Contacts of the helix formed by residues 429 - 452 (chain B) in PDB entry 2CSX


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 LYS 429 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    424B  LEU*     3.3    32.7    +      -       +      +
    425B  ASN*     6.0     0.7    -      -       -      -
    427B  GLU*     3.2    29.8    -      -       +      +
    428B  ARG*     1.3    74.5    -      -       -      +
    430B  LYS*     1.3    62.5    +      -       -      +
    431B  GLU*     3.0     6.2    +      -       -      -
    432B  GLU*     3.1    17.1    +      -       +      -
    433B  LEU*     3.1    10.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 430 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    425B  ASN*     4.3    20.8    +      -       -      +
    428B  ARG*     2.9    67.1    +      -       -      +
    429B  LYS*     1.3    70.2    -      -       -      +
    431B  GLU*     1.3    69.2    +      -       -      +
    433B  LEU*     3.9     8.9    -      -       +      +
    434B  GLN*     3.3    34.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 431 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    373B  ALA*     6.1     0.5    -      -       -      +
    428B  ARG      5.3     0.2    -      -       -      +
    429B  LYS*     3.0     2.4    +      -       -      -
    430B  LYS*     1.3    83.5    +      -       -      +
    432B  GLU*     1.3    66.0    +      -       -      +
    433B  LEU      2.8     6.1    +      -       -      -
    434B  GLN*     3.2    18.5    +      -       -      +
    435B  LYS*     3.7    10.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 432 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    424B  LEU*     3.2    33.9    -      -       +      -
    429B  LYS*     3.1    10.4    +      -       +      +
    431B  GLU*     1.3    78.0    -      -       -      +
    433B  LEU*     1.3    56.4    +      -       -      +
    435B  LYS*     3.8    13.4    -      -       -      +
    436B  VAL*     2.8    36.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 433 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    365B  PHE*     3.8    13.5    -      -       +      -
    366B  LEU*     3.3    27.8    -      -       +      -
    421B  PRO*     3.6    27.4    -      -       +      +
    424B  LEU*     3.5    22.6    -      -       +      +
    425B  ASN*     3.9    21.5    -      -       +      +
    429B  LYS      3.1    12.8    +      -       -      +
    430B  LYS*     3.9    10.1    -      -       +      +
    431B  GLU      2.8     1.8    +      -       -      -
    432B  GLU*     1.3    75.0    -      -       -      +
    434B  GLN*     1.3    53.8    +      -       -      +
    435B  LYS      2.3    19.6    +      -       -      -
    436B  VAL*     3.2    11.1    +      -       +      -
    437B  LEU*     3.2    37.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 434 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    366B  LEU*     4.2    26.0    -      -       +      +
    369B  GLU      5.2     3.6    -      -       -      +
    370B  VAL*     4.7     0.2    -      -       -      -
    371B  SER*     2.4    50.7    +      -       -      +
    372B  GLY*     3.7     9.0    -      -       -      -
    373B  ALA      5.6     0.2    -      -       -      +
    430B  LYS*     3.3    22.6    +      -       +      +
    431B  GLU*     3.2     9.5    +      -       -      +
    433B  LEU*     1.3    74.6    -      -       -      +
    435B  LYS*     1.3    57.0    +      -       -      +
    438B  TYR*     2.8    16.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 435 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    373B  ALA*     2.8    37.1    -      -       +      +
    374B  ARG      3.4    28.9    +      -       -      -
    375B  ASP*     3.7    20.9    +      -       +      +
    377B  GLU*     4.9     8.1    +      -       -      -
    431B  GLU      3.7     7.1    +      -       -      +
    432B  GLU*     3.8    18.4    -      -       -      +
    433B  LEU      2.3    16.6    +      -       -      -
    434B  GLN*     1.3    67.4    -      -       -      +
    436B  VAL*     1.3    53.7    +      -       +      +
    437B  LEU      2.7     5.2    +      -       -      -
    438B  TYR*     2.5    25.9    +      -       -      +
    439B  ALA*     2.7    17.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 436 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    415B  TYR*     3.4    28.5    -      -       +      +
    419B  LYS*     3.3    37.0    -      -       +      +
    421B  PRO*     4.2    11.6    -      -       +      +
    424B  LEU*     3.4    20.6    -      -       +      -
    432B  GLU*     2.8    31.4    -      -       -      +
    433B  LEU*     3.6     7.4    -      -       +      +
