Contacts of the helix formed by residues 281 - 307 (chain B) in PDB entry 2BG9


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 ILE 281 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132B  VAL*     6.3     0.7    -      -       +      -
    279B  ILE      4.5     4.5    -      -       -      +
    280B  ILE*     1.3    85.4    -      -       +      +
    282B  SER*     1.3    53.9    +      -       -      +
    283B  TYR*     3.3     2.0    -      -       -      -
    284B  LEU*     2.4    54.4    +      -       +      +
    285B  MET*     2.5    55.9    +      -       +      +
    288B  MET*     5.5     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 282 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136B  PRO*     6.4     0.4    -      -       -      -
    137B  PHE*     5.4     0.6    -      -       -      -
    280B  ILE*     3.3    17.2    -      -       -      +
    281B  ILE*     1.3    77.1    -      -       -      +
    283B  TYR*     1.3    87.0    +      -       -      -
    285B  MET*     3.1    28.8    +      -       -      +
    286B  PHE*     2.6    31.5    +      -       -      -
    460B  HIS*     3.3    33.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 283 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135B  PHE*     4.1    42.3    +      +       +      -
    136B  PRO*     5.7     1.1    -      -       +      -
    137B  PHE*     2.7    46.0    -      +       -      -
    221B  ILE*     4.9    26.2    -      -       +      -
    280B  ILE*     5.1     5.6    -      -       +      -
    281B  ILE      2.7     2.6    +      -       -      +
    282B  SER*     1.3    95.5    +      -       -      +
    284B  LEU*     1.3    55.2    +      -       -      +
    286B  PHE*     3.3    15.1    -      +       +      -
    287B  ILE*     2.7    42.0    +      -       +      +
    457B  ASP*     4.7     9.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 284 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    270B  VAL*     3.7    34.3    -      -       +      +
    271B  PRO*     6.3     0.4    -      -       +      -
    274B  SER*     5.5     8.7    -      -       -      +
    281B  ILE*     2.4    32.0    +      -       +      +
    283B  TYR*     1.3    72.9    -      -       +      +
    285B  MET*     1.3    52.0    +      -       -      +
    287B  ILE*     3.2    27.1    -      -       +      -
    288B  MET*     2.5    56.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 285 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    280B  ILE*     6.5     0.2    -      -       -      -
    281B  ILE*     2.5    42.8    +      -       +      +
    282B  SER*     3.2    27.1    -      -       -      +
    284B  LEU*     1.3    73.2    -      -       -      +
    286B  PHE*     1.3    63.4    +      -       +      +
    288B  MET*     2.9    11.8    -      -       -      +
    289B  ILE*     2.9    23.6    -      -       +      +
    456B  LEU*     6.0     3.6    -      -       +      -
    460B  HIS*     5.2     7.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 286 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282B  SER*     2.6    37.7    -      -       -      -
    283B  TYR*     3.3    13.5    -      +       +      -
    285B  MET*     1.3    79.3    -      -       +      +
    287B  ILE*     1.3    83.7    +      -       +      +
    288B  MET      2.9     5.6    -      -       -      -
    289B  ILE*     2.7    15.5    +      -       +      +
    290B  LEU*     2.4    49.9    +      -       +      +
    453B  SER*     3.3    15.7    -      -       -      -
    456B  LEU*     4.4    12.3    -      -       +      -
    457B  ASP*     2.7    42.0    -      -       -      -
    460B  HIS*     3.7    20.9    -      +       -      -
----------------------------------------------------------
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Residues in contact with ILE 287 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224B  THR*     6.0     6.3    -      -       +      -
    228B  CYS*     5.1    14.2    -      -       -      -
    270B  VAL*     6.0     4.5    -      -       +      -
    283B  TYR*     2.7    36.4    +      -       +      +
    284B  LEU*     3.2    33.4    -      -       +      -
    286B  PHE*     1.3    94.7    -      -       +      +
    288B  MET*     1.3    57.9    +      -       -      +
    290B  LEU*     3.1    16.3    -      -       +      +
    291B  VAL*     2.4    42.9    +      -       +      +
    457B  ASP*     5.3     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 288 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216A  VAL*     5.2    14.4    -      -       +      -
