Contacts of the helix formed by residues 40 - 66 (chain A) in PDB entry 1EQ1


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 ASN 40 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  LEU*     5.4     2.4    -      -       -      +
     37A  GLN      6.3     0.7    -      -       -      -
     38A  ASP*     4.6     0.4    -      -       -      +
     39A  PHE*     1.3   115.5    +      -       -      +
     41A  LYS*     1.3    58.5    +      -       -      +
     42A  ALA      3.1     2.0    -      -       -      -
     43A  LEU*     2.5    46.7    +      -       -      +
     44A  LYS*     3.0     5.5    +      -       -      +
     97A  VAL*     3.3    30.5    -      -       +      +
     98A  GLU*     4.2     2.2    -      -       -      -
    101A  ALA*     2.7    41.8    +      -       +      +
    102A  ASN      5.1     0.5    -      -       -      +
    104A  PHE*     5.3     1.7    +      -       -      +
    105A  LYS*     5.7     0.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  ASP*     4.6    19.8    +      -       -      +
     39A  PHE      4.5     0.6    -      -       -      +
     40A  ASN*     1.3    78.5    -      -       -      +
     42A  ALA*     1.3    64.2    +      -       -      +
     44A  LYS*     2.9    18.9    +      -       +      +
     45A  ASP*     3.2    18.4    +      -       -      +
     94A  HIS*     4.9     4.5    -      -       -      +
     95A  PRO*     5.6     0.7    -      -       +      -
     98A  GLU*     3.2    52.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  ASP      5.2     3.0    +      -       -      +
     39A  PHE*     4.2    11.3    +      -       -      +
     40A  ASN      3.1     0.8    -      -       -      -
     41A  LYS*     1.3    80.3    -      -       -      +
     43A  LEU*     1.3    61.3    +      -       -      +
     45A  ASP*     3.2    19.4    +      -       -      +
     46A  GLY*     3.4     9.5    +      -       -      -
    162A  ALA*     5.1    14.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  LEU*     3.7    40.2    -      -       +      -
     39A  PHE      4.0     1.9    +      -       -      +
     40A  ASN*     2.5    29.4    +      -       -      +
     42A  ALA*     1.3    76.0    -      -       -      +
     44A  LYS*     1.3    66.4    +      -       +      +
     46A  GLY*     3.6     0.9    +      -       -      -
     47A  SER*     3.1    31.2    +      -       -      +
     97A  VAL*     3.3    32.5    -      -       +      -
    105A  LYS*     3.2    38.4    -      -       +      -
    159A  LEU*     4.7     7.2    -      -       +      +
    162A  ALA*     5.0     8.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40A  ASN      3.0     3.2    +      -       -      +
     41A  LYS*     2.9    12.4    +      -       +      +
     43A  LEU*     1.3    82.2    -      -       +      +
     45A  ASP*     1.3    59.0    +      -       -      +
     47A  SER*     4.3     3.8    -      -       -      -
     48A  ASP*     2.7    56.0    +      -       -      +
     90A  LEU*     3.3    33.7    +      -       +      +
     93A  ALA*     3.5     3.8    -      -       -      +
     94A  HIS*     3.0    45.4    -      -       -      +
     97A  VAL*     3.2    44.9    -      -       +      -
    104A  PHE*     3.5    19.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  LYS*     3.2    16.1    +      -       -      +
     42A  ALA*     3.2    15.0    +      -       -      +
     44A  LYS*     1.3    80.7    -      -       -      +
     46A  GLY*     1.3    60.2    +      -       -      +
     48A  ASP*     4.2     1.2    -      -       -      +
     49A  SER*     3.2    23.0    +      -       -      -
     94A  HIS*     4.3     9.7    +      -       -      -
    158A  LYS*     5.3     1.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  ALA      3.4     8.6    +      -       -      -
     43A  LEU*     3.6     2.0    +      -       -      -
     44A  LYS      3.3     0.2    -      -       -      -
     45A  ASP*     1.3    77.6    -      -       -      +
     47A  SER*     1.3    65.8    +      -       -      +
