Contacts of the helix formed by residues 623 - 650 (chain B) in PDB entry 6HBU


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 PRO 623 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    583B  HIS*     4.6     5.8    -      -       -      +
    621B  LEU      4.5     1.1    -      -       -      +
    622B  SER*     1.3    83.8    -      -       -      +
    624B  TRP*     1.3    61.4    +      -       -      +
    625B  GLY      3.2     0.4    -      -       -      -
    626B  LEU*     3.5     7.9    +      -       +      +
    627B  TRP*     3.4    27.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 624 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    620B  ASP*     4.9     6.5    -      -       -      -
    622B  SER*     3.1    11.7    +      -       -      +
    623B  PRO*     1.3    79.0    -      -       -      +
    625B  GLY*     1.3    58.9    +      -       -      +
    626B  LEU      3.1     0.4    -      -       -      -
    627B  TRP*     4.5    14.8    -      -       +      -
    628B  LYS*     2.8    68.8    +      -       +      +
    631B  VAL*     4.2    26.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 625 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    579B  THR*     4.9     0.2    -      -       -      +
    583B  HIS*     4.4    10.7    -      -       -      -
    619B  ILE*     4.6     6.9    -      -       -      +
    620B  ASP*     3.7    28.9    -      -       -      +
    622B  SER*     3.1    18.0    +      -       -      -
    624B  TRP*     1.3    75.9    -      -       -      +
    626B  LEU*     1.3    55.7    +      -       -      +
    628B  LYS*     4.4    10.3    +      -       -      +
    629B  ASN*     3.1    21.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 626 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    508B  VAL*     3.9    24.0    -      -       +      -
    580B  ALA*     3.3    35.2    -      -       +      +
    583B  HIS*     3.4    29.4    -      -       +      +
    584B  ASN*     4.2     8.1    -      -       -      +
    587B  LEU*     6.4     0.7    -      -       +      -
    623B  PRO*     3.5    10.2    +      -       +      +
    624B  TRP      3.1     0.8    -      -       -      -
    625B  GLY*     1.3    77.9    -      -       -      +
    627B  TRP*     1.3    82.9    +      -       +      +
    628B  LYS      3.3     0.4    -      -       -      -
    629B  ASN*     3.2    24.2    +      -       -      +
    630B  HIS*     3.3    20.3    +      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 627 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    508B  VAL*     4.1    28.0    -      -       +      -
    511B  PHE*     3.6    35.9    -      +       +      -
    623B  PRO*     3.4    21.7    -      -       +      +
    624B  TRP*     3.3    18.0    +      -       +      +
    626B  LEU*     1.3    91.7    -      -       +      +
    628B  LYS*     1.3    63.3    +      -       -      +
    629B  ASN      3.2     1.1    -      -       -      -
    630B  HIS*     3.3    32.9    -      +       +      +
    631B  VAL*     3.3    31.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 628 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    575B  ARG*     5.5    11.2    -      -       -      +
    576B  TYR*     4.8     3.9    -      -       +      -
    620B  ASP*     3.3    26.8    +      -       -      +
    624B  TRP*     2.8    43.1    +      -       +      +
    625B  GLY*     4.7     9.9    -      -       -      +
    626B  LEU      3.3     0.2    -      -       -      -
    627B  TRP*     1.3    77.7    -      -       -      +
    629B  ASN*     1.3    69.8    +      -       -      +
    631B  VAL*     3.5     9.8    -      -       +      +
    632B  ALA*     3.3    24.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 629 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    575B  ARG*     4.4     5.4    +      -       -      -
    576B  TYR*     3.3    47.2    -      -       -      +
    579B  THR*     3.5    27.8    -      -       -      +
    580B  ALA*     3.6    16.5    -      -       +      +
    625B  GLY      3.1    25.6    +      -       -      -
    626B  LEU      3.2     9.5    +      -       -      +
    627B  TRP      3.2     0.4    -      -       -      -
    628B  LYS*     1.3    87.8    -      -       -      +
    630B  HIS*     1.3    58.4    +      -       -      +
    632B  ALA      4.0     0.6    -      -       -      -
