Contacts of the helix formed by residues 116 - 141 (chain D) in PDB entry 2NP5


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 SER 116 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112D  ARG*     3.1    32.2    +      -       -      -
    113D  ALA      3.5     6.9    +      -       -      +
    115D  THR*     1.3    80.1    -      -       -      +
    117D  PRO*     1.4    61.7    -      -       -      +
    118D  SER*     3.5     7.8    +      -       -      -
    119D  LEU*     3.0    32.0    +      -       -      +
    120D  ALA      2.9    24.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with PRO 117 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115D  THR      3.7     7.0    -      -       -      +
    116D  SER*     1.4    86.5    -      -       -      +
    118D  SER*     1.3    57.3    +      -       -      +
    120D  ALA*     3.6     8.9    -      -       +      +
    121D  GLU*     3.0    26.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 118 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  ARG*     4.3    10.6    +      -       -      +
     54D  ASP*     5.5     7.2    -      -       -      +
    116D  SER*     3.5     9.9    +      -       -      -
    117D  PRO*     1.3    78.6    -      -       -      +
    119D  LEU*     1.3    72.7    +      -       -      +
    121D  GLU*     3.4     7.6    +      -       -      +
    122D  ILE*     3.3    29.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 119 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27D  LEU*     5.4     2.0    -      -       +      -
     54D  ASP*     5.6     9.9    -      -       +      -
     57D  PHE*     6.2     1.8    -      -       +      -
    109D  PHE*     3.5    41.5    -      -       +      -
    112D  ARG*     3.3    40.4    -      -       +      +
    113D  ALA*     4.2     9.0    -      -       -      -
    116D  SER*     3.0    27.9    +      -       -      +
    118D  SER*     1.3    86.1    +      -       -      +
    120D  ALA*     1.3    55.0    +      -       -      +
    122D  ILE*     3.2     7.9    +      -       +      -
    123D  ARG*     2.8    35.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 120 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    166B  GLY      3.4    24.5    -      -       -      +
    167B  SER*     4.0     2.8    +      -       -      -
    113D  ALA*     3.5    26.8    -      -       +      +
    116D  SER      2.9     7.4    +      -       -      +
    117D  PRO*     3.6    13.2    -      -       +      +
    119D  LEU*     1.3    76.7    -      -       -      +
    121D  GLU*     1.3    51.0    +      -       -      +
    123D  ARG*     3.3     3.0    +      -       -      +
    124D  ARG*     2.7    36.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 121 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  ARG*     3.9    23.1    -      -       -      +
     78C  GLY*     3.7    17.5    +      -       -      -
    117D  PRO      3.0    14.7    +      -       -      +
    118D  SER*     3.7    10.3    -      -       -      +
    119D  LEU      3.3     0.4    -      -       -      -
    120D  ALA*     1.3    75.3    -      -       -      +
    122D  ILE*     1.3    62.9    +      -       -      +
    124D  ARG*     2.8    45.3    +      -       -      +
    125D  LYS*     3.0    37.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 122 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  ARG*     3.7    33.4    -      -       -      +
     54D  ASP*     3.9    30.3    -      -       +      +
     57D  PHE*     5.5     0.7    -      -       +      -
     58D  ALA*     4.0    23.6    -      -       +      +
     61D  LEU*     3.8    24.5    -      -       +      -
    109D  PHE*     3.8    10.8    -      -       +      -
    118D  SER      3.3    14.7    +      -       -      +
    119D  LEU*     3.2    13.3    +      -       +      +
    121D  GLU*     1.3    76.0    -      -       -      +
    123D  ARG*     1.3    56.7    +      -       -      +
    125D  LYS*     3.4     5.7    +      -       -      +
    126D  THR*     2.7    34.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 123 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162B  LEU*     4.4     8.3    +      -       -      +
    163B  ASP*     2.8    38.2    +      -       -      +
    166B  GLY*     5.6     3.4    -      -       -      -
    167B  SER*     4.4     3.8    +      -       -      +
     61D  LEU*     4.9     1.3    -      -       +      -
