Contacts of the helix formed by residues 80 - 104 (chain A) in PDB entry 1ALU


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 80 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  PHE*     3.9    16.9    -      -       +      -
     79A  ASN*     1.3    72.2    +      -       -      +
     81A  GLU*     1.3    59.8    +      -       -      +
     83A  CYS*     3.3     1.4    +      -       -      +
     84A  LEU*     2.9    37.0    +      -       +      +
    129A  LYS*     4.6     8.3    +      -       -      -
    184A  MET*     3.8    52.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  ASN*     3.3     8.4    +      -       -      +
     80A  GLU*     1.3    79.8    -      -       +      +
     82A  THR*     1.3    66.7    +      -       +      +
     84A  LEU*     3.6     0.4    +      -       -      -
     85A  VAL*     3.2    28.0    +      -       -      +
    133A  LEU*     3.6    27.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70A  LYS      4.6     4.3    +      -       -      +
     71A  ASP*     2.9    25.3    +      -       -      +
     72A  GLY*     3.8     0.5    -      -       -      -
     79A  ASN*     3.1    35.7    +      -       -      +
     81A  GLU*     1.3    74.0    -      -       +      +
     83A  CYS*     1.3    61.8    +      -       -      +
     85A  VAL*     3.4     7.7    +      -       -      +
     86A  LYS*     2.9    28.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  ASP      3.4     3.6    -      -       -      -
     72A  GLY      3.4    11.4    -      -       -      +
     73A  CYS*     2.0    51.4    -      -       -      -
     78A  PHE*     4.9     0.7    -      -       +      -
     79A  ASN      3.0    19.8    +      -       -      +
     80A  GLU*     3.7     3.8    -      -       -      +
     82A  THR*     1.3    78.4    +      -       -      +
     84A  LEU*     1.3    55.3    +      -       -      +
     86A  LYS*     3.0     4.2    +      -       -      +
     87A  ILE*     2.8    36.8    +      -       -      +
    180A  ALA*     3.5    19.1    -      -       -      -
    184A  MET*     3.5    13.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  GLU*     2.9    24.4    +      -       +      +
     81A  GLU*     4.0     3.8    -      -       -      +
     83A  CYS*     1.3    75.3    -      -       -      +
     85A  VAL*     1.3    61.7    +      -       -      +
     87A  ILE*     3.3     8.0    +      -       +      +
     88A  ILE*     3.1    38.2    +      -       +      +
    126A  LEU*     3.9    28.9    -      -       +      +
    129A  LYS*     4.1    22.0    -      -       +      +
    130A  ALA*     3.7    38.1    -      -       +      +
    133A  LEU*     4.3     7.4    -      -       +      -
    181A  LEU*     4.4    13.7    -      -       +      -
    184A  MET*     4.6     7.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81A  GLU      3.2    15.9    +      -       -      +
     82A  THR*     3.6    10.3    -      -       -      +
     83A  CYS      3.2     0.2    -      -       -      -
     84A  LEU*     1.3    71.7    -      -       -      +
     86A  LYS*     1.3    61.9    +      -       -      +
     88A  ILE*     3.4     5.9    +      -       -      +
     89A  THR*     2.8    44.2    +      -       -      +
    130A  ALA*     6.0     0.2    -      -       +      -
    133A  LEU*     3.6    24.9    -      -       +      -
    134A  ASP*     5.9     1.6    -      -       +      +
    136A  ILE*     4.7    17.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 86 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  PRO*     5.3     2.7    -      -       -      +
     66A  LYS      3.2    29.6    +      -       -      +
     67A  MET*     3.8    13.9    -      -       +      -
     71A  ASP*     3.5    43.8    +      -       +      +
     73A  CYS*     4.6     0.7    -      -       -      -
     82A  THR      2.9    14.8    +      -       -      +
     83A  CYS*     3.0     8.9    +      -       -      +
     85A  VAL*     1.3    79.2    -      -       -      +
     87A  ILE*     1.3    59.2    +      -       -      +
     89A  THR*     4.3     8.7    -      -       +      -
     90A  GLY*     2.8    34.5    +      -       -      +
     93A  GLU*     5.5     3.8    +      -       -      -
