Contacts of the helix formed by residues 268 - 291 (chain A) in PDB entry 5A86


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 PRO 268 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    266A  ASP      4.4     1.6    -      -       -      +
    267A  LEU*     1.4    92.6    -      -       +      +
    269A  ILE*     1.3    66.1    +      -       -      +
    270A  GLU*     3.3    28.5    -      -       +      +
    271A  ASP*     3.0    28.7    +      -       -      +
    272A  GLN*     3.0    10.6    +      -       -      +
    357A  LEU*     6.2     0.2    -      -       +      -
    358A  GLN*     3.8    25.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 269 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  LEU      3.6     1.4    +      -       -      -
    268A  PRO*     1.3    72.5    -      -       +      +
    270A  GLU*     1.3    67.3    +      -       +      +
    272A  GLN*     3.3    20.0    +      -       -      +
    273A  ILE*     3.1    31.0    +      -       +      +
    684C  THR*     4.2    15.7    -      -       +      -
    691C  HIS*     4.1    22.0    -      -       +      +
    694C  LEU*     4.0    21.8    -      -       +      -
    695C  GLN*     3.3    33.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 270 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  PRO*     3.2    23.2    -      -       +      +
    269A  ILE*     1.3    83.8    -      -       +      +
    271A  ASP*     1.4    68.7    +      -       -      +
    273A  ILE*     3.4     5.6    +      -       -      -
    274A  SER*     3.0    31.2    +      -       -      -
    355A  GLY      5.4     2.0    -      -       -      +
    357A  LEU*     3.4    31.5    -      -       +      +
    683C  LEU*     3.3    25.9    -      -       +      +
    684C  THR*     5.2     4.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 271 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  LEU*     4.3    11.6    -      -       +      +
    268A  PRO*     3.0    24.4    +      -       +      +
    270A  GLU*     1.4    85.0    -      -       -      +
    272A  GLN*     1.3    59.5    +      -       -      +
    274A  SER*     3.2     5.5    +      -       -      -
    275A  LEU*     2.8    38.9    +      -       +      +
    355A  GLY      4.2     0.7    -      -       -      +
    356A  VAL*     3.9    11.4    -      -       +      +
    357A  LEU*     3.1    30.7    +      -       -      +
    358A  GLN*     3.0    40.0    +      -       -      +
    362A  VAL*     5.0     0.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 272 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    259A  LYS*     5.6     1.6    -      -       -      +
    264A  PHE*     3.4    57.2    -      -       +      +
    265A  ARG*     3.2    19.3    -      -       -      +
    267A  LEU*     3.0    20.1    -      -       +      +
    268A  PRO      3.0    12.0    +      -       -      +
    269A  ILE*     3.4    24.2    +      -       -      +
    271A  ASP*     1.3    74.5    -      -       -      +
    273A  ILE*     1.3    62.9    +      -       -      +
    275A  LEU*     3.4     0.6    +      -       -      -
    276A  LEU*     3.0    28.1    +      -       -      +
    694C  LEU*     3.7    23.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 273 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269A  ILE*     3.1    21.2    +      -       +      +
    270A  GLU*     3.5     8.1    -      -       -      +
    272A  GLN*     1.3    76.7    -      -       -      +
    274A  SER*     1.3    62.6    +      -       -      +
    276A  LEU*     3.3     3.0    +      -       -      +
    277A  LYS*     3.0    43.2    +      -       +      +
    683C  LEU*     4.0    13.2    -      -       +      -
    684C  THR*     4.1    35.9    -      -       +      +
    687C  HIS*     4.0    23.3    -      -       +      +
    690C  LEU*     3.8    22.8    -      -       +      +
    691C  HIS*     4.7     7.0    -      -       +      -
    694C  LEU*     3.8    17.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 274 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    270A  GLU      3.0    18.1    +      -       -      -
    271A  ASP*     3.2     6.0    +      -       -      -
    273A  ILE*     1.3    77.5    -      -       -      +
    275A  LEU*     1.3    62.4    +      -       -      +
    277A  LYS*     3.5     9.5    +      -       -      +
    278A  GLY*     3.1    19.6    +      -       -      -
    353A  ARG*     4.3     7.6    -      -       -      +
    354A  PRO      4.1    11.1    +      -       -      +
