Contacts of the helix formed by residues 109 - 133 (chain P) in PDB entry 1PP9


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 PHE 109 (chain P).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106P  SER      3.0    10.5    +      -       -      +
    107P  TYR      2.9     2.5    -      -       -      -
    108P  THR*     1.3    78.1    +      -       -      +
    110P  LEU*     1.3    58.2    +      -       -      +
    111P  GLU*     3.5     5.4    -      -       -      -
    112P  THR*     3.4    17.3    +      -       -      +
    113P  TRP*     2.9    28.2    +      -       -      +
    200P  LEU*     3.9    15.5    -      -       +      -
    203P  THR*     3.3    33.4    -      -       +      +
    204P  GLY      3.4    26.5    -      -       -      -
    205P  SER      4.3     1.8    -      -       -      -
    206P  ASN*     3.8    16.6    -      -       +      -
    313P  ARG*     3.3    37.9    -      -       -      -
    502P  HEM      3.9    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 110 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107P  TYR      3.5    10.8    -      -       -      +
    108P  THR*     2.9    17.9    +      -       -      +
    109P  PHE*     1.3    70.1    -      -       -      +
    111P  GLU*     1.3    69.8    +      -       -      +
    113P  TRP*     3.8     0.8    -      -       -      +
    114P  ASN*     2.9    46.1    +      -       -      +
    305P  PRO*     3.4    36.1    -      -       +      -
    306P  LEU*     6.3     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 111 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109P  PHE*     4.3     2.8    -      -       -      -
    110P  LEU*     1.3    85.1    +      -       +      +
    112P  THR*     1.3    66.8    +      -       -      +
    114P  ASN*     3.9     2.9    -      -       -      +
    115P  ILE*     3.0    33.3    +      -       +      +
    199P  PHE*     3.5    41.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 112 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109P  PHE*     3.4    20.0    +      -       -      +
    111P  GLU*     1.3    79.2    +      -       -      +
    113P  TRP*     1.3    64.6    +      -       -      +
    115P  ILE*     3.4     1.9    +      -       -      +
    116P  GLY      3.0    17.0    +      -       -      -
    196P  HIS*     3.1    45.6    +      -       +      +
    199P  PHE*     3.5    10.2    +      -       -      +
    200P  LEU*     3.2    34.6    +      -       +      -
    502P  HEM      3.7    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 113 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98P  VAL*     4.3     9.0    -      -       +      -
    101P  GLY*     4.1    21.1    -      -       -      -
    102P  LEU*     3.6    35.9    -      -       +      -
    107P  TYR*     3.2    36.3    -      -       +      +
    109P  PHE      2.9    18.8    +      -       -      +
    110P  LEU      3.8     2.7    -      -       -      +
    112P  THR*     1.3    77.1    -      -       -      +
    114P  ASN*     1.3    73.3    +      -       -      +
    116P  GLY*     2.9    18.0    +      -       -      -
    117P  VAL*     3.0    15.0    +      -       +      +
    301P  LEU*     2.7    40.7    +      -       +      -
    304P  ILE*     4.5     2.0    -      -       +      -
    305P  PRO*     4.0    18.4    -      -       +      +
    502P  HEM      3.8    51.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 114 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110P  LEU*     2.9    36.9    +      -       -      +
    111P  GLU*     4.2     4.4    -      -       -      +
    113P  TRP*     1.3    87.2    -      -       -      +
    115P  ILE*     1.3    62.5    +      -       +      +
    117P  VAL*     3.2    16.2    +      -       -      +
    118P  ILE*     3.2    20.6    +      -       +      +
    302P  ALA*     4.0    24.9    +      -       -      +
    305P  PRO*     5.5     0.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 115 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111P  GLU*     3.0    20.8    +      -       +      +
    112P  THR      3.6     3.8    -      -       -      +
    114P  ASN*     1.3    76.8    -      -       +      +
    116P  GLY*     1.3    58.7    +      -       -      +
    118P  ILE*     3.1    15.3    +      -       +      +
    119P  LEU*     2.8    26.6    +      -       +      +
    192P  ILE*     3.7    34.8    -      -       +      +
    195P  VAL*     3.6    21.1    -      -       +      +