    106D  MSE      4.2    25.7    +      -       -      +
    109D  PHE*     3.8    19.7    -      -       +      -
    110D  ALA*     3.2    43.9    +      -       -      +
    113D  ALA*     4.5     7.0    -      -       +      -
    119D  LEU      2.8    16.5    +      -       -      +
    120D  ALA*     3.7     7.0    -      -       -      +
    122D  ILE*     1.3    75.0    -      -       -      +
    124D  ARG*     1.3    60.0    +      -       -      +
    126D  THR*     3.1    10.3    +      -       -      +
    127D  LEU*     2.8    53.1    +      -       +      +
    158D  ASP*     3.7    11.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 124 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167B  SER*     3.5    23.9    +      -       -      +
    169B  ALA*     5.3     8.3    -      -       -      -
    170B  LEU*     3.9    32.9    -      -       +      +
     78C  GLY*     5.4     2.2    -      -       -      -
    140C  GLY*     6.3     1.2    -      -       -      -
    120D  ALA      2.7    21.4    +      -       -      +
    121D  GLU*     2.8    45.2    +      -       -      +
    123D  ARG*     1.3    72.3    -      -       -      +
    125D  LYS*     1.3    87.0    +      -       -      +
    127D  LEU*     3.4     4.4    +      -       -      +
    128D  PHE*     2.9    41.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 125 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76C  GLU      6.0     2.0    -      -       -      +
     77C  ARG*     6.0     1.6    -      -       -      +
     78C  GLY*     5.4     7.0    -      -       -      +
    136C  ALA*     4.4     5.8    +      -       -      -
    137C  VAL*     4.0    35.6    -      -       -      +
    140C  GLY*     6.0     1.4    -      -       -      -
    121D  GLU*     3.0    33.8    +      -       +      +
    122D  ILE*     3.7     6.1    -      -       -      +
    124D  ARG*     1.3   108.9    -      -       -      +
    126D  THR*     1.3    59.1    +      -       -      +
    128D  PHE*     3.3     9.2    +      -       -      +
    129D  THR*     2.9    43.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 126 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61D  LEU*     3.8    28.9    -      -       +      +
     64D  LEU*     5.9     0.7    -      -       +      -
     65D  VAL*     3.4    28.6    -      -       +      +
    106D  MSE      4.7    14.1    -      -       +      -
    122D  ILE*     2.7    21.3    +      -       -      +
    123D  ARG*     3.3    13.7    -      -       +      +
    125D  LYS*     1.3    77.2    -      -       -      +
    127D  LEU*     1.3    67.2    +      -       +      +
    129D  THR*     3.3     3.1    +      -       -      -
    130D  ILE*     3.1    38.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 127 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163B  ASP*     3.9    28.7    -      -       +      +
    167B  SER*     4.1    16.8    -      -       -      +
    170B  LEU*     4.6     4.3    -      -       +      -
    171B  TYR*     4.0    21.5    -      -       +      +
    123D  ARG*     2.8    47.3    +      -       -      +
    124D  ARG*     3.7     4.5    -      -       -      +
    126D  THR*     1.3    77.7    -      -       +      +
    128D  PHE*     1.3    56.7    +      -       -      +
    130D  ILE*     3.3     3.0    +      -       +      -
    131D  ARG*     2.9    34.6    +      -       -      +
    154D  LEU*     3.7    18.9    -      -       +      +
    158D  ASP*     3.7    22.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 128 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170B  LEU*     3.7    35.6    -      -       +      +
    136C  ALA*     3.3    31.0    -      -       +      -
    139C  ILE*     3.9    22.4    -      -       +      -
    140C  GLY*     4.0    15.9    -      -       -      -
    124D  ARG*     2.9    26.6    +      -       -      +
    125D  LYS*     3.9    11.4    -      -       -      +
    127D  LEU*     1.3    76.6    -      -       -      +
    129D  THR*     1.3    58.1    +      -       -      +
    131D  ARG*     3.4    23.6    +      -       +      +
    132D  THR*     2.9    45.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 129 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132C  THR*     3.8     8.2    -      -       +      +
    133C  GLY*     4.3    20.8    +      -       -      -
    136C  ALA*     3.8    17.1    -      -       -      +
     65D  VAL*     3.8    23.1    -      -       +      -