    355A  GLY*     3.4    33.4    +      -       -      -
    356A  VAL*     4.2     8.5    -      -       -      -
    683C  LEU*     3.5    12.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 275 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    264A  PHE*     4.1    17.0    -      -       +      -
    267A  LEU*     3.5    32.8    -      -       +      -
    271A  ASP*     2.8    23.9    +      -       +      +
    272A  GLN      3.9     3.6    -      -       -      +
    274A  SER*     1.3    72.4    -      -       -      +
    276A  LEU*     1.3    57.1    +      -       -      +
    278A  GLY*     3.4     1.9    +      -       -      -
    279A  ALA*     3.0    31.9    +      -       -      +
    348A  LEU*     3.4    26.8    -      -       +      +
    349A  PHE*     4.5     7.4    -      -       +      -
    350A  SER      3.4    27.4    -      -       -      +
    353A  ARG*     4.2     5.6    +      -       +      -
    356A  VAL*     3.9    17.3    -      -       +      -
    362A  VAL*     4.3    13.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 276 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254A  ILE*     4.1    16.2    -      -       +      +
    255A  ILE*     4.1    23.6    -      -       +      -
    258A  ALA*     3.9    19.5    -      -       +      -
    264A  PHE*     3.9    10.5    -      -       +      -
    272A  GLN      3.0    20.4    +      -       -      +
    273A  ILE      3.3     3.3    +      -       -      +
    275A  LEU*     1.3    72.0    -      -       -      +
    277A  LYS*     1.3    59.8    +      -       -      +
    279A  ALA*     4.5     0.4    -      -       +      +
    280A  ALA*     2.9    37.0    +      -       +      +
    348A  LEU*     4.3     9.2    -      -       +      -
    428A  LEU*     4.3     5.4    -      -       +      -
    690C  LEU*     3.8    25.4    -      -       +      -
    694C  LEU*     3.6    31.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 277 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    273A  ILE*     3.0    32.5    +      -       +      +
    274A  SER*     3.8     7.6    -      -       -      +
    276A  LEU*     1.3    76.3    -      -       -      +
    278A  GLY*     1.3    60.6    +      -       -      +
    280A  ALA*     4.1     6.8    +      -       -      +
    281A  PHE      5.4     0.7    +      -       -      -
    354A  PRO      6.1     1.1    -      -       -      -
    404A  ASN*     5.3     1.0    +      -       -      -
    427A  GLU      3.0    22.4    +      -       -      +
    428A  LEU*     3.5    39.7    +      -       -      +
    429A  PHE*     4.7     8.2    -      -       -      -
    430A  GLY*     3.9    13.3    -      -       -      +
    683C  LEU*     5.1     6.1    -      -       +      -
    687C  HIS*     3.2    25.8    +      -       +      +
    690C  LEU*     4.3     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 278 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    274A  SER      3.1    10.6    +      -       -      -
    275A  LEU      3.8     2.9    -      -       -      -
    277A  LYS*     1.3    81.0    -      -       -      +
    279A  ALA*     1.3    56.6    +      -       -      +
    353A  ARG*     3.2    33.6    +      -       -      -
    354A  PRO*     5.9     3.4    -      -       -      -
    404A  ASN*     3.0    25.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 279 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254A  ILE*     5.3     0.4    -      -       -      -
    275A  LEU      3.0    15.8    +      -       -      +
    276A  LEU*     6.3     0.4    -      -       +      -
    278A  GLY*     1.3    76.2    -      -       -      +
    280A  ALA*     1.3    65.1    +      -       -      +
    281A  PHE      3.4     2.7    -      -       -      -
    282A  GLU*     3.1     6.7    +      -       -      +
    283A  LEU*     2.9    33.8    +      -       +      +
    347A  SER*     3.7    16.8    -      -       -      +
    348A  LEU*     4.0    12.6    -      -       +      -
    353A  ARG*     3.5    20.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 280 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  PHE*     3.7    24.9    -      -       +      +
    254A  ILE*     4.4    14.5    -      -       +      +
    255A  ILE*     6.5     0.4    -      -       +      -
    276A  LEU*     2.9    24.3    +      -       +      +
    277A  LYS      4.1     4.7    +      -       -      +
    278A  GLY      3.8     1.0    -      -       -      -
    279A  ALA*     1.3    70.1    -      -       -      +
