Contacts of the helix formed by residues 90 - 115 (chain A) in PDB entry 2L6X


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 90 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  MET*     4.2    18.6    -      -       +      +
     82A  VAL*     6.0     2.7    -      -       +      -
     89A  SER*     1.3    93.2    +      -       -      +
     91A  THR*     1.3    65.3    +      -       -      +
     92A  VAL*     3.1    18.3    +      -       +      +
     93A  PHE*     3.2    20.8    +      -       +      +
     94A  ARG*     4.1     2.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83A  TRP*     3.4    33.7    -      -       +      -
     89A  SER*     3.0     3.5    +      -       -      +
     90A  PRO*     1.3    67.0    -      -       -      +
     92A  VAL*     1.3    61.4    +      -       -      +
     93A  PHE      2.9     3.7    +      -       -      -
     94A  ARG*     3.0    14.5    +      -       -      +
     95A  TYR*     2.7    38.3    +      -       -      +
    137A  PHE*     6.4     2.7    -      -       -      -
    141A  GLY      5.9     3.8    -      -       -      +
    142A  GLU*     6.1     2.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90A  PRO*     3.9    20.0    -      -       +      -
     91A  THR*     1.3    83.1    +      -       -      +
     93A  PHE*     1.3    70.2    +      -       +      +
     95A  TYR*     4.3    11.7    -      -       +      -
     96A  ILE*     3.0    46.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  HIS*     3.4    23.3    +      +       -      +
     79A  MET*     3.4    40.4    -      -       +      -
     90A  PRO*     3.2    11.9    +      -       +      +
     91A  THR      3.0     0.6    -      -       -      -
     92A  VAL*     1.3    92.9    -      -       +      +
     94A  ARG*     1.3    56.3    +      -       -      +
     96A  ILE*     4.0     5.6    -      -       +      +
     97A  ASP*     2.7    38.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  HIS*     4.1     2.6    -      -       -      -
     76A  TYR*     3.4    52.6    +      -       +      +
     79A  MET*     3.9    19.6    +      -       +      +
     80A  ARG*     3.1    44.4    -      -       -      +
     83A  TRP*     3.4    52.5    -      -       -      +
     89A  SER*     4.9     1.6    +      -       -      -
     90A  PRO      4.1     1.3    +      -       -      +
     91A  THR*     3.0    17.8    +      -       -      +
     93A  PHE*     1.3    79.9    -      -       -      +
     95A  TYR*     1.3    57.2    +      -       -      +
     97A  ASP*     3.9     4.8    -      -       -      +
     98A  TRP*     2.9    33.4    +      -       -      +
    137A  PHE*     5.1    18.3    -      -       +      -
    223A  TYR*     5.9     0.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  THR*     2.7    24.0    +      -       -      +
     92A  VAL*     3.8    10.3    -      -       +      -
     94A  ARG*     1.3    71.6    -      -       -      +
     96A  ILE*     1.3    87.6    +      -       +      +
     98A  TRP*     3.8     7.0    -      -       -      +
     99A  LEU*     2.8    54.3    +      -       +      +
    134A  MET*     3.4    43.6    -      -       +      +
    137A  PHE*     5.6    10.7    -      +       +      -
    138A  GLY*     5.8     6.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92A  VAL*     3.0    29.3    +      -       +      +
     93A  PHE*     4.1     5.8    -      -       +      +
     95A  TYR*     1.3    93.7    -      -       +      +
     97A  ASP*     1.3    57.4    +      -       -      +
     99A  LEU*     3.5     7.6    -      -       +      +
    100A  LEU*     2.7    52.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  ILE*     4.5     2.1    -      -       -      +
     72A  ALA*     3.8     7.6    -      -       -      +
     75A  HIS*     3.1    42.9    +      -       +      +
     76A  TYR*     3.5    26.5    -      -       -      +
     93A  PHE      2.7    24.1    +      -       -      +
     94A  ARG      3.9     1.5    -      -       -      +
     96A  ILE*     1.3    72.9    -      -       -      +
     98A  TRP*     1.3    53.7    +      -       -      +
    100A  LEU*     3.1     6.4    +      -       -      +
