Contacts of the helix formed by residues 200 - 225 (chain A) in PDB entry 3KSY


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 THR 200 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198A  GLU*     3.9    15.8    -      -       +      +
    199A  GLN*     1.3    78.1    -      -       -      +
    201A  TYR*     1.3    63.6    +      -       -      +
    202A  TYR*     4.3     4.6    -      -       -      +
    203A  ASP*     3.0    30.1    +      -       -      +
    204A  LEU*     3.4    20.5    +      -       -      +
    363A  LYS*     5.2     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 201 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199A  GLN      3.8     1.2    +      -       -      -
    200A  THR*     1.3    73.7    -      -       -      +
    202A  TYR*     1.3    59.2    +      -       -      +
    204A  LEU*     3.1    27.8    -      -       +      +
    205A  VAL*     3.4    12.2    -      -       +      +
    276A  HIS*     3.0    48.2    -      +       +      -
    277A  PRO*     4.0     7.2    +      -       +      -
    279A  VAL*     3.8    18.6    -      -       +      +
    359A  GLN      4.7     0.4    -      -       -      -
    360A  LEU*     3.5    45.9    -      -       +      +
    363A  LYS*     3.1    40.1    -      -       +      +
    364A  SER*     4.1     6.7    -      -       -      -
    365A  GLU*     5.8     0.9    -      -       +      -
    369A  ASP*     3.3    18.5    +      -       -      -
    373A  LEU*     4.7     2.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 202 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200A  THR*     3.3     4.1    +      -       -      +
    201A  TYR*     1.3    80.9    -      -       -      +
    203A  ASP*     1.3    68.9    +      -       -      +
    205A  VAL*     3.3    10.8    +      -       +      +
    206A  LYS*     3.3    33.1    +      -       +      +
    267A  VAL*     4.6    16.0    -      -       +      +
    275A  PRO      4.7    11.4    -      -       -      +
    276A  HIS*     4.7     5.3    -      -       +      +
    277A  PRO*     3.8    33.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 203 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ARG*     4.0    15.8    +      -       -      -
    196A  SER*     5.0     7.4    +      -       -      -
    198A  GLU      5.3     4.0    -      -       -      +
    199A  GLN*     6.0     0.4    -      -       -      -
    200A  THR*     3.0    26.8    +      -       -      +
    202A  TYR*     1.3    82.2    -      -       -      +
    204A  LEU*     1.3    55.7    +      -       -      +
    206A  LYS*     3.1     7.0    +      -       -      +
    207A  ALA*     2.7    36.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 204 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199A  GLN*     5.1     4.0    -      -       +      +
    200A  THR      3.4    15.0    +      -       -      +
    201A  TYR*     3.1    24.0    -      -       -      +
    203A  ASP*     1.3    78.4    -      -       -      +
    205A  VAL*     1.3    80.7    +      -       +      +
    207A  ALA*     3.6     7.6    -      -       -      +
    208A  PHE*     2.8    31.6    +      -       +      +
    356A  LEU*     4.4    17.9    -      -       +      +
    359A  GLN*     4.3    35.2    -      -       +      +
    360A  LEU*     3.4    32.3    -      -       +      -
    363A  LYS*     5.0     4.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 205 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201A  TYR*     3.4    31.9    -      -       +      +
    202A  TYR*     3.3    11.8    +      -       +      +
    203A  ASP      3.1     0.6    -      -       -      -
    204A  LEU*     1.3    85.8    -      -       +      +
    206A  LYS*     1.3    59.9    +      -       -      +
    208A  PHE*     3.3     5.6    +      -       +      +
    209A  MET*     2.9    53.4    +      -       +      +
    263A  ILE*     4.5    14.1    -      -       +      -
    267A  VAL*     4.4    15.3    -      -       +      -
    277A  PRO*     5.6     6.7    -      -       +      -
    279A  VAL*     4.6    14.1    -      -       +      -
    360A  LEU*     4.9     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 206 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ARG*     3.4    15.5    +      -       -      +
    155A  TYR*     4.2    24.4    +      -       -      -
    202A  TYR*     3.3    25.1    +      -       +      +
    203A  ASP*     3.1    11.5    +      -       -      +
    205A  VAL*     1.3    78.8    -      -       -      +
