Contacts of the helix formed by residues 754 - 777 (chain A) in PDB entry 2P8Q


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 MET 754 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    707A  ARG*     4.0    23.6    -      -       -      +
    747A  VAL*     3.6    45.2    -      -       +      +
    748A  ASP      5.8     0.7    -      -       -      +
    751A  ASP*     3.3    29.4    -      -       +      +
    752A  TYR      2.9     0.4    -      -       -      -
    753A  ASP*     1.3    87.9    -      -       -      +
    755A  VAL*     1.3    59.6    +      -       -      +
    756A  ASP      3.0     2.5    -      -       -      -
    757A  TYR*     3.6     8.5    -      -       +      +
    758A  LEU*     2.8    33.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 755 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    747A  VAL      6.0     1.3    -      -       -      -
    749A  LYS*     4.8    12.8    -      -       +      +
    751A  ASP      3.8    14.3    +      -       -      +
    752A  TYR*     3.1    41.1    +      -       +      +
    754A  MET*     1.3    79.0    -      -       -      +
    756A  ASP*     1.3    76.7    +      -       -      +
    757A  TYR      3.6     0.2    -      -       -      -
    758A  LEU*     3.8     6.3    -      -       -      +
    759A  ASN*     3.2    30.4    +      -       -      +
    809A  ASP*     3.7    33.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 756 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    752A  TYR      3.6     7.4    +      -       -      +
    753A  ASP      4.9     1.6    -      -       -      -
    754A  MET      3.0     0.2    -      -       -      -
    755A  VAL*     1.3    96.0    -      -       +      +
    757A  TYR*     1.3    59.1    +      -       -      +
    758A  LEU      4.1     0.4    -      -       -      +
    759A  ASN*     3.9    22.7    -      -       -      +
    760A  GLU*     3.7    19.2    +      -       -      +
    811A  THR*     4.4     8.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 757 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    707A  ARG*     2.5    84.1    +      -       +      +
    708A  SER*     4.4     1.8    -      -       -      -
    710A  LYS*     4.4     7.8    -      -       -      +
    711A  PRO*     4.1    17.0    -      -       +      +
    747A  VAL*     5.6     6.3    -      -       +      -
    753A  ASP      3.9    12.7    +      -       -      +
    754A  MET*     3.2    12.9    +      -       +      +
    756A  ASP*     1.3    77.4    -      -       -      +
    758A  LEU*     1.3    64.1    +      -       +      +
    759A  ASN      3.2     1.8    -      -       -      -
    760A  GLU*     3.5    17.0    -      -       +      +
    761A  LEU*     2.9    54.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 758 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    745A  ALA*     3.4    32.8    -      -       +      +
    746A  GLN*     4.1     1.6    -      -       -      -
    747A  VAL*     3.6    44.4    -      -       +      +
    754A  MET      2.8    17.7    +      -       -      +
    755A  VAL*     3.8     9.2    -      -       +      +
    757A  TYR*     1.3    82.8    -      -       +      +
    759A  ASN*     1.3    58.8    +      -       -      +
    761A  LEU*     3.8     7.1    -      -       +      +
    762A  ARG*     2.9    69.2    +      -       +      +
    807A  ASP*     5.1     1.3    -      -       -      +
    809A  ASP*     4.9     7.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 759 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    755A  VAL*     3.2    20.7    +      -       -      +
    756A  ASP*     3.9    15.3    -      -       -      +
    757A  TYR      3.2     0.2    -      -       -      -
    758A  LEU*     1.3    78.1    -      -       -      +
    760A  GLU*     1.3    67.9    +      -       -      +
    762A  ARG*     4.2    12.9    -      -       -      +
    763A  GLU*     2.9    28.0    +      -       -      +
    809A  ASP*     3.6    28.7    +      -       -      +
    810A  HIS*     4.0     0.7    -      -       -      -
    811A  THR*     3.2    45.8    +      -       +      +
    814A  VAL*     3.5     9.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 760 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    707A  ARG*     5.8     0.5    +      -       -      -
    708A  SER*     4.1    19.4    +      -       -      +
    711A  PRO*     4.0    20.1    -      -       +      +
    712A  GLN*     4.8     9.9    -      -       -      +
    756A  ASP*     3.7    20.4    +      -       -      +
    757A  TYR*     3.3    19.5    +      -       +      +
