Contacts of the helix formed by residues 241 - 268 (chain A) in PDB entry 4GL5


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 TYR 241 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  CYS*     5.0    10.3    -      -       -      -
    227A  LEU*     4.3     5.6    -      -       +      -
    234A  PHE*     3.6    36.1    -      +       +      -
    235A  PHE*     3.0    54.3    +      +       -      +
    237A  ILE      4.4     0.2    -      -       -      -
    238A  SER*     3.8    27.2    -      -       -      -
    240A  LEU*     1.3    80.7    -      -       -      +
    242A  LYS*     1.3    67.1    +      -       +      +
    243A  LYS*     3.1     4.0    -      -       -      +
    244A  TYR*     2.9    19.8    +      -       +      +
    245A  GLU*     2.9    48.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 242 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238A  SER*     3.4    36.7    +      -       -      +
    239A  TRP*     4.0    28.2    -      -       +      +
    240A  LEU      3.9     0.6    -      -       -      +
    241A  TYR*     1.3    77.9    -      -       -      +
    243A  LYS*     1.3    62.7    +      -       -      +
    245A  GLU*     3.3    17.8    +      -       -      +
    246A  LYS*     3.0    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 243 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239A  TRP      5.1     8.7    +      -       -      +
    240A  LEU*     4.4    20.5    +      -       -      +
    241A  TYR*     4.7     1.8    -      -       -      +
    242A  LYS*     1.3    79.7    -      -       -      +
    244A  TYR*     1.3    82.2    +      -       +      +
    246A  LYS*     3.1    20.7    +      -       -      +
    247A  SER*     3.1    18.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 244 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  CYS*     5.4     0.2    -      -       -      -
    219A  GLY      5.6     0.2    -      -       -      -
    222A  ASP*     4.4    10.3    -      -       +      -
    223A  ALA*     3.7    30.5    -      -       +      +
    226A  ALA*     3.5    26.0    -      -       +      +
    227A  LEU*     3.7    34.8    -      -       +      -
    230A  LYS*     5.2     4.3    +      -       -      -
    234A  PHE*     4.7     5.8    -      +       -      -
    240A  LEU      4.3    11.2    -      -       -      -
    241A  TYR*     2.9    19.1    +      -       -      +
    243A  LYS*     1.3    94.7    -      -       +      +
    245A  GLU*     1.3    64.8    +      -       -      +
    247A  SER*     3.5     4.4    +      -       -      +
    248A  VAL*     3.3    29.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 245 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  CYS*     4.4    21.6    -      -       -      +
    241A  TYR*     2.9    42.0    +      -       +      +
    242A  LYS*     3.3    18.7    +      -       +      +
    244A  TYR*     1.3    77.1    -      -       -      +
    246A  LYS*     1.3    60.1    +      -       -      +
    248A  VAL*     4.0     4.7    -      -       -      +
    249A  LYS*     3.5    19.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 246 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    242A  LYS      3.0    15.7    +      -       -      +
    243A  LYS*     3.1     6.9    +      -       -      +
    245A  GLU*     1.3    78.1    -      -       -      +
    247A  SER*     1.3    60.5    +      -       -      +
    248A  VAL      3.3     0.4    -      -       -      -
    249A  LYS*     3.8    12.7    -      -       +      +
    250A  ASP*     3.1    52.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 247 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216A  LYS*     4.6     2.3    -      -       -      +
    219A  GLY*     3.6    32.8    +      -       -      -
    220A  TYR      4.4     7.3    +      -       -      -
    223A  ALA*     4.7     0.7    -      -       -      -
    243A  LYS*     3.1    16.8    +      -       -      +
    244A  TYR*     3.5     9.7    +      -       -      -
    246A  LYS*     1.3    75.5    +      -       -      +
    248A  VAL*     1.3    65.6    +      -       -      +
    250A  ASP*     3.6    10.0    -      -       -      +
    251A  LEU*     3.5    18.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 248 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  CYS*     3.6    19.7    -      -       -      +