    633B  LEU*     3.3    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 630 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    508B  VAL*     4.4     2.2    +      -       +      -
    511B  PHE*     3.5    29.2    -      +       +      -
    512B  THR*     2.7    40.5    +      -       +      +
    515B  MET*     3.6    16.6    -      -       +      +
    580B  ALA*     3.7    20.2    -      -       +      -
    626B  LEU*     3.3    22.5    +      -       +      -
    627B  TRP*     3.3    40.3    +      +       +      +
    628B  LYS      3.4     0.2    -      -       -      -
    629B  ASN*     1.3    77.6    -      -       -      +
    631B  VAL*     1.3    61.2    +      -       +      +
    632B  ALA      3.3     1.3    -      -       -      -
    633B  LEU*     3.8     6.5    -      -       +      +
    634B  ALA*     3.0    25.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 631 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    624B  TRP*     4.2    23.6    -      -       +      -
    627B  TRP*     3.3    18.5    +      -       +      +
    628B  LYS*     3.5    17.5    -      -       +      +
    630B  HIS*     1.3    76.7    -      -       +      +
    632B  ALA*     1.3    61.7    +      -       +      +
    633B  LEU      3.4     0.2    -      -       -      -
    634B  ALA*     3.8     7.5    -      -       +      +
    635B  CYS*     3.2    34.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 632 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    576B  TYR*     3.6    35.2    -      -       +      +
    628B  LYS*     3.3    19.4    +      -       +      +
    629B  ASN      4.2     0.4    -      -       -      +
    630B  HIS      3.3     0.2    -      -       -      -
    631B  VAL*     1.3    78.4    -      -       +      +
    633B  LEU*     1.3    60.4    +      -       -      +
    635B  CYS*     3.8     7.1    +      -       -      +
    636B  MET*     3.2    30.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 633 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    512B  THR*     4.9     2.9    -      -       +      +
    515B  MET*     3.8    24.5    -      -       +      +
    516B  VAL*     3.7    22.4    -      -       +      -
    519B  SER*     3.0    34.7    +      -       -      +
    573B  ILE*     3.8    32.5    -      -       +      +
    576B  TYR*     3.9    25.1    -      -       +      +
    577B  GLY*     4.5     3.8    -      -       -      +
    580B  ALA*     6.3     0.2    -      -       +      -
    629B  ASN      3.3    20.7    +      -       -      +
    630B  HIS*     3.7     9.4    +      -       +      +
    632B  ALA*     1.3    78.4    -      -       -      +
    634B  ALA*     1.3    62.5    +      -       -      +
    635B  CYS      3.3     0.7    -      -       -      -
    636B  MET*     3.3     4.1    +      -       -      +
    637B  ILE*     3.1    14.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 634 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    515B  MET*     3.6    16.1    -      -       +      +
    630B  HIS      3.0    18.6    +      -       -      +
    631B  VAL*     3.7     8.0    +      -       -      +
    632B  ALA      3.4     0.2    -      -       -      -
    633B  LEU*     1.3    76.0    -      -       -      +
    635B  CYS*     1.3    63.2    +      -       -      +
    637B  ILE*     3.4     7.4    +      -       +      +
    638B  VAL*     3.2    29.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 635 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    631B  VAL*     3.2    25.9    +      -       -      +
    632B  ALA*     4.1     7.4    -      -       -      +
    633B  LEU      3.3     0.2    -      -       -      -
    634B  ALA*     1.3    77.0    -      -       -      +
    636B  MET*     1.3    59.1    +      -       +      +
    637B  ILE      3.3     0.2    -      -       -      -
    638B  VAL*     4.0     5.3    -      -       -      +
    639B  ILE*     3.2    41.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 636 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    519B  SER*     4.5     8.7    -      -       -      +
    522B  SER*     4.3     1.9    -      -       -      -
    548B  MET*     4.9     1.6    -      -       +      -
    570B  TYR      4.7     3.6    -      -       -      +
    571B  PHE*     3.3    32.8    -      -       +      +
    573B  ILE*     3.7    23.1    -      -       +      -
