Contacts of the helix formed by residues 180 - 206 (chain I) in PDB entry 4PHZ


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 GLY 180 (chain I).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178I  HIS      3.2     1.8    +      -       -      -
    179I  TYR*     1.3    87.6    -      -       -      +
    181I  ILE*     1.3    62.5    +      -       -      +
    182I  SER*     3.2     4.0    -      -       -      +
    183I  ARG*     3.1    21.1    +      -       -      +
    184I  VAL*     3.1    13.5    +      -       -      +
    171J  ALA*     4.7     7.8    -      -       -      +
    172J  PHE*     3.8    19.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 181 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177I  GLU      3.7    21.3    -      -       -      +
    178I  HIS*     3.4    18.5    +      -       -      +
    179I  TYR      3.2     0.6    +      -       -      +
    180I  GLY*     1.3    76.0    -      -       -      +
    182I  SER*     1.3    61.2    +      -       -      +
    184I  VAL*     3.3     9.5    +      -       -      +
    185I  TYR*     3.3    49.8    +      -       +      +
    120J  PRO*     4.4     2.2    -      -       +      -
    121J  ILE*     4.0    20.4    -      -       +      +
    122J  SER*     3.7    42.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 182 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178I  HIS      4.7     2.2    +      -       -      -
    180I  GLY      3.2     1.7    +      -       -      +
    181I  ILE*     1.3    74.7    -      -       -      +
    183I  ARG*     1.3    61.7    +      -       -      +
    184I  VAL      3.2     0.2    +      -       -      -
    185I  TYR*     3.4    10.5    +      -       -      +
    186I  ALA*     2.8    30.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 183 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180I  GLY*     3.1    13.4    +      -       -      +
    182I  SER*     1.3    80.8    -      -       -      +
    184I  VAL*     1.3    62.3    +      -       +      +
    186I  ALA*     3.4     9.2    +      -       +      +
    187I  TRP*     3.1    22.5    +      -       -      +
    249I  VAL*     5.3     4.8    -      -       -      +
    250I  THR*     3.6    25.0    -      -       +      +
    253I  THR*     3.7    26.1    +      -       -      +
    254I  PHE*     3.5    33.6    -      -       -      -
    167J  PRO      3.9    21.2    -      -       -      +
    168J  ALA*     5.4     1.3    -      -       -      +
    171J  ALA*     4.4     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 184 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180I  GLY      3.1    14.6    +      -       -      +
    181I  ILE*     3.4    11.9    -      -       -      +
    182I  SER      3.1     0.4    -      -       -      -
    183I  ARG*     1.3    74.3    -      -       +      +
    185I  TYR*     1.4    53.4    -      -       +      +
    187I  TRP*     2.9     9.2    +      -       -      +
    188I  HIS*     2.8    37.0    +      -       +      +
    106J  TRP*     3.8    31.4    -      -       +      -
    121J  ILE*     4.8     4.5    -      -       +      +
    122J  SER*     5.6     0.4    -      -       -      -
    125J  PHE*     4.0    28.9    -      -       +      -
    168J  ALA*     4.0    26.0    -      -       +      +
    172J  PHE*     4.1    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 185 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181I  ILE*     3.3    35.1    +      -       +      +
    182I  SER*     3.5     9.2    -      -       -      +
    184I  VAL*     1.4    78.0    -      -       +      +
    186I  ALA*     1.3    58.3    +      -       -      +
    188I  HIS*     4.4     2.2    -      -       -      +
    189I  LEU*     2.9    56.3    +      -       +      +
    190I  PRO*     3.4     4.0    -      -       -      +
    106J  TRP*     3.7    33.2    -      +       -      -
    110J  TYR*     3.8    21.5    -      +       -      -
    121J  ILE*     3.4    24.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 186 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182I  SER      2.8    20.8    +      -       -      +
    183I  ARG*     3.5    11.2    -      -       +      +
    184I  VAL      3.2     0.2    -      -       -      -
    185I  TYR*     1.3    73.2    -      -       -      +
    187I  TRP*     1.3    60.3    +      -       -      +
    190I  PRO*     2.9    26.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 187 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183I  ARG      3.1    10.4    +      -       -      +
