Contacts of the helix formed by residues 281 - 307 (chain L) in PDB entry 4BOG


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 L).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132L  VAL*     6.3     0.7    -      -       +      -
    279L  ILE      4.5     3.4    -      -       -      +
    280L  ILE*     1.3    83.8    -      -       +      +
    282L  SER*     1.3    53.9    +      -       -      +
    283L  TYR      3.3     1.8    -      -       -      -
    284L  LEU*     2.4    55.0    +      -       +      +
    285L  MET*     2.5    58.0    +      -       +      +
    288L  MET*     5.5     3.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 282 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136L  PRO*     6.4     0.7    -      -       -      -
    137L  PHE*     5.4     0.4    -      -       -      -
    280L  ILE*     3.3    17.4    -      -       -      +
    281L  ILE*     1.3    77.7    -      -       -      +
    283L  TYR*     1.3    86.0    +      -       -      -
    285L  MET*     3.1    27.8    +      -       -      +
    286L  PHE*     2.6    31.7    +      -       -      -
    460L  HIS*     3.3    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 283 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135L  PHE*     4.1    42.3    +      +       +      -
    136L  PRO*     5.7     1.3    -      -       +      -
    137L  PHE*     2.7    46.8    -      +       -      -
    221L  ILE*     4.9    25.6    -      -       +      -
    280L  ILE*     5.1     6.1    -      -       +      -
    281L  ILE      2.7     2.4    +      -       -      -
    282L  SER*     1.3    94.4    +      -       -      +
    284L  LEU*     1.3    55.2    +      -       -      +
    286L  PHE*     3.3    16.2    -      +       +      -
    287L  ILE*     2.7    42.7    +      -       +      +
    457L  ASP*     4.7     9.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 284 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    270L  VAL*     3.7    34.8    -      -       +      +
    271L  PRO*     6.3     0.2    -      -       +      -
    274L  SER*     5.5     8.5    -      -       -      +
    281L  ILE*     2.4    33.5    +      -       +      +
    283L  TYR*     1.3    72.2    -      -       -      +
    285L  MET*     1.3    51.2    +      -       -      +
    287L  ILE*     3.2    28.7    -      -       +      -
    288L  MET*     2.5    56.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 285 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    281L  ILE*     2.5    43.4    +      -       +      +
    282L  SER*     3.2    27.1    -      -       -      +
    284L  LEU*     1.3    73.3    -      -       -      +
    286L  PHE*     1.3    63.3    +      -       +      +
    288L  MET*     2.9    12.2    -      -       -      +
    289L  ILE*     2.9    23.3    -      -       +      +
    456L  LEU*     6.0     4.0    -      -       +      -
    460L  HIS*     5.2     7.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 286 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282L  SER*     2.6    37.7    -      -       -      -
    283L  TYR*     3.3    13.5    -      +       -      -
    285L  MET*     1.3    80.0    -      -       +      +
    287L  ILE*     1.3    83.5    +      -       +      +
    288L  MET      2.9     5.8    -      -       -      -
    289L  ILE*     2.7    15.7    +      -       +      +
    290L  LEU*     2.4    50.5    +      -       +      +
    453L  SER*     3.3    15.5    -      -       -      -
    456L  LEU*     4.4    12.8    -      -       +      -
    457L  ASP*     2.7    41.1    -      -       -      -
    460L  HIS*     3.7    21.8    -      +       -      -
----------------------------------------------------------
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Residues in contact with ILE 287 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224L  THR*     6.0     6.7    -      -       +      -
    228L  CYS*     5.1    14.4    -      -       -      -
    270L  VAL*     6.0     3.6    -      -       +      -
    283L  TYR*     2.7    36.2    +      -       +      +
    284L  LEU*     3.2    34.3    -      -       +      -
    286L  PHE*     1.3    96.7    -      -       +      +
    288L  MET*     1.3    57.4    +      -       -      +
    290L  LEU*     3.1    16.3    -      -       +      +
    291L  VAL*     2.4    43.5    +      -       +      +
    457L  ASP*     5.3     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 288 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    216K  VAL*     5.2    14.1    -      -       +      -