    759A  ASN*     1.3    81.4    -      -       -      +
    761A  LEU*     1.3    55.8    +      -       -      +
    763A  GLU*     3.8     9.0    -      -       -      +
    764A  SER*     2.9    27.1    +      -       -      +
     52B  LYS*     5.7     7.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 761 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    710A  LYS*     4.3    11.4    -      -       +      -
    711A  PRO*     3.8    26.9    -      -       +      -
    714A  LEU*     3.8    24.2    -      -       +      -
    742A  ALA*     3.7    27.4    -      -       +      +
    745A  ALA*     4.3    14.8    -      -       +      -
    757A  TYR*     2.9    40.9    +      -       +      +
    758A  LEU*     4.0     9.9    -      -       +      +
    760A  GLU*     1.3    76.5    -      -       -      +
    762A  ARG*     1.3    64.6    +      -       +      +
    763A  GLU      3.4     0.2    -      -       -      -
    764A  SER*     3.4     2.4    -      -       -      -
    765A  CYS*     3.1    21.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 762 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    742A  ALA      5.7     2.5    -      -       -      +
    743A  SER      5.7     0.4    +      -       -      +
    745A  ALA      4.3    10.0    +      -       -      +
    746A  GLN*     4.9     3.6    -      -       -      +
    758A  LEU*     2.9    59.3    +      -       +      +
    759A  ASN*     3.2    14.5    +      -       -      +
    761A  LEU*     1.3    75.4    -      -       +      +
    763A  GLU*     1.3    68.4    +      -       -      +
    765A  CYS*     3.0    15.0    +      -       -      +
    766A  LEU*     3.0    19.2    +      -       +      +
    800A  PHE*     3.9    22.5    -      -       +      -
    803A  HIS*     4.4    12.9    -      -       -      -
    804A  ILE*     2.9    47.5    -      -       +      +
    807A  ASP*     2.9    34.7    +      -       -      +
    809A  ASP*     4.2     9.5    +      -       -      -
    814A  VAL*     4.6     8.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 763 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    759A  ASN      2.9    17.2    +      -       -      +
    760A  GLU*     3.8     7.0    -      -       -      +
    762A  ARG*     1.3    75.8    -      -       -      +
    764A  SER*     1.3    64.9    +      -       -      +
    766A  LEU*     3.0    12.3    +      -       -      +
    767A  GLU*     2.9    32.3    +      -       -      +
    811A  THR*     4.5     4.7    +      -       -      +
    813A  GLY*     3.7    28.9    -      -       -      +
    814A  VAL*     3.8    13.7    +      -       +      +
    817A  CYS*     3.5    24.0    -      -       -      -
     52B  LYS*     3.1    31.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 764 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    711A  PRO*     2.9    45.6    +      -       -      +
    712A  GLN*     5.0     3.1    +      -       -      -
    714A  LEU*     4.3     5.6    -      -       -      -
    715A  SER*     3.7    18.5    +      -       -      -
    760A  GLU*     2.9    17.2    +      -       -      +
    761A  LEU      3.4    10.5    -      -       -      -
    763A  GLU*     1.3    80.9    -      -       -      +
    765A  CYS*     1.3    62.1    +      -       -      +
    767A  GLU*     3.3     5.8    +      -       -      +
    768A  ALA*     3.0    21.1    +      -       -      +
     52B  LYS*     5.7     2.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with CYS 765 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    714A  LEU*     3.9     9.2    -      -       -      -
    739A  LEU*     4.2    10.5    -      -       +      -
    742A  ALA*     3.9    39.7    -      -       -      -
    743A  SER*     4.3    10.3    -      -       -      +
    761A  LEU*     3.1    24.0    +      -       -      -
    762A  ARG*     3.0    11.1    +      -       -      +
    764A  SER*     1.3    76.9    -      -       -      +
    766A  LEU*     1.3    62.2    +      -       -      +
    768A  ALA*     3.0    18.6    +      -       -      +
    769A  TYR*     3.0    22.3    +      -       +      -
    800A  PHE*     3.9    15.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 766 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    762A  ARG*     3.0    14.8    +      -       +      +
    763A  GLU*     3.0    10.7    +      -       -      +
    765A  CYS*     1.3    76.1    -      -       -      +
    767A  GLU*     1.3    61.4    +      -       -      +
    769A  TYR*     3.4     5.8    +      -       +      +
    770A  THR*     3.0    27.7    +      -       -      -
