Contacts of the helix formed by residues 432 - 455 (chain B) in PDB entry 1XSK


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 ASP 432 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  ASN*     4.3    13.6    -      -       +      +
     79B  GLY      2.8    16.7    +      -       -      +
    214B  GLN*     5.3     1.2    +      -       -      -
    431B  SER*     1.3    73.4    -      -       -      +
    433B  PRO*     1.3    76.6    -      -       -      +
    434B  GLN*     3.2    21.6    +      -       -      +
    435B  LYS*     3.0    49.4    +      -       +      +
    436B  MET*     3.0    21.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 433 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    422B  PRO      5.1     1.2    -      -       -      +
    423B  THR*     3.1    47.9    -      -       -      +
    425B  VAL*     3.9    16.2    -      -       +      +
    426B  GLN*     5.5     1.1    -      -       -      -
    427B  TRP*     3.9    19.7    +      -       +      +
    431B  SER      3.5     8.5    -      -       -      +
    432B  ASP*     1.3    90.3    -      -       -      +
    434B  GLN*     1.3    62.8    +      -       +      +
    435B  LYS      3.2     1.0    +      -       -      -
    436B  MET*     3.2     1.7    +      -       -      +
    437B  HIS      3.2    19.2    +      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
    182B  TRP*     3.7    30.0    -      -       -      -
    213B  PRO      4.4     0.3    -      -       -      +
    214B  GLN*     3.1    33.2    -      -       +      +
    215B  CYS*     5.9     0.5    -      -       -      +
    423B  THR*     3.5    32.7    +      -       -      +
    432B  ASP*     3.2    18.7    +      -       -      +
    433B  PRO*     1.3    78.9    -      -       +      +
    435B  LYS*     1.3    58.3    +      -       -      +
    437B  HIS*     4.3     2.7    -      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     77B  ASN*     4.3     8.5    +      -       -      +
     78B  ASN      2.8    39.4    +      -       -      +
     79B  GLY      4.1     1.3    -      -       -      +
     80B  PRO*     3.4    28.7    -      -       +      +
     81B  HIS*     4.7     8.3    -      -       -      +
    213B  PRO*     3.8    19.4    -      -       +      +
    214B  GLN*     4.0    39.4    -      -       -      +
    236B  TYR*     5.2     8.5    -      -       -      -
    432B  ASP*     3.0    34.7    +      -       -      +
    434B  GLN*     1.3    77.3    -      -       -      +
    436B  MET*     1.3    65.7    +      -       -      +
    437B  HIS      3.2     2.3    +      -       -      -
    438B  ASN      3.8     2.4    +      -       -      -
    439B  HIS*     3.4    20.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 436 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80B  PRO*     4.0    18.6    -      -       +      -
    389B  PHE*     6.0     1.3    -      -       +      -
    390B  THR*     3.6    15.9    -      -       +      -
    421B  ILE*     4.9     1.6    -      -       -      -
    427B  TRP*     3.5    60.6    -      -       +      +
    431B  SER*     3.5    32.1    -      -       -      -
    432B  ASP      3.0     8.8    +      -       -      +
    433B  PRO      3.2     2.2    +      -       -      +
    435B  LYS*     1.3    76.4    -      -       -      +
    437B  HIS*     1.3    66.9    +      -       -      +
    439B  HIS*     4.3     9.0    -      -       -      -
    440B  TYR*     2.8    44.6    +      -       +      +
    443B  ILE*     5.2     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 437 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182B  TRP*     3.3    61.6    +      +       +      -
    183B  ASN*     2.7    27.9    +      -       +      +
    418B  GLY      4.8     1.4    -      -       -      +
    419B  GLU      3.1    23.5    +      -       -      +
    420B  ARG*     4.5     2.5    -      -       -      -
    421B  ILE*     2.7    47.2    +      -       +      +
    423B  THR*     4.6     2.0    -      -       +      -
    433B  PRO      3.2    12.0    +      -       -      +
    434B  GLN      4.3     1.3    -      -       -      +
    435B  LYS      3.2     0.6    -      -       -      -
    436B  MET*     1.3    79.1    -      -       -      +
    438B  ASN*     1.3    74.0    +      -       -      +
    440B  TYR*     3.8    10.7    -      -       -      +
    441B  ALA      4.7     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 438 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  TYR*     5.1     4.3    +      -       -      +