    207A  ALA*     1.3    60.1    +      -       -      +
    209A  MET*     3.8    13.7    +      -       +      +
    210A  ALA*     3.3    16.8    +      -       -      +
    213A  ARG*     4.6    19.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 207 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ARG*     3.3    28.3    +      -       -      +
    203A  ASP*     2.7    25.1    +      -       -      +
    204A  LEU*     3.6     9.6    -      -       -      +
    206A  LYS*     1.3    72.4    -      -       -      +
    208A  PHE*     1.3    65.4    +      -       -      +
    209A  MET      3.2     0.2    -      -       -      -
    210A  ALA*     3.0     5.5    +      -       -      +
    211A  GLU*     2.9    29.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 208 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204A  LEU*     2.8    22.8    +      -       +      +
    205A  VAL*     3.8     4.7    -      -       +      +
    207A  ALA*     1.3    72.9    -      -       -      +
    209A  MET*     1.3    67.7    +      -       +      +
    211A  GLU*     3.0    11.2    +      -       +      +
    212A  ILE*     2.8    40.6    +      -       +      +
    259A  LEU*     3.7    23.3    -      -       +      -
    263A  ILE*     5.1     8.3    -      -       +      -
    283A  PHE*     5.4    10.1    -      +       -      -
    349A  HIS*     4.7     8.5    -      +       -      -
    352A  HIS*     4.2    16.2    -      +       -      -
    353A  TYR*     3.4    50.0    -      +       -      -
    356A  LEU*     3.6    31.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 209 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    205A  VAL*     2.9    33.0    +      -       -      +
    206A  LYS*     4.0    14.8    -      -       +      +
    208A  PHE*     1.3    79.1    -      -       +      +
    210A  ALA*     1.3    58.9    +      -       -      +
    212A  ILE*     3.3    13.5    -      -       +      +
    213A  ARG*     2.8    60.6    +      -       -      +
    260A  LEU*     4.3     0.6    -      -       +      +
    263A  ILE*     3.7    39.3    -      -       +      +
    264A  GLU*     3.5    28.9    -      -       +      -
    267A  VAL*     4.2    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 210 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ARG*     3.9    28.0    -      -       +      +
    155A  TYR*     4.1    11.9    -      -       -      +
    206A  LYS      3.3    13.0    +      -       -      +
    207A  ALA      3.0     9.9    +      -       -      +
    209A  MET*     1.3    80.1    -      -       -      +
    211A  GLU*     1.3    64.7    +      -       +      +
    213A  ARG*     3.5    12.8    +      -       -      +
    214A  GLN*     3.5    18.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 211 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  ARG*     5.2     9.5    +      -       -      -
    207A  ALA*     2.9    24.0    +      -       +      +
    208A  PHE*     3.0    13.9    +      -       +      +
    210A  ALA*     1.3    76.3    -      -       -      +
    212A  ILE*     1.3    60.7    +      -       -      +
    213A  ARG      3.1     1.6    -      -       -      -
    214A  GLN*     3.1    11.2    +      -       -      +
    215A  TYR*     2.8    27.9    +      -       -      +
    349A  HIS*     5.0     5.4    -      -       +      +
    352A  HIS*     5.6     9.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 212 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    208A  PHE*     2.8    29.5    +      -       +      +
    209A  MET*     3.3    19.1    -      -       +      +
    211A  GLU*     1.3    72.0    -      -       -      +
    213A  ARG*     1.3    60.6    +      -       -      +
    215A  TYR*     3.9     6.5    -      -       +      -
    216A  ILE*     2.9    46.3    +      -       +      +
    256A  SER*     3.4    30.1    -      -       -      +
    259A  LEU*     3.7    26.9    -      -       +      -
    260A  LEU*     3.6    22.7    -      -       +      -
    263A  ILE*     5.4     0.7    -      -       +      -
    349A  HIS*     4.2    15.4    -      -       +      -
    353A  TYR*     4.1    11.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 213 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150A  ARG*     3.6    29.5    +      -       -      +
    155A  TYR*     5.3     2.2    +      -       -      -
    206A  LYS*     4.6    17.1    +      -       -      +
    209A  MET*     2.8    67.8    +      -       -      +
