Contacts of the helix formed by residues 586 - 612 (chain A) in PDB entry 2P6U


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 ALA 586 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  ARG*     4.1     5.8    -      -       -      +
    287A  MET*     3.3    25.8    -      -       +      -
    305A  GLY*     3.6    13.5    -      -       -      -
    580A  CYS*     4.0     3.4    -      -       -      -
    585A  ILE*     1.3    76.4    -      -       -      +
    587A  PRO*     1.3    67.7    -      -       +      -
    588A  GLY      3.1     0.2    -      -       -      -
    589A  ASP*     2.6    41.8    +      -       -      +
    590A  LEU      3.1     4.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with PRO 587 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    283A  ASN*     4.3    27.6    -      -       -      +
    287A  MET*     3.9    22.0    -      -       +      -
    288A  SER*     4.5     0.4    -      -       -      +
    305A  GLY      3.6     8.1    -      -       -      +
    307A  LEU*     3.2    26.5    -      -       +      -
    576A  GLU*     5.1     6.3    -      -       -      +
    580A  CYS*     3.6    22.5    -      -       +      -
    585A  ILE      4.5     0.7    -      -       -      +
    586A  ALA*     1.3    85.6    -      -       +      +
    588A  GLY*     1.3    57.1    +      -       -      +
    590A  LEU*     3.4     4.3    +      -       +      +
    591A  ARG*     2.9    35.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 588 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    304A  ALA      3.8     5.8    -      -       -      -
    305A  GLY      2.7    26.1    +      -       -      -
    306A  LEU      3.2    16.6    -      -       -      -
    307A  LEU*     3.9     4.9    -      -       -      +
    311A  ARG*     5.2     2.6    +      -       -      -
    587A  PRO*     1.3    71.2    -      -       -      +
    589A  ASP*     1.3    56.5    +      -       -      +
    591A  ARG*     3.3     6.8    +      -       -      +
    592A  ARG*     2.8    35.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 589 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  ARG*     2.8    40.0    +      -       -      -
    304A  ALA      3.6     1.9    -      -       -      +
    585A  ILE*     3.8    18.0    -      -       +      +
    586A  ALA      2.6    30.9    +      -       -      +
    588A  GLY*     1.3    67.6    -      -       -      -
    590A  LEU*     1.3    53.5    +      -       -      +
    592A  ARG*     2.6    60.6    +      -       -      +
    593A  ILE*     2.7    26.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 590 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    566A  CYS*     4.8     8.3    -      -       -      -
    570A  TRP*     4.2    15.5    -      -       +      -
    576A  GLU*     4.1    24.5    -      -       +      +
    579A  ILE*     3.8    31.4    -      -       +      -
    580A  CYS*     3.7    21.1    -      -       -      -
    585A  ILE*     3.6    22.1    -      -       +      +
    586A  ALA      3.1     4.9    +      -       -      +
    587A  PRO*     3.6    10.5    -      -       +      +
    589A  ASP*     1.3    80.1    -      -       -      +
    591A  ARG*     1.3    58.3    +      -       +      +
    593A  ILE*     3.2     5.2    +      -       +      +
    594A  VAL*     2.9    55.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 591 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  GLU*     4.2    19.2    +      -       -      +
    283A  ASN*     5.6     1.0    +      -       -      +
    307A  LEU*     3.1    36.1    -      -       +      +
    308A  ASN*     6.0     1.3    -      -       -      +
    570A  TRP*     4.4    13.5    -      -       -      -
    576A  GLU*     2.8    43.6    +      -       -      -
    587A  PRO*     2.9    27.7    +      -       -      +
    588A  GLY*     3.6     5.8    -      -       -      +
    590A  LEU*     1.3    78.4    -      -       +      +
    592A  ARG*     1.3    57.7    -      -       -      +
    594A  VAL*     4.1     5.0    -      -       -      +
    595A  GLU*     2.8    34.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 592 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  ARG*     4.1     4.2    -      -       -      +
    304A  ALA*     3.4    28.8    +      -       -      +
    521A  GLU*     3.2    35.2    +      -       -      +
    588A  GLY      2.8    13.8    +      -       -      +
    589A  ASP*     2.6    67.4    +      -       -      +
