Contacts of the helix formed by residues 740 - 765 (chain B) in PDB entry 2BKU


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 740 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    738B  ASN*     2.7    36.0    +      -       +      +
    739B  GLY*     1.3    83.7    -      -       -      +
    741B  LEU*     1.3    82.9    +      -       +      +
    742B  GLU*     4.1     2.3    +      -       -      +
    743B  ALA*     3.3    24.0    +      -       -      +
    744B  LEU*     3.6     8.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 741 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    740B  THR*     1.3    87.1    -      -       +      +
    742B  GLU*     1.3    90.2    +      -       +      +
    744B  LEU*     3.8     1.9    +      -       -      +
    745B  ASP*     3.4    27.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 742 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    696B  ARG*     6.1     0.7    -      -       -      -
    740B  THR*     5.0     0.9    -      -       -      +
    741B  LEU*     1.3    96.9    -      -       +      +
    743B  ALA*     1.3    69.1    +      -       -      +
    744B  LEU      2.9     0.3    +      -       -      -
    745B  ASP*     3.0     6.9    +      -       -      -
    746B  TYR*     2.8    32.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 743 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    736B  PRO*     3.9     9.8    -      -       +      +
    737B  GLU*     4.3    10.2    +      -       -      +
    738B  ASN*     3.1    42.4    -      -       -      +
    740B  THR*     3.3    27.3    +      -       -      +
    742B  GLU*     1.3    79.7    -      -       -      +
    744B  LEU*     1.3    59.3    +      -       +      +
    746B  TYR*     4.0     6.4    -      -       -      +
    747B  GLN*     3.3    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 744 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    736B  PRO*     3.7    28.5    -      -       +      -
    739B  GLY*     4.0    21.3    -      -       -      +
    740B  THR      3.6    14.9    +      -       -      +
    741B  LEU      4.5     2.2    -      -       -      +
    742B  GLU      3.1     0.6    -      -       -      -
    743B  ALA*     1.3    76.3    -      -       +      +
    745B  ASP*     1.3    62.1    +      -       -      +
    746B  TYR      3.2     2.2    -      -       -      -
    747B  GLN*     3.5     6.9    -      -       -      +
    748B  ILE*     2.7    40.8    +      -       +      +
    791B  GLN*     3.6    29.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 745 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    741B  LEU*     3.4    22.1    +      -       -      +
    742B  GLU*     3.0     7.2    +      -       -      +
    744B  LEU*     1.3    81.5    -      -       -      +
    746B  TYR*     1.3    57.5    +      -       -      +
    748B  ILE*     4.0     8.4    -      -       -      +
    749B  LYS*     3.2    33.2    +      -       -      +
    791B  GLN*     5.5     2.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 746 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    696B  ARG*     2.7    55.1    +      -       +      +
    697B  GLU*     4.9     0.7    -      -       -      -
    699B  LYS*     4.0    19.6    -      -       +      +
    700B  PRO*     4.4     9.2    -      -       +      -
    737B  GLU*     4.3    24.5    -      -       +      +
    742B  GLU*     2.8    20.4    +      -       +      +
    743B  ALA*     4.0     5.2    -      -       -      +
    745B  ASP*     1.3    74.8    -      -       -      +
    747B  GLN*     1.3    58.8    +      -       -      +
    748B  ILE      3.2     0.2    -      -       -      -
    749B  LYS*     2.9    32.2    +      -       +      +
    750B  VAL*     2.8    51.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 747 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    731B  ALA      5.3     0.4    +      -       -      +
    732B  GLN      4.9     2.6    +      -       -      -
    734B  THR*     2.9    32.8    +      -       +      +
    735B  LYS*     4.1     6.7    -      -       -      +
    736B  PRO*     4.0    26.1    -      -       +      +
    743B  ALA      3.3    17.0    +      -       -      +
    744B  LEU*     3.2     6.7    +      -       -      +
    746B  TYR*     1.3    84.9    -      -       +      +
    748B  ILE*     1.3    75.7    +      -       -      +
    750B  VAL*     3.4     8.7    +      -       +      +