    210A  ALA*     3.5    16.1    -      -       -      +
    211A  GLU      3.1     0.8    -      -       -      -
    212A  ILE*     1.3    77.8    -      -       -      +
    214A  GLN*     1.3    61.8    +      -       -      +
    216A  ILE*     3.6     9.0    +      -       -      +
    217A  ARG*     3.2    16.8    +      -       -      +
    260A  LEU*     4.3    14.4    -      -       +      -
    264A  GLU*     2.9    28.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 214 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    150A  ARG*     3.2    21.6    +      -       -      +
    151A  ASN*     2.9    48.2    +      -       -      +
    210A  ALA      3.5    10.1    +      -       -      +
    211A  GLU*     3.1    13.6    +      -       -      +
    213A  ARG*     1.3    75.4    -      -       -      +
    215A  TYR*     1.3    67.5    +      -       -      +
    217A  ARG*     3.1    14.3    +      -       -      +
    218A  GLU*     3.0    49.2    +      -       -      +
    551A  GLU*     5.4     4.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 215 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  GLU      2.8    15.3    +      -       -      +
    212A  ILE*     3.5     5.6    -      -       +      +
    214A  GLN*     1.3    76.9    -      -       -      +
    216A  ILE*     1.3    63.6    +      -       -      +
    218A  GLU*     2.9    30.4    +      -       -      +
    219A  LEU*     2.9    40.6    +      -       +      +
    252A  ILE*     3.2    15.9    -      -       -      +
    256A  SER*     3.2    26.9    -      -       -      -
    295A  TYR*     3.5     3.0    +      -       -      -
    345A  ALA*     4.1     5.8    -      -       +      -
    346A  PRO*     3.1    39.3    -      -       +      +
    349A  HIS*     3.4    55.9    -      +       +      +
----------------------------------------------------------
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Residues in contact with ILE 216 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    212A  ILE*     2.9    31.7    +      -       +      +
    213A  ARG*     3.9     6.5    -      -       -      +
    215A  TYR*     1.3    72.4    -      -       +      +
    217A  ARG*     1.3    61.9    +      -       -      +
    219A  LEU*     3.3     9.3    +      -       -      +
    220A  ASN*     3.0    38.5    +      -       -      +
    253A  HIS*     4.0    16.2    -      -       +      +
    256A  SER*     3.6    45.8    -      -       -      +
    257A  VAL*     3.8    13.7    -      -       +      +
    260A  LEU*     3.9    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 217 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147A  ASN*     3.4    31.7    +      -       -      +
    150A  ARG*     3.4    29.7    -      -       -      +
    151A  ASN*     5.0     4.8    +      -       -      +
    213A  ARG      3.2    12.9    +      -       -      +
    214A  GLN*     3.1    22.5    +      -       -      +
    215A  TYR      3.1     0.6    -      -       -      -
    216A  ILE*     1.3    78.6    -      -       -      +
    218A  GLU*     1.3    62.1    +      -       +      +
    220A  ASN*     3.4     7.9    +      -       -      +
    221A  LEU*     3.1    20.8    +      -       -      +
    551A  GLU*     2.7    32.4    +      -       -      +
    554A  LEU*     3.7    17.5    -      -       +      +
    555A  ASP*     3.1    28.0    +      -       -      -
    558A  MET*     6.3     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 218 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    214A  GLN*     3.0    38.6    +      -       -      +
    215A  TYR*     2.9    17.6    +      -       +      +
    217A  ARG*     1.3    73.8    -      -       +      +
    219A  LEU*     1.3    67.0    +      -       +      +
    221A  LEU*     3.1    16.1    +      -       +      +
    222A  ILE*     3.0    32.8    +      -       +      +
    342A  LEU*     6.4     3.4    -      -       +      -
    345A  ALA*     3.8    24.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 219 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215A  TYR*     2.9    64.0    +      -       +      +
    216A  ILE*     3.4    14.6    -      -       -      +
    218A  GLU*     1.3    77.2    -      -       +      +
    220A  ASN*     1.3    56.6    +      -       -      +
    222A  ILE*     2.9    11.0    +      -       +      +
    223A  ILE*     2.8    36.7    +      -       +      +
    249A  ILE*     4.2    24.0    -      -       +      +
    252A  ILE*     4.4     1.8    -      -       +      +