    576B  TYR*     4.2    22.7    -      -       -      -
    632B  ALA      3.2    17.2    +      -       -      +
    633B  LEU*     3.3    14.3    +      -       -      +
    635B  CYS*     1.3    77.2    -      -       +      +
    637B  ILE*     1.3    59.2    +      -       -      +
    639B  ILE*     4.7     5.4    -      -       +      +
    640B  PHE*     3.1    58.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 637 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    515B  MET*     3.8    24.2    -      -       +      -
    518B  TYR*     3.7    26.5    -      -       +      +
    519B  SER*     3.3    26.0    -      -       -      +
    522B  SER*     3.8    14.8    -      -       -      +
    633B  LEU      3.1    15.8    +      -       -      +
    634B  ALA*     3.7     7.9    -      -       -      +
    635B  CYS      3.3     0.4    -      -       -      -
    636B  MET*     1.3    78.3    -      -       -      +
    638B  VAL*     1.3    62.6    +      -       +      +
    641B  LEU*     2.9    49.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 638 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    634B  ALA*     3.2    17.1    +      -       +      +
    635B  CYS*     3.8     5.8    +      -       -      +
    637B  ILE*     1.3    79.8    -      -       +      +
    639B  ILE*     1.3    60.1    +      -       +      +
    641B  LEU*     3.9     2.4    -      -       -      +
    642B  THR*     2.4    40.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 639 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    635B  CYS*     3.2    28.8    +      -       +      +
    636B  MET*     4.7     4.3    -      -       +      -
    638B  VAL*     1.3    81.2    -      -       +      +
    640B  PHE*     1.3    67.4    +      -       +      +
    642B  THR*     3.2     5.7    +      -       -      -
    643B  ILE*     3.0    45.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 640 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    519B  SER      3.9     6.3    -      -       -      -
    522B  SER*     3.3    20.8    -      -       -      +
    523B  MET*     3.6    48.5    -      -       +      -
    526B  ALA*     3.3    16.9    -      -       +      +
    548B  MET*     5.7     0.4    -      -       +      -
    571B  PHE*     6.4     1.1    -      +       -      -
    573B  ILE*     4.6     0.9    -      -       +      -
    636B  MET*     3.1    51.8    +      -       +      +
    637B  ILE      3.6     1.6    +      -       -      -
    639B  ILE*     1.3    87.3    -      -       +      +
    641B  LEU*     1.3    56.8    +      -       -      +
    643B  ILE*     4.0    16.2    -      -       +      -
    644B  ALA*     3.2    24.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 641 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    470B  PHE*     3.4    32.1    -      -       +      -
    474B  LEU*     3.8    32.1    -      -       +      -
    478B  LEU*     6.5     0.9    -      -       +      -
    522B  SER*     3.4    21.1    -      -       -      +
    525B  LEU*     3.8    16.2    -      -       +      -
    637B  ILE*     2.9    38.7    +      -       +      +
    638B  VAL*     3.9     2.7    -      -       -      +
    640B  PHE*     1.3    76.5    -      -       -      +
    642B  THR*     1.3    60.8    +      -       -      +
    644B  ALA*     3.9     3.4    -      -       -      -
    645B  TYR*     3.3    19.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 642 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    638B  VAL*     2.4    31.1    +      -       -      +
    639B  ILE*     3.2     6.4    +      -       -      -
    641B  LEU*     1.3    77.5    -      -       -      +
    643B  ILE*     1.3    61.0    +      -       +      +
    644B  ALA      3.3     0.2    -      -       -      -
    645B  TYR*     3.3     7.1    +      -       +      +
    646B  LEU*     3.0    47.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 643 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    526B  ALA*     4.0    22.4    -      -       +      +
    639B  ILE*     3.0    32.5    +      -       +      +
    640B  PHE*     4.1    20.2    -      -       +      +
    642B  THR*     1.3    77.5    -      -       -      +
    644B  ALA*     1.3    56.5    +      -       -      +
    646B  LEU*     3.4     7.2    +      -       +      +
