Contacts of the helix formed by residues 239 - 260 (chain A) 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 A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179A  ASN*     5.6     0.4    +      -       -      -
    238A  LEU*     1.3    78.1    -      -       -      +
    240A  HIS*     1.3    61.7    +      -       -      +
    241A  THR*     3.8    15.7    -      -       -      +
    242A  ILE*     2.9    30.4    +      -       +      +
    243A  ALA*     3.2     8.7    +      -       -      +
    417A  PHE*     4.4    17.7    -      -       +      -
    418A  GLU*     4.9     5.6    -      -       +      -
    421A  ALA*     4.0    19.1    -      -       +      -
     94B  PHE*     3.6    14.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 240 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  GLY*     2.8    26.6    +      -       -      -
    231A  GLY      3.3    18.7    +      -       -      -
    232A  GLY      3.3    18.1    +      -       -      -
    233A  LEU*     3.9    10.3    -      -       +      -
    235A  ASN*     5.2     1.6    +      -       -      +
    238A  LEU      3.4    15.5    -      -       -      -
    239A  ALA*     1.3    73.1    -      -       -      +
    241A  THR*     1.3    57.6    +      -       -      +
    243A  ALA*     3.2     7.5    +      -       -      +
    244A  VAL*     3.1    28.9    +      -       -      +
    298A  VAL*     5.6     1.8    -      -       +      -
    364A  ASP*     2.5    39.9    +      -       -      +
    365A  PRO*     4.0     7.1    -      -       +      +
    366A  GLN*     3.5    14.9    +      -       -      +
    418A  GLU*     3.7    21.2    +      -       -      +
     15B  ARG*     4.2     2.2    +      -       -      -
     94B  PHE*     5.8     2.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with THR 241 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239A  ALA*     3.8     8.1    -      -       -      +
    240A  HIS*     1.3    78.4    -      -       -      +
    242A  ILE*     1.3    57.8    +      -       -      +
    244A  VAL*     3.5    12.2    -      -       -      +
    245A  ILE*     3.3    25.6    -      -       -      +
    365A  PRO*     4.0    17.7    -      -       +      -
    404A  ILE*     4.3     5.4    -      -       +      -
    414A  LEU*     4.1    13.2    -      -       +      -
    418A  GLU*     2.7    48.7    +      -       +      +
    421A  ALA*     3.9     0.3    -      -       -      +
    422A  LEU*     3.5    26.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 242 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  VAL*     5.7     1.3    -      -       +      -
    179A  ASN*     3.2    38.6    -      -       +      +
    181A  ILE*     3.8    28.5    -      -       +      -
    184A  LEU*     4.0    13.1    -      -       +      +
    238A  LEU*     4.0    20.4    -      -       +      -
    239A  ALA*     2.9    19.1    +      -       +      +
    241A  THR*     1.3    76.3    +      -       -      +
    243A  ALA*     1.3    66.5    +      -       -      +
    244A  VAL      3.3     1.3    -      -       -      -
    245A  ILE*     3.3     6.5    +      -       +      +
    246A  ALA*     3.0    21.9    +      -       +      +
    421A  ALA*     4.2    30.5    -      -       +      +
    425A  ALA*     5.0     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 243 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223A  ALA      5.4     1.6    -      -       -      +
    226A  ALA*     4.2    26.7    -      -       -      +
    227A  MET*     4.5     0.9    -      -       -      -
    230A  GLY*     5.3     2.5    -      -       -      -
    238A  LEU*     4.3     9.3    -      -       +      +
    239A  ALA      3.2    10.0    +      -       -      +
    240A  HIS*     3.2     9.6    +      -       -      +
    242A  ILE*     1.3    77.7    -      -       -      +
    244A  VAL*     1.3    62.1    +      -       -      +
    246A  ALA*     3.3     5.0    +      -       -      +
    247A  ARG*     3.0    20.8    +      -       -      +
    366A  GLN*     3.4    30.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 244 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240A  HIS      3.1    13.5    +      -       -      +
    241A  THR*     3.5    20.9    -      -       -      +
    243A  ALA*     1.3    73.1    -      -       -      +
    245A  ILE*     1.3    64.7    +      -       +      +
    247A  ARG*     3.0     9.2    +      -       +      +
    248A  ALA*     2.9    25.1    +      -       -      +
    365A  PRO*     3.4    22.9    -      -       +      +