    217K  ASN*     5.5    12.3    -      -       +      +
    220K  ILE*     5.8     3.6    -      -       +      -
    281L  ILE*     6.0     2.9    -      -       +      -
    284L  LEU*     2.5    36.3    +      -       +      +
    285L  MET*     2.9    12.6    -      -       -      +
    287L  ILE*     1.3    79.7    -      -       +      +
    289L  ILE*     1.3    60.7    +      -       +      +
    291L  VAL*     2.6    38.1    -      -       +      +
    292L  ALA*     2.9     8.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 289 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285L  MET*     2.9    21.3    -      -       +      +
    286L  PHE*     2.7    17.9    +      -       +      +
    288L  MET*     1.3    82.9    -      -       +      +
    290L  LEU*     1.3    50.2    +      -       +      +
    291L  VAL      3.0     1.6    -      -       -      -
    292L  ALA*     3.1     5.6    +      -       +      +
    293L  PHE*     2.6    86.1    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 290 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228L  CYS*     5.2    14.6    -      -       +      -
    286L  PHE*     2.4    38.5    +      -       +      +
    287L  ILE*     3.1    34.1    -      -       +      +
    289L  ILE*     1.3    72.4    -      -       +      +
    291L  VAL*     1.3    60.8    +      -       -      +
    293L  PHE*     3.3    11.0    -      -       +      +
    294L  SER*     3.0    25.5    +      -       -      -
    449L  ILE*     3.9    24.2    -      -       +      +
    450L  GLY*     4.8     5.2    -      -       -      -
    453L  SER*     2.8    32.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 291 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263L  LEU*     3.3    36.5    -      -       +      +
    287L  ILE*     2.4    31.3    +      -       +      +
    288L  MET*     2.6    28.9    -      -       +      +
    290L  LEU*     1.3    72.4    -      -       -      +
    292L  ALA*     1.3    80.1    +      -       +      +
    293L  PHE      2.9     1.1    +      -       -      -
    294L  SER*     3.1     2.6    +      -       -      -
    295L  VAL*     2.7    46.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 292 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    288L  MET*     2.9    10.7    +      -       +      +
    289L  ILE*     3.4    12.6    -      -       +      +
    291L  VAL*     1.3    85.0    -      -       +      +
    293L  PHE*     1.3    63.6    +      -       +      +
    295L  VAL*     3.4     9.3    -      -       -      +
    296L  ILE*     2.8    39.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 293 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289L  ILE*     2.6    55.5    +      -       +      +
    290L  LEU*     3.3    13.2    -      -       +      +
    291L  VAL      2.9     1.2    -      -       -      -
    292L  ALA*     1.3    79.0    -      -       +      +
    294L  SER*     1.3    52.4    +      -       -      +
    296L  ILE*     4.2     1.7    -      -       +      +
    297L  LEU*     2.7    40.5    +      -       -      +
    445L  THR*     5.8     1.1    -      -       +      -
    449L  ILE*     3.5    56.1    -      -       +      -
    452L  PHE*     6.1     0.4    -      +       -      -
----------------------------------------------------------
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Residues in contact with SER 294 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228L  CYS      5.3     1.4    +      -       -      -
    231L  ILE*     5.4     4.4    -      -       -      +
    232L  SER*     4.8     9.5    +      -       -      -
    235L  ALA*     4.8    11.7    -      -       -      +
    239L  PHE*     5.5     4.6    -      -       -      -
    259L  LEU*     5.2     8.3    -      -       -      +
    263L  LEU*     5.0    15.3    -      -       -      -
    290L  LEU      3.0    17.4    +      -       -      -
    291L  VAL*     3.9     2.9    -      -       -      -
    293L  PHE*     1.3    72.4    -      -       -      +
    295L  VAL*     1.3    58.4    +      -       -      +
    297L  LEU*     4.3     6.1    -      -       -      -
    298L  SER*     2.8    32.7    +      -       -      -
    449L  ILE*     5.3     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 295 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224K  LEU*     5.9     7.4    -      -       +      -
    259L  LEU*     6.4     0.9    -      -       -      -
