Contacts of the helix formed by residues 183 - 211 (chain B) in PDB entry 2XWU


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 PRO 183 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181B  ARG      4.7     0.2    -      -       -      +
    182B  LEU*     1.3    88.6    -      -       +      +
    184B  GLN*     1.3    59.9    +      -       -      +
    185B  TYR*     4.2     4.3    -      -       +      +
    186B  ARG*     2.7    34.6    +      -       +      +
    187B  LYS*     2.5    34.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 184 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182B  LEU      3.9     2.0    +      -       -      -
    183B  PRO*     1.3    71.1    -      -       -      +
    185B  TYR*     1.3    61.6    +      -       -      +
    187B  LYS*     4.1     5.0    -      -       -      +
    188B  GLY*     3.1    18.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 185 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183B  PRO*     2.9     5.4    +      -       +      +
    184B  GLN*     1.3    80.8    -      -       -      +
    186B  ARG*     1.3    65.6    +      -       -      +
    188B  GLY*     4.1     0.7    -      -       -      -
    189B  LEU*     3.5    17.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 186 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  LEU      3.1    15.6    +      -       -      -
    133B  SER*     3.0    33.5    +      -       -      +
    135B  MET      3.4    12.6    +      -       -      -
    136B  PRO*     4.7     3.2    -      -       -      +
    182B  LEU*     3.8    19.1    -      -       +      +
    183B  PRO*     2.7    40.5    +      -       +      +
    185B  TYR*     1.3    74.8    -      -       -      +
    187B  LYS*     1.3    63.8    +      -       -      +
    189B  LEU*     3.1    17.8    +      -       -      +
    190B  VAL*     2.6    43.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 187 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177B  PHE*     4.1    12.7    -      -       +      -
    182B  LEU*     4.0    22.2    -      -       +      +
    183B  PRO      2.5    21.9    +      -       -      +
    184B  GLN*     4.1     4.0    -      -       -      +
    186B  ARG*     1.3    74.6    -      -       -      +
    188B  GLY*     1.3    56.8    +      -       -      +
    190B  VAL*     3.4     7.0    +      -       -      +
    191B  ARG*     2.8    31.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 188 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184B  GLN      3.1    16.7    +      -       -      -
    185B  TYR      3.5     1.7    +      -       -      -
    186B  ARG      3.2     0.6    -      -       -      -
    187B  LYS*     1.3    77.7    -      -       -      +
    189B  LEU*     1.3    54.3    +      -       -      +
    191B  ARG*     3.3     5.9    +      -       -      +
    192B  THR*     2.4    41.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 189 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136B  PRO*     4.2    26.7    -      -       +      +
    185B  TYR      3.5    10.8    +      -       -      +
    186B  ARG*     3.1    14.0    +      -       -      +
    188B  GLY*     1.3    77.9    -      -       -      +
    190B  VAL*     1.3    57.3    +      -       -      +
    192B  THR*     3.3     6.9    +      -       -      -
    193B  SER*     3.0    29.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 190 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  LEU*     3.9    29.6    -      -       +      +
    135B  MET*     3.8    15.5    -      -       +      +
    177B  PHE*     3.3    32.3    -      -       +      -
    182B  LEU*     4.2    10.5    -      -       +      -
    186B  ARG*     2.6    49.8    +      -       -      +
    187B  LYS*     3.7     7.9    -      -       -      +
    189B  LEU*     1.3    74.5    -      -       -      +
    191B  ARG*     1.3    59.7    +      -       -      +
    193B  SER      3.3     1.2    +      -       -      -
    194B  LEU*     2.8    28.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 191 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177B  PHE*     3.3    33.0    -      -       +      -
    187B  LYS      2.8    19.8    +      -       -      +
    188B  GLY*     3.7     6.3    -      -       -      +
    190B  VAL*     1.3    75.3    -      -       -      +