    184I  VAL      2.9     8.7    +      -       -      +
    186I  ALA*     1.3    79.3    -      -       -      +
    188I  HIS*     1.3    72.3    +      +       +      +
    190I  PRO*     3.7     3.3    -      -       +      +
    191I  TRP*     3.0    67.5    +      +       -      -
    242I  ALA*     3.8    21.5    -      -       +      -
    243I  THR*     4.6     8.5    -      -       -      -
    246I  GLY*     4.2    17.7    -      -       -      -
    128J  ALA*     4.8     4.5    -      -       +      +
    163J  PRO      5.2     0.2    -      -       -      -
    164J  ASN*     2.6    37.6    +      -       +      -
    167J  PRO*     3.7    40.1    -      -       +      +
    168J  ALA*     4.3    17.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 188 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184I  VAL*     2.8    28.3    +      -       +      +
    185I  TYR      4.4     0.2    -      -       -      +
    187I  TRP*     1.3    78.3    -      +       -      +
    189I  LEU*     1.3    72.8    +      -       +      +
    191I  TRP*     3.2     6.8    +      -       -      +
    192I  MET*     3.1    23.4    +      -       -      +
    102J  LEU*     4.5     6.0    -      -       +      +
    106J  TRP*     3.0    43.8    +      +       +      +
    125J  PHE*     4.5     3.0    -      +       -      -
    126J  PRO*     3.1    29.2    +      -       +      -
    127J  SER      3.9    14.6    -      -       -      -
    128J  ALA*     4.0    17.4    +      -       +      +
    165J  ASN*     5.0     1.0    +      -       -      -
    168J  ALA*     4.1    23.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 189 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185I  TYR*     2.9    46.5    +      -       +      +
    188I  HIS*     1.3    82.6    -      -       +      +
    190I  PRO*     1.4    70.0    -      -       +      +
    192I  MET*     3.1    21.2    +      -       +      +
    193I  ALA*     2.8    24.0    +      -       -      +
    106J  TRP*     4.9     9.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 190 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185I  TYR      3.4     5.4    -      -       -      +
    186I  ALA*     2.9    30.1    -      -       -      +
    187I  TRP*     3.7     4.9    -      -       +      +
    189I  LEU*     1.4    89.0    -      -       +      +
    191I  TRP*     1.3    55.5    +      -       +      +
    193I  ALA*     3.3     8.4    +      -       +      +
    194I  VAL*     2.7    40.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 191 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187I  TRP*     3.0    66.3    +      +       -      +
    188I  HIS*     3.2     8.4    +      -       -      +
    189I  LEU      3.2     1.0    -      -       -      -
    190I  PRO*     1.3    76.7    -      -       +      +
    192I  MET*     1.3    53.3    +      -       -      +
    194I  VAL*     3.0    26.5    +      -       +      +
    195I  GLY*     2.7    33.4    +      -       -      -
    239I  THR*     3.6    36.8    -      -       +      -
    242I  ALA*     4.0    28.7    -      -       +      -
    243I  THR*     4.4     5.6    -      -       -      -
    130J  ILE*     3.7    31.5    -      -       +      +
    131J  VAL*     3.6    23.5    -      -       +      +
    134J  ILE*     4.1     7.2    -      -       +      -
    164J  ASN*     5.7     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with MET 192 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188I  HIS*     3.1    16.5    +      -       +      +
    189I  LEU*     3.6    19.3    -      -       +      +
    191I  TRP*     1.3    73.7    -      -       -      +
    193I  ALA*     1.3    58.0    +      -       -      +
    195I  GLY*     3.1     1.0    +      -       -      -
    196I  ALA*     2.9    30.0    +      -       -      +
     99J  LEU*     3.7    21.3    -      -       +      +
    102J  LEU*     4.3     6.1    -      -       +      -
    103J  ILE*     3.4    45.3    -      -       +      +
    106J  TRP*     3.6    34.3    -      -       +      -
    130J  ILE*     3.9    12.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 193 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    189I  LEU      2.8    16.6    +      -       -      +
    190I  PRO*     3.4    12.6    -      -       +      +
    192I  MET*     1.3    72.4    -      -       -      +
    194I  VAL*     1.3    57.0    +      -       -      +
    195I  GLY      3.3     0.2    +      -       -      -