    196P  HIS*     3.8    17.0    -      -       +      +
    199P  PHE*     3.3    36.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 116 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112P  THR      3.0    11.1    +      -       -      -
    113P  TRP      2.9     9.6    +      -       -      -
    115P  ILE*     1.3    78.4    -      -       -      +
    117P  VAL*     1.3    56.9    +      -       -      +
    119P  LEU*     3.1     4.5    +      -       -      +
    120P  LEU      2.9    24.8    +      -       -      -
    196P  HIS*     3.9     4.0    -      -       -      -
    502P  HEM      3.0    42.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 117 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113P  TRP*     3.0    23.1    +      -       +      +
    114P  ASN*     3.2    12.5    +      -       -      +
    116P  GLY*     1.3    75.7    -      -       -      +
    118P  ILE*     1.3    64.7    +      -       +      +
    120P  LEU*     3.3     6.3    +      -       -      +
    121P  LEU*     3.2    34.9    +      -       +      +
    298P  ILE*     4.6    17.0    -      -       +      +
    299P  LEU*     4.8     9.6    -      -       +      -
    301P  LEU*     4.0    20.4    -      -       +      -
    302P  ALA*     4.3    15.7    -      -       +      +
    502P  HEM      3.8    16.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 118 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114P  ASN*     3.2    15.7    +      -       +      +
    115P  ILE*     3.1    17.9    +      -       +      +
    117P  VAL*     1.3    77.0    -      -       +      +
    119P  LEU*     1.3    62.6    +      -       -      +
    121P  LEU*     3.3    11.8    +      -       +      +
    122P  THR*     2.8    38.9    +      -       -      +
    192P  ILE*     4.4    21.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 119 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115P  ILE*     2.8    19.0    +      -       +      +
    116P  GLY*     3.1     8.9    +      -       -      +
    118P  ILE*     1.3    77.8    -      -       -      +
    120P  LEU*     1.3    60.6    +      -       -      +
    122P  THR*     3.3     4.3    +      -       -      -
    123P  VAL*     2.9    30.7    +      -       -      +
    189P  ILE*     3.7    35.9    -      -       +      +
    192P  ILE*     3.5    24.9    -      -       +      -
    193P  ALA*     3.9     5.4    -      -       -      +
    196P  HIS*     3.8    37.5    -      -       +      +
    502P  HEM      4.0    33.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 120 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91P  PHE*     5.0     0.4    -      -       +      -
     94P  LEU*     4.0    29.2    -      -       +      -
     95P  TYR*     4.4    14.1    -      -       +      -
     98P  VAL*     4.7    10.3    -      -       +      -
    116P  GLY      2.9     6.4    +      -       -      +
    117P  VAL*     3.6     8.7    -      -       -      +
    118P  ILE      3.3     0.2    -      -       -      -
    119P  LEU*     1.3    75.5    -      -       -      +
    121P  LEU*     1.3    57.9    +      -       -      +
    123P  VAL*     3.4     3.9    +      -       -      +
    124P  MET*     3.0    57.9    +      -       +      +
    298P  ILE*     4.2    13.7    -      -       +      -
    301P  LEU*     3.7    31.0    -      -       +      -
    502P  HEM      3.7    17.1    -      -       +      +
   3007P  PEE      5.0     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 121 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117P  VAL*     3.2    21.3    +      -       +      +
    118P  ILE*     3.7    10.8    -      -       +      +
    120P  LEU*     1.3    75.7    -      -       -      +
    122P  THR*     1.3    61.8    +      -       -      +
    124P  MET*     3.4     5.1    +      -       -      -
    125P  ALA*     3.0    25.1    +      -       -      +
    298P  ILE*     3.6    32.8    -      -       +      -
    299P  LEU*     4.1    25.1    -      -       +      -
   3001P  SMA      3.5    32.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 122 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118P  ILE*     2.8    28.0    +      -       -      +
    119P  LEU*     3.3     5.8    +      -       -      -
    121P  LEU*     1.3    73.0    -      -       -      +
    123P  VAL*     1.3    60.5    +      -       -      +
    125P  ALA*     3.3     5.5    +      -       -      +
