Contacts of the helix formed by residues 213 - 243 (chain A) in PDB entry 2LCK


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 ASP 213 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  THR*     3.3    20.2    -      -       +      +
    212A  ASP*     1.3    80.1    -      -       -      +
    214A  LEU*     1.3    62.2    +      -       -      +
    215A  PRO*     3.4     8.5    -      -       +      -
    216A  CYS*     2.7    49.1    -      -       +      +
    217A  HIS*     3.6     2.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 214 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    209A  LEU*     4.6    16.8    -      -       +      -
    211A  THR      3.4    22.4    -      -       -      +
    212A  ASP*     3.0    11.6    +      -       -      +
    213A  ASP*     1.3    72.6    -      -       -      +
    215A  PRO*     1.3    70.5    -      -       +      +
    217A  HIS*     2.5    44.8    +      -       +      +
    218A  PHE*     3.1     8.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 215 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    212A  ASP      4.8     1.1    -      -       -      +
    213A  ASP*     3.4     6.7    -      -       +      -
    214A  LEU*     1.3    96.5    -      -       +      +
    216A  CYS*     1.3    63.1    +      -       +      +
    218A  PHE*     3.4    10.7    +      -       +      +
    219A  THR*     3.0    27.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with CYS 216 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     6.2     0.2    -      -       -      -
    211A  THR*     5.0     7.2    -      -       -      -
    213A  ASP*     2.7    44.6    +      -       +      +
    214A  LEU      3.1     0.4    -      -       -      -
    215A  PRO*     1.3    84.7    -      -       +      +
    217A  HIS*     1.3    74.6    +      -       -      +
    219A  THR*     3.6     6.0    +      -       -      -
    220A  SER*     3.4    19.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 217 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     3.6    43.4    -      -       +      +
    209A  LEU*     5.0    11.6    -      -       +      +
    211A  THR*     6.6     0.2    -      -       -      -
    213A  ASP      4.1     0.9    +      -       -      +
    214A  LEU*     2.5    42.9    +      -       +      +
    216A  CYS*     1.3    89.2    -      -       -      +
    218A  PHE*     1.3   124.3    +      +       -      +
    220A  SER*     2.4    28.7    +      -       -      -
    221A  ALA*     3.2     7.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 218 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    214A  LEU*     3.1    16.6    +      -       +      -
    215A  PRO*     3.4    11.2    +      -       +      +
    216A  CYS      3.3     0.4    -      -       -      -
    217A  HIS*     1.3   120.2    -      +       -      +
    219A  THR*     1.3    66.3    +      -       -      +
    221A  ALA*     2.9    20.0    +      -       +      +
    222A  PHE*     3.2    11.8    +      -       -      +
    291A  TYR*     5.7     9.0    -      +       -      -
    294A  LEU*     4.3    39.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 219 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215A  PRO*     3.0    15.8    +      -       -      +
    216A  CYS*     4.0     6.4    -      -       -      -
    217A  HIS      3.4     0.2    -      -       -      -
    218A  PHE*     1.3    76.5    -      -       -      +
    220A  SER*     1.3    64.2    +      -       -      +
    221A  ALA      3.3     0.3    +      -       -      -
    222A  PHE*     3.3    15.9    +      -       +      +
    223A  GLY*     3.4     9.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 220 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     5.6     2.4    -      -       -      +
    216A  CYS      3.4    10.0    +      -       -      -
    217A  HIS*     2.4    29.3    +      -       -      +
    218A  PHE      3.2     0.2    -      -       -      -
    219A  THR*     1.3    79.7    -      -       -      +
    221A  ALA*     1.3    62.7    +      -       -      +
    223A  GLY*     3.6     1.0    +      -       -      -
    224A  ALA*     3.1    23.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 221 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    217A  HIS*     3.9     7.9    -      -       +      +