    751B  LEU*     3.0    58.5    +      -       +      +
    785B  GLN*     5.6     0.6    +      -       -      -
    789B  ASP*     5.1     3.5    -      -       -      +
    791B  GLN*     5.1     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 748 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    744B  LEU      2.7    23.2    +      -       -      +
    745B  ASP*     4.0    10.1    -      -       -      +
    747B  GLN*     1.3    87.1    -      -       -      +
    749B  LYS*     1.3    55.6    +      -       +      +
    751B  LEU*     3.0    11.9    +      -       +      +
    752B  GLU*     2.8    58.0    +      -       +      +
    789B  ASP*     4.9     3.8    -      -       -      +
    791B  GLN*     3.1    56.1    -      -       +      +
    792B  LEU*     4.5     9.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 749 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    697B  GLU*     5.7     8.5    -      -       -      +
    700B  PRO*     3.9    20.1    -      -       +      +
    745B  ASP*     3.2    24.3    +      -       -      +
    746B  TYR*     2.9    36.2    +      -       +      +
    748B  ILE*     1.3    76.8    -      -       +      +
    750B  VAL*     1.3    62.4    +      -       -      +
    752B  GLU*     3.5    14.5    +      -       -      +
    753B  ALA*     3.2    22.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 750 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    699B  LYS*     4.5    13.9    -      -       +      +
    700B  PRO*     4.4    16.6    -      -       +      -
    703B  LEU*     4.0     7.9    -      -       +      +
    731B  ALA*     3.9    38.8    -      -       +      +
    734B  THR*     6.0     1.8    -      -       +      -
    746B  TYR*     2.8    47.5    +      -       +      +
    747B  GLN*     3.5    11.7    -      -       +      +
    749B  LYS*     1.3    72.5    -      -       -      +
    751B  LEU*     1.3    61.7    +      -       +      +
    753B  ALA*     3.0     5.8    +      -       -      +
    754B  VAL*     2.9    25.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 751 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    731B  ALA      4.5     4.3    -      -       -      +
    732B  GLN*     3.8    31.6    -      -       -      +
    747B  GLN*     3.0    50.5    +      -       -      +
    748B  ILE*     3.0    11.4    +      -       +      +
    750B  VAL*     1.3    76.1    -      -       +      +
    752B  GLU*     1.3    61.6    +      -       -      +
    754B  VAL*     3.4     4.3    +      -       +      +
    755B  LEU*     3.1    17.7    +      -       -      +
    782B  PHE*     3.2    24.4    -      -       +      -
    785B  GLN*     3.8    15.0    -      -       -      +
    789B  ASP*     5.3     3.8    -      -       -      +
    792B  LEU*     3.9    34.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 752 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    748B  ILE*     2.8    41.0    +      -       +      +
    749B  LYS*     3.9    15.0    -      -       -      +
    750B  VAL      3.2     0.2    -      -       -      -
    751B  LEU*     1.3    73.1    -      -       -      +
    753B  ALA*     1.3    56.9    +      -       -      +
    755B  LEU*     3.4    11.9    -      -       +      +
    756B  ASP*     3.0    31.2    +      -       -      +
    791B  GLN      5.4     1.4    -      -       -      +
    792B  LEU*     4.8     8.1    -      -       +      -
    795B  GLU*     4.6    14.2    -      -       -      +
    798B  THR*     3.6    24.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 753 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    700B  PRO*     3.3    33.0    -      -       +      +
    703B  LEU*     3.5    23.5    -      -       +      +
    704B  SER*     3.3    13.7    -      -       -      +
    749B  LYS      3.2    13.0    +      -       -      +
    750B  VAL      3.0     9.9    +      -       -      +
    752B  GLU*     1.3    76.5    -      -       -      +
    754B  VAL*     1.3    62.5    +      -       -      +
    756B  ASP*     3.3     3.9    +      -       -      +
    757B  ALA*     3.1    16.5    +      -       -      +
    838D  GLN*     4.8     2.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 754 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    703B  LEU*     4.0     4.9    -      -       +      +
    728B  CYS*     3.6    23.6    -      -       +      -
    731B  ALA*     3.9    20.2    -      -       +      -
    732B  GLN*     3.8    12.8    -      -       +      +