    281A  PHE*     1.3    61.1    +      -       -      +
    283A  LEU*     4.1     1.2    -      -       -      +
    284A  CYS*     2.9    31.4    +      -       -      -
    428A  LEU*     4.3    21.1    -      -       +      -
    429A  PHE*     5.0     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 281 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  PHE*     3.9    12.1    -      +       -      -
    277A  LYS      5.4     0.6    +      -       -      -
    279A  ALA      3.4     1.0    -      -       -      -
    280A  ALA*     1.3    76.7    -      -       -      +
    282A  GLU*     1.3    60.6    +      -       +      +
    284A  CYS*     3.3     5.4    +      -       +      +
    285A  GLN*     3.0    60.2    +      -       +      +
    323A  MET*     4.0    15.0    -      -       -      -
    400A  LEU*     4.4     4.7    -      -       +      -
    403A  ILE*     4.2     3.1    -      -       +      -
    404A  ASN*     3.3    54.0    -      -       +      +
    407A  HIS*     3.4    41.1    -      +       +      -
    429A  PHE*     4.5    15.7    -      +       +      -
   1433A  D7E      3.5    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 282 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    278A  GLY      4.2     0.4    -      -       -      -
    279A  ALA      3.1     7.0    +      -       -      +
    281A  PHE*     1.3    75.1    -      -       +      +
    283A  LEU*     1.3    65.7    +      -       -      +
    285A  GLN*     3.3     2.1    +      -       -      +
    286A  LEU*     3.0    27.5    +      -       -      +
    347A  SER*     2.8    32.4    +      -       -      +
    353A  ARG*     2.8    35.8    +      -       -      -
    397A  LEU*     4.8     3.8    -      -       -      +
    400A  LEU*     3.7    30.9    -      -       +      +
    401A  ARG*     3.5    24.8    +      -       -      +
    404A  ASN*     3.0    27.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 283 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254A  ILE*     3.6    33.4    -      -       +      -
    257A  PHE*     4.0    22.2    -      -       +      -
    279A  ALA*     2.9    26.7    +      -       +      +
    282A  GLU*     1.3    71.9    -      -       -      +
    284A  CYS*     1.3    62.6    +      -       -      +
    286A  LEU*     3.3     7.6    +      -       +      +
    287A  ARG*     3.1    27.2    +      -       -      +
    344A  GLN*     3.4    48.9    -      -       +      +
    347A  SER*     3.2    28.3    -      -       -      +
    348A  LEU*     4.1     9.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 284 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    247A  SER*     6.0     0.2    -      -       -      -
    250A  MET*     3.6    27.8    -      -       +      +
    251A  PHE*     3.1    33.4    -      -       +      -
    254A  ILE*     3.7    14.4    -      -       -      -
    280A  ALA      2.9    26.5    +      -       -      +
    281A  PHE*     3.4     6.1    -      -       -      +
    283A  LEU*     1.3    76.9    -      -       -      +
    285A  GLN*     1.3    60.5    +      -       -      +
    287A  ARG*     3.3     6.4    +      -       -      +
    288A  PHE*     2.9    41.7    +      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 285 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    281A  PHE*     3.0    48.6    +      -       +      +
    282A  GLU      3.3     4.7    +      -       -      +
    284A  CYS*     1.3    75.0    -      -       -      +
    286A  LEU*     1.3    61.0    +      -       -      +
    288A  PHE*     3.3    16.3    +      -       -      -
    289A  ASN*     2.9    26.0    +      -       -      +
    323A  MET*     3.5    18.2    -      -       +      +
    326A  PHE*     5.2     2.2    -      -       +      -
    327A  HIS*     2.9    36.8    +      -       -      -
    400A  LEU*     4.2     8.3    -      -       +      -
   1433A  D7E      3.3    49.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 286 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  GLU      3.0    23.0    +      -       -      +
    283A  LEU*     3.6     8.1    -      -       -      +
    285A  GLN*     1.3    75.4    -      -       -      +
    287A  ARG*     1.3    63.0    +      -       -      +
    289A  ASN*     3.4    17.0    +      -       -      +
    290A  THR*     3.6    12.5    +      -       -      +
    326A  PHE*     4.4     2.7    -      -       +      -
    330A  LEU*     3.9    15.7    -      -       +      -
    340A  TYR*     3.8    10.4    -      -       +      -
