Contacts of the helix formed by residues 92 - 117 (chain D) in PDB entry 3ECS


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 ILE 92 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78D  LEU*     3.3    33.9    -      -       +      -
     90D  LYS      2.9    15.2    +      -       -      +
     91D  LYS*     1.3    70.0    -      -       -      +
     93D  MSE      1.3    66.1    +      -       -      +
     94D  ILE      3.4     0.9    -      -       -      -
     95D  GLU*     3.5    23.6    +      -       -      +
     96D  ARG*     3.3    42.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with MSE 93 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34D  LEU*     4.1    12.3    -      -       +      -
     43D  GLN*     5.9     4.5    -      -       +      +
     46D  ARG*     4.9    20.9    -      -       -      -
     76D  ILE*     3.2    48.7    -      -       +      +
     77D  SER*     4.1    15.0    -      -       -      +
     78D  LEU*     4.2    20.6    -      -       +      +
     91D  LYS*     2.9    25.8    -      -       +      -
     92D  ILE*     1.3    84.2    -      -       +      +
     94D  ILE*     1.3    55.6    +      -       -      +
     96D  ARG*     3.1     3.5    +      -       -      +
     97D  GLY      2.7    31.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 94 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31D  LEU*     4.2     5.7    -      -       +      +
     34D  LEU*     3.8    22.2    -      -       +      -
     35D  LYS*     3.7    52.0    -      -       +      +
     91D  LYS*     3.6    35.0    +      -       +      +
     92D  ILE      3.4     0.2    -      -       -      -
     93D  MSE      1.3    75.3    -      -       -      +
     95D  GLU*     1.3    62.4    +      -       -      +
     97D  GLY*     3.2     1.3    +      -       -      +
     98D  GLU*     3.0    30.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 95 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92D  ILE*     3.5    27.4    +      -       -      +
     93D  MSE      3.2     0.6    -      -       -      -
     94D  ILE*     1.3    74.9    -      -       -      +
     96D  ARG*     1.3    67.2    +      -       +      +
     98D  GLU*     3.2    13.3    +      -       -      +
     99D  LEU*     3.1    19.7    +      -       +      +
    102D  ARG*     5.0     3.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 96 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  PHE*     3.6    34.0    +      -       +      +
     76D  ILE*     2.9    18.6    +      -       -      -
     77D  SER      2.6    33.7    +      -       -      -
     78D  LEU*     3.4    24.6    -      -       -      +
     92D  ILE*     3.3    29.2    +      -       +      +
     93D  MSE      3.1     6.1    +      -       -      +
     95D  GLU*     1.3    78.2    -      -       +      +
     97D  GLY*     1.3    64.8    +      -       -      +
     99D  LEU*     3.0    13.2    +      -       +      +
    100D  PHE*     2.9    24.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 97 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31D  LEU*     4.4     7.2    -      -       -      -
     72D  PHE*     3.6    28.9    -      -       -      -
     75D  PHE*     5.6     0.2    -      -       -      -
     76D  ILE*     4.0     6.9    -      -       -      +
     93D  MSE      2.7    21.4    +      -       -      -
     94D  ILE      3.5     2.9    -      -       -      -
     95D  GLU      3.1     0.4    -      -       -      -
     96D  ARG*     1.3    72.7    -      -       -      +
     98D  GLU*     1.3    56.1    -      -       -      +
    100D  PHE*     3.4     4.8    +      -       -      +
    101D  LEU*     3.0    27.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 98 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31D  LEU*     3.5    19.7    -      -       +      -
     35D  LYS*     2.7    30.5    +      -       -      -
     94D  ILE*     3.0    24.9    +      -       -      +
     95D  GLU*     3.2    10.4    +      -       -      +
     97D  GLY*     1.3    71.8    -      -       -      +
     99D  LEU*     1.3    60.3    +      -       -      +
    101D  LEU*     3.3     9.3    +      -       +      +
    102D  ARG*     2.8    45.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 99 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  PHE*     4.2    14.4    -      -       +      -
