Contacts of the helix formed by residues 239 - 260 (chain C) in PDB entry 2I2X


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 ALA 239 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179C  ASN*     5.5     0.4    +      -       -      -
    238C  LEU*     1.3    76.6    -      -       -      +
    240C  HIS*     1.3    60.7    +      -       -      +
    241C  THR*     3.8     7.9    -      -       -      +
    242C  ILE*     2.8    30.2    +      -       +      +
    243C  ALA      3.0     9.7    +      -       -      -
    417C  PHE*     4.5    16.2    -      -       +      -
    418C  GLU*     5.1     5.2    -      -       +      -
    421C  ALA*     3.7    29.4    -      -       +      -
     94D  PHE*     3.7    14.6    -      -       -      -
     96D  PRO*     5.6     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 240 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230C  GLY*     2.7    27.7    +      -       -      -
    231C  GLY      3.2    12.9    +      -       -      -
    232C  GLY      3.1    26.2    +      -       -      -
    233C  LEU*     3.9     9.8    -      -       +      +
    235C  ASN*     5.2     2.3    +      -       -      +
    238C  LEU      3.4    14.4    -      -       -      -
    239C  ALA*     1.3    74.0    -      -       -      +
    241C  THR*     1.3    56.9    +      -       -      +
    243C  ALA*     3.2     7.5    +      -       -      +
    244C  VAL*     3.0    30.7    +      -       -      +
    298C  VAL*     5.8     2.0    -      -       +      -
    364C  ASP*     2.6    40.7    +      -       -      +
    365C  PRO*     4.0     5.4    -      -       +      -
    366C  GLN*     3.5    13.9    +      -       -      +
    418C  GLU*     4.0    18.7    +      -       -      +
     15D  ARG*     4.5     1.2    +      -       -      -
     94D  PHE*     5.4     2.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with THR 241 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239C  ALA*     3.8     9.2    -      -       -      +
    240C  HIS*     1.3    74.8    -      -       -      +
    242C  ILE*     1.3    59.3    +      -       -      +
    244C  VAL*     3.4    16.5    -      -       -      +
    245C  ILE*     3.3    21.1    -      -       -      +
    365C  PRO*     4.0    17.5    -      -       +      -
    404C  ILE*     4.4     6.3    -      -       +      -
    414C  LEU*     4.1    13.2    -      -       +      -
    418C  GLU*     2.8    48.1    +      -       +      +
    421C  ALA*     3.8     5.0    -      -       -      +
    422C  LEU*     3.9    21.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 242 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176C  VAL*     6.1     1.1    -      -       +      -
    179C  ASN*     3.4    34.1    -      -       +      +
    181C  ILE*     3.7    31.6    -      -       +      -
    184C  LEU*     4.0    12.7    -      -       +      +
    238C  LEU*     4.2    15.9    -      -       +      -
    239C  ALA*     2.8    21.4    +      -       +      +
    241C  THR*     1.3    79.3    -      -       -      +
    243C  ALA*     1.3    66.2    +      -       -      +
    244C  VAL      3.1     1.3    -      -       -      -
    245C  ILE*     3.1    14.1    +      -       +      +
    246C  ALA*     3.1    12.5    +      -       -      +
    421C  ALA*     4.0    31.2    -      -       +      +
    425C  ALA*     5.1     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 243 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223C  ALA      5.3     1.7    -      -       -      +
    226C  ALA*     4.2    19.8    -      -       -      +
    227C  MET*     4.4     0.9    -      -       -      +
    230C  GLY*     5.5     2.2    -      -       -      -
    238C  LEU*     4.1    19.6    -      -       +      +
    239C  ALA      3.0    10.7    +      -       -      +
    240C  HIS*     3.6     9.0    -      -       -      +
    242C  ILE*     1.3    76.9    -      -       -      +
    244C  VAL*     1.3    62.4    +      -       -      +
    246C  ALA*     3.1    13.9    +      -       -      +
    247C  ARG*     3.1    11.8    +      -       -      +
    366C  GLN*     3.6    28.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 244 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240C  HIS      3.0    17.3    +      -       -      +
    241C  THR*     3.4    24.7    -      -       -      +
    243C  ALA*     1.3    77.3    -      -       -      +
    245C  ILE*     1.3    56.7    +      -       -      +
    247C  ARG*     3.2     8.1    +      -       +      +
    248C  ALA      3.0    22.2    +      -       -      -