    217A  ASN*     5.5    12.6    -      -       +      +
    220A  ILE*     5.8     3.4    -      -       +      -
    281B  ILE*     6.0     2.9    -      -       +      -
    284B  LEU*     2.5    35.6    +      -       +      +
    285B  MET*     2.9    13.9    -      -       -      +
    287B  ILE*     1.3    79.3    -      -       +      +
    289B  ILE*     1.3    61.2    +      -       +      +
    291B  VAL*     2.6    37.7    -      -       +      +
    292B  ALA*     2.9    10.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 289 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285B  MET*     2.9    21.5    -      -       +      +
    286B  PHE*     3.0    16.8    -      -       +      +
    288B  MET*     1.3    83.8    -      -       +      +
    290B  LEU*     1.3    50.2    +      -       +      +
    291B  VAL      3.0     1.3    -      -       -      -
    292B  ALA*     3.1     6.1    +      -       +      +
    293B  PHE*     2.6    85.6    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 290 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228B  CYS*     5.2    14.8    -      -       +      -
    286B  PHE*     2.4    38.5    +      -       +      +
    287B  ILE*     3.1    33.4    -      -       +      +
    289B  ILE*     1.3    72.9    -      -       +      +
    291B  VAL*     1.3    62.3    +      -       -      +
    293B  PHE*     3.3    10.8    -      -       +      +
    294B  SER*     3.0    25.8    +      -       -      -
    449B  ILE*     3.9    22.9    -      -       +      +
    450B  GLY*     4.8     4.7    -      -       -      -
    453B  SER*     2.8    32.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 291 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263B  LEU*     3.3    36.8    -      -       +      +
    287B  ILE*     2.4    31.5    +      -       +      +
    288B  MET*     2.6    29.6    -      -       +      +
    290B  LEU*     1.3    72.5    -      -       -      +
    292B  ALA*     1.3    79.6    +      -       +      +
    293B  PHE      2.9     1.8    +      -       -      -
    294B  SER*     3.1     2.6    +      -       -      -
    295B  VAL*     2.7    46.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 292 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    288B  MET*     2.9    10.5    +      -       +      +
    289B  ILE*     3.4    12.8    -      -       +      +
    291B  VAL*     1.3    84.0    -      -       +      +
    293B  PHE*     1.3    63.9    +      -       +      +
    295B  VAL*     3.4     8.7    -      -       -      +
    296B  ILE*     2.9    39.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 293 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289B  ILE*     2.6    55.9    +      -       +      +
    290B  LEU*     3.3    13.7    -      -       +      +
    291B  VAL      2.9     1.2    -      -       -      -
    292B  ALA*     1.3    79.1    -      -       +      +
    294B  SER*     1.3    52.7    +      -       -      +
    296B  ILE*     4.2     2.1    -      -       +      +
    297B  LEU*     2.7    40.8    +      -       -      +
    445B  THR*     5.8     1.3    -      -       +      -
    449B  ILE*     3.5    55.2    -      -       +      -
    452B  PHE*     6.1     0.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with SER 294 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228B  CYS      5.3     1.6    +      -       -      -
    231B  ILE*     5.4     4.4    -      -       -      +
    232B  SER*     4.8     9.9    +      -       -      -
    235B  ALA*     4.8    11.6    -      -       -      +
    239B  PHE*     5.5     4.3    -      -       -      -
    259B  LEU*     5.2     8.1    -      -       -      +
    263B  LEU*     5.0    15.7    -      -       -      -
    290B  LEU      3.0    17.4    +      -       -      -
    291B  VAL*     3.9     2.5    -      -       -      -
    293B  PHE*     1.3    71.4    -      -       -      +
    295B  VAL*     1.3    59.9    +      -       -      +
    297B  LEU*     4.3     6.1    -      -       -      -
    298B  SER*     2.8    32.6    +      -       -      -
    449B  ILE*     5.3     0.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 295 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224A  LEU*     5.9     7.9    -      -       +      -
    259B  LEU*     6.4     0.7    -      -       -      -
    260B  THR*     6.0     8.7    -      -       +      +
    263B  LEU*     5.4    13.2    -      -       +      -