     95D  GLU*     3.1    10.7    +      -       +      +
     96D  ARG*     3.0    13.3    +      -       +      +
     98D  GLU*     1.3    73.3    -      -       -      +
    100D  PHE*     1.3    66.9    +      -       -      +
    102D  ARG*     3.0    36.6    +      -       +      +
    103D  ARG*     3.1    54.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 100 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27D  ILE*     3.4    33.7    -      -       +      -
     68D  GLY      4.2     3.1    -      -       -      -
     71D  LEU*     3.8    30.5    -      -       +      -
     72D  PHE*     3.7    31.9    -      +       +      -
     75D  PHE*     3.4    43.9    -      +       +      -
     96D  ARG      2.9     6.1    +      -       -      +
     97D  GLY*     3.5     7.9    -      -       -      +
     99D  LEU*     1.3    76.6    -      -       -      +
    101D  LEU*     1.3    63.2    +      -       -      +
    103D  ARG*     3.1    16.9    +      -       -      +
    104D  ILE*     3.2    41.7    +      -       +      +
    233D  PHE*     5.1     7.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 101 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24D  VAL*     4.6     3.1    -      -       +      -
     27D  ILE*     3.3    33.0    -      -       +      -
     28D  ARG*     2.8    59.5    +      -       +      +
     31D  LEU*     3.6    29.2    -      -       +      -
     97D  GLY      3.0    11.3    +      -       -      +
     98D  GLU*     3.4    10.5    -      -       +      +
    100D  PHE*     1.3    79.4    -      -       -      +
    102D  ARG*     1.3    61.1    +      -       -      +
    103D  ARG      3.5     0.2    +      -       -      -
    104D  ILE*     3.5    15.9    -      -       +      +
    105D  SER*     3.5    11.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 102 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95D  GLU*     5.0     3.0    +      -       -      +
     98D  GLU*     2.8    22.1    +      -       -      +
     99D  LEU*     3.0    43.4    +      -       +      +
    101D  LEU*     1.3    78.4    -      -       -      +
    103D  ARG*     1.3    60.4    +      -       +      +
    105D  SER*     2.8    19.6    +      -       -      +
    106D  LEU*     4.0    13.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 103 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  PHE*     4.1    20.5    -      -       -      -
     99D  LEU*     3.1    53.3    +      -       +      +
    100D  PHE*     3.1     8.0    +      -       -      +
    102D  ARG*     1.3    75.7    -      -       +      +
    104D  ILE*     1.3    58.4    +      -       +      +
    105D  SER      3.0     4.7    -      -       -      -
    106D  LEU*     2.8    36.6    +      -       +      +
    107D  SER*     3.5     5.6    +      -       -      -
    110D  LYS*     4.7     1.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 104 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23D  ALA      5.6     0.2    -      -       -      -
     24D  VAL*     3.9    26.7    -      -       +      +
     27D  ILE*     3.3    36.6    -      -       +      -
    100D  PHE*     3.2    36.6    +      -       +      +
    101D  LEU*     3.5    14.8    -      -       +      +
    103D  ARG*     1.3    77.1    -      -       +      +
    105D  SER*     1.3    63.3    +      -       -      +
    106D  LEU      3.1     1.6    +      -       -      -
    107D  SER*     3.4    24.3    -      -       -      -
    108D  ARG*     4.5     1.9    +      -       -      +
    231D  GLU*     5.3     0.5    -      -       -      +
    233D  PHE*     3.7    33.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 105 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24D  VAL*     5.7     7.6    -      -       -      -
     28D  ARG*     4.8    13.7    -      -       -      -
    101D  LEU      3.5    10.6    +      -       -      -
    102D  ARG*     2.8    24.8    +      -       -      +
    104D  ILE*     1.3    80.7    -      -       -      +
    106D  LEU*     1.3    66.3    +      -       -      +
    108D  ARG*     4.9     5.8    +      -       -      +
    109D  ASN*     5.2     5.0    +      -       -      +
    136D  ARG*     5.5     5.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 106 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102D  ARG      4.0    14.1    -      -       -      +