    218A  PHE*     2.9    18.4    +      -       +      +
    220A  SER*     1.3    84.4    +      -       -      +
    222A  PHE*     1.3    50.4    +      -       -      +
    224A  ALA*     3.1     8.6    +      -       -      +
    225A  GLY*     2.3    35.7    +      -       -      -
    291A  TYR*     5.3    14.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 222 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    218A  PHE      3.2     8.1    +      -       -      +
    219A  THR*     3.3    11.8    +      -       +      +
    221A  ALA*     1.3    74.4    -      -       -      +
    223A  GLY*     1.3    65.7    +      -       -      +
    225A  GLY*     2.8    16.6    +      -       -      +
    226A  PHE*     3.0    19.7    +      +       +      +
    288A  PHE*     5.9     7.6    -      +       -      -
    291A  TYR*     6.3     4.9    -      +       -      -
----------------------------------------------------------
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Residues in contact with GLY 223 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219A  THR      3.4     8.9    +      -       -      -
    220A  SER      4.1     2.2    -      -       -      -
    221A  ALA      3.3     0.2    -      -       -      -
    222A  PHE*     1.3    84.6    -      -       -      +
    224A  ALA*     1.3    61.8    +      -       -      +
    226A  PHE*     3.4    12.7    +      -       -      +
    227A  CYS*     3.6    16.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 224 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    220A  SER      3.1    16.9    +      -       -      +
    221A  ALA*     3.1    15.0    -      -       -      +
    223A  GLY*     1.3    77.8    -      -       -      +
    225A  GLY*     1.3    58.3    +      -       -      +
    227A  CYS*     3.2    10.7    +      -       -      +
    228A  THR*     3.2    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 225 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    221A  ALA      2.3    24.1    +      -       -      -
    222A  PHE*     2.8     8.5    +      -       -      -
    224A  ALA*     1.3    67.2    -      -       -      +
    226A  PHE*     1.3    61.4    +      -       -      -
    228A  THR*     2.7    28.1    -      -       -      +
    229A  THR*     3.3    15.0    +      -       -      +
    291A  TYR*     5.6     5.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 226 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  PHE*     3.0    16.9    +      +       +      +
    223A  GLY*     3.8     9.2    -      -       -      +
    224A  ALA      3.3     0.4    -      -       -      -
    225A  GLY*     1.3    77.4    -      -       -      +
    227A  CYS*     1.3    67.4    +      -       -      +
    229A  THR*     2.3    29.9    +      -       +      -
    230A  VAL*     3.6    19.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 227 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223A  GLY      3.7    13.5    -      -       -      -
    224A  ALA*     3.2    11.5    +      -       -      +
    226A  PHE*     1.3    83.8    -      -       -      +
    228A  THR*     1.3    62.1    +      -       -      +
    230A  VAL*     3.3    16.4    +      -       -      +
    231A  ILE*     3.3    18.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 228 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196A  THR*     5.4     8.4    -      -       -      +
    224A  ALA      3.2    13.3    +      -       -      +
    225A  GLY*     2.7    33.7    -      -       -      +
    227A  CYS*     1.3    73.2    -      -       -      +
    229A  THR*     1.3    69.1    +      -       +      +
    231A  ILE*     2.9    14.9    +      -       -      +
    232A  ALA*     2.8    21.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 229 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225A  GLY      3.3    13.5    -      -       -      +
    226A  PHE*     2.3    41.1    +      -       +      -
    228A  THR*     1.3    78.9    -      -       +      +
    230A  VAL*     1.3    61.1    +      -       -      +
    232A  ALA*     2.9    19.5    +      -       +      +
    233A  SER*     2.7    20.6    +      -       -      -
    280A  LEU*     6.2     4.3    -      -       +      -
    283A  TRP*     5.3     3.1    -      -       +      -
    284A  ASN*     5.4     0.9    -      -       -      +