    591A  ARG*     1.3    71.6    -      -       -      +
    593A  ILE*     1.3    54.4    +      -       -      +
    595A  GLU*     3.3     6.8    -      -       -      +
    596A  THR*     3.0    35.2    +      -       -      +
    707A  PO4      5.6     6.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 593 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    520A  MET*     3.6    22.1    -      -       +      +
    521A  GLU*     4.0    33.4    -      -       +      +
    522A  ARG      5.3     0.2    -      -       -      +
    523A  LEU*     3.5    32.8    -      -       +      -
    563A  THR*     4.7     4.3    -      -       +      -
    566A  CYS*     5.4     7.6    -      -       -      -
    567A  LEU*     3.8    16.4    -      -       +      -
    585A  ILE*     4.5    12.8    -      -       +      -
    589A  ASP*     2.7    28.3    +      -       +      +
    590A  LEU*     3.6     4.0    -      -       +      +
    592A  ARG*     1.3    69.4    -      -       -      +
    594A  VAL*     1.3    58.4    +      -       +      +
    596A  THR*     3.1     6.3    +      -       -      -
    597A  ALA*     2.7    36.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 594 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    566A  CYS*     6.4     0.2    -      -       -      -
    567A  LEU*     4.4     7.2    -      -       +      -
    570A  TRP*     3.0    53.8    -      -       +      +
    590A  LEU*     2.9    46.0    +      -       +      +
    591A  ARG*     4.1     5.2    -      -       -      +
    593A  ILE*     1.3    73.3    -      -       +      +
    595A  GLU*     1.3    66.1    +      -       -      +
    597A  ALA*     3.6     6.4    -      -       -      +
    598A  GLU*     2.9    24.1    +      -       -      +
    623A  ILE*     3.1    15.9    -      -       +      +
    624A  LYS*     4.6     4.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 595 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    591A  ARG*     2.8    23.3    +      -       -      +
    592A  ARG*     3.3     8.5    -      -       -      +
    594A  VAL*     1.3    79.4    -      -       -      +
    596A  THR*     1.3    63.7    +      -       -      +
    598A  GLU*     3.5    19.9    +      -       -      +
    599A  TRP*     3.5    15.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 596 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    519A  ASP      3.9    11.4    -      -       -      +
    520A  MET*     3.9    12.1    -      -       -      -
    521A  GLU*     4.5     8.7    +      -       +      +
    592A  ARG*     3.0    20.8    +      -       -      +
    593A  ILE*     3.5     6.9    -      -       -      -
    595A  GLU*     1.3    72.7    -      -       -      +
    597A  ALA*     1.3    68.2    +      -       -      +
    598A  GLU      3.0     1.3    -      -       -      -
    599A  TRP*     2.7    35.7    +      -       +      +
    600A  LEU*     3.1    29.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 597 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    514A  ILE*     4.1    11.7    -      -       +      +
    520A  MET*     4.0    14.3    -      -       +      -
    567A  LEU*     3.4    38.4    -      -       +      -
    593A  ILE      2.7    21.3    +      -       -      +
    594A  VAL      3.6     3.1    -      -       -      +
    596A  THR*     1.3    71.7    -      -       -      +
    598A  GLU*     1.3    57.4    +      -       -      +
    600A  LEU*     3.5     3.2    +      -       -      +
    601A  SER*     2.8    28.7    +      -       -      -
    623A  ILE*     4.0     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 598 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    594A  VAL*     2.9    16.4    +      -       +      +
    595A  GLU*     3.5    20.6    -      -       -      +
    596A  THR      2.9     0.6    +      -       -      -
    597A  ALA*     1.3    77.4    -      -       -      +
    599A  TRP*     1.3    53.5    +      -       -      +
    601A  SER*     2.8     9.4    +      -       -      -
    602A  ASN*     2.7    34.3    +      -       +      +
    620A  THR*     3.7    25.4    -      -       +      +
    623A  ILE*     3.8    12.3    -      -       +      +
    624A  LYS*     3.7    42.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 599 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105A  TYR*     4.1    26.4    -      +       -      -
    486A  LEU      3.7    16.2    +      -       -      -