    126P  THR*     2.8    33.5    +      -       -      -
    185P  LEU*     3.5    28.5    -      -       +      -
    188P  ILE*     5.3     0.2    -      -       +      -
    189P  ILE*     3.2    29.2    -      -       +      -
    192P  ILE*     4.6    10.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 123 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90P  PHE*     4.0    37.7    -      -       +      -
     91P  PHE*     3.9    13.9    -      -       +      -
     94P  LEU*     3.7    24.7    -      -       +      -
    119P  LEU      2.9    21.5    +      -       -      +
    120P  LEU      3.9     3.6    -      -       -      +
    122P  THR*     1.3    73.0    -      -       -      +
    124P  MET*     1.3    61.5    +      -       -      +
    126P  THR*     3.6     1.5    -      -       -      -
    127P  ALA*     2.9    28.6    +      -       -      +
    189P  ILE*     3.8    20.6    -      -       +      -
    501P  HEM      4.6     7.4    -      -       +      -
    502P  HEM      4.2    12.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 124 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91P  PHE*     3.9    21.5    -      -       +      -
     95P  TYR*     3.8    22.7    -      -       +      +
    120P  LEU*     3.0    43.3    +      -       +      +
    121P  LEU*     3.6     8.7    -      -       -      +
    122P  THR      3.3     0.2    -      -       -      -
    123P  VAL*     1.3    77.4    -      -       -      +
    125P  ALA*     1.3    63.5    +      -       -      +
    127P  ALA      3.9     0.2    -      -       -      -
    128P  PHE*     3.0    23.7    +      -       -      +
    274P  PHE*     3.7    17.6    -      -       +      -
    276P  PHE*     4.6     6.5    -      -       +      -
    298P  ILE*     3.7    33.2    -      -       +      -
   3001P  SMA      3.9    37.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 125 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121P  LEU      3.0    17.1    +      -       -      +
    122P  THR*     3.7     6.5    -      -       -      +
    124P  MET*     1.3    75.6    -      -       -      +
    126P  THR*     1.3    61.8    +      -       -      +
    128P  PHE*     3.3     6.9    +      -       -      +
    129P  MET*     3.1    32.1    +      -       -      +
    185P  LEU*     4.5    11.7    -      -       +      -
   3001P  SMA      3.8    33.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 126 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122P  THR      2.8    23.1    +      -       -      -
    123P  VAL*     3.6     8.1    -      -       -      -
    124P  MET      3.2     0.2    -      -       -      -
    125P  ALA*     1.3    75.7    -      -       -      +
    127P  ALA*     1.3    61.3    +      -       -      +
    129P  MET*     3.3     5.1    +      -       -      -
    130P  GLY      3.1     6.2    +      -       -      -
    182P  HIS*     2.9    44.9    +      -       +      +
    185P  LEU*     3.0    28.6    -      -       +      +
    186P  PRO*     3.9    13.5    -      -       +      -
    189P  ILE*     3.4     6.8    -      -       -      +
    501P  HEM      3.8    26.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 127 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87P  ALA*     5.3     0.4    -      -       +      -
     91P  PHE*     3.7    26.9    -      -       +      -
    123P  VAL      2.9    20.3    +      -       -      +
    124P  MET      3.9     3.4    -      -       -      +
    126P  THR*     1.3    71.4    -      -       -      +
    128P  PHE*     1.3    64.8    +      -       -      +
    130P  GLY      3.3     0.3    +      -       -      -
    131P  TYR*     3.1    23.7    +      -       -      +
    271P  GLU*     5.3     0.9    -      -       -      -
    273P  TYR*     4.2    15.3    +      -       +      +
    274P  PHE*     4.8     0.9    -      -       +      -
    501P  HEM      3.7    28.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 128 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124P  MET      3.0    14.3    +      -       -      +
    125P  ALA      3.4     6.7    -      -       -      +
    126P  THR      3.2     0.2    -      -       -      -
    127P  ALA*     1.3    78.9    -      -       -      +
    129P  MET*     1.3    74.9    +      -       +      +
    131P  TYR*     3.1    15.0    +      +       +      +
    132P  VAL*     3.4    13.3    +      -       +      +
    142P  GLY*     3.4    28.0    -      -       -      -
    143P  ALA*     3.8     9.4    -      -       -      -
