Contacts of the helix formed by residues 239 - 260 (chain K) 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 K).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179K  ASN*     5.5     0.6    +      -       -      -
    238K  LEU*     1.3    76.4    -      -       -      +
    240K  HIS*     1.3    60.7    +      -       -      +
    241K  THR*     3.8     8.1    -      -       -      +
    242K  ILE*     2.9    28.9    +      -       +      +
    243K  ALA*     3.1     9.7    +      -       -      +
    417K  PHE*     4.4    16.6    -      -       +      -
    418K  GLU*     5.0     4.3    -      -       -      -
    421K  ALA*     3.8    29.4    -      -       +      -
     94L  PHE*     3.6    14.5    -      -       +      -
     96L  PRO*     5.6     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 240 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230K  GLY*     2.7    28.1    +      -       -      -
    231K  GLY      3.2    18.8    -      -       -      -
    232K  GLY      3.2    19.1    +      -       -      -
    233K  LEU*     4.1     8.6    +      -       +      -
    235K  ASN*     5.1     3.5    +      -       -      +
    238K  LEU      3.3    15.5    -      -       -      -
    239K  ALA*     1.3    71.6    -      -       -      +
    241K  THR*     1.3    56.9    +      -       -      +
    243K  ALA*     3.8     5.8    -      -       -      -
    244K  VAL*     3.1    24.8    +      -       -      +
    298K  VAL*     5.8     2.0    -      -       +      -
    364K  ASP*     2.6    39.1    +      -       -      +
    365K  PRO*     3.9    10.8    -      -       +      +
    366K  GLN*     3.4    19.8    +      -       -      +
    418K  GLU*     4.0    17.0    -      -       -      +
     15L  ARG*     4.5     1.8    +      -       -      -
     94L  PHE*     5.7     1.8    -      +       -      -
----------------------------------------------------------
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Residues in contact with THR 241 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239K  ALA*     3.8     8.1    -      -       -      +
    240K  HIS*     1.3    77.6    -      -       -      +
    242K  ILE*     1.3    61.0    +      -       -      +
    244K  VAL*     3.4    16.2    -      -       +      +
    245K  ILE*     3.4    20.8    -      -       -      +
    365K  PRO*     4.1    14.8    -      -       +      +
    404K  ILE*     4.4     5.6    -      -       +      -
    414K  LEU*     4.1    15.3    -      -       +      -
    418K  GLU*     2.8    48.0    +      -       +      +
    421K  ALA*     3.9     0.3    -      -       -      +
    422K  LEU*     3.8    26.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 242 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176K  VAL*     6.0     1.8    -      -       +      -
    179K  ASN*     3.2    41.3    -      -       +      +
    181K  ILE*     4.0    27.1    -      -       +      -
    184K  LEU*     4.1    15.0    -      -       +      -
    238K  LEU*     4.4    16.4    -      -       +      -
    239K  ALA*     2.9    17.8    +      -       +      +
    241K  THR*     1.3    78.0    +      -       -      +
    243K  ALA*     1.3    66.0    +      -       -      +
    244K  VAL      3.2     1.6    -      -       -      -
    245K  ILE*     3.0    16.6    +      -       +      +
    246K  ALA*     3.0    12.5    +      -       +      +
    421K  ALA*     4.0    33.4    -      -       +      +
    425K  ALA*     4.9     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 243 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223K  ALA      5.4     1.2    -      -       -      +
    226K  ALA*     4.3    18.4    -      -       -      +
    227K  MET*     4.5     1.1    -      -       -      +
    230K  GLY*     5.4     2.2    -      -       -      -
    238K  LEU*     4.1    18.7    -      -       +      +
    239K  ALA      3.1    11.4    +      -       -      +
    240K  HIS*     3.7     6.3    -      -       +      +
    242K  ILE*     1.3    75.1    -      -       -      +
    244K  VAL*     1.3    62.7    +      -       -      +
    246K  ALA*     3.1     7.0    +      -       -      +
    247K  ARG*     3.0    20.1    +      -       -      +
    366K  GLN*     3.3    32.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 244 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240K  HIS      3.1    16.4    +      -       -      +
    241K  THR*     3.4    17.7    -      -       -      +
    242K  ILE      3.2     0.4    -      -       -      -
    243K  ALA*     1.3    71.4    -      -       -      +
