Contacts of the helix formed by residues 74 - 100 (chain A) in PDB entry 1BAD


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 GLU 74 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  GLU*     5.7     1.5    -      -       -      +
     75A  GLN*     1.3    77.7    +      -       +      +
     76A  ASN*     3.3    20.2    -      -       -      +
     77A  PRO*     3.2    18.7    -      -       -      +
     78A  ILE*     4.3     8.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  GLU*     1.3    90.4    +      -       +      +
     76A  ASN*     1.3    77.7    +      -       -      +
     77A  PRO*     3.2     4.2    -      -       -      +
     78A  ILE*     3.7    15.5    +      -       +      +
     79A  TYR*     3.1    34.7    -      -       +      +
     82A  ARG*     6.1     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  GLU      3.4    22.2    -      -       -      +
     75A  GLN*     1.3    89.7    +      -       -      +
     77A  PRO*     1.4    67.4    -      -       +      +
     78A  ILE      3.0     6.5    +      -       -      -
     79A  TYR*     3.1    31.3    +      -       -      +
     80A  TRP*     4.6     6.4    -      -       +      -
    126A  ALA*     5.4     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  GLU*     3.2    16.8    -      -       -      +
     75A  GLN      3.2     5.2    -      -       -      -
     76A  ASN*     1.4    98.7    -      -       +      +
     78A  ILE*     1.3    67.1    +      -       +      +
     79A  TYR      3.2     0.4    -      -       -      -
     80A  TRP*     2.9    55.8    +      -       +      -
     81A  ALA*     4.3     1.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  GLU*     4.6    10.5    -      -       -      +
     56A  MET*     4.3     7.4    -      -       +      -
     60A  MET*     4.1    49.8    -      -       +      +
     74A  GLU      4.3    16.4    -      -       -      +
     75A  GLN*     4.2    12.8    -      -       -      +
     76A  ASN      3.0     0.6    +      -       -      -
     77A  PRO*     1.3    85.4    -      -       +      +
     79A  TYR*     1.3    67.1    +      -       +      +
     80A  TRP      3.3     0.2    -      -       -      -
     81A  ALA*     3.0     8.6    +      -       +      +
     82A  ARG*     2.9    52.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  GLN*     3.1    43.6    -      -       +      +
     76A  ASN*     3.1    15.5    +      -       -      +
     78A  ILE*     1.3    81.4    -      -       +      +
     80A  TRP*     1.3    62.7    +      -       +      +
     82A  ARG*     3.3    27.0    +      -       -      +
     83A  TYR*     3.0    47.8    -      -       -      +
    126A  ALA*     3.7    25.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  ASN*     4.6     6.7    -      -       +      -
     77A  PRO*     2.9    46.4    +      -       +      -
     79A  TYR*     1.3    77.4    -      -       -      +
     81A  ALA*     1.3    83.8    +      -       +      +
     83A  TYR*     3.4    12.0    +      -       +      +
     84A  ALA*     2.9    30.2    +      -       +      +
    119A  ILE*     5.6     0.3    -      -       -      +
    123A  LEU*     3.9    27.9    -      -       +      +
    126A  ALA*     4.2    26.9    -      -       +      -
    127A  LEU*     3.6    33.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  MET*     3.8    21.4    -      -       +      +
     59A  SER*     5.6     6.3    -      -       -      +
     77A  PRO      4.3     1.6    -      -       -      +
     78A  ILE*     3.0    18.1    +      -       +      +
     80A  TRP*     1.3    91.6    -      -       +      +
     82A  ARG*     1.3    59.5    +      -       -      +
     84A  ALA*     3.5     6.2    +      -       -      +
     85A  ASP*     2.9    30.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      6.3     2.5    -      -       +      -
     56A  MET*     4.0    12.6    -      -       +      -
     60A  MET*     4.0    22.4    -      -       -      +
     78A  ILE*     2.9    37.1    +      -       +      +
     79A  TYR*     3.4    27.2    -      -       -      +