    146P  ILE*     3.4    40.2    -      -       +      -
    147P  THR*     4.2     5.8    -      -       -      -
    178P  PHE*     3.7    26.2    -      +       -      -
    271P  GLU*     4.7     5.2    -      -       -      -
    274P  PHE*     4.5    10.7    -      -       +      -
   3001P  SMA      3.8    44.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 129 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125P  ALA*     3.1    19.8    +      -       -      +
    126P  THR*     3.8     4.3    -      -       -      +
    128P  PHE*     1.3    90.0    -      -       +      +
    130P  GLY*     1.3    62.9    +      -       -      +
    132P  VAL*     3.2    14.3    +      -       -      +
    133P  LEU*     3.4    16.4    -      -       -      +
    178P  PHE*     3.4    34.1    -      -       +      +
    181P  PHE*     2.9    53.4    -      -       +      -
    182P  HIS*     4.1    15.5    -      -       +      +
    185P  LEU*     4.7    10.8    -      -       -      -
   3001P  SMA      3.7    20.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 130 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126P  THR      3.1    11.1    +      -       -      -
    127P  ALA      3.3     1.7    +      -       -      -
    128P  PHE      3.2     0.2    -      -       -      -
    129P  MET*     1.3    76.0    -      -       -      +
    131P  TYR*     1.3    63.3    -      -       -      +
    133P  LEU*     3.1    21.7    +      -       -      +
    134P  PRO*     3.4     5.4    -      -       -      +
    182P  HIS*     3.3    30.2    +      -       -      -
    501P  HEM      3.4    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 131 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127P  ALA      3.1    11.7    +      -       -      +
    128P  PHE*     3.1    11.9    +      +       +      +
    130P  GLY*     1.3    76.3    -      -       -      +
    132P  VAL*     1.3    53.4    +      -       +      +
    134P  PRO*     3.2     7.8    -      -       -      +
    138P  MET*     3.6    42.5    -      -       +      +
    139P  SER*     2.6    28.4    +      -       -      -
    142P  GLY*     6.0     2.0    -      -       -      -
    252P  ASP*     3.6    23.3    +      -       -      +
    255P  ASN*     3.8    19.2    -      -       +      +
    269P  LYS      6.1     0.4    -      -       -      -
    270P  PRO      6.1     0.2    -      -       -      -
    271P  GLU*     3.4    38.2    -      -       +      +
    273P  TYR*     5.6     0.2    -      -       -      +
    501P  HEM      3.7    22.7    -      -       +      -
   3001P  SMA      4.9     3.6    -      -       -      -
   3009P  GOL      3.6    35.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 132 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128P  PHE*     3.6    35.0    -      -       +      +
    129P  MET      3.2     8.0    +      -       -      +
    130P  GLY      3.1     0.8    -      -       -      -
    131P  TYR*     1.3    78.2    -      -       +      +
    133P  LEU*     1.3    65.9    +      -       -      +
    134P  PRO      3.4     0.2    -      -       -      -
    135P  TRP*     3.0    42.1    +      -       +      -
    139P  SER*     3.2    28.0    -      -       -      +
    142P  GLY*     4.9     0.7    -      -       -      -
    143P  ALA*     3.8    11.7    -      -       +      +
    174P  THR*     5.7     0.9    -      -       +      -
    175P  LEU*     4.3     7.6    -      -       +      -
    178P  PHE*     4.0    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 133 (chain P). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55P  TYR*     2.7    40.5    +      -       +      +
     62P  ALA*     3.7     6.6    -      -       -      +
    129P  MET      3.4    14.4    -      -       -      +
    130P  GLY      3.1     9.5    +      -       -      +
    132P  VAL*     1.3    76.2    -      -       -      +
    134P  PRO*     1.3    62.9    -      -       +      +
    135P  TRP      3.0     1.3    +      -       -      -
    175P  LEU*     3.8    14.1    -      -       +      +
    178P  PHE*     4.0     4.7    -      -       +      -
    179P  PHE*     3.7    43.3    -      -       +      +
    182P  HIS*     3.7    33.4    -      -       +      -
    501P  HEM      3.7    25.8    -      -       +      -
----------------------------------------------------------
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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