Contacts of the helix formed by residues 409 - 432 (chain B) in PDB entry 1ISS


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 409 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  ARG*     4.0    13.7    -      -       -      +
    185B  TYR*     5.0     5.2    -      -       +      +
    186B  SER*     4.3    23.7    +      -       -      +
    318B  ASP*     5.3     1.6    +      -       -      -
    342B  LEU*     4.1    32.1    -      -       +      +
    344B  SER*     4.4     4.7    -      -       -      -
    407B  ASP*     2.9    17.4    +      -       -      +
    408B  SER*     1.3    92.1    +      -       -      +
    410B  MET*     1.3    66.7    +      -       -      +
    411B  GLY      3.4     1.8    -      -       -      -
    412B  PHE*     3.2    36.8    +      -       +      +
    413B  VAL*     3.4    11.5    +      -       +      +
   2001B  MCG      4.3    26.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 410 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  GLN*     4.4    14.8    -      -       +      +
     78B  ARG*     5.0     4.9    -      -       -      +
     81B  ALA*     4.1    11.2    -      -       +      -
    345B  PRO      5.7     0.4    -      -       -      +
    347B  VAL*     4.2    12.3    -      -       +      -
    350B  PHE*     3.5    47.1    -      -       +      -
    406B  GLN*     4.1    14.4    -      -       +      +
    407B  ASP*     3.1    42.1    +      -       +      +
    408B  SER      3.4     1.2    -      -       -      -
    409B  LYS*     1.3    74.1    -      -       -      +
    411B  GLY*     1.3    56.2    +      -       -      +
    413B  VAL*     2.6    33.0    +      -       +      +
    414B  ILE*     3.1    32.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 411 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    344B  SER*     4.0    11.4    +      -       -      -
    345B  PRO*     4.7     5.6    +      -       -      -
    347B  VAL*     4.3    18.3    -      -       -      +
    409B  LYS      3.4     1.0    +      -       -      -
    410B  MET*     1.3    78.6    -      -       -      +
    412B  PHE*     1.3    63.1    +      -       -      +
    414B  ILE*     3.4     5.0    +      -       -      +
    415B  ASN*     3.0    32.3    +      -       -      -
    462B  VAL*     4.4     6.9    -      -       -      +
    463B  SER*     5.3     3.8    -      -       -      -
    465B  GLU*     5.5     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 412 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185B  TYR*     3.4    26.0    -      -       +      +
    204B  VAL*     3.7    18.2    -      -       +      +
    205B  VAL*     3.3    33.2    -      -       +      -
    206B  PRO*     5.3     2.9    -      -       +      -
    342B  LEU*     3.4    30.3    -      -       +      -
    343B  GLN      3.9    22.9    -      -       -      -
    344B  SER*     4.1    13.6    +      -       -      -
    345B  PRO*     6.1     0.7    -      -       +      -
    409B  LYS*     3.2    28.6    +      -       +      +
    410B  MET      2.9     2.4    +      -       -      -
    411B  GLY*     1.3    75.5    -      -       -      +
    413B  VAL*     1.3    54.1    +      -       -      +
    415B  ASN*     3.1     8.2    +      -       -      +
    416B  ALA*     2.7    35.3    +      -       -      +
    465B  GLU*     5.6     4.7    -      -       -      -
    478B  ARG*     5.6    10.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 413 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51B  PHE*     4.3    20.2    -      -       +      -
     78B  ARG*     3.7    30.5    -      -       -      +
     81B  ALA*     4.8    14.4    -      -       +      -
    160B  ILE*     5.6     0.4    -      -       +      -
    185B  TYR*     3.9    30.3    -      -       +      -
    409B  LYS      3.4    12.1    +      -       -      +
    410B  MET*     2.6    17.9    +      -       +      +
    412B  PHE*     1.3    70.7    -      -       -      +
    414B  ILE*     1.3    67.5    +      -       +      +
    416B  ALA*     2.8    15.1    +      -       -      +
    417B  ILE*     3.1    28.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 414 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81B  ALA*     5.4     2.7    -      -       +      -
     84B  HIS*     5.7     5.2    -      -       +      -
     85B  THR*     3.3    22.7    -      -       -      +
     88B  LYS*     5.4     2.0    -      -       -      +
    347B  VAL*     3.9    27.1    -      -       +      -
    350B  PHE*     4.9     5.4    -      -       +      -