     49A  SER*     3.4     2.9    -      -       -      -
     50A  VAL*     3.4    14.4    +      -       -      +
    154A  GLU*     3.8     9.0    -      -       -      +
    155A  VAL*     4.1     2.6    -      -       -      +
    158A  LYS*     3.9    33.0    -      -       -      +
    159A  LEU*     4.6     9.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  PHE*     4.1    13.2    -      -       -      -
     43A  LEU*     3.1    27.2    +      -       -      +
     44A  LYS*     4.0     7.4    -      -       -      -
     46A  GLY*     1.3    73.5    -      -       -      +
     48A  ASP*     1.3    66.0    +      -       -      +
     49A  SER      2.9     4.5    -      -       -      -
     50A  VAL*     2.6    26.2    -      -       -      +
     51A  LEU*     3.0     5.5    -      -       -      +
     90A  LEU*     4.6     4.3    -      -       -      -
    105A  LYS*     5.3     3.3    +      -       -      -
    108A  LEU*     2.9    35.2    -      -       -      +
    155A  VAL*     4.3     1.6    -      -       -      -
    159A  LEU*     4.3     3.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  LYS*     2.7    45.5    +      -       -      +
     45A  ASP*     4.5     1.8    -      -       -      +
     47A  SER*     1.3    71.2    -      -       -      +
     49A  SER*     1.3    60.0    +      -       -      +
     51A  LEU*     3.4    25.0    -      -       +      +
     52A  GLN*     3.7    13.1    +      -       -      +
     90A  LEU*     3.2    11.6    -      -       -      +
     91A  ARG*     3.6    18.1    -      -       +      +
     93A  ALA      3.4     6.2    -      -       -      +
     94A  HIS*     2.4    47.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  ASP      3.2    21.0    +      -       -      -
     46A  GLY*     3.4     9.6    -      -       -      -
     47A  SER      2.8     1.8    +      -       -      -
     48A  ASP*     1.3    75.5    -      -       -      +
     50A  VAL*     1.3    62.7    +      -       -      -
     51A  LEU      2.9     4.8    +      -       -      -
     52A  GLN*     3.1    19.0    +      -       -      +
     53A  GLN*     2.9    28.2    +      -       -      +
    154A  GLU*     3.4    13.5    +      -       -      -
    158A  LYS*     4.5    12.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  GLY      3.4     0.6    +      -       -      -
     47A  SER      2.6    25.1    +      -       -      +
     49A  SER*     1.3    80.4    -      -       -      +
     51A  LEU*     1.3    58.6    +      -       +      +
     53A  GLN*     3.6     2.5    -      -       -      -
     54A  LEU*     2.7    53.4    +      -       +      +
    108A  LEU*     3.0    14.8    -      -       +      -
    112A  VAL*     5.2     3.1    -      -       +      -
    151A  HIS      3.6    23.3    -      -       -      +
    152A  ALA*     5.1     0.7    -      -       -      +
    154A  GLU*     3.0    25.1    +      -       +      +
    155A  VAL*     2.8    33.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  SER      3.0    17.5    -      -       -      +
     48A  ASP*     3.4    13.7    -      -       -      +
     49A  SER      2.9     0.4    -      -       -      -
     50A  VAL*     1.3    89.1    -      -       +      +
     52A  GLN*     1.3    51.4    +      -       -      +
     54A  LEU*     3.6     4.2    -      -       +      +
     55A  SER*     2.4    43.5    +      -       -      -
     87A  ALA*     3.1    24.2    -      -       +      +
     88A  GLU*     3.8     9.2    -      -       -      -
     90A  LEU*     3.3    18.8    -      -       +      -
     91A  ARG*     3.2    44.9    -      -       +      +
    108A  LEU*     3.5    19.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  ASP      3.7    11.6    +      -       -      -
     49A  SER*     3.1    22.1    +      -       -      +
     51A  LEU*     1.3    80.1    -      -       -      +
     53A  GLN*     1.3    72.0    +      -       +      +
     55A  SER*     3.9     5.7    -      -       -      -
     56A  ALA*     3.5    16.5    +      -       -      +
