Contacts of the helix formed by residues 114 - 138 (chain M) in PDB entry 1YST


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 LEU 114 (chain M).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70M  ILE*     5.0    15.0    -      -       +      -
     73M  TRP*     3.3    61.9    -      -       +      +
     94M  LEU*     2.9    54.1    -      -       +      +
     95M  GLU      4.2     6.5    -      -       -      +
     96M  PRO*     5.7     0.2    -      -       +      -
    112M  GLY      3.2     9.7    +      -       -      +
    113M  GLY*     1.3    68.5    -      -       -      +
    115M  TRP*     1.2    95.5    +      -       +      +
    117M  ILE*     3.2     7.1    +      -       -      +
    118M  ALA*     3.1    20.5    +      -       +      +
    177M  TYR*     4.2    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 115 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96M  PRO*     3.7    28.0    -      -       +      +
     97M  PRO*     4.3     6.7    -      -       +      -
    113M  GLY      2.7     5.0    +      -       -      +
    114M  LEU*     1.2    92.0    -      -       +      +
    116M  LEU*     1.3    70.8    +      -       +      +
    119M  SER*     2.6    53.4    +      -       -      +
    161M  GLY      3.1    26.9    -      -       -      -
    171M  TRP*     3.9    30.1    -      +       +      -
    174M  ALA*     3.1    39.5    -      -       +      +
    176M  PRO*     3.6    20.2    -      -       +      +
    177M  TYR*     3.5    29.5    -      +       -      -
    310M  SPO      4.0    25.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 116 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97M  PRO*     5.3     4.9    -      -       +      -
    104M  SER      4.7     1.3    -      -       -      +
    105M  PHE*     3.4    63.5    -      -       +      +
    107M  ALA*     3.8    26.0    -      -       +      +
    113M  GLY*     2.9    16.2    +      -       -      +
    115M  TRP*     1.3    75.4    -      -       +      +
    117M  ILE*     1.3    66.9    +      -       +      +
    119M  SER*     4.0     3.3    -      -       -      -
    120M  PHE*     2.9    26.9    +      -       -      +
    171M  TRP*     3.8    27.4    -      -       +      +
    310M  SPO      4.5     6.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 117 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65M  MET*     4.7     6.3    -      -       +      -
     69M  THR*     4.8     7.4    -      -       +      -
     73M  TRP*     3.6    24.0    -      -       +      -
    113M  GLY*     3.5    16.6    -      -       -      +
    114M  LEU      3.2    12.8    +      -       -      +
    115M  TRP      2.9     2.6    +      -       -      -
    116M  LEU*     1.3    76.8    -      -       +      +
    118M  ALA*     1.3    66.3    +      -       -      +
    120M  PHE*     2.9    21.8    +      -       -      +
    121M  PHE*     3.3    28.3    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 118 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65M  MET*     4.5    11.4    -      -       -      -
     66M  TRP*     3.3    18.4    -      -       +      -
     69M  THR*     4.6    14.3    -      -       +      +
     70M  ILE*     4.6     8.3    -      -       +      -
     73M  TRP*     5.3     0.2    -      -       +      -
    114M  LEU*     3.1    16.7    +      -       +      +
    115M  TRP      3.0     4.6    +      -       -      +
    117M  ILE*     1.3    76.1    -      -       -      +
    119M  SER*     1.3    64.4    +      -       -      +
    120M  PHE      2.9     1.4    +      -       -      -
    121M  PHE*     2.9    13.5    +      -       -      +
    122M  MET      3.1     9.9    +      -       -      -
    177M  TYR*     3.9    20.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 119 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115M  TRP*     2.6    50.7    +      -       -      -
    118M  ALA*     1.3    73.8    -      -       -      +
    120M  PHE*     1.3    58.9    +      -       -      -
    122M  MET*     3.9     3.1    -      -       -      -
    123M  PHE*     3.0    24.8    +      -       -      +
    177M  TYR*     2.5    27.5    +      -       -      -
    310M  SPO      3.4    32.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 120 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    116M  LEU      2.9    16.7    +      -       -      +
    117M  ILE*     2.9    10.9    +      -       -      +
    118M  ALA      2.9     0.2    +      -       -      -
