Contacts of the helix formed by residues 172 - 201 (chain Q) in PDB entry 5IYB


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 ASP 172 (chain Q).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169Q  PRO*     5.8     0.6    -      -       -      +
    171Q  LYS*     1.3    75.2    -      -       +      +
    173Q  ALA*     1.3    54.8    +      -       -      +
    174Q  ARG      3.6     1.3    -      -       -      -
    175Q  THR*     3.0    18.8    +      -       -      -
    176Q  LEU*     2.4    63.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 173 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169Q  PRO*     5.1     8.6    -      -       +      +
    170Q  LYS      6.0     0.4    -      -       -      +
    171Q  LYS      2.7    15.8    +      -       -      +
    172Q  ASP*     1.3    78.8    -      -       -      +
    174Q  ARG*     1.3    62.4    +      -       +      +
    176Q  LEU*     3.5     2.9    +      -       -      +
    177Q  LEU*     3.2    34.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 174 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117Q  ASP*     2.3    50.4    +      -       -      +
    119Q  ARG      5.5     0.6    +      -       -      -
    121Q  SER*     5.6     6.1    +      -       -      -
    122Q  THR*     5.2     2.0    -      -       -      +
    169Q  PRO*     3.5    41.1    -      -       +      +
    172Q  ASP      3.6     0.2    -      -       -      -
    173Q  ALA*     1.3    76.6    -      -       +      +
    175Q  THR*     1.3    59.1    +      -       -      +
    177Q  LEU*     3.2    33.5    +      -       -      +
    178Q  ALA*     2.9    25.1    +      -       -      +
    221R  ARG*     4.8    13.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 175 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169Q  PRO*     6.0     1.0    -      -       -      +
    172Q  ASP*     3.0    22.0    +      -       -      -
    174Q  ARG*     1.3    76.2    +      -       -      +
    176Q  LEU*     1.3    53.8    +      -       -      +
    178Q  ALA*     3.1    10.8    +      -       +      +
    179Q  ARG*     2.6    56.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 176 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    172Q  ASP*     2.4    52.7    +      -       -      +
    173Q  ALA*     3.7     6.3    -      -       -      +
    175Q  THR*     1.3    68.3    -      -       -      +
    177Q  LEU*     1.3    68.0    +      -       +      +
    179Q  ARG*     3.5    11.6    -      -       +      -
    180Q  PHE*     2.6    42.6    +      -       +      +
    183Q  GLN*     5.8     6.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 177 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117Q  ASP*     5.1     5.8    -      -       -      +
    173Q  ALA*     3.2    20.6    +      -       +      +
    174Q  ARG*     3.2    45.1    +      -       -      +
    176Q  LEU*     1.3    88.8    -      -       +      +
    178Q  ALA*     1.3    57.1    +      -       -      +
    180Q  PHE*     3.2    12.7    -      -       +      +
    181Q  ASN*     2.7    32.6    +      -       -      +
    213R  ASP*     5.2     9.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 178 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117Q  ASP*     5.8     0.8    +      -       -      -
    118Q  GLU*     5.8     9.0    -      -       -      +
    174Q  ARG      2.9    13.1    +      -       -      +
    175Q  THR*     3.1    14.8    +      -       +      +
    177Q  LEU*     1.3    75.9    -      -       -      +
    179Q  ARG*     1.3    58.2    +      -       +      +
    181Q  ASN*     3.2    10.4    +      -       -      +
    182Q  GLU*     2.9    34.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 179 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    175Q  THR*     2.6    38.6    +      -       +      +
    176Q  LEU*     3.6    15.9    -      -       +      +
    178Q  ALA*     1.3    72.3    -      -       +      +
    180Q  PHE*     1.3    53.1    +      -       -      +
    182Q  GLU*     2.8    38.4    +      -       -      +
    183Q  GLN*     2.7    45.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 180 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176Q  LEU*     2.6    29.3    +      -       +      +
    177Q  LEU*     3.2    15.3    -      -       +      +
    179Q  ARG*     1.3    71.8    -      -       -      +
    181Q  ASN*     1.3    59.3    +      -       -      +
    183Q  GLN*     3.0    24.7    +      -       +      +
    184Q  ILE*     2.8    49.7    +      -       +      +
    210R  PHE      4.7     1.8    -      -       -      -
    211R  SER*     1.9    57.0    -      -       -      -
    212R  VAL*     3.4    17.0    -      -       +      -
    213R  ASP*     3.8    13.0    -      -       -      -
    218R  LYS*     3.9    13.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 181 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114Q  ILE*     3.2    41.2    +      -       -      +
    118Q  GLU*     4.2    23.6    +      -       -      +
    177Q  LEU      2.7    16.8    +      -       -      +
    178Q  ALA*     3.3    13.3    +      -       -      +
    180Q  PHE*     1.3    74.6    -      -       -      +
    182Q  GLU*     1.3    63.5    +      -       -      +
    184Q  ILE*     3.3    11.9    +      -       -      +
    185Q  GLU*     3.1    23.3    +      -       -      +