    365C  PRO*     3.5    21.3    -      -       +      +
    366C  GLN*     3.9    19.9    -      -       -      +
    369C  MET*     3.4    41.2    -      -       +      +
    400C  CYS*     3.8    14.7    -      -       -      -
    404C  ILE*     4.3     7.0    -      -       +      -
    422C  LEU*     5.7     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 245 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181C  ILE*     4.6     9.0    -      -       +      -
    184C  LEU*     5.5     2.7    -      -       +      -
    241C  THR      3.3    20.6    -      -       -      +
    242C  ILE*     3.1    13.1    +      -       +      +
    244C  VAL*     1.3    75.2    -      -       +      +
    246C  ALA*     1.3    65.4    +      -       -      +
    248C  ALA*     3.2     2.9    +      -       -      +
    249C  ILE*     3.1    39.6    +      -       +      +
    397C  ALA*     4.2    16.6    -      -       +      +
    400C  CYS*     4.1    19.3    -      -       -      -
    401C  CYS*     3.8    20.6    -      -       -      -
    422C  LEU*     4.5     7.0    -      -       +      -
    425C  ALA*     3.7    28.7    -      -       +      -
    429C  LEU*     4.4     8.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 246 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172C  PHE*     4.9     1.1    -      -       +      -
    184C  LEU*     4.8    12.5    -      -       +      +
    188C  ILE*     4.0    23.8    -      -       +      +
    223C  ALA*     4.5     9.6    -      -       -      -
    226C  ALA*     4.0    22.2    -      -       +      -
    242C  ILE      3.1    10.3    +      -       -      +
    243C  ALA      3.1    10.2    +      -       -      +
    245C  ILE*     1.3    77.1    -      -       -      +
    247C  ARG*     1.3    56.0    +      -       -      +
    249C  ILE*     3.2     8.0    +      -       -      +
    250C  SER*     2.9    28.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 247 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219C  ASP      5.4     0.8    +      -       -      -
    223C  ALA*     3.5    24.6    +      -       -      +
    224C  ASN*     2.9    29.1    +      -       -      -
    227C  MET*     3.6    35.2    -      -       -      +
    243C  ALA      3.1    11.0    +      -       -      +
    244C  VAL*     3.3    13.2    -      -       +      +
    246C  ALA*     1.3    75.9    -      -       -      +
    248C  ALA*     1.3    63.8    +      -       -      +
    250C  SER*     2.7    25.1    +      -       -      -
    251C  ALA*     3.4     3.5    +      -       -      +
    269C  CYS      4.3     0.4    +      -       -      -
    271C  TYR*     3.5    22.4    -      -       -      +
    272C  GLU*     3.1    43.7    +      -       +      +
    275C  ILE*     4.9     0.4    -      -       +      +
    299C  MET*     5.0     2.2    -      -       -      +
    366C  GLN*     5.2     2.9    +      -       +      +
    369C  MET*     3.7    16.2    -      -       +      -
    370C  LEU*     3.8    19.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 248 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244C  VAL      3.0     9.2    +      -       -      +
    245C  ILE      3.2     7.8    +      -       -      +
    247C  ARG*     1.3    76.8    -      -       -      +
    249C  ILE*     1.3    60.7    +      -       -      +
    251C  ALA*     3.3    12.6    +      -       -      +
    252C  PRO*     3.3    10.0    -      -       -      +
    275C  ILE*     4.8     4.5    -      -       -      -
    369C  MET*     3.5    13.5    -      -       +      +
    378C  VAL*     4.6     4.2    -      -       +      +
    396C  ALA*     3.6    22.9    -      -       +      +
    397C  ALA*     4.3     1.6    -      -       -      -
    400C  CYS*     3.5    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 249 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181C  ILE*     5.1     1.8    -      -       +      +
    184C  LEU*     4.4    10.1    -      -       +      -
    185C  LEU*     4.1    31.4    -      -       +      +
    188C  ILE*     3.7    11.2    -      -       +      +
    189C  GLY*     3.4    32.4    -      -       -      +
    245C  ILE*     3.1    32.3    +      -       +      +
    246C  ALA*     3.7     7.0    -      -       -      +
    248C  ALA*     1.3    70.9    -      -       -      +
    250C  SER*     1.3    58.2    +      -       -      +
    251C  ALA      3.1     4.9    -      -       -      -
    252C  PRO*     3.0    24.0    -      -       -      +
    253C  ARG*     3.7     4.9    +      -       -      +
    393C  ALA*     4.2    14.8    -      -       +      +