    291B  VAL*     2.7    42.8    +      -       +      +
    292B  ALA*     3.4     9.9    -      -       -      +
    294B  SER*     1.3    72.6    -      -       -      +
    296B  ILE*     1.3    68.3    +      -       +      +
    298B  SER*     2.6    21.7    +      -       -      -
    299B  VAL*     2.9    22.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 296 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227A  PHE*     5.8     6.1    -      -       +      -
    292B  ALA*     2.9    23.3    +      -       +      +
    293B  PHE*     4.2     2.0    -      -       +      +
    295B  VAL*     1.3    78.6    -      -       +      +
    297B  LEU*     1.3    58.5    +      -       -      +
    298B  SER      3.2     1.8    -      -       -      -
    299B  VAL*     3.5    13.5    -      -       +      -
    300B  VAL*     2.6    42.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 297 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239B  PHE*     4.9    11.4    -      -       +      -
    293B  PHE      2.7    25.0    +      -       -      +
    294B  SER*     4.1     4.3    -      -       -      +
    296B  ILE*     1.3    75.5    -      -       -      +
    298B  SER*     1.3    58.5    +      -       -      +
    300B  VAL*     3.7     9.0    -      -       +      +
    301B  VAL*     2.8    56.0    +      -       +      +
    441B  TYR*     4.7     9.2    -      -       +      +
    442B  ILE*     3.9    21.8    -      -       +      -
    445B  THR*     3.1    44.4    -      -       +      +
    446B  MET*     5.0     4.9    -      -       +      +
    449B  ILE*     5.3     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 298 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239B  PHE*     4.4    13.4    -      -       -      -
    256B  LEU*     2.8    49.2    -      -       -      +
    259B  LEU*     4.9     6.7    -      -       -      +
    260B  THR*     5.2     3.8    +      -       -      -
    294B  SER      2.8    16.0    +      -       -      -
    295B  VAL*     2.6    23.4    +      -       -      -
    297B  LEU*     1.3    74.3    -      -       -      +
    299B  VAL*     1.3    57.9    +      -       -      +
    301B  VAL*     2.6    29.6    -      -       -      +
    302B  LEU      3.1     3.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 299 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224A  LEU*     5.5    10.8    -      -       +      -
    227A  PHE*     4.2    26.7    -      -       +      -
    228A  LEU*     4.9    10.8    -      -       +      -
    231A  LEU*     4.5    13.3    -      -       +      +
    256B  LEU*     5.0     2.0    -      -       +      -
    260B  THR*     5.6     5.2    -      -       -      +
    295B  VAL*     2.9    29.4    +      -       +      +
    296B  ILE*     3.1    15.8    +      -       +      +
    298B  SER*     1.3    81.4    +      -       -      +
    300B  VAL*     1.3    61.3    +      -       -      +
    302B  LEU*     2.8    16.4    -      -       +      +
    303B  ASN*     2.8    22.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 300 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227A  PHE*     5.6     6.3    -      -       +      -
    296B  ILE*     2.6    32.0    +      -       +      +
    297B  LEU*     3.7    13.9    -      -       +      +
    299B  VAL*     1.3    71.1    -      -       -      +
    301B  VAL*     1.3    61.4    +      -       +      +
    302B  LEU      2.9     1.6    -      -       -      -
    303B  ASN*     2.7    17.7    +      -       +      +
    304B  LEU*     2.4    32.2    +      -       -      +
    441B  TYR*     5.5     8.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 301 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238B  VAL*     5.2     1.3    -      -       +      -
    239B  PHE*     4.3    18.8    -      -       +      -
    256B  LEU*     4.8     0.9    -      -       +      -
    297B  LEU*     2.8    42.5    +      -       +      +
    298B  SER*     2.6    37.2    -      -       -      +
    300B  VAL*     1.3    79.8    -      -       +      +
    302B  LEU*     1.3    51.8    +      -       -      +
    304B  LEU*     2.8    19.5    +      -       +      +
    305B  HIS*     2.5    51.3    +      -       +      +
    442B  ILE*     3.8    17.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 302 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228A  LEU*     4.2    21.5    -      -       +      -
    231A  LEU*     4.9     9.2    -      -       +      -
    235A  LEU*     5.8     1.9    -      -       +      +