    218R  LYS*     6.3     0.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 182 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178Q  ALA*     2.9    20.9    +      -       -      +
    179Q  ARG*     2.8    52.0    +      -       -      +
    181Q  ASN*     1.3    78.6    -      -       +      +
    183Q  GLN*     1.3    54.4    +      -       +      +
    185Q  GLU*     3.4    15.4    +      -       -      +
    186Q  PRO*     2.9    27.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 183 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176Q  LEU*     5.8     5.6    -      -       -      +
    179Q  ARG*     2.7    25.8    +      -       +      +
    180Q  PHE*     3.0    28.9    +      -       +      +
    182Q  GLU*     1.3    73.6    -      -       +      +
    184Q  ILE*     1.3    63.2    +      -       +      +
    186Q  PRO*     3.3    13.4    -      -       -      +
    187Q  ILE*     4.1     8.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 184 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20Q  TYR*     5.4     5.2    -      -       -      +
    114Q  ILE*     5.5     8.7    -      -       +      -
    180Q  PHE*     2.8    35.4    +      -       +      +
    181Q  ASN*     3.5    17.5    -      -       -      +
    183Q  GLN*     1.3    76.4    -      -       +      +
    185Q  GLU*     1.3    58.6    +      -       -      +
    187Q  ILE*     3.1    19.5    +      -       +      +
    188Q  TYR*     2.9    35.8    +      -       +      +
    210R  PHE*     3.5    38.1    -      -       +      +
    211R  SER*     3.9    11.7    -      -       -      +
    218R  LYS*     5.7     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 185 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181Q  ASN*     3.1    12.5    +      -       -      +
    182Q  GLU*     3.6    17.0    -      -       -      +
    184Q  ILE*     1.3    74.4    -      -       -      +
    186Q  PRO*     1.3    65.3    -      -       +      +
    188Q  TYR*     3.3    10.3    +      -       +      +
    189Q  ALA*     2.8    26.3    +      -       -      +
    192Q  ARG*     4.1    22.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 186 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182Q  GLU      2.9    27.8    -      -       -      +
    183Q  GLN*     3.3    12.1    -      -       -      +
    185Q  GLU*     1.3    78.6    -      -       +      +
    187Q  ILE*     1.3    56.7    +      -       -      +
    188Q  TYR      2.9     5.4    -      -       -      -
    189Q  ALA*     2.9    28.2    +      -       +      +
    190Q  LEU*     4.0     3.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 187 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20Q  TYR*     5.1    12.6    -      -       +      +
    183Q  GLN      4.1     6.0    +      -       -      +
    184Q  ILE*     3.1    33.3    +      -       +      +
    186Q  PRO*     1.3    79.4    -      -       -      +
    188Q  TYR*     1.3    57.6    +      -       +      +
    190Q  LEU*     4.7     3.9    +      -       -      +
    191Q  LEU*     3.2    22.2    -      -       -      +
    210R  PHE*     5.9     2.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 188 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20Q  TYR*     5.2     6.7    -      +       -      +
    107Q  LEU*     4.3    18.4    -      -       +      +
    111Q  ARG*     2.2    50.9    +      -       +      +
    184Q  ILE*     2.9    25.3    +      -       +      +
    185Q  GLU*     3.6    10.3    -      -       +      +
    186Q  PRO      2.9     0.2    -      -       -      -
    187Q  ILE*     1.3    78.6    -      -       +      +
    189Q  ALA*     1.3    52.4    +      -       -      +
    190Q  LEU      3.3     2.0    -      -       -      -
    191Q  LEU*     3.1    33.2    +      -       +      +
    192Q  ARG*     2.7    60.2    +      -       +      -
    195Q  GLU*     2.9    10.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 189 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185Q  GLU      2.8     9.9    +      -       -      +
    186Q  PRO*     2.9    18.3    +      -       +      +
    188Q  TYR*     1.3    76.7    -      -       -      +
    190Q  LEU*     1.3    51.3    -      -       -      +
    192Q  ARG*     3.1    31.1    +      -       -      +
    193Q  GLU*     2.8    33.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 190 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186Q  PRO      4.0     3.7    +      -       -      +
    187Q  ILE*     4.9     2.7    -      -       -      +
    188Q  TYR      3.3     0.2    -      -       -      -
    189Q  ALA*     1.3    79.0    -      -       -      +
    191Q  LEU*     1.3    62.5    +      -       +      +
    193Q  GLU*     3.2    27.1    +      -       -      +
    194Q  THR*     2.7    40.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 191 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17Q  LEU*     4.0    19.1    -      -       +      +
     20Q  TYR*     3.5    52.5    -      -       +      +
    107Q  LEU*     6.1     0.7    -      -       +      -
    187Q  ILE      3.2    20.9    -      -       -      +
    188Q  TYR*     3.1    33.4    +      -       +      +
    190Q  LEU*     1.3    86.4    -      -       +      +
    192Q  ARG*     1.3    54.7    +      -       -      +
    194Q  THR*     3.2    12.3    -      -       -      +
    195Q  GLU*     2.8    38.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 192 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185Q  GLU*     4.1    24.5    +      -       -      +