    397C  ALA*     3.8    22.4    -      -       +      -
    429C  LEU*     5.3     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 250 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188C  ILE*     3.6    11.4    -      -       -      +
    219C  ASP*     3.3    32.8    -      -       -      -
    223C  ALA*     3.7     4.7    -      -       -      -
    246C  ALA      2.9    10.9    +      -       -      -
    247C  ARG*     2.7    21.5    +      -       -      -
    249C  ILE*     1.3    76.8    -      -       -      +
    251C  ALA*     1.3    56.7    +      -       -      +
    253C  ARG*     3.4     1.8    +      -       -      +
    254C  SER*     2.9    32.7    +      -       -      -
    272C  GLU*     3.0    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 251 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    247C  ARG      3.4     0.6    +      -       -      +
    248C  ALA      3.3     8.2    +      -       -      +
    249C  ILE      3.1     1.8    -      -       -      -
    250C  SER*     1.3    81.8    +      -       -      +
    252C  PRO*     1.4    63.6    -      -       +      +
    254C  SER      3.3     0.5    +      -       -      -
    255C  LEU*     2.8    30.1    +      -       -      +
    272C  GLU*     4.0    14.1    -      -       +      +
    275C  ILE*     3.6    45.1    -      -       +      -
    276C  VAL*     3.8     7.1    -      -       +      +
    279C  ILE*     5.9     0.8    -      -       -      +
    382C  ILE*     4.2     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 252 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    189C  GLY*     5.5     0.2    -      -       -      -
    193C  SER*     4.0     3.5    +      -       -      +
    248C  ALA      3.3    11.4    -      -       -      +
    249C  ILE      3.0    24.5    -      -       -      +
    251C  ALA*     1.4    80.7    -      -       +      +
    253C  ARG*     1.3    64.6    +      -       -      +
    255C  LEU*     3.5    13.6    -      -       +      +
    256C  VAL*     3.5     3.8    -      -       -      +
    382C  ILE*     3.8    19.4    -      -       +      -
    389C  ILE      5.3     0.7    -      -       -      +
    392C  ARG*     3.1    49.9    +      -       +      +
    393C  ALA*     3.7    28.7    -      -       +      -
    396C  ALA*     4.5     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 253 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165C  SER*     3.1    29.7    +      -       -      -
    167C  GLY      5.5     3.2    +      -       -      +
    188C  ILE*     3.5    35.4    -      -       +      +
    189C  GLY*     4.8     0.4    -      -       -      -
    192C  GLY*     3.9    20.1    -      -       -      -
    193C  SER*     3.6    11.2    +      -       -      +
    196C  MET*     3.5    25.7    -      -       +      +
    217C  ASP*     3.1    21.8    +      -       -      -
    218C  THR      3.0    27.9    +      -       -      +
    219C  ASP*     3.1    25.9    +      -       -      +
    221C  ALA*     6.1     0.2    -      -       -      +
    222C  GLN*     4.2     2.4    +      -       -      -
    249C  ILE      4.1     0.9    -      -       -      +
    250C  SER      3.4     5.6    +      -       -      +
    251C  ALA      3.2     0.8    -      -       -      -
    252C  PRO*     1.3    82.5    -      -       -      +
    254C  SER*     1.3    83.2    +      -       -      +
    256C  VAL*     3.0    22.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 254 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196C  MET*     3.9     2.6    -      -       -      +
    217C  ASP*     5.2     3.7    +      -       -      +
    218C  THR*     3.9     4.5    -      -       -      -
    219C  ASP      3.4     1.2    +      -       -      -
    250C  SER      2.9    18.3    +      -       -      -
    251C  ALA      4.1     1.3    -      -       -      -
    253C  ARG*     1.3    98.9    +      -       -      +
    255C  LEU*     1.3    62.8    +      -       -      +
    256C  VAL      3.1     1.0    +      -       -      -
    257C  ALA*     3.3    14.2    +      -       -      +
    258C  TYR*     3.5    17.7    -      -       -      -
    272C  GLU*     2.6    35.4    +      -       -      -
    273C  ASN*     5.1     4.0    -      -       -      -
    276C  VAL*     4.3     6.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 255 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6C  TYR*     3.8    17.9    -      -       +      +
    251C  ALA      2.8    19.4    +      -       -      +
    252C  PRO*     3.5     8.3    -      -       +      +