    287A  MET*     3.8    30.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 230 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  PHE*     3.8    30.5    -      -       +      +
    227A  CYS*     3.3    10.3    +      -       -      +
    228A  THR      3.1     0.6    -      -       -      -
    229A  THR*     1.3    78.1    +      -       -      +
    231A  ILE*     1.3    69.0    +      -       +      +
    233A  SER*     3.2    18.3    +      -       -      +
    234A  PRO*     3.3    12.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 231 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196A  THR*     4.5    21.1    -      -       +      +
    199A  LEU*     6.5     0.7    -      -       +      -
    227A  CYS      3.3    17.0    -      -       -      +
    228A  THR*     2.9    16.1    +      -       -      +
    230A  VAL*     1.3    85.5    -      -       +      +
    232A  ALA*     1.3    55.5    +      -       -      +
    234A  PRO*     2.7    26.3    -      -       -      +
    235A  VAL*     6.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 232 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228A  THR*     2.8    13.8    +      -       -      +
    229A  THR*     3.1    18.4    -      -       +      +
    231A  ILE*     1.3    73.9    -      -       -      +
    233A  SER*     1.3    55.2    +      -       -      +
    234A  PRO*     3.1     6.7    -      -       -      -
    235A  VAL*     3.0    30.9    -      -       -      +
    236A  ASP*     3.3     5.6    -      -       -      +
    283A  TRP*     4.5    24.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 233 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    229A  THR      2.7    16.8    +      -       -      -
    230A  VAL*     3.2    15.7    +      -       -      -
    232A  ALA*     1.3    73.2    -      -       -      +
    234A  PRO*     1.3    66.8    -      -       -      +
    236A  ASP*     3.0    15.9    +      -       -      +
    237A  VAL*     3.0    21.7    +      -       -      +
    280A  LEU*     4.6    20.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 234 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  VAL      3.3    10.1    -      -       -      +
    231A  ILE*     2.7    32.3    -      -       -      +
    232A  ALA      3.1     2.0    -      -       -      +
    233A  SER*     1.3    81.6    -      -       -      +
    235A  VAL*     1.3    67.4    +      -       +      +
    236A  ASP      3.2     0.3    +      -       -      -
    237A  VAL*     3.2    28.9    +      -       +      +
    238A  VAL*     3.4    11.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 235 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185A  ARG*     5.7     3.6    -      -       -      +
    188A  ILE*     4.6    22.9    -      -       +      -
    189A  VAL*     5.1    14.6    -      -       +      -
    192A  ALA*     5.4     8.3    -      -       +      -
    231A  ILE      5.2     0.4    +      -       -      +
    232A  ALA*     3.0    22.7    -      -       -      +
    234A  PRO*     1.3    77.3    -      -       +      +
    236A  ASP*     1.3    70.1    +      -       -      +
    238A  VAL*     3.9     4.4    +      -       -      +
    239A  LYS*     3.2    36.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 236 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185A  ARG*     5.9     1.0    +      -       -      -
    232A  ALA      3.3    18.3    -      -       -      +
    233A  SER*     3.0    13.2    +      -       -      +
    235A  VAL*     1.3    85.9    -      -       -      +
    237A  VAL*     1.3    57.1    +      -       -      +
    239A  LYS*     3.6    16.1    +      -       -      +
    276A  SER*     2.7    34.3    +      -       -      +
    279A  ARG*     6.2     2.7    -      -       +      -
    280A  LEU*     5.3    10.0    -      -       +      +
    283A  TRP*     5.0    25.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 237 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233A  SER*     3.0    13.0    +      -       -      +
    234A  PRO*     3.2    22.1    +      -       +      +
    236A  ASP*     1.3    74.7    -      -       -      +
    238A  VAL*     1.3    74.4    +      -       +      +
    240A  THR*     2.7    27.7    -      -       +      +
    241A  ARG*     3.8     6.4    +      -       -      +
    269A  PHE*     5.1    11.0    -      -       +      +
    273A  PHE*     4.7    18.2    -      -       +      -