    435B  LYS*     1.3    73.5    -      -       -      +
    437B  LEU*     1.3    54.1    +      -       -      +
    439B  ALA*     3.9     1.1    -      -       -      -
    440B  LEU*     2.7    37.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 437 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    358B  VAL*     4.9     7.0    -      -       +      +
    361B  MET*     4.0    33.7    -      -       +      -
    362B  ALA*     4.6     8.2    -      -       +      +
    365B  PHE*     4.1    11.0    -      -       +      -
    366B  LEU*     3.4    30.7    -      -       +      -
    370B  VAL*     3.3    15.5    -      -       +      +
    421B  PRO*     4.0     9.9    -      -       +      -
    433B  LEU*     3.2    37.6    +      -       +      +
    435B  LYS      2.7     4.6    +      -       -      -
    436B  VAL*     1.3    74.3    -      -       -      +
    438B  TYR*     1.3    53.1    +      -       -      +
    439B  ALA      3.1     4.9    -      -       -      -
    440B  LEU*     3.5     9.0    -      -       +      +
    441B  VAL*     2.8    36.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 438 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    370B  VAL*     3.0    19.5    -      -       +      +
    371B  SER*     3.5    17.5    -      -       -      +
    372B  GLY      3.5    26.5    -      -       -      -
    373B  ALA      3.7    10.8    -      -       -      -
    374B  ARG*     4.8     2.0    -      -       +      -
    434B  GLN      2.8    22.4    +      -       -      +
    435B  LYS*     2.5    10.1    +      -       -      +
    437B  LEU*     1.3    72.4    -      -       -      +
    439B  ALA*     1.3    56.1    +      -       -      +
    441B  VAL*     3.6     2.2    -      -       -      -
    442B  ASP*     3.3    19.1    +      -       -      +
    478B  TYR*     3.0    39.6    +      +       -      +
    480B  LYS      2.6    29.2    +      -       -      -
    481B  ASN*     3.1    30.0    -      -       -      +
    483B  TYR*     4.3    16.8    -      +       -      -
----------------------------------------------------------
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Residues in contact with ALA 439 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    375B  ASP*     4.5     5.6    -      -       +      -
    378B  TYR*     3.5    21.7    -      -       +      -
    412B  LEU*     4.5     0.3    -      -       -      +
    415B  TYR*     4.1    20.9    -      -       +      +
    435B  LYS*     2.7    12.2    +      -       +      +
    436B  VAL      4.1     2.9    -      -       -      +
    438B  TYR*     1.3    77.3    -      -       -      +
    440B  LEU*     1.3    61.4    +      -       +      +
    443B  GLY*     2.6    31.2    +      -       -      -
    478B  TYR*     3.4    25.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 440 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    358B  VAL*     3.5    29.2    -      -       +      +
    378B  TYR*     6.4     0.7    -      -       +      -
    412B  LEU*     3.9    24.3    -      -       +      +
    415B  TYR*     3.3    31.9    -      -       +      -
    416B  VAL*     3.2    35.9    -      -       +      -
    421B  PRO*     5.8     2.9    -      -       +      -
    436B  VAL*     2.7    26.9    -      -       +      +
    437B  LEU*     3.1    10.9    +      -       +      +
    439B  ALA*     1.3    80.8    -      -       +      +
    441B  VAL*     1.3    65.7    +      -       -      +
    442B  ASP      3.1     1.3    -      -       -      -
    443B  GLY*     3.0    10.2    +      -       -      -
    444B  LEU*     3.0    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 441 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    358B  VAL*     4.0     4.8    -      -       +      +
    362B  ALA*     5.6     0.2    -      -       +      -
    370B  VAL*     3.7    17.3    -      -       +      -
    437B  LEU      2.8    24.6    +      -       -      +
    438B  TYR*     3.6    14.6    -      -       -      -
    440B  LEU*     1.3    73.9    -      -       -      +
    442B  ASP*     1.3    64.1    +      -       -      +
    444B  LEU*     3.3    14.6    -      -       -      +
    445B  PHE*     3.3    17.7    +      -       -      +
    466B  LEU*     4.2     9.4    -      -       +      +
    483B  TYR*     3.3    33.1    -      -       +      -
    485B  LEU*     3.5    35.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 442 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    378B  TYR*     2.3    30.6    +      -       -      +
    438B  TYR      3.3    18.4    -      -       -      +
    439B  ALA*     3.6     3.1    +      -       -      +
    440B  LEU      3.1     0.6    -      -       -      -
