.1    +      -       -      +
    156F  PHE*     2.8    33.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 153 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    349E  ASP*     4.0    14.4    -      -       +      +
    351E  LEU*     4.0    15.9    -      -       +      -
    144F  SER*     6.2     0.2    -      -       -      -
    147F  GLY*     3.5    25.8    -      -       -      +
    148F  THR*     4.2     4.0    -      -       -      +
    149F  THR      3.0    22.9    +      -       -      +
    150F  THR      3.8     2.7    -      -       -      +
    152F  PRO*     1.3    77.9    -      -       -      +
    154F  LEU*     1.3    61.5    +      -       -      +
    156F  PHE*     3.7     6.8    +      -       -      +
    157F  ARG*     3.3    21.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 154 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341E  ILE*     3.7    47.8    -      -       +      -
    351E  LEU*     3.9    18.3    -      -       +      +
    354E  LEU*     5.5     2.7    -      -       +      -
    359E  VAL*     4.4    10.1    -      -       +      -
    362E  VAL*     4.5    13.5    -      -       +      -
    121F  ILE*     4.4    22.9    -      -       +      -
    126F  MSE      5.8     2.7    -      -       +      -
    150F  THR*     3.0    21.2    +      -       +      +
    151F  GLU*     3.8     5.2    -      -       -      +
    153F  ALA*     1.3    76.3    -      -       -      +
    155F  ALA*     1.3    64.9    +      -       -      +
    157F  ARG*     3.2    11.9    -      -       +      +
    158F  ILE*     3.1    36.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 155 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80F  VAL*     4.2     6.7    -      -       +      -
    117F  VAL*     4.2    14.4    -      -       +      -
    118F  GLY*     3.3    38.1    -      -       -      +
    120F  ASN      5.8     0.2    -      -       -      +
    126F  MSE      4.6    12.1    -      -       -      -
    151F  GLU      3.1     7.6    +      -       -      +
    152F  PRO      3.9     2.2    -      -       -      +
    154F  LEU*     1.3    76.7    -      -       -      +
    156F  PHE*     1.3    58.9    +      -       -      +
    158F  ILE*     3.2     4.1    +      -       -      -
    159F  PHE*     2.8    37.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 156 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80F  VAL*     4.1     8.0    -      -       +      +
    140F  ILE*     4.2    20.6    -      -       +      -
    142F  VAL*     3.7    45.8    -      -       +      -
    152F  PRO      2.8    18.4    +      -       -      +
    153F  ALA*     3.9     7.2    -      -       -      +
    155F  ALA*     1.3    78.1    -      -       -      +
    157F  ARG*     1.3    58.0    +      -       -      +
    159F  PHE*     4.6     0.7    -      -       -      +
    160F  ARG*     2.8    69.4    +      -       +      +
    176F  ILE*     4.2    15.7    -      -       +      -
    187F  LEU*     4.3     8.7    -      -       +      -
    190F  LEU*     3.5    30.1    -      -       +      -
    196F  TYR*     4.3     3.4    -      +       -      -
----------------------------------------------------------
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Residues in contact with ARG 157 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341E  ILE*     4.6     4.9    -      -       -      +
    342E  GLU      2.7    34.6    +      -       -      +
    343E  SER*     3.7     0.6    -      -       -      +
    344E  GLU*     3.3    35.3    +      -       +      +
    347E  ASP*     3.4     7.5    +      -       -      -
    349E  ASP*     2.9    38.8    +      -       -      +
    351E  LEU*     3.8    21.9    +      -       -      +
    352E  ASN*     2.7    36.3    +      -       -      +
    355E  ALA*     5.5     0.2    -      -       -      +
    153F  ALA      3.3     9.7    +      -       -      +
    154F  LEU*     3.2    18.8    -      -       +      +
    156F  PHE*     1.3    83.5    -      -       -      +
    158F  ILE*     1.3    64.1    +      -       +      +
    160F  ARG*     4.2     7.1    +      -       -      +
    161F  LYS*     3.4    20.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 158 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    339E  LEU*     4.4     9.6    -      -       +      -
    340E  THR      5.9     4.0    -      -       -      +
    341E  ILE*     5.7     4.9    -      -       +      -
    359E  VAL*     3.9    27.6    -      -       +      -
    126F  MSE      4.0    18.2    -      -       -      -
    130F  MSE      3.6    30.5    -      -       +      -
    154F  LEU*     3.1    22.9    +      -       +      +
    155F  ALA      3.2     5.6    +      -       -      +
    157F  ARG*     1.3    83.5    -      -       +      +
    159F  PHE*     1.3    70.2    +      -       +      +
    161F  LYS*     3.6     5.9    +      -       -      +