    125A  ILE*     3.9    41.7    -      -       +      +
    220A  TYR*     4.1    21.1    -      -       +      -
    223A  ALA*     4.3     6.7    -      -       +      -
    244A  TYR      3.3    17.2    +      -       -      +
    245A  GLU*     4.0     6.3    -      -       -      +
    247A  SER*     1.3    74.4    -      -       -      +
    249A  LYS*     1.3    67.5    +      -       -      +
    251A  LEU*     3.2     5.9    +      -       -      +
    252A  LYS*     2.9    34.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 249 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    245A  GLU      3.5    16.2    +      -       -      +
    246A  LYS*     3.8    14.4    -      -       +      +
    248A  VAL*     1.3    80.5    -      -       -      +
    250A  ASP*     1.3    56.8    +      -       -      +
    252A  LYS*     4.4     5.8    -      -       -      -
    253A  ASP*     2.7    66.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 250 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216A  LYS*     4.0    31.0    +      -       +      +
    246A  LYS*     3.1    47.9    +      -       -      +
    247A  SER*     3.6    10.6    -      -       -      +
    249A  LYS*     1.3    76.8    -      -       -      +
    251A  LEU*     1.3    62.0    +      -       -      +
    253A  ASP*     4.0     3.8    -      -       -      +
    254A  ALA*     3.1    24.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 251 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    213A  ILE*     4.2    12.6    -      -       +      -
    216A  LYS*     3.9    17.2    -      -       +      +
    217A  ILE*     3.7    32.3    -      -       +      +
    220A  TYR*     3.7    33.2    -      -       +      -
    247A  SER      3.5     7.2    +      -       -      +
    248A  VAL      3.2     7.1    +      -       -      +
    250A  ASP*     1.3    75.3    -      -       -      +
    252A  LYS*     1.3    58.8    +      -       -      +
    254A  ALA*     3.2     4.9    +      -       -      +
    255A  ILE*     2.9    47.0    +      -       +      +
    301A  LEU*     3.8    17.3    -      -       +      -
    305A  ILE*     3.8    20.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 252 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125A  ILE      3.6    17.8    +      -       -      -
    126A  GLY*     3.9     9.1    -      -       -      -
    130A  LYS*     4.5     9.6    -      -       -      +
    248A  VAL*     2.9    27.6    +      -       +      +
    249A  LYS*     3.8     5.4    -      -       -      +
    251A  LEU*     1.3    77.6    -      -       -      +
    253A  ASP*     1.3    60.8    +      -       -      +
    255A  ILE*     3.2     2.9    +      -       -      +
    256A  GLU*     2.8    52.6    +      -       -      +
    297A  ASN*     5.3     7.2    -      -       -      -
    298A  GLN*     3.2    26.1    +      -       -      +
    301A  LEU*     4.0    21.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 253 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249A  LYS*     2.7    61.6    +      -       -      +
    250A  ASP*     4.0     3.8    -      -       -      +
    252A  LYS*     1.3    77.9    -      -       -      +
    254A  ALA*     1.3    61.8    +      -       -      +
    256A  GLU*     3.7     7.9    +      -       -      +
    257A  VAL*     3.5    24.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 254 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    213A  ILE*     3.8    24.9    -      -       +      +
    216A  LYS*     4.3    15.3    -      -       +      +
    250A  ASP      3.1    18.0    +      -       -      +
    251A  LEU*     3.2     7.6    +      -       -      +
    253A  ASP*     1.3    78.9    -      -       -      +
    255A  ILE*     1.3    60.0    +      -       +      +
    257A  VAL*     3.6    17.5    -      -       -      +
    258A  LEU*     3.2    17.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 255 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    213A  ILE*     5.5     4.9    -      -       +      -
    251A  LEU*     2.9    45.3    +      -       +      +
    252A  LYS*     3.9     4.5    -      -       -      +
    254A  ALA*     1.3    77.2    -      -       +      +
    256A  GLU*     1.3    61.9    +      -       -      +
    257A  VAL      3.0     2.0    -      -       -      -
    258A  LEU*     2.8    32.9    +      -       +      +