    800A  PHE*     3.6    21.1    -      -       +      -
    801A  ILE*     3.4    28.7    -      -       +      -
    804A  ILE*     5.7     2.9    -      -       +      -
    814A  VAL*     3.8    17.9    -      -       +      +
    817A  CYS*     3.9    19.3    -      -       +      +
    818A  ALA*     3.6    29.2    -      -       +      +
    821A  LEU*     3.6    17.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 767 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    715A  SER*     2.8    32.2    +      -       -      +
    718A  GLY*     4.2     4.4    -      -       -      -
    763A  GLU*     2.9    23.5    +      -       -      +
    764A  SER*     3.7     9.8    +      -       -      +
    765A  CYS      3.3     0.2    -      -       -      -
    766A  LEU*     1.3    76.2    -      -       -      +
    768A  ALA*     1.3    57.3    +      -       -      +
    770A  THR*     3.5     8.7    +      -       -      +
    771A  GLY*     3.0    25.1    +      -       -      -
    817A  CYS*     3.9    22.8    -      -       -      -
     52B  LYS*     4.3    18.3    +      -       -      +
     55B  ARG*     3.5    33.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 768 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    714A  LEU*     3.6    21.3    +      -       -      +
    717A  PHE*     5.1     3.8    -      -       +      -
    718A  GLY*     3.9    10.0    -      -       -      +
    739A  LEU*     3.4    28.3    -      -       +      -
    764A  SER      3.0    12.0    +      -       -      +
    765A  CYS      3.0    10.1    +      -       -      +
    767A  GLU*     1.3    74.1    -      -       -      +
    769A  TYR*     1.3    66.0    +      -       -      +
    771A  GLY*     3.2     3.5    +      -       -      -
    772A  ILE*     3.1    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 769 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    736A  LEU*     3.8    21.9    +      -       +      -
    739A  LEU*     3.4    39.2    -      -       +      +
    740A  GLN*     3.7     4.5    +      -       -      -
    743A  SER*     3.8    13.4    +      -       -      -
    765A  CYS*     3.0    27.3    +      -       +      -
    766A  LEU*     3.9     5.8    -      -       -      +
    768A  ALA*     1.3    76.0    -      -       -      +
    770A  THR*     1.3    57.3    +      -       -      +
    772A  ILE*     3.1     6.8    +      -       +      +
    773A  VAL*     2.8    37.8    +      -       +      +
    790A  VAL*     5.7     1.8    -      -       +      -
    793A  ARG*     5.7     2.0    -      -       +      -
    796A  PHE*     3.5    26.9    -      +       -      -
    797A  ILE*     3.9    43.7    -      -       +      -
    800A  PHE*     4.5     9.2    -      +       -      -
    821A  LEU*     4.2    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 770 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    766A  LEU      3.0    19.0    +      -       -      -
    767A  GLU*     3.7     8.3    -      -       -      +
    769A  TYR*     1.3    76.7    -      -       -      +
    771A  GLY*     1.3    59.8    +      -       -      +
    773A  VAL*     3.9     1.7    -      -       -      -
    774A  GLN*     3.0    33.0    +      -       +      +
    817A  CYS      4.8     1.9    +      -       -      -
    820A  GLY      4.5     0.7    -      -       -      -
    821A  LEU*     3.8    19.0    +      -       -      +
    824A  ASP*     2.9    28.6    +      -       -      +
     59B  VAL*     3.9    31.9    -      -       +      -
     63B  ARG*     4.3     6.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 771 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    718A  GLY*     3.5    21.1    -      -       -      -
    721A  ALA*     3.4     9.0    -      -       -      +
    722A  LEU*     3.7    21.5    -      -       -      +
    767A  GLU      3.0    15.3    +      -       -      -
    768A  ALA      3.2     3.3    +      -       -      -
    770A  THR*     1.3    77.8    -      -       -      +
    772A  ILE*     1.3    55.9    +      -       -      +
    775A  GLY*     2.9    25.3    +      -       -      -
     59B  VAL*     5.7     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 772 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    717A  PHE*     5.3     2.5    -      -       +      +
    718A  GLY*     5.4     0.2    -      -       -      -
    721A  ALA*     4.0     9.0    -      -       +      -
    728A  PHE*     3.8    21.8    -      -       +      -
    732A  LEU*     4.0    21.5    -      -       +      -
    735A  VAL*     3.9    19.3    -      -       +      -