     91A  ARG*     3.4    36.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  SER*     2.9    24.2    +      -       -      +
     50A  VAL*     3.7     4.0    -      -       -      +
     52A  GLN*     1.3    84.1    +      -       +      +
     54A  LEU*     1.3    63.4    +      -       -      +
     56A  ALA*     3.1    12.7    -      -       -      +
    150A  LYS*     5.9     1.1    -      -       -      +
    151A  HIS*     2.9    38.1    +      -       -      +
    154A  GLU*     3.2    37.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  VAL*     2.7    46.3    +      -       +      +
     51A  LEU*     4.0     3.6    -      -       +      +
     53A  GLN*     1.3    71.5    -      -       -      +
     55A  SER*     1.3    61.3    +      -       -      +
     56A  ALA      2.9     8.3    +      -       -      -
     57A  PHE*     2.6    48.3    +      -       +      -
     83A  VAL      4.1     7.2    -      -       -      +
     87A  ALA*     2.9    38.8    -      -       +      -
    112A  VAL*     4.7    16.4    -      -       +      -
    115A  THR*     4.4    11.9    -      -       +      +
    148A  PHE*     6.3     0.7    -      -       +      -
    151A  HIS*     3.3    28.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  LEU      2.4    28.1    +      -       -      -
     52A  GLN*     4.1     7.2    -      -       -      -
     54A  LEU*     1.3    81.2    -      -       -      +
     56A  ALA*     1.3    57.8    +      -       -      +
     58A  SER*     2.3    33.1    +      -       -      -
     59A  SER*     4.1     0.7    +      -       -      -
     84A  GLU*     3.3    40.9    +      -       -      +
     87A  ALA*     3.5    10.6    -      -       -      +
     88A  GLU*     3.8     5.1    +      -       -      +
     91A  ARG*     5.7     2.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  GLN      3.5    11.4    +      -       -      +
     53A  GLN*     3.1    16.5    +      -       -      +
     54A  LEU      2.9     0.6    -      -       -      -
     55A  SER*     1.3    76.4    -      -       -      +
     57A  PHE*     1.3    67.6    +      -       -      +
     58A  SER      3.1     1.8    -      -       -      -
     59A  SER*     2.9    22.8    +      -       -      -
     60A  SER*     3.7     3.3    +      -       -      -
    147A  ASP*     5.8     0.2    -      -       -      +
    151A  HIS*     4.2     7.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  GLN      4.3     0.8    +      -       -      -
     54A  LEU*     2.6    39.7    +      -       +      -
     56A  ALA*     1.3    79.2    -      -       -      +
     58A  SER*     1.3    56.7    +      -       -      +
     60A  SER*     2.4    42.5    +      -       -      -
     61A  LEU*     3.7    11.0    +      -       +      +
     79A  ALA      4.7     1.3    -      -       -      -
     83A  VAL*     3.2    43.7    -      -       +      -
    115A  THR*     3.9     8.5    -      -       +      -
    144A  ALA*     3.4    22.7    -      -       +      -
    147A  ASP*     3.1    33.3    +      -       +      +
    148A  PHE*     3.3    41.7    -      +       -      -
    151A  HIS*     4.3     5.5    +      +       -      -
----------------------------------------------------------
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Residues in contact with SER 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  SER*     2.3    29.4    +      -       -      -
     57A  PHE*     1.3    92.8    -      -       -      +
     59A  SER*     1.3    60.1    +      -       -      +
     60A  SER      3.2     1.0    +      -       -      -
     61A  LEU*     3.5     8.1    +      -       -      +
     80A  ARG*     2.8    56.6    -      -       -      +
     83A  VAL*     3.6    12.3    -      -       -      -
     84A  GLU*     3.2    20.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  SER      5.0     0.9    -      -       -      -
     56A  ALA*     2.9    13.0    +      -       -      -
     58A  SER*     1.3    82.1    +      -       -      +
     60A  SER*     1.3    58.5    +      -       -      +
     61A  LEU      3.3     0.2    -      -       -      -
