Contacts of the helix formed by residues 619 - 646 (chain A) in PDB entry 4MXP


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 THR 619 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    568A  LYS*     4.1     0.2    -      -       -      +
    604A  LEU      2.7    26.5    +      -       -      +
    605A  ALA*     3.5    19.6    +      -       -      +
    606A  LYS      3.9     0.9    -      -       -      +
    607A  GLY*     3.9    11.4    -      -       -      +
    612A  THR*     4.0     7.9    -      -       +      -
    617A  LEU      3.5     0.2    +      -       -      -
    618A  LYS*     1.3    79.1    -      -       -      +
    620A  SER*     1.3    65.1    +      -       -      +
    622A  VAL*     3.2    20.3    +      -       -      +
    623A  SER*     3.2    22.2    +      -       -      -
    701A  DB4      3.3    35.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 620 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    532A  TYR*     3.9     9.9    -      -       -      -
    533A  LYS      6.1     0.2    -      -       -      -
    534A  TYR*     3.4    19.4    +      -       -      -
    618A  LYS      3.9     0.4    +      -       -      -
    619A  THR*     1.3    72.9    -      -       -      +
    621A  SER*     1.3    57.4    +      -       -      +
    623A  SER*     3.1    10.0    +      -       -      -
    624A  SER*     2.9    29.5    +      -       -      -
    701A  DB4      2.7    38.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 621 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    532A  TYR*     3.8    14.1    -      -       -      -
    568A  LYS*     3.5     9.8    -      -       -      +
    572A  LEU*     3.6    20.4    -      -       -      +
    604A  LEU*     3.1    38.1    +      -       -      +
    620A  SER*     1.3    71.2    -      -       -      +
    622A  VAL*     1.3    63.4    +      -       -      +
    624A  SER*     3.2     9.8    +      -       -      -
    625A  PHE*     2.9    20.3    +      -       -      +
    701A  DB4      2.7    27.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 622 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    601A  TYR*     3.6    24.2    -      -       +      +
    604A  LEU*     4.0     5.4    -      -       +      -
    605A  ALA*     3.5    34.1    -      -       +      +
    618A  LYS*     3.6    19.5    -      -       +      -
    619A  THR*     3.2    23.0    +      -       -      +
    621A  SER*     1.3    78.0    +      -       -      +
    623A  SER*     1.3    57.9    +      -       -      +
    625A  PHE*     3.3     7.7    +      -       -      +
    626A  GLU*     3.0    49.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 623 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    618A  LYS*     3.4    21.1    +      -       -      +
    619A  THR      3.2    10.1    +      -       -      -
    620A  SER*     3.1    13.4    +      -       -      -
    622A  VAL*     1.3    76.9    -      -       -      +
    624A  SER*     1.3    56.5    +      -       -      +
    626A  GLU*     3.4    10.5    +      -       -      +
    627A  LYS*     2.9    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 624 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    530A  LEU      3.6    13.0    -      -       -      -
    531A  SER*     2.7    29.3    +      -       -      -
    532A  TYR*     3.4    15.4    -      -       -      +
    572A  LEU*     4.0    12.6    -      -       -      -
    620A  SER      2.9    14.9    +      -       -      -
    621A  SER      3.2     8.0    +      -       -      -
    623A  SER*     1.3    77.1    -      -       -      +
    625A  PHE*     1.3    63.0    +      -       -      +
    627A  LYS*     3.2     8.1    +      -       -      +
    628A  MET*     3.0    27.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 625 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    572A  LEU*     3.9     8.0    -      -       +      +
    575A  PHE*     3.8    25.6    -      +       +      -
    579A  LEU*     4.1    11.7    -      -       +      -
    592A  VAL*     4.2    14.1    -      -       +      -
    595A  LEU*     3.8    37.7    -      -       +      -
    596A  LYS*     4.0    23.8    -      -       +      -
    601A  TYR*     3.8    18.8    -      +       -      -
    604A  LEU*     4.6     4.0    -      -       +      -