    181B  THR*     2.8    28.6    +      -       -      -
    182B  TRP*     4.1     4.2    -      -       -      +
    183B  ASN*     2.8    45.5    +      -       -      +
    196B  ASN*     5.2     6.0    -      -       -      +
    213B  PRO*     2.9    29.0    +      -       +      +
    214B  GLN*     3.8     4.6    +      -       -      +
    435B  LYS      3.8     2.2    +      -       -      -
    436B  MET      3.4     0.2    -      -       -      -
    437B  HIS*     1.3    84.1    -      -       -      +
    439B  HIS*     1.3    65.4    +      -       -      +
    440B  TYR      3.1     3.5    +      -       -      -
    441B  ALA      3.4     8.0    +      -       -      -
    469B  SER*     3.1    28.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 439 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80B  PRO*     3.3    36.6    -      -       +      +
     81B  HIS      4.1    16.9    +      -       -      -
     82B  TYR*     4.9     8.9    -      -       +      -
     83B  PRO*     4.5     9.6    -      -       +      +
    213B  PRO*     5.0     6.4    -      -       +      +
    435B  LYS      3.4    17.4    +      -       -      +
    436B  MET*     3.3     8.6    +      -       -      +
    438B  ASN*     1.3    76.8    -      -       -      +
    440B  TYR*     1.3    64.5    +      -       -      +
    441B  ALA      3.3     0.2    -      -       -      -
    442B  TYR*     3.1    37.7    +      +       -      +
    443B  ILE*     3.1    49.7    +      -       +      +
    469B  SER*     4.0     8.7    +      -       -      -
    470B  VAL      5.4     0.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 440 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348B  PRO*     3.3    38.9    +      -       +      +
    386B  ILE*     3.5    12.6    -      -       +      +
    387B  TYR      2.8    28.0    +      -       -      -
    389B  PHE*     3.4    26.0    -      +       +      -
    418B  GLY*     3.7    11.2    -      -       -      -
    421B  ILE*     3.5    34.1    -      -       +      -
    427B  TRP*     3.6    33.0    -      +       -      -
    436B  MET*     2.8    27.1    +      -       +      +
    437B  HIS      3.8     2.5    -      -       -      +
    438B  ASN      3.1     0.4    -      -       -      -
    439B  HIS*     1.3    76.5    -      -       -      +
    441B  ALA*     1.3    64.3    +      -       -      +
    442B  TYR      3.1     0.3    +      -       -      -
    443B  ILE*     3.1     4.4    +      -       +      +
    444B  TYR*     2.8    31.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 441 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183B  ASN*     4.0     5.6    -      -       -      +
    418B  GLY      4.3     7.4    +      -       -      +
    437B  HIS      4.7     0.2    +      -       -      -
    438B  ASN      3.4    11.9    +      -       -      +
    439B  HIS      3.3     0.4    -      -       -      -
    440B  TYR*     1.3    79.0    -      -       -      +
    442B  TYR*     1.3    62.9    +      -       -      +
    444B  TYR*     3.5     5.7    -      -       -      +
    445B  ASN*     2.9    31.7    +      -       -      -
    467B  SER*     3.4    28.3    -      -       -      +
    468B  ALA*     3.7    27.1    -      -       -      +
    469B  SER      5.2     0.7    -      -       -      -
    472B  ALA*     5.6     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 442 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83B  PRO*     3.8    21.5    -      -       +      +
    438B  ASN      4.2     0.8    +      -       -      -
    439B  HIS*     3.1    39.8    +      +       -      +
    440B  TYR      3.1     0.6    -      -       -      -
    441B  ALA*     1.3    77.2    -      -       -      +
    443B  ILE*     1.3    67.4    +      -       +      +
    446B  GLU*     2.9    64.0    +      -       -      +
    469B  SER*     4.0    14.0    -      -       -      +
    470B  VAL      3.6    15.0    -      -       -      +
    471B  GLY      3.5    29.6    -      -       -      -
    472B  ALA*     3.7    10.1    -      -       -      -
    474B  LYS*     2.8    23.7    +      -       -      -
    475B  PHE*     3.7    17.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with ILE 443 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    389B  PHE*     3.9    34.5    -      -       +      +
    390B  THR*     6.0     0.9    -      -       +      -
    395B  CYS*     5.5     2.5    -      -       -      -