    647B  LYS*     3.0    38.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 644 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    470B  PHE*     4.0    14.1    -      -       +      -
    525B  LEU*     3.5    41.7    -      -       +      +
    526B  ALA*     4.1     2.0    -      -       -      +
    529B  ALA*     3.4    21.7    -      -       +      +
    640B  PHE      3.2    20.4    +      -       -      +
    641B  LEU*     4.1     3.8    -      -       -      -
    642B  THR      3.3     0.4    -      -       -      -
    643B  ILE*     1.3    77.2    -      -       -      +
    645B  TYR*     1.3    61.1    +      -       -      +
    647B  LYS*     4.7     0.2    -      -       -      -
    648B  LEU*     3.5    14.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 645 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    466B  VAL*     3.6    13.9    -      -       +      +
    467B  SER*     3.6    42.1    +      -       -      -
    470B  PHE*     4.0    31.8    -      +       +      -
    641B  LEU      3.3    19.7    +      -       -      +
    642B  THR*     3.7     7.9    -      -       +      +
    643B  ILE      3.3     0.6    -      -       -      -
    644B  ALA*     1.3    78.8    -      -       -      +
    646B  LEU*     1.3    72.7    +      -       +      +
    648B  LEU*     3.1     6.7    +      -       -      +
    649B  LEU*     2.9    57.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 646 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    642B  THR*     3.0    36.7    +      -       +      +
    643B  ILE*     4.1     6.1    -      -       +      +
    645B  TYR*     1.3    90.1    -      -       +      +
    647B  LYS*     1.3    59.1    +      -       +      +
    649B  LEU*     3.7    12.3    -      -       +      -
    650B  PHE*     2.9    60.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 647 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    526B  ALA      2.9    24.1    +      -       -      +
    527B  ILE*     2.9    30.1    +      -       -      +
    529B  ALA*     3.3    30.1    +      -       +      +
    530B  GLY*     4.2     7.6    -      -       -      -
    531B  GLN*     5.1     0.6    +      -       -      -
    643B  ILE*     3.0    29.8    +      -       +      +
    645B  TYR      3.2     0.2    -      -       -      -
    646B  LEU*     1.3    77.0    -      -       +      +
    648B  LEU*     1.3    60.6    +      -       -      +
    650B  PHE*     5.4     1.1    -      -       -      -
    651B  LEU*     3.4    22.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 648 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    448B  PHE*     3.8    31.0    -      -       +      +
    455B  PHE*     3.9    25.7    -      -       +      -
    466B  VAL*     4.0    12.8    -      -       +      -
    469B  TYR*     4.8     9.2    -      -       +      -
    470B  PHE*     3.8    35.4    -      -       +      -
    529B  ALA*     4.0     5.6    -      -       +      -
    530B  GLY*     3.8    24.9    -      -       -      +
    644B  ALA      3.5    10.7    +      -       -      +
    645B  TYR      3.1     6.1    +      -       -      +
    647B  LYS*     1.3    78.7    -      -       -      +
    649B  LEU*     1.3    53.1    +      -       -      +
    651B  LEU*     3.6     6.0    -      -       -      +
    653B  LYS*     2.6    33.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 649 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    459B  TYR*     4.7     7.6    -      -       -      +
    466B  VAL*     3.8    28.4    -      -       +      +
    645B  TYR*     2.9    42.7    +      -       +      +
    646B  LEU*     3.5    18.6    +      -       +      +
    647B  LYS      3.5     0.2    -      -       -      -
    648B  LEU*     1.3    78.3    -      -       -      +
    650B  PHE*     1.3    75.9    +      -       +      +
    651B  LEU      3.2     2.7    +      -       -      +
    653B  LYS*     3.0    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 650 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    646B  LEU*     2.9    61.5    +      -       +      +
    647B  LYS*     4.4     1.8    -      -       -      -
    649B  LEU*     1.3    86.2    -      -       +      +
    651B  LEU*     1.3    64.2    +      -       -      +
    652B  LYS*     3.7     6.4    +      -       -      +
----------------------------------------------------------
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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