     80A  TRP      3.2     0.2    -      -       -      -
     81A  ALA*     1.3    77.1    -      -       -      +
     83A  TYR*     1.3    63.0    +      -       +      +
     85A  ASP*     3.0     3.5    +      -       -      +
     86A  TRP*     2.8    50.5    +      -       +      +
    189A  TRP*     4.3    21.2    +      -       -      +
    204A  GLU*     4.2    18.6    +      -       -      +
    208A  PHE*     3.5    42.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  TYR*     3.0    50.6    +      -       +      +
     80A  TRP*     3.7     9.6    -      -       -      +
     82A  ARG*     1.3    79.5    -      -       +      +
     84A  ALA*     1.3    62.0    +      -       -      +
     86A  TRP*     3.6    44.3    +      +       +      +
     87A  LEU*     3.5    14.2    +      -       -      +
    115A  ASP      5.4     0.3    -      -       -      +
    118A  MET*     4.8     2.4    -      -       -      +
    119A  ILE*     3.6    34.6    -      -       +      +
    122A  GLY*     3.4    44.0    -      -       -      -
    123A  LEU*     3.9     1.1    -      -       -      +
    126A  ALA*     4.2     1.8    -      -       +      -
    189A  TRP*     3.8    28.5    +      +       -      -
----------------------------------------------------------
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Residues in contact with ALA 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  TRP*     2.9    18.2    +      -       +      +
     81A  ALA*     3.7     7.4    -      -       -      +
     83A  TYR*     1.3    75.6    -      -       -      +
     85A  ASP*     1.3    64.9    +      -       -      +
     87A  LEU*     3.0    12.8    +      -       -      +
     88A  PHE*     3.0    37.6    +      -       +      -
    119A  ILE*     3.9    15.2    -      -       +      +
    123A  LEU*     6.6     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      3.3    34.0    -      -       -      +
     52A  ILE*     3.2    32.6    -      -       -      +
     53A  ALA*     4.6     1.0    -      -       -      -
     56A  MET*     3.4    25.7    -      -       -      +
     81A  ALA      2.9    19.4    +      -       -      +
     82A  ARG*     3.0     7.2    +      -       -      +
     84A  ALA*     1.3    73.3    -      -       -      +
     86A  TRP*     1.3    67.9    +      -       -      +
     88A  PHE*     3.0    10.6    +      -       -      +
     89A  THR*     2.8    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 86 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      3.5    55.0    -      -       +      +
     82A  ARG*     2.8    46.5    +      -       +      +
     83A  TYR*     3.6    29.6    -      +       -      +
     84A  ALA      3.2     0.2    -      -       -      -
     85A  ASP*     1.3    82.7    -      -       -      +
     87A  LEU*     1.3    62.9    +      -       -      +
     89A  THR*     4.0     5.8    -      -       -      -
     90A  THR*     2.7    33.8    +      -       -      +
    115A  ASP*     3.6    12.1    -      -       -      +
    118A  MET*     4.4    34.3    -      -       +      -
    189A  TRP*     3.7    54.1    -      +       +      -
    208A  PHE*     6.1     2.6    -      +       -      -
----------------------------------------------------------
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Residues in contact with LEU 87 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83A  TYR      3.5     8.8    +      -       -      +
     84A  ALA      3.0    10.1    +      -       -      +
     86A  TRP*     1.3    79.9    -      -       -      +
     88A  PHE*     1.3    77.4    +      -       +      +
     91A  PRO*     3.2    25.2    -      -       +      +
    112A  VAL*     4.6    20.9    -      -       +      +
    115A  ASP*     3.7    33.1    -      -       +      +
    116A  GLY*     4.8     2.5    -      -       -      +
    119A  ILE*     4.0    23.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 88 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ILE*     3.7    37.6    -      -       +      +
     84A  ALA*     3.0    41.5    -      -       +      -