    245K  ILE*     1.3    70.0    +      -       +      +
    247K  ARG*     3.1     6.1    +      -       +      -
    248K  ALA      2.9    19.1    +      -       -      -
    365K  PRO*     3.4    16.6    -      -       +      +
    366K  GLN*     3.8    16.7    -      -       -      +
    369K  MET*     3.4    44.8    -      -       +      +
    400K  CYS*     3.6    14.4    -      -       -      -
    404K  ILE*     4.0    17.5    -      -       +      -
    422K  LEU*     5.8     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 245 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181K  ILE*     4.2    17.5    -      -       +      -
    184K  LEU*     5.6     2.7    -      -       +      -
    241K  THR      3.4    19.7    -      -       -      +
    242K  ILE*     3.0    12.7    +      -       +      +
    244K  VAL*     1.3    78.3    -      -       +      +
    246K  ALA*     1.3    62.7    +      -       -      +
    248K  ALA*     3.2     3.0    +      -       -      +
    249K  ILE*     3.0    41.4    +      -       +      +
    397K  ALA*     4.3    12.6    -      -       +      +
    400K  CYS*     4.1    14.6    -      -       -      -
    401K  CYS*     3.8    25.4    -      -       -      -
    422K  LEU*     4.5     5.8    -      -       +      -
    425K  ALA*     3.6    31.2    -      -       +      -
    429K  LEU*     4.6     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 246 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172K  PHE*     5.1     1.3    -      -       +      -
    184K  LEU*     4.6    14.6    -      -       +      +
    188K  ILE*     4.1    22.1    -      -       +      +
    223K  ALA*     4.2     7.3    -      -       -      +
    226K  ALA*     4.1    22.0    -      -       +      -
    242K  ILE*     3.0    12.4    +      -       +      +
    243K  ALA      3.4     9.2    -      -       -      +
    245K  ILE*     1.3    76.7    -      -       -      +
    247K  ARG*     1.3    61.7    +      -       -      +
    249K  ILE*     3.4     7.3    +      -       -      +
    250K  SER*     3.1    22.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 247 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219K  ASP      5.4     0.8    +      -       -      -
    223K  ALA*     3.3    30.1    +      -       +      +
    224K  ASN*     2.6    31.7    +      -       -      -
    227K  MET*     3.8    20.4    -      -       -      +
    243K  ALA      3.0    11.2    +      -       -      +
    244K  VAL*     3.1    13.0    +      -       +      +
    246K  ALA*     1.3    74.1    -      -       -      +
    248K  ALA*     1.3    66.1    +      -       -      +
    250K  SER*     2.6    23.0    +      -       -      -
    251K  ALA*     3.4     3.8    +      -       -      -
    269K  CYS      4.4     0.4    +      -       -      -
    271K  TYR*     3.4    27.7    -      -       -      +
    272K  GLU*     2.9    47.0    +      -       +      +
    275K  ILE*     5.3     0.4    -      -       +      -
    299K  MET*     5.4     2.0    -      -       -      +
    366K  GLN*     5.5     2.3    +      -       +      -
    369K  MET*     3.8    14.6    -      -       +      -
    370K  LEU*     4.0    20.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 248 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244K  VAL      2.9     7.4    +      -       -      +
    245K  ILE      3.2     6.0    +      -       -      +
    247K  ARG*     1.3    75.0    -      -       -      +
    249K  ILE*     1.3    61.3    +      -       -      +
    251K  ALA*     3.3     6.4    +      -       -      +
    252K  PRO*     3.2    17.8    -      -       -      +
    275K  ILE*     4.7     5.6    -      -       -      -
    369K  MET*     3.4    18.1    -      -       +      +
    378K  VAL*     4.5     4.4    -      -       +      +
    396K  ALA*     3.5    23.1    -      -       +      +
    397K  ALA*     4.6     0.4    -      -       -      +
    400K  CYS*     3.6    31.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 249 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181K  ILE*     5.0     3.8    -      -       +      +
    184K  LEU*     4.1    12.8    -      -       +      +
    185K  LEU*     4.0    28.7    -      -       +      +
    188K  ILE*     3.8    12.8    -      -       +      +
    189K  GLY*     3.6    30.6    -      -       -      +
    245K  ILE*     3.0    33.2    +      -       +      +
    246K  ALA*     3.8     5.4    -      -       -      +
    248K  ALA*     1.3    76.8    -      -       -      +
    250K  SER*     1.3    61.8    +      -       -      +
    252K  PRO*     3.3    17.2    -      -       -      +