    410B  MET*     3.1    39.7    +      -       +      +
    411B  GLY      3.8     4.0    -      -       -      +
    413B  VAL*     1.3    75.6    -      -       +      +
    415B  ASN*     1.3    57.3    +      -       -      +
    417B  ILE*     3.2    14.8    -      -       -      +
    418B  TYR*     2.8    48.7    +      -       +      +
    462B  VAL*     4.0    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 415 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204B  VAL*     4.4    11.0    -      -       +      -
    411B  GLY      3.0    17.5    +      -       -      +
    412B  PHE*     3.3    14.6    -      -       -      +
    414B  ILE*     1.3    75.4    -      -       -      +
    416B  ALA*     1.3    55.9    +      -       -      +
    417B  ILE      3.0     1.6    -      -       -      -
    418B  TYR*     2.9     7.1    +      -       -      +
    419B  ALA*     2.6    37.4    +      -       -      +
    459B  PHE*     3.7    14.6    -      -       +      -
    461B  GLY*     3.4     8.6    -      -       -      -
    462B  VAL*     3.0    27.8    +      -       -      +
    465B  GLU*     3.3    33.7    +      -       -      +
    467B  VAL*     4.6     5.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 416 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    160B  ILE*     4.0    19.7    -      -       +      +
    183B  ILE*     3.8    20.0    -      -       +      +
    184B  ALA      4.0     7.9    -      -       -      +
    185B  TYR*     4.3     6.7    -      -       +      -
    204B  VAL*     3.5    22.1    -      -       +      +
    412B  PHE      2.7    16.3    +      -       -      +
    413B  VAL      2.8    10.7    +      -       -      +
    415B  ASN*     1.3    71.0    -      -       -      +
    417B  ILE*     1.3    64.5    +      -       -      +
    419B  ALA*     3.4     4.6    +      -       -      +
    420B  MET*     3.2    17.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 417 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  ILE*     5.0    10.5    -      -       +      +
     51B  PHE*     5.7     0.2    -      -       +      -
     81B  ALA      5.1     0.4    -      -       -      -
     82B  MET*     3.6    47.8    -      -       +      +
     85B  THR*     3.6    29.4    -      -       +      +
     86B  LEU*     5.0     2.5    -      -       +      -
     89B  ILE*     4.1    10.1    -      -       +      -
    160B  ILE*     4.4    13.0    -      -       +      -
    413B  VAL*     3.1    29.5    +      -       +      +
    414B  ILE*     3.2    15.7    -      -       -      +
    415B  ASN      3.0     0.4    -      -       -      -
    416B  ALA*     1.3    73.1    -      -       -      +
    418B  TYR*     1.3    58.4    +      -       -      +
    420B  MET*     2.5    37.2    +      -       -      +
    421B  ALA*     3.0     4.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 418 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85B  THR*     4.5     4.7    -      -       +      -
     88B  LYS*     3.1    34.2    +      -       -      +
     89B  ILE*     3.3    34.2    +      -       +      +
     95B  LEU*     4.2    20.6    -      -       +      -
    414B  ILE*     2.8    39.6    +      -       +      +
    415B  ASN*     2.9    11.9    +      -       -      +
    417B  ILE*     1.3    77.4    -      -       -      +
    419B  ALA*     1.3    61.2    +      -       -      +
    421B  ALA*     3.1    13.7    +      -       -      +
    422B  HIS*     3.1    24.1    +      +       +      -
    459B  PHE*     4.1    14.8    -      +       +      -
    462B  VAL*     4.2    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 419 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183B  ILE*     4.2     5.6    -      -       +      -
    204B  VAL*     4.6     3.6    -      -       +      -
    415B  ASN      2.6    18.7    +      -       -      +
    416B  ALA*     3.6    10.1    -      -       -      +
    418B  TYR*     1.3    71.9    -      -       -      +
    420B  MET*     1.3    59.2    +      -       -      +
    422B  HIS*     4.2     2.4    -      -       -      +
    423B  GLY*     3.3     8.1    +      -       -      -
    454B  LEU*     3.2    20.1    -      -       -      +
    457B  SER*     5.1     3.7    -      -       -      -
    459B  PHE*     3.2    27.5    -      -       +      -
    467B  VAL*     5.0     0.2    -      -       +      -
    469B  PHE*     4.0    26.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 420 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  ILE*     3.5    33.7    -      -       +      -