     85A  ASP*     3.0     7.8    +      -       -      +
     87A  LEU*     1.3   102.8    -      -       +      +
     89A  THR*     1.3    60.5    +      -       -      +
     91A  PRO*     3.4     7.7    -      -       -      +
     92A  LEU*     3.7    12.5    -      -       -      +
    119A  ILE*     5.7     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 89 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      3.8    36.7    -      -       +      +
     49A  VAL*     5.3     1.4    -      -       -      +
     52A  ILE*     3.9    19.7    -      -       -      +
     53A  ALA*     5.3     1.2    -      -       -      +
     85A  ASP*     2.8    33.5    +      -       -      +
     86A  TRP*     3.7     7.2    -      -       -      +
     88A  PHE*     1.3    77.0    -      -       -      +
     90A  THR*     1.3    79.9    +      -       -      +
     91A  PRO*     3.3     1.2    -      -       -      -
     92A  LEU*     3.9     4.6    +      -       -      +
     93A  LEU*     3.2    23.2    -      -       -      +
    216A  LYS*     4.0     7.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 90 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      3.6    38.1    -      -       +      +
     86A  TRP*     2.7    23.3    +      -       -      -
     89A  THR*     1.3    87.5    -      -       -      +
     91A  PRO*     1.4    65.8    -      -       +      +
     92A  LEU      3.1     5.6    +      -       -      -
     93A  LEU*     3.1    15.2    +      -       -      +
     94A  LEU*     3.1    23.4    +      -       +      +
    111A  LEU*     5.2     6.1    -      -       +      -
    115A  ASP*     3.5    26.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  LEU*     3.2    24.7    -      -       +      +
     88A  PHE*     3.4     5.8    -      -       -      +
     89A  THR      3.3     5.2    -      -       -      -
     90A  THR*     1.4    94.7    -      -       +      +
     92A  LEU*     1.3    71.8    +      -       +      +
     93A  LEU      3.4     0.2    -      -       -      -
     94A  LEU*     3.7     9.5    -      -       +      +
     95A  LEU*     2.8    31.4    +      -       -      +
    108A  ILE*     5.1     8.9    -      -       +      +
    111A  LEU*     5.7     4.0    -      -       +      -
    112A  VAL*     4.2    25.8    -      -       +      -
    115A  ASP*     5.3     2.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  ILE*     3.4    23.2    -      -       +      +
     48A  LEU*     3.8    36.3    -      -       +      -
     49A  VAL*     3.8    31.6    -      -       +      +
     52A  ILE*     4.7    10.8    -      -       +      -
     88A  PHE      3.7    17.3    -      -       -      +
     89A  THR      4.4     4.7    -      -       -      +
     90A  THR      3.1     0.8    -      -       -      -
     91A  PRO*     1.3    88.0    -      -       +      +
     93A  LEU*     1.3    61.3    +      -       -      +
     95A  LEU*     3.4     5.2    +      -       +      +
     96A  ASP*     2.9    29.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  VAL*     3.6    28.9    -      -       +      -
     89A  THR*     3.2    31.0    -      -       -      +
     90A  THR      3.1     7.0    +      -       -      +
     92A  LEU*     1.3    78.6    -      -       -      +
     94A  LEU*     1.3    60.6    +      -       +      +
     96A  ASP*     3.5     7.4    +      -       -      +
     97A  LEU*     2.9    28.1    +      -       -      +
    215A  ALA*     4.8     3.8    -      -       +      +
    216A  LYS*     3.9    38.8    -      -       +      +
    219A  PHE*     3.8    35.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216   RET      4.6     9.6    -      -       +      -
     90A  THR*     3.1    31.1    +      -       +      +
     91A  PRO*     3.9     9.9    -      -       +      +
     93A  LEU*     1.3    78.9    -      -       +      +
     95A  LEU*     1.3    59.5    +      -       -      +
     97A  LEU*     3.3     4.7    +      -       +      +
     98A  ALA*     2.8    32.1    +      -       +      +