    103D  ARG*     2.8    18.5    +      -       +      +
    105D  SER*     1.3    87.6    +      -       -      +
    107D  SER*     1.3    63.7    +      -       -      +
    108D  ARG      3.4     0.7    -      -       -      -
    109D  ASN*     2.9    21.9    +      -       +      +
    110D  LYS*     3.1    35.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 107 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103D  ARG      3.5     2.8    +      -       -      -
    104D  ILE*     3.4    25.4    +      -       -      -
    106D  LEU*     1.3    77.5    -      -       -      +
    108D  ARG*     1.3    65.9    +      -       -      +
    110D  LYS*     2.9    17.9    +      -       -      +
    111D  ILE*     3.1    15.3    +      -       -      +
    231D  GLU*     4.1    13.1    -      -       -      +
    232D  SER*     4.7     1.0    +      -       -      -
    233D  PHE*     5.1     1.6    -      -       -      -
    287D  ASP*     3.1    42.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 108 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19D  ASP*     2.5    37.5    +      -       -      +
     20D  MSE      3.9     2.0    -      -       -      +
     21D  ALA*     3.2    27.5    -      -       -      +
     24D  VAL*     5.9     0.6    -      -       -      +
    104D  ILE      4.5     2.8    +      -       -      +
    105D  SER      4.9     4.2    +      -       -      +
    106D  LEU      3.2     1.4    +      -       -      -
    107D  SER*     1.3    78.8    -      -       -      +
    109D  ASN*     1.3    62.3    +      -       -      +
    111D  ILE*     3.4    13.0    +      -       -      +
    112D  ALA*     3.2    19.6    +      -       -      +
    132D  ARG*     4.2    12.8    -      -       -      +
    133D  VAL*     4.0    30.7    -      -       +      +
    136D  ARG*     3.1    62.3    -      -       +      +
    137D  VAL*     5.8     0.5    -      -       -      +
    231D  GLU*     4.3    10.5    +      -       +      +
    504D  SO4      5.3     0.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 109 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105D  SER      5.4     0.4    +      -       -      -
    106D  LEU*     2.9    13.3    +      -       +      +
    108D  ARG*     1.3    74.8    -      -       -      +
    110D  LYS*     1.3    66.9    +      -       +      +
    112D  ALA*     3.2    12.1    +      -       -      +
    113D  ASP*     3.1    29.3    +      -       -      +
    136D  ARG*     2.5    40.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 110 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117B  THR*     4.7     6.1    -      -       +      +
    120B  LYS*     3.9    25.1    -      -       -      +
    146B  LYS*     5.8     5.8    -      -       -      +
    103D  ARG*     4.7     1.6    +      -       -      +
    106D  LEU*     3.1    50.6    +      -       -      +
    107D  SER*     2.9     9.1    +      -       -      +
    109D  ASN*     1.3    77.6    -      -       +      +
    111D  ILE*     1.3    62.4    +      -       -      +
    113D  ASP*     3.4     7.5    +      -       -      +
    114D  LEU*     3.0    31.9    +      -       +      +
    286D  THR      5.2     0.2    -      -       -      +
    287D  ASP*     3.9    35.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 111 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107D  SER      3.1    13.9    +      -       -      +
    108D  ARG*     3.5     8.7    -      -       -      +
    110D  LYS*     1.3    74.3    -      -       -      +
    112D  ALA*     1.3    66.9    +      -       -      +
    114D  LEU*     3.2     7.2    +      -       -      +
    115D  CYS*     2.9    24.6    +      -       -      +
    133D  VAL*     5.2     6.7    -      -       +      -
    137D  VAL*     4.1     6.7    -      -       +      -
    229D  VAL*     3.6    34.1    -      -       +      -
    230D  ALA*     3.4    37.5    -      -       -      +
    231D  GLU*     3.5    17.7    -      -       +      +
    285D  PHE*     3.6    16.4    -      -       +      +
    286D  THR      3.9    14.8    -      -       -      -
    287D  ASP*     4.2     2.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 112 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    108D  ARG      3.2     9.9    +      -       -      +