    157B  ALA      4.6     2.2    -      -       -      +
    158B  GLY*     3.1    46.2    -      -       -      +
    159B  VAL      3.6     4.7    -      -       -      +
    160B  ILE*     4.1     9.2    -      -       +      -
    181B  PRO*     4.2     8.3    -      -       +      +
    183B  ILE*     3.7    21.1    -      -       +      -
    416B  ALA      3.2    11.1    +      -       -      +
    417B  ILE*     2.5    21.9    +      -       -      +
    419B  ALA*     1.3    71.7    -      -       -      +
    421B  ALA*     1.3    59.7    +      -       -      +
    423B  GLY*     3.7     1.0    +      -       -      -
    424B  LEU*     3.0    28.2    +      -       +      +
    450B  LEU*     4.9     6.5    -      -       -      -
    454B  LEU*     4.2    13.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 421 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  ILE*     5.0     0.8    -      -       -      +
     89B  ILE*     4.4     9.6    -      -       +      -
     95B  LEU*     3.9    22.7    -      -       +      -
     96B  LEU*     4.2     7.5    -      -       +      +
    101B  LEU*     4.2    19.7    -      -       +      -
    417B  ILE      3.0     7.9    +      -       -      +
    418B  TYR      3.5     9.0    -      -       -      +
    420B  MET*     1.3    74.3    -      -       -      +
    422B  HIS*     1.3    53.7    +      -       -      +
    423B  GLY      3.0     1.3    -      -       -      -
    424B  LEU*     2.7    35.7    +      -       -      +
    425B  GLN*     2.8    18.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 422 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95B  LEU*     4.2    28.8    -      -       +      +
    418B  TYR*     3.1    25.9    +      +       +      +
    419B  ALA      4.3     3.1    -      -       -      +
    421B  ALA*     1.3    75.9    -      -       -      +
    423B  GLY*     1.3    66.4    +      -       -      +
    425B  GLN*     3.8    12.8    -      -       +      +
    426B  ASN*     2.9    27.7    +      -       -      +
    457B  SER*     3.8    12.0    +      -       -      -
    458B  SER      4.5     5.4    +      -       -      +
    459B  PHE*     3.4    47.9    -      +       +      +
    460B  VAL      5.6     0.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 423 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    419B  ALA      3.3     7.9    +      -       -      -
    420B  MET      3.7     0.4    +      -       -      -
    421B  ALA      3.0     1.6    +      -       -      -
    422B  HIS*     1.3    79.4    -      -       -      +
    424B  LEU*     1.3    57.5    +      -       -      +
    426B  ASN*     3.6     0.5    +      -       -      +
    427B  MET*     3.0    22.0    +      -       -      +
    450B  LEU*     3.9     6.7    -      -       -      -
    453B  PHE*     3.4    13.3    -      -       -      +
    454B  LEU*     3.4    31.0    -      -       -      -
    457B  SER*     3.6    12.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 424 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  VAL*     3.8    35.4    -      -       +      -
     47B  ILE*     4.6     7.0    -      -       +      -
     96B  LEU*     4.4    13.2    -      -       +      -
    101B  LEU*     4.1    14.6    -      -       +      -
    157B  ALA*     4.7     2.2    -      -       +      -
    420B  MET*     3.0    23.8    -      -       +      +
    421B  ALA*     2.7    18.5    +      -       -      +
    423B  GLY*     1.3    69.0    -      -       -      +
    425B  GLN*     1.3    67.4    +      -       -      +
    427B  MET*     2.7    18.0    +      -       -      +
    428B  HIS*     2.7    16.3    +      -       -      +
    442B  MET*     4.6    11.3    -      -       +      +
    445B  ILE*     4.1    17.0    -      -       +      -
    450B  LEU*     4.3    22.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 425 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94B  VAL*     3.2    15.9    -      -       -      +
     95B  LEU*     3.5    27.1    -      -       +      -
     96B  LEU*     3.0    39.9    +      -       +      +
     97B  PRO*     3.9     7.0    -      -       -      +
    421B  ALA      2.8    12.3    +      -       -      +
    422B  HIS*     3.8    11.2    -      -       +      +
    424B  LEU*     1.3    75.9    -      -       -      +
    426B  ASN*     1.3    62.7    +      -       -      +
    428B  HIS*     3.2     7.4    +      -       -      +
    429B  HIS*     2.8    59.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 426 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    422B  HIS      2.9    19.3    +      -       -      +