    242A  LYS*     4.3     4.9    +      -       -      +
    252B  SER*     4.9     1.1    -      -       -      +
    253B  ILE*     3.2    51.4    -      -       +      +
    256B  LEU*     3.3    29.8    -      -       +      -
    298B  SER      3.2     6.3    -      -       -      +
    299B  VAL*     2.8    19.5    -      -       +      +
    301B  VAL*     1.3    83.2    -      -       -      +
    303B  ASN*     1.3    55.2    +      -       -      +
    305B  HIS*     3.1    21.7    +      -       +      +
    306B  HIS*     2.8    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 303 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227A  PHE*     2.8    36.6    -      -       +      -
    231A  LEU*     3.6    16.4    -      -       +      +
    299B  VAL      2.8    11.5    +      -       -      +
    300B  VAL*     2.7    21.8    +      -       +      +
    302B  LEU*     1.3    75.8    -      -       -      +
    304B  LEU*     1.3    65.1    +      -       -      +
    305B  HIS      3.1     0.2    -      -       -      -
    306B  HIS*     3.9    14.0    -      -       -      +
    307B  ARG*     3.0    25.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 304 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    242B  PRO*     6.1     3.1    -      -       +      -
    300B  VAL      2.4    18.3    +      -       -      +
    301B  VAL*     2.9    32.5    -      -       +      +
    303B  ASN*     1.3    71.8    -      -       -      +
    305B  HIS*     1.3    77.8    +      -       +      +
    307B  ARG*     3.8    28.9    +      -       -      +
    434B  VAL*     3.8    32.1    -      -       +      -
    435B  ALA*     4.4    19.3    -      -       +      +
    438B  LEU*     4.2    21.8    -      -       +      -
    442B  ILE*     5.1     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 305 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    242A  LYS*     4.3     2.5    -      -       -      +
    238B  VAL*     4.1    23.2    +      -       +      +
    239B  PHE*     6.0     0.2    -      -       -      -
    242B  PRO*     4.3    15.6    -      -       +      +
    248B  LYS*     3.9    23.0    -      -       +      +
    249B  MET*     5.7     1.0    -      -       -      -
    252B  SER*     4.3    11.4    -      -       -      +
    301B  VAL*     2.5    42.5    +      -       +      +
    302B  LEU*     3.1    25.8    -      -       +      +
    304B  LEU*     1.3    88.2    -      -       +      +
    306B  HIS*     1.3    50.9    +      -       -      +
    308B  SER*     4.3     4.9    +      -       -      -
    311B  THR*     4.6     1.9    -      -       -      +
    312B  HIS*     2.6    49.0    +      +       +      +
----------------------------------------------------------
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Residues in contact with HIS 306 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    231A  LEU*     5.5     6.7    -      -       +      -
    234A  TYR*     3.1     3.2    +      -       +      -
    235A  LEU*     2.6    63.0    +      -       +      -
    238A  ASP*     3.0    44.9    +      -       +      +
    239A  SER*     3.5     4.7    -      -       -      -
    242A  LYS*     4.1     4.7    -      -       -      +
    302B  LEU      2.8    15.0    +      -       -      +
    303B  ASN*     3.3    16.1    +      -       -      +
    305B  HIS*     1.3    72.6    -      -       -      +
    307B  ARG*     1.3    55.3    +      -       -      +
    308B  SER      2.4    22.0    +      -       -      +
    312B  HIS      2.4    23.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 307 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238A  ASP*     5.9     2.9    -      -       -      -
    303B  ASN*     3.0    17.2    +      -       -      +
    304B  LEU*     3.8    22.5    +      -       -      +
    305B  HIS      3.5     2.0    -      -       -      -
    306B  HIS*     1.3    77.2    -      -       -      +
    308B  SER*     1.3    76.8    +      -       -      +
    309B  PRO*     3.7     7.8    -      -       -      +
    429B  GLN      3.4    21.2    +      -       -      -
    430B  TYR*     4.1     9.3    -      -       -      +
    431B  VAL*     4.9     2.8    -      -       -      +
    432B  ALA      5.7     1.6    -      -       -      +
    434B  VAL*     2.9    39.8    -      -       -      +
----------------------------------------------------------
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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