    196I  ALA*     3.3     6.0    +      -       -      +
    197I  ALA*     2.8    30.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 194 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    190I  PRO*     2.7    22.5    +      -       +      +
    191I  TRP*     3.0    35.0    +      -       +      +
    193I  ALA*     1.3    71.0    -      -       -      +
    195I  GLY*     1.3    63.3    +      -       -      +
    197I  ALA*     3.2     8.6    +      -       +      +
    198I  TRP*     3.1    24.0    +      -       +      +
    235I  VAL*     5.6     8.3    -      -       +      -
    239I  THR*     5.6     1.6    -      -       -      +
    134J  ILE*     4.4    13.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 195 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191I  TRP      2.7    16.7    +      -       -      -
    192I  MET*     3.1     4.9    +      -       -      -
    194I  VAL*     1.3    75.2    -      -       -      +
    196I  ALA*     1.3    62.6    +      -       -      +
    198I  TRP*     3.3     5.2    +      -       -      +
    199I  ILE*     3.2    24.6    +      -       -      +
     95J  VAL*     3.7    22.0    -      -       -      +
     99J  LEU*     4.1     6.1    -      -       -      -
    130J  ILE*     4.4    11.2    -      -       -      -
    134J  ILE*     5.6     1.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 196 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192I  MET      2.9    18.2    +      -       -      +
    193I  ALA*     3.7     7.2    -      -       -      +
    195I  GLY*     1.3    69.4    -      -       -      +
    197I  ALA*     1.3    66.1    +      -       -      +
    198I  TRP      3.3     0.2    +      -       -      -
    199I  ILE*     3.3     3.8    +      -       -      +
    200I  PHE*     2.8    46.1    +      -       +      -
     99J  LEU*     3.6    20.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 197 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    193I  ALA      2.8    17.2    +      -       -      +
    194I  VAL*     3.2    13.4    +      -       +      +
    196I  ALA*     1.3    72.9    -      -       -      +
    198I  TRP*     1.3    50.7    +      -       -      +
    200I  PHE*     3.0     5.4    +      -       -      +
    201I  PHE*     2.7    36.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 198 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    194I  VAL*     3.1    10.8    +      -       +      +
    195I  GLY*     3.5     8.5    -      -       -      +
    196I  ALA      3.3     0.2    -      -       -      -
    197I  ALA*     1.3    73.9    -      -       -      +
    199I  ILE*     1.3    63.1    +      -       -      +
    201I  PHE*     3.4     8.9    -      +       -      +
    202I  TRP*     2.8    74.5    +      +       -      -
    231I  ILE*     5.0     1.1    -      -       +      -
    232I  GLY*     4.1    10.3    -      -       -      -
    235I  VAL*     3.9    42.8    -      -       +      -
     91J  PRO*     3.2    32.8    +      -       +      -
     92J  PHE*     3.6    17.7    -      -       +      +
     95J  VAL*     4.1    26.9    -      -       +      +
    134J  ILE*     5.7     9.0    -      -       +      -
    137J  ASP*     4.4     6.2    +      -       +      +
    138J  VAL*     3.8    25.8    -      -       +      -
    141J  LEU*     4.1     4.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 199 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195I  GLY      3.2    10.3    +      -       -      +
    196I  ALA*     3.7     6.5    -      -       -      +
    198I  TRP*     1.3    76.8    -      -       -      +
    200I  PHE*     1.3    73.9    +      -       +      +
    202I  TRP      3.3     0.3    +      -       -      -
    203I  PHE*     3.0    20.7    +      -       +      +
     31J  LEU*     4.5    15.3    -      -       +      -
     35J  PHE*     4.8     5.4    -      -       +      -
     92J  PHE*     3.8    37.4    -      -       +      -
     95J  VAL*     4.1    10.8    -      -       +      +
     96J  PHE*     3.7    41.3    -      -       +      +
     99J  LEU*     4.1    24.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 200 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196I  ALA*     2.8    44.8    +      -       +      +
    197I  ALA*     3.5     7.2    -      -       -      +
    199I  ILE*     1.3    81.8    -      -       +      +
    201I  PHE*     1.3    69.9    +      -       -      +
    203I  PHE*     3.1    10.0    +      +       -      +