    162F  LEU*     3.4    20.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 159 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78F  LEU*     3.7    27.1    -      -       +      -
     80F  VAL*     5.4     1.8    -      -       +      -
    117F  VAL*     3.6    26.9    -      -       +      -
    126F  MSE      3.7    33.9    -      -       +      -
    129F  LEU*     4.0    17.9    -      -       +      -
    130F  MSE      3.9    20.2    -      -       +      -
    133F  LEU*     3.8    20.6    -      -       +      -
    138F  PHE*     4.6     2.6    -      +       +      -
    140F  ILE*     3.7    10.8    -      -       +      +
    155F  ALA      2.8    31.8    +      -       -      +
    156F  PHE*     4.7     1.6    -      -       -      +
    158F  ILE*     1.3    79.6    -      -       +      +
    160F  ARG*     1.3    66.0    +      -       -      +
    161F  LYS      3.1     2.0    -      -       -      -
    162F  LEU*     3.2    17.0    +      -       +      +
    163F  LEU*     3.0    23.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 160 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    344E  GLU*     3.0    31.5    +      -       -      +
    140F  ILE*     4.0    10.4    -      -       -      +
    156F  PHE*     2.8    57.6    +      -       +      +
    157F  ARG*     4.2     6.6    +      -       -      +
    159F  PHE*     1.3    73.1    -      -       -      +
    161F  LYS*     1.3    57.6    +      -       -      +
    163F  LEU*     3.3     3.9    +      -       -      +
    164F  GLU*     3.0    57.8    +      -       -      +
    169F  LYS*     4.2     9.1    -      -       -      +
    176F  ILE*     3.9    11.7    -      -       +      -
    190F  LEU*     4.4    19.9    -      -       -      +
    194F  GLU*     5.1     1.8    +      -       -      -
    196F  TYR*     3.3    25.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 161 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    342E  GLU*     3.6    39.4    +      -       +      +
    157F  ARG      3.4    17.1    +      -       -      +
    158F  ILE*     3.7     7.0    -      -       -      +
    159F  PHE      3.1     0.4    -      -       -      -
    160F  ARG*     1.3    81.4    -      -       -      +
    162F  LEU*     1.3    57.0    +      -       +      +
    164F  GLU*     3.4    14.1    +      -       -      +
    165F  GLU*     2.9    68.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 162 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130F  MSE      3.7    43.1    -      -       +      -
    133F  LEU*     4.7     5.8    -      -       +      -
    138F  PHE*     4.4    10.4    -      -       +      -
    158F  ILE*     3.4    11.1    +      -       +      +
    159F  PHE*     3.2    28.3    +      -       +      +
    161F  LYS*     1.3    77.0    -      -       +      +
    163F  LEU*     1.3    64.4    +      -       -      +
    165F  GLU*     3.4    19.8    +      -       -      +
    166F  LYS*     3.0    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 163 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138F  PHE*     3.6    41.6    -      -       +      +
    140F  ILE*     4.1    10.5    -      -       +      -
    159F  PHE      3.0    13.2    +      -       -      +
    160F  ARG      3.3     8.3    +      -       -      +
    162F  LEU*     1.3    77.2    -      -       -      +
    164F  GLU*     1.3    56.4    +      -       -      +
    166F  LYS*     3.3     1.7    +      -       -      +
    167F  TYR*     3.0    59.5    +      -       +      +
    172F  ALA*     3.8    19.2    -      -       +      +
    175F  ARG*     4.1    11.4    -      -       +      +
    176F  ILE*     3.4    35.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 164 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    160F  ARG*     3.0    56.3    +      -       +      +
    161F  LYS*     3.8    13.8    -      -       -      +
    163F  LEU*     1.3    73.2    -      -       +      +
    165F  GLU*     1.3    62.6    +      -       +      +
    168F  GLY*     2.8    31.3    +      -       -      -
    169F  LYS*     3.1    40.3    +      -       +      +
    172F  ALA*     3.9    23.1    -      -       +      -
    176F  ILE*     5.5     0.4    -      -       +      +
    194F  GLU*     5.0     0.2    -      -       -      +
    196F  TYR*     4.7     2.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 165 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    161F  LYS*     2.9    55.5    +      -       +      +
    162F  LEU*     3.7    26.0    -      -       -      +
    164F  GLU*     1.3    79.1    -      -       +      +
    166F  LYS*     1.3    63.0    +      -       -      +
    168F  GLY      4.6     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 166 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133F  LEU      5.3     0.9    +      -       -      +
    135F  GLY*     4.8     8.1    -      -       -      +
    136F  LYS      3.1    37.2    +      -       -      +