    101A  THR*     2.6    60.7    +      -       -      +
    231A  LYS*     4.8     0.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  TYR*     4.5    15.3    -      +       +      -
     94A  ARG      2.9    22.4    +      -       -      +
     95A  TYR*     3.8     4.3    -      -       -      +
     97A  ASP*     1.3    80.8    +      -       -      +
     99A  LEU*     1.3    56.3    +      -       -      +
    101A  THR*     3.3     8.1    -      -       -      -
    102A  VAL*     2.8    60.9    +      -       +      +
    105A  LEU*     6.2     0.2    -      -       +      -
    130A  GLY      6.0     0.2    -      -       -      -
    133A  VAL*     3.9    18.4    -      -       +      -
    134A  MET*     4.2    21.3    -      -       +      -
    137A  PHE*     3.6    42.8    -      +       +      -
    197A  TRP*     6.2     1.3    -      +       -      -
    301A  RET      3.1    80.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  TYR*     2.8    54.2    +      -       +      +
     96A  ILE*     3.5     5.4    -      -       +      +
     98A  TRP*     1.3    76.7    -      -       -      +
    100A  LEU*     1.3    57.7    +      -       -      +
    101A  THR      3.5     0.2    -      -       -      -
    102A  VAL*     4.7     4.0    -      -       +      -
    103A  PRO*     2.9    30.8    -      -       +      +
    130A  GLY      5.8     0.9    -      -       -      +
    131A  SER*     4.9    14.8    -      -       -      +
    134A  MET*     4.3    24.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 100 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  ILE*     6.5     0.7    -      -       +      -
     96A  ILE*     2.7    30.6    +      -       +      +
     97A  ASP*     3.7     5.4    -      -       -      +
     99A  LEU*     1.3    79.9    -      -       -      +
    101A  THR*     1.3    67.0    +      -       +      +
    102A  VAL      3.6     0.2    -      -       -      -
    103A  PRO*     3.9     5.0    -      -       -      +
    104A  LEU*     2.9    53.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 101 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  VAL*     4.2     9.0    -      -       +      +
     71A  ILE*     5.8     3.4    -      -       +      -
     72A  ALA*     3.2    37.7    -      -       +      +
     97A  ASP*     2.6    37.6    +      -       -      +
     98A  TRP*     3.2    15.6    +      -       -      -
    100A  LEU*     1.3    90.8    -      -       +      +
    102A  VAL*     1.3    58.4    +      -       -      +
    103A  PRO      3.5     0.4    -      -       -      -
    104A  LEU*     3.7     5.2    -      -       +      -
    105A  LEU*     2.7    43.8    +      -       -      +
    231A  LYS*     4.7     3.5    -      -       -      -
    301A  RET      5.1     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 102 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98A  TRP*     2.8    53.9    +      -       +      +
     99A  LEU*     4.7     5.2    -      -       +      -
    101A  THR*     1.3    77.2    +      -       -      +
    103A  PRO*     1.3    69.1    -      -       +      +
    105A  LEU*     3.3     9.3    -      -       +      +
    106A  ILE*     2.9    42.4    +      -       +      +
    126A  LYS*     4.9     8.3    -      -       +      +
    127A  LEU*     6.3     0.2    -      -       -      -
    130A  GLY*     4.7    21.1    -      -       -      +
    197A  TRP*     6.4     2.2    -      -       +      -
    301A  RET      5.4     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 103 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  LEU*     2.9    33.4    -      -       +      +
    100A  LEU*     4.2     5.8    -      -       -      +
    101A  THR      3.6     0.4    -      -       -      -
    102A  VAL*     1.3   103.7    -      -       +      +
    104A  LEU*     1.3    60.0    +      -       +      +
    106A  ILE*     4.5     4.5    -      -       +      -
    107A  CYS*     2.8    33.8    +      -       -      +
    123A  LEU*     4.2     9.7    -      -       +      +
    126A  LYS*     6.5     0.2    -      -       +      -