    204I  VAL*     3.0    29.3    +      -       +      +
     28J  TRP*     3.7    37.9    -      +       -      -
     31J  LEU*     5.0     7.2    -      -       +      -
     99J  LEU*     6.1     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 201 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197I  ALA      2.7    18.3    +      -       -      +
    198I  TRP*     3.4    15.0    -      +       -      +
    199I  ILE      3.3     0.2    -      -       -      -
    200I  PHE*     1.3    75.6    -      -       -      +
    202I  TRP*     1.3   105.5    +      +       -      +
    204I  VAL*     3.7     3.4    -      -       +      +
    205I  ARG*     3.0    73.6    +      -       +      +
    228I  ASP*     5.7     0.2    -      -       -      -
    231I  ILE*     3.8    27.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 202 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198I  TRP*     2.8    77.9    +      +       -      -
    201I  PHE*     1.3   102.2    -      +       -      +
    203I  PHE*     1.3    58.0    +      -       -      +
    204I  VAL      3.1     0.9    +      -       -      -
    205I  ARG*     4.6     1.1    -      -       +      +
    206I  LYS*     3.0    47.2    +      -       +      +
    224I  ILE*     3.7    18.4    -      -       +      -
    228I  ASP*     3.6    49.8    -      -       +      -
    231I  ILE*     4.4     6.1    -      -       +      -
    232I  GLY      4.9     0.2    -      -       -      -
     90J  LEU*     3.8     6.5    -      -       +      +
     91J  PRO*     3.7    28.9    -      -       +      -
     92J  PHE*     3.6    20.2    -      +       +      -
    141J  LEU*     4.3     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 203 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199I  ILE      3.0    17.8    +      -       -      +
    200I  PHE*     3.1     8.9    +      +       -      +
    202I  TRP*     1.3    76.6    -      -       -      +
    204I  VAL*     1.3    67.3    +      -       +      +
    206I  LYS      2.7    15.0    -      -       -      +
    207I  GLY*     4.1     4.6    -      -       -      -
    208I  ILE*     3.5    31.6    -      -       +      -
     24J  GLN*     4.2     8.5    -      -       -      -
     27J  ASP*     3.5    45.2    -      -       +      +
     28J  TRP*     3.6    45.5    -      +       -      -
     31J  LEU*     3.8    22.7    -      -       +      -
     90J  LEU*     5.1     2.7    -      -       -      -
     92J  PHE*     4.1    11.6    -      +       +      -
----------------------------------------------------------
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Residues in contact with VAL 204 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200I  PHE*     3.0    20.5    +      -       +      +
    201I  PHE*     3.7     3.6    -      -       +      +
    203I  PHE*     1.3    90.8    -      -       +      +
    205I  ARG*     1.3    66.1    +      -       +      +
    206I  LYS      2.7    22.0    +      -       -      +
    207I  GLY*     4.9     0.7    -      -       -      -
     24J  GLN*     6.4     0.2    -      -       -      +
     28J  TRP*     5.5     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 205 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201I  PHE*     3.0    60.4    +      -       +      +
    202I  TRP*     4.5     2.0    -      -       -      +
    204I  VAL*     1.3    83.9    -      -       +      +
    206I  LYS*     1.3    83.0    +      -       +      +
    231I  ILE*     4.7     8.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 206 (chain I). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202I  TRP*     3.0    29.7    +      -       +      +
    203I  PHE      2.7    20.3    -      -       -      +
    204I  VAL      2.7     4.7    +      -       -      +
    205I  ARG*     1.3    99.6    -      -       +      +
    207I  GLY*     1.3    63.7    +      -       -      +
    210I  THR*     5.9     1.6    -      -       -      -
    211I  SER*     3.3    17.0    -      -       -      +
    214I  ARG*     5.3     8.3    -      -       -      +
    222I  ASP      5.1     2.2    +      -       -      +
    223I  VAL*     2.7    38.7    +      -       +      +
    224I  ILE*     4.0     5.1    -      -       +      +
    228I  ASP*     2.6    34.7    +      -       -      -
     90J  LEU*     4.0    12.3    -      -       +      -
----------------------------------------------------------
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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