    736A  LEU*     4.3    12.1    -      -       +      -
    739A  LEU*     3.8    25.1    -      -       +      -
    768A  ALA*     3.1    17.6    +      -       +      +
    769A  TYR*     3.1     8.9    +      -       +      +
    771A  GLY*     1.3    76.1    -      -       -      +
    773A  VAL*     1.3    68.3    +      -       +      +
    776A  LEU*     2.9    38.6    +      -       +      +
    790A  VAL*     4.1    12.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 773 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    769A  TYR*     2.8    29.9    +      -       +      +
    770A  THR      4.1     2.2    -      -       -      +
    772A  ILE*     1.3    73.2    -      -       +      +
    774A  GLN*     1.3    64.1    +      -       -      +
    776A  LEU*     5.6     0.4    -      -       -      -
    777A  LYS*     3.3    19.7    +      -       +      +
    787A  VAL*     3.4    14.8    -      -       +      +
    790A  VAL*     4.8    19.3    -      -       +      -
    797A  ILE*     5.5     2.0    -      -       +      -
    821A  LEU*     4.8     4.3    -      -       +      -
    824A  ASP*     4.1    22.2    -      -       +      +
    825A  LEU*     4.2    20.0    -      -       +      -
    828A  ALA*     3.6    29.8    -      -       +      -
    829A  PHE*     4.8     4.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 774 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    722A  LEU*     3.9    18.3    -      -       +      +
    770A  THR*     3.0    24.7    +      -       +      +
    773A  VAL*     1.3    78.9    -      -       -      +
    775A  GLY*     1.3    57.8    +      -       -      +
    776A  LEU      3.4     0.2    -      -       -      -
    777A  LYS*     2.4    51.2    +      -       -      +
    778A  GLY      5.3     1.7    +      -       -      +
    824A  ASP*     2.9    40.5    +      -       -      +
    827A  THR*     5.2     3.2    -      -       -      +
    864A  TRP*     5.3     0.4    -      -       -      -
     59B  VAL*     4.9     8.3    -      -       +      -
     62B  ALA*     2.6    38.6    +      -       +      +
     63B  ARG*     4.3     9.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 775 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    721A  ALA*     3.6    17.7    -      -       -      -
    722A  LEU*     4.1     7.6    -      -       -      +
    725A  GLY*     3.1    25.5    -      -       -      -
    726A  GLY      4.2     0.7    +      -       -      -
    771A  GLY      2.9    21.8    +      -       -      -
    772A  ILE*     3.2     1.9    +      -       -      -
    774A  GLN*     1.3    80.8    -      -       -      +
    776A  LEU*     1.3    60.7    +      -       -      +
    777A  LYS      3.7     3.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 776 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    721A  ALA*     6.4     0.7    -      -       +      -
    725A  GLY      4.0    22.2    -      -       -      +
    726A  GLY*     4.5     6.4    +      -       -      +
    728A  PHE*     4.6    12.3    -      -       +      -
    729A  LYS*     4.6    11.2    -      -       +      +
    732A  LEU*     3.9    26.9    -      -       +      -
    772A  ILE*     2.9    24.3    +      -       +      +
    773A  VAL*     5.6     0.2    -      -       -      -
    775A  GLY*     1.3    77.5    -      -       -      +
    777A  LYS*     1.3    58.3    +      -       -      +
    781A  GLU*     4.4     1.2    -      -       -      +
    784A  HIS      3.5    15.8    -      -       -      +
    786A  ASP*     3.9    31.8    -      -       +      +
    787A  VAL*     3.5    23.1    -      -       +      +
    790A  VAL*     3.9    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 777 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    773A  VAL      3.3    11.9    +      -       -      +
    774A  GLN*     2.4    49.0    +      -       -      +
    775A  GLY      3.7     4.7    -      -       -      +
    776A  LEU*     1.3    79.5    -      -       -      +
    778A  GLY*     1.3    92.1    +      -       -      +
    781A  GLU*     4.0     4.9    -      -       -      +
    784A  HIS*     4.3    22.2    -      -       -      +
    787A  VAL*     3.4    24.0    -      -       +      -
    827A  THR*     3.2    43.6    -      -       -      +
    828A  ALA*     4.7    12.3    -      -       +      -
     62B  ALA      4.8     4.2    +      -       -      -
     63B  ARG      4.8     4.6    +      -       -      -
----------------------------------------------------------
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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