    436B  MET*     5.2    10.1    -      -       +      -
    439B  HIS*     3.1    46.7    +      -       +      +
    440B  TYR*     3.8     7.6    -      -       +      +
    442B  TYR*     1.3    86.7    -      -       +      +
    444B  TYR*     1.3    64.9    +      -       -      +
    446B  GLU*     3.9    13.7    -      -       -      +
    447B  LEU*     3.2    22.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 444 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    346B  ILE*     3.5     1.0    +      -       +      -
    347B  ASN*     3.1    15.8    +      -       -      -
    348B  PRO*     3.5    21.5    -      -       +      -
    389B  PHE*     3.8    31.1    -      +       +      -
    398B  TYR*     3.9    18.6    -      -       -      -
    415B  THR*     3.3    36.5    -      -       +      +
    416B  ASP      2.8    28.1    +      -       -      -
    417B  PHE      3.6    14.4    -      -       -      -
    418B  GLY*     4.3     6.5    -      -       -      -
    440B  TYR*     2.8    21.0    +      +       +      +
    441B  ALA*     3.5     3.6    -      -       -      +
    443B  ILE*     1.3    79.6    -      -       -      +
    445B  ASN*     1.3    71.9    +      -       -      +
    447B  LEU*     3.2    10.6    +      -       -      +
    448B  VAL*     3.3    17.5    +      -       +      +
    467B  SER*     4.5     2.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 445 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    415B  THR*     2.7    35.5    +      -       -      +
    441B  ALA      2.9    23.7    +      -       -      +
    442B  TYR*     4.2     1.1    -      -       -      +
    444B  TYR*     1.3    85.2    -      -       -      +
    446B  GLU*     1.3    67.9    +      -       -      +
    448B  VAL*     3.2     7.3    +      -       -      +
    449B  TRP*     2.8    25.1    +      -       -      +
    463B  LEU*     3.8     9.5    -      -       +      +
    465B  ALA*     3.3    12.1    -      -       -      +
    467B  SER*     3.4    24.9    +      -       -      -
    468B  ALA*     5.2     1.0    -      -       -      +
    472B  ALA*     5.5     3.5    -      -       +      +
    475B  PHE*     3.9    19.7    -      -       +      -
    478B  HIS*     5.5     1.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 446 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    442B  TYR*     2.9    50.1    +      -       +      +
    443B  ILE*     3.9    16.4    -      -       -      +
    444B  TYR      3.3     0.2    -      -       -      -
    445B  ASN*     1.3    76.1    -      -       -      +
    447B  LEU*     1.3    55.0    +      -       -      +
    449B  TRP*     3.2     0.7    +      -       -      +
    450B  ASN*     2.8    56.1    +      -       -      +
    474B  LYS*     5.0     0.5    +      -       -      -
    475B  PHE*     3.6    26.5    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
    389B  PHE*     3.8    24.5    -      -       +      -
    395B  CYS*     3.8    43.5    -      -       +      +
    398B  TYR*     3.8    23.6    -      -       +      -
    399B  ALA*     4.2    14.6    -      -       +      -
    402B  LEU*     4.2     6.5    -      -       +      -
    443B  ILE*     3.2    12.6    +      -       +      +
    444B  TYR      3.4     9.0    -      -       -      +
    446B  GLU*     1.3    81.3    -      -       -      +
    448B  VAL*     1.3    70.7    +      -       +      +
    450B  ASN*     3.3     7.5    +      -       -      +
    451B  VAL*     3.3    18.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 448 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    346B  ILE*     4.1    13.7    -      -       +      -
    398B  TYR*     4.4     2.7    -      -       +      -
    402B  LEU*     3.9    22.4    -      -       +      -
    413B  PHE*     3.6    29.4    -      -       +      -
    415B  THR*     3.9    20.2    -      -       +      -
    444B  TYR*     3.5    22.9    -      -       +      +
    445B  ASN      3.2     5.1    +      -       -      +
    447B  LEU*     1.3    81.1    -      -       +      +
    449B  TRP*     1.3    63.9    +      -       -      +
    451B  VAL*     2.9    14.4    +      -       -      +
    452B  LEU*     3.0    17.0    +      -       -      +
    463B  LEU*     3.6    15.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 449 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    262B  ALA*     3.7    18.6    -      -       +      -
    263B  LEU      6.0     0.4    -      -       -      -