    119M  SER*     1.3    77.0    -      -       -      +
    121M  PHE*     1.3   101.9    +      +       -      +
    123M  PHE*     3.1    24.4    +      +       -      +
    124M  VAL*     3.2    24.9    +      -       +      +
    310M  SPO      4.0    38.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 121 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61M  PHE*     5.9     9.0    -      +       -      -
     62M  SER*     3.9    24.9    -      -       -      +
     65M  MET*     2.8    51.8    -      -       +      -
     66M  TRP*     4.6     2.2    -      -       +      -
    117M  ILE*     3.3    22.8    +      -       +      -
    118M  ALA      2.9     5.3    +      -       -      +
    120M  PHE*     1.3   104.1    -      +       -      +
    122M  MET*     1.3    60.8    +      -       -      +
    124M  VAL*     2.9     9.9    +      -       +      +
    125M  ALA*     2.8    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 122 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66M  TRP*     3.3    63.7    -      -       +      +
    118M  ALA      3.1     8.2    +      -       -      +
    119M  SER*     4.1     4.9    -      -       -      +
    121M  PHE*     1.3    77.3    -      -       -      +
    123M  PHE*     1.3    63.7    +      -       -      +
    124M  VAL      3.3     0.2    +      -       -      -
    125M  ALA*     4.2     7.0    -      -       +      -
    126M  VAL*     3.5    15.9    +      -       -      +
    157M  TRP*     2.9    49.2    -      -       +      -
    177M  TYR*     4.1     0.7    -      -       -      -
    307M  BCL      4.7     9.9    -      -       +      +
    308M  BCL      3.8    33.9    -      -       +      -
    310M  SPO      3.9    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 123 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119M  SER      3.0    16.5    +      -       -      +
    120M  PHE*     3.2    18.2    -      +       -      +
    121M  PHE      3.0     0.2    -      -       -      -
    122M  MET*     1.3    79.2    -      -       -      +
    124M  VAL*     1.3    67.2    +      -       +      +
    126M  VAL*     4.8     0.5    -      -       -      +
    127M  TRP*     3.3    54.9    +      +       +      +
    157M  TRP*     4.2     9.8    -      -       -      -
    158M  MET*     3.7    25.8    -      -       +      -
    162M  PHE*     5.2     3.1    -      +       -      -
    310M  SPO      3.6    59.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 124 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58M  LEU*     5.1    14.4    -      -       +      -
     62M  SER*     4.6     7.6    -      -       -      +
    120M  PHE*     3.2    39.0    +      -       +      +
    121M  PHE*     2.9    16.0    +      -       +      +
    123M  PHE*     1.3    79.1    -      -       +      +
    125M  ALA*     1.3    68.1    +      -       -      +
    127M  TRP*     2.7    19.4    +      -       +      -
    128M  SER*     2.6    26.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 125 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59M  SER*     3.6     9.8    +      -       -      +
     62M  SER*     3.9     7.2    +      -       -      -
     63M  GLY*     4.0    29.4    -      -       -      +
    121M  PHE      2.8    18.4    +      -       -      +
    122M  MET*     3.9     9.4    -      -       +      +
    124M  VAL*     1.3    71.3    -      -       -      +
    126M  VAL*     1.3    61.7    +      -       +      +
    128M  SER*     3.0     8.2    +      -       -      -
    129M  TRP*     2.8    27.4    +      -       -      +
    308M  BCL      5.2     4.5    -      -       +      -
    309M  BPH      4.1    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 126 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122M  MET      3.5    14.0    +      -       -      +
    123M  PHE      4.8     0.2    -      -       -      +
    124M  VAL      3.0     1.8    +      -       -      -
    125M  ALA*     1.3    73.1    -      -       -      +
    127M  TRP*     1.3    51.9    +      -       -      +
    129M  TRP*     2.8     4.0    +      -       -      +
    130M  TRP*     2.7    33.3    +      -       -      +
    150M  PHE*     3.3    30.8    -      -       +      -
    154M  ILE*     3.5    21.3    -      -       +      -
    157M  TRP*     4.4    13.9    -      -       +      +
    308M  BCL      3.6    49.6    -      -       +      -