    366A  GLN*     3.9    22.2    -      -       -      +
    369A  MET*     3.4    32.9    -      -       +      +
    400A  CYS*     3.8    12.6    -      -       -      -
    404A  ILE*     4.1    14.8    -      -       +      -
    422A  LEU*     5.5     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 245 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181A  ILE*     4.6     9.4    -      -       +      -
    184A  LEU*     5.5     4.3    -      -       +      -
    241A  THR      3.3    20.4    -      -       -      +
    242A  ILE*     3.3    12.5    +      -       +      +
    243A  ALA      3.3     0.4    -      -       -      -
    244A  VAL*     1.3    77.3    -      -       +      +
    246A  ALA*     1.3    64.7    +      -       -      +
    248A  ALA*     3.0    13.8    +      -       -      +
    249A  ILE*     3.1    34.8    +      -       +      +
    397A  ALA*     4.2    14.1    -      -       +      +
    400A  CYS*     4.1    15.0    -      -       -      -
    401A  CYS*     3.9    24.0    -      -       -      -
    422A  LEU*     4.3     5.8    -      -       +      -
    425A  ALA*     3.5    32.1    -      -       +      -
    429A  LEU*     4.5     7.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 246 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172A  PHE*     4.9     1.8    -      -       +      -
    184A  LEU*     4.6    14.5    -      -       +      +
    188A  ILE*     3.9    22.8    -      -       +      +
    223A  ALA*     4.2     7.7    -      -       -      +
    226A  ALA*     4.0    22.4    -      -       +      -
    242A  ILE      3.0    13.1    +      -       -      +
    243A  ALA      3.3     8.7    +      -       -      +
    245A  ILE*     1.3    76.5    -      -       -      +
    247A  ARG*     1.3    61.8    +      -       -      +
    249A  ILE*     3.4     8.7    +      -       -      +
    250A  SER*     3.2    21.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 247 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219A  ASP      5.4     1.0    +      -       -      -
    223A  ALA*     3.5    23.8    +      -       -      +
    224A  ASN*     2.9    31.9    +      -       -      -
    227A  MET*     3.5    35.4    -      -       -      +
    243A  ALA      3.0    13.5    +      -       -      +
    244A  VAL*     3.0    13.2    +      -       +      +
    246A  ALA*     1.3    74.6    -      -       -      +
    248A  ALA*     1.3    65.5    +      -       -      +
    250A  SER*     2.5    25.8    +      -       -      -
    251A  ALA*     3.4     3.5    +      -       -      +
    269A  CYS      4.2     0.4    +      -       -      -
    271A  TYR*     3.6    20.7    -      -       -      +
    272A  GLU*     3.2    38.6    +      -       +      +
    275A  ILE*     4.8     1.0    -      -       +      +
    299A  MET*     4.8     1.4    -      -       -      +
    366A  GLN*     5.2     3.0    +      -       +      +
    369A  MET*     3.7    15.9    -      -       +      -
    370A  LEU*     4.0    19.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 248 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244A  VAL      2.9     9.5    +      -       -      +
    245A  ILE      3.0     8.0    +      -       -      +
    247A  ARG*     1.3    75.4    -      -       -      +
    249A  ILE*     1.3    62.3    +      -       -      +
    251A  ALA*     3.3     8.3    +      -       -      +
    252A  PRO*     3.3    16.1    -      -       -      +
    275A  ILE*     4.8     4.5    -      -       -      -
    369A  MET*     3.4    14.5    -      -       +      +
    378A  VAL*     4.6     3.7    -      -       +      +
    396A  ALA*     3.6    23.2    -      -       +      +
    397A  ALA*     4.3     1.3    -      -       -      -
    400A  CYS*     3.5    32.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 249 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181A  ILE      4.9     1.3    -      -       -      +
    184A  LEU*     4.3     8.7    -      -       +      -
    185A  LEU*     3.8    33.7    -      -       +      +
    188A  ILE*     3.8    12.8    -      -       +      +
    189A  GLY*     3.5    30.9    -      -       -      +
    245A  ILE*     3.1    24.6    +      -       +      +
    246A  ALA*     3.8     6.5    -      -       -      +
    248A  ALA*     1.3    72.6    -      -       -      +
    250A  SER*     1.3    64.1    +      -       -      +
    251A  ALA      3.1     0.2    -      -       -      -
    252A  PRO*     3.1    18.4    -      -       -      +