    276A  SER*     4.1     4.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 238 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    234A  PRO*     3.4    16.7    +      -       +      +
    235A  VAL*     4.3     4.5    -      -       -      +
    236A  ASP      3.5     0.2    -      -       -      -
    237A  VAL*     1.3    90.6    -      -       +      +
    239A  LYS*     1.3    65.5    +      -       +      +
    240A  THR      3.5     0.2    +      -       -      -
    241A  ARG*     3.5    20.8    +      -       +      +
    242A  TYR*     3.9     3.8    +      -       -      +
    269A  PHE*     5.1    22.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 239 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185A  ARG*     3.7    40.8    -      -       -      +
    188A  ILE*     6.2     1.5    -      -       -      +
    235A  VAL*     3.2    27.7    +      -       -      +
    236A  ASP*     3.7     9.8    +      -       -      +
    237A  VAL      3.2     0.4    -      -       -      -
    238A  VAL*     1.3    81.6    -      -       +      +
    240A  THR*     1.3    63.0    +      -       -      +
    242A  TYR*     3.2    22.9    -      -       -      +
    243A  MET*     4.4     1.2    +      -       -      +
    276A  SER*     5.1     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 240 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    236A  ASP      3.8     0.8    +      -       -      -
    237A  VAL*     2.7    29.4    -      -       -      +
    239A  LYS*     1.3    73.2    -      -       -      +
    241A  ARG*     1.3    66.4    +      -       +      +
    242A  TYR      3.0     1.0    +      -       -      -
    243A  MET*     3.0    26.7    +      -       -      +
    272A  GLY      4.3     4.4    +      -       -      +
    273A  PHE*     4.0    17.3    +      -       +      -
    275A  PRO*     3.4    28.8    -      -       -      +
    276A  SER*     2.9    38.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 241 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    237A  VAL      4.4     7.4    -      -       -      +
    238A  VAL*     3.5    13.2    +      -       +      +
    239A  LYS      3.3     0.2    -      -       -      -
    240A  THR*     1.3    82.1    -      -       -      +
    242A  TYR*     1.3    58.4    +      -       -      +
    244A  ASN*     2.5    56.6    +      -       -      +
    260A  MET*     5.1     2.8    -      -       -      +
    264A  GLU*     4.8    10.5    +      -       -      +
    265A  GLY      4.8     0.8    +      -       -      -
    268A  ALA*     3.2    48.8    +      -       -      +
    269A  PHE*     3.3    59.8    -      -       +      +
    271A  LYS      4.3     3.6    -      -       -      -
    272A  GLY*     4.2    13.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 242 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238A  VAL      3.9     3.3    +      -       -      +
    239A  LYS*     3.2    17.8    +      -       -      +
    241A  ARG*     1.3    77.2    -      -       -      +
    243A  MET*     1.3    70.6    +      -       +      +
    244A  ASN*     2.3    28.3    +      -       -      +
    245A  SER*     2.7    39.5    +      -       -      +
    246A  ALA*     3.4    23.1    -      -       +      +
    247A  LEU*     4.0    10.3    +      -       -      +
    250A  TYR*     5.8     6.1    -      +       -      -
----------------------------------------------------------
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Residues in contact with MET 243 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  LYS*     5.7     8.1    -      -       -      +
     41A  LEU      6.0     2.2    -      -       -      +
     42A  GLN*     5.0    22.7    -      -       -      +
    239A  LYS      4.4     0.9    +      -       -      +
    240A  THR*     3.0    23.0    +      -       -      +
    242A  TYR*     1.3    89.6    -      -       +      +
    244A  ASN*     1.3    52.8    +      -       -      +
    245A  SER*     2.4    23.5    +      -       -      +
    275A  PRO*     5.3    11.0    -      -       +      -
----------------------------------------------------------
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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
------------------------------------------------------------
  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