    173A  PHE*     3.7    16.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 87 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ILE*     6.2     0.7    -      -       +      -
     67A  MET*     3.7    11.9    -      -       +      -
     83A  CYS*     2.8    36.1    +      -       -      +
     84A  LEU*     3.7    11.2    -      -       +      +
     85A  VAL      3.3     0.2    -      -       -      -
     86A  LYS*     1.3    76.9    -      -       -      +
     88A  ILE*     1.3    62.0    +      -       -      +
     90A  GLY      3.4     0.2    +      -       -      -
     91A  LEU*     2.9    37.1    +      -       +      +
    126A  LEU*     3.9    25.6    -      -       +      -
    173A  PHE*     3.6     8.3    -      -       -      -
    177A  SER*     3.6    37.9    -      -       -      +
    180A  ALA*     4.7     0.2    -      -       +      -
    181A  LEU*     4.0    31.4    -      -       +      -
    184A  MET*     4.5     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 88 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84A  LEU*     3.1    22.1    +      -       +      +
     85A  VAL*     3.9     3.1    -      -       -      +
     87A  ILE*     1.3    75.5    -      -       -      +
     89A  THR*     1.3    56.8    +      -       -      +
     91A  LEU*     3.2     7.6    +      -       -      +
     92A  LEU*     2.8    45.9    +      -       +      +
    123A  ILE*     4.5     8.5    -      -       +      -
    126A  LEU*     3.8    47.1    -      -       +      +
    127A  GLN*     4.2    16.4    -      -       +      +
    130A  ALA*     4.0    19.1    -      -       +      -
    136A  ILE*     3.9    27.6    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
     85A  VAL*     2.8    31.2    +      -       -      +
     86A  LYS*     3.7    11.2    -      -       +      -
     88A  ILE*     1.3    76.9    -      -       -      +
     90A  GLY*     1.4    57.3    +      -       -      +
     92A  LEU*     3.2     5.1    +      -       -      +
     93A  GLU*     2.9    54.2    +      -       +      +
    136A  ILE*     3.1    23.9    -      -       -      +
    137A  THR*     4.7    13.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 90 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  PRO*     3.7     7.8    -      -       -      +
     86A  LYS*     2.8    22.7    +      -       -      +
     87A  ILE      3.8     0.2    -      -       -      -
     89A  THR*     1.4    70.3    -      -       -      +
     91A  LEU*     1.3    64.7    +      -       -      +
     93A  GLU*     3.1    16.3    +      -       -      +
     94A  PHE*     2.9    27.8    +      -       -      -
    173A  PHE*     3.7    19.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  ILE*     2.9    27.7    +      -       +      +
     88A  ILE*     3.7     1.8    -      -       -      +
     90A  GLY*     1.3    76.2    -      -       -      +
     92A  LEU*     1.4    65.4    +      -       -      +
     94A  PHE*     3.1    15.6    +      -       -      +
     95A  GLU*     3.4    14.6    +      -       -      +
    119A  THR*     4.5     6.7    -      -       +      +
    122A  LEU*     3.6    21.5    -      -       +      -
    123A  ILE*     3.6    24.8    -      -       +      +
    126A  LEU*     3.6    31.0    -      -       +      -
    170A  PHE*     3.8    19.7    -      -       +      -
    173A  PHE*     4.1    12.3    -      -       +      -
    174A  LEU*     3.8    26.0    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
     88A  ILE*     2.8    28.0    +      -       +      +
     89A  THR*     3.2     5.6    +      -       -      +
     91A  LEU*     1.4    78.4    -      -       -      +
     93A  GLU*     1.3    60.6    +      -       -      +
     95A  GLU*     3.3    36.7    +      -       -      +
     96A  VAL      4.8     0.7    +      -       -      -
    123A  ILE*     4.0    22.7    -      -       +      -
    127A  GLN*     4.8     5.6    -      -       -      +
    136A  ILE*     3.8    27.4    -      -       +      -
    137A  THR      4.1     2.9    -      -       -      +
    138A  THR*     3.9    27.4    -      -       +      -
    139A  PRO*     3.5    25.0    -      -       +      +
    144A  ASN*     5.4     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  PRO*     3.8    21.4    -      -       +      +