    260L  THR*     6.0     8.1    -      -       +      +
    263L  LEU*     5.4    12.8    -      -       +      -
    291L  VAL*     2.7    42.3    +      -       +      +
    292L  ALA*     3.4    11.0    -      -       -      +
    294L  SER*     1.3    72.8    -      -       -      +
    296L  ILE*     1.3    68.6    +      -       +      +
    298L  SER*     2.6    22.3    +      -       -      -
    299L  VAL*     2.9    22.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 296 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227K  PHE*     5.8     5.8    -      -       +      -
    292L  ALA*     2.8    23.0    +      -       +      +
    293L  PHE*     4.2     2.0    -      -       +      +
    295L  VAL*     1.3    77.0    -      -       +      +
    297L  LEU*     1.3    59.9    +      -       -      +
    298L  SER      3.2     1.8    -      -       -      -
    299L  VAL*     3.5    13.9    -      -       +      +
    300L  VAL*     2.6    42.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 297 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239L  PHE*     4.9    12.1    -      -       +      -
    293L  PHE      2.7    25.0    +      -       -      +
    294L  SER*     4.1     4.3    -      -       -      +
    296L  ILE*     1.3    75.5    -      -       -      +
    298L  SER*     1.3    59.2    +      -       -      +
    300L  VAL*     3.7     9.9    -      -       +      +
    301L  VAL*     2.8    55.1    +      -       +      +
    441L  TYR*     4.7     9.0    -      -       +      +
    442L  ILE*     3.9    22.0    -      -       +      -
    445L  THR*     3.1    43.7    -      -       +      +
    446L  MET*     5.0     5.4    -      -       +      +
    449L  ILE*     5.3     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 298 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239L  PHE*     4.4    13.0    -      -       -      -
    256L  LEU*     2.8    48.7    -      -       -      +
    259L  LEU*     4.9     6.2    -      -       -      +
    260L  THR*     5.2     3.8    +      -       -      -
    294L  SER      2.8    15.6    +      -       -      -
    295L  VAL*     2.6    23.7    +      -       -      -
    297L  LEU*     1.3    74.1    -      -       -      +
    299L  VAL*     1.3    57.3    +      -       -      +
    301L  VAL*     2.6    29.7    -      -       -      +
    302L  LEU      3.1     3.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 299 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224K  LEU*     5.5    10.5    -      -       +      +
    227K  PHE*     4.2    26.5    -      -       +      -
    228K  LEU*     4.9    10.8    -      -       +      -
    231K  LEU*     4.5    13.1    -      -       +      +
    256L  LEU*     5.0     2.0    -      -       +      -
    260L  THR*     5.6     5.6    -      -       -      +
    295L  VAL*     2.9    30.0    +      -       +      +
    296L  ILE*     3.1    16.7    +      -       +      +
    298L  SER*     1.3    80.7    -      -       -      +
    300L  VAL*     1.3    61.2    +      -       -      +
    302L  LEU*     2.8    17.4    -      -       +      +
    303L  ASN*     2.8    21.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 300 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227K  PHE*     5.6     5.8    -      -       +      -
    296L  ILE*     2.6    31.5    +      -       +      +
    297L  LEU*     3.7    13.9    -      -       +      +
    299L  VAL*     1.3    69.6    -      -       -      +
    301L  VAL*     1.3    61.2    +      -       +      +
    302L  LEU      2.9     1.1    -      -       -      -
    303L  ASN*     2.7    17.8    +      -       +      +
    304L  LEU*     2.4    32.6    +      -       -      +
    441L  TYR*     5.5     9.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 301 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238L  VAL*     5.2     0.9    -      -       +      -
    239L  PHE*     4.3    19.1    -      -       +      -
    256L  LEU*     4.8     1.1    -      -       +      -
    297L  LEU*     2.8    44.1    +      -       +      +
    298L  SER*     2.6    37.7    -      -       -      +
    300L  VAL*     1.3    79.1    -      -       +      +
    302L  LEU*     1.3    52.5    +      -       -      +
    304L  LEU*     2.8    20.1    +      -       +      +
    305L  HIS*     2.5    51.5    +      -       +      +
    442L  ILE*     3.8    17.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 302 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    228K  LEU*     4.2    21.8    -      -       +      -