    127A  LEU*     5.6    12.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 104 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  VAL*     3.6    20.2    -      -       +      -
    100A  LEU*     2.9    45.5    -      -       +      +
    101A  THR*     3.8     0.7    -      -       +      +
    102A  VAL      3.2     0.4    -      -       -      -
    103A  PRO*     1.3    80.7    -      -       +      +
    105A  LEU*     1.3    60.7    +      -       -      +
    107A  CYS*     6.0     0.2    -      -       +      -
    108A  GLU*     2.6    61.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 105 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  SER*     4.9     0.7    +      -       -      -
     68A  VAL*     3.3    29.3    -      -       +      +
     69A  THR*     4.6    10.1    -      -       -      +
     72A  ALA*     5.9     0.4    -      -       +      -
    101A  THR*     2.7    40.2    +      -       -      +
    102A  VAL*     3.3    12.1    -      -       +      +
    104A  LEU*     1.3    74.3    -      -       -      +
    106A  ILE*     1.3    82.1    +      -       +      +
    108A  GLU*     4.1     0.4    -      -       -      +
    109A  PHE*     3.0    32.6    +      -       +      +
    193A  ILE*     6.3     1.8    -      -       +      -
    230A  ASN      5.9     2.2    -      -       -      +
    231A  LYS*     5.8     4.7    -      -       +      -
    234A  PHE*     4.3    25.8    -      -       +      -
    301A  RET      5.3    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 106 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  VAL*     2.9    28.3    +      -       +      +
    103A  PRO*     4.3     3.1    -      -       +      +
    105A  LEU*     1.3    96.1    -      -       +      +
    107A  CYS*     1.3    68.9    +      -       -      +
    109A  PHE*     3.2     6.5    +      -       +      +
    110A  TYR*     2.8    45.8    +      -       +      -
    123A  LEU*     4.7     8.7    -      -       +      -
    126A  LYS*     3.3    57.7    -      -       +      -
    189A  MET*     6.4     1.3    -      -       -      -
    193A  ILE*     5.8     7.9    -      -       +      -
    197A  TRP*     6.4     2.0    -      -       +      -
    234A  PHE*     6.0     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 107 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  PRO      2.8    23.3    +      -       -      +
    104A  LEU      4.1     0.2    -      -       -      +
    106A  ILE*     1.3    77.4    -      -       -      +
    108A  GLU*     1.3    65.7    +      -       -      +
    110A  TYR*     3.6     4.0    -      -       -      +
    111A  LEU*     2.7    44.8    +      -       -      +
    123A  LEU*     3.4    38.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 108 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  VAL*     3.6    43.5    -      -       +      +
     65A  SER      4.8     0.4    -      -       -      +
     68A  VAL*     5.3     2.0    -      -       +      -
    104A  LEU*     2.6    54.9    +      -       +      +
    105A  LEU*     4.1     2.5    -      -       -      +
    107A  CYS*     1.3    88.1    -      -       -      +
    109A  PHE*     1.3    67.7    +      -       -      +
    111A  LEU*     2.9    27.6    +      -       +      +
    112A  ILE*     3.0    18.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 109 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58A  TRP*     4.5    11.0    -      +       -      -
     61A  SER*     4.5     9.0    +      -       -      -
     64A  VAL*     4.7     2.0    -      -       -      +
     65A  SER*     4.4    23.5    +      -       -      +
    105A  LEU      3.0    22.6    +      -       -      +
    106A  ILE*     3.6     6.1    -      -       +      +
    108A  GLU*     1.3    74.9    -      -       -      +
    110A  TYR*     1.3    80.1    +      +       -      +
    112A  ILE*     4.3     1.6    -      -       -      +
    113A  LEU*     3.0    56.4    +      -       +      +
    185A  ALA*     4.6     6.1    -      -       +      -
    186A  TYR*     5.7     2.0    -      +       -      -
    189A  MET*     3.8    29.8    -      -       +      -
    234A  PHE*     4.6     7.9    -      +       +      -