    254C  SER*     1.3    77.8    -      -       -      +
    256C  VAL*     1.3    62.2    +      -       -      +
    258C  TYR*     3.1    16.7    +      -       -      -
    259C  GLU*     3.2    31.1    +      -       -      +
    276C  VAL*     4.1    11.4    -      -       +      +
    279C  ILE*     4.0    30.5    -      -       +      -
    280C  THR*     3.6    29.4    -      -       +      -
    382C  ILE*     4.2    10.3    -      -       +      -
    383C  VAL*     5.6     0.2    -      -       +      -
    392C  ARG*     3.9    13.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 256 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5C  ARG*     4.0    13.9    -      -       -      +
    193C  SER*     3.7    25.6    -      -       -      +
    196C  MET*     3.8     6.1    -      -       +      -
    197C  GLU*     3.5    42.6    -      -       +      +
    252C  PRO      3.5     3.1    -      -       -      +
    253C  ARG      3.0    18.8    +      -       -      +
    255C  LEU*     1.3    73.2    -      -       -      +
    257C  ALA*     1.3    65.7    +      -       -      +
    259C  GLU*     3.1    10.6    +      -       +      +
    260C  ALA*     2.9    21.3    +      -       +      +
    389C  ILE*     5.0     0.2    -      -       +      -
    392C  ARG*     3.4    22.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 257 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196C  MET*     3.6    17.7    -      -       +      +
    200C  TRP*     3.7    34.7    -      -       +      +
    217C  ASP      4.4     7.6    -      -       -      +
    254C  SER      3.3    13.2    +      -       -      +
    255C  LEU      3.2     0.6    -      -       -      -
    256C  VAL*     1.3    76.5    -      -       -      +
    258C  TYR*     1.3    67.0    +      -       +      +
    260C  ALA*     3.2    13.3    +      -       -      +
    261C  GLY      3.2     1.4    +      -       -      -
    262C  ALA*     3.0    28.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 258 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6C  TYR*     4.4     7.8    +      -       +      +
    215C  ALA      3.2    20.0    -      -       -      -
    216C  GLY*     3.6    11.5    -      -       -      -
    217C  ASP      4.2     5.3    +      -       -      -
    254C  SER*     3.5    25.1    -      -       -      -
    255C  LEU      3.1     7.9    +      -       -      +
    257C  ALA*     1.3    74.1    -      -       +      +
    259C  GLU*     1.3    67.3    +      -       -      +
    260C  ALA      3.0     1.6    +      -       -      -
    261C  GLY*     3.3     8.8    +      -       -      -
    262C  ALA*     3.4    22.5    -      -       +      +
    264C  GLY*     3.7    10.3    -      -       -      -
    266C  GLY*     3.1    28.2    -      -       -      -
    273C  ASN*     4.8     2.5    +      -       -      -
    276C  VAL*     3.6    25.6    -      -       +      -
    280C  THR*     3.9    11.9    -      -       +      -
    282C  MET*     3.5    35.1    -      -       +      +
    284C  MET*     3.7    12.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 259 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3C  ALA*     4.0    13.7    -      -       -      +
      4C  LYS*     3.1    44.9    +      -       -      +
      5C  ARG*     3.3    19.7    +      -       -      +
      6C  TYR*     3.0    32.9    +      -       +      -
    255C  LEU*     3.2    18.0    +      -       -      +
    256C  VAL*     3.1    13.0    +      -       -      +
    258C  TYR*     1.3    76.8    -      -       -      +
    260C  ALA*     1.3    57.9    +      -       -      +
    261C  GLY      3.8     0.5    +      -       -      -
    392C  ARG*     2.5    46.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 260 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3C  ALA*     4.3    15.5    -      -       -      +
    197C  GLU*     4.5     9.4    -      -       +      +
    200C  TRP*     3.4    22.9    -      -       +      +
    201C  THR*     3.9    22.5    +      -       -      +
    204C  SER*     3.3    13.7    +      -       -      -
    256C  VAL      2.9    16.4    +      -       -      +
    257C  ALA      3.2     6.5    +      -       -      +
    258C  TYR      3.0     0.6    -      -       -      -
    259C  GLU*     1.3    77.2    -      -       -      +
    261C  GLY*     1.3    54.2    +      -       -      +
    262C  ALA      3.8     0.2    -      -       -      -
----------------------------------------------------------
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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