    107A  THR*     6.0     2.2    -      -       +      -
    108A  ILE*     5.0     6.7    -      -       +      -
    111A  LEU*     4.9    15.7    -      -       +      -
    148A  ILE*     5.3     4.5    -      -       +      -
    152A  LEU*     4.1    24.2    -      -       +      -
    182A  TRP*     3.5    44.9    -      -       +      -
    219A  PHE*     5.5     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  ILE*     4.1    24.9    -      -       +      -
     91A  PRO      2.8    20.2    +      -       -      +
     92A  LEU*     3.8     5.2    -      -       +      +
     93A  LEU      3.3     0.2    -      -       -      -
     94A  LEU*     1.3    74.9    -      -       -      +
     96A  ASP*     1.3    59.9    +      -       -      +
     98A  ALA*     3.6     6.2    -      -       +      +
     99A  LEU*     2.8    41.4    +      -       +      +
    108A  ILE*     4.1    29.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  PHE*     3.7    17.4    -      -       -      +
     45A  ILE*     4.2    15.2    -      -       +      +
     46A  THR*     5.1     1.5    -      -       -      -
     92A  LEU      2.9    18.4    +      -       -      +
     93A  LEU*     3.6     9.1    -      -       -      +
     95A  LEU*     1.3    77.5    -      -       -      +
     97A  LEU*     1.3    60.4    +      -       -      +
     99A  LEU*     3.3     6.5    +      -       -      +
    100A  LEU*     2.8    36.2    +      -       -      +
    219A  PHE*     4.7    13.5    -      -       -      +
    223A  LEU*     3.2    43.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     93A  LEU      2.9    18.0    +      -       -      +
     94A  LEU*     3.6     5.8    -      -       +      +
     96A  ASP*     1.3    81.1    +      -       -      +
     98A  ALA*     1.3    63.5    -      -       -      +
    100A  LEU*     3.1    27.5    +      -       +      -
    152A  LEU*     4.0    16.6    -      -       +      -
    170A  THR*     6.6     0.2    -      -       +      -
    171A  PHE*     5.6     7.7    -      -       +      -
    174A  LEU*     3.6    31.9    -      -       +      -
    178A  THR*     4.5     7.6    -      -       +      -
    182A  TRP*     3.8    34.3    -      -       +      -
    219A  PHE*     4.0    18.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94A  LEU*     2.8    20.6    +      -       +      +
     95A  LEU*     3.2    10.3    +      -       +      +
     97A  LEU*     1.3    79.1    -      -       -      +
     99A  LEU*     1.3    62.7    +      -       -      +
    100A  LEU      4.5     1.9    -      -       -      -
    107A  THR*     4.8    19.1    -      -       +      -
    108A  ILE*     5.0     5.8    -      -       +      -
    152A  LEU*     6.0     5.8    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
     41A  LYS*     3.8    45.3    -      -       +      +
     42A  PHE*     3.6    31.6    -      -       +      -
     45A  ILE*     6.0     4.3    -      -       +      -
     95A  LEU*     2.8    25.6    +      -       +      +
     96A  ASP*     3.8     5.2    -      -       -      +
     98A  ALA*     1.3    78.0    -      -       -      +
    100A  LEU*     1.3    62.4    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     42A  PHE*     3.9    16.4    -      -       +      -
     96A  ASP*     2.8    25.4    +      -       -      +
     97A  LEU*     3.1    22.6    +      -       +      +
     98A  ALA      4.5     2.5    -      -       -      -
     99A  LEU*     1.3    83.2    -      -       -      +
    166A  GLU*     5.8     4.0    -      -       -      +
    167A  VAL*     5.3    11.1    -      -       +      +
    170A  THR*     4.1    26.7    -      -       +      -
    171A  PHE*     3.5    31.4    -      -       +      -
    174A  LEU*     5.7     1.1    -      -       +      -
    219A  PHE      5.4     0.2    -      -       -      +
    222A  ILE*     4.6    10.5    -      -       +      +
    223A  LEU*     4.2    39.5    -      -       +      +
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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