     69D  LEU*     4.1    15.6    -      -       +      +
    125D  LYS*     2.9    26.1    +      -       -      +
    126D  THR*     3.8     3.8    -      -       -      -
    128D  PHE*     1.3    75.1    -      -       -      +
    130D  ILE*     1.3    66.7    +      -       -      +
    132D  THR*     3.3     3.1    +      -       -      -
    133D  GLY*     3.2    17.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 130 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64D  LEU*     6.0     3.1    -      -       +      -
     65D  VAL*     4.1    20.4    -      -       +      -
     68D  LEU*     3.8    35.9    -      -       +      -
     69D  LEU*     4.7     7.4    -      -       +      -
     72D  LEU*     4.5     3.9    -      -       +      +
     89D  MSE      4.1     3.1    -      -       +      -
     92D  LEU*     5.0     5.2    -      -       +      -
    126D  THR*     3.1    34.3    +      -       +      +
    127D  LEU*     3.7     6.1    -      -       +      +
    129D  THR*     1.3    75.6    -      -       -      +
    131D  ARG*     1.3    57.6    +      -       -      +
    133D  GLY*     3.2     3.5    +      -       -      -
    134D  LEU*     2.9    41.1    +      -       +      +
    154D  LEU*     3.6    30.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 131 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170B  LEU*     3.6    25.1    +      -       -      +
    171B  TYR*     3.1    40.2    +      -       -      -
    175B  TYR*     3.6    21.2    +      -       -      -
    127D  LEU      2.9    23.7    +      -       -      +
    128D  PHE*     3.7    26.1    -      -       +      +
    129D  THR      3.3     0.2    -      -       -      -
    130D  ILE*     1.3    74.7    -      -       -      +
    132D  THR*     1.3    56.2    +      -       -      +
    134D  LEU*     3.7     7.2    -      -       -      +
    135D  SER*     2.8    38.6    +      -       -      -
    147D  GLU*     5.1     4.6    +      -       -      +
    150D  ALA*     4.0     5.4    -      -       +      +
    151D  ALA*     3.6    32.9    -      -       -      +
    154D  LEU*     3.8    15.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 132 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132C  THR*     4.0     9.2    -      -       +      +
    135C  SER*     4.0    19.5    -      -       -      -
    136C  ALA*     3.4    22.0    -      -       -      +
    139C  ILE*     3.7    26.0    -      -       +      +
    147C  GLU*     4.7     6.8    -      -       -      +
    128D  PHE*     2.9    34.1    +      -       -      -
    129D  THR      3.6     5.4    -      -       -      -
    130D  ILE      3.3     0.4    -      -       -      -
    131D  ARG*     1.3    73.4    -      -       -      +
    133D  GLY*     1.3    57.9    +      -       -      +
    135D  SER*     3.2     9.5    +      -       -      +
    136D  ALA*     3.0    28.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 133 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128C  PHE*     5.2     6.5    -      -       -      -
    132C  THR*     3.7    19.1    -      -       -      +
     69D  LEU*     4.4     3.8    -      -       -      -
     72D  LEU*     3.7    14.9    -      -       -      +
    129D  THR      3.2    11.8    +      -       -      -
    130D  ILE      3.2     2.9    +      -       -      -
    132D  THR*     1.3    75.7    -      -       -      +
    134D  LEU*     1.3    62.4    +      -       -      +
    136D  ALA*     3.4     6.8    +      -       -      +
    137D  VAL*     3.3    24.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 134 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72D  LEU*     3.7    21.0    -      -       +      +
     85D  LEU*     3.7    26.1    -      -       +      +
     89D  MSE      4.1    21.3    -      -       +      -
    130D  ILE*     2.9    40.2    +      -       +      +
    131D  ARG*     3.7     5.2    -      -       -      +
    133D  GLY*     1.3    74.9    -      -       -      +
    135D  SER*     1.3    64.0    +      -       -      +
    137D  VAL*     3.1     9.1    +      -       -      +
    138D  LEU*     3.1    24.7    +      -       +      +
    150D  ALA*     3.8    32.1    -      -       +      +
    153D  LEU*     4.2    10.5    -      -       +      -
    154D  LEU*     4.1    13.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 135 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139C  ILE*     5.9     1.6    -      -       -      +