    259A  ILE*     2.8    21.2    +      -       +      +
    297A  ASN      4.7     5.8    -      -       -      +
    300A  ILE*     4.3    24.2    -      -       +      -
    301A  LEU*     3.8    33.7    -      -       +      +
    304A  LEU*     4.5    17.3    -      -       +      -
    305A  ILE*     5.5     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 256 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  LYS*     2.8    42.5    +      -       -      +
    253A  ASP*     3.7    10.0    +      -       -      +
    255A  ILE*     1.3    74.8    -      -       -      +
    257A  VAL*     1.3    55.0    +      -       +      +
    259A  ILE*     3.4    16.9    -      -       +      +
    260A  ALA*     3.1    28.9    +      -       -      +
    297A  ASN*     3.2    38.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 257 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253A  ASP      3.5    12.2    +      -       -      +
    254A  ALA*     3.6    14.4    -      -       -      +
    255A  ILE      3.0     0.2    -      -       -      -
    256A  GLU*     1.3    79.3    -      -       -      +
    258A  LEU*     1.3    66.1    +      -       +      +
    260A  ALA*     3.6     6.7    +      -       -      +
    261A  GLU*     3.4    20.1    +      -       -      +
    264A  ARG*     5.1     1.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 258 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     3.9    20.0    -      -       +      -
    206A  ILE*     3.8    32.9    -      -       +      +
    207A  PRO      4.1     2.0    -      -       -      +
    208A  LEU*     3.7    44.0    -      -       +      -
    213A  ILE*     4.6    12.1    -      -       +      -
    254A  ALA      3.2    21.5    -      -       -      +
    255A  ILE*     2.8    26.5    +      -       +      +
    257A  VAL*     1.3    81.0    -      -       +      +
    259A  ILE*     1.3    60.0    +      -       +      +
    261A  GLU*     3.2     5.9    +      -       -      +
    262A  LYS*     3.0    25.4    +      -       -      +
    304A  LEU*     5.6     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 259 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     5.0     5.2    -      -       +      -
    255A  ILE*     2.8    27.3    +      -       +      +
    256A  GLU*     3.4    28.5    -      -       +      +
    258A  LEU*     1.3    70.6    -      -       +      +
    260A  ALA*     1.3    66.3    +      -       +      +
    262A  LYS*     3.7     8.6    -      -       +      +
    263A  ARG*     3.0    56.2    +      -       -      +
    283A  ILE*     5.0     3.5    -      -       +      +
    293A  ARG*     6.3     0.2    -      -       -      -
    297A  ASN*     3.6    29.4    -      -       -      +
    300A  ILE*     3.6    47.6    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
    256A  GLU      3.1    21.5    +      -       -      +
    257A  VAL*     3.7     8.7    -      -       -      +
    258A  LEU      3.1     0.4    -      -       -      -
    259A  ILE*     1.3    81.8    -      -       +      +
    261A  GLU*     1.3    60.4    +      -       -      +
    263A  ARG*     3.4    15.9    +      -       -      +
    264A  ARG*     3.4    35.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 261 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    206A  ILE*     4.1    15.7    -      -       +      -
    257A  VAL      3.4     9.0    +      -       -      +
    258A  LEU*     3.2     7.2    +      -       -      +
    260A  ALA*     1.3    76.2    -      -       -      +
    262A  LYS*     1.3    66.7    +      -       -      +
    263A  ARG      3.3     0.2    +      -       -      -
    264A  ARG*     2.6    49.2    +      -       -      +
    265A  ARG*     2.8    65.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 262 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     3.1    36.6    +      -       +      +
    205A  ARG*     3.9    13.3    +      -       -      +
    206A  ILE*     3.8    20.1    -      -       +      +
    258A  LEU      3.0    14.6    +      -       -      +
    259A  ILE*     3.3    11.0    +      -       +      +
    261A  GLU*     1.3    77.8    -      -       -      +
    263A  ARG*     1.3    58.5    +      -       -      +
    265A  ARG*     3.5     7.3    +      -       +      +
    266A  ILE*     3.0    33.7    +      -       +      +