    309M  BPH      3.6    11.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 127 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123M  PHE*     3.3    49.5    +      +       +      +
    124M  VAL*     2.7    16.3    +      -       +      +
    126M  VAL*     1.3    76.4    -      -       -      +
    128M  SER*     1.3    55.6    +      -       -      +
    130M  TRP*     3.2    40.7    +      +       +      +
    131M  GLY*     3.1    19.8    +      -       -      -
    151M  LEU*     4.5    18.2    -      -       +      -
    154M  ILE*     3.1    35.7    -      -       +      +
    157M  TRP*     5.0     2.0    -      -       -      -
    158M  MET*     3.9    18.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 128 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55M  LEU*     4.0    14.3    -      -       -      +
     58M  LEU*     4.1    24.3    -      -       -      +
     59M  SER*     3.2    20.5    +      -       -      -
    124M  VAL*     2.6    39.3    +      -       -      +
    125M  ALA*     3.0     9.5    +      -       -      -
    127M  TRP*     1.3    72.9    -      -       -      +
    129M  TRP*     1.3    57.1    +      -       -      +
    130M  TRP      3.2     0.2    -      -       -      -
    131M  GLY*     3.1    13.9    +      -       -      +
    132M  ARG*     3.3    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 129 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219L  LEU*     4.2    16.7    -      -       +      +
    220L  VAL*     5.6     2.9    -      -       +      -
     56M  GLY*     5.0     2.9    -      -       -      -
     59M  SER*     3.5    24.2    +      -       -      -
     60M  LEU*     5.1    12.6    -      -       +      -
    125M  ALA      2.8     6.0    +      -       -      +
    126M  VAL      2.8     7.9    +      -       -      +
    128M  SER*     1.3    74.1    -      -       -      +
    130M  TRP*     1.3    61.8    +      -       -      +
    131M  GLY      3.0     0.9    -      -       -      -
    132M  ARG*     3.5    55.3    +      -       +      +
    133M  THR*     2.8    18.4    +      -       -      -
    150M  PHE*     5.0     4.3    -      +       +      -
    309M  BPH      2.9    89.7    +      +       +      +
----------------------------------------------------------
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Residues in contact with TRP 130 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126M  VAL      2.7    11.3    +      -       -      +
    127M  TRP*     3.2    43.3    -      +       +      +
    129M  TRP*     1.3    76.4    -      -       -      +
    131M  GLY*     1.3    75.6    +      -       -      +
    133M  THR*     2.9    16.7    +      -       -      -
    134M  TYR*     3.5    38.7    +      +       +      +
    147M  ALA*     3.7    25.6    +      -       +      +
    148M  TRP*     3.6    28.7    -      +       -      -
    150M  PHE*     3.6    29.6    -      +       +      -
    151M  LEU*     4.1    22.3    -      -       +      +
    154M  ILE*     4.9     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 131 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55M  LEU*     3.7    17.0    -      -       -      -
    127M  TRP      3.1    12.3    +      -       -      -
    128M  SER*     3.1     7.8    +      -       -      -
    129M  TRP      3.0     1.0    -      -       -      -
    130M  TRP*     1.3    89.8    -      -       -      +
    132M  ARG*     1.3    67.9    +      -       -      +
    134M  TYR*     3.0    14.9    +      -       -      +
    135M  LEU*     3.5     7.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 132 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    218L  ASP      4.3     4.6    +      -       -      -
    219L  LEU*     2.9    55.4    +      -       +      +
     50M  ILE*     5.8     2.4    -      -       -      +
     51M  TYR      3.8    25.2    +      -       -      +
     52M  LEU*     4.8    11.5    -      -       -      +
     53M  GLY      5.0     1.0    -      -       -      +
     55M  LEU*     3.7    16.7    -      -       +      +
     56M  GLY*     3.9    26.7    -      -       -      -
    128M  SER      3.3     8.8    +      -       -      +
    129M  TRP*     3.5    54.2    -      -       -      +
    131M  GLY*     1.3    73.1    -      -       -      +
    133M  THR*     1.3    54.1    +      -       -      +
    134M  TYR      2.6    14.0    +      -       -      -
    135M  LEU*     2.9     2.9    +      -       -      +