    238A  ILE*     3.5    40.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 110 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  ILE*     2.8    40.7    +      -       +      +
    107A  CYS*     3.9     4.3    -      -       -      +
    109A  PHE*     1.3    88.0    -      +       -      +
    111A  LEU*     1.3    56.5    +      -       -      +
    113A  LEU*     4.0    18.6    -      -       +      -
    114A  ALA*     2.7    39.0    +      -       -      +
    120A  ALA*     3.6    22.9    -      -       +      +
    122A  SER*     2.9    37.0    -      -       -      -
    123A  LEU*     5.2     2.2    -      -       +      +
    126A  LYS*     3.6    26.9    +      -       +      -
    166A  LEU*     3.5    26.5    -      -       +      +
    186A  TYR*     4.5    13.5    -      +       -      -
    189A  MET*     5.7     3.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 111 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  VAL*     5.7     2.9    -      -       +      -
    107A  CYS*     2.7    29.8    +      -       -      +
    108A  GLU*     2.9    23.2    +      -       +      +
    110A  TYR*     1.3    73.9    -      -       -      +
    112A  ILE*     1.3    68.3    +      -       +      +
    114A  ALA*     3.6     1.7    -      -       -      +
    115A  ALA*     2.7    35.0    +      -       +      +
    118A  ASN      4.8     1.6    -      -       -      +
    119A  VAL*     4.7    19.0    -      -       +      +
    120A  ALA      5.4     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 112 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  LYS*     4.3    11.3    -      -       -      +
     60A  THR*     3.8    27.1    -      -       +      +
     61A  SER*     3.2    39.3    -      -       -      +
     64A  VAL*     3.6    33.2    -      -       +      -
    108A  GLU      3.0     5.8    +      -       -      +
    109A  PHE      4.4     0.2    -      -       -      +
    111A  LEU*     1.3    91.5    -      -       +      +
    113A  LEU*     1.3    63.7    +      -       -      +
    115A  ALA*     3.1    22.2    +      -       +      +
    116A  ALA*     4.1     1.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 113 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58A  TRP*     5.3    12.6    -      -       +      -
     61A  SER*     4.2     4.6    +      -       -      +
    109A  PHE*     3.0    54.1    +      -       +      +
    110A  TYR*     3.8    17.3    -      -       +      +
    112A  ILE*     1.3    80.1    -      -       -      +
    114A  ALA*     1.3    61.9    +      -       +      +
    115A  ALA      3.1     0.4    +      -       -      -
    116A  ALA*     3.6    15.1    +      -       -      +
    182A  VAL*     3.2    45.9    -      -       +      +
    185A  ALA*     5.4     2.0    -      -       +      -
    186A  TYR*     4.9    16.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 114 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  TYR      2.7    17.7    +      -       -      +
    111A  LEU      4.1     0.2    -      -       -      +
    113A  LEU*     1.3    71.8    -      -       +      +
    115A  ALA*     1.3    49.6    +      -       -      +
    116A  ALA      2.9     5.8    -      -       -      -
    117A  THR*     2.8    21.7    +      -       +      +
    118A  ASN      2.7    32.1    +      -       -      -
    119A  VAL*     3.2     8.5    -      -       -      +
    120A  ALA*     3.0    41.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 115 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  LYS*     5.6     3.2    -      -       -      -
    111A  LEU*     2.7    16.4    +      -       +      +
    112A  ILE*     3.1    26.9    -      -       +      +
    113A  LEU      3.1     0.4    -      -       -      -
    114A  ALA*     1.3    78.1    -      -       -      +
    116A  ALA*     1.3    61.4    +      -       -      +
    117A  THR      3.1     2.1    +      -       -      -
    118A  ASN*     3.8    15.0    +      -       -      -
----------------------------------------------------------
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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