    253A  ARG*     3.6     5.9    +      -       -      +
    393A  ALA*     4.2    14.4    -      -       +      +
    397A  ALA*     3.8    28.3    -      -       +      -
    429A  LEU*     5.0     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 250 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188A  ILE*     3.7    10.3    -      -       -      -
    219A  ASP*     3.3    34.5    -      -       -      -
    223A  ALA*     3.8     4.0    -      -       -      -
    246A  ALA      3.2    11.3    +      -       -      -
    247A  ARG*     2.5    25.1    +      -       -      -
    249A  ILE*     1.3    74.9    -      -       -      +
    251A  ALA*     1.3    56.2    +      -       -      +
    253A  ARG*     3.2     2.5    +      -       -      +
    254A  SER*     2.8    36.9    +      -       -      -
    272A  GLU*     3.2    19.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 251 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    247A  ARG      4.3     0.2    -      -       -      +
    248A  ALA      3.3    10.6    +      -       -      +
    249A  ILE      3.1     0.4    -      -       -      -
    250A  SER*     1.3    82.3    +      -       -      +
    252A  PRO*     1.4    64.8    -      -       +      +
    254A  SER      3.3     0.2    +      -       -      -
    255A  LEU*     2.9    28.2    +      -       -      +
    272A  GLU*     4.0    13.0    -      -       +      -
    275A  ILE*     3.6    46.0    -      -       +      -
    276A  VAL*     3.8     8.5    -      -       +      +
    279A  ILE*     6.0     0.4    -      -       -      -
    382A  ILE*     4.0     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 252 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    193A  SER*     4.0     2.8    +      -       -      +
    248A  ALA      3.3    12.3    -      -       -      +
    249A  ILE      3.1    20.0    -      -       -      +
    251A  ALA*     1.4    82.7    -      -       +      +
    253A  ARG*     1.3    65.4    +      -       -      +
    255A  LEU*     3.5    14.5    +      -       +      +
    256A  VAL*     3.6     2.4    -      -       -      +
    382A  ILE*     3.8    22.4    -      -       +      -
    389A  ILE      5.3     0.7    -      -       -      +
    392A  ARG*     3.2    49.4    +      -       +      +
    393A  ALA*     3.7    28.7    -      -       +      +
    396A  ALA*     4.4     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 253 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    165A  SER*     3.2    29.1    +      -       -      -
    167A  GLY      5.4     3.8    +      -       -      +
    188A  ILE*     3.4    30.7    -      -       +      +
    189A  GLY*     4.8     0.8    -      -       -      -
    192A  GLY*     3.9    18.7    +      -       -      -
    193A  SER*     3.5    11.1    +      -       -      +
    196A  MET*     3.4    24.8    -      -       +      +
    217A  ASP*     3.1    24.5    +      -       -      +
    218A  THR      3.1    25.9    +      -       -      +
    219A  ASP*     3.1    27.7    +      -       -      +
    222A  GLN*     4.4     2.2    +      -       -      +
    249A  ILE      3.6    10.7    +      -       -      +
    250A  SER      3.2     7.2    +      -       -      +
    252A  PRO*     1.3    81.6    -      -       -      +
    254A  SER*     1.3    82.4    +      -       -      +
    256A  VAL*     3.2    18.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 254 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196A  MET*     3.9     2.0    -      -       -      +
    217A  ASP*     5.2     3.4    -      -       -      +
    218A  THR*     4.0     4.6    -      -       -      -
    219A  ASP      3.4     1.7    +      -       -      -
    250A  SER      2.8    18.0    +      -       -      -
    251A  ALA      4.0     2.2    -      -       -      -
    253A  ARG*     1.3    96.1    +      -       -      +
    255A  LEU*     1.3    64.6    +      -       -      +
    256A  VAL      3.0     1.0    +      -       -      -
    257A  ALA*     3.3    14.0    +      -       -      +
    258A  TYR*     3.5    17.8    -      -       -      -
    272A  GLU*     2.7    33.2    +      -       -      -
    273A  ASN*     5.2     4.0    -      -       -      -
    276A  VAL*     4.4     6.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 255 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  TYR*     3.9    11.7    -      -       +      -
    251A  ALA      2.9    17.9    +      -       -      +
    252A  PRO*     3.5     7.0    -      -       +      +