    231K  LEU*     4.9     7.9    -      -       +      -
    235K  LEU*     5.8     1.9    -      -       +      +
    242K  LYS*     4.3     4.2    +      -       -      +
    252L  SER*     4.9     0.9    -      -       -      +
    253L  ILE*     3.2    51.8    -      -       +      +
    256L  LEU*     3.3    29.8    -      -       +      -
    298L  SER      3.2     6.3    -      -       -      +
    299L  VAL*     2.8    20.2    -      -       +      +
    301L  VAL*     1.3    82.9    -      -       -      +
    303L  ASN*     1.3    55.6    +      -       -      +
    305L  HIS*     3.1    23.0    +      -       +      +
    306L  HIS*     2.8    25.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 303 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    227K  PHE*     2.8    37.2    -      -       +      -
    231K  LEU*     3.6    15.9    -      -       +      +
    299L  VAL      2.8    10.9    +      -       -      +
    300L  VAL*     2.7    22.3    +      -       +      +
    302L  LEU*     1.3    74.5    -      -       -      +
    304L  LEU*     1.3    63.5    +      -       -      +
    305L  HIS      3.1     0.2    -      -       -      -
    306L  HIS*     3.5    14.5    -      -       -      +
    307L  ARG*     3.0    25.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 304 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    242L  PRO*     6.1     3.1    -      -       +      -
    300L  VAL*     2.4    18.5    +      -       +      +
    301L  VAL*     2.9    33.7    -      -       +      +
    303L  ASN*     1.3    71.0    -      -       -      +
    305L  HIS*     1.3    77.5    +      -       +      +
    307L  ARG*     3.8    29.3    +      -       -      +
    434L  VAL*     3.8    33.2    -      -       +      -
    435L  ALA*     4.4    19.1    -      -       +      +
    438L  LEU*     4.2    21.1    -      -       +      -
    442L  ILE*     5.1     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 305 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    242K  LYS*     4.3     2.5    -      -       -      +
    238L  VAL*     4.1    23.2    +      -       +      +
    239L  PHE*     6.0     0.2    -      -       -      -
    242L  PRO*     4.3    16.0    -      -       +      +
    248L  LYS*     3.9    22.8    -      -       +      +
    249L  MET*     5.5     1.2    +      -       -      -
    252L  SER*     4.3    11.0    -      -       -      -
    301L  VAL*     2.5    43.2    +      -       +      +
    302L  LEU*     3.1    26.5    -      -       +      +
    304L  LEU*     1.3    89.7    -      -       +      +
    306L  HIS*     1.3    51.0    +      -       -      +
    308L  SER*     4.3     4.5    +      -       -      -
    311L  THR*     4.6     1.9    -      -       -      +
    312L  HIS*     2.6    49.8    +      +       +      +
----------------------------------------------------------
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Residues in contact with HIS 306 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    231K  LEU*     5.5     6.7    -      -       +      -
    234K  TYR*     3.1     3.4    +      -       +      -
    235K  LEU*     2.6    63.7    +      -       +      -
    238K  ASP*     3.0    44.0    +      -       +      -
    239K  SER*     3.5     4.9    -      -       -      -
    242K  LYS*     4.1     4.9    -      -       -      +
    302L  LEU      2.8    15.2    +      -       -      +
    303L  ASN*     3.3    16.1    +      -       -      +
    305L  HIS*     1.3    72.0    -      -       -      +
    307L  ARG*     1.3    55.6    +      -       -      +
    308L  SER      2.4    21.6    +      -       -      +
    312L  HIS      2.4    23.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 307 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238K  ASP*     5.9     3.6    -      -       -      -
    303L  ASN*     3.0    17.0    +      -       -      +
    304L  LEU*     3.8    23.6    +      -       -      +
    305L  HIS      3.5     2.0    -      -       -      -
    306L  HIS*     1.3    77.7    -      -       -      +
    308L  SER*     1.3    75.6    +      -       -      +
    309L  PRO*     3.7     7.7    -      -       -      +
    429L  GLN      3.4    21.0    +      -       -      -
    430L  TYR*     4.1     8.9    -      -       -      +
    431L  VAL*     4.9     2.6    -      -       -      +
    432L  ALA      5.7     1.8    -      -       -      +
    434L  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