    253A  HIS*     3.7    40.6    -      -       +      +
    256A  SER*     4.0     5.8    -      -       -      +
    345A  ALA*     6.2     0.9    -      -       +      -
    346A  PRO*     4.5     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 220 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216A  ILE*     3.0    20.3    +      -       -      +
    217A  ARG*     3.7     8.4    -      -       -      +
    218A  GLU      3.3     0.2    -      -       -      -
    219A  LEU*     1.3    75.1    -      -       -      +
    221A  LEU*     1.3    58.0    +      -       -      +
    223A  ILE*     4.4     6.6    -      -       -      +
    224A  LYS*     2.8    43.2    +      -       +      +
    225A  VAL      3.9     0.2    +      -       -      -
    253A  HIS*     2.9    35.3    +      -       -      -
    554A  LEU*     3.7    16.8    -      -       +      +
    558A  MET*     3.5    29.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 221 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    217A  ARG      3.1    12.5    +      -       -      +
    218A  GLU*     3.1    17.7    +      -       +      +
    219A  LEU      3.1     0.4    -      -       -      -
    220A  ASN*     1.3    79.1    -      -       -      +
    222A  ILE*     1.3    58.5    +      -       +      +
    225A  VAL*     3.0    47.2    -      -       +      +
    226A  PHE*     3.1    15.9    -      -       +      -
    342A  LEU*     4.9    11.2    -      -       +      -
    550A  LEU*     3.6    50.9    -      -       +      +
    551A  GLU*     4.3    17.3    -      -       -      +
    554A  LEU*     3.8    13.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 222 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    218A  GLU*     3.0    22.4    +      -       +      +
    219A  LEU*     2.9    14.6    +      -       +      +
    221A  LEU*     1.3    78.3    -      -       +      +
    223A  ILE*     1.3    59.6    +      -       +      +
    226A  PHE*     3.3    10.3    -      -       +      +
    227A  ARG*     2.8    26.2    +      -       -      +
    246A  PHE*     3.8    15.0    -      -       +      -
    249A  ILE*     4.4    19.1    -      -       +      -
    339A  LEU*     4.3     6.1    -      -       +      -
    342A  LEU*     3.3    46.7    -      -       +      +
    343A  LEU*     3.6    28.0    -      -       +      -
    345A  ALA*     5.7     1.1    -      -       +      -
    346A  PRO*     5.5     2.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 223 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219A  LEU*     2.8    22.6    +      -       +      +
    220A  ASN*     4.2     5.2    -      -       -      +
    222A  ILE*     1.3    80.9    -      -       -      +
    224A  LYS*     1.3    70.5    +      -       +      +
    225A  VAL      3.4     0.2    -      -       -      -
    227A  ARG*     3.2    17.0    +      -       -      +
    228A  GLU*     3.0    27.0    +      -       -      +
    249A  ILE*     4.3    21.5    -      -       +      +
    250A  VAL*     4.2    28.5    -      -       +      -
    253A  HIS*     3.8    37.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 224 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    220A  ASN*     2.8    30.1    +      -       +      +
    223A  ILE*     1.3    85.3    -      -       +      +
    225A  VAL*     1.3    62.3    +      -       -      +
    228A  GLU*     3.5    23.5    -      -       -      +
    253A  HIS*     5.8     4.8    +      -       -      -
    554A  LEU*     4.7     4.0    -      -       +      -
    557A  THR*     4.0    24.6    +      -       +      +
    558A  MET*     3.2    39.4    -      -       -      +
    561A  GLU*     2.8    39.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 225 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    221A  LEU*     3.0    34.4    +      -       +      +
    223A  ILE      3.4     0.2    -      -       -      -
    224A  LYS*     1.3    86.0    -      -       -      +
    226A  PHE*     1.3    60.6    +      -       +      +
    229A  PRO*     3.2    22.5    -      -       -      +
    331A  PHE*     3.7    15.5    -      -       +      -
    550A  LEU*     3.6    30.1    -      -       +      -
    553A  MET*     4.5    22.6    -      -       +      +
    554A  LEU*     3.9    30.5    -      -       +      +
    557A  THR*     5.1     0.9    -      -       -      +
----------------------------------------------------------
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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