    621A  SER      2.9    12.5    +      -       -      +
    622A  VAL*     3.5    10.1    -      -       -      +
    624A  SER*     1.3    76.2    -      -       -      +
    626A  GLU*     1.3    65.5    +      -       +      +
    628A  MET*     3.1    12.4    +      -       +      +
    629A  VAL*     2.9    56.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 626 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    596A  LYS*     5.3     5.6    +      -       -      +
    601A  TYR*     4.6     4.8    +      -       -      +
    618A  LYS*     2.8    38.8    +      -       -      +
    622A  VAL*     3.0    33.0    +      -       +      +
    623A  SER*     3.7     6.9    -      -       -      +
    625A  PHE*     1.3    82.8    -      -       +      +
    627A  LYS*     1.3    57.8    +      -       -      +
    629A  VAL*     3.3     8.3    +      -       -      +
    630A  GLU*     2.9    36.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 627 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    503A  LYS*     5.2    10.3    -      -       -      +
    531A  SER*     3.0    33.0    +      -       -      +
    623A  SER      2.9    14.6    +      -       -      +
    624A  SER*     3.2    10.7    +      -       -      +
    626A  GLU*     1.3    77.7    -      -       -      +
    628A  MET*     1.3    57.3    +      -       -      +
    630A  GLU*     3.4     4.9    +      -       -      +
    631A  GLU*     2.9    64.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 628 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    530A  LEU*     4.1    19.7    -      -       -      +
    531A  SER*     4.6     9.2    -      -       -      +
    572A  LEU*     4.0    29.2    -      -       +      +
    575A  PHE*     5.0     0.2    -      -       +      -
    576A  LYS*     3.6    51.1    -      -       +      +
    579A  LEU*     3.8    13.7    -      -       +      -
    624A  SER      3.0    13.6    +      -       -      +
    625A  PHE*     3.1    23.8    +      -       +      +
    627A  LYS*     1.3    73.9    -      -       -      +
    629A  VAL*     1.3    56.3    -      -       -      +
    631A  GLU*     3.4     9.7    +      -       -      +
    632A  THR*     2.7    39.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 629 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    579A  LEU*     4.0     9.4    -      -       +      -
    588A  LEU*     4.0     4.2    -      -       +      +
    592A  VAL*     3.8    30.1    -      -       +      -
    625A  PHE*     2.9    51.4    +      -       +      +
    626A  GLU*     3.6     9.6    -      -       -      +
    628A  MET*     1.3    76.8    -      -       -      +
    630A  GLU*     1.3    62.2    +      -       -      +
    632A  THR*     3.2     6.1    +      -       -      -
    633A  ARG*     2.9    50.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 630 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    626A  GLU*     2.9    22.2    +      -       +      +
    627A  LYS*     4.0     4.7    -      -       -      +
    629A  VAL*     1.3    79.9    -      -       -      +
    631A  GLU*     1.3    58.6    +      -       +      +
    633A  ARG*     2.8    46.0    +      -       -      +
    634A  GLU*     3.0    41.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 631 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    496A  HIS*     5.7     5.4    +      -       -      -
    499A  ALA*     4.8    20.7    -      -       +      +
    503A  LYS*     5.1     7.3    +      -       -      +
    531A  SER*     4.9     2.6    +      -       -      -
    576A  LYS*     5.7     2.1    +      -       -      -
    627A  LYS*     2.9    57.8    +      -       +      +
    628A  MET*     3.8    10.6    -      -       -      +
    630A  GLU*     1.3    77.3    -      -       +      +
    632A  THR*     1.3    55.6    +      -       -      +
    634A  GLU*     3.5     5.4    +      -       -      +
    635A  SER*     2.9    31.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 632 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    495A  ASN*     5.0    11.0    +      -       -      +
    579A  LEU*     3.9    27.9    -      -       -      +
    582A  ALA*     4.3     2.7    -      -       +      +
    588A  LEU*     3.9    23.8    -      -       +      -
    628A  MET*     2.7    23.4    +      -       -      +