     86A  LYS*     5.5     4.2    +      -       -      -
     89A  THR*     2.9    36.4    +      -       +      +
     90A  GLY*     3.1    15.6    +      -       -      +
     92A  LEU*     1.3    77.2    -      -       -      +
     94A  PHE*     1.4    59.6    +      -       -      +
     95A  GLU      3.4     0.5    +      -       -      -
     96A  VAL*     4.0     8.9    -      -       -      +
     97A  TYR*     3.6    18.8    -      -       +      -
    137A  THR      6.2     0.4    -      -       -      +
    139A  PRO*     4.0    18.6    -      -       +      -
    144A  ASN*     5.9     0.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  LEU*     4.5     7.0    -      -       +      -
     65A  PRO*     3.6    34.8    -      -       +      -
     90A  GLY      2.9    24.7    +      -       -      -
     91A  LEU*     3.1     9.6    +      -       -      +
     93A  GLU*     1.4    76.9    -      -       -      +
     95A  GLU*     1.4    66.9    +      -       -      +
     96A  VAL      3.3     0.7    -      -       -      -
     97A  TYR*     2.9    28.5    +      +       +      +
     98A  LEU*     3.0    18.0    +      -       +      +
    166A  ILE*     4.4     7.0    -      -       +      -
    169A  SER*     3.4    28.3    -      -       -      -
    170A  PHE*     3.6    56.8    -      +       +      -
    173A  PHE*     3.7    24.2    -      +       +      -
----------------------------------------------------------
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Residues in contact with GLU 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  LEU      3.4    15.9    -      -       -      +
     92A  LEU*     3.6    30.9    -      -       -      +
     93A  GLU      3.2     2.2    -      -       -      -
     94A  PHE*     1.4    77.1    -      -       -      +
     96A  VAL*     1.3    56.9    +      -       -      +
     98A  LEU*     3.0    11.1    +      -       +      +
     99A  GLU*     2.9    27.8    +      -       -      +
    116A  GLN*     4.7     2.9    -      -       -      +
    119A  THR*     4.8     8.7    -      -       +      -
    120A  LYS*     2.5    46.9    +      -       -      +
    123A  ILE*     4.0    14.4    -      -       +      +
    144A  ASN*     5.9     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92A  LEU      4.8     0.2    +      -       -      -
     93A  GLU      4.0     6.2    +      -       -      +
     95A  GLU*     1.3    77.9    -      -       -      +
     97A  TYR*     1.3    76.0    +      -       +      +
     99A  GLU*     3.2    10.5    +      -       -      +
    100A  TYR      2.9    22.5    +      -       -      -
    144A  ASN*     3.5    63.0    -      -       +      +
    147A  LEU*     3.9    25.6    -      -       +      -
    148A  LEU*     3.7    21.2    -      -       +      +
    151A  LEU*     6.2     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  LEU*     4.9    10.3    -      -       +      -
     63A  ASN*     4.0    22.3    +      -       -      +
     64A  LEU*     3.5    31.4    -      -       +      -
     65A  PRO*     4.6     7.2    -      -       +      -
     93A  GLU      3.6    21.5    -      -       -      -
     94A  PHE*     2.9    18.6    +      +       +      +
     96A  VAL*     1.3    83.6    -      -       +      +
     98A  LEU*     1.4    59.4    +      -       -      +
    100A  TYR*     3.3     7.5    +      -       -      +
    101A  LEU*     3.0    29.7    +      -       -      +
    147A  LEU*     3.6    29.7    -      -       +      +
    151A  LEU*     4.2    16.2    -      -       +      -
    166A  ILE*     3.8    34.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94A  PHE*     3.0    17.5    +      -       +      +
     95A  GLU*     3.7    11.7    -      -       +      +
     97A  TYR*     1.4    75.3    -      -       +      +
     99A  GLU*     1.4    65.0    +      -       -      +
    101A  LEU*     3.3    26.7    +      -       +      +
    102A  GLN*     3.1    22.3    +      -       -      +
    112A  ALA      4.8     2.1    -      -       -      +
    115A  VAL*     4.1     6.3    -      -       +      +
    116A  GLN*     4.0    28.5    -      -       +      +
    119A  THR*     3.6    40.2    -      -       +      +
    166A  ILE*     4.8     5.8    -      -       +      -