    343A  MET*     3.5    40.2    -      -       +      +
    344A  GLN*     3.9    44.6    -      -       +      +
    347A  SER*     4.6     4.3    -      -       -      -
    397A  LEU*     4.3     8.1    -      -       +      -
    400A  LEU*     4.0    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 287 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158A  GLN*     2.8    27.2    +      -       -      -
    161A  THR*     2.9    45.3    +      -       -      -
    162A  PHE*     3.6    50.4    -      -       +      +
    250A  MET*     3.8    15.9    +      -       +      +
    253A  GLY*     3.4    20.2    +      -       -      -
    254A  ILE*     3.4    25.4    -      -       +      +
    257A  PHE*     3.6    12.1    -      -       -      +
    283A  LEU      3.1    11.2    +      -       -      +
    284A  CYS      3.6     7.4    -      -       -      +
    285A  GLN      3.3     0.2    -      -       -      -
    286A  LEU*     1.3    74.1    -      -       -      +
    288A  PHE*     1.3    63.9    +      -       -      +
    290A  THR*     2.7    25.8    +      -       -      -
    291A  VAL*     3.7     2.4    +      -       -      +
    344A  GLN*     3.5    17.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 288 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    166A  PHE*     4.3    11.0    -      +       -      -
    246A  MET*     4.0    19.1    -      -       +      -
    247A  SER*     6.0     1.8    -      -       -      -
    250A  MET*     3.4    41.7    -      -       +      -
    284A  CYS*     2.9    26.5    +      -       +      +
    285A  GLN*     3.3    23.5    +      -       -      +
    287A  ARG*     1.3    75.4    -      -       -      +
    289A  ASN*     1.3    63.1    +      -       -      +
    291A  VAL*     3.0    29.3    +      -       +      +
    292A  PHE      3.2     8.5    +      -       -      -
    299A  TRP*     3.4    12.6    -      +       +      -
    301A  CYS*     4.3     4.7    -      -       -      -
    327A  HIS*     4.1    10.1    -      -       +      -
   1433A  D7E      3.6    48.0    -      +       +      -
----------------------------------------------------------
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Residues in contact with ASN 289 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285A  GLN      2.9    13.6    +      -       -      +
    286A  LEU      3.5    11.2    -      -       -      +
    287A  ARG      3.2     0.4    -      -       -      -
    288A  PHE*     1.3    78.6    -      -       -      +
    290A  THR*     1.3    59.1    +      -       -      +
    292A  PHE*     3.1    15.3    +      -       -      +
    326A  PHE*     5.5     0.2    -      -       +      -
    327A  HIS*     2.9    48.5    +      -       -      +
    330A  LEU*     3.6    25.7    -      -       +      +
    331A  LYS*     3.3    21.2    +      -       -      +
    340A  TYR*     2.5    33.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with THR 290 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158A  GLN*     5.8     3.4    -      -       -      +
    162A  PHE*     3.4    22.5    -      -       +      -
    164A  THR*     5.7     0.3    -      -       -      +
    286A  LEU      3.6    14.1    -      -       -      +
    287A  ARG*     2.7    18.9    +      -       -      +
    289A  ASN*     1.3    76.0    -      -       -      +
    291A  VAL*     1.3    61.3    +      -       -      +
    331A  LYS*     3.5    14.2    +      -       -      +
    337A  GLU*     4.9    10.5    -      -       -      +
    340A  TYR*     3.7    38.4    -      -       +      -
    344A  GLN*     6.0     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 291 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162A  PHE*     4.5     7.4    -      -       +      -
    164A  THR*     4.3    19.5    -      -       -      +
    166A  PHE*     4.3    10.5    -      -       +      -
    287A  ARG      4.3     1.8    -      -       -      +
    288A  PHE*     3.0    28.5    +      -       +      +
    290A  THR*     1.3    86.7    +      -       -      +
    292A  PHE*     1.3    60.3    +      -       -      +
    293A  ASN      3.7     0.5    +      -       -      -
    299A  TRP*     4.4     3.1    -      -       +      -
    300A  GLU*     2.8    54.0    +      -       -      +
    301A  CYS*     4.1    19.7    -      -       -      -
----------------------------------------------------------
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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