    192B  THR*     1.3    58.7    +      -       -      +
    194B  LEU*     3.2     9.3    +      -       -      +
    195B  ALA*     2.9    50.2    +      -       -      +
    232B  LEU*     2.6    51.7    +      -       -      +
    233B  GLU*     4.2    11.7    +      -       -      +
    234B  VAL*     4.5     5.3    -      -       -      +
    235B  PRO*     6.0     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 192 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188B  GLY      2.4    27.2    +      -       -      -
    189B  LEU*     3.4     8.0    -      -       -      -
    191B  ARG*     1.3    74.4    -      -       -      +
    193B  SER*     1.3    67.6    +      -       -      +
    195B  ALA*     3.2    16.7    +      -       -      +
    196B  VAL*     3.3    18.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 193 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135B  MET*     3.6    23.6    -      -       -      -
    136B  PRO*     3.9    24.0    -      -       -      -
    189B  LEU      3.0    16.2    +      -       -      -
    190B  VAL      3.9     0.4    -      -       -      -
    192B  THR*     1.3    76.1    -      -       -      +
    194B  LEU*     1.3    57.0    +      -       -      +
    196B  VAL*     3.1    12.0    +      -       -      +
    197B  GLU*     3.0    31.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 194 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  LEU*     3.7    26.5    -      -       +      -
    135B  MET*     3.5    19.2    -      -       +      +
    173B  LEU*     4.4    11.9    -      -       +      -
    174B  PRO*     5.2     4.7    -      -       +      -
    177B  PHE*     3.7    32.1    -      -       +      -
    190B  VAL      2.8    15.7    +      -       -      +
    191B  ARG*     3.3    13.7    -      -       -      +
    193B  SER*     1.3    74.9    -      -       -      +
    195B  ALA*     1.3    63.2    +      -       -      +
    197B  GLU*     3.3    11.0    +      -       +      +
    198B  CYS      3.2    16.5    +      -       -      -
    229B  TRP*     3.6    34.1    -      -       +      -
    232B  LEU*     4.5    10.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 195 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191B  ARG*     2.9    31.5    +      -       -      +
    192B  THR*     3.2    11.2    +      -       -      +
    194B  LEU*     1.3    76.5    -      -       -      +
    196B  VAL*     1.3    62.9    +      -       +      +
    198B  CYS*     3.4    19.1    +      -       -      +
    199B  GLY      4.1     2.3    +      -       -      -
    234B  VAL*     5.6     5.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 196 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192B  THR*     3.6    17.5    -      -       +      +
    193B  SER*     3.1    12.5    +      -       -      +
    195B  ALA*     1.3    75.3    -      -       +      +
    197B  GLU*     1.3    68.7    +      -       -      +
    198B  CYS      3.1     2.0    -      -       -      -
    199B  GLY*     3.1    15.6    +      -       -      -
    200B  ALA      4.3     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 197 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135B  MET*     4.2    15.2    -      -       +      +
    139B  TRP      4.3     2.3    -      -       -      +
    140B  PRO      3.3    16.2    -      -       -      +
    141B  CYS*     4.1     5.7    -      -       -      +
    142B  ALA*     2.9    34.2    +      -       +      +
    143B  VAL*     3.4    46.0    +      -       +      +
    144B  ALA      4.6     0.9    +      -       -      -
    173B  LEU*     6.0     0.4    -      -       +      -
    193B  SER*     3.0    22.0    +      -       -      +
    194B  LEU*     3.3    16.8    +      -       +      +
    196B  VAL*     1.3    80.2    -      -       -      +
    198B  CYS*     1.3    56.8    +      -       -      +
    199B  GLY      3.0     0.7    -      -       -      -
    200B  ALA*     3.0    19.4    +      -       -      +
    201B  VAL*     3.4     3.6    +      -       -      +
    229B  TRP*     4.6     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 198 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    194B  LEU      3.2     6.6    +      -       -      +
    195B  ALA*     3.4    15.5    -      -       -      +