    487A  TYR*     3.4    24.2    -      +       -      -
    488A  ILE*     3.5    14.7    -      -       +      +
    519A  ASP*     3.9    30.1    -      -       +      -
    595A  GLU      3.5     7.8    +      -       -      +
    596A  THR*     2.7    27.9    +      -       +      +
    598A  GLU*     1.3    76.6    -      -       -      +
    600A  LEU*     1.3    83.8    +      -       +      +
    602A  ASN*     3.4     8.8    +      -       +      +
    603A  ALA*     3.1    22.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 600 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    488A  ILE*     4.2     7.9    -      -       +      -
    492A  THR*     4.6     4.7    -      -       +      -
    496A  PHE*     3.8     8.5    -      -       +      -
    514A  ILE*     4.1    11.9    -      -       +      -
    517A  THR*     3.8     7.4    -      -       +      -
    519A  ASP*     3.5    20.4    -      -       +      +
    520A  MET*     3.5    47.1    -      -       +      +
    596A  THR*     3.1    14.7    +      -       +      +
    597A  ALA      3.9     4.7    -      -       -      +
    599A  TRP*     1.3   108.2    -      -       +      +
    601A  SER*     1.3    56.0    +      -       -      +
    603A  ALA*     2.9     5.5    +      -       +      +
    604A  MET*     2.6    38.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 601 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    514A  ILE*     3.9    15.9    -      -       -      +
    597A  ALA      2.8    17.0    +      -       -      -
    598A  GLU*     2.8    17.7    +      -       -      -
    600A  LEU*     1.3    76.5    -      -       -      +
    602A  ASN*     1.3    60.6    +      -       -      +
    604A  MET*     3.5     6.8    +      -       -      +
    605A  ASN*     3.0    20.1    +      -       -      +
    619A  LEU*     3.9    12.1    -      -       -      +
    620A  THR*     3.2    34.5    +      -       -      -
    623A  ILE*     3.8     9.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 602 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    486A  LEU*     5.9     1.0    -      -       -      +
    598A  GLU*     2.7    15.4    +      -       +      +
    599A  TRP*     3.5    11.4    -      -       +      +
    601A  SER*     1.3    74.3    -      -       -      +
    603A  ALA*     1.3    64.8    +      -       -      +
    605A  ASN*     3.1     7.1    +      -       -      +
    606A  ARG*     2.9    34.7    +      -       -      +
    620A  THR*     3.5    20.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 603 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    486A  LEU*     3.7    28.6    -      -       +      +
    488A  ILE*     4.0    24.0    -      -       +      -
    496A  PHE*     4.3     3.8    -      -       +      -
    599A  TRP*     3.1    15.0    +      -       +      +
    600A  LEU*     2.9    12.7    +      -       -      +
    602A  ASN*     1.3    79.8    +      -       -      +
    604A  MET*     1.3    63.7    +      -       -      +
    606A  ARG*     3.3     0.6    +      -       -      -
    607A  ILE*     3.0    29.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 604 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    496A  PHE*     3.5    39.0    -      -       +      -
    500A  LEU*     3.4    14.2    -      -       +      +
    510A  ALA*     4.0    10.8    -      -       +      +
    513A  LEU*     4.2    11.4    -      -       +      -
    514A  ILE*     3.9    24.0    -      -       +      -
    600A  LEU      2.6    19.0    +      -       -      +
    601A  SER*     3.7     9.6    -      -       -      +
    603A  ALA*     1.3    71.5    -      -       -      +
    605A  ASN*     1.3    58.7    +      -       +      +
    607A  ILE*     3.4     1.4    +      -       -      +
    608A  ALA*     2.8    26.5    +      -       -      +
    616A  VAL*     3.1    38.8    -      -       +      -
    619A  LEU*     3.5    23.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 605 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    601A  SER      3.0    14.2    +      -       -      +
    602A  ASN*     3.1     9.4    +      -       -      +
    604A  MET*     1.3    75.6    -      -       +      +
    606A  ARG*     1.3    67.0    +      -       -      +
    608A  ALA*     3.0     6.6    +      -       -      +
    609A  GLU*     2.8    53.6    +      -       -      +
    613A  ASN      5.6     0.9    -      -       -      +
    614A  THR*     5.8     1.0    -      -       -      -