    441B  VAL*     1.3    76.4    -      -       -      +
    443B  GLY*     1.3    63.6    +      -       -      +
    444B  LEU      2.9     6.3    +      -       -      -
    445B  PHE*     2.9    12.3    +      -       -      +
    446B  VAL*     2.9    12.7    +      -       -      +
    477B  PRO*     2.8    34.8    -      -       -      +
    478B  TYR*     3.1    18.7    -      -       +      -
    480B  LYS      4.5     0.2    -      -       -      +
    483B  TYR*     2.7    33.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 443 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    378B  TYR*     3.2    17.2    +      -       -      -
    408B  PHE*     3.6    12.8    -      -       -      -
    412B  LEU*     3.6    21.6    -      -       -      +
    439B  ALA      2.6    21.2    +      -       -      -
    440B  LEU      3.0     5.1    +      -       -      -
    442B  ASP*     1.3    72.7    -      -       -      +
    444B  LEU*     1.3    56.1    +      -       -      +
    446B  VAL*     4.0     0.7    -      -       -      -
    447B  LEU*     3.3    23.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 444 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    354B  LEU*     4.3    17.9    -      -       +      +
    355B  TYR*     3.6    43.0    +      -       +      +
    358B  VAL*     4.0    25.6    -      -       +      -
    359B  VAL*     4.2    15.3    -      -       +      -
    412B  LEU*     6.0     0.9    -      -       +      -
    440B  LEU      3.0    15.0    +      -       -      +
    441B  VAL*     3.3     9.9    -      -       +      +
    442B  ASP      2.9     0.4    -      -       -      -
    443B  GLY*     1.3    76.6    -      -       -      +
    445B  PHE*     1.3    57.6    +      -       -      +
    446B  VAL      3.0     1.3    -      -       -      -
    447B  LEU*     2.8     7.1    +      -       +      +
    448B  THR*     2.6    36.6    +      -       -      +
    466B  LEU*     3.4    31.0    -      -       +      -
    485B  LEU*     5.8     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 445 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    441B  VAL      3.3     7.6    +      -       -      +
    442B  ASP*     2.9     9.1    +      -       -      +
    444B  LEU*     1.3    78.2    -      -       -      +
    446B  VAL*     1.3    58.0    +      -       +      +
    448B  THR*     2.7    14.2    -      -       +      +
    449B  HIS*     2.6    55.5    -      +       -      -
    463B  LEU*     3.9    10.8    -      -       +      -
    466B  LEU*     3.6    17.2    -      -       +      +
    468B  GLU*     3.3    42.8    -      -       +      -
    470B  GLU      4.4    10.5    -      -       -      -
    472B  LEU*     4.2    15.9    -      -       +      -
    479B  SER*     3.4    26.2    -      -       -      -
    480B  LYS*     4.5    10.1    -      -       +      -
    483B  TYR*     3.8    20.2    -      +       +      +
----------------------------------------------------------
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Residues in contact with VAL 446 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    378B  TYR*     4.2     4.3    -      -       -      +
    382B  ALA*     5.0     6.3    -      -       +      +
    385B  SER*     6.2     0.2    -      -       -      -
    386B  ILE*     4.3    22.2    -      -       +      -
    408B  PHE*     3.5    25.6    -      -       +      -
    442B  ASP*     2.9    28.9    +      -       -      +
    443B  GLY      3.9     4.5    -      -       -      +
    445B  PHE*     1.3    79.3    -      -       +      +
    447B  LEU*     1.3    63.7    +      -       -      +
    449B  HIS*     3.3     9.4    +      -       -      +
    450B  LEU*     2.9    36.4    +      -       +      +
    475B  LEU*     4.8     2.6    -      -       +      +
    476B  LYS      4.7     3.8    -      -       -      +
    477B  PRO*     4.2    23.8    -      -       +      +
    479B  SER*     5.8     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 447 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    351B  ILE*     4.5     5.6    -      -       +      -
    354B  LEU*     4.0    17.9    -      -       +      -
    355B  TYR*     3.9    26.0    -      -       +      +
    405B  ILE*     3.6    25.4    -      -       +      +
    408B  PHE*     4.4     4.9    -      -       +      -
    409B  THR*     3.3    37.2    -      -       +      -
    412B  LEU*     5.9     0.4    -      -       +      -
    443B  GLY      3.3    12.2    +      -       -      +
    444B  LEU*     2.8    11.7    +      -       +      +
    446B  VAL*     1.3    79.3    -      -       -      +
    448B  THR*     1.3    62.8    +      -       -      +
    450B  LEU*     3.0    18.4    +      -       +      +