    109D  ASN*     3.2    22.0    +      -       -      +
    111D  ILE*     1.3    81.6    -      -       -      +
    113D  ASP*     1.3    63.3    +      -       -      +
    116D  HIS*     3.2    28.2    +      -       -      +
    136D  ARG*     3.8    16.8    -      -       +      +
    137D  VAL*     4.0    13.8    -      -       -      +
    140D  ALA*     3.8    21.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 113 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113B  ASP      4.8     1.2    -      -       -      +
    116B  HIS*     3.2    23.9    -      -       +      -
    117B  THR*     3.7    22.1    +      -       +      +
    144B  ALA*     4.7     8.7    -      -       -      +
    146B  LYS*     5.3     4.9    -      -       -      -
    109D  ASN*     3.1    15.2    +      -       -      +
    110D  LYS*     3.6     9.7    -      -       -      +
    111D  ILE      3.2     0.2    -      -       -      -
    112D  ALA*     1.3    78.6    -      -       -      +
    114D  LEU*     1.3    61.1    +      -       -      +
    116D  HIS*     3.0    28.7    +      -       -      -
    117D  THR*     3.4     7.6    +      -       -      -
    140D  ALA*     5.1     4.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 114 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117B  THR*     3.8    26.7    -      -       +      -
    118B  PHE*     4.9    14.6    -      -       +      -
    110D  LYS*     3.0    20.3    +      -       +      +
    111D  ILE*     3.7     3.8    -      -       -      +
    113D  ASP*     1.3    80.3    -      -       -      +
    115D  CYS*     1.3    62.6    +      -       -      +
    117D  THR*     3.6    14.8    -      -       -      -
    118D  PHE*     3.8    11.4    -      -       -      -
    285D  PHE*     3.9    11.9    -      -       +      -
    286D  THR      3.2    31.6    -      -       -      +
    287D  ASP*     5.2     2.0    -      -       -      +
    289D  GLY*     4.1    18.6    -      -       -      +
    290D  VAL*     3.9    17.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 115 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111D  ILE      2.9    17.2    +      -       -      +
    114D  LEU*     1.3    74.4    -      -       -      +
    116D  HIS*     1.3    52.4    +      -       -      +
    117D  THR      2.7    17.7    +      -       -      -
    118D  PHE*     2.7    22.3    +      -       -      +
    119D  ILE*     4.1     2.1    +      -       -      +
    137D  VAL*     3.8    16.8    -      -       +      -
    194D  ILE*     4.7    14.8    -      -       -      -
    227D  TYR*     5.0     6.1    -      -       -      -
    229D  VAL*     3.7    26.5    -      -       +      -
    285D  PHE*     3.5    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 116 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113B  ASP*     2.4    34.1    +      -       -      -
    116B  HIS*     5.1     3.8    -      -       -      -
    112D  ALA      3.2    17.9    +      -       -      +
    113D  ASP*     3.0    37.0    +      -       +      -
    115D  CYS*     1.3    76.0    -      -       -      +
    117D  THR*     1.3    67.7    +      -       -      +
    118D  PHE      3.1     0.2    -      -       -      -
    119D  ILE*     3.1    30.3    +      -       -      +
    137D  VAL*     3.9    19.3    -      -       -      +
    140D  ALA*     3.4    18.0    +      -       +      +
    141D  ALA*     4.1     8.5    -      -       +      +
    144D  ALA*     3.4    28.5    -      -       +      +
    146D  LYS*     3.8    12.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 117 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110B  LYS      5.4     0.7    -      -       -      +
    113B  ASP*     3.8    20.9    +      -       +      -
    114B  LEU*     3.1    41.8    -      -       +      +
    113D  ASP      3.4    14.7    +      -       -      -
    114D  LEU*     3.6    14.1    +      -       -      -
    115D  CYS      2.7     4.8    +      -       -      -
    116D  HIS*     1.3    84.9    +      -       -      +
    118D  PHE*     1.3    64.9    +      -       +      +
    119D  ILE      3.4     1.4    +      -       -      +
    146D  LYS*     4.5    10.5    +      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il