    131D  ARG      2.8    26.1    +      -       -      -
    132D  THR*     3.2    12.1    +      -       -      +
    134D  LEU*     1.3    73.4    -      -       -      +
    136D  ALA*     1.3    56.8    +      -       -      +
    138D  LEU*     3.2     5.4    +      -       -      +
    139D  ILE*     2.7    42.1    +      -       -      +
    146D  ALA      4.2     1.1    -      -       -      -
    147D  GLU*     4.1    29.8    +      -       -      +
    150D  ALA*     3.6    18.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 136 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128C  PHE*     6.1     5.2    -      -       +      -
    147C  GLU*     3.6    21.3    -      -       -      +
    132D  THR*     3.0    17.8    +      -       +      +
    133D  GLY*     3.7     7.4    -      -       -      +
    134D  LEU      3.2     0.2    -      -       -      -
    135D  SER*     1.3    77.1    +      -       -      +
    137D  VAL*     1.3    63.3    +      -       +      +
    139D  ILE*     3.9     7.9    -      -       -      +
    140D  GLY*     3.1    20.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 137 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128C  PHE*     5.5     4.7    -      -       +      -
     72D  LEU*     4.2    33.0    -      -       +      +
     75D  VAL*     4.1    31.0    -      -       +      +
     81D  PRO*     4.3    18.6    -      -       +      -
     85D  LEU*     4.4    20.4    -      -       +      -
    133D  GLY      3.3    13.7    +      -       -      +
    134D  LEU      3.1     7.7    +      -       -      +
    136D  ALA*     1.3    75.8    -      -       +      +
    138D  LEU*     1.3    66.6    +      -       +      +
    140D  GLY*     3.2    11.3    +      -       -      -
    141D  ILE*     3.4    15.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 138 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85D  LEU*     4.1    15.3    -      -       +      -
    134D  LEU*     3.1    11.1    +      -       +      +
    135D  SER      3.7     6.7    -      -       -      +
    137D  VAL*     1.3    75.8    -      -       +      +
    139D  ILE*     1.3    62.1    +      -       -      +
    141D  ILE*     3.4     4.3    -      -       +      +
    142D  GLY      3.3     3.1    +      -       -      -
    143D  THR*     2.7    46.2    +      -       +      +
    146D  ALA*     3.6    26.0    -      -       +      +
    149D  ARG*     4.1     4.9    -      -       +      -
    150D  ALA*     3.8    19.5    -      -       +      +
    153D  LEU*     5.9     2.7    -      -       +      -
    187D  ILE*     3.6    26.9    -      -       +      -
    188D  LEU*     3.7    30.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 139 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147C  GLU*     5.0    11.4    -      -       -      +
    135D  SER*     2.7    39.1    +      -       -      +
    136D  ALA*     3.9     7.6    -      -       -      +
    138D  LEU*     1.3    72.3    -      -       -      +
    140D  GLY*     1.3    58.9    +      -       -      +
    142D  GLY*     2.9    20.2    +      -       -      +
    143D  THR      4.8     1.6    -      -       -      +
    146D  ALA*     3.6    20.2    -      -       +      -
    147D  GLU*     4.7    14.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 140 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136D  ALA      3.1    14.8    +      -       -      -
    137D  VAL*     3.2     5.3    +      -       -      -
    139D  ILE*     1.3    77.5    -      -       -      +
    141D  ILE*     1.3    63.2    +      -       -      +
    142D  GLY      3.5     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 141 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  VAL*     5.7     3.8    -      -       +      -
     81D  PRO*     4.0    33.9    -      -       +      -
    137D  VAL*     3.4    12.8    +      -       +      +
    138D  LEU*     3.4     7.0    -      -       +      +
    140D  GLY*     1.3    80.8    -      -       -      +
    142D  GLY*     1.3    61.6    +      -       -      +
    143D  THR*     3.3    16.4    -      -       -      +
    188D  LEU*     3.6    32.1    -      -       +      -
    191D  ALA*     3.8     8.1    -      -       +      -
    192D  ASP*     2.9    48.6    +      -       +      +
----------------------------------------------------------
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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