    629A  VAL*     3.5     4.9    -      -       -      -
    631A  GLU*     1.3    74.5    -      -       -      +
    633A  ARG*     1.3    59.8    +      -       -      +
    635A  SER*     3.4     5.6    +      -       -      -
    636A  ILE*     2.9    47.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 633 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    585A  GLU*     2.8    41.9    +      -       -      +
    588A  LEU*     3.6    26.4    -      -       +      +
    589A  LYS*     4.1    17.8    -      -       -      +
    592A  VAL*     5.6     1.4    -      -       -      +
    629A  VAL*     2.9    30.0    +      -       -      +
    630A  GLU*     2.8    46.6    +      -       -      +
    632A  THR*     1.3    77.5    -      -       -      +
    634A  GLU*     1.3    63.2    +      -       -      +
    636A  ILE*     3.4     5.0    +      -       -      +
    637A  LYS*     3.0    53.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 634 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    506A  ARG*     5.5    11.2    -      -       -      +
    630A  GLU*     3.0    27.6    +      -       +      +
    631A  GLU*     4.0     4.9    -      -       -      +
    633A  ARG*     1.3    78.2    -      -       +      +
    635A  SER*     1.3    60.6    +      -       -      +
    637A  LYS*     3.4    32.8    +      -       -      +
    638A  SER*     2.8    30.5    +      -       -      -
    641A  ARG*     5.4     2.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 635 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    495A  ASN*     5.2     2.8    +      -       -      -
    498A  ILE*     3.9     6.8    -      -       -      +
    499A  ALA*     4.5     9.7    +      -       -      -
    502A  GLN*     2.6    28.8    +      -       -      -
    631A  GLU      2.9    19.5    +      -       -      -
    632A  THR*     3.7     5.8    -      -       -      -
    634A  GLU*     1.3    74.7    -      -       -      +
    636A  ILE*     1.3    59.4    +      -       -      +
    638A  SER*     3.2     1.7    +      -       -      -
    639A  GLN*     2.9    55.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 636 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    582A  ALA*     4.1    15.9    -      -       +      +
    583A  THR      4.6     7.9    -      -       -      +
    584A  ASP*     3.8    23.6    -      -       -      +
    585A  GLU*     3.9    19.3    -      -       +      +
    588A  LEU*     4.2    12.3    -      -       +      -
    632A  THR*     2.9    36.6    +      -       +      +
    633A  ARG*     3.5     5.6    -      -       -      +
    635A  SER*     1.3    75.9    -      -       -      +
    637A  LYS*     1.3    59.8    +      -       +      +
    639A  GLN*     3.2     7.2    +      -       -      +
    640A  GLU*     2.9    56.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 637 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    585A  GLU*     5.0     9.4    -      -       +      +
    633A  ARG*     3.0    36.4    +      -       +      +
    634A  GLU*     3.4    32.7    +      -       -      +
    636A  ILE*     1.3    79.1    -      -       +      +
    638A  SER*     1.3    56.4    +      -       -      +
    640A  GLU*     3.5     5.6    +      -       -      +
    641A  ARG*     3.1    45.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 638 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    466A  LYS*     5.9     1.4    +      -       -      -
    502A  GLN*     3.7    26.2    +      -       -      +
    505A  GLU*     5.6     0.7    +      -       -      -
    506A  ARG*     5.9     2.9    +      -       -      -
    634A  GLU      2.8    18.8    +      -       -      -
    635A  SER*     3.5     5.2    -      -       -      -
    637A  LYS*     1.3    77.2    -      -       -      +
    639A  GLN*     1.3    61.1    +      -       -      +
    641A  ARG*     3.5    31.4    +      -       -      +
    642A  GLN*     3.3    18.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 639 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    469A  VAL*     5.3     1.3    -      -       +      -
    473A  GLN*     2.8    43.2    -      -       -      +
    476A  LYS*     5.1    10.1    +      -       -      +
    495A  ASN*     5.5     2.3    -      -       -      +
    498A  ILE*     4.0    17.3    -      -       +      +
    502A  GLN*     3.6    15.3    -      -       -      +