    188Q  TYR*     2.7    40.6    +      -       +      +
    189Q  ALA*     3.2    33.9    +      -       -      +
    191Q  LEU*     1.3    72.2    -      -       -      +
    193Q  GLU*     1.3    56.7    +      -       -      +
    195Q  GLU*     3.2    19.0    -      -       -      +
    196Q  ASP*     2.8    25.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 193 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    189Q  ALA      2.8    12.6    +      -       -      +
    190Q  LEU*     3.2    27.6    +      -       +      +
    192Q  ARG*     1.3    72.8    -      -       -      +
    194Q  THR*     1.3    54.1    +      -       -      +
    195Q  GLU      3.1     1.1    -      -       -      -
    196Q  ASP*     3.1    13.3    +      -       +      +
    197Q  VAL*     2.8    44.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 194 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13Q  ALA*     3.9    31.2    -      -       +      +
     17Q  LEU*     4.0    18.0    -      -       +      +
    190Q  LEU*     2.7    32.6    +      -       -      +
    191Q  LEU*     3.2    15.7    -      -       -      +
    193Q  GLU*     1.3    70.8    -      -       -      +
    195Q  GLU*     1.3    54.9    +      -       -      +
    197Q  VAL*     3.6     7.2    +      -       -      +
    198Q  ASN*     2.7    47.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 195 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17Q  LEU*     4.5     7.6    -      -       +      -
    104Q  LYS*     5.5    12.8    +      -       +      +
    107Q  LEU*     3.2    24.7    -      -       +      +
    111Q  ARG*     2.6    40.7    +      -       -      -
    188Q  TYR*     2.9    10.8    +      -       -      -
    191Q  LEU*     2.8    19.1    +      -       -      +
    192Q  ARG*     3.2    19.2    -      -       -      +
    193Q  GLU      3.1     0.2    -      -       -      -
    194Q  THR*     1.3    71.7    -      -       -      +
    196Q  ASP*     1.3    53.9    +      -       -      +
    198Q  ASN*     3.1     9.3    +      -       -      +
    199Q  LEU*     2.5    39.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 196 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192Q  ARG      2.8    17.2    +      -       -      +
    193Q  GLU*     3.2    17.3    -      -       +      +
    195Q  GLU*     1.3    72.0    -      -       -      +
    197Q  VAL*     1.3    57.5    +      -       +      +
    199Q  LEU*     3.3    16.5    +      -       -      +
    200Q  ALA*     2.9    28.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 197 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13Q  ALA*     5.2    12.3    -      -       +      -
    193Q  GLU*     2.8    31.9    +      -       +      +
    194Q  THR*     3.8     7.6    -      -       -      +
    196Q  ASP*     1.3    69.5    -      -       +      +
    198Q  ASN*     1.3    57.7    +      -       -      +
    200Q  ALA*     3.3     6.9    +      -       -      +
    201Q  TYR*     2.7    39.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 198 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11Q  PRO*     5.8     1.8    -      -       -      +
     13Q  ALA*     4.6     6.2    -      -       -      +
     14Q  LEU*     4.0    36.5    -      -       -      +
     17Q  LEU*     3.9    12.6    -      -       -      +
    102Q  VAL*     4.9     6.7    -      -       +      -
    194Q  THR*     2.7    40.8    +      -       -      +
    195Q  GLU*     3.3     7.4    +      -       -      +
    197Q  VAL*     1.3    77.3    -      -       -      +
    199Q  LEU*     1.3    58.3    -      -       -      +
    201Q  TYR*     3.0    34.1    +      -       -      +
    202Q  GLU*     3.2    20.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 199 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    104Q  LYS*     5.3    14.6    -      -       +      +
    195Q  GLU      2.5    20.7    +      -       -      +
    196Q  ASP*     3.3    17.5    +      -       -      +
    198Q  ASN*     1.3    70.3    -      -       -      +
    200Q  ALA*     1.3    63.8    +      -       -      +
    202Q  GLU*     3.4    34.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 200 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196Q  ASP      2.9    16.3    +      -       -      +
    197Q  VAL*     3.7     7.2    -      -       -      +
    199Q  LEU*     1.3    72.3    -      -       -      +
    201Q  TYR*     1.3    57.6    +      -       -      +
    202Q  GLU      3.0    11.1    +      -       -      -
    203Q  ILE*     3.1    23.0    +      -       -      +
    204Q  LEU*     6.1     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 201 (chain Q). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11Q  PRO*     3.5    45.0    -      -       +      +
     14Q  LEU*     6.3     2.0    -      -       +      -
    197Q  VAL*     2.7    22.9    +      -       +      +
    198Q  ASN*     3.0    29.6    -      -       -      +
    200Q  ALA*     1.3    71.1    -      -       -      +
    202Q  GLU*     1.3    56.9    +      -       -      +
    203Q  ILE      3.1     2.2    -      -       -      -
    204Q  LEU*     2.9    64.9    +      -       +      +
----------------------------------------------------------
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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