    170A  PHE*     3.8    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  GLU      2.9    12.3    +      -       -      +
     96A  VAL*     3.4    15.7    -      -       -      +
     98A  LEU*     1.4    73.2    -      -       -      +
    100A  TYR*     1.3    65.2    +      -       -      +
    102A  GLN*     3.1     3.6    +      -       +      +
    103A  ASN*     3.1    34.0    +      -       -      +
    116A  GLN*     3.4    20.0    +      -       -      +
    144A  ASN*     6.0     1.2    -      -       -      +
    148A  LEU*     3.4    28.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 100 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96A  VAL      2.9    10.3    +      -       -      +
     97A  TYR*     3.3    11.9    +      -       -      +
     99A  GLU*     1.3    74.2    -      -       -      +
    101A  LEU*     1.3    62.3    +      -       +      +
    103A  ASN*     3.2     3.6    +      -       -      +
    104A  ARG*     2.9    38.5    +      -       +      +
    148A  LEU*     3.5    17.1    -      -       +      +
    151A  LEU*     3.9    37.2    -      -       +      -
    152A  GLN*     4.1    17.5    -      -       +      +
    159A  GLN*     2.8    57.2    +      -       -      +
    162A  THR*     3.7    16.6    -      -       +      -
    163A  THR*     3.6    18.8    -      -       -      -
    166A  ILE*     3.6    19.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 101 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  LEU*     4.5    11.2    -      -       +      -
     97A  TYR      3.0    16.2    +      -       -      +
     98A  LEU*     3.5    31.4    -      -       +      +
     99A  GLU      3.3     0.2    -      -       -      -
    100A  TYR*     1.3    87.8    -      -       +      +
    102A  GLN*     1.3    58.4    +      -       -      +
    104A  ARG*     4.3     2.9    -      -       +      -
    105A  PHE*     2.9    44.8    +      -       +      -
    112A  ALA*     3.7     8.6    -      -       +      +
    115A  VAL*     5.4     3.6    -      -       +      -
    163A  THR*     4.0    33.2    -      -       +      +
    166A  ILE*     4.2    15.5    -      -       +      -
    167A  LEU*     3.9    23.3    -      -       +      -
    170A  PHE*     6.1     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 102 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98A  LEU      3.1    10.0    +      -       -      +
     99A  GLU*     3.1     8.5    +      -       +      +
    101A  LEU*     1.3    75.6    -      -       -      +
    103A  ASN*     1.3    82.1    +      -       -      +
    104A  ARG      3.5     0.3    +      -       -      -
    105A  PHE      3.6     5.2    -      -       -      +
    109A  GLU*     3.5    42.7    +      -       -      +
    112A  ALA*     3.6    10.1    -      -       +      +
    113A  ARG*     3.7    35.6    -      -       +      +
    116A  GLN*     3.2    32.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 103 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  GLU*     3.1    29.9    +      -       -      +
    100A  TYR      3.8     1.3    -      -       -      +
    102A  GLN*     1.3    94.9    +      -       -      +
    104A  ARG*     1.3    60.0    +      -       -      +
    105A  PHE      4.8     1.3    -      -       -      +
    106A  GLU*     5.0     8.0    -      -       -      +
    109A  GLU*     5.7     0.8    -      -       -      +
    148A  LEU*     4.1     4.5    -      -       -      +
    152A  GLN*     2.9    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 104 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100A  TYR*     2.9    30.0    +      -       +      +
    101A  LEU*     3.1     4.5    +      -       -      +
    103A  ASN*     1.3    80.1    -      -       -      +
    105A  PHE*     1.3    68.7    +      -       +      +
    106A  GLU*     3.4    10.7    +      -       -      +
    156A  GLN*     2.7    50.1    +      -       -      +
    159A  GLN*     3.5    36.1    +      -       -      +
    160A  ASP*     3.0    29.1    +      -       -      -
    163A  THR*     3.8    22.6    +      -       +      +
----------------------------------------------------------
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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