    253A  ARG      3.2     0.2    -      -       -      -
    254A  SER*     1.3    76.9    -      -       -      +
    256A  VAL*     1.3    60.9    +      -       -      +
    258A  TYR*     3.1    17.8    +      -       -      +
    259A  GLU*     3.2    31.1    +      -       -      +
    276A  VAL*     4.2    10.2    -      -       +      +
    279A  ILE*     3.9    37.7    -      -       +      -
    280A  THR*     3.5    31.9    -      -       +      -
    382A  ILE*     4.2    11.2    -      -       +      -
    392A  ARG*     3.8    14.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 256 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  ARG*     3.8    15.7    -      -       -      +
    193A  SER*     3.8    21.8    -      -       -      +
    196A  MET*     3.6     8.1    -      -       +      +
    197A  GLU*     3.4    44.0    -      -       +      +
    252A  PRO      3.6     3.1    -      -       -      +
    253A  ARG      3.4    15.5    -      -       -      +
    254A  SER      3.0     1.6    +      -       -      -
    255A  LEU*     1.3    74.9    -      -       -      +
    257A  ALA*     1.3    55.2    +      -       -      +
    259A  GLU*     3.1     8.7    +      -       +      +
    260A  ALA*     2.8    34.8    +      -       +      +
    392A  ARG*     3.5    22.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 257 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196A  MET*     3.6    22.6    -      -       +      +
    200A  TRP*     3.7    34.2    -      -       +      +
    217A  ASP      4.4     7.9    -      -       -      +
    254A  SER      3.3     8.8    +      -       -      +
    255A  LEU      3.3     0.4    -      -       -      -
    256A  VAL*     1.3    76.0    -      -       -      +
    258A  TYR*     1.3    65.6    +      -       +      +
    260A  ALA*     3.3     4.2    +      -       -      +
    261A  GLY      3.1     9.2    +      -       -      -
    262A  ALA*     2.8    29.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 258 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  TYR*     4.5     7.8    +      -       +      -
    215A  ALA      3.3    21.1    -      -       -      -
    216A  GLY*     3.5    12.4    -      -       -      -
    217A  ASP      4.1     5.9    +      -       -      -
    254A  SER*     3.5    24.0    -      -       -      -
    255A  LEU*     3.1     8.8    +      -       -      +
    257A  ALA*     1.3    73.9    -      -       +      +
    259A  GLU*     1.3    68.1    +      -       -      +
    260A  ALA      3.0     1.1    -      -       -      -
    261A  GLY*     3.0    12.0    +      -       -      -
    262A  ALA*     3.5    22.5    -      -       +      +
    264A  GLY*     3.7     9.6    -      -       -      -
    266A  GLY*     3.1    28.4    -      -       -      -
    273A  ASN*     4.6     2.8    +      -       -      -
    276A  VAL*     3.6    25.6    -      -       +      -
    280A  THR*     4.0    14.1    -      -       +      -
    282A  MET*     3.6    33.7    -      -       +      +
    284A  MET*     3.8    12.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 259 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  ALA*     3.8     7.5    -      -       -      +
      4A  LYS*     3.3    48.6    +      -       -      +
      5A  ARG*     3.3    20.8    +      -       -      +
      6A  TYR*     2.9    35.5    +      -       +      -
    255A  LEU*     3.2    15.8    +      -       -      +
    256A  VAL*     3.1    12.1    +      -       -      +
    258A  TYR*     1.3    76.3    -      -       -      +
    260A  ALA*     1.3    57.7    +      -       -      +
    261A  GLY      3.4     2.1    +      -       -      -
    392A  ARG*     2.6    46.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 260 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  ALA*     4.1    19.7    -      -       +      +
    197A  GLU*     4.4    10.3    -      -       +      +
    200A  TRP*     3.4    21.6    -      -       +      +
    201A  THR*     4.0    22.3    +      -       -      +
    204A  SER*     3.4    13.3    +      -       -      -
    256A  VAL      2.8    16.7    +      -       -      +
    257A  ALA      3.4     6.7    -      -       -      +
    258A  TYR      3.0     0.2    -      -       -      -
    259A  GLU*     1.3    76.0    -      -       -      +
    261A  GLY*     1.3    56.2    +      -       -      +
----------------------------------------------------------
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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