    445B  ASN      2.8    20.8    +      -       -      +
    446B  GLU      3.4     3.6    -      -       -      +
    448B  VAL*     1.3    72.9    -      -       -      +
    450B  ASN*     1.3    71.1    +      -       -      +
    451B  VAL      3.1     0.7    +      -       -      -
    452B  LEU*     3.1     9.9    +      -       -      +
    453B  LYS*     2.9    43.5    +      -       +      +
    458B  GLU*     4.7    15.2    -      -       +      +
    461B  ALA*     3.5    42.2    -      -       +      -
    462B  VAL*     3.9     5.8    -      -       -      -
    463B  LEU*     4.1    14.1    -      -       +      +
    474B  LYS      3.9     5.6    +      -       -      -
    475B  PHE*     3.5    40.2    -      +       +      -
    476B  PRO*     3.3    36.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 450 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    446B  GLU*     2.8    38.6    +      -       -      +
    447B  LEU*     3.6     7.8    -      -       -      +
    448B  VAL      3.3     0.2    -      -       -      -
    449B  TRP*     1.3    84.8    -      -       -      +
    451B  VAL*     1.3    56.8    +      -       +      +
    453B  LYS*     3.8    27.9    +      -       -      +
    454B  ASP*     2.6    41.9    +      -       -      +
    475B  PHE*     5.3     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 451 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    399B  ALA*     3.8    32.5    -      -       +      +
    402B  LEU*     4.1    24.0    -      -       +      -
    403B  LYS*     3.6    35.0    -      -       +      +
    406B  VAL*     4.6     5.8    -      -       +      -
    413B  PHE*     5.1     1.8    -      -       +      -
    447B  LEU      3.3    15.2    +      -       -      +
    448B  VAL*     2.9    10.3    +      -       -      +
    450B  ASN*     1.3    76.8    -      -       -      +
    452B  LEU*     1.3    64.5    +      -       +      +
    454B  ASP*     3.2     4.6    +      -       -      +
    455B  THR*     2.8    33.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 452 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    406B  VAL*     4.2    11.4    -      -       +      -
    411B  ASP      3.4    26.0    -      -       -      +
    412B  CYS*     4.3     0.2    -      -       -      -
    413B  PHE*     3.6    38.4    -      -       +      -
    448B  VAL      3.0    31.1    +      -       -      +
    449B  TRP*     3.1     5.2    +      -       -      +
    451B  VAL*     1.3    78.3    -      -       -      +
    453B  LYS*     1.3    63.9    +      -       -      +
    455B  THR*     3.0     3.9    +      -       -      -
    456B  VAL*     2.9    40.4    +      -       +      +
    457B  GLY      3.0     1.9    +      -       -      -
    461B  ALA*     3.6    24.7    -      -       +      -
    462B  VAL      4.5     7.6    -      -       -      +
    463B  LEU*     3.8    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 453 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    449B  TRP*     2.9    35.3    +      -       +      +
    450B  ASN*     3.6    30.9    +      -       -      +
    452B  LEU*     1.3    77.0    -      -       -      +
    454B  ASP*     1.3    71.5    +      -       -      +
    457B  GLY*     3.2    21.6    -      -       -      -
    458B  GLU*     3.4    47.3    +      -       +      +
    461B  ALA*     4.2     1.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 454 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    403B  LYS*     5.6     9.6    +      -       -      +
    450B  ASN*     2.6    26.9    +      -       -      +
    451B  VAL*     4.0     4.7    -      -       -      +
    452B  LEU      3.2     0.2    -      -       -      -
    453B  LYS*     1.3    91.2    -      -       -      +
    455B  THR*     1.3    65.3    +      -       +      +
    457B  GLY*     5.2     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 455 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    403B  LYS*     4.1    29.4    -      -       +      +
    406B  VAL*     3.4    31.2    -      -       +      +
    451B  VAL*     2.8    25.3    +      -       +      +
    452B  LEU*     3.0     9.1    +      -       -      -
    454B  ASP*     1.3    83.9    -      -       +      +
    456B  VAL*     1.3    70.7    +      -       -      +
    457B  GLY*     3.1     4.1    +      -       -      -
----------------------------------------------------------
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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