    616A  VAL*     4.0    17.5    -      -       +      +
    617A  SER*     4.0    31.5    +      -       -      +
    620A  THR*     4.4     9.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 606 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  GLU*     2.3    36.1    +      -       -      +
    482A  LEU*     3.2    32.0    -      -       +      +
    485A  ARG*     3.2    24.0    -      -       -      +
    486A  LEU*     4.6     9.2    -      -       +      +
    602A  ASN*     2.9    24.7    +      -       -      +
    603A  ALA      3.9     4.5    -      -       -      +
    605A  ASN*     1.3    78.1    -      -       -      +
    607A  ILE*     1.3    61.8    +      -       -      +
    609A  GLU*     3.5    23.1    +      -       -      +
    610A  GLU*     3.2    19.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 607 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    479A  LEU*     4.9     6.5    -      -       +      -
    482A  LEU*     3.8    21.3    -      -       +      -
    483A  VAL*     5.0     6.7    -      -       +      -
    486A  LEU*     4.0     4.7    -      -       +      -
    488A  ILE*     4.1     9.6    -      -       +      -
    493A  GLY*     3.6    33.7    -      -       -      +
    496A  PHE*     3.8    20.4    -      -       +      -
    497A  HIS*     3.5    39.2    +      -       +      +
    500A  LEU*     4.4     1.8    -      -       +      -
    603A  ALA      3.0    17.5    +      -       -      +
    604A  MET      3.6     4.3    -      -       -      +
    606A  ARG*     1.3    74.0    -      -       -      +
    608A  ALA*     1.3    70.0    +      -       -      +
    610A  GLU*     3.0    15.9    +      -       -      +
    611A  VAL*     3.3     9.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 608 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    500A  LEU*     3.2    28.3    -      -       +      -
    604A  MET      2.8    11.1    +      -       -      +
    605A  ASN*     3.2     9.2    -      -       -      +
    607A  ILE*     1.3    75.5    -      -       -      +
    609A  GLU*     1.3    62.8    +      -       -      +
    611A  VAL*     2.8    13.1    +      -       -      +
    612A  GLY      2.8    19.1    +      -       -      -
    613A  ASN*     3.4    16.3    +      -       +      +
    616A  VAL*     3.7    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 609 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    605A  ASN*     2.8    50.1    +      -       -      +
    606A  ARG*     3.6    25.4    +      -       -      +
    608A  ALA*     1.3    71.2    -      -       +      +
    610A  GLU*     1.3    66.6    +      -       -      +
    612A  GLY*     2.8    17.9    +      -       -      +
    613A  ASN      4.0     7.1    +      -       -      +
    614A  THR*     6.2     2.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 610 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    478A  LYS*     3.5    13.8    -      -       +      +
    479A  LEU*     3.2    42.2    +      -       -      +
    482A  LEU*     4.7     9.7    -      -       +      +
    497A  HIS*     4.0    23.4    +      -       -      -
    606A  ARG      3.2     9.5    +      -       -      +
    607A  ILE*     3.0    13.2    +      -       -      +
    609A  GLU*     1.3    78.2    -      -       -      +
    611A  VAL*     1.3    59.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 611 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    497A  HIS*     4.2    18.2    -      -       +      +
    500A  LEU*     4.5     1.1    -      -       +      -
    501A  SER*     3.2    45.1    -      -       -      +
    607A  ILE*     3.3     4.8    +      -       +      +
    608A  ALA*     2.8    18.3    +      -       -      +
    609A  GLU      3.4     0.2    -      -       -      -
    610A  GLU*     1.3    83.0    +      -       -      +
    612A  GLY*     1.3    60.5    +      -       -      +
    613A  ASN*     3.3    22.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 612 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    608A  ALA      2.8     1.0    +      -       -      -
    609A  GLU*     2.8    14.3    +      -       -      -
    611A  VAL*     1.3    79.6    -      -       -      +
    613A  ASN*     1.3    67.6    +      -       -      +
    614A  THR*     3.6    11.7    +      -       -      +
----------------------------------------------------------
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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