    750B  VAL*     2.9    19.2    +      -       +      +
    751B  LEU*     3.4     9.8    +      -       -      +
    753B  ALA*     1.3    72.7    -      -       -      +
    755B  LEU*     1.3    61.3    +      -       -      +
    757B  ALA*     2.9    22.3    +      -       -      +
    758B  TYR*     3.0    45.3    +      -       +      -
    782B  PHE*     3.7    17.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 755 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    751B  LEU      3.1    10.1    +      -       -      +
    752B  GLU*     3.4    15.3    -      -       +      +
    754B  VAL*     1.3    80.9    -      -       -      +
    756B  ASP*     1.3    62.6    +      -       -      +
    758B  TYR*     3.4     3.8    +      -       -      +
    759B  VAL*     3.1    43.0    +      -       +      +
    782B  PHE*     3.7    22.8    -      -       +      -
    786B  VAL*     5.4     0.9    -      -       +      -
    798B  THR*     3.6    44.2    -      -       +      +
    801B  ALA*     3.7    16.6    -      -       +      -
    802B  ALA*     4.5     5.2    -      -       +      +
    805B  LEU*     4.1    16.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 756 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    704B  SER*     2.6    39.0    +      -       -      +
    707B  GLY*     3.5     6.5    -      -       -      -
    752B  GLU*     3.0    21.3    +      -       -      +
    753B  ALA*     3.5     4.4    -      -       -      +
    754B  VAL      3.2     0.4    -      -       -      -
    755B  LEU*     1.3    75.4    -      -       -      +
    757B  ALA*     1.3    62.5    +      -       -      +
    759B  VAL*     4.6     1.1    -      -       -      -
    760B  GLY      3.1    17.7    +      -       -      -
    838D  GLN*     4.4     6.5    +      -       -      +
    841D  SER*     3.2    18.6    -      -       -      -
    842D  GLN*     2.9    42.9    +      -       +      +
    843D  ALA      4.8     0.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 757 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    703B  LEU*     3.4    21.1    +      -       -      +
    706B  PHE*     4.5     7.9    -      -       +      -
    707B  GLY*     3.8    15.1    -      -       -      +
    724B  ILE*     5.2     0.2    -      -       +      -
    728B  CYS*     4.1    21.8    -      -       -      -
    753B  ALA      3.1     7.0    +      -       -      +
    754B  VAL*     2.9    11.0    +      -       -      +
    756B  ASP*     1.3    77.1    -      -       -      +
    758B  TYR*     1.3    56.9    +      -       -      +
    760B  GLY*     3.3     1.7    +      -       -      -
    761B  ILE*     2.9    39.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 758 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    725B  MET*     3.5    33.7    -      -       +      -
    728B  CYS*     2.5    36.6    +      -       -      -
    732B  GLN*     2.7    16.5    +      -       -      -
    754B  VAL*     3.0    36.3    +      -       +      +
    755B  LEU*     4.1     2.9    -      -       -      +
    757B  ALA*     1.3    71.9    -      -       -      +
    759B  VAL*     1.3    61.7    +      -       -      +
    761B  ILE*     3.3     9.2    +      -       +      +
    762B  VAL*     2.9    34.7    +      -       -      +
    778B  THR*     3.7    12.3    -      -       +      +
    779B  ILE*     3.9    31.2    -      -       +      -
    782B  PHE*     3.7    26.2    -      +       +      -
    805B  LEU*     4.1    16.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 759 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    755B  LEU*     3.1    42.4    +      -       +      +
    756B  ASP*     3.9     2.9    -      -       -      +
    758B  TYR*     1.3    76.1    -      -       -      +
    760B  GLY*     1.3    58.3    +      -       -      +
    762B  VAL*     3.4     1.9    +      -       -      +
    763B  ALA*     3.0    28.3    +      -       -      +
    801B  ALA*     4.3    13.0    -      -       +      +
    805B  LEU*     3.7    20.2    -      -       +      -
    842D  GLN*     3.9     8.5    -      -       +      -
    843D  ALA*     3.7    30.5    -      -       +      +
    846D  ASP*     3.9    10.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 760 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    707B  GLY      3.4    24.5    -      -       -      -
    710B  ALA*     3.9     0.2    -      -       -      -
    711B  SER*     3.2    18.3    +      -       -      -