    423B  GLY      3.9     2.9    -      -       -      +
    425B  GLN*     1.3    79.3    -      -       +      +
    427B  MET*     1.3    61.3    +      -       -      +
    429B  HIS*     3.8    11.0    +      -       -      +
    430B  ALA*     3.5    12.6    +      -       -      +
    453B  PHE*     3.3    23.0    -      -       +      +
    456B  LYS      6.0     0.7    -      -       -      +
    457B  SER*     4.3    11.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 427 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    423B  GLY      3.0    12.1    +      -       -      +
    424B  LEU*     2.7    18.0    +      -       -      +
    426B  ASN*     1.3    70.3    -      -       -      +
    428B  HIS*     1.3    65.1    +      -       -      +
    430B  ALA*     3.3     2.4    +      -       -      +
    431B  LEU*     3.0    45.5    +      -       +      +
    441B  ALA      4.9     2.9    -      -       -      +
    442B  MET*     3.8    34.1    -      -       +      -
    445B  ILE*     4.0     8.7    -      -       +      -
    446B  ASP*     3.9    31.9    -      -       +      +
    449B  LYS*     4.3     7.2    -      -       +      -
    450B  LEU*     4.0    25.1    -      -       +      -
    453B  PHE*     3.4    27.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 428 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96B  LEU*     5.2     1.3    -      -       +      -
     97B  PRO*     6.0     4.9    -      -       +      +
     99B  ILE*     3.8    21.2    -      -       +      +
    424B  LEU      2.7    15.0    +      -       -      +
    425B  GLN*     3.4    15.5    +      -       -      +
    427B  MET*     1.3    73.1    -      -       -      +
    429B  HIS*     1.3    80.7    +      +       -      +
    430B  ALA      2.9     0.5    +      -       -      -
    432B  CYS*     2.8    52.6    +      -       +      +
    435B  HIS      3.4    22.5    +      -       -      -
    436B  VAL      3.8     9.0    +      -       -      -
    437B  GLY      2.7    29.4    +      -       -      -
    438B  LEU*     4.8     0.7    -      -       -      -
    442B  MET*     3.8    17.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 429 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97B  PRO*     5.6     2.0    -      -       -      +
    425B  GLN*     2.8    54.7    +      -       +      +
    426B  ASN*     4.0     9.2    -      -       -      +
    428B  HIS*     1.3    88.9    -      +       -      +
    430B  ALA*     1.3    62.7    +      -       -      +
    432B  CYS      5.3     1.6    -      -       -      -
    433B  PRO*     4.0    17.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 430 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    426B  ASN      3.5     2.9    +      -       -      +
    427B  MET      3.3     1.2    +      -       -      -
    428B  HIS      2.9     1.6    +      -       -      -
    429B  HIS*     1.3    82.8    -      -       -      +
    431B  LEU*     1.3    64.5    +      -       +      +
    432B  CYS      3.7     0.7    +      -       -      -
    433B  PRO*     3.7     9.2    -      -       -      +
    453B  PHE*     3.6    34.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 431 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    427B  MET*     3.0    47.6    +      -       +      +
    430B  ALA*     1.3    79.7    -      -       +      +
    432B  CYS*     1.3    62.0    +      -       -      +
    433B  PRO*     3.5     6.5    -      -       -      +
    439B  CYS*     2.8    18.7    -      -       -      -
    441B  ALA*     3.5    24.3    -      -       +      +
    442B  MET*     4.9     2.5    -      -       +      -
    449B  LYS*     4.3    29.2    -      -       +      +
    453B  PHE*     4.5    12.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 432 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    428B  HIS*     2.8    45.3    +      -       +      +
    429B  HIS*     4.4     0.7    -      -       -      -
    431B  LEU*     1.3    77.1    -      -       -      +
    433B  PRO*     1.3    71.1    -      -       -      +
    434B  GLY      3.3     0.5    +      -       -      -
    435B  HIS*     3.1    21.5    +      -       +      +
    439B  CYS*     2.0    59.7    -      -       +      -
    442B  MET*     4.1    19.5    -      -       -      -
----------------------------------------------------------
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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