    253K  ARG*     3.8     4.2    +      -       -      +
    393K  ALA*     4.1    14.8    -      -       +      +
    397K  ALA*     3.8    24.5    -      -       +      -
    429K  LEU*     5.4     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 250 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188K  ILE*     3.6    10.1    -      -       -      -
    219K  ASP*     3.2    33.2    -      -       -      -
    223K  ALA*     3.8     4.4    -      -       -      +
    246K  ALA      3.1    11.5    +      -       -      -
    247K  ARG*     2.6    22.9    +      -       -      -
    249K  ILE*     1.3    76.4    -      -       -      +
    251K  ALA*     1.3    60.5    +      -       -      +
    253K  ARG*     3.4     2.0    +      -       -      +
    254K  SER*     2.9    32.4    +      -       -      -
    272K  GLU*     3.4    20.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 251 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    247K  ARG      3.4     0.8    +      -       -      +
    248K  ALA      3.3     7.9    +      -       -      +
    249K  ILE      3.1     1.2    -      -       -      -
    250K  SER*     1.3    80.2    +      -       -      +
    252K  PRO*     1.3    65.9    -      -       +      +
    254K  SER*     3.0     4.7    +      -       -      -
    255K  LEU*     2.8    28.6    +      -       -      +
    272K  GLU*     4.0    14.6    -      -       +      +
    275K  ILE*     3.8    45.1    -      -       +      -
    276K  VAL*     4.1     6.4    -      -       +      +
    279K  ILE*     6.3     0.2    -      -       -      -
    382K  ILE*     3.9     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 252 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    189K  GLY*     6.1     0.2    -      -       -      -
    193K  SER*     4.2     3.4    +      -       -      +
    248K  ALA      3.2    15.0    -      -       -      +
    249K  ILE      3.3    11.9    -      -       -      +
    251K  ALA*     1.3    92.5    -      -       +      +
    253K  ARG*     1.3    59.7    +      -       -      +
    255K  LEU*     3.5    14.4    -      -       +      +
    256K  VAL*     3.5     1.9    -      -       -      +
    382K  ILE*     3.7    20.6    -      -       +      -
    389K  ILE      5.4     0.7    -      -       -      +
    392K  ARG*     2.9    52.8    +      -       +      +
    393K  ALA*     3.9    26.7    -      -       +      +
    396K  ALA*     4.4     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 253 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165K  SER*     3.2    36.8    +      -       -      -
    167K  GLY      5.4     4.2    +      -       -      +
    188K  ILE*     3.3    38.8    -      -       +      +
    189K  GLY*     4.9     0.6    -      -       -      -
    192K  GLY*     3.9    18.3    +      -       -      -
    193K  SER*     3.7    10.9    +      -       -      +
    196K  MET*     3.5    23.1    -      -       +      +
    217K  ASP*     3.3     7.1    +      -       -      +
    218K  THR      3.0    34.7    +      -       -      +
    219K  ASP*     3.2    22.7    +      -       -      +
    222K  GLN*     4.3     2.2    +      -       -      -
    249K  ILE      4.1     1.3    -      -       -      +
    250K  SER      3.4     5.8    +      -       -      +
    251K  ALA      3.1     0.6    -      -       -      -
    252K  PRO*     1.3    80.4    -      -       -      +
    254K  SER*     1.3    86.4    +      -       -      +
    256K  VAL*     3.2    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 254 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196K  MET*     3.9     5.6    -      -       -      +
    217K  ASP*     5.4     3.9    -      -       -      +
    218K  THR*     4.0     4.4    -      -       -      -
    219K  ASP*     3.5     2.1    +      -       -      +
    250K  SER      2.9    15.9    +      -       -      -
    251K  ALA      3.9     2.2    -      -       -      -
    253K  ARG*     1.3    95.7    +      -       -      +
    255K  LEU*     1.3    63.4    +      -       -      +
    256K  VAL      3.1     3.7    +      -       -      -
    257K  ALA*     3.3    10.4    +      -       -      +
    258K  TYR*     3.3    20.7    -      -       -      -
    272K  GLU*     2.9    30.8    +      -       -      -
    273K  ASN*     5.3     3.6    -      -       -      -
    276K  VAL*     4.4     7.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 255 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6K  TYR*     3.7    17.9    -      -       +      +
    251K  ALA      2.8    16.2    +      -       -      +