     62A  GLN*     2.3    75.7    +      -       -      +
     80A  ARG*     3.9     5.2    -      -       -      +
     84A  GLU*     5.4     3.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  ALA      3.8     1.7    +      -       -      -
     57A  PHE*     2.4    43.1    +      -       -      -
     59A  SER*     1.3    73.5    -      -       -      +
     61A  LEU*     1.3    61.8    +      -       -      +
     62A  GLN      3.5     0.2    +      -       -      -
     63A  GLY*     3.6     7.4    +      -       -      -
    140A  LYS*     3.6     9.1    -      -       -      +
    143A  GLN*     3.2    52.8    +      -       -      +
    144A  ALA*     4.5     2.7    -      -       -      -
    147A  ASP*     3.3     9.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  PHE*     4.8    17.0    -      -       +      +
     58A  SER      3.5    10.8    +      -       -      +
     59A  SER      3.3     0.2    -      -       -      -
     60A  SER*     1.3    76.7    -      -       -      +
     62A  GLN*     1.3    55.3    +      -       -      +
     63A  GLY      2.9     2.7    -      -       -      -
     64A  ALA*     2.6    27.9    +      -       -      +
     65A  ILE*     2.7    14.5    -      -       +      +
     76A  LEU*     3.9    24.7    -      -       +      +
     79A  ALA*     4.2    14.4    -      -       +      +
     80A  ARG*     4.4     8.1    -      -       +      +
    122A  LEU*     3.5    26.9    -      -       +      -
    140A  LYS*     3.9    17.7    -      -       +      +
    141A  ILE*     3.5    32.5    -      -       +      -
    144A  ALA*     5.6     4.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  SER*     2.3    50.7    +      -       -      +
     61A  LEU*     1.3    79.1    -      -       -      +
     63A  GLY*     1.3    57.8    +      -       -      +
     65A  ILE*     2.9    12.0    +      -       -      +
     66A  SER*     2.4    43.2    +      -       -      +
     80A  ARG*     3.8    29.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  SER      3.6     7.0    +      -       -      -
     61A  LEU      2.8     1.8    +      -       -      -
     62A  GLN*     1.3    88.1    -      -       -      +
     64A  ALA*     1.3    59.8    +      -       -      +
     66A  SER*     3.7    14.8    +      -       -      -
     67A  ASP*     4.8     0.5    -      -       -      +
    136A  LYS*     3.2    16.3    +      -       -      +
    140A  LYS*     3.5    16.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61A  LEU      2.6    14.7    +      -       -      +
     63A  GLY*     1.3    72.8    -      -       -      -
     65A  ILE*     1.3    51.3    +      -       -      +
     67A  ASP      3.4     1.4    -      -       -      -
     68A  ALA*     2.7    41.8    +      -       -      +
     76A  LEU*     3.3    30.1    -      -       +      -
    136A  LYS*     3.4    10.8    -      -       -      -
    137A  LEU*     3.3    17.3    -      -       +      -
    140A  LYS*     3.3    19.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61A  LEU      2.7    39.3    -      -       -      +
     62A  GLN*     2.9     7.5    +      -       -      +
     64A  ALA*     1.3    73.3    -      -       -      +
     66A  SER*     1.3    59.7    +      -       -      +
     67A  ASP*     2.8    11.8    +      -       -      -
     68A  ALA      3.7     4.0    +      -       -      -
     73A  LYS*     2.8    49.7    -      -       +      +
     76A  LEU*     3.0    37.2    -      -       +      +
     77A  GLU*     3.7    20.0    -      -       +      +
     80A  ARG*     5.3     2.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  GLN*     2.4    33.7    +      -       -      +
     63A  GLY*     3.8    11.0    -      -       -      -
     64A  ALA      3.3     0.4    -      -       -      -
     65A  ILE*     1.3    71.9    -      -       -      +
     67A  ASP*     1.3    74.1    +      -       -      +
----------------------------------------------------------
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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