    136M  ARG*     2.8    35.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 133 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215L  PHE*     4.3     4.1    -      -       +      -
    219L  LEU*     4.2    23.1    -      -       +      +
    129M  TRP*     2.8    21.5    +      -       -      -
    130M  TRP*     2.9    13.7    +      -       -      -
    132M  ARG*     1.3    72.2    -      -       -      +
    134M  TYR*     1.3    55.1    +      -       -      +
    136M  ARG*     4.7     2.0    -      -       -      -
    137M  ALA*     3.1    24.2    +      -       -      +
    146M  THR*     3.9    36.7    -      -       -      +
    147M  ALA*     3.9    17.4    -      -       -      +
    150M  PHE*     5.4     3.8    -      -       +      -
    309M  BPH      4.2    13.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 134 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201L  GLU*     5.1     3.8    -      -       -      -
    130M  TRP*     3.5    39.3    -      +       +      +
    131M  GLY      3.0     9.3    +      -       -      +
    132M  ARG      2.6     7.3    +      -       -      -
    133M  THR*     1.3    73.2    -      -       -      +
    135M  LEU*     1.3    74.0    +      -       +      +
    136M  ARG      3.2     0.7    -      -       -      -
    137M  ALA*     3.0     5.3    +      -       +      +
    138M  GLN*     2.8    37.8    +      -       +      +
    143M  GLY      5.5     0.9    -      -       -      -
    144M  LYS*     3.4    45.2    -      -       +      +
    147M  ALA*     4.5     9.0    -      -       +      -
    148M  TRP*     4.9    11.1    -      +       -      -
----------------------------------------------------------
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Residues in contact with LEU 135 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55M  LEU*     3.5    44.0    -      -       +      -
    131M  GLY*     3.5    11.6    +      -       -      +
    132M  ARG*     2.9     3.4    +      -       -      +
    134M  TYR*     1.3    87.0    -      -       +      +
    136M  ARG*     1.3    72.1    +      -       -      +
    138M  GLN*     3.1    23.0    +      -       -      +
    139M  ALA*     3.0    30.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 136 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215L  PHE*     3.9    23.8    -      -       +      -
    218L  ASP*     3.5    50.5    +      -       +      +
    219L  LEU*     4.6     8.7    -      -       +      -
     24M  VAL*     4.8     2.6    -      -       -      +
     25M  ASN      5.5     0.2    -      -       -      +
     51M  TYR*     3.3    44.7    +      -       -      -
     53M  GLY*     6.1     0.4    -      -       -      -
     55M  LEU*     5.8     5.7    -      -       -      +
    132M  ARG*     2.8    25.8    +      -       +      +
    135M  LEU*     1.3    93.3    +      -       -      +
    137M  ALA*     1.3    59.6    +      -       -      +
    139M  ALA*     3.8    30.6    -      -       -      +
    140M  MET*     4.2    10.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 137 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215L  PHE*     4.2     7.2    -      -       +      -
    133M  THR      3.1    21.4    +      -       -      +
    134M  TYR*     3.0     9.4    +      -       +      +
    136M  ARG*     1.3    78.6    -      -       -      +
    138M  GLN*     1.3    58.7    +      -       -      +
    139M  ALA      3.4     0.4    +      -       -      -
    140M  MET      3.7     0.7    +      -       -      -
    141M  GLY      2.5    35.6    +      -       -      +
    142M  MET*     3.5    31.5    -      -       +      +
    143M  GLY      4.4     5.6    -      -       -      +
    144M  LYS*     4.8     5.2    -      -       -      +
    146M  THR*     4.6     5.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 138 (chain M). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201L  GLU*     4.9    19.0    +      -       +      +
     23M  ASP*     5.0     4.2    -      -       -      +
    134M  TYR*     2.8    28.7    +      -       +      +
    135M  LEU*     3.4    25.3    -      -       -      +
    137M  ALA*     1.3    74.1    -      -       -      +
    139M  ALA*     1.3    55.9    +      -       -      +
    140M  MET*     2.9    16.5    +      -       -      -
    141M  GLY*     4.2     4.1    +      -       -      -
    143M  GLY      5.6     1.1    -      -       -      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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

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