    252K  PRO*     3.5     7.6    -      -       +      +
    254K  SER*     1.3    77.9    -      -       -      +
    256K  VAL*     1.3    62.2    +      -       -      +
    258K  TYR*     3.1    19.1    +      -       -      +
    259K  GLU*     3.2    33.3    +      -       -      +
    276K  VAL*     4.2    10.7    -      -       +      +
    279K  ILE*     3.8    19.5    -      -       +      -
    280K  THR*     3.5    32.1    -      -       +      -
    382K  ILE*     4.1    21.3    -      -       +      -
    392K  ARG*     3.8    15.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 256 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3K  ALA      5.7     0.4    -      -       -      +
      5K  ARG*     4.1    12.3    -      -       -      +
    193K  SER*     3.7    26.9    -      -       -      +
    196K  MET*     3.7     8.7    -      -       +      +
    197K  GLU*     3.5    38.8    -      -       +      +
    252K  PRO      3.5     3.6    -      -       -      +
    253K  ARG      3.3    16.4    -      -       -      +
    254K  SER      3.1     0.8    -      -       -      -
    255K  LEU*     1.3    74.2    -      -       -      +
    257K  ALA*     1.3    66.4    +      -       -      +
    258K  TYR      3.0     0.2    +      -       -      -
    259K  GLU*     3.0     9.2    +      -       +      +
    260K  ALA*     2.8    24.6    +      -       +      +
    392K  ARG*     3.5    20.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 257 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196K  MET*     3.4    20.9    -      -       +      +
    200K  TRP*     3.7    35.7    -      -       +      +
    217K  ASP      4.3     8.1    -      -       -      +
    254K  SER      3.3     9.2    +      -       -      +
    255K  LEU      3.3     0.4    -      -       -      -
    256K  VAL*     1.3    77.6    -      -       -      +
    258K  TYR*     1.3    59.1    +      -       +      +
    260K  ALA*     3.5     3.3    +      -       -      +
    261K  GLY      3.2     8.5    +      -       -      -
    262K  ALA*     2.8    36.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 258 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6K  TYR*     4.3     8.1    +      -       +      -
    215K  ALA      3.4    19.1    -      -       -      -
    216K  GLY*     3.7    11.3    -      -       -      -
    217K  ASP      4.1     5.7    +      -       -      -
    254K  SER*     3.3    25.4    -      -       -      -
    255K  LEU      3.1     6.9    +      -       -      +
    256K  VAL      3.0     0.8    -      -       -      -
    257K  ALA*     1.3    76.6    -      -       +      +
    259K  GLU*     1.3    65.9    +      -       -      +
    260K  ALA      3.1     1.9    +      -       -      -
    261K  GLY*     3.3     9.0    +      -       -      -
    262K  ALA*     3.5    27.7    -      -       +      +
    264K  GLY*     3.8     7.4    -      -       -      -
    266K  GLY*     3.1    28.4    -      -       -      -
    273K  ASN*     4.7     2.5    +      -       -      -
    276K  VAL*     3.5    27.1    -      -       +      -
    280K  THR*     4.0    13.5    -      -       +      -
    282K  MET*     3.6    28.7    -      -       -      +
    284K  MET*     3.8    15.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 259 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3K  ALA*     4.3     6.4    -      -       -      +
      4K  LYS*     3.0    50.2    +      -       -      +
      5K  ARG*     3.2    22.6    +      -       -      +
      6K  TYR*     2.8    37.1    +      -       +      -
    255K  LEU*     3.2    17.0    +      -       -      +
    256K  VAL*     3.0     9.2    +      -       -      +
    258K  TYR*     1.3    76.2    -      -       -      +
    260K  ALA*     1.3    59.0    +      -       -      +
    261K  GLY      3.4     0.7    +      -       -      -
    392K  ARG*     2.6    47.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 260 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3K  ALA*     4.3    15.7    -      -       -      +
    197K  GLU*     4.5     9.6    -      -       -      +
    200K  TRP*     3.5    26.4    -      -       +      +
    201K  THR*     3.8    23.9    +      -       -      +
    204K  SER*     3.4    12.4    +      -       -      -
    256K  VAL*     2.8    16.6    +      -       +      +
    257K  ALA      3.6     2.7    -      -       -      -
    259K  GLU*     1.3    77.1    -      -       -      +
    261K  GLY*     1.3    53.7    +      -       -      +
    262K  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