    196B  VAL      3.1     1.2    -      -       -      -
    197B  GLU*     1.3    75.0    -      -       -      +
    199B  GLY*     1.3    62.4    +      -       -      +
    200B  ALA      3.2     0.4    -      -       -      -
    201B  VAL*     3.8     4.5    -      -       -      -
    202B  PHE*     3.3    55.6    +      -       -      +
    229B  TRP*     3.7    31.8    -      -       +      -
    234B  VAL*     4.0    23.3    -      -       +      -
    238B  ASP*     6.2     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 199 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195B  ALA      4.1     1.8    +      -       -      -
    196B  VAL      3.1    11.7    +      -       -      -
    197B  GLU      3.0     2.0    -      -       -      -
    198B  CYS*     1.3    80.0    -      -       -      +
    200B  ALA*     1.3    58.3    +      -       -      +
    202B  PHE*     5.7     0.2    -      -       -      -
    203B  PRO*     2.8    26.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 200 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143B  VAL*     3.3    28.0    -      -       +      +
    144B  ALA*     4.5    11.9    -      -       +      +
    147B  VAL*     5.2     3.6    -      -       +      +
    196B  VAL      4.3     1.0    +      -       -      -
    197B  GLU*     3.0     8.2    +      -       -      +
    199B  GLY*     1.3    79.4    -      -       -      +
    201B  VAL*     1.3    65.6    +      -       -      +
    203B  PRO*     3.5     9.6    -      -       -      +
    204B  LEU*     3.7    12.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 201 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143B  VAL*     3.7    12.6    -      -       +      -
    170B  LEU*     3.6    28.0    -      -       +      -
    197B  GLU      3.4     6.8    +      -       -      +
    198B  CYS*     3.5     7.8    +      -       -      +
    199B  GLY      3.5     0.2    -      -       -      -
    200B  ALA*     1.3    74.6    -      -       -      +
    202B  PHE*     1.3    73.1    +      -       +      +
    204B  LEU*     3.0    17.8    +      -       -      +
    205B  LEU*     3.2    26.5    +      -       +      +
    225B  CYS*     4.6     4.9    -      -       -      -
    229B  TRP*     3.4    53.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 202 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198B  CYS*     3.3    33.6    +      -       -      +
    201B  VAL*     1.3    81.7    -      -       +      +
    203B  PRO*     1.4    72.9    -      -       +      +
    205B  LEU*     2.8    12.0    +      -       +      +
    206B  GLU*     2.8    35.8    +      -       -      +
    226B  PHE*     3.6    32.8    -      +       -      -
    229B  TRP*     3.9    19.1    -      +       +      -
    230B  VAL*     5.2     0.4    -      -       +      -
    234B  VAL*     4.0    17.3    -      -       +      -
    238B  ASP*     3.4    29.4    -      -       +      -
    239B  CYS*     3.7    21.8    -      -       -      -
    242B  LEU*     3.9    14.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 203 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199B  GLY*     2.8    30.5    -      -       -      +
    200B  ALA*     3.5     6.5    -      -       -      +
    201B  VAL      3.4     3.1    -      -       -      -
    202B  PHE*     1.4    93.0    -      -       +      +
    204B  LEU*     1.3    62.1    +      -       -      +
    206B  GLU*     3.3    16.3    +      -       -      +
    207B  GLN*     3.0    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 204 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147B  VAL*     3.5    34.3    -      -       +      -
    151B  GLN*     5.2     5.6    -      -       -      +
    163B  CYS*     6.1     0.7    -      -       -      -
    166B  LEU*     3.6    20.0    -      -       +      -
    167B  LEU*     5.3     2.0    -      -       +      -
    170B  LEU*     3.8    20.4    -      -       +      -
    200B  ALA      3.7     8.2    +      -       -      +
    201B  VAL      3.0     9.7    +      -       -      +
    203B  PRO*     1.3    77.9    -      -       -      +
    205B  LEU*     1.3    66.9    +      -       +      +
    207B  GLN*     3.2    19.1    +      -       +      +
    208B  LEU*     3.2    45.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 205 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167B  LEU*     3.7    29.4    -      -       +      -