    451B  LEU*     2.9    28.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 448 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355B  TYR*     3.0    21.8    +      -       -      -
    444B  LEU      2.6    18.0    +      -       -      +
    445B  PHE*     2.7    39.0    -      -       +      +
    447B  LEU*     1.3    70.0    -      -       -      +
    449B  HIS*     1.3    60.6    +      -       +      +
    451B  LEU      3.3     0.5    +      -       -      -
    452B  TYR*     2.9    27.2    +      -       -      +
    459B  MET*     3.1    34.2    +      -       -      +
    462B  ALA*     4.0     7.0    -      -       -      +
    463B  LEU*     4.3     6.7    +      -       +      +
    466B  LEU*     3.8    11.7    -      -       +      -
    471B  PHE*     3.8    10.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 449 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  LEU*     4.6     8.4    -      -       +      +
    389B  TYR*     4.4     0.7    +      -       -      -
    445B  PHE*     2.6    55.7    +      +       -      -
    446B  VAL*     3.5     8.1    -      -       -      +
    447B  LEU      3.2     0.6    -      -       -      -
    448B  THR*     1.3    81.5    -      -       +      +
    450B  LEU*     1.3    67.9    +      -       -      +
    451B  LEU      3.0     1.0    +      -       -      -
    452B  TYR*     3.1    16.8    +      -       -      +
    453B  PRO*     3.4    10.0    -      -       -      +
    463B  LEU*     5.1     0.6    -      -       -      +
    471B  PHE*     3.7    21.9    -      +       +      +
    472B  LEU*     2.9    44.9    +      -       +      -
    474B  GLU      4.9     0.9    -      -       -      -
    475B  LEU*     3.7    36.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 450 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    385B  SER*     5.3     3.8    -      -       -      +
    386B  ILE*     4.3    15.7    -      -       +      +
    389B  TYR*     2.6    56.9    +      -       +      -
    404B  GLU      5.8     0.2    -      -       -      +
    405B  ILE*     3.1    27.2    -      -       +      +
    408B  PHE*     3.7    20.2    -      -       +      -
    446B  VAL*     2.9    37.6    +      -       +      +
    447B  LEU*     3.3    15.3    -      -       +      +
    449B  HIS*     1.3    75.9    -      -       -      +
    451B  LEU*     1.3    58.3    +      -       -      +
    453B  PRO*     3.8     1.6    -      -       -      +
    454B  ILE*     4.5     4.0    -      -       -      +
    475B  LEU*     3.5    22.4    -      -       +      -
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Residues in contact with LEU 451 (chain B). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    320B  TYR*     5.0     6.3    -      -       +      -
    347B  LEU*     5.5     0.7    -      -       +      -
    351B  ILE*     3.8    39.7    -      -       +      -
    402B  ILE*     6.1     0.7    -      -       +      -
    405B  ILE*     3.8    29.6    -      -       +      -
    447B  LEU*     2.9    19.8    +      -       +      +
    450B  LEU*     1.3    76.7    -      -       -      +
    452B  TYR*     1.3    64.5    +      -       -      +
    453B  PRO*     3.3     3.4    -      -       -      -
    454B  ILE*     3.1    30.2    +      -       +      +
    455B  THR*     2.9    33.4    +      -       +      +
    459B  MET*     3.6    33.0    -      -       +      -
    492B  PHE*     5.1     2.0    -      -       +      -
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Residues in contact with TYR 452 (chain B). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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     36B  ARG*     2.8    52.2    +      -       +      +
     39B  ARG*     5.8     3.9    -      -       +      +
     40B  LEU*     3.5    28.5    -      -       +      -
     90B  GLU*     4.9     3.6    +      -       -      -
    448B  THR      2.9    15.8    +      -       -      +
    449B  HIS      3.6     7.4    -      -       -      +
    451B  LEU*     1.3    71.8    -      -       -      +
    453B  PRO*     1.3    70.5    -      -       +      +
    456B  PRO*     2.8    57.1    -      -       +      +
    459B  MET*     3.7     9.4    -      -       +      -
    460B  LYS*     4.3    14.9    +      -       -      -
    471B  PHE*     3.4    39.0    -      +       +      -
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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
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  Atomic class           I  II  III   IV   V   VI  VII  VIII
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   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
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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