    277A  ASP*     3.1    36.5    +      -       -      -
    279A  ALA*     4.2     5.8    -      -       +      -
    280A  THR*     3.5    11.7    +      -       -      -
    283A  ILE*     4.0    17.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 263 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    259A  ILE*     3.0    49.8    +      -       -      +
    260A  ALA*     3.7     7.7    -      -       -      +
    261A  GLU      3.2     0.2    -      -       -      -
    262A  LYS*     1.3    75.6    -      -       -      +
    264A  ARG*     1.3    64.2    +      -       -      +
    266A  ILE*     3.3     8.0    +      -       -      +
    267A  SER*     3.1    24.8    +      -       -      -
    283A  ILE*     4.0    31.4    -      -       +      +
    286A  GLU*     2.6    36.0    +      -       -      -
    287A  LYS*     5.5     4.6    -      -       -      +
    293A  ARG*     3.8    18.7    -      -       -      +
    296A  VAL*     4.1     9.9    -      -       -      +
    297A  ASN*     3.6    15.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 264 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    257A  VAL      5.1     1.4    +      -       -      -
    260A  ALA*     3.4    32.3    +      -       -      +
    261A  GLU*     2.6    54.7    +      -       -      +
    263A  ARG*     1.3    76.1    -      -       +      +
    265A  ARG*     1.3    64.5    +      -       +      +
    266A  ILE      3.1     0.2    +      -       -      -
    267A  SER*     2.9    24.2    +      -       -      -
    268A  THR*     3.3    15.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 265 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    205A  ARG      4.1     4.8    +      -       -      -
    206A  ILE*     3.6    26.5    -      -       +      +
    207A  PRO*     3.7    32.1    -      -       -      +
    261A  GLU*     2.8    46.2    +      -       -      +
    262A  LYS*     3.9    11.2    -      -       +      +
    263A  ARG      3.3     0.4    -      -       -      -
    264A  ARG*     1.3    76.2    -      -       +      +
    266A  ILE*     1.3    60.2    +      -       +      +
    268A  THR*     3.8    15.3    -      -       -      +
    269A  GLU*     3.0    16.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 266 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    262A  LYS*     3.0    25.6    -      -       +      +
    263A  ARG*     4.1     3.8    -      -       -      +
    264A  ARG      3.1     0.6    -      -       -      -
    265A  ARG*     1.3    76.4    -      -       +      +
    267A  SER*     1.3    63.0    +      -       -      +
    268A  THR      3.1     5.9    +      -       -      -
    269A  GLU*     3.3    34.7    -      -       +      +
    272A  LEU*     5.5     5.5    -      -       +      +
    280A  THR*     3.8    39.0    -      -       +      +
    283A  ILE*     3.8    37.9    -      -       +      -
    284A  LEU*     4.9    14.6    -      -       +      -
    287A  LYS*     6.3     4.0    -      -       -      -
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Residues in contact with SER 267 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    263A  ARG      3.1    14.0    +      -       -      -
    264A  ARG*     2.9    23.2    +      -       -      -
    266A  ILE*     1.3    76.5    -      -       -      +
    268A  THR*     1.3    64.3    +      -       -      +
    269A  GLU      3.8     1.5    +      -       -      -
    287A  LYS*     5.7     8.7    -      -       -      +
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Residues in contact with THR 268 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    264A  ARG*     3.3    16.4    +      -       +      +
    265A  ARG*     3.8    12.2    +      -       -      +
    266A  ILE      3.1     0.6    -      -       -      -
    267A  SER*     1.3    85.6    -      -       -      +
    269A  GLU*     1.3    60.3    +      -       -      +
    270A  GLU      4.0     1.0    +      -       -      -
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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
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  Atomic class           I  II  III   IV   V   VI  VII  VIII
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   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
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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