    170B  LEU*     5.3     1.6    -      -       +      -
    201B  VAL*     3.5    28.9    -      -       +      +
    202B  PHE*     2.8    10.4    +      -       +      +
    204B  LEU*     1.3    78.8    -      -       +      +
    206B  GLU*     1.3    64.6    +      -       -      +
    208B  LEU*     3.4     4.2    +      -       -      +
    209B  LEU*     3.2    28.9    +      -       -      +
    222B  VAL*     3.9    20.6    -      -       +      +
    225B  CYS*     4.0    14.1    -      -       +      +
    226B  PHE*     4.0    26.5    -      -       -      +
    242B  LEU*     3.8    26.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 206 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202B  PHE*     2.8    37.3    +      -       -      +
    203B  PRO*     3.5    14.6    -      -       -      +
    205B  LEU*     1.3    75.8    -      -       -      +
    207B  GLN*     1.3    65.1    +      -       -      +
    209B  LEU*     3.2     5.8    +      -       -      +
    210B  GLN*     3.0    24.9    +      -       -      +
    238B  ASP      5.1     2.4    -      -       -      +
    241B  ALA*     3.4    29.8    -      -       +      +
    242B  LEU*     3.9    24.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 207 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151B  GLN*     5.7     2.6    +      -       -      -
    203B  PRO*     3.0    18.9    +      -       -      +
    204B  LEU*     3.3    23.2    -      -       +      +
    206B  GLU*     1.3    75.6    -      -       -      +
    208B  LEU*     1.3    66.2    +      -       +      +
    210B  GLN*     3.1    16.4    +      -       -      +
    211B  GLN*     3.1    15.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 208 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163B  CYS*     3.9    31.4    -      -       -      -
    167B  LEU*     4.0    13.0    -      -       +      -
    204B  LEU*     3.2    34.9    +      -       +      +
    205B  LEU*     3.8     6.1    -      -       -      +
    206B  GLU      3.4     0.2    -      -       -      -
    207B  GLN*     1.3    80.4    -      -       +      +
    209B  LEU*     1.3    61.3    +      -       -      +
    211B  GLN*     3.6     4.6    -      -       +      +
    214B  SER*     2.4    39.8    +      -       -      +
    218B  VAL*     4.5     6.1    -      -       +      -
    222B  VAL*     3.7    28.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 209 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    205B  LEU      3.2     5.2    -      -       -      +
    206B  GLU*     3.2     7.3    +      -       -      +
    207B  GLN      3.2     0.6    -      -       -      -
    208B  LEU*     1.3    74.3    -      -       -      +
    210B  GLN*     1.3    59.6    +      -       -      +
    211B  GLN      3.1     5.2    -      -       -      -
    219B  ARG*     2.4    46.0    +      -       +      +
    222B  VAL*     3.0    42.8    -      -       +      -
    223B  LEU*     5.0    13.0    -      -       +      -
    242B  LEU*     3.8    19.3    -      -       +      +
    245B  ALA*     3.6    37.7    -      -       +      +
    246B  ALA      5.0     1.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 210 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    206B  GLU      3.0    15.5    +      -       -      +
    207B  GLN*     3.7     5.2    -      -       -      +
    209B  LEU*     1.3    75.9    -      -       -      +
    211B  GLN*     1.3    58.4    +      -       -      +
    212B  PRO*     3.0    14.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 211 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    207B  GLN      3.1    14.8    +      -       -      +
    208B  LEU*     4.3     1.6    -      -       +      -
    209B  LEU      3.1     2.4    -      -       -      -
    210B  GLN*     1.3    77.5    -      -       -      +
    212B  PRO*     1.3    63.4    -      -       -      +
    213B  SER*     2.9    22.0    +      -       -      +
    214B  SER*     3.0    28.5    +      -       -      +
    219B  ARG*     3.6     6.4    +      -       -      -
----------------------------------------------------------
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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