    137F  ASP*     4.3     4.0    -      -       -      -
    138F  PHE*     3.9    15.7    -      -       +      -
    162F  LEU      3.0    16.7    +      -       -      +
    163F  LEU      3.6     4.5    -      -       -      +
    164F  GLU      3.2     0.2    -      -       -      -
    165F  GLU*     1.3    80.4    -      -       -      +
    167F  TYR*     1.3    93.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 167 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137F  ASP*     2.6    50.2    +      -       -      +
    138F  PHE      3.0     7.7    +      -       -      -
    163F  LEU*     3.0    49.6    +      -       +      +
    166F  LYS*     1.3    99.7    -      -       +      +
    168F  GLY*     1.3    64.3    +      -       -      +
    171F  GLU*     3.6    38.4    +      -       +      +
    172F  ALA*     4.2     2.2    -      -       -      +
    175F  ARG*     3.5    27.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 168 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    164F  GLU*     2.8    24.6    +      -       -      -
    165F  GLU      4.5     1.2    +      -       -      -
    166F  LYS      3.7     0.6    -      -       -      -
    167F  TYR*     1.3    77.3    -      -       -      +
    169F  LYS*     1.3    65.9    +      -       -      -
    170F  GLU      3.4     2.6    +      -       -      -
    172F  ALA*     3.0    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 169 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    160F  ARG*     4.2     5.9    -      -       -      +
    164F  GLU*     3.1    42.1    +      -       +      +
    168F  GLY*     1.3    71.4    -      -       -      -
    170F  GLU*     1.3    63.4    +      -       -      +
    172F  ALA*     3.8     6.7    -      -       -      +
    173F  ARG*     3.2    28.8    +      -       +      +
    194F  GLU*     3.6    29.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 170 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168F  GLY      3.4     1.0    -      -       -      -
    169F  LYS*     1.3    79.5    -      -       -      +
    171F  GLU*     1.3    61.7    +      -       -      +
    172F  ALA      3.5     0.2    +      -       -      -
    173F  ARG*     3.3    49.9    +      -       -      +
    174F  LYS*     3.6     7.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 171 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69F  LYS*     5.1     3.8    +      -       -      -
     73F  ASP*     5.2     0.3    -      -       -      +
    167F  TYR*     3.6    43.0    +      -       +      +
    168F  GLY      3.6     2.2    +      -       -      -
    170F  GLU*     1.3    77.3    -      -       -      +
    172F  ALA*     1.3    65.2    +      -       -      +
    174F  LYS*     3.1    35.0    +      -       -      +
    175F  ARG*     2.7    38.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 172 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163F  LEU*     4.1    22.2    -      -       +      +
    164F  GLU*     3.9    29.8    -      -       +      -
    167F  TYR*     4.2     3.1    -      -       -      +
    168F  GLY      3.0    19.5    +      -       -      +
    169F  LYS      3.8     4.3    -      -       -      +
    170F  GLU      3.3     0.6    -      -       -      -
    171F  GLU*     1.3    78.1    -      -       -      +
    173F  ARG*     1.3    58.4    +      -       -      +
    175F  ARG*     2.8    20.4    +      -       -      +
    176F  ILE*     3.2    22.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 173 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169F  LYS*     3.2    13.6    +      -       +      +
    170F  GLU*     3.3    41.1    +      -       -      +
    172F  ALA*     1.3    78.6    -      -       -      +
    174F  LYS*     1.3    79.6    +      -       -      +
    175F  ARG      3.3     0.9    +      -       -      -
    176F  ILE      3.5    16.8    +      -       -      +
    194F  GLU*     3.2    38.2    +      -       -      +
    195F  GLY*     4.2    14.9    +      -       -      +
    196F  TYR*     3.7    26.4    -      -       +      -
    197F  GLU      4.8     1.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 174 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69F  LYS*     3.1    36.2    +      -       -      +
    170F  GLU*     3.6    17.7    -      -       +      +
    171F  GLU*     3.1    28.8    +      -       -      +
    172F  ALA      3.1     0.8    -      -       -      -
    173F  ARG*     1.3    95.8    -      -       -      +
    175F  ARG*     1.3    58.3    +      -       -      +
    176F  ILE      3.5     0.7    -      -       -      -
    177F  TYR*     3.4    11.2    +      -       -      -
----------------------------------------------------------
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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).

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