    756B  ASP      3.1    11.1    +      -       -      -
    757B  ALA      3.7     2.5    -      -       -      -
    759B  VAL*     1.3    76.5    -      -       -      +
    761B  ILE*     1.3    51.8    +      -       -      +
    763B  ALA*     3.4     2.0    +      -       -      +
    764B  GLY      2.8    28.9    +      -       -      -
    842D  GLN*     3.6    13.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 761 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    706B  PHE*     5.1     1.6    -      -       +      +
    710B  ALA*     3.8    20.0    -      -       +      -
    717B  PHE*     4.2     9.0    -      -       +      -
    721B  LEU*     3.9    17.7    -      -       +      -
    724B  ILE*     4.1    25.8    -      -       +      -
    725B  MET*     4.4    12.6    -      -       -      -
    757B  ALA*     2.9    29.4    +      -       +      +
    758B  TYR*     3.3    11.6    +      -       +      +
    760B  GLY*     1.3    73.4    -      -       -      +
    762B  VAL*     1.3    59.4    +      -       -      +
    764B  GLY*     3.3     0.3    +      -       -      -
    765B  LEU*     2.8    51.0    +      -       +      +
    772B  LEU*     3.9    18.8    -      -       +      -
    779B  ILE*     5.7     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 762 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    758B  TYR      2.9    22.8    +      -       -      +
    759B  VAL      3.9     3.4    -      -       -      +
    761B  ILE*     1.3    70.9    -      -       +      +
    763B  ALA*     1.3    66.1    +      -       -      +
    765B  LEU*     3.6     1.9    +      -       -      -
    766B  HIS*     3.3    21.5    +      -       -      +
    772B  LEU*     4.1    19.3    -      -       +      -
    779B  ILE*     4.5     8.1    -      -       +      -
    805B  LEU*     4.0    15.0    -      -       +      -
    808B  ASP*     3.9    30.3    -      -       +      +
    809B  ILE*     3.9    27.4    -      -       +      -
    812B  MET*     4.1    16.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 763 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    711B  SER*     4.2     8.9    -      -       -      +
    759B  VAL      3.0    13.7    +      -       -      +
    760B  GLY      3.5     5.8    -      -       -      +
    762B  VAL*     1.3    80.9    -      -       -      +
    764B  GLY*     1.3    63.1    +      -       -      +
    765B  LEU      3.3     0.9    +      -       -      -
    766B  HIS*     3.4    15.8    +      -       -      +
    846D  ASP*     3.3    30.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 764 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    710B  ALA*     3.3    26.2    -      -       -      -
    711B  SER*     3.7     9.4    -      -       -      +
    714B  GLY*     3.3    20.4    -      -       -      -
    715B  ALA      4.5     0.2    +      -       -      -
    760B  GLY      2.8    16.0    +      -       -      -
    761B  ILE      3.3     2.0    +      -       -      -
    763B  ALA*     1.3    74.9    -      -       -      +
    765B  LEU*     1.3    59.7    +      -       -      +
    766B  HIS*     3.4     2.3    +      -       -      +
    767B  ASP*     4.9     2.4    +      -       -      +
    768B  LYS*     5.6     1.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 765 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    710B  ALA*     6.3     1.3    -      -       +      -
    714B  GLY      3.9    25.6    -      -       -      +
    715B  ALA*     4.3     0.7    -      -       -      -
    717B  PHE*     5.6     5.6    -      -       +      -
    718B  ILE*     3.9    22.2    -      -       +      +
    721B  LEU*     4.2    24.0    -      -       +      -
    761B  ILE*     2.8    37.0    +      -       +      +
    762B  VAL*     3.8     4.5    -      -       -      +
    763B  ALA      3.3     0.2    -      -       -      -
    764B  GLY*     1.3    76.9    -      -       -      +
    766B  HIS*     1.3    64.7    +      -       -      +
    767B  ASP      3.2     2.9    -      -       -      +
    768B  LYS*     2.9    36.0    +      -       +      +
    771B  ALA*     4.4     7.9    -      -       +      -
    772B  LEU*     4.4    11.0    -      -       +      -
    812B  MET*     3.1    18.6    -      -       +      +
----------------------------------------------------------
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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