    635A  SER*     2.9    40.7    +      -       -      +
    636A  ILE*     4.1     5.1    +      -       -      +
    638A  SER*     1.3    76.6    -      -       -      +
    640A  GLU*     1.3    57.6    +      -       -      +
    642A  GLN*     3.1    10.8    +      -       +      +
    643A  THR*     2.9    27.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 640 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    583A  THR      3.4    21.7    -      -       -      +
    584A  ASP*     3.8    15.4    -      -       -      +
    585A  GLU*     4.6     3.8    +      -       -      +
    636A  ILE*     2.9    32.8    +      -       -      +
    637A  LYS*     4.0     6.2    +      -       -      +
    639A  GLN*     1.3    73.1    -      -       -      +
    641A  ARG*     1.3    64.8    +      -       -      +
    642A  GLN      3.1     0.7    -      -       -      -
    643A  THR*     3.6    18.6    +      -       -      +
    644A  ILE*     3.4    22.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 641 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    506A  ARG*     6.3     1.0    -      -       -      +
    634A  GLU*     5.4     2.8    +      -       -      -
    637A  LYS*     3.1    36.9    +      -       -      +
    638A  SER*     3.5    34.7    +      -       -      +
    639A  GLN      3.3     0.2    -      -       -      -
    640A  GLU*     1.3    76.5    -      -       -      +
    642A  GLN*     1.3    63.1    +      -       -      +
    644A  ILE*     3.5    20.1    +      -       +      +
    645A  LYS*     3.2    21.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 642 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    363A  GLY      5.3     1.0    +      -       -      -
    466A  LYS*     4.4    30.7    +      -       -      +
    473A  GLN*     6.0     3.4    -      -       -      +
    638A  SER      3.3    10.0    +      -       -      +
    639A  GLN*     3.1    15.8    +      -       +      +
    641A  ARG*     1.3    80.0    -      -       -      +
    643A  THR*     1.3    61.1    +      -       -      +
    645A  LYS*     3.0    29.6    +      -       -      +
    646A  ILE*     3.0    52.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 643 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    639A  GLN      2.9    14.4    +      -       -      -
    640A  GLU*     3.9    18.1    -      -       -      +
    641A  ARG      3.4     0.6    -      -       -      -
    642A  GLN*     1.3    74.8    -      -       -      +
    644A  ILE*     1.3    63.0    +      -       -      +
    646A  ILE*     3.3    30.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 644 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    640A  GLU      3.4    17.9    -      -       -      +
    641A  ARG*     3.5    15.5    +      -       +      +
    642A  GLN      3.2     0.4    -      -       -      -
    643A  THR*     1.3    77.6    -      -       -      +
    645A  LYS*     1.3    63.5    +      -       +      +
    646A  ILE      4.8     1.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 645 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    362A  LYS*     4.0     6.8    -      -       -      +
    641A  ARG*     3.2    18.2    -      -       +      +
    642A  GLN*     3.0    34.9    +      -       -      +
    644A  ILE*     1.3    80.1    -      -       +      +
    646A  ILE*     1.3    60.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 646 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    359A  MET*     5.4     0.2    -      -       -      +
    362A  LYS*     3.7    40.8    +      -       -      +
    363A  GLY      3.5    20.6    -      -       -      +
    364A  ASN*     3.6    49.3    +      -       +      +
    365A  ILE      5.2     1.1    -      -       -      +
    366A  SER*     5.5     2.0    -      -       -      +
    473A  GLN*     5.8     3.6    -      -       -      +
    639A  GLN      5.8     0.2    -      -       -      +
    642A  GLN*     3.0    49.6    +      -       +      +
    643A  THR*     3.3    24.6    +      -       +      +
    644A  ILE      4.8     1.8    -      -       -      -
    645A  LYS*     1.3    83.9    -      -       +      +
----------------------------------------------------------
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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